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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Valideringsstudie av Multi-Zone Fire Model

Schagerström, Lukas January 2020 (has links)
Det finns ett flertal brandsimuleringsprogram på marknaden som används i olika utsträckning varav ett är Fire Dynamics Simulator (FDS). En av nackdelarna med FDS är att det kan ta mycket tid att göra en brandsimulering. Det finns brandsimuleringsprogram som med stor sannolikhet utför brandsimuleringar snabbare än FDS. För några av dessa brandsimuleringsprogram finns det inte någon dokumentation om hur resultaten som brandsimuleringsprogrammen producerar ställer sig mot det som skulle hända i verkligheten vid en brand, något som kallas att vara valideratdet vill säga programmen är inte validerade. Ett av dessa brandsimuleringsprogram är Multi-Zone Fire Model (MZ-Fire Model). Brandsimuleringsprogrammet MZ-Fire Model bygger på ett multizonkoncept framtaget av Suzuki et al. Multizonkonceptet har validerats i tidigare studier varav ett är en brand i tunnel men även bränder i mindre lokaler har prövats. Det finns utrymme för ökad kunskap om hur multizonkonceptet hanterar bränder i stora rumslokaler då det inte finns någon känd dokumentation kring detta. Det finns i dagsläget inte en enda studie som behandlar brandsimuleringsprogrammet MZ-Fire Model. I rapporten redogörs för simulerande av en brand i 4 olika rum av brandsimuleringsprogrammen MZ-Fire Model och FDS, dess simulerade värden är sedan jämförda mot varandra. / There are a number of fire simulation programs on the market that are used to varying degrees, one of which is Fire Dynamics Simulator (FDS). One of the disadvantages of FDS is that it can take a lot of time to do a fire simulation. There are fire simulation programs that are very likely to perform fire simulations faster than FDS. For some of these fire simulation programs, there is no documentation on how the results produced by the programs compare with what would happen in the event of a real fire, something called to bethat is they are not validated. One of these fire simulation programs is Multi-Zone Fire Model (MZ-Fire Model). The fire simulation program MZ-Fire Model is based on a multi-zone concept developed by Suzuki et al. The multi-zone concept has been validated in previous studies, one of which is a fire in a tunnel but fires in smaller premises have also been tested. There is room for increased knowledge about how the multi-zone concept handles fires in large rooms, as there is no known documentation on this. Currently, there is not a single study dealing with the MZ-Fire Model program. The report describes the simulation of a fire in 4 different rooms by the programs MZ-Fire Model and FDS, its simulated values ​​are then compared against each other.
272

3D Autoškola / Driving School - Rules of the Road

Melcer, Pavel January 2019 (has links)
This work deals with driving skills training problematics using a driving school 3D simulator, which monitors the observance of road traffic rules. Existing simulators are categorized by characteristics and described. The text contains a list of implemented rules and a summary of suitable tools. The resultant application is based on the Unreal engine and the text describes the various stages of development.
273

Design setup for haptic devices for surgery applications / Design av haptisk platform för medicinska kirurgi-simulatorer

