Thesis (M.S.)--University of Wyoming, 2008. / Title from PDF title page (viewed on Dec. 23, 2009). Includes bibliographical references (p. 125-126).

This paper reviews the effectiveness of vehicle activated signs. Vehicle activated signs are being reportedly used in recent years to display dynamic information to road users on an individual basis in order to give a warning or inform about a specific event. Vehicle activated signs are triggered individually by vehicles when a certain criteria is met. An example of such criteria is to trigger a speed limit sign when the driver exceeds a pre-set threshold speed. The preset threshold is usually set to a constant value which is often equal, or relative, to the speed limit on a particular road segment. This review examines in detail the basis for the configuration of the existing sign types in previous studies and explores the relation between the configuration of the sign and their impact on driver behavior and sign efficiency. Most of previous studies showed that these signs have significant impact on driver behavior, traffic safety and traffic efficiency. In most cases the signs deployed have yielded reductions in mean speeds, in speed variation and in longer headways. However most experiments reported within the area were performed with the signs set to a certain static configuration within applicable conditions. Since some of the aforementioned factors are dynamic in nature, it is felt that the configurations of these signs were thus not carefully considered by previous researchers and there is no clear statement in the previous studies describing the relationship between the trigger value and its consequences under different conditions. Bearing in mind that different designs of vehicle activated signs can give a different impact under certain conditions of road, traffic and weather conditions the current work suggests that variable speed thresholds should be considered instead.

Thesis (M.S.)--University of Central Florida, 2009. / Adviser: Haitham Al-Deek. Includes bibliographical references (p. 173-177).

With perpetual strains on resources, road agencies need to develop network-level decision-making frameworks to ensure optimum resource allocation. This is especially true for incident management services and in particular variable message signs (VMS), which are relatively immature disciplines compared to traditional road engineering. The objective of incident management and VMS is to minimise the safety, efficiency, reliability and environmental impacts of incidents on the operations of the transport system. This may be achieved by informing travellers of the incidents so they can adapt their behaviour in a manner that reduces community impacts, such as lateness and the associated vehicle emissions, unreliability of travel times, as well as secondary accidents due to incidents. Generally, road authorities do carry out needs assessments, but qualitatively in many cases. Therefore, this masters research presents a framework that is systematic, quantitative and relatively easy to implement. In order to prioritise VMS infrastructure deployment, a risk management approach was taken that focuses on minimising the impacts on, and costs to the community. In the framework and case study conducted, safety, efficiency and reliability, and environmental impacts are quantified using an economic risk management approach to determine an overall risk score. This score can be used to rank road sections within the network, indicating the roads with the highest risk of incident network impacts and therefore the roads with the highest need for intervention. A cost-effectiveness based risk-reduction ranking can then be determined for each incident management treatment type, comparing the net risk with treatment to that without treatment, and dividing by the net present value of deployment. The two types of ranking, pure risk and cost-effectiveness based risk reduction, will help to minimise the network impacts on the community and optimise resource allocation.

This thesis presents the findings of a comprehensive research study conducted for the Utah Department of Transportation (UDOT) to evaluate the effectiveness of commonly deployed Intelligent Transportation System (ITS) treatments in Utah, with a focus on Variable Message Signs (VMS), traffic cameras, and Road Weather Information System(s) (RWIS) sites. The study aimed to determine the impact of these ITS treatments on mobility and safety for Utah's unique road conditions and configurations. Three primary analyses were performed: a diversion rates analysis to assess the effectiveness of VMS on Utah freeways during incidents; a weather analysis to evaluate the effectiveness of VMS messages on driver speeds in Utah canyons during winter weather; and an ITS attitudes survey to gauge the usage of, attitudes towards, and potential improvements to UDOT's current ITS deployment. The findings of the diversion rates analysis indicate that the activation of VMS messages increase diversion rates by 18 percent and from the weather analysis, a negligible increase of speeds by 0.2 mph was observed. Survey results were largely positive with a high level of ITS usage and benefits reported by UDOT employees. Concerns of general device wear and maintenance were documented. The report provides detailed methodologies, results, conclusions, and recommendations derived from this research, offering valuable insights to guide UDOT's ITS deployment strategies.

