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Knowing the local variations of the gravity field is a prerequisite for an accurate accelerator alignment in a Euclidean plane, especially for large machines. Within the scope of the Future Circular Collider (FCC), the proposed next-generation particle collider with a circumference of 91 km, efforts are made to compute a local centimetric geoid. Local and global geoid models covering the studied area are not consistent (decimetric differences), so a local solution must be found. To achieve the computation of a centimetric geoid, that will be used for the construction of the tunnel and then refined for the alignment, different methodologies are studied. This paper focuses on the application of the Stokes-Helmert method (Fugro/UNB SHGeo+ package) to compute a local gravimetric geoid. The paper first describes the evaluation of the gravity dataset provided by the BGI (Bureau Gravimétrique International), the IGN (Institut Géographique National) and Swisstopo (Federal Office of Topography). Then the computation of the geoid model is developed, evaluating the influence of lateral rock density variations. Finally, its accuracy is evaluated using a dedicated 40 km geodetic control profile composed of 36 GNSS/levelling stations and 83 deflections of the vertical observations.

Optimal pressure regulation to reduce water losses in water distribution systems (WDSs) becomes an important concern due to the increasing water demand and the threat of drought in many areas of the world. The leakage amount in a WDS depends heavily on its operating pressure and thus can be minimized by implementing optimal pressure strategies through pressure reducing valves (PRVs). To achieve this, a model-based optimization is necessary, where an accurate model of the PRVs is required. The PRV models having been used until now for pressure regulations are two-mode models which cannot circumstantiate many situations occurring in WDSs. In this paper, we extend the existing model by a three-mode one for PRVs which is able to describe the required circumstances of pressure regulations in WDSs. The non-smoothness of this model is smoothed by an approximation approach, thus allowing the formulation and solution of a continuous nonlinear optimization problem for optimal pressure regulation. Two benchmark WDSs are used to verify our approach and it can be shown from the results that our PRV model outperforms the existing models in terms of the quality and accuracy of the optimal solutions.

This paper proposes a static modeling and power flow calculation of the More Electric Aircraft (MEA) power system to study the stability and the fault analysis. Combined with the common land power system, the structure and characteristics of MEA power system are firstly illustrated and the static models are built. Then, on the basis of the alternate iteration method, the method to calculate and analysis the AC/DC hybrid MEA power system is described. Finally, the power flow calculation results and adjust strategy under different working period are showed with an example of Boeing 787. The simulation results showed that the programmed algorithm can accord with the characteristics of MEA power system and the power flow distribution and adjustment strategy are simple and clear.

Building and microgrid designs with highly-distributed electrical storage have potential advantages over today's conventional topologies with centralized storage. This paper studies the capital cost benefits of several residential behind-the-meter distributed-storage topologies, including AC and DC versions of systems with load-packaged batteries and resilient sub-networks. The study begins by defining the block configuration of each topology. This work then develops a model for the cost of the power electronics necessary to interface with the storage elements. Finally, the analysis develops a model for the total cost of each storage topology, incorporating the installation and soft costs. The results suggest that while the cost of power electronics is lower in centralized topologies, the total cost is lower for distributed storage due to the avoided costs of installation and permitting. This paper also explores the benefits of load-packaged batteries for savings in electrical infrastructure.

Energy flexibility, through short-term demand-side management (DSM) and energy storage technologies, is now seen as a major key to balancing the fluctuating supply in different energy grids with the energy demand of buildings. This is especially important when considering the intermittent nature of ever-growing renewable energy production, as well as the increasing dynamics of electricity demand in buildings. This paper provides a holistic review of (1) data-driven energy flexibility key performance indicators (KPIs) for buildings in the operational phase and (2) open datasets that can be used for testing energy flexibility KPIs. The review identifies a total of 81 data-driven KPIs from 91 recent publications. These KPIs were categorized and analyzed according to their type, complexity, scope, key stakeholders, data requirement, baseline requirement, resolution, and popularity. Moreover, 330 building datasets were collected and evaluated. Of those, 16 were deemed adequate to feature building performing demand response or building-to-grid (B2G) services. The DSM strategy, building scope, grid type, control strategy, needed data features, and usability of these selected 16 datasets were analyzed. This review reveals future opportunities to address limitations in the existing literature: (1) developing new data-driven methodologies to specifically evaluate different energy flexibility strategies and B2G services of existing buildings; (2) developing baseline-free KPIs that could be calculated from easily accessible building sensors and meter data; (3) devoting non-engineering efforts to promote building energy flexibility, such as designing utility programs, standardizing energy flexibility quantification and verification processes; and (4) curating datasets with proper description for energy flexibility assessments., Comment: 30 pages, 14 figures, 4 tables

In order to design structures that can withstand anticipated earthquake loads, it is first necessary to understand the behavior of the subsurface when subjected to ground motions. To achieve this, different models and approaches have been proposed in recent decades, each with the aim of estimating how site-specific stratigraphy can amplify and/or scatter seismic waves. All of these methods require, to varying extents, information about the types of soil layers, their thickness, their stiffnesses (represented by a shear wave velocity profile), and lateral variability across the site. This last characteristic is often both difficult and costly to determine. Past research has shown that excluding lateral variability within a model leads to predictions that differ greatly from actual recordings when applying one-dimensional ground response analysis. The purpose of this paper is to analyze a cost-effective approach to incorporate spatial variability in soil stratigraphy by using only one invasively-measured shear wave velocity profile and recordings of ambient noise from numerous receivers distributed on the surface. These receivers aid in the identification of soil column heterogeneity by indicating changes in the fundamental frequency (i.e., the lowest resonant frequency) of a given area with only a few minutes of three-component (two horizontal, one vertical) ambient noise recorded. Once a pseudo-3D shear wave velocity model has been composed, future numerical wave propagation studies can apply the model to better correlate and correct theoretical results to empirical ground motion recordings.

