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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.
111

Dispositivo para medição e teste de transmitância luminosa e semafórica em óculos de sol de acordo com a norma brasileira - ABNT NBR ISO 12312-1:2015 / Device for luminous and traffic lights transmittance evaluation in sunglasses according Brazilian Standard - ABNT NBR ISO 12312-1:2015

Loureiro, Artur Duarte 06 November 2017 (has links)
A classificação por categoria de 0 a 4 para óculos de sol determina quão claras ou escuras são suas lentes. A norma brasileira, ABNT NBR ISO 12312-1, exige, entre outros requisitos, testes de transmitância da luz visível em óculos de sol (categoria), para que estes sejam classificados como adequados ou não para direção de automóveis. Medidas do grau de escurecimento das lentes de um par de óculos de sol e da atenuação luminosa das luzes de sinais semafóricos são testes propostos para este item da norma. Porém, o público, em geral, não possui meios de testar seus próprios óculos. Um teste padrão de transmitância é trabalhoso, demorado e requer um espectrofotômetro e um profissional treinado. O objetivo deste trabalho é desenvolver um dispositivo portátil capaz de realizar testes de transmitância luminosa e semafórica de acordo com a norma brasileira sendo rápido, preciso e intuitivo, realizando os testes de forma automática sem exigir do usuário qualquer treinamento prévio. Diferentemente dos dois sistemas anteriormente desenvolvidos no Laboratório de Instrumentação Oftálmica (LIO), para testes de transmitância, este dispositivo é embarcado e atende à norma atual lançada em 2015, que não estava em vigor na época em que os demais foram desenvolvidos. O desafio para se construir um sistema embarcado é a combinação de fontes luminosas e sensores necessária para se obter padrões espectrais similares aos da norma. Foi desenvolvido e construído um protótipo microcontrolado usando a combinação de um LED branco com o sensor TCS3472. Esta combinação gera quatro funções de ponderação distintas, que foram combinadas linearmente resultando em funções de ponderação próximas às da norma para as medições desejadas. Foram medidos transmitância luminosa e quocientes de atenuação visual para luzes semafóricas de 128 lentes de óculos de sol com o protótipo e com um padrão-ouro, o espectrofotômetro Cary 5000 da VARIAN. O método de Bland-Altman foi usado para análise de concordância entre ambos os métodos de medição. Para valores de transmitância luminosa, foram adotados 0,5 % e 6 % como valores a partir dos quais o valor absoluto do viés é significativo e a amplitude do intervalo de confiança, grande, respectivamente. Para valores dos quocientes de atenuação, 0,1 e 0,4; respectivamente. O viés não foi significativo para nenhuma das medições. O intervalo dos limites de concordância de 95% foi amplo para medição de transmitância luminosa e do quociente para luz azul e estreito para as demais, considerando-se os valores-limites previamente definidos para vieses e para limites de concordância. Assim, dentro da tolerância definida, medições com o protótipo e com o padrão-ouro são equivalentes para quociente de atenuação para as luzes vermelha, amarela e verde. Apesar de nem todas as medições do protótipo serem equivalentes às do padrão-ouro, os resultados apresentaram boa exatidão, com apenas 5 das 128 lentes classificadas erroneamente quanto à adequação para direção (2 por transmitância luminosa, 1 por luz vermelha e 2 por luz azul). O protótipo proporciona ao público uma forma de obter informações sobre seus próprios óculos de sol e sobre a importância do uso de óculos adequados durante a direção de veículos. / Category rating ranging from 0 to 4 determines how light or dark sunglasses lenses are. Category measurements and how much traffic signal colors are attenuated are required tests by brazilian standard ABNT NBR ISO 12312-1 and are known as transmittance tests. Brazilian standard also establishes requirements for sunglasses to be suitable for driving. However, people often do not have means to measure their own sunglasses. A standard transmittance test is laborious, time-consuming and it requires a spectrophotometer and a skilled technician. The goal of this study was to develop not only a single device capable to perform luminous and traffic light transmittance tests according to brazilian standard, but also an easy-to-use, quick, accurate and portable device, which runs the tests by itself in a way anyone can operate it without any training. Unlike the two systems previously developed in the Ophthalmic Instrumentation Laboratory (LIO) for transmittance tests, that one does not contain a computer, but a microcontroller. Also, it complies with current standard, which has been released in 2015, and previous systems are based on 2013 standard version. A microcontrolled prototype was developed and built using a white LED and TCS3472 sensor combination. This combination generates four different weighting functions that were linearly combined resulting in weighting functions similar to the standard ones for luminous and traffic light transmittances. Using our prototype and a gold standard (VARIAN Cary 5000 spectrophotometer), luminous transmittance and relative attenuation quotients for traffic lights were measured in 128 sunglasses lenses. Bland-Altman method was used to assess concordance between both measurement methods. The bias was insignificant for all measurement and the limits of agreement were broad for luminous transmittance and for relative attenuation quotient for blue light detection, and narrow for all the others. Thus, within the predefined tolerance, prototype measurements are equivalent to gold standard ones for relative attenuation quotients for red, yellow and green light detection. Despite not all prototype measurements being equivalent to gold standard ones, results were accurate; only 5 from 128 lenses were incorrectly classified as to suitability for driving (2 for luminous transmittance, 1 for red light quotient and 2 for blue light quotient). Our device aims to provide to general public a mean to obtain information about their own sunglasses and the importance to use suitable sunglasses while driving.
112