Este trabalho propõe um método para avaliação das condições de fluidez do tráfego em vias arteriais da cidade de Porto Alegre sob a ótica de seus usuários, de modo a subsidiar a apresentação destas informações através dos painéis de mensagem variável (PMV). Para atingir o objetivo proposto, foram levantados: (i) estado-da-arte e da prática sobre a utilização de PMV; (ii) características das vias arteriais da cidade; (iii) imagens de vídeo e dados de tráfego destas vias; (iv) a percepção dos usuários sobre a fluidez do tráfego. O levantamento do estado-da-arte e da prática permitiu conhecer quais as características das mensagens, sejam elas do padrão construtivo ou do conteúdo, podem influenciar no comportamento do usuário. O estudo do sistema viário permitiu a escolha de vias de grande importância para a mobilidade da população para a aplicação do estudo. Os dados de tráfego e as imagens de vídeo destas vias foram utilizados na elaboração de cenários que buscaram representar situações de tráfego encontradas nos grandes centros urbanos. Os cenários foram avaliados por usuários das vias em questão. A partir dos resultados da pesquisa qualitativa, foram realizadas modelagens e obtidas equações que relacionam a percepção de fluidez do tráfego por parte dos usuários com a velocidade média do trecho. Os resultados indicaram que: (i) a velocidade média tem grande influência sobre a percepção de fluidez por parte dos motoristas; (ii) a avaliação sobre a fluidez do tráfego piora significativamente com a redução da velocidade média; (iii) os modelos para vias em estudo tem comportamentos semelhantes. Além disso, este trabalho propõe uma escala de qualificação da fluidez do tráfego levando em consideração a percepção dos usuários, utilizando a velocidade média com indicador de desempenho. / This paper proposes a method for analyzing the conditions of traffic flow on arterial roads of the Porto Alegre city from the perspective of its users in order to submit this information by variable message signs (VMS). To reach that goal has been raised: (i) state of the art and practice on the use of VMS; (ii) characteristics of the arterial roads of the city; (iii) video images and data traffic from these roads; ( iv) the perception of users about the traffic flow. The lifting of the state of the art and practice which helped identify the characteristics of messages, whether constructive or the standard of content, can influence the behavior of the user. The study of the road system allowed the choice of channels of great importance to the mobility of the population to implement the study. Traffic data and video images of these routes were used in the preparation of scenarios that sought to represent traffic situations found in large urban centers. The scenarios were evaluated by users of the roads in question. From the results of qualitative research, modeling was performed and obtained equations that relate the perception of traffic flow for users with average speed of the stretch. The results indicated that: (i) the average speed has great influence on the perception of fluidity by the drivers, (ii) the assessment of traffic flow worsened significantly with the reduction of average speed, (iii) models for railway under study have similar behaviors. In addition, this paper proposes scales qualification of traffic flow from the perspective of users, using the average speed with performance indicator.