Rad se bavi oblikovanjem cjevovodnih linija upotrebom 3D CAD sustava DS SOLIDWORKS. Cjevovodni sustavi su žile kucavice za transport tvari i proizvoda u gotovo svim industrijama te njihov značaj svakim danom sve više i više raste. Kako bi se proces projektiranja procesnih postrojenja optimizirao, potrebno je koristiti neke od specijaliziranih CAD sustava zbog automatiziranosti postupka. DS SOLIDWORKS je odličan polifunkcionalan 3D alat koji se može koristiti za potrebe svih vrsta industrije. Modul Routing se nalazi unutar SOLIDWORKS Premium paketa, omogućuje brzo i jednostavno konstruiranje cjevovodnih linija. Unutar modula se nalazi baza dostupnih komponenti koje se mogu nadograđivati i aktualizirati paralelno s razvijanjem softvera. Osim posjedovanja softvera i ostalih pomagala za rad, kategorički imperativ svakog inženjera čiji je posao konstruiranje cjevovoda je razumijevanje i primjenjivanje znanja iz materijala, mehanike fluida, termodinamike, informacijskih tehnologija te ostalih polja inženjerstva vezanih uz proces projektiranja cjevovoda. The primary focus of this Bachelor's paper is the 3D modelling of a pipeline. The modelling process is conducted with the 3D CAD software DS SOLIDWORKS. The pipelines are the lifeblood of the transportation process for raw goods and products, they have a monumental role in all parts of industries. Every day onwards, their importance rises more and more. To optimize the designing process of process plants, specialized CAD software must be used due to the high level of automation. DS SOLIDWORKS is a great polyfunctional 3D tool that is used in all branches of the industry. The routing module is part of the SOLIDWORKS Premium package, it enables fast and easy pipeline construction. The module itself has a library that contains many different components which can be upgraded and actualised in parallel with software development. Besides having proper software and other work assistance, proper knowledge and rightful implementation of materials science, fluid mechanics, thermodynamics, IT technologies and other fields of engineering associated with the piping business is a must for every piping engineer.

This paper presents the results of cement-based mortars characterizations that were taken from rendered layers of military bunkers in the Rupnik Line. The Rupnik Line was conceived as a part of the fortified defence system protecting the Rapallo Border between the Kingdom of Italy and the Kingdom of Yugoslavia, established in 1920. The bunkers were built between 1938 and 1941, and the renders of various compositions were applied as a camouflage layer that merged the bunkers with the environment. Results of petrographic examination and microstructural and chemical analysis of the samples confirmed that locally available crushed dolomite or limestone sands were used as an aggregate in the mortars. As binders, pure Portland cement or a mixture of cement and ground granulated blast furnace slag were used. The selection of the aggregate and binder type in a particular mortar was based on the colour of the artificial stone produced. All samples with the dolomite aggregate show the presence of alkali-aggregate reactions, dedolomitization of the grains and secondary calcite formation in the cement binder, along with the Mg-Al, Mg-Si and Mg-Al-Si phase formations. In mortar compositions with a high Portland cement content, the presence of delayed ettringite formation was also confirmed.

An alternative integration scheme for a half-bridge switch using 70 μm thin Si IGBTs and diodes is presented. This flat switch, which is designed for high-frequency application with high power density, exhibits high strength, high toughness, low parasitic inductance and high thermal conductivity. Such a novel assembly approach is suitable to optimize performance, reliability and availability of the power system in which it is used. The paper focuses on the thermal performance of this assembly at normal and extreme operating conditions, studied by means of FEM thermo-fluidynamic simulations of the module integrated with connectors and liquid cooler, and thermal measurement performed on an early prototype. Improved solutions are also investigated by the FE model.

Real-world multi-objective optimization problems encounter different types of uncertainty that may affect the quality of solutions. One common type is the stochastic noise that contaminates the objective functions. Another type of uncertainty is the different forms of dynamism including changes in the objective functions. Although related work in the literature targets only a single type, in this paper, we study Dynamic Multi-objective Optimization problems (DMOPs) contaminated with stochastic noises by dealing with the two types of uncertainty simultaneously. In such problems, handling uncertainty becomes a critical issue since the evolutionary process should be able to distinguish between changes that come from noise and real environmental changes that resulted from different forms of dynamism. To study both noisy and dynamic environments, we propose a flexible mechanism to incorporate noise into the DMOPs. Two novel techniques called Multi-Sensor Detection Mechanism (MSD) and Welford-Based Detection Mechanism (WBD) are proposed to differentiate between real change points and noise points. The proposed techniques are incorporated into a set of Dynamic Multi-objective Evolutionary Algorithms (DMOEAs) to analyze their impact. Our empirical study reveals the effectiveness of the proposed techniques for isolating noise from real dynamic changes and diminishing the noise effect on performance.

With the rising concerns about climate change and technological developments, the deployment of low carbon technologies (LCT) is gaining importance for reliable and sustainable power system operation. To decarbonize the heat and transportation sectors, LCTs such as heat pumps (HP) and electric vehicles (EV) are integrated into the power system from the low voltage (LV) distribution network, where predominantly end-users are connected. However, the increasing penetration of EVs and HPs, together with distributed photovoltaic (PV) systems on the demand side, can cause technical challenges in LV distribution networks, such as under/over voltages at the far end of the feeders. Therefore, the hosting capacity of a grid for LCTs is limited due to network constraints such as line ampacity, bus voltage, and frequency. In this paper, voltage-constrained management approaches for LCTs are proposed to improve the grid hosting capacity in a real large-scale distribution network. Moreover, HPs, PVs, battery energy storage systems (BESS), and EVs as well as their vehicle-to-grid (V2G) feature are evaluated as LCTs. The uncertain behavior of these technologies is taken into consideration for more realistic analyses. In addition, the charging and discharging interactions of BESSs are controlled by following the power consumption profiles from the economic point of view. Furthermore, the hourly carbon data is used to control BESSs from an emission-sensitive aspect. To demonstrate the effectiveness of the proposed algorithms, a series of tests is conducted on a real distribution network model. The results show that the hosting capacity of the considered LV network can be increased from 35% to 50% using the proposed algorithms. The promising results obtained in this study pave the way for future active LCT management studies to improve hosting capacity in urban networks, and pilot demonstrations in the field.

