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In the era of Industry 4.0 and the introduction of new technologies, collaborative workplaces represent the potential to increase the efficiency of manufacturing systems. The presented research focuses on studying the impact of changing the speed and acceleration of a Cobot to the number of finished products at a collaborative workstation, the average assembly time, and the utilization of the Cobot and worker. In a laboratory experiment, it was demonstrated that changing the parameters of the Cobot significantly affects the optimization parameters of the collaborative workstation productivity. The results indicate an increase in production capacity with an increase in the speed and acceleration of the Cobot, while at the same time highlighting the importance of uniform utilization and occupancy of the Cobot and worker. The findings are particularly interesting from the influence of the Cobot’s audio and video effects on worker, when reducing the average assembly time while increasing the Cobot's capabilities. The results and findings presented open up important new areas of research in the field of social, time and financial justification of collaborative workplaces.

Waste heat recovery in the energy intensive industry is one of the most important measures for the mitigation of climate change. The utilization of just a fraction of the theoretically available waste heat potential would lead to a significant reduction of the primary energy consumption and hence a reduction of greenhouse gas emissions. The present study examines the integration of a packed bed thermal energy storage for waste heat recovery in the iron and steel industry. Along with the highly fluctuating availability of excess heat the main difficulty of waste heat recovery in industrial processes is the high amount of powder that is transported by the hot exhaust gases. Therefore, investigations focus on the pressure drop and powder hold-up in a packed bed thermal energy storage that is operated with a gas-powder two phase exhaust gas as heat transfer fluid with the ultimate goal to assess its suitability and robustness under such challenging operational conditions. The results indicate, that 98 % of the powder that is introduced into the system with the heat transfer fluid during charging accumulates in the packed bed. Remarkably, most of the powder hold-up in the packed bed is concentrated near the surface at which the heat transfer fluid enters the packed bed. When reversing the flow direction of the heat transfer fluid to discharge the storage with a clean single phase gas, this gas is not contaminated with the powder that has been accumulated in previous charging periods. Further, the radial distribution of the powder hold-up in the packed bed is observed to be even which indicates that there is no risk of random flow channel formation that could affect the thermal performance (storage capacity, thermal power rate) of the system. The results reinforce the great potential of packed bed thermal energy storage systems for waste heat recovery in the energy intensive industry., Comment: submitted to Applied Energy

In recent years, there have been more and more collaborative workplaces in different types of manufacturing systems. Although the introduction of collaborative workplaces can be cost-effective, there is still much uncertainty about how such workplaces affect the capacity of the rest of production system. The article presents the importance of introducing collaborative workplaces in manual assembly operations where the production capacities are already limited. With the simulation modelling method, the evaluation of the introduction impact of collaborative workplaces on manual assembly operations that represent bottlenecks in the production process is presented. The research presents two approaches to workplace performance evaluation, both simulation modelling and a real-world collaborative workplace example, as a basis of a detailed time study. The main findings are comparisons of simulation modelling results and a study of a real-world collaborative workplace, with graphically and numerically presented parameters describing the utilization of production capacities, their efficiency and financial justification. The research confirms the expediency of the collaborative workplaces use and emphasise the importance of further research in the field of their technological and sociological impacts.