Ljuslyktan Ballongen : / The Balloon : a Candle Lantern

Olofgörs, Erik January 2012 (has links)
During my final examination project, I have been working with a design process to develop a new set of candle lanterns for the company Sagaform AB. This company has a large and significant role on the Swedish interior design and retail market. The assignment was developed when the company stated that they would like to supplement and expand its existing range of products.  The research and surveys I have done have helped me to create eight different concepts and one of them ready to compete with the existing candle lanterns on the market.  The result of my concept proposal expected to be included in Sagaform’s 2013 spring catalogue. During the project I have developed 3D-rendered images, a physical model, and a solid foundation for making prototypes.  The Balloon has an attractive design language that fits both every day and more festive events. Designed to encourage the user to a happier, more well-being and relaxing lifestyle. The balloon is available in two sizes and in different bright colors that are adapted to tea and block candles, to be safely used indoors and outdoors. / Jag har under mitt examensprojekt arbetat med en designprocess för att utveckla en ny serie ljuslyktor åt Sagaform AB. Företaget har en stor och betydelsefull roll på den svenska inrednings- och detaljhandeln. Uppdraget togs fram när företaget gav mig i uppgift att komplettera och bredda deras befintliga utbud av produkter. Den information jag tagit del av genom mina skrivbordsundersökningar, analyser och enkäter har hjälpt mig att skapa åtta olika koncept varav en av dessa som utvecklats full ut och idag är redo att tävla mot existerande produkter på den konkurrenshårda marknaden. Resultatet blev ett koncept som är planerat att vara med i Sagaforms sortiment under våren 2013. Under projektets gång så har jag tagit fram CAD/3D-renderade bilder, en fysisk modell samt ett gott underlag för att tillverka prototyper. Ljuslyktan Ballongen har ett tilltalande formspråk som passar både till vardagen och festligare arrangemang. Designad för att uppmuntra användaren till en lyckligare, mer välbefinnande och avkopplande livsstil. Ballongen finns i två storlekar och i olika klara färger som är anpassade efter värme- och blockljus för att säkert kunna användas inom- och utomhus. / 2012;50
113

應用禁忌基因演算法劃分路燈巡修範圍之研究 / Using tabu-genetic algorithms in street lights patrolling and maintaining region layout

