68 results on '"Univerza v Ljubljani"'
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2. Design of hybrid SDI-IP video systems for multi-purpose use
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Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Univerza v Ljubljani, Casas Pla, Josep Ramon, Pogačnik, Matevž, Tarrats Somalo, Sara, Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Univerza v Ljubljani, Casas Pla, Josep Ramon, Pogačnik, Matevž, and Tarrats Somalo, Sara
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Investigate the guidelines for developing modern hybrid SDI-IP based video solutions to support various video production activities such as live studio recording, promotional events, live broadcasting, lecture capture, production of high quality educational content, etc. The main focus should be on the standards for SDI and IP video solutions and the most known problems such as delays, routing, converters and mixers for multiple standards. The thesis should present hybrid system design proposals, schematics and suggestions for solving the main problems that can occur, Investigar las directrices para desarrollar soluciones de vídeo híbridas modernas basadas en SDI-IP para dar soporte a diversas actividades de producción de vídeo, como grabación en directo en estudio, eventos promocionales, retransmisión en directo, captura de conferencias, producción de contenidos educativos de alta calidad, etc. El enfoque principal debe estar en los estándares para soluciones de vídeo SDI e IP y los problemas más conocidos como retardos, enrutamiento, convertidores y mezcladores para múltiples estándares. La tesis debe presentar propuestas de diseño de sistemas híbridos, esquemas y sugerencias para resolver los principales problemas que se pueden presentar, Investigar les directrius per a desenvolupar solucions de vídeo híbrides modernes basades en *SDI-IP per a donar suport a diverses activitats de producció de vídeo, com a gravació en directe en estudi, esdeveniments promocionals, retransmissió en directe, captura de conferències, producció de continguts educatius d'alta qualitat, etc. L'enfocament principal ha d'estar en els estàndards per a solucions de vídeo *SDI i IP i els problemes més coneguts com a retards, encaminament, convertidors i mescladors per a múltiples estàndards. La tesi ha de presentar propostes de disseny de sistemes híbrids, esquemes i suggeriments per a resoldre els principals problemes que es poden presentar
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- 2024
3. Upgrade of the polymer filament extrusion device
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Universitat Politècnica de Catalunya. Departament d'Enginyeria Química, Univerza v Ljubljani, Pérez González, Juan Jesús, Valentinčič, Joško, Sabotin, Izidor, Castro Soldevila, Oriol, Universitat Politècnica de Catalunya. Departament d'Enginyeria Química, Univerza v Ljubljani, Pérez González, Juan Jesús, Valentinčič, Joško, Sabotin, Izidor, and Castro Soldevila, Oriol
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- 2023
4. Identifying and tracking physical objects with hyperledger decentralized applications
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Universitat Politècnica de Catalunya. Departament d'Enginyeria Telemàtica, Univerza v Ljubljani, Muñoz Tapia, José Luis, Pustišek, Matevž, Chicano Valenzuela, David, Universitat Politècnica de Catalunya. Departament d'Enginyeria Telemàtica, Univerza v Ljubljani, Muñoz Tapia, José Luis, Pustišek, Matevž, and Chicano Valenzuela, David
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El paso del tiempo ha dejado clara la tendencia a la descentralización. Las Distributed Ledger Technologies, como el Blockchain han aportado un abanico completo de nuevas posibilidades para mejorar, en este caso, la gestión de la confianza y la identidad en Internet, como lo hace la Self Sovereign Identity (SSI) . Esta tesis ha analizado el impacto del Blockchain para IoT con el proyecto Linux Foundation llamado Hyperledger, concretamente, con su solución Identity Stack. Aunque es un proyecto realmente sin madurar, tiene algunas herramientas útiles para empezar a entender y probar las capacidades de esta tecnología. Para aclarar las cosas, el proyecto consiste en una simulación de escenario práctico de comunicación y de envío credenciales verificadas entre una Raspberry Pi con un sensor RFID, que realizará el seguimiento del estado de entrega de un objeto, y una aplicación gráfica Java. Todo a través del Hyperledger SSI Stack, formado por una instancia pública de Indy Ledger y agentes Aries., El pas del temps ha deixat clara la tendència a la descentralització. Les Distributed Ledger Technologies, com el Blockchain han aportat un ventall complet de noves possibilitats per millorar, en aquest cas, la gestió de la confiança i la identitat a Internet, com ho fa la Self Sovereign Identity (SSI). Aquesta tesi ha analitzat l'impacte del Blockchain per a IoT amb el projecte Linux Foundation anomenat Hyperledger, concretament, amb la seva solució Identity Stack. Tot i que és un projecte realment sense madurar, té algunes eines útils per començar a entendre i provar les capacitats d'aquesta tecnologia. Per aclarir les coses, el projecte consisteix en una simulació d'escenari pràctic de communicació i d'enviament credencials verificades entre una Raspberry Pi amb un sensor RFID, que farà el seguiment de l'estat de lliurament d'un objecte, i una aplicació gràfica Java. Tot a través de l'Hyperledger SSI Stack, format per una instància pública d'Indy Ledger i agents Aries., The passing of time has made clear the trend of decentralization. Distributed ledger technologies like Blockchain have brought a full range of new possibilities to improve, in this case, trust and identity management on the internet as Self Sovereign Identity (SSI) does. This thesis has analyzed the Blockchain impact for IoT with the Linux Foundation Project called Hyperledger, concretely, with its Identity Stack solution. Even though it is a really unmatured project, it has some useful tools to start understanding and testing the capabilities of this technology. To make things clear, the project consists in a practical scenario simulation of communication and verified credentials sending between a Raspberry Pi with an RFID sensor, which will be tracking an object's state of delivery, and a graphical Java Application. Everything through the Hyperledger SSI Stack, formed by a public Indy network instance and Aries agents.
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- 2022
5. Estimation of a local inertia of power systems based on steady-state conditions
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Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, Rudež, Urban, Mampel Romeu, Marta, Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, Rudež, Urban, and Mampel Romeu, Marta
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The calculation of the inertia constant in systems with a large number of synchronous machines is a complex process. That is why, in the event of a disturbance, it is interesting to take into account only those machines that are affected. For this purpose, it is necessary to analyse the dynamic response of the system to a permanent disturbance at a network node. From this, it would be possible to define a radius of affectation that would allow to know which are the machines that must be taken into account when calculating the inertia constant of the system as a whole. This master thesis demonstrates how it is possible to predict the dynamic response of the sys- tem in order to avoid performing dynamic simulations. This is achieved using Synchronizing Power Coefficients, and all analyses are performed using MATLAB and Simulink, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.b - Per a 2030, ampliar la infraestructura i millorar la tecnologia per tal d’oferir serveis d’energia moderns i sostenibles per a tots els països en desenvolupament, en particular els països menys avançats, els petits estats insulars en desenvolupament i els països en desenvolupament sense litoral, d’acord amb els programes de suport respectius
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- 2022
6. Energy efficiency of solar collector with translucent photovoltaic cells
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Universitat Politècnica de Catalunya. Departament d'Enginyeria Química, Univerza v Ljubljani, Pérez González, Juan Jesús, Andreu Montolio, Ignacio, Universitat Politècnica de Catalunya. Departament d'Enginyeria Química, Univerza v Ljubljani, Pérez González, Juan Jesús, and Andreu Montolio, Ignacio
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Solar energy is a renewable source with the greatest potential for sustainable energy production. Among modern energy societies, the use of heat and electricity predominates. Both energy carriers can be produced with relatively high efficiency with solar energy utilization. However, the conversion efficiency is higher if heat and electricity is produced simultaneously. In the master's thesis, the research and technological trends in the field of combined solar heat and electricity generators (PV/T) is presented and the design of a solar PV/T generator is built on the basis of a commercial vacuum two-pipe solar collector was proposed. An algorithm for the calculation of solar radiation on the circular surface of the receiver was developed and a combined model of heat transfer and electricity production was built for determining the efficiency of solar energy utilization for heat and electricity. The model enables the determination of energy flows for PV/T generators with opaque and translucent solar cells. The model was validated with in-situ measurements of the stagnation temperature of the absorber. A validated model was then used to optimize the PV/T design with respect to the size of the photovoltaic module and its transmittance. Energy production was analyzed for different climatic conditions. Is found out that the optimum size angle of PV cells is 90° since increasing the size angle to 180°only provides 30% more electricity. In both cases PV cell does not affect significantly to heat production as it is reduced by approximately 5%.