El Musleh, Khaled January 2016 (has links)
In a way to help doctors and medical students train on performing difficult surgeries before entering the stressful operating room, DevinSense is developing a generic hardware platform for medical simulation. The system is used together with specific simulation software derived from real patient data and optimized towards the user specifications. The hardware platform will enable training for the operator to develop basic surgical skills effectively without the risk of losing the patients and avoiding the hospital daily contrails. The trainee on the simulator sees the scene displayed in real 3D-stereoscopic mode through a semi-transparent mirror and controls the surgery tools with a 6-DOF force feedback device. Thus, the simulated procedure becomes nearly identical to the real surgery. This project aims to develop a conceptual hardware platform for the medical simulator. The proposed solution should be height adjustable to different users. It must also include additional ergonomic functions such as mobility and suitable for use within the working environment. Accordingly, two conceptual prototypes are manufactured and evaluated. The first conceptual prototype is developed to check if the setup provides a good experience for the users, and to dimension the size of the components and to determine their location to set targets for the second prototype. The resulting product of the second prototype is one leg-lifting column with aluminum profile mounted on the top of it. The semi-transparent mirror, secondary monitor, haptic device and additional components are mounted on the setup to deliver the desired functions. The mechanical development is done using Autodesk Inventor. ANSYS is used to simulate the setups’ stresses and vibrational response to ensure that the system will perform optimally. MATLAB is used for mathematical modeling. The test results of the second prototype were promising where the height can be adjusted for users between 155 cm and 200 cm. Furthermore, the prototype provides stable and stiff design while operating on the simulator as well as transporting it. / För att hjälpa läkare och läkarstudenter att träna på att utföra svåra operationer, utvecklar DevinSense en generisk hårdvaruplattform för medicinska kirurgi-simulatorer. Systemet används för specifika simuleringsprogram som kommer ifrån verkliga patientdata och är optimerad med avseende på användarens specifikation. Hårdvaruplattformen möjliggör utbildning för operatören att utveckla grundläggande kirurgiska färdigheter effektivt utan risk för patienterna. Den som utbildas på simulatorn ser operationssimuleringen som en verkligt 3D-stereoskopisk bild genom en halvgenomskinlig spegel och styr kirurgiverktyget med en 6-DOF haptisk-enhet. Simuleringen kommer att kännas som en riktig operation. Syftet med projektet är att utveckla en prototyp av en haptisk plattform för en medicinsk simulator. Prototypen bör vara justerbar i höjdled för att passa olika användare. Den måste också innefatta ytterligare ergonomiska funktioner som till exempel att vara lätt att transportera. Följaktligen har två prototyper tillverkats och utvärderats. Den första prototypen utvecklades för att kontrollera om den ger en bra upplevelse för användaren, för att dimensionera komponenterna och för att bestämma deras platser. Detta för att sätta upp mål för den slutgiltiga prototypen. Den slutgiltiga prototypen har en linjärenhet som är monterad på en bottenplatta och en aluminiumprofil som är monterad ovanpå linjärenheten. Den halvgenomskinliga spegeln, sekundära bildskärmen, haptiska enheten och ytterligare funktionsenheter har även monterats på aluminiumprofilen. Autodesk Inventor användes för att designa prototypen. ANSYS användes för att analysera spänningar och vibrationsbeteende hos prototypen för att säkerställa att systemet kommer att fungera tillfredställande. MATLAB användes för matematisk modellering. Testresultaten för den andra prototypen blev lovande. Höjden kan justeras för användaren, som är mellan 155 och 200 cm lång, den är stabil när användaren använder haptikenheten och den är även stabil när användaren ska förflytta prototypen till ett annat rum.
274

Effekter av körerfarenhet på självskattning och riskbedömning / Effects of driving experience on self- and risk assessment