Aluminum has high lithium storage capacity and poor cycle performance as one kind of new advanced material. In this paper, Al64Cu23.5Fe12.5 alloy was prepared by mechanical alloying with pure Al, Cu, and Fe powder as the initial materials and the electrochemical lithium storage performance of AlCuFe ternary alloy was studied. The effects of different milling device and experimental parameters on the microstructure of the alloy were also studied. Magnetic measurement was performed on alloy under different MA state. The results of XRD show that the peak of the elemental phase widens with the increase of the grinding time. New phase appears at about 75 h. It is found that the magnetism of the alloy is weakened with the formation of the new alloy. The discharge capacity of AlCuFe increase with longer milling time. After a long milling time of 100 h in 500 rmp, Al64Cu23.5Fe12.5 alloy exhibites the highest first discharge capacities of 314 mAh g−1. Then the capacity gradually decays in the first 20 cycles and stabilizes at a range of 175–200 mAh g−1, which corresponds to 68% of initial capacity. Compared with pure Al, AlCuFe alloy-show better cycle stability, this facile MA approach provides helpful synergistic effects.

This paper aims to evaluate the effects of blended binders on the development of strength in moraine soils by optimising the proportion of several binders. We tested three types of soil as a mixture of moraine soils: A (sandy clay), B (clayey silt) and C (silty clay), collected in southern Sweden. The soil was compacted using a modified Proctor test using the standard SS-En 13286-2:2010 to determine optimum moisture content. The particle size distribution was analysed to determine suitable binders. The specimens of types A, B and C, were treated by six different binders: ordinary Portland cement (oPC); hydrated lime (Ca(oh) 2); ground granulated blast furnace slag (GGBFS) and their blends in various proportions. The strength gain in soil treated by binders was evaluated by the test for Unconfined Compressive Strength (UCS) against curing time. For soil type A, the strength increase is comparable for most of the binders, with the difference in behaviour in the UCS gain. The oPC/lime, GGBFS and hydrated lime showed a direct correlation, while oPC, oPC/GGBFS and GGBFS/hydrated lime – a quick gain in the UCS by day 28th. After that, the rate of growth decreased. Compared to soil type A, Ca(oh)2 performs better on the stabilisation of soil type B. Besides, the hydrated lime works better on the gain of the UCS compared to other binders. The GGBFS/Ca(oh) 2 blend shows a notable effect on soil type A: the UCS of soil treated by Ca(oh) 2 performs similarly to those treated by oPC with visible effects on day 90 th. Cement and a blend of slag/hydrated lime demonstrated the best results for soil type B. An effective interaction was noted for the blends GGBFS and hydrated lime, which is reflected in the UCS development in soils type A and B. Blended binder GGBFS/hydrated lime performs better compared to single binders.

The purpose of this research paper is to provide infallible proof of a mathematical, physics based, experimental. and anecdotal nature to support the claim that the framework for “Scientific Universal Theory” laid out in this paper represents a functional form of the long sought after Scientific “Theory of Everything”. This paper will emphasize a focus on feasible, non-specious data that is self-aware of the potential for mistakenly identifying a Grand unified scientific framework, and a myriad of comprehensively sufficient logical proofs one may need to assess the validity of this groundbreaking discovery are provided in depth. This grand endeavor seeks to merge the two fundamental pillars of modern physics: quantum mechanics, which governs the behavior of particles at the smallest scales, and general relativity, which describes the nature of gravity and the structure of the cosmos. And in addition to this, which also manages to account for virtually every known branch, field and theorem of science within a singular comprehensive framework which adheres to current accepted math and physics (building upon those things exponentially). This paper aims to explore the profound implications of this theory for society and the world at large, illuminating the revolutionary advances it promises to bring. This research paper/document will be competent, thorough, and aims to provide absolute proof of the functionality of the discovery of this framework, theory and theorem via mathematics calculations, physics data, research data, and examples both anecdotal and experimental. This will include possible demonstrated utilizations of the framework, both from current use of this framework within the scientific community, and feasible indicated uses deduced via comprehensive research. This document aims to create an entourage effect of undeniable evidence to support the functionality of the mathematical and physical principles and discoveries laid out within it. &nbsp

The purpose of this research paper is to provide infallible proof of a mathematical, physics based, experimental. and anecdotal nature to support the claim that the framework for “Scientific Universal Theory” laid out in this paper represents a functional form of the long sought after Scientific “Theory of Everything”. This paper will emphasize a focus on feasible, non-specious data that is self-aware of the potential for mistakenly identifying a Grand unified scientific framework, and a myriad of comprehensively sufficient logical proofs one may need to assess the validity of this groundbreaking discovery are provided in depth. This grand endeavor seeks to merge the two fundamental pillars of modern physics: quantum mechanics, which governs the behavior of particles at the smallest scales, and general relativity, which describes the nature of gravity and the structure of the cosmos. And in addition to this, which also manages to account for virtually every known branch, field and theorem of science within a singular comprehensive framework which adheres to current accepted math and physics (building upon those things exponentially). This paper aims to explore the profound implications of this theory for society and the world at large, illuminating the revolutionary advances it promises to bring. This research paper/document will be competent, thorough, and aims to provide absolute proof of the functionality of the discovery of this framework, theory and theorem via mathematics calculations, physics data, research data, and examples both anecdotal and experimental. This will include possible demonstrated utilizations of the framework, both from current use of this framework within the scientific community, and feasible indicated uses deduced via comprehensive research. This document aims to create an entourage effect of undeniable evidence to support the functionality of the mathematical and physical principles and discoveries laid out within it.

The distribution system is demanded to be more efficient, more flexible and more intelligent due to the continued growth of the electricity loads, the high efficiency of energy utilization and the environmental protection. The traditional distribution systems are facing the challenge of evolving from passive networks to the active distribution networks (ADN) with the integration of multiple controllable resources. This paper presents an optimal operation and schedule model of the ADN, considering a variety of controllable resources such as distributed generations, battery storages and interruptible loads. To solve the optimization problem, a modified fuzzy adaptive PSO assisted by Kriging model (KMA-MFAPSO) is developed in this paper. In KMA-MFPSO, a novel constraint handling technique (CHT) based on the PSO is proposed to handle the constraints effectively. In addition, under the premise of ensuring the accuracy of the calculation, the Kriging model is used in KMA-MFAPSO to calculate the power flow the ADN approximately, which greatly speeds up the solving process. Finally, the effectiveness of the proposed algorithm is tested on a modified IEEE-123 system. The optimal results obtained by the proposed method are compared with the results obtained by using other solving algorithms. The simulation results indicate that KMA-MFAPSO is very robust and fast to solve the optimization problem so that it can be used in practical systems.