This paper presents a high-speed high-resolution low-finesse Fabry–Perot sensor interrogation system. The system utilizes a standard telecommunication distributed-feedback laser diode and an all-digital high-speed signal processing based on field-programmable-gate-array. The system can resolve multiple Fabry–Perot Interferometers (FPI) simultaneously, which might include multiple sensors, multiparameter sensors, or combinations of sensor(s) and reference FPIs. This opens up possibilities for adopting different measurement system configurations and compensation schemes. The system exhibits white-noise characteristics for a system bandwidth above 100 Hz, with spectral density of about 2 pm/√Hz when interrogating about 1 mm long low-finesse FPI. At an output sampling rate of 10 Hz, a sensor measurement length resolution of less than 50 pm was demonstrated for about a 600 μm long sensing cavity (corresponding to a strain resolution of about 70 nϵ). Proper use of simple all-fiber reference also provided low long-term drift. The system provides an up to 40 KHz sampling rate and was used to demonstrate dynamic measurement of strain variation on a piezo-electric stack and for interrogation of in-cylinder pressure variations within a high-rotation-rate miniature diesel engine. Fabry–Perot sensors with typical lengths between a few hundred and a few mm can be read-out with the current version of the proposed interrogator. The proposed system was built out of a small number of highly cost-efficient optoelectronics and electronics components (all used in FTTH) and thus, opens-up potential for new applications where the cost of interrogation is presently limiting.

Left Atrial Appendage Closure With the New Occlutech® DeviceAims Percutaneous left atrial appendage closure (LAAC) is a valuable treatment option for stroke prevention in patients with atrial fibrillation and a HAS-BLED-Score ≥3. Determinants of procedural safety events and neurological outcome of the patients with the Occlutech device (OD) are not established yet. Methods and Results Between 2012 and 2016, 30 patients underwent LAAC using the OD. This is a prospective study. Neurological examination and transesophageal echocardiography was performed directly before and after the procedure and after 1, 3, and 12 months. The OC was successfully implanted in 28 of the 30 enrolled patients (93%). Two patients presented a hemodynamic relevant pericardial effusion. A leak

Ena glavnih komponent stiskalnice je hidravličen valj. V našem primeru stiskalnica stoji v nizkem prostoru, kjer glede na željen delovni hod ni mogoče zasnovati normalnega hidravličnega valja. Glede na dovoljeno višino delovni hod valja ter ostale pogoje smo zasnovali dvosmeren teleskopski hidravličen valj. Diplomska naloga vsebuje pregled literature o že obstoječih rešitvah, zasnovo dvosmernega teleskopskega hidravličnega valja, teoretične preračune, opis delovanja hidravličnega sistema ter vso potrebno dokumentacijo za izdelavo valja. Valj je zasnovan tako, da izpolnjuje naročnikove želje ter omogoča normalno delovanje stiskalnice. One of the main components of the press is a hydraulic cylinder. In our case the press is standing in a low space where, according to the desired working stroke, it is not possible to design a normal hydraulic cylinder. Depending on the permissible height, the working stroke of the cylinder and other conditions, a two-way telescopic hydraulic cylinder will be designed. The thesis contains a review of the literature on existing solutions, the design of a double acting telescopic hydraulic cylinder, theoretical calculations, a description of the operation of the hydraulic system, and all necessary documentation for the manufacture of a cylinder. The cylinder is designed to satisfy the customer’s wishes and enable the normal operation of the press.