Åström, Jonna January 2021 (has links)
Tidigare forskning har visat att unga i jämförelse med äldre förare, har en mer positiv inställning till att ta risker och håller en generellt högre hastighet i trafiken (Hatfield & Fernandes, 2009). Forskning har också visat att unga förare, framför allt män har en tendens att överskatta sin körförmåga (De Craen et al., 2011). Självskattning kan mätas medolika metoder, något som bland annat Sundström (2008) menar kan påverka resultatet. Flera studier har visat att unga förare kan göra en mer exakt bedömning av sin körprestation när de bedömer en specifik körförmåga snarare än när de jämför deras allmänna körprestation med den genomsnittliga förarens (Mynttinen et al., 2009a; Mynttinen et al., 2009b). Syftet med den aktuella studien var att undersöka om självskattad körprestation påverkas av körerfarenhet samt om det fanns något samband mellan körprestation och självskattad körprestation eller riskbedömning. Studien ämnade att göra detta genom att besvara följande frågeställningar 1. Finns det ett samband mellan ålder och självskattad körförmåga? 2. Finns det ett samband mellan körprestation och självskattad körprestation? 3. Finns det ett samband mellan körprestation och riskbedömning? Totalt deltog 48 förare i studien, där hälften var i åldrarna 18–25 och resterande i åldrarna 45–60. Experimentet genomfördes hos Statens väg- och transportforskningsinstitut (VTI) där deltagarna fick köra ett 20 minuter långt scenario i en stationär körsimulator. Innan, under och efter körningen ombads deltagarna att skatta sin körprestation och upplevda risk. Efter körningen hölls en kompletterande intervju. Resultaten visade att det inte fanns något signifikant samband mellan ålder och självskattad körförmåga, något som tyder på att körerfarenhet inte hade någon inverkan på självskattning. Det fanns en antydan till samband mellan körprestation och både självskattning och riskbedömning. För riskbedömning generellt fanns en potentiell effekt för både ålder och kön, något som inte fanns hos självskattad körprestation. Studien ger en indikation på samband för både körprestation och självskattad körprestation samt körprestation och riskbedömning som behöver studeras vidare med ett större underlag. / Previous research has shown that young in comparison with older drivers, have a more positive attitude towards taking risks and maintain a generally higher speed in traffic (Hatfield & Fernandes, 2009). Research has also shown that young drivers, especially men, tend tooverestimate their ability to drive (De Craen et al., 2011). Self-assessment can be measured using different methods, something that Sundström (2008), with others,believes can affect the result.Several studies have shown that young drivers can make a more accurate assessment of their driving performance when assessing a specific driving ability rather than when they are assessingtheir general driving performance against the average driver (Mynttinen et al., 2009a; Mynttinen et al., 2009b). The purpose of the current study was to investigate whether self-rated driving performance was affected by driving experience and whether there was any correlation between driving performance and self-rated driving performance or risk assessment. The study intended to do this by answering the following questions 1. Is there a correlation between age and self-rated driving ability? 2. Is there a correlation between driving performance and self-rated driving performance? 3. Is there a correlation between driving performance and risk assessment? A total of 48 drivers participated in the study, half of them were in the age group 18–25 and the rest were in the age group 45–60. The experiment was carried out at the Swedish National Road and Transport Research Institute (VTI) where the participants completed a 20-minute long driving scenario in a stationary simulator. Before, during and after the drive, participants were asked to estimate their driving performance and perceived risk. After that, a supplementary interview was held. The results showed that there was no significant relationship between age and self-rated driving ability, which indicates that driving experience had no effect on self-assessment. There was a hint of correlation between driving performance and both self-assessment and risk assessment. For risk assessment in general, there was an effect for both age and gender, something that did not exist in self-rated driving performance. The study provides an indication of a relationship between both driving performance and self-rated driving performance, as well as driving performance and risk assessment that need to be studied further with a larger sample.
275

Evaluation of Motion Cueing Algorithms for a Limited Motion Platform Driver-in-Loop Simulator

Sekar, Rubanraj 13 August 2020 (has links)
No description available.
276

High-Performing Cloud Native SW Using Key-Value Storage or Database for Externalized States / Högpresterande moln-nativ mjukvara med användning av nyckelvärdeslagring eller databas för externaliserade tillstånd

Sikh, Ahmed, Axén, Joel January 2023 (has links)
To meet the demands of 5G and what comes after, telecommunications companies will need to replace their old embedded systems with new technology. One such solution could be to develop cloud-native applications that offer many benefits but are less reliable than embedded systems. Having the different units in the 5G system store their state, or their operational context, in cloud-based databases could reduce downtime in case of failing processes, but various database systems have their advantages and disadvantages. Thus, the choice of implementation must be carefully considered.   This study primarily aims to create a simulator that can measure latency, or the time it takes to write or read dummy data to or from one of two different kinds of databases. Its secondary aim is to produce use cases that mimic situations that a database for state data would need to handle and to collect measurements from them with the help of the simulator.   The simulator was implemented using C++17 and contains a simulator object and separate database clients. The actors representing the units interacting with a 5G network were created by the clients and their state data was stored in either Redis or PostgreSQL databases. Various use cases were designed with the instruction from Ericsson to simulate real-life scenarios and to measure latencies. Quantitative data analysis was performed on the collected data to compare the performances of Redis and PostgreSQL databases in the different use cases.   The study found that Redis on average worked the fastest and that its latency was largely the same regardless of data sizes, while PostgreSQL's latencies, and thus the differences between the databases, varied more depending on the scenario.   The results of the study show that Redis is the one of the two databases that operates more consistently and predictably, which may partly be explained by the fact it is mainly based in the RAM, while PostgreSQL is mainly disk-based.   Future work could involve testing the databases under higher workloads, exploring what would be the impact of running simulations in environments with reduced RAM and not letting Redis use it to its full advantage, and maybe analyzing more latency figures by creating new use cases and running them. Future work can also include an investigation of the effect of Redis database crashes. Moreover, the simulator implementation allows for changing to other types of databases.
277