In an ESP (English for Specific Purposes) and ELP (English for Legal Purposes) perspective, this paper studies the construction of professional cultural competence through the cultural substrata woven into the narrative of specialised popular fiction, or FASP.After a brief overview of the theoretical framework retained and the functions of a coroner in England and Wales, the discussion focuses on a coronial FASP, M. R. Hall’s The Coroner (2009), to analyse three cultural strands which relate meaningfully to ELP learner objectives: culture specific to the Coroner’s Office, broader social commentary with regard to issues concerning the legal community as a whole and, finally, locus-related societal and national cultures.The paper concludes by addressing reservations expressed regarding such randomly acquired knowledge by highlighting the advantages of a heuristic and semasiological approach in exploring both target and source culture. Dans le cadre de la didactique des langues et cultures spécialisées du droit, cet article porte sur la construction d’une compétence de culture professionnelle à travers les substrats culturels tissés dans la fibre narrative de la fiction populaire spécialisée, la FASP.Après une brève présentation du cadrage théorique retenu, du professionnel de droit qu’est le coroner au Royaume Uni et de la FASP juridique qui constitue l’objet d’étude, The Coroner (2009) de M. R. Hall, l’analyse dégage trois domaines culturels en lien avec les objectifs de l’apprentissage : la culture spécifique à l’environnement spécialisé du professionnel qu’est le coroner, le commentaire social enchâssé dans le récit qui se rapporte à la communauté juridique dans son ensemble et, finalement, les cultures relatives aux lieux qui servent d’ancrage géographique au récit fictif.Pour conclure, l’auteur répond aux réserves souvent exprimées concernant la nature fragmentaire des connaissances acquises par l’intermédiaire de la FASP en mettant en avant les avantages d’une approche heuristique et sémasiologique dans l’exploration des cultures cible et source.

This paper discusses the importance of accurately identifying the parameters and states in permanent magnet synchronous motors (PMSMs) and their impact on motor performance and efficiency. This study was conducted to demonstrate the significance of these parameters. The results showed that inaccurate identification of the friction coefficient and moment of inertia led to poor motor performance, instability, and reduced efficiency. Accurate identification of these parameters is necessary for the proper control and operation of PMSMs. This paper highlights the various methods for calculating the friction coefficient and moment of inertia, as well as their potential limitations. The findings of this study emphasize the importance of accurately identifying these parameters for the efficient and effective operation of PMSMs.

The European normatives prescribe content of 200 mg/Nm(3) NO for pulverized coal combusting power plants. In order to reduce content of NOx in Serbian thermal power plant (TPP) square Kostolac B square its necessary to implement particular measures until 2016. The mathematical model of lignite combustion in the steam boiler furnace is defined and applied to analyze the possibility of implementing certain primary measures for reducing nitrogen oxides and their effects on the steam boiler operation. This model includes processes in the coal-fired furnace and defines radiating reactive two-phase turbulent flow. The model of turbulent flow also contains sub-model of fuel and thermal NOx formation and destruction. This complex mathematical model is related to thermal and aerodynamic calculations of the steam boiler within a unified calculation system in order to analyze the steam boiler overall work. This system provides calculations with a number of influential parameters. The steam boiler calculations for unit 1 (350 MWe) of TPP square Kostolac B square are implemented for existing and modified combustion system in order to achieve effective, reliable and ecological facility work. The paper presents the influence analysis of large number of parameters on the steam boiler operation with an accepted concept of primary measures. Presented system of calculations is verified against measurements in TPP square Kostolac B square. (C) 2015 Elsevier Ltd. All rights reserved.

The proceedings contain the papers submitted to and published at the second RI-STEM international scientific student conference in Rijeka, Croatia.

Regularizing polygons involves simplifying irregular and noisy shapes of built environment objects (e.g. buildings) to ensure that they are accurately represented using a minimum number of vertices. It is a vital processing step when creating/transmitting online digital maps so that they occupy minimal storage space and bandwidth. This paper presents a data-driven and Deep Learning (DL) based approach for regularizing OpenStreetMap building polygon edges. The study introduces a building footprint regularization technique (Poly-GAN) that utilises a Generative Adversarial Network model trained on irregular building footprints and OSM vector data. The proposed method is particularly relevant for map features predicted by Machine Learning (ML) algorithms in the GIScience domain, where information overload remains a significant problem in many cartographic/LBS applications. It addresses the limitations of traditional cartographic regularization/generalization algorithms, which can struggle with producing both accurate and minimal representations of multisided built environment objects. Furthermore, future work proposes a way to test the method on even more complex object shapes to address this limitation.

This paper presents a collaboratively adaptive vibration monitoring system that captures high-fidelity structural vibration signals induced by pedestrians. These signals can be used for various human activities’ monitoring by inferring information about the impact sources, such as pedestrian footsteps, door opening and closing, and dragging objects. Such applications often require high-fidelity (high resolution and low distortion) signals. Traditionally, expensive high resolution and high dynamic range sensors are adopted to ensure sufficient resolution. However, for sensing systems that use low-cost sensing devices, the resolution and dynamic range are often limited; hence this type of sensing methods is not well explored ubiquitously. We propose a low-cost sensing system that utilizes (1) a heuristic model of the investigating excitations and (2) shared information through networked devices to adapt hardware configurations and obtain high-fidelity structural vibration signals. To further explain the system, we use indoor pedestrian footstep sensing through ambient structural vibration as an example to demonstrate the system performance. We evaluate the application with three metrics that measure the signal quality from different aspects: the sufficient resolution rate to present signal resolution improvement without clipping, the clipping rate to measure the distortion of the footstep signal, and the signal magnitude to quantify the detailed resolution of the detected footstep signal. In experiments conducted in a school building, our system demonstrated up to 2× increase on the sufficient resolution rate and 2× less error rate when used to locate the pedestrians as they walk along the hallway, compared to a fixed sensing setting.