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- 2022
7. Design of a 3D printed rotor balancing device
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Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, Van Wunnik, Lucas Philippe, Slavič, Janko, Lameiras De Carvalho, Eric, Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, Van Wunnik, Lucas Philippe, Slavič, Janko, and Lameiras De Carvalho, Eric
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There are many possible faults that can be found by mechanical vibration analysis in rotating equipment, such as imbalance and misalignment. This thesis will focus on dynamic models that follow the behavior of an unbalanced rigid rotor and will design a 3D print to build a softly mounted test bench. Finally, analyzing the data obtained from the sensors with a program developed in Python, various tests are carried out that demonstrate the effectiveness and correct operation of the designed device, Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura
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- 2021
8. Modelling photovoltaic system for a home energy management control
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Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, Inštitut "Jožef Stefan", COMSENSUS, Van Wunnik, Lucas Philippe, Čepin, Marko, Gili Selga, Albert, Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, Inštitut "Jožef Stefan", COMSENSUS, Van Wunnik, Lucas Philippe, Čepin, Marko, and Gili Selga, Albert
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Electrical energy demand is expected to increase in the upcoming years making more unsustainable the traditional ways to get it. For this reason, the world is increasing the share of renewable energy. However, the energy transition comes with some challenges due to the uncertainties of the natural resource grid as wind and solar. This change of paradigm is a reality for big-scale systems like the electricity grid and small-scale systems like a Home Energy Management System (HEMS). In essence, the objective of the thesis is to design a forecasting photovoltaic (PV) model versatile and generic for being able to adapt to the specifications of every system under investigation. The model is designed by considering and using parametric and non-parametric methods. This type of modelling is popularly known as grey-box modelling. The core of the model is defined by physics equations, so it is the parametric part of the model. However, this part has some assumptions and idealizations with it. For compensating them, two data-driven corrections are done following non-parametrical techniques. Therefore, the model takes advantage of both procedures. In order to validate the model, two case studies that consist of two PV systems located in different countries are defined. From their historical power output data and the forecast made by the PV model, it is possible to calculate their mismatch and verify the design model. In the end, the calculations show that the model is robust when it comes to forecasting even if the systems are located at different points, but it loses accuracy on those days that the sky is fully covered., Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.2 - Per a 2030, augmentar substancialment el percentatge d’energia renovable en el conjunt de fonts d’energia, Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles::11.1 - Per a 2030, assegurar l’accés de totes les persones a habitatges i a serveis bàsics adequats, segurs i assequibles, i millorar els barris marginal
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- 2021
9. Sandwich panel design suitable for selective laser sintering additive manufacturing
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Univerza v Ljubljani, Van Wunnik, Lucas Philippe, Klemenc, Jernej, Vidal Bravo, Pau, Univerza v Ljubljani, Van Wunnik, Lucas Philippe, Klemenc, Jernej, and Vidal Bravo, Pau
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Treball realitzat en el marc d'un programa de mobilitat amb la University of Ljubljana. Faculty of Mechanical Engineering, The use of the additive manufacturing revolutionizes the way to develop prototypes and final parts, because it allows shapes and structures not possible in traditional manufacturing processes. These technologies have been introduced to the market to satisfy the demand of personalized parts with high geometry complexity and small series, high valued products. In this thesis the focused will be put on the Selective Laser Sintering (SLS) additive manufacturing technology. The objective of this M.Sc. thesis is to develop a core of a sandwich panel that is useful for application in different structures, which are exposed to bending loads. The candidate should first acquire knowledge on the Selective Laser Sintering (SLS) by studying the relevant literature. Then the state-ofthe-art theoretical and practical topics related to the design of sandwich panels should be reviewed. This should be followed by a design of the most suitable panels that can be used for supporting the bending loads of planar structures. For each case of the panel three kind of static tests should be made, i.e. a compression, a shear and a three-point bending test. The experimental results should be comparedto the numerical simulations. For the most promising design(s) the pulsating fatigue tests should finallybe carried out to assess the fatigue resistance of such structures., Outgoing
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- 2021
10. Research of driver's perception of novel traffic signals using an eye tracker
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Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, Van Wunnik, Lucas Philippe, Ambrož, Miha, Kunc, Robert, Pliego Prim, Ignacio, Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, Van Wunnik, Lucas Philippe, Ambrož, Miha, Kunc, Robert, and Pliego Prim, Ignacio
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Novo Mesto is a small town in the Slovenian countryside which is undergoing a new project of road safety. New traffic signals are to be placed in bus stops to give drivers awareness of children standing waiting for the bus. Our mission is to use an eye tracker (the Dikablis device by Ergoneers) to study the reaction of three test drivers against these new signals; if they do detect them or not and if they modify their driving behavior once noticed them. The methodology is to do a first test before the signal placements and another one after, and afterwards compare both situations. Results are satisfying, with high values of reliability, and make us think the new signals will be useful and will contribute to make the road a safer place for children., Outgoing
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- 2019
11. Experimental study of threshold of movement in high slope streams in order to analyze flood risk assesment in mountain rivers
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Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, Technische Universiteit Delft, Technische Universität Dresden, Univerza v Ljubljani, Bateman Pinzón, Allen, Medina Iglesias, Vicente César de, Bhattacharya, Biswa, Lin, Chien-Chih, Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, Technische Universiteit Delft, Technische Universität Dresden, Univerza v Ljubljani, Bateman Pinzón, Allen, Medina Iglesias, Vicente César de, Bhattacharya, Biswa, and Lin, Chien-Chih
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In order to improve our knowledge of the behaviour of Rivers Mountains and the risk associated to them, this TFM propose to study experimentally the morphodynamic behaviour of these rivers under avenue situation. The consequences of floods in High Mountain rivers are complex because the high slopes and the scour of the banks. Those processes studied superficially until today. The aim of the present work is to understand deeply those processes understanding the threshold of motion in high slopes rivers and the influence of it in the study of floods., Incoming
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- 2019
12. Design of a bending beam for manufacturing with additive technologies
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Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, Van Wunnik, Lucas Philippe, Klemenc, Jernej, Mendieta Pons, Pau, Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, Van Wunnik, Lucas Philippe, Klemenc, Jernej, and Mendieta Pons, Pau
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Prototyping or materialisation is an expensive stage of Product Design. In a lot of cases, the same technology is both used for the final product and test models; this makes the prototype units very expensive. The use of Additive Manufacturing to build prototypes and small lot parts might be incredibly useful in the future, reducing costs drastically. On the other hand, a large number of units should be build using ordinary methods, being more efficient when it comes to Mass Production. In this thesis, the limitations of Additive Manufacturing are faced creating a method that allows the production of semi-hollow parts. Depending on the AM Technology used and its own limitations, different geometries and parameters may change, allowing the part to be more or less hollow. However, the AM method designed would be the same. The current method has been tested using Fused Deposition Modelling Technology on PLA plastic. The bending beams were successfully printed and tested, giving good results and repeatability. Moreover, having determined that it works on FDM, the same method could be used for Powder Bed Fusion Technology and other AM Technologies.
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- 2019
13. Mechanical load analysis and benchmarking of one-way clutches for e-bike drives
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Univerza v Ljubljani, Tavčar, Jože, Viñals Domènech, Enric, Univerza v Ljubljani, Tavčar, Jože, and Viñals Domènech, Enric
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An overview of one-way clutches, used design principles and criteria for selection was prepared. The main problem while designing an e-bike drive using a sprag clutch was the assembly tolerances. Therefore, an analysis using the finite element method of two different type of clutches was conducted. In order to do these analyses, 3D model of sprag clutch and the ratchet and pawl clutch have been created. For each clutch type the calculations of the loads have been made, and used them to run the simulations. Once the simulations have been done, the deformation and the von Mises stress values have been checked to verify if the designs could bear the loads applied. After verifying the models, the materials, which the clutches should be made in order to bear the applied loads, are proposed. On the base of multiple criteria assessment ratchet and pawl clutch was selected as more appropriate, Outgoing
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- 2018
14. Application of heterogeneous fenton oxidation for the removal of pollutants from wastewater
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Univerza v Ljubljani, Van Wunnik, Lucas Philippe, Žgajnar Gotvajn, Andreja, Rodríguez Rey, Daniel, Univerza v Ljubljani, Van Wunnik, Lucas Philippe, Žgajnar Gotvajn, Andreja, and Rodríguez Rey, Daniel
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During the last century there has been a growing concern about water pollution throughout the developed countries. Water has a major impact on the environment as it is used by all living being. This leads to leave the wastewater used with an acceptable quality for its next destination. Fortunately, national and international water quality agreements and laws have pushed development of wastewater treatment technology that nowadays allows us to return the used water to the environment in good conditions. Nevertheless, more modern and simpler technologies should be researched in order to make wastewater treatment a process reachable all around the world within the minimum environmental impact and minimizing waste. This thesis researches one of the technologies with more future in this field; the Fenton process, a reaction that belongs to the Advanced Oxidation Processes (AOPs). The aim of this thesis is to optimise the Fenton reaction. This has been done by testing different catalysts, concentration of chemicals, and operational conditions. In this context, the experiments performed in the frame of this study have explored: - The feasibility of the iron/iron oxide catalyst. - The optimum reactive conditions for the heterogeneous Fenton process; the reaction pH, concentration of the H2O2 and temperature. - The optimal preparation of the catalyst in terms of its level of oxidation and Its potentials or limitations in applied Fenton process. Towards the checking of these parameters the experiments were conducted using propionic acid (PA) as a model of organic substance with nine different iron oxide catalysts in order to simulate a wastewater sample under the Fenton’s reaction and with a regular checking of the amount of total organic carbon (TOC) with time. Obtained results showed good process efficiency near to 50% of TOC removal, working at a smoothly acid pH and without remarkable iron leaching at 60 ºC and an excess of H2O2.
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- 2014
15. Emulsion copolymerization of n-Butyl acrylate with modified glucose
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Univerza v Ljubljani, Sebenik, Urska, Garcia Blanch, Elisa, Univerza v Ljubljani, Sebenik, Urska, and Garcia Blanch, Elisa
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In the present work an emulsion copolymerization of n-butyl acrylate monomer and secondary renewable monomer derived from glucose is presented. The latter component offers to this study a plus of sustainability, considering that it is a renewable material. The study also considers the price factor of renewable monomer and to determine best price/performance ratio. The content of the renewable monomer in the final product could be from 10% to 30% of the total monomer amount. The study is focused on reaching a stable product with appropriate adhesive properties. There are several factors that affect the properties of the final product. For this reason the variation of the quantity of the substances that participate in the reaction and variable chemical and process parameters are being studied. In any case, the final product is compound of two before mentioned monomers, two types of emulsifiers (one anionic that stabilizes the monomer droplets by electrostatic repulsion and other non-ionic that provides steric stabilization), an stabilizer of the reaction from the family of polyvinyl alcohol, sodium carbonate and a water soluble initiator (ammonium persulfate). The process that has been chosen for this study is semi-batch, being that it offers a better control of the reaction temperature since the copolymerization reactions between the aforementioned monomers is highly exothermic. The reactor is initially charged with the monomers, emulsifiers, initiator and water. The rest of n-BA monomer is added to the reactor during a period of time of 100 minutes. Nitrogen is also used in this process in order to remove the oxygen that could affect the initiation phase. During the reaction is in line monitored by IR spectroscopy, which allows visualising the reduction of the carbon-carbon double bonds and the appearance of single ones. Attention is also focused on the evaluation of the particles size distribution of the final product, which has to be close to 1 μm. Basic adhesive, Outgoing
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- 2013
16. Synthesis and characterization of Ni-Mn-Ga alloys with addition of Cu
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Univerza v Ljubljani, Naglič, Iztok, Conesa Martin, Albert, Univerza v Ljubljani, Naglič, Iztok, and Conesa Martin, Albert
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Non-stoichiometric Heusler Ni-Mn-Ga based alloys with addition of up to 7,5 at.% of Cu were prepared. Homogenized alloys were characterized using polarized light microscopy, X-ray diffraction, differential scanning calorimetry and differential thermal analysis, vibrating sample magnetometer analysis and nanoindentation. Results of polarised light microscopy have revealed that all the alloys prepared, either in as-cast or homogenized state, have martensitic microstructure. X-ray diffraction has proved that tetragonal non-modulated martensite is present in all homogenised alloys. In a sample with the highest addition of copper MnO was also found. Thermal analysis revealed that the Curie temperatures decrease with e/a concentration and temperatures of martensitic transformation increases with e/a concentration. It was also found that saturation magnetization has decreased with increasing copper content for the samples with Curie temperature above room temperature (samples with copper concentration up to 2,77 at.%). Nanoindentation experiments suggest that hardness and elasticity modulus are increasing with increasing copper content., Outgoing
- Published
- 2013
17. Thermal fatigue of high chromium steel rolls
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Univerza v Ljubljani, Fajfar, Peter, Valverde Montraveta, Gerard, Univerza v Ljubljani, Fajfar, Peter, and Valverde Montraveta, Gerard
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Within the master work the phenomenon of appearance of firecracks on the surface of the work rolls that occur during hot rolling of flat products in the case of regular rolling conditions and in the case of the rolling mill stalls was investigated. During hot rolling work rolls are subjected to successive heating and cooling conditions. Their surface is exposed to rapid temperature changes due to the contact with hot rolled material and due to cold water used for rolls cooling. These cyclic heating/cooling conditions cause thermal fatigue which is one of the most important factors affecting the rate of surface deterioration as well as mechanical fatigue and abrasion. Two different tests for the laboratory assessments of the thermal fatigue resistance of the high-chromium steel rolls were used. The first test enables a simulation of the work roll thermal fatigue in the case of regular rolling conditions. Furthermore, with the second test thermal fatigue of work rolls in the case of the rolling mill stalls was investigated. Both tests were implemented in a thermo-mechanical simulator of metallurgical states, the Gleeble 1500D. Finite elements method simulations were performed to determinate the temperature distribution in the work rolls by using NSC.SuperForm software. Evident dependence of the crack nucleation and their growth with the temperature and the cooling medium was found but no dependence due to the length of contact time was found. The influence of slab thickness and slab initial temperature to the temperature evolution in the surface layer of the work roll was estimated. The master work contributes to better understanding of crack nucleation and their growth during the usual hot rolling conditions, as well as for the case of rolling mill stalls., Outgoing
- Published
- 2013
18. Emotion recognition from speech signals
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Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Univerza v Ljubljani, Kosir, Andrej, Escalona Mena, Marc, Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Univerza v Ljubljani, Kosir, Andrej, and Escalona Mena, Marc
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Treball realitzat en el marc d'un programa de mobilitat amb la University of Ljubljana. Faculty of Electrical Engineering, [ANGLÈS] The two main objectives of this project are to analyse the efficiency of several techniques widely used among the field of emotion recognition through spoken audio signals, and, secondly, obtain empirical data that proves that it is actually plausible to do so with a more than acceptable performance rate., [CASTELLÀ] Los dos objetivos principales de este PFC son, en primer lugar, describir meticulosamente diversas técnicas utilizadas hoy en día por los desarrolladores del sector multi-disciplinario del reconocimiento de emociones a través del habla. En segundo lugar, y escogiendo nuestra manera de encarar el campo, obtener un amplio volumen de datos que confirmen que es actualmente viable conseguir resultados más que satisfactorios., [CATALÀ] Els dos objectius principals d'aquest PFC són, en primer lloc, descriure meticulosament diverses tècniques emprades avui en dia dins el sector de reconeixement d'emocions a través de senyals d'audio, i , en segon lloc, proveïr un important volum de dades que demostrin que és totalment plausible aconseguir un més que acceptable funcionament
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- 2012
19. The impact of self-similarity on queues utilitzation
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Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Univerza v Ljubljani, Zemva, Andrej, Perez Jorge, Nicolas, Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Univerza v Ljubljani, Zemva, Andrej, and Perez Jorge, Nicolas
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Projecte final de de carrera fet en col.laboració amb University of Ljubljana. Faculty of Electrical Engineering, English: Analysis of the impact of traffic self-similarity on queues utilization of a telecommunication network's device through the software tool Opnet modeler., Castellano: Análisis del impacto del tráfico autosimilar en la utilización de una cola de un dispositivo de una red de telecomunicaciones mediante el simulador Opnet modeler., Català: Anàlisi de l'mpacte del tràfic autosimilar en la utilizació d'una cua d'un dispositiu que pertany a una xarxa de telecomunicacions mitjançant el software Opnet modeler.
