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The use of public participation in the design of effective internet-based advanced traveler information systemsRoell, Maria 14 November 2012 (has links)
This thesis examines three methods of public participation and their potential application to the design of internet-based Advanced Traveler Information Systems (ATISs). ATISs have the ability to reduce congestion by providing their users with real-time traffic information that can affect their travel decisions to avoid areas of high traffic. This study first uses a website evaluation method to determine a baseline of ATIS website quality. It then uses three forms of public participation, a survey, a future's workshop, and a feedback website to determine user preferences for Georgia's traveler information website, NaviGAtor. The results of the participation are then analyzed for their strengths and weaknesses and their applicability to ATIS development. The study concludes that the feedback website is the most applicable form of participation for ATIS design, followed by surveys that should be used periodically, and future's workshops that should be used rarely.
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Framtidens reseplanerare : Hur man designar en mobil, dynamisk & multimodal reseplanerareRudqwist, Lucas, Magnusson, Max January 2016 (has links)
Detta arbete tar en titt in i framtidens möjligheter för mobila, dynamiska och multimodala reseplanerare. Detta genom att ställa frågorna: Hur kan en multimodal reseplaneringstjänst med data och information från befintliga resurser se ut och fungera i Stockholms län? Hur designar man en väl fungerande mobil resetjänst som förmedlar dynamiska multimodala transportvägar med god användbarhet? Vilken information och vilka system finns tillgängliga öppet och vilken information måste framtidens reseplanerare själv skapa? Genom skapandet av prototyper och användartester i tre steg knyter vi samman tidigare genomförd forskning med den faktiska data och information som finns tillgängligt öppen i Stockholms län. Detta för att visa hur framtidens reseplanerare kan komma att se ut och fungera. Den slutgiltiga designen visar hur morgondagens reseplanerare sömlöst och enkelt kommer kunna guida användaren att resa multimodalt genom att koppla ihop flera olika trafikinformationssystem, elektroniska betalsystem och smarta mobiltelefoners inbyggda resurser (så som t.ex. dess GPS/A-GPS). Som komplement till designförslaget presenterar vi de tre komponenterna som, enligt vår studie, är mest kritiska för att lyckas med framtidens reseplanerare. / This thesis takes a look at the future of mobile, dynamic and multimodal travel planners by asking the questions: How can a multimodal travel planner with data and information from existing resources be designed and function in Stockholm County? How do you design a well-functioning mobile travel planner that delivers dynamic multimodal travel with high usability? What information and what systems are publicly accessible today and what information must the future travel planner create by itself? By creating prototypes and by usability testing in three steps we tie previous research together with available data and information publicly accessible in Stockholm County. The goal of this is to show how a future travel planner can look and work. The final design of the travel planner of tomorrow shows how seamless and simple it will be to guide the user to multimodal travel. All this by connecting traffic information systems, electronic payment methods and smartphones built in resources (e.g. its GPS/A-GPS). As a complement to the design we present three key components that, according to this study, are the most critical to succeed with a future travel planner.
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Evaluation of Travel Time Estimates Derived From Automatic Vehicle Identification Tags in San Antonio, TXRiley, John D. 17 July 1999 (has links)
The purpose of this research is to examine several aspects of the San Antonio automated vehicle identification (AVI) system, including the reliability and accuracy of the AVI system, travel tag level of market penetration (LMP) trends, and a comparison of aggregated travel time values with probe vehicle travel time values. This thesis serves as a first step toward the modeling of AVI systems in which the effects of travel tag LMP, AVI reader density and AVI reader location are analyzed.
GPS units were first tested as a suitable benchmark for validating AVI reliability and accuracy. A two-part system reliability study was then performed, consisting of overall system reliability and a controlled evaluation of selected AVI reader sites. The accuracy of AVI travel times was also assessed. A LMP analysis was then performed to serve as a reference parameter for the aggregate travel time study. Lastly, the level of aggregation analysis attempted to quantify differences between the individual test vehicle travel times and aggregated travel times of all observed, tag-equipped vehicles.