As the development of autonomous vehicles rapidly advances, the use of convoying/platooning becomes a more widely explored technology option for saving fuel and increasing the efficiency of traffic. In cooperative adaptive cruise control (CACC), the vehicles in a convoy follow each other under adaptive cruise control (ACC) that is augmented by the sharing of preceding vehicle acceleration through the vehicle to vehicle communication in a feedforward control path. In general, the desired velocity optimization for vehicles in the convoy is based on fuel economy optimization, rather than driveability. This paper is a preliminary study on the impact of the desired velocity profile on the driveability characteristics of a convoy of vehicles and the controller gain impact on the driveability. A simple low-level longitudinal model of the vehicle has been used along with a PD type cruise controller and a generic spacing policy for ACC/CACC. The acceleration of the previous vehicle is available to the next vehicle as input, and the simulations are performed as Cooperative Adaptive Cruise Control of a convoy of vehicles. Individual vehicle acceleration profiles have been analyzed for driveability for two different velocity profiles that are followed in a stretch of 720 m between stop signs. The controller gains have been re-tuned based on the parameter space robust control PID approach for driveability and compared with the original gains. The US06 SFTP drive cycle has also been used for the comparison of the two different controller gain sets.

Propeller research has generally been focussed on improving the open water efficiency, and by considering the various energy losses associated with the marine screw propeller, it can be seen that for a design brief with given main engine power and RPM input, plus a thrust requirement defined by the specified ship speed, the most fruitful area for improvement in efficiency by propeller design is a reduction in energy losses. The simple way to increase the efficiency is reduction of blade area, increasing load near the tip and adopting a larger diameter with low RPM. However, vibration and noise will be the first issues when a designer tries to increase the efficiency of the propeller by these ways. This paper will present a simple prediction method of pressure fluctuations induced by thickness, propeller loading and unsteady cavitation taking not only propeller dimensions but also stern shape into account at the beginning of the propeller design.

Yapılan çalışmada depolama sistemlerinde kullanılan otomatik depolama vincinin titreşiminin kontrol edilmesi ve bu sayede ürün alma bırakma zamanının azaltılması için sisteme girilen sinyalin ileri besleme kontrolü ile uygulanması incelenmiştir. Kontrol edilmesi amaçlanan otomatik depolama vinci için yapının indirgenmiş bir modeli belirlenmiş ve buna uygun bir matematik model ortaya koyulmuştur. Kontrol edilecek sistem tek eksende çalışmakta ve bu ekseni tek bir motor kontrol etmektedir. Sistemin aldığı komuta göre takip edeceği trapezoid biçimdeki yörünge planlaması tasarlanan bir algoritma ile belirlenmiştir. Algoritmaya girilen konum, hız, ivme ve jerk değerleriyle ve algoritmadan jerk türevi çıktısı alınmıştır. Sisteme giren jerk türevi komutu, asenkron motora tork komutu olarak girilmiş ve diğer hatalar PID geri-beslemeli kontrol ile azaltılmıştır. Sistemin Simulink ortamında modeli hazırlanmış, örnek bir 10 metrelik komut ile sistem simülasyonu yapılmıştır. In this paper we study the feed-forward control of vibrations in the ASRS stacker crane, hence reducing the pick & place time of the payload that it is carrying. The stacker crane structure in our study has been simplified and an expedient mathematical model has been presented. In accordance with the reference command signal, a trapezoidal trajectory to follow is constructed by an algorithm. With the position, velocity, acceleration and jerk inputs to the algorithm, the derivative of the jerk is taken as an output. The jerk derivative command translates as a torque command to the asynchronous motor and errors are reduced by PID feed-back control. The model of the system is constructed in the Simulink environment, and the system was simulated with a sample 10-meter displacement command.

OBJECTIVE: We performed a scoping review of algorithms using electronic health record (EHR) data to identify patients with Alzheimer’s disease and related dementias (ADRD), to advance their use in research and clinical care. MATERIALS AND METHODS: Starting with a previous scoping review of EHR phenotypes, we performed a cumulative update (April 2020 through March 1, 2023) using Pubmed, PheKB, and expert review with exclusive focus on ADRD identification. We included algorithms using EHR data alone or in combination with non-EHR data and characterized whether they identified patients at high risk of or with a current diagnosis of ADRD. RESULTS: For our cumulative focused update, we reviewed 271 titles meeting our search criteria, 49 abstracts, and 26 full text papers. We identified 8 articles from the original systematic review, 8 from our new search, and 4 recommended by an expert. We identified 20 papers describing 19 unique EHR phenotypes for ADRD: 7 algorithms identifying patients with diagnosed dementia and 12 algorithms identifying patients at high risk of dementia that prioritize sensitivity over specificity. Reference standards range from only using other EHR data to in-person cognitive screening. CONCLUSION: A variety of EHR-based phenotypes are available for use in identifying populations with or at high-risk of developing ADRD. This review provides comparative detail to aid in choosing the best algorithm for research, clinical care, and population health projects based on the use case and available data. Future research may further improve the design and use of algorithms by considering EHR data provenance.

This paper investigates the control and safety of a series of maglev trains moving on multi-span simply supported bridges with the foundation settlements. To control the dynamic response of the maglev trains, a PI (proportional-integral) controller with constant tuning gains is applied. The finite element results indicate that the influences of the rail irregularities are obvious. However, the allowable vertical settlement and the Y-deflection of the bridge, which is caused by the X-rotation can be significantly improved when the lateral electromagnetic force is enlarged. Keywords-Maglev train; PI control, Rail irregularity; Finite element method; Foundation settlement; Newmark method

Previous studies have suggested that water-soluble polysaccharides from fermented carrot pulp (WSP-p) have stronger anti-diabetic effects than those from un-fermented carrot pulp (WSP-n). This study aimed to improve understanding of these functional differences by comparing their molecular structures. Weight-average molecular weights of WSP-p fractions were lower than those of the corresponding WSP-n fractions. While both WSPs had similar functional groups, more fragmented particles were observed on the surface of large particles of WSP-n than WSP-p. Monosaccharide composition and methylation analysis confirmed that both WSP-p and WSP-n were pectic polysaccharides, containing rhamnogalacturonan-I-type polysaccharides with 1,4-linked α-d-galacturonic acid residues and homogalacturonan regions with 1,4-GalpA linkages. 1H and 13C NMR showed that they had similar linkage patterns. These findings suggested that probiotic fermentation of WSP mainly cleaved the linkages between repeating units, and resulted in less polydisperse molecular size distributions.