Sistemi za spektralno razločevanje optičnovlakenskih senzorjev so dandanes kljub hitremu razvoju optičnih senzorjev še vedno dokaj kompleksni in posledično dragi, kar preprečuje uvajanje optičnih vlakenskih senzorjev v širši spekter industrijskih in drugih aplikacij. V okviru doktorske disertacije smo raziskali in izdelali merilni sistem, s katerim lahko spektralno razločujemo optičnovlakenske senzorje, ki temeljijo na Fabry-Perotovem interferometru. Merilni sistem, ki je predmet doktorske disertacije, je bil izdelan izključno iz majhnega števila cenenih telekomunikacijskih elektro-optičnih komponent. Za nastavljiv laserski vir smo tako uporabili lasersko diodo DFB, ki smo jo vzbujali s tokovnimi sunki višjih amplitud. Pravilna oblika tokovnega sunka skozi lasersko diodo DFB, selektivno in časovno linearno segreje aktivno področje, kar povzroči linearen zamik valovne dolžine izsevanega optičnega spektra za okoli 11 nm. Pri tokovnem vzbujanju laserske diode DFB se tako generira valovno-dolžinsko zamaknjen optični sunek, s katerim razločimo dolžino Fabry-Perotovega interferometra tako, da opazujemo odbito svetlobno valovanje t.i. interferenčni vzorec, ki ima značilno kosinusno obliko. Z uporabo tehnike merjenja faze v kosinusni spektralni karakteristiki Fabry-Perotovega interferometra lahko razločimo informacijo o merjeni veličini. S predlaganim merilnim sistemom lahko zaznavamo spremembo optične poti preko zaznavanja spremembe faze v spektru Fabry-Perotovega interferometra s frekvenco vzorčenja 40 kHz in ločljivostjo zaznavanja optične poti 2,7 nm. Če uporabimo digitalno filtriranje zajetih merilnih vrednosti, pri čemer zmanjšamo pasovno širino merilnega sistema na 1 Hz, lahko zaznavamo spremembe optične poti v Fabry-Perotovem interferometru z ločljivostjo 46 pm (npr. polmer atoma vodika znaša rB = 53 pm). Zaradi naslavljanja Fabry-Perotovih senzorjev s kratkimi optičnimi sunki lahko spektralno razločujemo tudi več Fabry-Perotovih optičnih senzorjev z različnimi ali enakimi nazivnimi dolžinami. Predstavljen merilni sistem za spektralno razločevanje Fabry-Perotovih senzorjev omogoča zasnovo stroškovno ugodnega senzorskega sistema, s katerim lahko z visoko ločljivostjo izvajamo statično ali dinamično meritev poljubne fizikalne veličine. V okviru disertacije so z uporabo predlaganega sistema za razločevanje Fabry-Perotovih interferometrov prikazane visoko-ločljive meritve raztezkov, tlakov, temperature, lomnega količnika in jakosti električnega polja. V ta namen smo uskladili nekatere obstoječe senzorje s predlaganim sistemom za razločevanje oz. uporabili nove rešitve za zaznavanje električne poljske jakosti. Efficient signal interrogation of fiber-based sensors still presents a major challenge that limits the introduction of these sensors into a broad span of practical applications. This is an even more pronounced problem when there is a need for measurements requiring a high-speed signal interrogation. Research conducted in our dissertation lead to fabrication of a novel interrogation system for fiber optic sensors employing Fabry-Perot interferometry (FPI). The proposed system was built out of a small number of highly cost-efficient optoelectronics and electronics components and has the potential to yield in applications, where the cost of interrogation is presently limiting, while preserving the resolution and stability of conventional spectral resolved methods. The proposed system was built around a standard Telecom distributed-feedback (DFB) laser diode, which was driven by short and high-amplitude current pulses. When a small active region diode is driven by a short and high-amplitude current pulse, rapid and selective heating occurs of the diode’s region and its immediate vicinity. Since the diode’s distributed feedback structure resides in the vicinity of the diode’s active region, this leads to a rapid and significant wavelength shift for about 11 nm of emitted optical spectrum. Produced high-power and extensive frequency-swept optical pulses were then guided to one or more all-fiber FPIs, which back-reflected part of the incoming frequency swept light. Back-reflected optical pulses were modulated over time due to the FPIs’ distinctive and periodic spectral characteristics. Real-time signal processing through multiplication of the incoming data vector with sine and cosine matrices were then utilized to extract phases of the spectral fringes of the interrogated one or multiple FPIs. The achieved FPI optical path length measurement resolution was in the range of 2.7 nm at a 40 KHz sampling rate. When the low pass filter was applied to reduce the system bandwidth to 1 Hz the resolution corresponded to about 46 pm. For comparison, the radius of the hydrogen atom (H) is 53 pm. Proposed solution presents a cost efficient, high resolution interrogation system for dynamic and static measurements, that can resolve multiple Fabry-Perot Interferometers simultaneously, which might include multiple sensors, multi-parameter sensors, or combinations of sensor(s) and reference FPIs. High-resolution interrogation was demonstrated employing fiber optic Fabry-Perot sensors for measuring a variety of physical parameters, such as strain, pressure, temperature, refractive index and electric field intensity for which a novel sensor was presented.