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- 2011
20. A verification of selected properties of Telecommunication traffic generated by OPNET simulator
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Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Univerza v Ljubljani, Kosir, Andrej, Alonso Martinez, Daniel, Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Univerza v Ljubljani, Kosir, Andrej, and Alonso Martinez, Daniel
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Projecte final de carrera fet en col.laboració amb University of Ljubljana. Faculty of Electrical Engineering., English: Nowadays, telecommunication has become an essential service in our daily lives. The exchange of information generates high data traffic in the networks. Analyzing and modelling network traffic is becoming one of the biggest challenges for communication companies when planning networks and developing communication equipments are their aims. Recent examinations of local area network traffic and wide area network traffic have challenged the commonly assumed models for network traffic, e.g., the Poisson distribution. Once traffic follows a Poisson or Markovian arrival process, it would have a characteristic burst length which would tend to be smoothed by averaging over a long enough time scale. Whereas, measurements of real traffic indicate that significant traffic variance (burstiness) is present on a wide range of time scales. Traffic that is bursty on many or all time scales can be described statistically using the notion of self-similarity. The aim of the assignment is to test the selected properties of randomly generated telecommunication traffic using OPNET network simulator. These properties are stationary and self-similarity related to type of traffic sources and the number of sources. The theoretical tools include known statistical tests for stationary and procedures for Hurst parameter estimation including the test for self-similarity. The traffic analysis will be performed using SELFIS tool., Castellano: Analizar y modelar el tráfico de la red es uno de los mayores desafíos actuales para las compañías de telecomunicaciones. Nuevos estudios han demostrado que los modelos como Poisson no permiten describir las características del tráfico real. Actualmente, el trafico LAN y WAN presenta variabilidad en diferentes rangos de tiempo, el trafico que presenta estas características puede ser descrito estadísticamente utilizando la auto-semejanza. El objetivo de este PFC es testear las propiedades del tráfico aleatorio generado por el simulador de redes OPNET. Estas propiedades son: estacionalidad y auto-semejanza dependiendo del tipo de fuentes de tráfico que tengamos y el número de ellas. Las herramientas teóricas utilizadas son scripts para estudiar la estacionalidad y procedimientos para obtener el parámetro de Hurst. El análisis del tráfico se ha realizado utilizando la herramienta SELFIS., Català: Analitzar i modelar el tràfic de les xarxes es un dels grans reptes actuals per les companyies de telecomunicació. Nous estudis han demostrat que els models com Poisson no permeten descriure les característiques del tràfic real. Actualment, el tràfic LAN i WAN presenta variabilitat en diferents rangs de temps, el tràfic que presenta aquestes característiques pot ser descrit estadísticament utilitzant ?Self-similarity. L'objectiu del PFC es testejar les propietats del tràfic aleatori generat pel simulador de xarxes OPNET. Aquestes propietats son: estacionalitat i "self-similarity" tenint en compte el tipus de fonts de tràfic que existeixen i el nombre d?elles utilitzades. Las eines teòriques utilitzades son "scripts" per estudiar la estacionalitat i procediments per obtenir el paràmetre de Hurst. L'anàlisi del tràfic s'ha realitzat utilitzant el programa SELFIS.
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- 2011
21. Powiedz mi, co jesz, a powiem ci, kim jesteś – o kulinariach w Słowenii
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Maria Wacławek, Maria Wtorkowska, Univerza v Ljubljani, Filozofska fakulteta, Oddelek za slavistiko, Aškerčeva c. 2, 1000 Ljubljana, Slovenija, ORCID: 0000-0002-3307-5338., Univerza v Ljubljani, Filozofska fakulteta, Oddelek za slavistiko, Aškerčeva c. 2, 1000 Ljubljana, Slovenija, ORCID: 0000-0001-9317-2490., and mariazofia.wtorkowska@ff.uni-lj.si
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Vocabulary ,History ,Cultural identity ,media_common.quotation_subject ,Slovenia ,kulinaria ,General Engineering ,linguistic worldview ,językowy obraz świata ,Identity (social science) ,Stereotype ,The arts ,Słowenia ,Visual arts ,lcsh:Philology. Linguistics ,stereotyp ,lcsh:P1-1091 ,culinary arts ,stereotype ,media_common - Abstract
Culinary arts are an important part of every nation’s culture. The goal of our text is to converge the linguistic-cultural view of Slovene culinary arts from a hetero-stereotypical point of view of Polish people. For our analysis, we used operational categories of an ethnolinguistic school from Lublin and its continuators from all over Poland. The article is based on academic surveys. We differentiated and wrote about two thematic circles, which reconstruct Slovene culinary arts: 1) the general characteristics of Slovene cuisine, 2) specific dishes, ingredients, drinks etc. The linguistic worldview captured in the discourse on culinary identity are one of the main factors influencing the cultural identity of a given community. The vocabulary, especially culturally conditioned, regarding the culinary arts should find its place in the glottodidactic process. Kulinaria są ważnym składnikiem każdej kultury narodowej. Tekst ma na celu przybliżenie językowo-kulturowego obrazu słoweńskich kulinariów w perspektywie heterostereotypowej, widzianego oczyma Polaków. W analizie wykorzystano kategorie operacyjne wypracowane przez lubelską szkołę etnolingwistyczną i jej kontynuatorów z całej Polski. Bazę materiałową artykułu stanowią dane ankietowe. Wyróżniono i opisano dwa kręgi tematyczne, które współtworzą rekonstruowany obraz słoweńskich kulinariów: 1) ogólna charakterystyka kuchni w Słowenii, 2) konkretne dania, składniki, napoje itp. Tak ujęte badania językowego obrazu świata włączają się w dyskurs o tożsamości kulinarnej, będącej jednym z istotnych czynników wpływających na odrębność kulturową danej wspólnoty. Słownictwo z zakresu kulinariów, zwłaszcza uwarunkowane kulturowo, powinno więc znaleźć swoje miejsce w procesie glottodydaktycznym.
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- 2019
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22. Identifying and tracking physical objects with hyperledger decentralized applications
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Chicano Valenzuela, David, Universitat Politècnica de Catalunya. Departament d'Enginyeria Telemàtica, Univerza v Ljubljani, Muñoz Tapia, José Luis, and Pustišek, Matevž
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technological innovations ,Enginyeria de la telecomunicació::Telemàtica i xarxes d'ordinadors [Àrees temàtiques de la UPC] ,innovaciones tecnológicas ,Innovacions tecnològiques - Abstract
El paso del tiempo ha dejado clara la tendencia a la descentralización. Las Distributed Ledger Technologies, como el Blockchain han aportado un abanico completo de nuevas posibilidades para mejorar, en este caso, la gestión de la confianza y la identidad en Internet, como lo hace la Self Sovereign Identity (SSI) . Esta tesis ha analizado el impacto del Blockchain para IoT con el proyecto Linux Foundation llamado Hyperledger, concretamente, con su solución Identity Stack. Aunque es un proyecto realmente sin madurar, tiene algunas herramientas útiles para empezar a entender y probar las capacidades de esta tecnología. Para aclarar las cosas, el proyecto consiste en una simulación de escenario práctico de comunicación y de envío credenciales verificadas entre una Raspberry Pi con un sensor RFID, que realizará el seguimiento del estado de entrega de un objeto, y una aplicación gráfica Java. Todo a través del Hyperledger SSI Stack, formado por una instancia pública de Indy Ledger y agentes Aries. El pas del temps ha deixat clara la tendència a la descentralització. Les Distributed Ledger Technologies, com el Blockchain han aportat un ventall complet de noves possibilitats per millorar, en aquest cas, la gestió de la confiança i la identitat a Internet, com ho fa la Self Sovereign Identity (SSI). Aquesta tesi ha analitzat l'impacte del Blockchain per a IoT amb el projecte Linux Foundation anomenat Hyperledger, concretament, amb la seva solució Identity Stack. Tot i que és un projecte realment sense madurar, té algunes eines útils per començar a entendre i provar les capacitats d'aquesta tecnologia. Per aclarir les coses, el projecte consisteix en una simulació d'escenari pràctic de communicació i d'enviament credencials verificades entre una Raspberry Pi amb un sensor RFID, que farà el seguiment de l'estat de lliurament d'un objecte, i una aplicació gràfica Java. Tot a través de l'Hyperledger SSI Stack, format per una instància pública d'Indy Ledger i agents Aries. The passing of time has made clear the trend of decentralization. Distributed ledger technologies like Blockchain have brought a full range of new possibilities to improve, in this case, trust and identity management on the internet as Self Sovereign Identity (SSI) does. This thesis has analyzed the Blockchain impact for IoT with the Linux Foundation Project called Hyperledger, concretely, with its Identity Stack solution. Even though it is a really unmatured project, it has some useful tools to start understanding and testing the capabilities of this technology. To make things clear, the project consists in a practical scenario simulation of communication and verified credentials sending between a Raspberry Pi with an RFID sensor, which will be tracking an object's state of delivery, and a graphical Java Application. Everything through the Hyperledger SSI Stack, formed by a public Indy network instance and Aries agents.