Internet of Things technologies open up new applications for remote monitoring of forests, fields, etc. These networks require autonomous operation: combining ultra-long-range connectivity with low energy consumption. While typical low-power wide-area networks offer long-range characteristics, they fall short in providing coverage for environmental tracking in ultra-remote areas spanning hundreds of square kilometers. This paper presents a multi-hop protocol to extend the sensor's range, whilst still enabling low-power operation: maximizing sleep time by employing prolonged preamble sampling, and minimizing the transmit energy per actual payload bit through forwarded data aggregation. Real-life experiments, as well as large-scale simulations, prove the capabilities of the proposed multi-hop network protocol. By employing prolonged preamble sampling a node's lifespan can be increased to up to 4 years when transmitting packages every 6 h, a significant improvement compared to only 2 days when continuously listening for incoming packages. By aggregating forwarded data, a node is able to further reduce its energy consumption by up to 61%. The reliability of the network is proven: 90% of nodes achieve a packet delivery ratio of at least 70%. The employed hardware platform, network protocol stack and simulation framework for optimization are released in open access. ispartof: SENSORS vol:23 issue:11 ispartof: location:Switzerland status: published

Probing the stress state using a high density of measurement points is time intensive and presents a limitation for what is experimentally feasible. Alternatively, individual strain fields used for determining stresses can be reconstructed from a subset of points using a Gaussian process regression (GPR). Results presented in this paper evidence that determining stresses from reconstructed strain fields is a viable approach for reducing the number of measurements needed to fully sample a component’s stress state. The approach was demonstrated by reconstructing the stress fields in wire-arc additively manufactured walls fabricated using either a mild steel or low-temperature transition feedstock. Effects of errors in individual GP reconstructed strain maps and how these errors propagate to the final stress maps were assessed. Implications of the initial sampling approach and how localized strains affect convergence are explored to give guidance on how best to implement a dynamic sampling experiment.

The challenging idea of using drones in last-mile delivery systems of logistics addresses a new routing problem referred to as the traveling salesman problem with drone (TSP-D). TSP-D aims to construct a route to deliver parcels to a set of customers by either a truck or a drone, thereby minimizing operational costs. Since TSP-D is considered NP-hard, using metaheuristics is one of the most promising solutions. This paper presents a hybrid metaheuristic solution method of TSP-D based on two state-of-the-art algorithms: the genetic algorithm and ant colony optimization algorithm. Heuristics in TSP-D literature are based on two consequent decisions: truck routing and drone assignment. Unlike those in the existing literature, the proposed metaheuristic constructs both truck and drone routes simultaneously. Additionally, to the best of our knowledge, we introduce for the first time a solution method on the basis of an ant colony optimization approach to TSP-D. Additionally, we propose a binary pheromone framework for both drone and truck, diverging from the traditional pheromone structure. Computational experiments indicate that the proposed hybrid metaheuristic algorithm is able to generate optimal routes for provided instances of TSP-D benchmarking. In addition, the algorithm improves the best-known solutions of some instances found by rival heuristics.

In this paper, we investigated the applicability of ChatGPT AI in electronics research and development via a case study of applied sensors in embedded electronic systems, a topic that is rarely mentioned in the recent literature, thus providing new insight for professionals and academics. The initial electronics-development tasks of a smart home project were prompted to the ChatGPT system to find out its capabilities and limitations. We wanted to obtain detailed information on the central processing controller units and the actual sensors usable for the specific project, their specifications and recommendations on the hardware and software design flow additionally. Furthermore, an extensive literature survey was requested to see if the bot could offer scientific papers covering the given topic. It was found that the ChatGPT responded with proper recommendations on controllers. However, the suggested sensor units, the hardware and software design were only partially acceptable, with occasional errors in specifications and generated code. The results of the literature survey showed that non-acceptable, fabricated citations (fake authors list, title, journal details and DOI—Digital Object identifier) were presented by the bot. The paper provides a detailed qualitative analysis, a performance analysis and critical discussion of the aforementioned aspects while providing the query set, the generated answers and codes as supplied data with the goal to give added value to electronics researchers and developers if trying to reach out for the tools in their profession.

In this paper, the development and modeling of an electric Vertical-Take-Off-and Landing (eVTOL) aircraft with tiltable rotors. The front two rotors have tilting capability for transition flight from vertical take-off to forward-direction level flight. This paper focuses on the design and analysis of an eVTOL aircraft platform. The study includes layout and system architecture, the selections and optimization of components, such as electric motors, batteries, and controllers, as well as the integration of these components into the overall aircraft system. In addition, the dynamical model is derived as a nonlinear differential equation. Afterwards, a linearization-based model and Linear Parameter-Varying (LPV) model embedding from nonlinear model are presented. The study provides insights into the system-level design and analysis of VTOL aircraft. Future work includes the trajectory planning and control system design, as well as the simulation/experimental validations using the eVTOL aircraft platform.

Centrifugal flow impellers are commonly used in a wide variety of industrial machines. Predicting the performance of these impellers over the entire operating range is key to the system development during the early design stages. The two element in series (TEIS) and two-zone model can be used to accurately predict impeller performance based on flow physics and empirical correlations. Correlations were made with linear regression on a database of 50 pumps and 75 impellers. These correlations were later found to only apply to designs that are similar to those in the database. This paper proposes a new method to generate correlations for the TEIS and two-zone model using reduced order modeling and machine learning. The models will be trained using the same database used in developing the previous correlations, but will also include additional data and computational fluid dynamics (CFD) results. The models will be used to improve the known correlations and to discover new correlations between the machine performance and design variables.