Este trabalho propõe um método para avaliação das condições de fluidez do tráfego em vias arteriais da cidade de Porto Alegre sob a ótica de seus usuários, de modo a subsidiar a apresentação destas informações através dos painéis de mensagem variável (PMV). Para atingir o objetivo proposto, foram levantados: (i) estado-da-arte e da prática sobre a utilização de PMV; (ii) características das vias arteriais da cidade; (iii) imagens de vídeo e dados de tráfego destas vias; (iv) a percepção dos usuários sobre a fluidez do tráfego. O levantamento do estado-da-arte e da prática permitiu conhecer quais as características das mensagens, sejam elas do padrão construtivo ou do conteúdo, podem influenciar no comportamento do usuário. O estudo do sistema viário permitiu a escolha de vias de grande importância para a mobilidade da população para a aplicação do estudo. Os dados de tráfego e as imagens de vídeo destas vias foram utilizados na elaboração de cenários que buscaram representar situações de tráfego encontradas nos grandes centros urbanos. Os cenários foram avaliados por usuários das vias em questão. A partir dos resultados da pesquisa qualitativa, foram realizadas modelagens e obtidas equações que relacionam a percepção de fluidez do tráfego por parte dos usuários com a velocidade média do trecho. Os resultados indicaram que: (i) a velocidade média tem grande influência sobre a percepção de fluidez por parte dos motoristas; (ii) a avaliação sobre a fluidez do tráfego piora significativamente com a redução da velocidade média; (iii) os modelos para vias em estudo tem comportamentos semelhantes. Além disso, este trabalho propõe uma escala de qualificação da fluidez do tráfego levando em consideração a percepção dos usuários, utilizando a velocidade média com indicador de desempenho. / This paper proposes a method for analyzing the conditions of traffic flow on arterial roads of the Porto Alegre city from the perspective of its users in order to submit this information by variable message signs (VMS). To reach that goal has been raised: (i) state of the art and practice on the use of VMS; (ii) characteristics of the arterial roads of the city; (iii) video images and data traffic from these roads; ( iv) the perception of users about the traffic flow. The lifting of the state of the art and practice which helped identify the characteristics of messages, whether constructive or the standard of content, can influence the behavior of the user. The study of the road system allowed the choice of channels of great importance to the mobility of the population to implement the study. Traffic data and video images of these routes were used in the preparation of scenarios that sought to represent traffic situations found in large urban centers. The scenarios were evaluated by users of the roads in question. From the results of qualitative research, modeling was performed and obtained equations that relate the perception of traffic flow for users with average speed of the stretch. The results indicated that: (i) the average speed has great influence on the perception of fluidity by the drivers, (ii) the assessment of traffic flow worsened significantly with the reduction of average speed, (iii) models for railway under study have similar behaviors. In addition, this paper proposes scales qualification of traffic flow from the perspective of users, using the average speed with performance indicator.

Este trabalho propõe um método para avaliação das condições de fluidez do tráfego em vias arteriais da cidade de Porto Alegre sob a ótica de seus usuários, de modo a subsidiar a apresentação destas informações através dos painéis de mensagem variável (PMV). Para atingir o objetivo proposto, foram levantados: (i) estado-da-arte e da prática sobre a utilização de PMV; (ii) características das vias arteriais da cidade; (iii) imagens de vídeo e dados de tráfego destas vias; (iv) a percepção dos usuários sobre a fluidez do tráfego. O levantamento do estado-da-arte e da prática permitiu conhecer quais as características das mensagens, sejam elas do padrão construtivo ou do conteúdo, podem influenciar no comportamento do usuário. O estudo do sistema viário permitiu a escolha de vias de grande importância para a mobilidade da população para a aplicação do estudo. Os dados de tráfego e as imagens de vídeo destas vias foram utilizados na elaboração de cenários que buscaram representar situações de tráfego encontradas nos grandes centros urbanos. Os cenários foram avaliados por usuários das vias em questão. A partir dos resultados da pesquisa qualitativa, foram realizadas modelagens e obtidas equações que relacionam a percepção de fluidez do tráfego por parte dos usuários com a velocidade média do trecho. Os resultados indicaram que: (i) a velocidade média tem grande influência sobre a percepção de fluidez por parte dos motoristas; (ii) a avaliação sobre a fluidez do tráfego piora significativamente com a redução da velocidade média; (iii) os modelos para vias em estudo tem comportamentos semelhantes. Além disso, este trabalho propõe uma escala de qualificação da fluidez do tráfego levando em consideração a percepção dos usuários, utilizando a velocidade média com indicador de desempenho. / This paper proposes a method for analyzing the conditions of traffic flow on arterial roads of the Porto Alegre city from the perspective of its users in order to submit this information by variable message signs (VMS). To reach that goal has been raised: (i) state of the art and practice on the use of VMS; (ii) characteristics of the arterial roads of the city; (iii) video images and data traffic from these roads; ( iv) the perception of users about the traffic flow. The lifting of the state of the art and practice which helped identify the characteristics of messages, whether constructive or the standard of content, can influence the behavior of the user. The study of the road system allowed the choice of channels of great importance to the mobility of the population to implement the study. Traffic data and video images of these routes were used in the preparation of scenarios that sought to represent traffic situations found in large urban centers. The scenarios were evaluated by users of the roads in question. From the results of qualitative research, modeling was performed and obtained equations that relate the perception of traffic flow for users with average speed of the stretch. The results indicated that: (i) the average speed has great influence on the perception of fluidity by the drivers, (ii) the assessment of traffic flow worsened significantly with the reduction of average speed, (iii) models for railway under study have similar behaviors. In addition, this paper proposes scales qualification of traffic flow from the perspective of users, using the average speed with performance indicator.