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- 2022
23. Estimation of a local inertia of power systems based on steady-state conditions
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Mampel Romeu, Marta, Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, and Rudež, Urban
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Electric power transmission -- Computer simulation ,Electric power systems -- Automatic control -- Mathematical models ,Energia elèctrica--Transmissió -- Simulació per ordinador ,Enginyeria elèctrica::Distribució d’energia elèctrica [Àrees temàtiques de la UPC] ,Sistemes de distribució d'energia elèctrica -- Control automàtic -- Models matemàtics - Abstract
The calculation of the inertia constant in systems with a large number of synchronous machines is a complex process. That is why, in the event of a disturbance, it is interesting to take into account only those machines that are affected. For this purpose, it is necessary to analyse the dynamic response of the system to a permanent disturbance at a network node. From this, it would be possible to define a radius of affectation that would allow to know which are the machines that must be taken into account when calculating the inertia constant of the system as a whole. This master thesis demonstrates how it is possible to predict the dynamic response of the sys- tem in order to avoid performing dynamic simulations. This is achieved using Synchronizing Power Coefficients, and all analyses are performed using MATLAB and Simulink Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.b - Per a 2030, ampliar la infraestructura i millorar la tecnologia per tal d’oferir serveis d’energia moderns i sostenibles per a tots els països en desenvolupament, en particular els països menys avançats, els petits estats insulars en desenvolupament i els països en desenvolupament sense litoral, d’acord amb els programes de suport respectius
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- 2022
24. Energy efficiency of solar collector with translucent photovoltaic cells
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Andreu Montolio, Ignacio, Pérez González, Juan Jesús, Universitat Politècnica de Catalunya. Departament d'Enginyeria Química, and Univerza v Ljubljani
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Measurement ,Energies [Àrees temàtiques de la UPC] ,Design optimization ,Photovoltaic thermal technology ,Photovoltaic power generation ,Solar collectors ,Energia solar fotovoltaica ,Numerical model - Abstract
Solar energy is a renewable source with the greatest potential for sustainable energy production. Among modern energy societies, the use of heat and electricity predominates. Both energy carriers can be produced with relatively high efficiency with solar energy utilization. However, the conversion efficiency is higher if heat and electricity is produced simultaneously. In the master's thesis, the research and technological trends in the field of combined solar heat and electricity generators (PV/T) is presented and the design of a solar PV/T generator is built on the basis of a commercial vacuum two-pipe solar collector was proposed. An algorithm for the calculation of solar radiation on the circular surface of the receiver was developed and a combined model of heat transfer and electricity production was built for determining the efficiency of solar energy utilization for heat and electricity. The model enables the determination of energy flows for PV/T generators with opaque and translucent solar cells. The model was validated with in-situ measurements of the stagnation temperature of the absorber. A validated model was then used to optimize the PV/T design with respect to the size of the photovoltaic module and its transmittance. Energy production was analyzed for different climatic conditions. Is found out that the optimum size angle of PV cells is 90° since increasing the size angle to 180°only provides 30% more electricity. In both cases PV cell does not affect significantly to heat production as it is reduced by approximately 5%.
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- 2022
25. Memory landscapes in (post)Yugoslavia - The case of Republic of Bosnia and Herzegovina
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Milica Popovic, Natalija Majsova, Monika Palmberger, Centre de recherches internationales (CERI), Sciences Po (Sciences Po)-Centre National de la Recherche Scientifique (CNRS), Univerza v Ljubljani, University of Vienna [Vienna], and Centre de recherches internationales (Sciences Po, CNRS) (CERI)
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generations ,ethnic divisions ,divided cities ,[SHS.HIST]Humanities and Social Sciences/History ,memory politics ,[SHS.SCIPO]Humanities and Social Sciences/Political science ,Yugonostalgia - Abstract
As Bosnia and Herzegovina remains a country institutionally-divided on an ethno-national basis between its three consitutuent peoples – Bosniaks, Croats and Serbs, top-down memory politics encourage these divisions. Using the still divided city of Mostar as an example, Dr. Monika Palmberger gives insight into the discursive tactics opposing hegemonic memory narratives, through a generational approach and focusing on the generation of the Last Yugoslavs, thus underlining the importance of studying the integrative potential of positive memories of the pre-war period.
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- 2021
26. Memory landscapes in (post)Yugoslavia - The case of Republic of Serbia
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Milica Popovic, Natalija Majsova, Jelena Đureinović, Centre de recherches internationales (CERI), Sciences Po (Sciences Po)-Centre National de la Recherche Scientifique (CNRS), Univerza v Ljubljani, and Centre de recherches internationales (Sciences Po, CNRS) (CERI)
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Chetnik movement ,revisionism ,[SHS.HIST]Humanities and Social Sciences/History ,memory politics ,anticommunism ,[SHS.SCIPO]Humanities and Social Sciences/Political science - Abstract
Since the 2000s, the Republic of Serbia has been marked by a surge in revisionist memory politics. Encouraged by EU memory narratives, which equate fascism and communism, revisionist memory politics in Serbia entails a rehabilitation of the Chetnik movement. In this interview, historian Dr Jelena Đureinović debunks the myths surrounding the memory battles in the public space in Serbia and analyzes the diverging memory narratives in the country and in the wider (post)Yugoslav region. Đureinović explains how the ethnicization and revisionism of memory and history have been reflected in the newly adopted legal frameworks, judicial processes, mainstream political discourses and in the overall memory efforts of the political elites, including the Serbian Orthodox Church. While memory battles involving heterogeneous voices in Serbia remain focused on World War Two, seemingly more pertinent issues, namely, the reconciliation with the war past of the 1990s, are effectively obfuscated.
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- 2021
27. Memory landscapes in (post)Yugoslavia - The case of Croatia
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Milica Popovic, Natalija Majsova, Sanja Horvatinčić, Centre de recherches internationales (CERI), Sciences Po (Sciences Po)-Centre National de la Recherche Scientifique (CNRS), Univerza v Ljubljani, and Centre de recherches internationales (Sciences Po, CNRS) (CERI)
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[SHS.HIST]Humanities and Social Sciences/History ,(post)Yugoslav space ,memory politics ,[SHS.SCIPO]Humanities and Social Sciences/Political science ,monuments ,heritage studies - Abstract
As the Republic of Croatia is considered today to be the stronghold of anti-Yugoslav sentiments among (post)Yugoslav states, we look into the complexities and nuances of memory politics in this newest EU member state. Mainstream narratives are embedded in the national reconciliation policies and anti-communism emanating from Franjo Tudjman’s politics in the 1990s and the Homeland war. Through historical revisionism of World War Two and the role of Ustasha movement, they profoundly influence Croatian approaches to socialist heritage. Dr Sanja Horvatinčić further elucidates the key mnemonic actors in Croatia and how the destruction and the dereliction of the monuments from the socialist Yugoslavia have been an important element in Croatian nation-building, encouraged by “anti-totalitarian” European memory activism.
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- 2021
28. Design of a 3D printed rotor balancing device
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Lameiras De Carvalho, Eric, Van Wunnik, Lucas Philippe, Slavič, Janko, Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, and Univerza v Ljubljani
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Three-dimensional printing ,Enginyeria mecànica [Àrees temàtiques de la UPC] ,Rotors -- Vibració -- Models matemàtics ,Impressió 3D ,Rotors -- Vibration -- Mathematical models - Abstract
There are many possible faults that can be found by mechanical vibration analysis in rotating equipment, such as imbalance and misalignment. This thesis will focus on dynamic models that follow the behavior of an unbalanced rigid rotor and will design a 3D print to build a softly mounted test bench. Finally, analyzing the data obtained from the sensors with a program developed in Python, various tests are carried out that demonstrate the effectiveness and correct operation of the designed device Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura
- Published
- 2021
29. Sandwich panel design suitable for selective laser sintering additive manufacturing
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Vidal Bravo, Pau, Univerza v Ljubljani, Van Wunnik, Lucas Philippe, and Klemenc, Jernej
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Three-dimensional printing ,Additive manufacturing ,Sinterització ,Enginyeria electrònica [Àrees temàtiques de la UPC] ,Làsers -- Aplicacions industrials ,Laser sintering ,Lasers - Industrial applications ,Impressió 3D - Abstract
Treball realitzat en el marc d'un programa de mobilitat amb la University of Ljubljana. Faculty of Mechanical Engineering The use of the additive manufacturing revolutionizes the way to develop prototypes and final parts, because it allows shapes and structures not possible in traditional manufacturing processes. These technologies have been introduced to the market to satisfy the demand of personalized parts with high geometry complexity and small series, high valued products. In this thesis the focused will be put on the Selective Laser Sintering (SLS) additive manufacturing technology. The objective of this M.Sc. thesis is to develop a core of a sandwich panel that is useful for application in different structures, which are exposed to bending loads. The candidate should first acquire knowledge on the Selective Laser Sintering (SLS) by studying the relevant literature. Then the state-ofthe-art theoretical and practical topics related to the design of sandwich panels should be reviewed. This should be followed by a design of the most suitable panels that can be used for supporting the bending loads of planar structures. For each case of the panel three kind of static tests should be made, i.e. a compression, a shear and a three-point bending test. The experimental results should be comparedto the numerical simulations. For the most promising design(s) the pulsating fatigue tests should finallybe carried out to assess the fatigue resistance of such structures. Outgoing
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- 2021
30. Predatory mites (Acari: Phytoseiidae) first recorded on cultivated plants in Slovenia in the period 2012-2017
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Gijsbertus Vierbergen, Serge Kreiter, Tanja Bohinc, Marie-Stéphane Tixier, Stanislav Trdan, Univerza v Ljubljani, Centre de Biologie pour la Gestion des Populations (UMR CBGP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université de Montpellier (UM)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Ministry of Agriculture, Nature and Food Quality, Bohinc, T., and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)
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0106 biological sciences ,Euseius stipulatus ,Phytoseiidae ,010607 zoology ,Biological pest control ,slovénie ,Zoology ,prve najdbe ,Biology ,plenilske pršice ,01 natural sciences ,biotično varstvo rastlin ,Predation ,lcsh:Agriculture ,mite ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,Acari ,Slovenija ,Water Science and Technology ,Cultivated plant taxonomy ,Vegetal Biology ,Euseius gallicus ,Microbiology and Parasitology ,lcsh:S ,biology.organism_classification ,Microbiologie et Parasitologie ,prédateur ,010602 entomology ,[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology ,Period (geology) ,General Agricultural and Biological Sciences ,Biologie végétale - Abstract
In the period 2012-2017 we investigated the occurrence of indigenous species of predatory mites in different cultivated plants in Slovenia. In a comprehensive study we confirmed the occurrence of the following predatory mites: Amblyseius andersoni (Chant, 1957), Euseius finlandicus (Oudemans, 1915), Euseius gallicus (Kreiter & Tixier, 2009), Euseius stipulatus (Athias-Henriot, 1960), Kampimodromus abberans (Oudemans, 1930), Neoseiulus californicus (McGregor, 1954), Paraseiulus triporus (Chant & Shaul, 1982) and Phytoseius horridus (Ribaga, 1904). In the paper all seven species are presented, but for the field of biological control A. andersoni, E. gallicus and N. californicus are the most interesting species. The first two of them are already on the List of indigenous organisms for the purpose of biological control, while the third will be placed into it in the near future. All three of them have a great potential in biological control, since they can be found in different host plants.
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- 2018
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31. Reflective mimesis and ethics of the cross in the mimetic theory of Rene Girard: towards an inclusive humanism : doctoral dissertation
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Ekpunobi, Anthony, Petkošek, Robert, TEOF - Teološka fakulteta, and Univerza v Ljubljani
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Mímesis ,Psicología interpersonal - Abstract
According to René Girard’s anthropological interpretation of the Event of the cross of Jesus Christ, the cross represents the historical moment when the unjust nature of the scapegoat mechanism that held sway of primitive society was exposed. In his Mimetic Theory, mimetic desire is the unconscious, involuntary, uncontrollable driving force of human acts. He proffered the Imitation of Christ i.e. a reversal of the will to violence, as the solution to scapegoating. Unfortunately, the imitation of Christ involves a mental reflection that is inconsistent with the mimetic theory. This Christological solution i.e. the Imitation of Christ, to an anthropological crisis as proposed by Girard does not make for a rational understanding of the action of the cross. On the contrary, a reflective mimesis informed by the action of the cross, is supportive of a rational understanding of the cross as such, unaided by any appeal to religious faith. This thesis argues for reflective mimesis as an ethical disposition, a paradigm and a point of reference of social integration. Según la interpretación antropológica de René Girard del acontecimiento de la cruz de Jesucristo, la cruz representa el momento histórico en el que se puso de manifiesto la naturaleza injusta del mecanismo de chivo expiatorio que dominaba la sociedad primitiva. En su teoría mimética, el deseo mimético es la fuerza motriz inconsciente, involuntaria e incontrolable de los actos humanos. Propuso la imitación de Cristo, es decir, la inversión de la voluntad de violencia, como solución al chivo expiatorio. Desgraciadamente, la imitación de Cristo implica una reflexión mental que es incoherente con la teoría mimética. Esta solución cristológica, es decir, la imitación de Cristo, a una crisis antropológica, tal como la propone Girard, no permite una comprensión racional de la acción de la cruz. Por el contrario, una mimesis reflexiva informada por la acción de la cruz, apoya una comprensión racional de la cruz como tal, sin ayuda de ninguna apelación a la fe religiosa. Esta tesis defiende la mimesis reflexiva como una disposición ética, un paradigma y un punto de referencia de la integración social. post-print 279 p.