曾斐瑜, Tseng, Fei Yu Unknown Date (has links)
路燈巡修作業的落實與否,影響路燈維護的效率及品質,為能有效提升路燈管理之效能,近來管理階層逐漸重視路燈巡修區域的規劃。然而巡修區域的劃分,多依據主管人員之經驗調派,缺乏系統化、科學化的分析與評估,往往使人力資源無法有效運用,形成勞逸不均的現象,進而影響維護品質,因此如何以科學的方法劃分路燈巡修區域是個重要的課題。 本研究的重點在於針對現行路燈巡修區域劃分之缺點,提出一個新的方法,使各區域管理員巡修時間差達到最小化,以解決現行區域劃分的不合理現象。我們所提出的劃分法,以基因演算法進行演算,並加入禁忌名單改善基因演算法區域搜尋效率不佳的缺點,提升整體的求解速度,同時將路燈維護數量、故障率、維護時間、交通時間、巡修次數等影響因子,納入巡修時間的計算公式中,使劃分後各區的巡修時間差達到最小化。 本研究以台北市政府公園路燈工程管理處的路燈東區分隊為實作對象,在考慮不同的基因演化條件下,分別比較巡修區域劃分前後之變化情況,由實驗結果顯示,我們提出的劃分方法,確實使各區管理員的巡修時間差不超過3%,並且滿足巡修不跨區作業之需求。 / The efficiency and quality of street lights maintenance is influenced by the operation of patrolling and maintaining. In order to raise the working efficiency of maintenance crew, the supervisors pay more attention to region redistricting recently. The formor region districting methods normally base on human experiences without systematic or scientific evaluations, These facts, not only result in human resources wasting and uneven labor allocations, but also affecting the maintenance qualities. Therefore, it is a crucial issue to make region redistricting more scientifically. The key point of this research is to provide a systematic redistricting mechanism to minimize the patrolling time variation for all the districts. Our mechanism is based on genetic algorithm to reduce the patrolling time differences. Tabu search list is used to improve the searching efficiency of general genetic algorithms. Various factors were integrated in our mechanism to minimize the patrolling time variations. These factors include total number of street lights, average failure rate, average maintenance time, traffic delay, patrolling and maintaining frequency, etc. We used districts covered by the East Branch of SET/PSO of Taiepi City Government as the examples in our studies. The experimental results show that, using our mechanism, the patrolling time difference is reduced to 3% and maintenance crews can perform their duty without crossing region boundary.
114

Influência do tipo de ponteira utilizada na fotoativação sobre o grau de conversão, dureza e resistência á compressão de resinas compostas /

Caldas, Marília Regalado Galvão Rabelo. January 2010 (has links)
Resumo: O objetivo deste trabalho, dividido em dois estudos, foi avaliar: (1) a influência dos tipos de ponteiras (fibra óptica e polímero) utilizadas em um aparelho fotoativador à base de LED (Ultrablue IS - DMC) sobre o grau de conversão e dureza de uma resina composta microhíbrida (FiltekTM Z250) e uma nanoparticulada (FiltekTM Supreme XT); e (2) a influência dos tipos de ponteiras (fibra óptica e polímero) utilizadas em um aparelho fotoativador à base de LED (Ultrablue IS - DMC) sobre a resistência à compressão de uma resina composta microhíbrida (FiltekTM Z250) e uma nanoparticulada (FiltekTM Supreme XT). No primeiro estudo, para os testes de grau de conversão (GC) e dureza, cinco corpos-de-prova com 4 mm de diâmetro e 2 mm de espessura (ISO 4049), foram confeccionados para cada grupo avaliado. O grau de conversão foi analisado pelo Espectrofotômetro Nexus - 470 FT-IR. Para o teste de dureza Vickers, os corpos-de-prova foram levados ao Durômetro Micromet 2100 (Buehler, EUA) onde foi utilizada uma carga de 50 gramas força (gf) e tempo de 30 segundos. Para cada corpo-de-prova oito medidas foram realizadas nas superfícies de topo e base. Os dados obtidos para o GC e dureza foram analisados estatisticamente pelo teste de Análise de Variância (ANOVA) e Tukey. No segundo estudo, para o teste de resistência à compressão foram confeccionados oito corpos-de-prova com 8 mm de altura e 4 mm de diâmetro. O teste foi realizado na máquina de ensaio universal EMIC com célula de carga de 5 kN à velocidade de 0,5 mm/min. Os dados obtidos foram analisados estatisticamente pelo teste ANOVA e o teste Tamhane. Os resultados demonstraram que o GC e dureza foram influenciados pelas ponteiras, sendo a dureza também influenciada pelo tipo de resina composta utilizada. A resina composta microhíbrida fotoativada com a ponteira de fibra óptica apresentou maiores valores do GC e dureza... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this work, divided into two studies, was evaluate: (1) the influence of types of light guide tips (fiber optic and polymer) used in a photo-activation based on LED (Ultrablue IS - DMC) on the degree of conversion and hardness one microhybrid FiltekTM Z250 and one nanofilled FiltekTM Supreme XT composite resins; and (2) the influence of types of light guide tips (fiber optic and polymer) used in a photo-activation based on LED (Ultrablue IS - DMC) on the compressive strength of one microhybrid FiltekTM Z250 and one nanofilled FiltekTM Supreme XT composite resins. In the first study, to test the degree of conversion (GC) and hardness, five samples 4 mm in diameter and 2 mm in thickness (ISO 4049) were made for each group evaluated. The degree of conversion was evaluated by Fourier transform infrared spectroscopy (FT-IR). For the Vickers hardness test, the samples were brought to the durometer Micromet 2100 (Buehler, USA) where was used a load of 50 gram force (gf) and time of 30 seconds. For each sample test measurements were performed eigth measures on the surfaces of top and bottom. The data obtained for the GC and hardness test were statistically analyzed by Analysis of Variance (ANOVA) and Tukey's test. In the second study to test the compressive strength eight samples (4 mm in diameter and 8 mm in thickness) were made for each group evaluated, and the test was conducted in a universal testing machine EMIC with load cell 5 kN and speed of 0,5 mm/min. The data were statistically analyzed by ANOVA test and Tamhane's test. The results showed that the GC and hardness were influenced by the light guide tip, and the hardness also influenced by the type of resin used. The microhybrid composite resin photo-activated with the fiber optic light tip had higher values of GC and hardness. The lowest values of GC and hardness were observed with nanofilled composite resin photoactivated... (Complete abstract click electronic access below) / Orientador: Marcelo Ferrarezi de Andrade / Coorientador: Alessandro Nara de Souza Rastelli / Banca: Silmara Aparecida Milori Corona / Banca: José Roberto Cury Saad / Mestre
115