Overall system reliability was found to be greater than 90%. The controlled reliability study showed that freeway AVI readers slightly outperformed arterial readers for correct tag capture, while total tag capture exceeded the system design parameter of 80%. Tag capture rates were found to be independent of test vehicle speed. The LMP of travel tags at a selected reader site was found to be approximately 0.5% from the morning through the evening peak. Lastly, 5-minute travel time aggregations provided a better estimate of individual test vehicle travel times than 2-minute or 15-minute aggregations. / Master of Science
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Effects of In-Vehicle Information Systems (IVIS) Tasks on the Information Processing Demands of a Commercial Vehicle Operations (CVO) DriverBlanco, Myra 31 December 1999 (has links)
This study was performed with two main goals in mind. The first goal was to understand and predict "red-lines" and "yellow-lines" in terms of what the CVO driver can process without hindering the primary task of driving. The second goal was to collect conventional secondary task data for CVO driving performance. An on-the-road experiment was performed with the help of 12 truck drivers. Type of task, presentation format, information density, and age were the independent variables used in the experiment. The 22 dependent measures collected were grouped into the following categories: eye glance measures, longitudinal driving performance, lateral driving performance, secondary task performance, and subjective assessment. The findings of this study strongly suggest that paragraphs should not be used under any circumstance to present information to the driver while the vehicle is in motion. On the other hand, the Graphics with Icons represent the most appropriate format in which driving instructions and information should be presented for IVIS/CVO tasks. In order to avoid a high visual attention demand to the driver due to a secondary task, only simple search tasks with the most important information shall be presented. Although the suggested format, type of task, and information density represent a higher visual attention demand than a conventional secondary task, these characteristics seem to bind a task with a moderate attentional demand. Other combinations of format, type of task, and information density will cause an increase in the driver's attentional demand that will consequently deteriorate their driving performance causing unsafe driving situations. / Master of Science
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Evaluating Travelers Experience with Highway Advisory Radio (HAR) And Citizens Band Radio Advisory System (CBRAS) On Florida's Turnpike Enterprise Toll Roadways And Florida Interstate HighwaysMuhaisen, Nabil 01 January 2015 (has links)
The goal of this thesis is to evaluate travelers' experience with Highway Advisory Radio (HAR) and Citizens' Band Radio Advisory System (CBRAS) technologies on both Florida Interstate Highway system (FIH) and the Florida Turnpike Enterprise (FTE) toll roads. To achieve this goal, two different survey tools were used. The first tool is a random digit dialing phone survey known as CATI (Computer-Assisted Telephone Interviewing). The second tool is a field survey that intercepts travelers at the Florida Turnpike Enterprise (FTE) service plazas and the Florida Interstate Highway (FIH) rest areas. HAR and CBRAS are traditional components of the Advanced Traveler Information Systems (ATIS). This thesis pays special attention to the effectiveness of HAR and CBRAS in improving travelers' experience. Feedback to analyze these two technologies was collected via a telephonic survey and a field survey. Two different field surveys (one for HAR and one for CBRAS) were designed and implemented to obtain feedback on these technologies. The field survey for CBRAS is unique and has never been done before for this purpose. A sample size of 1000 HAR surveys was collected through the CATI phone survey. Field surveys were collected at five locations across the state, including central, southeast, and southwest regions of Florida. The HAR field survey sample size was 1610 and the CBRAS field survey sample size was 613. All field surveys were conducted by UCF students at each of the five locations, over a 13-week data collection period. The HAR messages were designed to alert drivers of any adverse roadway traffic or weather conditions. The CBRAS is limited to truck drivers with the closed system radio pre-installed in their vehicles. However, truck drivers were also asked some questions on HAR if they do not use CBRAS. Basic statistical analysis was used to determine a number of performance indicators which include system's use and awareness, usability of provided information, route diversion, and travelers' demographics. In addition, the two HAR phone and field samples were combined together and examined using a decision tree model. Target questions were selected from the survey to build the tree network. The tree model aimed at identifying trends between categorical differences of travelers with respect to specific questions. Understanding travelers' satisfaction with HAR is critical to knowing its