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- 2020
32. Optimization over trace polynomials
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Jurij Volčič, Victor Magron, Igor Klep, University of Ljubljana, Équipe Méthodes et Algorithmes en Commande (LAAS-MAC), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Institut de Mathématiques de Toulouse UMR5219 (IMT), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Department of Mathematics [Texas A&M University], Texas A&M University [College Station], FMJH Program PGMO (EPICS project) and EDF, Thales, Orange et Criteo, Slovenian Research Agency grants J1-8132 and P1-0222, NSF grant DMS-1954709, Proteus grant 46195TA QUANTPOP, ANR-18-ERC2-0004,COPS,Optimisation garantie pour la vérification des systèmes cyber-physiques(2018), ANR-19-P3IA-0004,ANITI,Artificial and Natural Intelligence Toulouse Institute(2019), ANR-11-LABX-0040,CIMI,Centre International de Mathématiques et d'Informatique (de Toulouse)(2011), European Project: 813211,H2020-EU.1.3. - EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions (Main Programme), H2020-EU.1.3.1. - Fostering new skills by means of excellent initial training of researchers ,10.3030/813211,POEMA(2019), IMFM, Univerza v Ljubljani, Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), and European Project: 813211,H2020,POEMA(2019)
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Nuclear and High Energy Physics ,Polynomial ,Optimization problem ,Trace (linear algebra) ,FOS: Physical sciences ,[MATH.MATH-FA]Mathematics [math]/Functional Analysis [math.FA] ,01 natural sciences ,[MATH.MATH-MP]Mathematics [math]/Mathematical Physics [math-ph] ,0103 physical sciences ,ComputingMethodologies_SYMBOLICANDALGEBRAICMANIPULATION ,Real algebraic geometry ,FOS: Mathematics ,0101 mathematics ,Quantum information ,010306 general physics ,Mathematics - Optimization and Control ,Mathematical Physics ,Flatness (mathematics) ,Mathematics ,Mathematics::Operator Algebras ,010102 general mathematics ,Statistical and Nonlinear Physics ,Mathematical Physics (math-ph) ,Operator theory ,Noncommutative geometry ,Functional Analysis (math.FA) ,Mathematics - Functional Analysis ,Algebra ,46N50, 90C22, 47N10, 13J30 ,Optimization and Control (math.OC) ,[MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC] - Abstract
Motivated by recent progress in quantum information theory, this article aims at optimizing trace polynomials, i.e., polynomials in noncommuting variables and traces of their products. A novel Positivstellensatz certifying positivity of trace polynomials subject to trace constraints is presented, and a hierarchy of semidefinite relaxations converging monotonically to the optimum of a trace polynomial subject to tracial constraints is provided. This hierarchy can be seen as a tracial analog of the Pironio, Navascu\'es and Ac\'in scheme [New J. Phys., 2008] for optimization of noncommutative polynomials. The Gelfand-Naimark-Segal (GNS) construction is applied to extract optimizers of the trace optimization problem if flatness and extremality conditions are satisfied. These conditions are sufficient to obtain finite convergence of our hierarchy. The results obtained are applied to violations of polynomial Bell inequalities in quantum information theory. The main techniques used in this paper are inspired by real algebraic geometry, operator theory, and noncommutative algebra., Comment: 32 pages
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- 2020
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33. Research of driver's perception of novel traffic signals using an eye tracker
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Pliego Prim, Ignacio, Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, Van Wunnik, Lucas Philippe, Ambrož, Miha, and Kunc, Robert
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Traffic engineering ,Enginyeria mecànica [Àrees temàtiques de la UPC] ,Eye -- Movements ,Traffic signs and signals ,Senyalització viària ,Ulls -- Moviments ,Eye tracker, Dikablis system, Gaze, Driving behavior, Area of interest, Traffic signals, Road safety ,Enginyeria del trànsit - Abstract
Novo Mesto is a small town in the Slovenian countryside which is undergoing a new project of road safety. New traffic signals are to be placed in bus stops to give drivers awareness of children standing waiting for the bus. Our mission is to use an eye tracker (the Dikablis device by Ergoneers) to study the reaction of three test drivers against these new signals; if they do detect them or not and if they modify their driving behavior once noticed them. The methodology is to do a first test before the signal placements and another one after, and afterwards compare both situations. Results are satisfying, with high values of reliability, and make us think the new signals will be useful and will contribute to make the road a safer place for children. Outgoing
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- 2019
34. Experimental study of threshold of movement in high slope streams in order to analyze flood risk assesment in mountain rivers
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Lin, Chien-Chih, Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, Technische Universiteit Delft, Technische Universität Dresden, Univerza v Ljubljani, Bateman Pinzón, Allen, Medina Iglesias, Vicente César de, and Bhattacharya, Biswa
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Enginyeria civil [Àrees temàtiques de la UPC] ,Sediments (Geologia) -- Transport ,mountain rivers ,Shields diagram ,flood risk ,Sediment transport - Abstract
In order to improve our knowledge of the behaviour of Rivers Mountains and the risk associated to them, this TFM propose to study experimentally the morphodynamic behaviour of these rivers under avenue situation. The consequences of floods in High Mountain rivers are complex because the high slopes and the scour of the banks. Those processes studied superficially until today. The aim of the present work is to understand deeply those processes understanding the threshold of motion in high slopes rivers and the influence of it in the study of floods. Incoming
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- 2019
35. Design of a bending beam for manufacturing with additive technologies
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Mendieta Pons, Pau, Universitat Politècnica de Catalunya. Departament d'Organització d'Empreses, Univerza v Ljubljani, Van Wunnik, Lucas Philippe, and Klemenc, Jernej
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Enginyeria mecànica [Àrees temàtiques de la UPC] ,Industrial efficiency ,Eficiència industrial - Abstract
Prototyping or materialisation is an expensive stage of Product Design. In a lot of cases, the same technology is both used for the final product and test models; this makes the prototype units very expensive. The use of Additive Manufacturing to build prototypes and small lot parts might be incredibly useful in the future, reducing costs drastically. On the other hand, a large number of units should be build using ordinary methods, being more efficient when it comes to Mass Production. In this thesis, the limitations of Additive Manufacturing are faced creating a method that allows the production of semi-hollow parts. Depending on the AM Technology used and its own limitations, different geometries and parameters may change, allowing the part to be more or less hollow. However, the AM method designed would be the same. The current method has been tested using Fused Deposition Modelling Technology on PLA plastic. The bending beams were successfully printed and tested, giving good results and repeatability. Moreover, having determined that it works on FDM, the same method could be used for Powder Bed Fusion Technology and other AM Technologies.
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- 2019
36. Metode za porušno analizo masivnih konstrukcijskih elementov
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Stanic, Andjelka, Roberval (Roberval), Université de Technologie de Compiègne (UTC), Université de Technologie de Compiègne, Univerza v Ljubljani, Adnan Ibrahimbegovic, Bostjan Brank, and Brank, Boštjan
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Finite element method ,Failure analysis ,finite element method ,analyse à rupture ,localized failure ,discontinuité forte ,Rupture localisée ,Path-following method ,path-following method ,gradbeništvo ,porušna analiza ,metoda sledenja ravnotežne poti ,disertacije ,Méthode de continuation ,vgrajena nezveznost ,Analyse à rupture ,thesis ,embedded discontinuity ,méthode de continuation ,Localized failure ,[SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph] ,failure analysis ,Fissures ,Embedded discontinuity ,building environment ,udc:519.876.5:624.012:624.07(043) ,méthode des éléments finis ,Discontinuité forte ,civil engineering ,grajeno okolje ,metoda končnih elementov ,rupture localisée ,lokalizirana porušitev - Abstract
The thesis studies: the methods for failure analysis of solids and structures, and the embedded strong discontinuity finite elements for modelling material failures in quasi brittle 2d solids. As for the failure analysis, the consistently linearized path-following method with quadratic constraint equation is first presented and studied in detail. The derived path-following method can be applied in the nonlinear finite element analysis of solids and structures in order to compute a highly nonlinear solution path. However, when analysing the nonlinear problems with the localized material failures (i.e. materialsoftening), standard path-following methods can fail. For this reason we derived new versions of the pathfollowing method, with other constraint functions, more suited for problems that take into account localized material failures. One version is based on adaptive one-degree-of-freedom constraint equation, which proved to be relatively successful in analysing problems with the material softening that are modelled by the embedded-discontinuity finite elements. The other versions are based on controlling incremental plastic dissipation or plastic work in an inelastic structure. The dissipation due to crack opening and propagation, computed by e.g. embedded discontinuity finite elements, is taken into account. The advantages and disadvantages of the presented path-following methods with different constraint equations are discussed and illustrated on a set of numerical examples. As for the modelling material failures in quasi brittle 2d solids (e.g. concrete), several embedded strong discontinuity finite element formulations are derived and studied. The considered formulations are based either on: (a) classical displacement-based isoparametric quadrilateral finite element or (b) on quadrilateral finite element enhanced with incompatible displacements. In order to describe a crack formation and opening, the element kinematics is enhanced by four basic separation modes and related kinematic parameters. The interpolation functions that describe enhanced kinematics have a jump in displacements along the crack. Two possibilities were studied for deriving the operators in the local equilibrium equations that are responsible for relating the bulk stresses with the tractions in the crack. For the crack embedment, the major-principle-stress criterion was used, which is suitable for the quasi brittle materials. The normal and tangential cohesion tractions in the crack are described by two uncoupled, nonassociative damage-softening constitutive relations. A new crack tracing algorithm is proposed for computation of crack propagation through the mesh. It allows for crack formation in several elements in a single solution increment. Results of a set of numerical examples are provided in order to assess the performance of derived embedded strong discontinuity quadrilateral finite element formulations, the