Geoinformação para estudos demográficos: representação espacial de dados de população na Amazônia Brasileira. / GEOINFORMATION AND DEMOGRAPHIC STUDYES: SPATIAL REPRESENTATION OF POPULATION DATA OVER THE BRAZILIAN AMAZÔNIA.

Silvana Amaral Kampel 15 December 2003 (has links)
Esta tese propõe o uso da geoinformação a serviço da demografia tomando-se a distribuição da população na Amazônia Brasileira como objeto de estudo. Foram desenvolvidos métodos baseados em dados de sensoriamento remoto e técnicas de análise espacial para representar a população em superfícies de densidade. O objetivo geral foi verificar a utilidade dos dados de sensoriamento remoto para compor a base do processo de redistribuição da população, em comparação com métodos tradicionais. Especificamente, foram utilizadas imagens de luzes noturnas do sistema DMSP/OLS para a Amazônia Legal, e imagens dos sistemas CCD-CBERS1 e TM-Landsat, para a escala municipal. Inicialmente, um mosaico de imagens de luzes noturnas DMSP/OLS foi avaliado quanto à capacidade de detectar presença e atividade humana na região. As relações lineares entre pixels de luzes DMSP e população urbana, área urbanizada e consumo de energia elétrica obtidas, motivaram o desenvolvimento de um produto de luzes noturnas mais recente e adequado para estudos de distribuição de população. A análise deste mosaico indicou o potencial e as restrições da informação de luzes noturnas para estimar a evolução dos valores de população urbana. Um novo método para interpolar e redistribuir população utilizando informações de luzes noturnas, denominado DMSPop_M foi apresentado. A superfície de densidade populacional resultante mostrou-se uma opção intermediária entre as superfícies obtidas através das técnicas tradicionais para interpolar população, e a representação através dos setores censitários. Para a escala municipal, outro método multivariado para distribuir população foi desenvolvido para Marabá - PA. Dados provenientes da classificação digital de imagens CBERS e Landsat e outros dados geográficos foram selecionados como variáveis indicadoras da presença de população. Através de técnicas de pertinência e inferência Fuzzy a população dos setores censitários foi redistribuída em superfícies de densidade populacional. A superfície que melhor representou a distribuição populacional foi aquela obtida através de média simples das variáveis. O método desenvolvido poderá ser aplicado para modelos mais robustos em que as superfícies resultantes refletirão a relação entre variáveis proposta. Os dados de sensoriamento remoto foram fundamentais para incluir a heterogeneidade espacial nos métodos desenvolvidos. Finalmente, este trabalho contribui para que estudos de modelagem, e planejamento para a região Amazônica possam incluir adequadamente a dimensão humana no que se refere à distribuição e representação de sua densidade populacional. / This thesis presents the use of geoinformation as a valuable tool for demographic studies where the subject of interest is the population distribution over the Brazilian Amazon. Population density surfaces based on remote sensing data and spatial analysis techniques are developed as an alternative approach to represent population distribution. Remote sensing data is hypothesized as the basis for disaggregation methods to distribute population in regular cells. Specifically, imagery from DMSP/OLS night-time lights is used at global scale and from CCD-CBERS1 with TM-Landsat imagery at municipal scale. First, DMSP/OLS data is evaluated about the relations between night-time lights and human activities in Amazônia. Significative linear correlations between night-time lights and urban population, electrical power consumption and urban area are obtained. Thus, alternative techniques to generate a night-time lights mosaic are proposed and a new mosaic is generated to be used as a reference of urban population distribution. The analysis of this new DMSP mosaic reveals its potential and restrictions to estimate and to monitor the annual evolution of urban settlements. A new interpolation method to generate population density surface is developed using night-time lights