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Percepção dos usuários sobre a qualidade de serviço em rodovias / Users\' perception of quality of service at highwaysPaiva, Artur Piatti Oiticica de 11 August 2015 (has links)
Com o intuito de fornecer subsídios para adaptar o HCM ao cenário brasileiro, propõe-se um método que se baseia na percepção dos usuários sobre a qualidade de serviço em rodovias, para estimar os limites de densidade que delimitam os níveis de serviço. A justificativa é que o conceito de nível de serviço considera a qualidade de serviço com base na percepção dos usuários, mas os limites entre os níveis de serviço em rodovias definidos no HCM não considera a opinião dos usuários. Esse método baseia-se num questionário online para coletar as informações necessárias para estimar os limites entre os níveis de serviço por uma análise de regressão logística. No método proposto, a percepção dos usuários sobre a qualidade de serviço é medida através de uma escala contínua e as condições operacionais são mostradas através de vídeos obtidos com um simulador microscópico de tráfego. Um experimento piloto foi realizado para testar o questionário e o método de análise propostos. As variáveis operacionais utilizadas no experimento piloto foram percentual de veículos pesados, velocidade média e concentração veicular. Os resultados desse experimento piloto foram usados para refinar o questionário e mostraram que, dentre as consideradas, a densidade foi a medida operacional que mais influiu na qualidade de serviço percebida pelos respondentes. Por meio do experimento piloto, foi possível estimar o tamanho do questionário e a duração dos vídeos. O método proposto pode ser aplicado para obter os limites entre os níveis de serviço com base na percepção do usuário, no Brasil ou em qualquer outro país, uma vez que um simulador microscópico devidamente calibrado para refletir as condições operacionais locais esteja disponível. / This thesis proposes a method to estimate thresholds for levels of service based on the users\' perception of the quality of service on highways. Whereas the level of service concept includes the users\' perception of the quality of service among the aspects that should be taken into consideration, the level of service criteria used in the highway chapters of the HCM were defined without taking into acc ount the users\' opinion. The proposed approach uses an online questionnaire to obtain the data needed to estimate the thresholds between levels of service, which are then calculated using logistic regression. In the proposed method, the users\' perception of the quality of service is measur ed using a continuous scale and the operating conditions are shown by means of short videos created using microscopic traffic simulation of predetermined scenarios on a virtual highway. By using simulation to create scenarios, it is possible to control all operational variables, covering all cond itions from very low flow to capacity, and, at the same time, to generate a video from the driver\'s point of view. A pilot experiment was used to validate the questionnaire and the method adopted to estimate level of service thresholds. The operational variables used in this pilot experiment included truck percent, average travel speed and density. The results of the pilot experiment were used to refine the questionnaire and have shown that density is the operational variable that has the greatest influence on the users\' perception of the quality of service. The pilot experiment results also defined the number and the length of the videos to be shown to respondents. Despite its creation to support the adaptation of the HCM to Brazil, the proposed method could be applied to any other location, if a microscopic traffic simulator calibrated to represen ttraffic flow on local highways is available.
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Percepção dos usuários sobre a qualidade de serviço em rodovias / Users\' perception of quality of service at highwaysArtur Piatti Oiticica de Paiva 11 August 2015 (has links)
Com o intuito de fornecer subsídios para adaptar o HCM ao cenário brasileiro, propõe-se um método que se baseia na percepção dos usuários sobre a qualidade de serviço em rodovias, para estimar os limites de densidade que delimitam os níveis de serviço. A justificativa é que o conceito de nível de serviço considera a qualidade de serviço com base na percepção dos usuários, mas os limites entre os níveis de serviço em rodovias definidos no HCM não considera a opinião dos usuários. Esse método baseia-se num questionário online para coletar as informações necessárias para estimar os limites entre os níveis de serviço por uma análise de regressão logística. No método proposto, a percepção dos usuários sobre a qualidade de serviço é medida através de uma escala contínua e as condições operacionais são mostradas através de vídeos obtidos com um simulador microscópico de tráfego. Um experimento piloto foi realizado para testar o questionário e o método de análise propostos. As variáveis operacionais utilizadas no experimento piloto foram percentual de veículos pesados, velocidade média e concentração veicular. Os resultados desse experimento piloto foram usados para refinar o questionário e mostraram que, dentre as consideradas, a densidade foi a medida operacional que mais influiu na qualidade de serviço percebida pelos respondentes. Por meio do experimento piloto, foi possível estimar o tamanho do questionário e a duração dos vídeos. O método proposto pode ser aplicado para obter os limites entre os níveis de serviço com base na percepção do usuário, no Brasil ou em qualquer outro país, uma vez que um simulador microscópico devidamente calibrado para refletir as condições operacionais locais esteja disponível. / This thesis proposes a method to estimate thresholds for levels of service based on the users\' perception of the quality of service on highways. Whereas the level of service concept includes the users\' perception of the quality of service among the aspects that should be taken into consideration, the level of service criteria used in the highway chapters of the HCM were defined without taking into acc ount the users\' opinion. The proposed approach uses an online questionnaire to obtain the data needed to estimate the thresholds between levels of service, which are then calculated using logistic regression. In the proposed method, the users\' perception of the quality of service is measur ed using a continuous scale and the operating conditions are shown by means of short videos created using microscopic traffic simulation of predetermined scenarios on a virtual highway. By using simulation to create scenarios, it is possible to control all operational variables, covering all cond itions from very low flow to capacity, and, at the same time, to generate a video from the driver\'s point of view. A pilot experiment was used to validate the questionnaire and the method adopted to estimate level of service thresholds. The operational variables used in this pilot experiment included truck percent, average travel speed and density. The results of the pilot experiment were used to refine the questionnaire and have shown that density is the operational variable that has the greatest influence on the users\' perception of the quality of service. The pilot experiment results also defined the number and the length of the videos to be shown to respondents. Despite its creation to support the adaptation of the HCM to Brazil, the proposed method could be applied to any other location, if a microscopic traffic simulator calibrated to represen ttraffic flow on local highways is available.