crack tracing algorithm, and the solution methods.; Objectifs de la thèse : l’analyse à rupture de structure de type solides et membranes et la modélisation de la rupture quasi-fragile par la méthode des éléments finis à forte discontinuité en cas de solide 2D. Dans ce travail, la méthode de continuation avec une équation de contrainte quadratique est présentée sous sa forme linéarisée. En présence de ruptures locales, la méthode de continuation standard peut échouer. Afin d’améliorer la performance de cette méthode, nous proposons de nouvelles versions plus sophistiquées qui prennent en compte les ruptures locales des matériaux. D’une part, une version est basée sur une équation supplémentaire adaptative imposant une limitation. Cette version est considérée relativement satisfaisante pour les matériaux adoucissants. D’autres versions sont basées sur le contrôle de la dissipation incrémentale pour les matériaux inélastiques. Plusieurs formulations d’éléments finis à forte discontinuité sont présentées en détails pour l’analyse de rupture quasi-fragile. Les approximations discrètes du champ de déplacement sont basées sur des éléments quadrilatéraux isoparamétriques ou des éléments quadrilatéraux enrichis par la méthode des modes incompatibles. Afin de décrire la formation d’une fissure ainsi que son ouverture, la cinématique de l’élément est enrichie par quatre modes de séparation et des paramètres cinématiques. On a également proposé un nouvel algorithme de repérage de fissure pour l’évaluation de la propagation de la fissure à travers le maillage. Plusieurs exemples numériques sont réalisés afin de montrer la performance de l’élément quadrilatéral à forte discontinuité ainsi que l’algorithme de repérage de fissure proposé.; Doktorska disertacija obravnava: (i) metode za porušno analizo trdnih teles in konstrukcij, ter (ii) končne elemente z vgrajeno močno nezveznostjo za modeliranje materialne porušitve v kvazi krhkih 2d trdnih telesih. Za porušno analizo smo najprej preučili konsistentno linearizirano metodo sledenja ravnotežne poti skvadratno vezno enačbo (metoda krožnega loka). Metoda omogoča izračun analize nelinearnih modelov, ki imajo izrazito nelinearno ravnotežno pot. Kljub temu standardne metode sledenja poti lahko odpovedo,kadar analiziramo nelinearne probleme z lokalizirano materialno porušitvijo (mehčanje materiala). Zatosmo izpeljali nove različice metode sledenja poti z drugimi veznimi enačbami, ki so bolj primerne zaprobleme z lokalizirano porušitvijo materiala. Ena različica temelji na adaptivni vezni enačbi, pri katerivodimo izbrano prostostno stopnjo. Izkazalo se je, da je metoda relativno uspešna pri analizi problemov zmaterialnim mehčanjem, ki so modelirani s končnimi elementi z vgrajeno nezveznostjo. Druge različicetemeljijo na kontroli plastične disipacije ali plastičnega dela v neelastičnem trdnem telesu ali konstrukciji.Upoštevana je tudi disipacija zaradi širjenja razpok v elementih z vgrajeno nezveznostjo. Prednosti inslabosti predstavljenih metod sledenja ravnotežnih poti z različnimi veznimi enačbami so predstavljeni naštevilnih numeričnih primerih. Za modeliranje porušitve materiala v kvazi krhkih 2d trdnih telesih (npr. betonskih) smo izpeljali različne formulacije končnih elementov z vgrajeno močno nezveznostjo v pomikih. Obravnavane formulacije temeljijo bodisi (a) na klasičnem izoparametričnem štirikotnem končnem elementu bodisi (b) na štirikotnem končnem elementu, ki je izboljšan z nekompatibilnimi oblikami za pomike. Nastanek in širjenje razpoke opišemo tako, da kinematiko v elementu dopolnimo s štirimi osnovnimi oblikami širjenja razpoke in pripadajočimi kinematičnimi parametri. Interpolacijske funkcije, ki opisujejo izboljšano kinematiko, zajemajo skoke v pomikih vzdolž razpoke. Obravnavali smo dva načina izpeljave operatorjev, ki nastopajo v lokalni ravnotežni enačbi in povezujejo napetosti v končnem elementu z napetostmi na vgrajeni nezveznosti. Kriterij za vstavitev nezveznosti (razpoke) temelji na kriteriju največje glavne napetosti in je primeren za krhke materiale. Normalne in tangentne kohezijske napetosti v razpoki opišemo z dvema nepovezanima, poškodbenima konstitutivnima zakonoma za mehčanje. Predlagamo novi algoritem za sledenje razpoki za izračun širjenja razpoke v mreži končnih elementov. Algoritem omogoča formacijo razpok v več končnih elementih v enem obtežnem koraku. Izračunali smo številne numerične primere, da bi ocenili delovanje izpeljanih formulacij štirikotnih končnih elementov z vgrajeno nezveznostjo in algoritma za sledenje razpoki kot tudi delovanje metod sledenja ravnotežnih poti.
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- 2017
37. A mesh adaptivity scheme on the Landau–de Gennes functional minimization case in 3D, and its driving efficiency
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Iztok Bajc, Slobodan źumer, Frédéric Hecht, Univerza v Ljubljani, Laboratoire Jacques-Louis Lions (LJLL), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Algorithms and parallel tools for integrated numerical simulations (ALPINES), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Mathématiques et de leurs Interactions (INSMI)-Inria de Paris, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), and Jozef Stefan Institute [Ljubljana] (IJS)
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Hessian matrix ,Mathematical optimization ,Physics and Astronomy (miscellaneous) ,Computer science ,Finite elements ,FOS: Physical sciences ,010103 numerical & computational mathematics ,Condensed Matter - Soft Condensed Matter ,PDE ,01 natural sciences ,Mathematics::Numerical Analysis ,3D mesh adaptivity ,symbols.namesake ,0103 physical sciences ,FOS: Mathematics ,Applied mathematics ,Polygon mesh ,Mathematics - Numerical Analysis ,0101 mathematics ,010306 general physics ,Mathematical Physics ,Energy functional ,ComputingMethodologies_COMPUTERGRAPHICS ,[PHYS]Physics [physics] ,Numerical Analysis ,Applied Mathematics ,Mathematical Physics (math-ph) ,Numerical Analysis (math.NA) ,Computational Physics (physics.comp-ph) ,Finite element method ,Computer Science Applications ,Computational Mathematics ,Nonlinear system ,Nematic liquid crystals ,Modeling and Simulation ,symbols ,Method of steepest descent ,Soft Condensed Matter (cond-mat.soft) ,A priori and a posteriori ,Metrics ,Minification ,Nonlinear analysis ,Physics - Computational Physics - Abstract
This paper presents a 3D mesh adaptivity strategy on unstructured tetrahedral meshes by a posteriori error estimates based on metrics derived from the Hessian of a solution. The study is made on the case of a nonlinear finite element minimization scheme for the Landau-de Gennes free energy functional of nematic liquid crystals. Newton's iteration for tensor fields is employed with steepest descent method possibly stepping in.Aspects relating the driving of mesh adaptivity within the nonlinear scheme are considered. The algorithmic performance is found to depend on at least two factors: when to trigger each single mesh adaptation, and the precision of the correlated remeshing. Each factor is represented by a parameter, with its values possibly varying for every new mesh adaptation. We empirically show that the time of the overall algorithm convergence can vary considerably when different sequences of parameters are used, thus posing a question about optimality.The extensive testings and debugging done within this work on the simulation of systems of nematic colloids substantially contributed to the upgrade of an open source finite element-oriented programming language to its 3D meshing possibilities, as also to an outer 3D remeshing module.
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- 2016
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38. Sums of Hermitian Squares and the BMV Conjecture
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Igor Klep, Markus Schweighofer, IMFM, Univerza v Ljubljani, Institut de Recherche Mathématique de Rennes ( IRMAR ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -AGROCAMPUS OUEST-École normale supérieure - Rennes ( ENS Rennes ) -Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institut National des Sciences Appliquées ( INSA ) -Université de Rennes 2 ( UR2 ), Université de Rennes ( UNIV-RENNES ) -Centre National de la Recherche Scientifique ( CNRS ), Supported by the DFG grant ``Barrieren'., Institut de Recherche Mathématique de Rennes (IRMAR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École normale supérieure - Rennes (ENS Rennes)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-INSTITUT AGRO Agrocampus Ouest, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
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[ MATH.MATH-OC ] Mathematics [math]/Optimization and Control [math.OC] ,Polynomial ,Trace (linear algebra) ,[MATH.MATH-OA]Mathematics [math]/Operator Algebras [math.OA] ,010103 numerical & computational mathematics ,Positive-definite matrix ,01 natural sciences ,Combinatorics ,Matrix (mathematics) ,FOS: Mathematics ,trace inequality ,[ MATH.MATH-OA ] Mathematics [math]/Operator Algebras [math.OA] ,Symmetric matrix ,ddc:510 ,0101 mathematics ,Algebraic number ,Operator Algebras (math.OA) ,Mathematics - Optimization and Control ,Mathematical Physics ,Mathematics ,Semidefinite programming ,Mathematics::Operator Algebras ,010102 general mathematics ,semide nite programming ,Mathematics - Operator Algebras ,sum of hermitian squares ,Statistical and Nonlinear Physics ,semidefinite programming ,Hermitian matrix ,Optimization and Control (math.OC) ,11E25, 13J30, 15A90 ,MSC 2000 Primary 11E25, 13J30, 15A90 ,Secondary 15A45, 08B20, 90C22 ,[MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC] ,Bessis-Moussa-Villani (BMV) conjecture - Abstract
Recently Lieb and Seiringer showed that the Bessis-Moussa-Villani conjecture from quantum physics can be restated in the following purely algebraic way: The sum of all words in two positive semidefinite matrices where the number of each of the two letters is fixed is always a matrix with nonnegative trace. We show that this statement holds if the words are of length at most 13. This has previously been known only up to length 7. In our proof, we establish a connection to sums of hermitian squares of polynomials in noncommuting variables and to semidefinite programming. As a by-product we obtain an example of a real polynomial in two noncommuting variables having nonnegative trace on all symmetric matrices of the same size, yet not being a sum of hermitian squares and commutators., 21 pages; minor changes; a companion Mathematica notebook is now available in the source file
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- 2008
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39. Jezikovna politika v Ukrajini 1991–2014
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Marija Sotnikova Štravs and Univerza v Ljubljani.
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sytuacja językowa ,Ukraina ,jezikovna politika ,Ukrajina ,jezikovna situacija ,polityka językowa - Abstract
Recenzowany tom jest pokłosiem konferencji zorganizowanej w dniach 24–25 października przez Koło Naukowe Glottodydaktyków, działające przy Katedrze Lingwistyki Stosowanej i Kulturowej UŁ. Organizatorzy konferencji zaproponowali bardzo atrakcyjny i ważny temat, który zainspirował jej uczestników do przygotowania artykułów skupionych wokół trzech grup zagadnień: dydaktyki języka, lingwistyki kulturowej i dialektologii. Ogromnie cieszy zainteresowanie młodych naukowców tematyką dydaktyczną i glottodydaktyczną oraz kulturową. Zamieszczone w tomie artykuły pokazują poszukiwania nowych metod nauczania, przy znajomości dotychczasowych osiągnięć w tej dziedzinie, w oparciu o wiedzę językoznawczą i z wykorzystaniem technologii informacyjnych. Cykliczne organizowanie takich konferencji jest ważną i cenną inicjatywą młodych językoznawców, dydaktyków i kulturoznawców.