Spremembe koncepta otroka, otroštva in otroškega bralca so v osemnajstem stoletju prinesle drastičen premik v razumevanju literature, saj je prišlo do delitve bralcev glede na njihovo starost in posledično do rojstva mladinske literature. Pred tem so si otroci in odrasli delili iste knjige. Pojav in uspeh serij o Harryju Potterju je v devetdesetih letih ponovno odprl vprašanja o starostnih mejah bralcev, ki je rezultiral v pojav izraza "crossover" literatura. Izraz opisuje naslovniško odprto literaturo, ki je namenjena otrokom in odraslim. "Crossover" literatura preči tudi meje tradicionalnega dojemanja literarnih žanrov, zvrsti in oblik. Nekateri trdijo, da naslovniška odprtost povzroča infantilizacijo družbe, izginjanje otroštva ter mladinske literature ter menijo, da je ta proces simptom postmodernizma. Teoretiki kot sta Sandra Beckett in Rachel Falconer te ideje zavračata in opominjata, da so meje med knjigami za odrasle in knjigami za otroke umetno tvorjene in da je skupna literarna dediščina vedno obstajala. "Crossover" fenomen se kaže tudi v slikaniški produkciji, ki je tradicionalno gledano primarno namenjena predbralnim otrokom in je že zaradi konstantne interakcije med otrokom in odraslim v procesu branja "crossover" format. Hkrati pa zaradi svoje narave, ki teži k povezovanju med literaturo in vizualnimi umetnostmi, ponuja veliko svobodo in možnosti za eksperimentiranje. Izbrane slovenske in češke slikanice, ki bi jih lahko brali skozi "crossover" perspektivo, kažejo na težave pri klasifikaciji in iskanju skupnih značilnosti. Skupno jim je prestopanje tematskih ter idejnih zakonitosti slikanice ali pa prestopanje meja znotraj same zvrsti, skozi likovno podobo ali celo z odtegnitvijo besedila, ki spodbuja kreativen pristop k branju ter omogoča naslovniško odprtost.Changes in the concept of child, childhood and child reader in the 18th century brought a drastic shift in literature, leading to the division of readers based on their age and consequently to the birth of children's literature. Before that children and adults shared the same books. With the success of Harry Potter series in the 1990s, questions arose regarding age boundaries and that led to the idea of crossover literature. The expression describes literature written for a dual audience that can be both children and adults. Crossover literature also crosses the boundaries of traditional ideas of literary genre and form. Some say this is a symptom of postmodernism and that these changes cause infantilisation of adult world, disappearance of childhood and children's literature. Scholars like Sandra Beckett and Rachel Falconer deny these theories and say that the borders between books for children and books for adults were artificially formed and that books for children and books for adults have always had a common literary history. Crossover phenomenon is also present in the literary production of picture books that have traditionally been intended for pre-readers. Since picture books require constant interaction between a child and an adult in the reading process, a picture book is already a crossover form in its primary idea. At the same time the relation between the text and the visual images in picture books presents a lot of possibilities for new and innovative approaches. Selected Slovene and Czech picture books that allow for reading from the crossover perspective show how difficult it is to create a solid system of classification and find common characteristics in works that are part of the crossover phenomenon. What they all share is crossing traditional borders in themes and ideas that they are trying to portray. These picture books also cross genre boundaries through the visual aspects of the books or even through complete disappearance of text, which encourages a creative approach to reading and opens the age boundaries of the addressee.