Origami principles, patterns, and thickness accommodation techniques have been explored and tested for engineering applications in many fields. Two of the main difficulties of transferring a design from folded paper to thicker, stiffer materials are accommodating thickness and replicating folding motion with surrogate folds. While literature reviews exist for thickness accommodation, it is difficult for a designer to survey and assess work that has been on the subject of surrogate folds. Currently, many engineering origami instances limit themselves to using pin hinges, adjusting all other design parameters to accommodate pure revolute motion. The possibilities for origami design and application are augmented when designers are aware of the array of capabilities compliant surrogate folds have to offer. This work categorizes compliant mechanisms that may be effective as surrogate folds in a large array of origami applications. This catalog is a tool for designers of origami systems to select and/or design mechanisms that can imitate folds. Principles and characteristics are discussed that a designer should consider in order to design dynamic origami systems that more effectively meet design requirements. These characteristics include manufacturing considerations; controlling and utilizing off-axis motion; and introducing secondary functions surrogate folds may play beyond attaching panels together, such as damping, self-deploying, self-stabilizing, and/or conducting heat or electricity. Also presented are guidelines on how to use this catalog to design new or adapt existing surrogate fold mechanisms by parameterizing aspects of material, geometry, and topology. The organization structure is explained, and future work introduced on how this tool will be further refined.

Brown dwarfs are substellar objects that form like stars but never achieve the core temperatures and pressures needed to ignite hydrogen fusion. These "failed stars" have been shown to exhibit complex atmospheres similar to those of planets, making them useful analogs for exoplanets. As a brown dwarf cools over time, different cloud species condense or fall below the surface of the atmosphere, causing changes in the resulting spectrum of the object. Comparison of theoretical atmospheric models to real brown dwarf spectra can provide insight into the physical and chemical processes occurring in the atmosphere of the object. We have fit over 300 archival and new brown dwarf spectra with atmospheric models in order to discover where the models are fitting the data well and where current modeling techniques might need improvement. In this paper, we present some of the general trends we have observed, why this work is important to the astronomical community, and the next steps for this project.

This paper describes two interrelated library building projects at Technological University Dublin. The first is the ongoing construction of an Academic Hub to accommodate the library and other academic support services, incorporating a protected structure into a new building. The second is the refurbishment of part of an office block, originally built in 1970 to be a hotel, to house an interim library until completion of the Academic Hub. This project has provided valuable information for the Academic Hub project.

Additive manufacturing (AM) of metals is stimulating the tool making industry. Moreover, besides the production of lost forms, AM processes are now being used to directly generate tools, molds or parts, leading to massive time savings. In the case of material development for AM, the challenge is to operate with carbon-containing iron-based materials distinguished by high strength and hardness, as well as high corrosion resistance and thermal conductivity. Often, those materials are susceptible to crack formation during processing. Using Electron Beam Powder Bed Fusion (PBF-EB), the challenge of crack formation can be overcome by using high process temperatures in the range 800–900 °C. In this paper, results on the processing of a cold-working tool steel (X65MoCrWV3-2) and a hot-working steel (X37CrMoV5-1) will be presented. These include the processing window, processing strategies to minimize the density of cracks and properties with respect to microstructure and hardness.

Neutral buoyancy systems simulate the microgravity environment by taking advantage of buoyancy forces of water to offset the gravity of test bodies. Functional verification of space robots in neutral buoyancy system is of great importance for ground tests. The relative pose determination of a spacecraft plays an essential role in the on-orbit operation of space robots. In order to meet the requirement of on-orbit operation ground verification for space robots, this paper develops a vision-based system for determining the relative pose of cooperative spacecraft in neutral buoyancy environment. Cooperative markers and underwater binocular vision system are designed for the pose determination, and a cooperative spacecraft model is built. A detection and recognition method based on the topological characteristic is proposed for the cooperative marker. An underwater imaging model of binocular camera is established, and its refraction parameters are calibrated. The marker points are measured with an underwater binocular 3D measurement algorithm. Furthermore, the pose of cooperative spacecraft is determined using axisymmetric plane feature points. Additionally, the stable and reliable pose and velocity are obtained after the data are further processed with a Kalman filter. Finally, the experiments are carried out and the experimental results show that the proposed system can achieve a stable and reliable high-precision relative pose determination for cooperative spacecraft in neutral buoyancy environment.

Purpose: Property education is predominantly taught at undergraduate level, supported by post-graduate programs at many Australian universities. This paper examines undergraduate property programs from the perspective of one of the major stakeholders; the property industry. The current offerings have evolved from highly applied practical valuation-centric programs in the 1970s to broader, more academic programs in the current era. This change has created different expectations for both students and industry._ _Methodology: Initially a focus group of six property industry employers was held and their discussion is included in the paper and informed the development of a questionnaire using the online delivery vehicle Qualtrics. This questionnaire was emailed to 460 industry leaders, as listed on company websites and university Employer of Choice databases. 95 people responded to the questionnaire.Findings: After surveying students, recent graduates and industry leaders, it appears as if there is a gap between what the universities claim about their graduates and what many employers of property graduates find. Despite the best efforts of the universities and their staff, despite robust and rich curricula, it would appear that evidence from industry and the Australian Property Institute who register practitioners, is that most graduates require specialist training and additional study before they can be considered work ready.Value: This paper offers valuable insights with regard to how higher education property programs are regarded by the property industry in Australia.

The whole world is focusing on the utilization of renewable energy sources in order to mitigate the world power crisis. Power electronics is being used in a large scale for the renewable energy conversion in a more efficient manner. It has a great impact on controlling as well as interfacing the renewable system with both the grid and standalone applications. Hence more and more emphasis is given on design and control of power converters. In this paper different renewable energy systems (wind, solar) with different aspects of their power conversion have been discussed. Some basic principles of their operations with their recent technology advancements are reviewed. It is the reality that power electronics plays a vital part on interfacing and hence increasing the overall performance.

Earthquake-induced pounding between structures has been widely studied by using different impact models. In this paper, we first briefly introduced the existing impact analysis models and discussed their shortcomings. For the Hertz-damp impact analysis model, the damping constants do not accord with the physical facts; then, based on the Hertz theory, the expression of the damping constant in the Hertz-damp impact analysis model is improved. The approximate formula of the damping constant is theoretically derived, and the accuracy and effectiveness of the calculation formula of the damping constant are verified by the selected collision analysis problems.