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Level-of-service And Traffic Safety Relationship: An Exploratory Analysis Of Signalized Intersections And Multiland High-speed Arterial CorridorsAlmonte-Valdivia, Ana 01 January 2009 (has links)
Since its inception in 1965, the Level-of-Service (LOS) has proved to be an important and practical "quality of service" indicator for transportation facilities around the world, widely used in the transportation and planning fields. The LOS rates these facilities' traffic operating conditions through the following delay-based indicators (ordered from best to worst conditions): A, B, C, D, E and F. This LOS rating has its foundation on quantifiable measures of effectiveness (MOEs) and on road users' perceptions; altogether, these measures define a LOS based on acceptable traffic operating conditions for the road user, implying that traffic safety is inherent to this definition. However, since 1994 safety has been excluded from the LOS definition since it cannot be quantified nor explicitly defined. The latter has been the motivation for research based on the LOS-Safety relationship, conducted at the University of Central Florida (UCF). Using data from two of the most studied transportation facility types within the field of traffic safety, signalized intersections and multilane high-speed arterial corridors, the research conducted has the following main objectives: to incorporate the LOS as a parameter in several traffic safety models, to extend the methodology adopted in previous studies to the subject matter, and to provide a platform for future transportation-related research on the LOS-Safety relationship. A meticulous data collection and preparation process was performed for the two LOS-Safety studies comprising this research. Apart from signalized intersections' and multilane-high speed arterial corridors' data, the other required types of information corresponded to crashes and road features, both obtained from FDOT's respective databases. In addition, the Highway Capacity Software (HCS) and the ArcGIS software package were extensively used for the data preparation. The result was a representative and robust dataset for each LOS-Safety study, to be later tested and analyzed with appropriate statistical methods. Regarding the LOS-Safety study for signalized intersections, two statistical techniques were used. The Generalized Estimating Equations (GEEs), the first technique, was used for the analyses considering all periods of a regular weekday (i.e. Monday through Friday): Early Morning, A.M. Peak, Midday, P.M. Peak and Late Evening; the second technique considered was the Negative Binomial, which was used for performing an individual analysis per period of the day. On the other hand, the LOS-Safety study for multilane high-speed arterial corridors made exclusive use of the Negative Binomial technique. An appropriate variable selection process was required for the respective model building and calibration procedures; the resulting models were built upon the six following response variables: total crashes, severe crashes, as well as rear-end, sideswipe, head-on and angle plus left-turn crashes. The final results proved to be meaningful for the understanding of traffic congestion effects on road safety, and on how they could be useful within the transportation planning scope. Overall, it was found that the risk for crash occurrence at signalized intersections and multilane high-speed arterial corridors is quite high between stable and unacceptable operating conditions; it was also found that this risk increases as it becomes later in the day. Among the significant factors within the signalized intersection-related models were LOS for the intersection as a whole, cycle length, lighting conditions, land use, traffic volume (major and minor roads), left-turn traffic volume (major road only), posted speed limit (major and minor roads), total number of through lanes (major and minor roads), overall total and total number of left-turn lanes (major road only), as well as county and period of the day (dummy variables). For multilane-high speed arterial corridors, the final models included LOS for the road section, average daily traffic (ADT), total number of through lanes in a single direction, total length of the road section, pavement surface type, as well as median and inside shoulder widths. A summary of the overall results per study, model implications and each LOS indicator is presented. Some of the final recommendations are to develop models for other crash types, to perform a LOS-Safety analysis at the approach-level for signalized intersections, as well as one that incorporates intersections within the arterial corridors' framework.
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Analysis of Automated Vehicle Location Data from Public Transport Systems to Determine Level of ServiceEriksson, Charlotte, Jansson, Olivia January 2019 (has links)
Many cities suffer from problems with high traffic flows in the city centers which leads to a desire to get more people to choose public transport over cars. For many car drivers, the main reason to take the car is the convenience and time efficiency; the price is often of less importance. The public transport providers should, therefore, strive to improve their Level of Service (LOS). A general process that can be used by public transport providers or other stakeholders to evaluate the LOS in a public transport system based on Automated Vehicle Location (AVL) data is developed and presented in this thesis.The process values the quality and suitability of the AVL data, propose which KPIs to use and how to use the results to find possible improvements. Four different types of erroneous data were discovered: outliers in position, outliers in speed, outliers in travel time and general errors. KPIs are developed in three main areas: on-time performance, travel time distribution and speed, where each KPI is divided into several sub-areas.
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