This paper presents a miniature Fabry-Perot voltage sensor created at the tip of an optical fiber. The sensor utilizes a micro-machined, all-silica, opto-mechanical structure that is flexed under the presence of attractive forces generated among charged bodies. The small dimensions and short response times of the structure provide an opportunity for measurement of the DC and AC voltages within the range of power grid frequencies. The experimental sensor length was less than 5 mm, and the sensor's sensitivity is sufficient for measurements of voltages in mid-voltage, and even low voltage, ranges. The sensor has a parabolic response to the applied voltage and can be adapted to a variety of voltage ranges by selecting the proper geometrical configuration. We demonstrate experimentally sensors with measurement ranges between 100 V and 1 KV (higher voltage ranges are also straightforwardly attainable) and with resolutions as low as 0.1 V.

Percutaneous left atrial appendage closure (LAAC) is a valuable treatment option for stroke prevention in patients with atrial fibrillation and a HAS-BLED-Score ≥3. Determinants of procedural safety events and neurological outcome of the patients with the Occlutech device (OD) are not established yet.Between 2012 and 2016, 30 patients underwent LAAC using the OD. This is a prospective study. Neurological examination and transesophageal echocardiography was performed directly before and after the procedure and after 1, 3, and 12 months. The OC was successfully implanted in 28 of the 30 enrolled patients (93%). Two patients presented a hemodynamic relevant pericardial effusion. A leak3 mm could be documented direct after implantation in 4 patients. After 3 months, there were only 2/4 patients with persistent LAA leakage with a maximum leakage of3 mm. The correct position of the device was confirmed in 27/28 patients during 3-month follow-up. In 2 patients, there was a thrombus at the OC. In 12 patients, a transoesophageal echocardiography was performed after 12 months. All patients (12/12) showed a correct placement of the device. None of the patients developed a clinically apparent stroke or died during follow-up.In this uncontrolled, nonrandomized study, acute and 3-month follow-up success of LAAC using OD was high. No patient showed significant neurological deficits.

The purpose of this study is to investigate the effects of word of mouth on consumers’ attitudes toward the product and its purchase probability. Furthermore, we examine the moderating influence of susceptibility to interpersonal influence, which is a personal characteristic of the receiver of word of mouth information. A quasi experiment was conducted, in which subjects were asked to evaluate a product, while being subjected to positive or negative word of mouth. Our results indicate that negative word of mouth has an impact on consumers’ attitudes and purchase probability, while the influence of positive word of mouth was not significant. Interestingly, susceptibility to interpersonal influence does not play a moderating role. While the experimental design with an unknown word of mouth source and fictitious brand allowed the comparison of results for the positive, negative, and control group, such conditions do not correspond to an actual market setting.

The integration of renewable energy sources in medium and low voltage grids is a not to be underestimated challenge for operators and planners both of the plants as well as of the grid operators. Questions concerning the compliance with the acceptable voltage limits, transmission capacity, active and reactive power balance, grid stability, economic efficiency and environmental benefits have to be answered. In addition, the use of additional equipment suggests that the reliability of the system could decrease. In this paper, on the one hand, an effective method to forecast voltage fluctuations caused by decentralized generation units in suburban distribution grids is presented based on a quick graphic determination method and is compared to exact load flow simulation results. On the other hand the load flow model is used to calculate the influence of the integration of the decentralized power generation units and grid restructuring measures on the system reliability. By way of an exemplarily medium and low voltage grid, these questions are answered.