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- 2015
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40. HIDROGEOLOGIJA ZGORNJE SOŠKE NIŽINE
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Zini, Luca, Cucchi, Franco, Treu, Francesco, Biolchi, Sara, Boccali, Chiara, Cleva, Silvia, Zavagno, Enrico, Borga, Marco, Marra, Francesco, Zoccatelli, Davide, Zuecco, Giulia, Fazzini, Massimiliano, Russo, Sabrina, Vaccaro, Carmela, Inštitut za raziskovanje krasa ZRC SAZU, Nacionalni laboratorij za zdravje, okolje in hrano (Lokacija Nova Gorica), Geologija d.o.o. Idrija (zunanji izvajalec VP), Naravoslovnotehniška fakulteta, Univerza v Ljubljani (zunanji izvajalec VP), Zini, Luca, Cucchi, Franco, Treu, Francesco, Biolchi, Sara, Boccali, Chiara, Cleva, Silvia, Zavagno, Enrico, Borga, Marco, Marra, Francesco, Zoccatelli, Davide, Zuecco, Giulia, Fazzini, Massimiliano, Russo, Sabrina, and Vaccaro, Carmela
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GEP Projekt ,GIS ,hidrogeologija ,GEP Projekt, hidrogeologija, GIS - Abstract
Namen projekta »Skupni geoinformacijski sistem za varovanje virov pitne vode v izrednih dogodkih (GEP)« je vzpostaviti enoten čezmejni sistem ukrepanja civilne zaščite v primeru ogroženosti virov pitne vode zaradi tehnološkega tveganja in naravnih nesreč na območju Gorenjske, Goriške in Obalno– kraške statistične regije v Sloveniji ter Avtonomne dežele Furlanije-Julijske krajine v Italiji. Za pripravo ustreznih načrtov ukrepanja je potrebno upoštevati hidrogeološke in hidrološke značilnosti območja v prispevnem zaledju vodnih virov. Od teh je namreč odvisno, na kakšen način in v kakšnem obsegu se bo morebitno onesnaženje širilo proti vodnim virom in v kolikšni meri bo ogrozilo njihovo kakovost. Pomembna pridobitev projekta je hidrogeološka nadgradnja GIS-a virov pitne vode na osnovi skupnih čezmejnih hidrogeoloških raziskav z metodami kartiranja ranljivosti in numeričnega modeliranja za kraški vodonosnik Trnovsko–Banjške planote in aluvialni vodonosnik Soške nižine, ki sta glavna skupna vira pitne vode. Zbrane podatke smo povezali v hidrogeološki model, ki povzema značilnosti pretakanja vode in širjenja onesnaženja ter ga vključili v obstoječi GIS. Ta omogoča, da lahko v primeru onesnaženja na določeni lokaciji takoj ocenimo, kateri vodni viri so ogroženi in kdaj najprej lahko pričakujemo pojav onesnaženja v njih. Da bi lahko onesnaženje pravočasno zaznali, je potrebno na ogroženih vodnih virih vzpostaviti monitoring kakovosti. Pri njegovem načrtovanju moramo upoštevati hidrogeološke značilnosti območja in izvajanje sproti prilagajati trenutnim hidrološkim razmeram. Podane so osnovne smernice za spremljanje kakovosti vodnih virov ob izrednih dogodkih. Izdelani GIS omogoča, da lahko tudi osebe, ki niso strokovnjaki na področju hidrogeologije, enostavno in hitro pridejo do prvih informacij o ogroženosti virov pitne vode ob izrednih dogodkih ter jih upoštevajo pri načrtovanju takojšnjega ukrepanja. V naslednjih fazah pa je za bolj podrobno analizo nastalih razmer in optimizacijo ukrepov zelo koristno sodelovanje hidrogeologov. V okviru projekta smo izvedli tudi prostorsko analizo, pri kateri smo upoštevali vse človekove dejavnosti, ki lahko vplivajo na kakovost vodnih virov. Analiza je privedla do poznavanja najpomembnejših onesnaževalcev in najbolj občutljivih območij v Soški nižini. Kot primer pravilnega upravljanja z okoljem smo pripravili alternativni scenarij, ki bi na podlagi ekonomsko in ekološko izvedljivih ukrepov lahko pripeljal do izboljšanja trenutnega stanja. Postavljen je bil geoinformacijski sistem (GIS) projekta GEP, ki vključuje zbrane podatke o vodnih virih na obravnavanem območju.
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- 2014
41. Application of heterogeneous fenton oxidation for the removal of pollutants from wastewater
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Rodríguez Rey, Daniel, Univerza v Ljubljani, Van Wunnik, Lucas Philippe, and Žgajnar Gotvajn, Andreja
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Heterogeneous catalysis ,Sewage -- Purification ,Enginyeria química::Química del medi ambient [Àrees temàtiques de la UPC] ,Electrolytic oxidation -- Industrial applications ,Fenton oxidation ,Aigües residuals -- Depuració ,Oxidació electrolítica -- Aplicacions industrials ,Advanced oxidation process ,Wastewater - Abstract
During the last century there has been a growing concern about water pollution throughout the developed countries. Water has a major impact on the environment as it is used by all living being. This leads to leave the wastewater used with an acceptable quality for its next destination. Fortunately, national and international water quality agreements and laws have pushed development of wastewater treatment technology that nowadays allows us to return the used water to the environment in good conditions. Nevertheless, more modern and simpler technologies should be researched in order to make wastewater treatment a process reachable all around the world within the minimum environmental impact and minimizing waste. This thesis researches one of the technologies with more future in this field; the Fenton process, a reaction that belongs to the Advanced Oxidation Processes (AOPs). The aim of this thesis is to optimise the Fenton reaction. This has been done by testing different catalysts, concentration of chemicals, and operational conditions. In this context, the experiments performed in the frame of this study have explored: - The feasibility of the iron/iron oxide catalyst. - The optimum reactive conditions for the heterogeneous Fenton process; the reaction pH, concentration of the H2O2 and temperature. - The optimal preparation of the catalyst in terms of its level of oxidation and Its potentials or limitations in applied Fenton process. Towards the checking of these parameters the experiments were conducted using propionic acid (PA) as a model of organic substance with nine different iron oxide catalysts in order to simulate a wastewater sample under the Fenton’s reaction and with a regular checking of the amount of total organic carbon (TOC) with time. Obtained results showed good process efficiency near to 50% of TOC removal, working at a smoothly acid pH and without remarkable iron leaching at 60 ºC and an excess of H2O2.
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- 2014
42. The tracial moment problem and trace-optimization of polynomials
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Igor Klep, Kristijan Cafuta, Sabine Burgdorf, Janez Povh, Université de Neuchâtel, Institut de Recherche Mathématique de Rennes ( IRMAR ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -AGROCAMPUS OUEST-École normale supérieure - Rennes ( ENS Rennes ) -Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institut National des Sciences Appliquées ( INSA ) -Université de Rennes 2 ( UR2 ), Université de Rennes ( UNIV-RENNES ) -Centre National de la Recherche Scientifique ( CNRS ), Fakulteta za naravoslovje in matematiko, Univerza v Mariboru, Fakulteta za matematiko in fiziko, Univerza v Ljubljani, Faculty of logistics [Slovenia], University of Maribor, Université de Neuchâtel (UNINE), Institut de Recherche Mathématique de Rennes (IRMAR), AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École normale supérieure - Rennes (ENS Rennes)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-INSTITUT AGRO Agrocampus Ouest, and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)
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Polynomial ,Trace (linear algebra) ,Optimization problem ,General Mathematics ,MathematicsofComputing_NUMERICALANALYSIS ,0211 other engineering and technologies ,02 engineering and technology ,01 natural sciences ,Matrix (mathematics) ,0101 mathematics ,sum of squares ,ComputingMilieux_MISCELLANEOUS ,Mathematics ,free positivity ,[ INFO.INFO-RO ] Computer Science [cs]/Operations Research [cs.RO] ,Discrete mathematics ,Semidefinite programming ,noncommutative polynomial ,021103 operations research ,010102 general mathematics ,[INFO.INFO-RO]Computer Science [cs]/Operations Research [cs.RO] ,semidefinite programming ,Hermitian matrix ,Moment problem ,flat extension ,real algebraic geometry ,90C22, 13J30, 47A57, 08B20 ,Relaxation (approximation) ,Software ,tracial moment problem - Abstract
The main topic addressed in this paper is trace-optimization of polynomials in noncommuting (nc) variables: given an nc polynomial f, what is the smallest trace $${f(\underline {A})}$$ can attain for a tuple of matrices $${\underline {A}}$$ ? A relaxation using semidefinite programming (SDP) based on sums of hermitian squares and commutators is proposed. While this relaxation is not always exact, it gives effectively computable bounds on the optima. To test for exactness, the solution of the dual SDP is investigated. If it satisfies a certain condition called flatness, then the relaxation is exact. In this case it is shown how to extract global trace-optimizers with a procedure based on two ingredients. The first is the solution to the truncated tracial moment problem, and the other crucial component is the numerical implementation of the Artin-Wedderburn theorem for matrix *-algebras due to Murota, Kanno, Kojima, Kojima, and Maehara. Trace-optimization of nc polynomials is a nontrivial extension of polynomial optimization in commuting variables on one side and eigenvalue optimization of nc polynomials on the other side—two topics with many applications, the most prominent being to linear systems engineering and quantum physics. The optimization problems discussed here facilitate new possibilities for applications, e.g. in operator algebras and statistical physics.
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- 2013
- Full Text
- View/download PDF
43. Polish and Slovene devil is not as black…
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Wtorkowska, Maria and Univerza v Ljubljani
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teaching Polish as a foreign language ,comparative phraseology ,frazeologia porównawcza ,glottodydaktyka polonistyczna ,język polski jako obcy (JPJO) ,Polish as a foreign language - Abstract
Artykuł poświęcony jest frazeologii porównawczej. Porównano w nim związki frazeologiczne znajdujące się w podręczniku E. Rybickiej Nie taki diabeł straszny… Podręcznik frazeologii dla obcokrajowców ze związkami wyrazowymi występującymi w języku słoweńskim. Podstawą podziału materiału było kryterium formalno-znaczeniowe oraz kulturowe – zbadano, które z tych związków mają taką samą, podobną, czy inną strukturę, które znaczą to samo lub co innego i jaki jest ich zakres użycia w obu językach. The article deals with comparative phraseology. It compares phraseological units which can be found in the textbook Nie taki diabeł straszny… Podręcznik frazeologii dla obcokrajowców [The devil is not as black…Textbook of phraseology for foreigners] by E. Rybicka with the corresponding Slovene phraseological units. The main criterion for the division was that of formal and semantic correspondence, based on the semantics and the structural form of the phraseological equivalent. We examined which of the phraseological units have identical, similar or different structure, which carry the same or different meaning and what is the scope of their usage in both languages. The comparative analysis demonstrated three main types of equivalency – full, partial and substitutionary.
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- 2013
44. Thermal fatigue of high chromium steel rolls
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Valverde Montraveta, Gerard, Fajfar, Peter, and Univerza v Ljubljani
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Enginyeria dels materials::Metal·lúrgia [Àrees temàtiques de la UPC] ,Finite element method ,Chromium steel -- Cracking ,Enginyeria dels materials::Assaig de materials::Assaig de fractura [Àrees temàtiques de la UPC] ,Acer al crom -- Fissuració ,Elements finits, Mètode dels ,Rolling (Metal-work) ,Acer al crom -- Propietats tèrmiques ,Chromium steel -- Thermal properties ,Laminatge (Metal·lúrgia) ,Matemàtiques i estadística::Anàlisi numèrica::Mètodes en elements finits [Àrees temàtiques de la UPC] - Abstract
Within the master work the phenomenon of appearance of firecracks on the surface of the work rolls that occur during hot rolling of flat products in the case of regular rolling conditions and in the case of the rolling mill stalls was investigated. During hot rolling work rolls are subjected to successive heating and cooling conditions. Their surface is exposed to rapid temperature changes due to the contact with hot rolled material and due to cold water used for rolls cooling. These cyclic heating/cooling conditions cause thermal fatigue which is one of the most important factors affecting the rate of surface deterioration as well as mechanical fatigue and abrasion. Two different tests for the laboratory assessments of the thermal fatigue resistance of the high-chromium steel rolls were used. The first test enables a simulation of the work roll thermal fatigue in the case of regular rolling conditions. Furthermore, with the second test thermal fatigue of work rolls in the case of the rolling mill stalls was investigated. Both tests were implemented in a thermo-mechanical simulator of metallurgical states, the Gleeble 1500D. Finite elements method simulations were performed to determinate the temperature distribution in the work rolls by using NSC.SuperForm software. Evident dependence of the crack nucleation and their growth with the temperature and the cooling medium was found but no dependence due to the length of contact time was found. The influence of slab thickness and slab initial temperature to the temperature evolution in the surface layer of the work roll was estimated. The master work contributes to better understanding of crack nucleation and their growth during the usual hot rolling conditions, as well as for the case of rolling mill stalls. Outgoing
- Published
- 2013
45. The impact of self-similarity on queues utilitzation
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Perez Jorge, Nicolas, Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Univerza v Ljubljani, and Zemva, Andrej
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self-similarity ,Autosimilar ,DiffServ ,TCP/IP (Protocol de xarxes d'ordinadors) ,Opnet modeler ,Enginyeria de la telecomunicació::Telemàtica i xarxes d'ordinadors::Protocols de comunicació [Àrees temàtiques de la UPC] ,Enginyeria de la telecomunicació::Telemàtica i xarxes d'ordinadors::Trànsit de dades [Àrees temàtiques de la UPC] ,Internet -- Protocols ,Videotelefonia ,TCP/IP (Computer network protocol) - Abstract
Projecte final de de carrera fet en col.laboració amb University of Ljubljana. Faculty of Electrical Engineering English: Analysis of the impact of traffic self-similarity on queues utilization of a telecommunication network's device through the software tool Opnet modeler. Castellano: Análisis del impacto del tráfico autosimilar en la utilización de una cola de un dispositivo de una red de telecomunicaciones mediante el simulador Opnet modeler. Català: Anàlisi de l'mpacte del tràfic autosimilar en la utilizació d'una cua d'un dispositiu que pertany a una xarxa de telecomunicacions mitjançant el software Opnet modeler.