Ontologies enable both humans and machines to communicate precisely to support the exchange of semantics by defining shared collective domain knowledge. In this paper we build an ontology using Protege to organize knowledge of Indian Government portal. IndiGov-O, the ontology of Indian Government is a 4-level hierarchy in which various ministries of India, their respective departments and further functions and schemes have been conceptualized. The idea is to envision "digital governance" by virtue of social web adoption to a government model based on knowledge.

The shift to a circular economy and the use of wind energy are key components in achieving the climate goals that some governments like Germany have set for themselves. Nevertheless, the wind energy industry is still predominantly organized as a linear system. Therefore, this paper outlines the existing research on the wind energy supply chain and embeds it in the context of a circular economy. The results show that some aspects of the circular economy have recently gained attention. For instance, the recycling of wind turbine blades is often discussed in literature. However, circular thinking is still underrepresented in supply chain management research. For example, studies on return, recover and deliver processes are rare. By presenting a structured overview of the current state of research, an agenda for future investigations can be derived. Hence, this publication makes a clear contribution towards becoming more circular in the wind energy supply chain.

Tire shreds have gained wide acceptance as an engineered fill in the last two decades. Ladder-type metal reinforcement can be used to reinforce MSE walls with tire shred-sand mixtures as a backfill material. This paper reports the results of laboratory pullout testing performed on ladder-type metal reinforcement embedded in tire shred-sand mixtures. The ladder-type metal reinforcement consists of two parallel longitudinal steel bars welded to a series of cross bars forming rectangular apertures. Mixtures of Ottawa sand with 50–100 mm size tire shreds were prepared at different mixing ratios (0%, 20%, 25%, and 35% by weight of tire shreds). Pullout tests were performed under three normal stresses – 40 kPa, 65 kPa, and 90 kPa. The test results show that the ladder-type metal reinforcement provides higher pullout resistance in tire shred-sand mixtures than in sand alone. Compared to metal-strip reinforcement, ladder-type metal reinforcement provides higher pullout capacity due to the passive resistance that results from the interlocking of tire shreds within the grids of the ladder-type reinforcement. The pullout resistance increased with increasing tire shred content up to 35% (by weight of tire shreds), beyond which segregation of the mixtures was observed.

The coronavirus (COVID-19) pandemic forced a rapid transition of K-16 education to remote and online learning in the final quarter of the 2019–2020 school year. The disruption was extreme for all teachers in K-12 but particularly for teachers involved in pilot programs, such as the NSF-funded Engineering for Us All (e4usa) project. This paper reports the key findings obtained through systematic data collection from a pilot cohort of high school teachers who adapted a brand-new engineering curriculum during the COVID-19 pandemic, students who experienced the adapted curriculum, and a new cohort of teachers who were tasked with teaching the updated curriculum.

To address the data review burden and improve the reliability of the ultrasonic inspection of large composite structures, automated data analysis (ADA) algorithms have been developed to make calls on indications that satisfy the detection criteria and minimize false calls. The original design followed standard procedures for analyzing signals for time-of-flight indications and backwall amplitude dropout. However, certain complex panels with varying shape, ply drops and the presence of bonds can complicate this interpretation process. In this paper, enhancements to the automated data analysis algorithms are introduced to address these challenges. To estimate the thickness of the part and presence of bonds without prior information, an algorithm tracks potential backwall or bond-line signals, and evaluates a combination of spatial, amplitude, and time-of-flight metrics to identify bonded sections. Once part boundaries, thickness transitions and bonded regions are identified, feature extraction algorithms are applied to multiple sets of through-thickness and backwall C-scan images, for evaluation of both first layer through thickness and layers under bonds. ADA processing results are presented for a variety of complex test specimens with inserted materials and other test discontinuities. Lastly, enhancements to the ADA software interface are presented, which improve the software usability for final data review by the inspectors and support the certification process.

In this paper, defect detection and identification in aluminium joints is investigated based on guided wave monitoring. Guided wave testing is first performed on the selected damage feature from experiments, namely, the scattering coefficient, to prove the feasibility of damage identification. A Bayesian framework based on the selected damage feature for damage identification of three- dimensional joints of arbitrary shape and finite size is then presented. This framework accounts for both modelling and experimental uncertainties. A hybrid wave and finite element approach (WFE) is adopted to predict the scattering coefficients numerically corresponding to different size defects in joints. Moreover, the proposed approach leverages a kriging surrogate model in combination with WFE to formulate a prediction equation that links scattering coefficients to defect size. This equation replaces WFE as the forward model in probabilistic inference, resulting in a significant enhancement in computational efficiency. Finally, numerical and experimental case studies are used to validate the damage identification scheme. An investigation into how the location of sensors can impact the identified results is provided as well., European Union’s Horizon 2020 Marie Skłodowska-Curie 859957, Science and Technology Development Fund, Macau SAR (File No.: FDCT/0101/2021/A2, FDCT/001/2021/AGJ and SKL-IOTSC(UM)-2021-2023)

In this paper, we propose a method to analyze the amount of operation reserves procured in a system based on two stages. The first stage is a detailed hourly unit commitment and the second stage is a simulation model with a shorter time period. The method is applied to the Spanish hydrothermal system and several cases are analyzed to determine the impact of the time period in the use of the operation reserves.

A domestic water heating system that combines photovoltaic thermal (PVT) solar collectors with two heat pumps, in a novel cascade arrangement, is presented and analyzed in this paper. The goal of this analysis is to determine and compare the annual thermal energy output of the PVT cascade heat pump system with an evacuated tube and simultaneous consumption PVT single heat pump water heating system. The computational technique that was developed to analyze the PVT cascade heat pump system, which determines solar panel energy outputs, and heat pump operating characteristics, is described in detail. Case study simulation results are also presented, which include transient power output profiles, temperature profiles, and yearly energy output results. Hourly weather data, including air dry-bulb temperatures and solar flux values, from locations with a range of climates was used in these simulations. The results of this study show that the PVT cascade heat pump system has an annual thermal energy output improvement over the evacuated tube heating system ranging from 37% to 68%, depending on the selected simulation location.