Prvi zapisi o najemanju tujcev, ki so nudili svoje usluge v boju, segajo v čas več kot 2000 let pred našim štetjem. Od takrat naprej so se najemniški vojaki pojavljali v vseh zgodovinskih obdobjih, sprva kot posamezniki – plačanci, kasneje pa so se pričeli združevati in nastala so prva zasebna vojaška podjetja. Danes so zasebna vojaška podjetja pomemben akter pri zagotavljanju svetovne varnosti, njihovih storitev se poslužuje vedno več držav in različnih nevladnih organizacij, predvsem za podporne in varnostne naloge. Dejstvo je, da države ali organizacije niso same zmožne zagotavljati varnosti ali pa potrebujejo pomoč, da se same lahko posvetijo drugim dejavnostim, kot so npr. bojne naloge. Na ta varnostni pojav države zakonodajno niso bile pripravljene, zato so sprva podjetja delovala v nekakšni pravni praznini. To je bil tudi razlog, da je s strani teh podjetij oz. osebja prihajalo do velikega števila incidentov in do kršitev človekovih pravic in mednarodnega humanitarnega prava, za kar pa ni nihče odgovarjal. V odgovor so države, na podlagi trenutnih varnostnih vprašanj, pričele sprejemati ustrezne zakone za ureditev in nadzor nad varnostno industrijo. V pomoč jim je bil tudi Dokument iz Montreuxa. Čeprav ni pravno zavezujoč, daje državam smernice in usmeritve, da na tem področju sprejmejo ustrezne ukrepe na nacionalni ravni ter tako izpolnijo svoje obveznosti po mednarodnem pravu. Nasprotno pa v mednarodnem okolju še vedno obstaja pravna praznina na področju ureditve in nadzora zasebnih vojaških podjetij. To področje skuša urediti Delovna skupina o uporabi plačancev OZN z novo konvencijo, saj dosedanja dva mednarodna pravna akta nista zadostna za zasebna vojaška podjetja. The first records of contracting foreigners who offer their services in the battles, go back more than 2000 years BC. From then on, private actors occurred in all historical periods, first as individuals - mercenaries, but later they began to unite and the first private military companies were formed. Today, the private military companies are a major actor in global security, their services are used by an increasing number of countries and various non-governmental organizations, in particular for the support and security tasks. The reason for this lies in the fact that the countries or organizations are not able itself to provide security or they need help to get themselves more attention to other activities, such as combat missions. For this security phenomenon, states were not ready with their legislation, so the companies initially operated in some kind of a legal vacuum. This was also the reason that by these companies and their staff came to a large number of incidents and violations of human rights and international humanitarian law, for which usually no one answered. In response the countries, on the basis of a current security concerns, began to adopt the relevant laws for the regulation and oversight of security industry. To help them there was also Montreux document. Although it is not a legally binding, the document gives states guidelines and directions, that they can take appropriate measures at the national level in order to comply with their obligations under international law relating to private military companies. On the contrary, in the international environment there is still a legal vacuum in the area of regulation and oversight of private military companies. This area seeks to regulate the UN The Working Group on the use of mercenaries with the new convention, since so far two international legal instruments are not sufficient for a private military companies.

Magistrsko delo opisuje sistem, ki je grajen za namene razločevanja merilnih vrednosti pri vlakenskem Fabry-Perotovem interferometru. V delu je podrobno opisano teoretično ozadje delovanje senzorja, simulacija uporabljene modulacijske metode ter po sklopih opredeljena zasnova optičnega in elektronskega sistema. Na koncu so predstavljeni rezultati, kateri so plod predhodno zastavljenega dela. Master work describes system which is built for separation of measurement values in the fiber Fabry-Perot interferometer. In the work is described theoretical background of operation sensor, simulation of used method for modulation purposes and with sets design defined optical and electronic system. In the end is described final result, which is the fetus of pre-planned work.

V nalogi se osredoto?am na pripravo orodij za iztiskovanje profilov. Opisal sem postopek korekcije na orodju ter opredeli, kaj je potrebno narediti, da je orodje pripravljeno na iztiskovanje in kaj se naredi po kon?anem procesu proizvodnje, de je orodje pripravljeno za nadaljno obdelavo. I worked as an intern at Impol d. d. and I decided to write my diploma thesis there. The thesis focuses on the preparation of the tools for extrusion of profiles, rods, bars and tubes which are extruded intermediate products of certain dimensions and shapes I got acquainted with these products during my internship at the company.