Bicycle simulator study with older adults

Suing, Martina 02 January 2023 (has links)
This feasibility study reports on the first experimental experiences with the BASt bicycle simulator. Since older cyclists represent an important target group in road safety due to their increased vulnerability, both cyclists aged 65 and over (experimental group: EG) and, by way of comparison, middle-aged test subjects aged 25--50 (cont.rol group: CG) were included in the study. The study aims to gain initial insights into the prerequisites, possibilities and limitations for using the bicycle simulator to observe cycling behaviour. In addition to the actua1 test ride the three preceding pra.ctice rides were also evaluated. A comparable study with older adults has already been conducted with the BASt car simulator.
278

Methods for validating a flight mechanical simulation model for dynamic maneuvering / Metod för validering av flygmekanisk simulator för dynamisk manövrering

Senneberg, Sofia January 2021 (has links)
Flight mechanical simulators play an important role in the design steps during development of a new aircraft. To be able to simulate and evaluate flight mechanical characteristics during development it is important to minimize development time and cost while keeping flight safety high during early flights. The aim of the project presented in this thesis is to develop a method for validating a flight mechanical simulator against flight test data from dynamic maneuvering. An important part in this thesis is about how deviations in the result data can be found and analyzed, for example deviations between aircraft individuals or store configurations. The work presented here results in a good model for comparison of a big amount of data where it is easy to backtrace where the deviation occurs. / Flygmekaniska simulatorer är av stor betydelse under utvecklingen av ett nytt stridsflygplan. Möjligheten att simulera och utvärdera under tidens gång har stor betydelse både ur tid- och kostnadsbesparings perspektiv men även ur flygsäkerhetsperspektiv när det är dags för första flygning. Syftet med det här projektet är att utveckla en metod för jämförelse mellan simulering och flygprov för att validera hur bra den flygmekaniska simulatorn kan förutspå flygplansbeteende. En viktig del i projektet syftar till hur skillnader i resultaten kan hittas och analyseras, till exempel skillnader mellan olika flygplansindivider eller lastkonfigurationer. Arbetet presenterat här har resulterat i en modell som är bra för jämförelse av en stor mängd data där det är enkelt att spåra var skillnaderna har uppstått.
279

Análises e ajustes adaptativos da proteção aplicada a um sistema de distribuição na presença de geração distribuída / Analysis and adaptive adjustments of the protection applied to a distribution system in the presence of distributed generation