data. The resultant surface, comparing to the usual interpolation methods for population is considered an intermediary option between the traditional techniques and the surface representing population data from a higher scale (the census sector). At municipal scale, a multivariate method to distribute population inside the municipal boundaries is developed for Marabá, state of Pará. CBERS and Landsat imagery and other geographical data are selected as indicator variables of human presence. These variables are converted to Fuzzy memberships and related to each other towards average and Fuzzy operators. The census sector population is redistributed in the population density surfaces. The best surface is obtained from simple average of the indicator variables. The proposed method can support different models and its population density will reproduce the consistence of them. Finally, this thesis contributes to represent the population distribution at global and municipal scale at the Brazilian Amazon. The methods and results obtained here will be helpful for any environmental modeling study in the Amazon region that cares for the local population that has been living there all along.
116

Matemática na música a escala cromática e as progressões geométricas / Mathematics in music chromatic scale and geometric progressions

Teixeira, Alexandre Carlos da Silva 26 June 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-22T14:20:36Z No. of bitstreams: 2 Dissertação - Alexandre Carlos da Silva Teixeira - 2015.pdf: 5570395 bytes, checksum: 56c1a16748accf85c9390695464810aa (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-22T14:22:35Z (GMT) No. of bitstreams: 2 Dissertação - Alexandre Carlos da Silva Teixeira - 2015.pdf: 5570395 bytes, checksum: 56c1a16748accf85c9390695464810aa (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-10-22T14:22:35Z (GMT). No. of bitstreams: 2 Dissertação - Alexandre Carlos da Silva Teixeira - 2015.pdf: 5570395 bytes, checksum: 56c1a16748accf85c9390695464810aa (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-06-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This paper presents a proposal for relationship studies between mathematics and music, a relationship that has been established since the dawn of humanity, and could be seen more clearly from the studies developed by Pythagoras. We approach the evolution of music in the historical context and introduce the basics of music theory, essential to establishing relationships with mathematics. Our e orts were focused on instruments with strings, by which present a relationship between a musical scale, called Chromatic and geometric progressions; also we present a relationship between musical intervals and right triangles. We present a mathematical relationship between music and colors, through their respective frequencies of sound and light. Also we address the present mathematics in the construction of some instruments with strings, via Golden Proportion, and nished the work presented some proposals for activities that can be worked in the classroom, aimed at high school students. / Este trabalho traz uma proposta de estudos da relação existente entre a Matemática e a Música, relação esta que foi estabelecida desde os primórdios da humanidade, e pôde ser observada de forma mais clara a partir dos estudos desenvolvidos por Pitágoras. Abordamos a evolução da Música no contexto histórico e introduzimos as noções básicas de teoria musical, essencial ao estabelecimento de relações com a Matemática. Nossos esforços foram focados nos instrumentos com cordas, pelos quais apresentamos uma relação entre uma escala musical, denominada Cromática, e as progressões geométricas; também apresentamos uma relação entre intervalos musicais e os triângulos retângulos. Apresentamos uma relação matemática entre a Música e as cores, por meio de suas respectivas frequências de som e luz. Também abordamos a matemática presente na construção de alguns instrumentos com cordas, via Proporção Áurea, e nalizamos o trabalho apresentando algumas propostas de atividades que podem ser trabalhadas em sala de aula, voltadas para alunos do Ensino Médio.
117