Changeable Message Signs (CMS) are commonly utilized by transportation agencies to inform motorists of traffic, roadway, and environmental conditions. They may be used to provide information, such as delay and alternate route guidance, in the event of an incident, construction or a roadway closure. The effectiveness of CMS in managing freeway traffic, however, is a function of many factors including the number of CMS installations, the location of CMS, the messages displayed, varied traffic network characteristics, and drivers' response to incident conditions and CMS information. The objective of this thesis is to develop a CMS location planning model that can be used by transportation agencies to develop a CMS location plan that could achieve the largest long-term benefit to the system. This research is mainly motivated by the lack of systematic, robust and practical methods for locating CMS. State-of-practice methods rely mostly on the practitioner's experience and judgement. Other methods fail to incorporate reasonable driver behaviour models, consider time-varying demand, allow for computational efficiency on large networks, or consider the spatial variation of incidents on a traffic network. A new CMS location optimization model has been developed that is unique in both model realism and computational efficiency. The model incorporates several components to estimate incident delay, predict driver response, estimate network-wide benefit, and choose those CMS locations that would provide the most benefit. Deterministic queuing methods are used in conjunction with historic incident characteristics to approximate the delay impact of an incident with and without CMS. A discrete choice model is used to predict the rate at which drivers would switch from the incident route to a less congested alternative under CMS information. A network traffic assignment model is then incorporated in an attempt to estimate the resulting traffic induced by incidents. Genetic algorithms are utilized as an optimization technique to choose a set of CMS that would provide the most benefit. An extensive computational analysis was performed on both a hypothetical network and a segment of Highway 401 through Toronto. A sensitivity analysis was performed to test the model's response to parameter and data estimation errors. The model was found to be most sensitive to the diversion model parameters. The model produced reasonable results with locations selected upstream of major freeway interchange diversion points. Considering the additional components included in the proposed model, and its ability to consider more location schemes, the proposed model may be considered superior to previous CMS location models.

Changeable Message Signs (CMS) are commonly utilized by transportation agencies to inform motorists of traffic, roadway, and environmental conditions. They may be used to provide information, such as delay and alternate route guidance, in the event of an incident, construction or a roadway closure. The effectiveness of CMS in managing freeway traffic, however, is a function of many factors including the number of CMS installations, the location of CMS, the messages displayed, varied traffic network characteristics, and drivers' response to incident conditions and CMS information. The objective of this thesis is to develop a CMS location planning model that can be used by transportation agencies to develop a CMS location plan that could achieve the largest long-term benefit to the system. This research is mainly motivated by the lack of systematic, robust and practical methods for locating CMS. State-of-practice methods rely mostly on the practitioner's experience and judgement. Other methods fail to incorporate reasonable driver behaviour models, consider time-varying demand, allow for computational efficiency on large networks, or consider the spatial variation of incidents on a traffic network. A new CMS location optimization model has been developed that is unique in both model realism and computational efficiency. The model incorporates several components to estimate incident delay, predict driver response, estimate network-wide benefit, and choose those CMS locations that would provide the most benefit. Deterministic queuing methods are used in conjunction with historic incident characteristics to approximate the delay impact of an incident with and without CMS. A discrete choice model is used to predict the rate at which drivers would switch from the incident route to a less congested alternative under CMS information. A network traffic assignment model is then incorporated in an attempt to estimate the resulting traffic induced by incidents. Genetic algorithms are utilized as an optimization technique to choose a set of CMS that would provide the most benefit. An extensive computational analysis was performed on both a hypothetical network and a segment of Highway 401 through Toronto. A sensitivity analysis was performed to test the model's response to parameter and data estimation errors. The model was found to be most sensitive to the diversion model parameters. The model produced reasonable results with locations selected upstream of major freeway interchange diversion points. Considering the additional components included in the proposed model, and its ability to consider more location schemes, the proposed model may be considered superior to previous CMS location models.