Furlan, Renan Hermogenes 24 May 2019 (has links)
A proteção de Sistemas de Distribuição (SDs) é de fundamental importância considerando as condições adversas de operação e faltas elétricas a que os mesmos podem estar submetidos. A crescente utilização de Geradores Distribuídos (GDs) conectados aos SDs e as possíveis operações em ilhamento promovem interferências consideráveis aos dispositivos de proteção. Dessa forma, evidencia-se a importância de estudos para esses novos cenários. Neste contexto, esta pesquisa tem como proposta analisar o desempenho do sistema de proteção, quando na presença de uma elevada contribuição de geração distribuída, e aprimorar a proteção tradicional, quando tem-se a mudança do cenário de operação para o modo ilhado. Sendo assim, evidencia-se através de simulações no Real-Time Digital Simulator (RTDS) os efeitos da perturbação nos Relés de Sobrecorrente (RSC). Na metodologia desenvolvida implementa-se um sistema de proteção adaptativo, cujos parâmetros são definidos por um algoritmo de otimização. Também são adicionadas as proteções associadas aos GDs, recomendadas por norma. Tal prática é dificilmente abordada em trabalhos correlatos a pesquisa, no entanto através dos resultados observou-se que esses dispositivos podem influenciar na respostas dos elementos de proteção implementados nos SDs. Como diferencial também buscou-se implementar todo o sistema de controle dos GDs e utilizou-se da simulação em malha fechada com relés comerciais, afim de aproximar a modelagem da realidade encontrada nos SDs. Por fim, evidenciou-se que a utilização de relés adaptativos pode viabilizar a operação em ilhamento. / The protection of Distribution Systems (DSs) is of fundamental importance, considering the adverse operating conditions and electrical faults to which they may be submitted. The increasing usage of Distributed Generators (DGs) connected to DSs, and possible islanded operations promote considerable interference to protective devices. Thus, it is evident the importance of studies for these new scenarios.This research aims to analyze the performance of the protection system, when in the presence of a massive contribution of distributed generation, and to improve the traditional protection when there is a change from the operating scenario to island mode. Thus, via simulations, carried out in the Real-Time Digital Simulator (RTDS), the effects of the disturbance on the Overcurrent Relays (OCs) were evident. The developed methodology implements an adaptive protection system, whose parameters are defined by an optimization algorithm. The protections associated with DGs were also added, as recommended by the standard. This practice is hardly approached in related studies however, through the results, it was observed that these devices could influence the responses of the protective elements implemented. The closed-loop simulations carried out considering the standard controls systems regarding DGs and commercial intelligent eletronic devices, ensuring the test bed verisimilitude to actual DSs. This approach is not standard on the literature related. Finally, it was evidenced that the use of adaptive relays can contribute to the islanded operation.
280

Lógica fuzzy aplicada na melhoria da proteção digital de geradores síncronos / Fuzzy logic applied in synchronous generators digital protection improvement

Renato Machado Monaro 28 February 2013 (has links)
Este trabalho propõe um novo método de proteção de geradores síncronos baseado em inteligência artificial, mais especificamente lógica fuzzy, com o propósito de melhorar a proteção destes componentes vitais aos sistema elétricos de potência. Um sistema elétrico de potência completo composto por geradores, linhas de transmissão e cargas foi simulado através do Real Time Digital Simulator para fornecer dados para realização de testes e validação do algoritmo de proteção inteligente. Adicionalmente, foram desenvolvidos dois esquemas experimentais que proporcionaram a obtenção de um conjunto extensivo de ensaios de faltas internas em dois geradores síncronos reais, com o objetivo de fornecer dados para comprovar a eficácia da proteção proposta. Um sistema integrado de software e hardware cujo objetivo é servir de plataforma para desenvolver e executar em tempo real algoritmos de proteção aplicados foi desenvolvido. Esse sistema integrado foi utilizado nos testes embarcados em tempo-real do algoritmo de proteção desenvolvido. Apresenta-se também um arranjo composto por funções de proteção tradicionais mais utilizadas em campo, as quais serviram como base de comparação de desempenho para o esquema de proteção inteligente desenvolvido. Os resultados apresentados mostram que o método de proteção inteligente proposto é mais sensível para detectar instantaneamente faltas fase-terra em geradores síncronos com aterramento de alta-impedância, além de ser capaz de identificar faltas entre-espiras e entre-caminhos / This work presents the development of a synchronous generator protective technique based on artificial intelligence, specifically fuzzy logic, in order to improve the protection of these vital components of the electric power system. A complete electric power system composed of generators, transmission lines and loads was simulated using the Real Time Digital Simulator to provide data for testing and validating the intelligent protection algorithm. Additionally, an extensive set of internal fault experiments conducted on two actual synchronous generators provided oscillograms to demostrate the proposed protection effectiveness. An integrated hardware and software system whose purpose is to serve as a platform for developing and executing real-time protection algorithms is presented. This integrated system was used for real-time embedded testing of the protection algorithm developed. An arrangement composed of traditional protection functions most used in the field is also presented, this arrangement served as a comparison basis for the intelligent protection scheme performance. The results show that the intelligent protection is more sensitive to detect instantly ground faults in synchronous generators with high-impedance grounding, it is also shown that the proposed scheme is able to identify inter-turns and inter-circuits faults

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