Současný stav a směry rozvoje metod a technického zabezpečení navigace civilních letadel po ploše letiště / Existing state-of-the art and development tendencies of methods and technologies in the field of aircraft movement control along aerodrome surface

Zubrvalčík, Jan January 2021 (has links)
This diploma thesis deals with navigation on airport surface. In thesis there are described main surveillance systems, which are used for navigation on airport surface and systems for prediction and avoiding collisions. For all systems is listed principle of action, their usage, advantages and disadvantages and informations, which are provided by these systems. In last chapter there are compared properties of main surveillance systems.
118

Neue Ansätze zur Nutzung von Induktionsschleifen-Daten an Lichtsignalanlagen: Minimierung von Fahrzeughalten und Schätzung von Kfz-Wartezeiten

Tischler, Kathleen 10 February 2016 (has links)
Die vorliegende Dissertationsschrift widmet sich zwei Zielen: Mittels Induktionsschleifen-Detektoren einerseits die Verkehrsregelung an Knotenpunkten durch die Minimierung von Fahrzeughalten zu verbessern, und andererseits eine Veränderung der Verkehrsqualität durch die Schätzung von Kfz-Wartezeiten automatisiert zu erheben. Im ersten Teil wird ein modellbasiertes Steuerverfahren entwickelt, das Grünzeiten verkehrsabhängig und lokal anpasst. Es kann sehr gut in eine übergeordnete Steuerung zur Koordinierung in Verkehrsnetzen eingebunden werden und überlässt dieser die Optimierung von Phasenfolgen, Umlauf- und Versatzzeiten. Um auch bei hohen Auslastungen Kapazitäten bestmöglich zu nutzen, priorisiert es zunächst die Leerung von Warteschlangen. Anschließend erfolgt die Anpassung der Grünzeiten zwischen einer minimalen und maximalen Dauer so, dass Fahrzeughalte minimiert werden. Dafür werden Detektoren in ausreichender Entfernung im Zufluss einer Kreuzung verwendet, um Fahrzeugankünfte an der Haltelinie für die aktuelle und die nächste Phase zu prognostizieren. Bei der sich anschließenden Bilanzierung potenzieller Fahrzeughalte und der Wahl des günstigsten Umschaltzeitpunktes kann auf zusätzliche Modellannahmen verzichtet werden. Die Simulationsergebnisse zeigen, dass bei einer Minimierung der Fahrzeughalte gleichzeitig eine Reduktion von Wartezeiten möglich ist. Im zweiten Teil werden Kfz-Wartezeiten auf Basis der meist bereits vorhandenen Induktionsschleifen-Detektoren im Zufluss und im Abfluss einer Kreuzung geschätzt. Dafür werden die Zeitpunkte der Fahrzeugüberfahrten an einem Zufluss- und einem Abflussquerschnitt getrennt gemessen werden. Aus ihnen wird jeweils ein mittlerer Überfahrzeitpunkt ermittelt und nach Berücksichtigung der freien Fahrzeit eine mittlere Wartezeit geschätzt. Messintervalle an beiden Querschnitten, die um die mittlere freie Fahrzeit versetzt sind, sowie eine unbedingte Warteschlangenleerung am Ende einer Messung sollen sicherstellen, dass potenziell dieselben Fahrzeuge erfasst werden. Auf eine Fahrzeugwiedererkennung und damit auf eine Ausrüstung mit zusätzlicher Technik kann dadurch verzichtet werden. Damit sich das Verfahren für den Praxiseinsatz eignet, muss es möglichst robust gegenüber zufälligen Detektorfehlern sein. Dafür wird ein Fehlermodell entwickelt und mögliche Abweichungen gegenüber einer korrekten Messung untersucht. Aufgrund der unabhängigen Berechnung von mittleren Überfahrzeiten aus der getrennten Messung im Zufluss und im Abfluss zeigt sich, dass zufällige Fehler nicht zu systematischen Abweichungen in der Wartezeitschätzung führen.
119