- Published
- 2011
46. The truncated tracial moment problem
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Burgdorf , Sabine, Klep , Igor, Institut de Recherche Mathématique de Rennes (IRMAR), AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Fachbereich Mathematik und Statistik, University of Konstanz, IMFM, Univerza v Ljubljani, Institut de Recherche Mathématique de Rennes ( IRMAR ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -AGROCAMPUS OUEST-École normale supérieure - Rennes ( ENS Rennes ) -Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institut National des Sciences Appliquées ( INSA ) -Université de Rennes 2 ( UR2 ), Université de Rennes ( UNIV-RENNES ) -Centre National de la Recherche Scientifique ( CNRS ), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École normale supérieure - Rennes (ENS Rennes)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-INSTITUT AGRO Agrocampus Ouest, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), and Guillemer, Marie-Annick
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noncommutative polynomial ,Mathematics::Operator Algebras ,[MATH.MATH-RA]Mathematics [math]/Rings and Algebras [math.RA] ,[MATH.MATH-FA] Mathematics [math]/Functional Analysis [math.FA] ,sum of hermitian squares ,47A57, 15A45, 13J30 (Primary) 08B20, 11E25, 44A60 (Secondary) ,Mathematics - Rings and Algebras ,[ MATH.MATH-FA ] Mathematics [math]/Functional Analysis [math.FA] ,[MATH.MATH-FA]Mathematics [math]/Functional Analysis [math.FA] ,[ MATH.MATH-RA ] Mathematics [math]/Rings and Algebras [math.RA] ,Functional Analysis (math.FA) ,Mathematics - Functional Analysis ,(Truncated) moment problem ,Rings and Algebras (math.RA) ,moment matrix ,[MATH.MATH-RA] Mathematics [math]/Rings and Algebras [math.RA] ,FOS: Mathematics ,47A57, 15A45, 13J30 ,free positivity - Abstract
We present tracial analogs of the classical results of Curto and Fialkow on moment matrices. A sequence of real numbers indexed by words in non-commuting variables with values invariant under cyclic permutations of the indexes, is called a tracial sequence. We prove that such a sequence can be represented with tracial moments of matrices if its corresponding moment matrix is positive semidefinite and of finite rank. A truncated tracial sequence allows for such a representation if and only if one of its extensions admits a flat extension. Finally, we apply the theory via duality to investigate trace-positive polynomials in non-commuting variables., Comment: 21 pages
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- 2010
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47. Trace-positive polynomials and the quartic tracial moment problem Polynômes avec une trace positive et le problème quartique des moments traciaux
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Burgdorf, Sabine, Klep, Igor, Institut de Recherche Mathématique de Rennes ( IRMAR ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -AGROCAMPUS OUEST-École normale supérieure - Rennes ( ENS Rennes ) -Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institut National des Sciences Appliquées ( INSA ) -Université de Rennes 2 ( UR2 ), Université de Rennes ( UNIV-RENNES ) -Centre National de la Recherche Scientifique ( CNRS ), Fachbereich Mathematik und Statistik, University of Konstanz, IMFM, Univerza v Ljubljani, Institut de Recherche Mathématique de Rennes (IRMAR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École normale supérieure - Rennes (ENS Rennes)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-INSTITUT AGRO Agrocampus Ouest, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
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Mathematics::Operator Algebras ,[ MATH.MATH-FA ] Mathematics [math]/Functional Analysis [math.FA] ,[MATH.MATH-FA]Mathematics [math]/Functional Analysis [math.FA] - Abstract
International audience; The tracial analog of Hilbert's classical result on positive binary quartics is presented: a trace-positive bivariate noncommutative polynomial of degree at most four is a sum of hermitian squares and commutators. This is applied via duality to investigate the truncated tracial moment problem: a sequence of real numbers indexed by words of degree four in two noncommuting variables with values invariant under cyclic permutations of the indexes, can be represented with tracial moments of matrices if the corresponding moment matrix is positive definite. Understanding trace-positive polynomials and the tracial moment problem is one of the approaches to Connes' embedding conjecture.
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- 2010
- Full Text
- View/download PDF
48. Les stratégies des locuteurs et la structuration de l'oral spontané en français et en slovène
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Zwitter Vitez, Ana, RFC - Recherche sur le français contemporain - EA 1483 (RFC), Université Sorbonne Nouvelle - Paris 3, Université de la Sorbonne nouvelle - Paris III, Mary-Annick Morel, Vladimir Pogačnik, Univerza v Ljubljani, and STAR, ABES
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Speech paragraph ,Oral spontané ,Stratégies communicatives ,Spontaneous speech ,Analyse du dicours ,Paragraphe oral ,[SHS.LANGUE]Humanities and Social Sciences/Linguistics ,[SHS.LANGUE] Humanities and Social Sciences/Linguistics ,Communication strategies ,Discourse analysis - Abstract
The aims of the present study are to define the unit for the analysis of the spontaneous speech in french and in slovene, to examine the influence of the context elements on the structure of this unit and to analyse the most efficient combinations of the linguistic structures whithin three basic speech strategies: turn taking, seeking for attention and request for reaction. The analysis shows that the basic unit of spontaneaous speech can be defined by simultaneaous fall of intensity and pitch in both languages. This basic unit is defined as speech paragraph with its components preamble, rheme and postrheme. In the next step, the study examines the influence of the context elements on the structuration of the spontaneous spoken discourse. The analysis of the narration, argumentation and confrontation of different opinions shows the influence of the discourse genre on the lenght and the internal structure of the preamble. On the other hand, the speaker's profile seems to have the most important effect on the use of the connectors. The analysis of the speaker's strategies in spontaneous spoken discourse shows that when two speakers start speaking at the same moment and fight for their turns, the speaker who increases the intensity, produces more features of non final formulation will more likely keep or get his turn. When a speaker wants the listener to react in order to confirm his speaking, he will realise a fall of intensity at the end of a syntactic unit, which usually takes place at the end of a rheme., Les buts de la présente étude étaient de délimiter une unité de l'analyse de l'oral spontané comparable en français et en slovène, d'examiner l'influence des éléments contextuels sur la structuration de cette unité et de dégager les combinaisons de structures linguistiques les plus efficaces lors de trois stratégies communicatives de base : lutte pour la parole, appel à l'attention et la demande de réaction. L'analyse a montré que dans les deux langues, l'unité de base de l'oral peut être délimitée par la chute conjointe de l'intensité et de la hauteur tonale. Cette unité, reprise par la méthodologie de Morel et Danon-Boileau [1998] est dénominée le paragraphe oral avec ses constituants préambule, rhème et postrhème. Une fois l'unité de base délimitée, l'étude examine l'influence des éléments contextuels sur la structuration de l'oral spontané. L'analyse de la narration, de l'argumentation et de la confrontation d'opinions différentes a montré surtout l'influence du type du discours sur la longueur du préambule et sur sa composition interne. Le profil des locuteurs semble avoir la plus grande influence sur le choix des ligateurs. En ce qui concerne les stratégies des locuteurs, les résultats montrent que lors de la lutte pour la parole, le locuteur qui produit ses énoncés avec une intensité plus forte et un surplus de marques du travail de formulation va à la fin d'un chevauchement garder la parole. Quand il demande auprès de celui qui l'écoute une réaction, il le réalise par une chute de l'intensité à la fin d'une structure syntaxique, ce qui coïncide avec la fin d'un rhème.
- Published
- 2009
49. Connes' embedding conjecture and sums of hermitian squares
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Igor Klep, Markus Schweighofer, Institut de Recherche Mathématique de Rennes (IRMAR), AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), IMFM, Univerza v Ljubljani, Institut de Recherche Mathématique de Rennes ( IRMAR ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -AGROCAMPUS OUEST-École normale supérieure - Rennes ( ENS Rennes ) -Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institut National des Sciences Appliquées ( INSA ) -Université de Rennes 2 ( UR2 ), Université de Rennes ( UNIV-RENNES ) -Centre National de la Recherche Scientifique ( CNRS ), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École normale supérieure - Rennes (ENS Rennes)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-INSTITUT AGRO Agrocampus Ouest, and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)
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[ MATH.MATH-OC ] Mathematics [math]/Optimization and Control [math.OC] ,Mathematics(all) ,quadratic module ,General Mathematics ,von Neumann algebra ,[MATH.MATH-OA]Mathematics [math]/Operator Algebras [math.OA] ,11E25 ,010103 numerical & computational mathematics ,Connes’ embedding conjecture ,01 natural sciences ,tracial state ,Tracial state ,Separable space ,Combinatorics ,symbols.namesake ,FOS: Mathematics ,[ MATH.MATH-OA ] Mathematics [math]/Operator Algebras [math.OA] ,0101 mathematics ,Algebraic number ,ddc:510 ,sum of squares ,Operator Algebras (math.OA) ,Contraction (operator theory) ,Quadratic module ,Mathematics ,Conjecture ,Mathematics::Operator Algebras ,010102 general mathematics ,Mathematics - Operator Algebras ,Explained sum of squares ,Mathematics - Rings and Algebras ,11E25, 13J30, 58B34 (Primary), 08B20, 47L07, 46L10 (Secondary) ,Hermitian matrix ,Von Neumann algebra ,Rings and Algebras (math.RA) ,symbols ,Embedding ,[MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC] ,Sum of squares ,Connes' embedding conjecture - Abstract
International audience; We show that Connes' embedding conjecture on von Neumann algebras is equivalent to the existence of certain algebraic certificates for a polynomial in noncommuting variables to satisfy the following nonnegativity condition: The trace is nonnegative whenever self-adjoint contraction matrices of the same size are substituted for the variables. These algebraic certificates involve sums of hermitian squares and commutators. We prove that they always exist for a similar nonnegativity condition where elements of separable II1-factors are considered instead of matrices. Under the presence of Connes' conjecture, we derive degree bounds for the certificates
- Published
- 2008
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50. District heating using forestry biomass: Technical feasibility
- Author
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Nobile E., Jodice R., PADOANO, Elio, POZZETTO, DARIO, Univerza V Mariboru - Univerza V Ljubljani, Nobile, E., Padoano, Elio, Pozzetto, Dario, and Jodice, R.
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Renewable sources - Abstract
Il lavoro presenta lo studio di fattibilità tecnica di impianto di teleriscaldamento per una Comunità Montana usando biomassa forestale. Sono presentati i risultati del dimensionamento del sistema di generazione del calore e del sistema di vettoriamento e distribuzione. La procedura utilizzata può essere estesa presso altre realtà territoriali con caratteristiche simili.
- Published
- 1999
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