Polisiära och lagstiftande åtgärder i syfte att öka gångtrafikanters trafiksäkerhet : En översiktsstudie / Police and legislative measures with the aim of increasing road safety for pedestrians : A scoping review

larsson, dennis January 2023 (has links)
Background: The whole of society is facing major challenges regarding the ongoing climate change and the possibility of creating sustainable development. This also largely applies to today's trafficsystem, which needs to change to more sustainable trffic system. Increased active travel is a nescessery for reaching the set goals that exist when it comes to sustainable travel. Increased active travel will lead to more unprotected road users in the trafficsystem, one group of unprotected road users are pedestrians. An increased number of pedestrians in the trafficsystem requires additional efforts to ensure traffic safety for that group. Method: An scoping review is carried out in which police and legislative measures aimed at increasing road safety for pedestrians are evaluated. The purpose of the study is to gain knowledge about what measures the current research proposes to increase traffic safety and to come up with proposals for additional areas where more research is needed. The study builds on two previous literature studies that superficially touched on the subject. Seven scientific articles are taken from these literature studies, a further 13 scientific articles are selected after a literature search. A total of 20 scientific articles that meet the inclusion criteria are included and analyzed. In order to assess whether Swedish authorities implement effective police and legislative measures with the aim of increasing traffic safety for pedestrians, a comparison is made between the measures proposed by the research and the measures that two Swedish authorities, the Swedish Transport Agency and the Swedish Police Agency, present in their documents Aktionsplan för säker vägtrafik 2022–2025 - 250 åtgärder som 33 myndigheter och aktörer avser att vidta för ökad trafiksäkerhet samt Polismyndighetens strategi inom trafiksäkerhetsarbetet. Results: The study shows that targeted police measures aimed at fining individuals who break traffic rules in a certain place during a certain time have a positive effect on pedestrian traffic safety. The focus should be on increasing rule compliance and reducing the number of speed limit violations by motorists, as well as encouraging pedestrians not to walk against red lights. The legislative measures that the scoping review shows have the best effect are lowering the speed limit and car-free zones on stretches of road where many pedestrians are moving. Conclusions: The conclusions that thos scoping review draws are that further research is required in the connection between reduced average speed and the number of traffic accidents which leads to personal injuries to pedestrians, as well as the part of police and legislative measures in different action programs that include several different measures that are implemented together. The police authority is working towards a reduced average speed of motorists through targeted police measures, which is in line with the measures proposed by the existing research in the area. However, there is nothing in the document about targeted police measures against pedestrians in order to increase rule compliance by that group, which is something that the Police Authority is recommended to develop. In the Swedish Transport Agency's action plan for the years 2022-2025, no measures are mentioned to increase pedestrian traffic safety linked to traffic accidents. Only measures to reduce the number of fall injuries are presented. The Swedish Transport Agency is therefore recommended to further develop its action plan and also have it include legislative measures such as reduced speed limits or car-free zones on road sections where many pedestrians move.
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Προηγμένα συστήματα υποβοήθησης οδηγού με μεθόδους υπολογιστικής όρασης / Advanced driver assistance systems with computer vision methods

Σιόγκας, Γιώργος 27 January 2014 (has links)
Τα αυτοκινητιστικά δυστυχήματα αποτελούν μια από τις κυριότερες αιτίες θανάτου παγκοσμίως. Ο αυξανόμενος αριθμός τους οδήγησε στην συνειδητοποίηση ότι η χρήση προηγμένης τεχνολογίας για την κατασκευή ασφαλέστερων οχημάτων είναι απαραίτητη για την μείωση των ατυχημάτων και κατά συνέπεια των θανάτων που οφείλονται σε αυτά. Από τη στιγμή που οι τεχνολογικές εξελίξεις επέτρεψαν την ενσωμάτωση φθηνών, χαμηλής κατανάλωσης συστημάτων με μεγάλη επεξεργαστική ταχύτητα σε οχήματα, κατέστη προφανές ότι περίπλοκες τεχνικές υπολογιστικής όρασης μπορούσαν πλέον να χρησιμοποιηθούν για την υποβοήθηση της οδήγησης. Σε αυτή την κατεύθυνση, η παρούσα διατριβή εστιάζει στην ανάπτυξη καινοτόμων λύσεων για διαφορετικά κομμάτια που εμπλέκονται στα προηγμένα συστήματα υποβοήθησης του οδηγού. Πιο συγκεκριμένα, σε αυτή την διατριβή προτείνονται καινοτόμα υποσυστήματα για την αναγνώριση σημάτων οδικής κυκλοφορίας, την αναγνώριση φωτεινών σηματοδοτών, τον εντοπισμό προπορευόμενου οχήματος και τον εντοπισμό δρόμου. Οι τεχνικές που χρησιμοποιήθηκαν για την ανάπτυξη των προτεινόμενων λύσεων βασίζονται στην χρωματική επεξεργασία εικόνας με έμφαση στην ανεξαρτησία από την φωτεινότητα της σκηνής, στην χρήση πληροφορίας συμμετρίας για τον εντοπισμό χαρακτηριστικών αντικειμένων (όπως σήματα οδικής κυκλοφορίας, φωτεινοί σηματοδότες και οχήματα), στην χώρο-χρονική παρακολούθηση των εντοπισμένων αντικειμένων και στην αυτόματη κατάτμηση εικόνας για τον εντοπισμό δρόμου. Τα προτεινόμενα συστήματα αναπτύχθηκαν με στόχο την ανθεκτικότητα σε αλλαγές της φωτεινότητας ή τις καιρικές συνθήκες, καθώς και στην οδήγηση σε απαιτητικά περιβάλλοντα. Επίσης, έχει δοθεί ιδιαίτερη έμφαση στην προοπτική υλοποίησης συστημάτων πραγματικού χρόνου. Τα αποτελέσματα που παρουσιάζονται σε αυτή την διατριβή αποδεικνύουν την ανωτερότητα των προτεινόμενων μεθόδων έναντι αντίστοιχων της σχετικής βιβλιογραφίας, ειδικά στις περιπτώσεις του εντοπισμού προπορευόμενου οχήματος και του εντοπισμού δρόμου. Ελπίζουμε ότι μέρη της έρευνας αυτής θα εμπνεύσουν νέες προσεγγίσεις για τις μελλοντικές υλοποιήσεις αντίστοιχων συστημάτων. / Traffic accidents are one of the main reasons for the loss of human lives worldwide. Their increasing number has led to the realization that the use of advanced technology for manufacturing safer vehicles is imperative for limiting casualties. Since technological breakthroughs allowed the incorporation of cheap, low consumption systems with high processing speeds in vehicles, it became apparent that complex computer vision techniques could be used to assist drivers in navigating their vehicles. In this direction, this thesis focuses on providing novel solutions for different tasks involved in advanced driver assistance systems. More specifically, this thesis proposes novel sub-systems for traffic sign recognition, traffic light recognition, preceding vehicle detection and road detection. The techniques used for developing the proposed solutions are based on color image processing with a focus on illumination invariance, using symmetry information for man-made objects (like traffic signs, traffic lights and vehicles) detection, spatiotemporal tracking of detected results and automated image segmentation for road detection. The proposed systems were implemented with a goal of robustness to changes of illumination and weather conditions, as well as to diverse driving environments. A special focus on the prospect for real-time implementation has also been given. The results presented in this thesis indicate the superiority of the proposed methods to their counterparts found in relevant literature in both normal and challenging conditions, especially in the cases of preceding vehicle detection and road detection. Hopefully, parts of this research will provide new insights for future developments in the field of intelligent transportation.

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