benefits. The ending results indicated that both basic statistical analysis and the decision tree model are in agreement. A comparison between HAR phone and field surveys indicates the following. Travelers interviewed for the HAR field survey were more aware of the HAR than travelers surveyed by phone. A small portion of the surveyed samples used HAR (22% and this was consistent between the phone and the field surveys). Also, 80% or more were satisfied with HAR for both phone and field samples and the majority (85% or more) supported its continuation as an indication of willingness to use it in the future, especially in emergency conditions. In terms of the types of messages they want to hear from HAR, traffic congestion was the most common. Dynamic Message Signs (DMS) were the most preferred source of travel information and were the alternative for HAR, if HAR gets terminated. This was followed by smartphone applications which received twice as much support from field surveyed travelers (28%) when compared to phone surveyed travelers (15%). The CATI Phone Survey was biased towards elderly people (60% of the sample) and mainly females (58%) that use the FTE roadway system. Users satisfied with the system are those who only use these roadways once per week or less. The survey ultimately shows that travelers rely on modern modes of obtaining traffic information than traditional ones, such as HAR. DMS, and smart phone applications are leading communication tools among all type of travelers. The HAR field survey was less biased with respect to age and gender distribution (56% were under 50 and 62% were males). Both surveys indicate that the sample is well educated (about 60% have an associate degree or higher). CBRAS serves a small segment of commercial truck drivers (only 12% out of 613 used CBRAS). However, this small segment used it heavily (84% used it sometimes, often, or always). And 92% of CBRAS users were satisfied or strongly satisfied with it. CBRAS was used mostly for route divergence, with 72% of the drivers relying on it for this purpose. Truck drivers who never used CBRAS (88% of the sample) were asked questions about HAR. Only 27% of them used HAR and 57% of these used it sometimes, often, or always with 72% of the truck users being satisfied with HAR compared to the 92% satisfied with CBRAS. The most common complaint about HAR by truck drivers was that it is not easy to access or understand. Based on responses of truck drivers for both HAR and CBRAS field surveys above, it seems that GPS navigation was the most preferred source of travel information (28%). In addition to the basic statistics, a decision tree model, using SAS Enterprise Miner was performed. The statistical analysis results indicated satisfaction of travelers. The decision tree model was used to predict and profile responses to all answered questions that each survey shared. Training data was included in the model and the model was able to leverage the questions. Results of the decision tree model predicted high user satisfaction rates. Analyses of the three implemented surveys show that HAR and CBRAS technologies are not used by a large proportion of travelers, but their users are typically satisfied with these technologies. A small portion of the surveyed sample of truck drivers uses CBRAS but they use it heavily and were very satisfied with it. The travelers' satisfaction level with HAR was high. The HAR and CBRAS systems are in the middle of a heated competition lead by digital communication, it may be a sign of the time to create HAR/CBRAS smart phone applications for the longevity of these traditional technologies.
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A stepwise approach towards achieving a multimodal platform within the context of the CoCT’s land transport networksStruwig, Claudia Bernadine 03 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The importance of transport should not be underestimated. Transport progresses a person’s quality of life: it connects people to one another and provides access to work, services and recreational opportunities. However, post-apartheid South Africa is unfortunately still faced with a legacy of segregation. While the less-privileged, who mostly live at the fringe of Central Business Districts (CBDs), are captive users of public transport, the private vehicle trend, under the privileged, is becoming more evident.
This research project thus proposes that a balanced and integrated sustainable transport system be promoted. That is, one that will aid South Africa in growing and improving its general socio-economical status by providing all its citizens with (equal) access to a balanced transport network. It is believed that, if a multimodal system is promoted, the deficiencies of the current heterogeneous non-integrated systems may be overcome. Therefore, if South Africa’s transport network is augmented with a multimodal platform, the nation will be able to move its citizens effectively and efficiently, without jeopardising the economy, social matters and the environment, today and in the future. Moreover, South Africa will also have the necessary stimulus to utilise the already available resources at its disposal by working together as ‘one’.
This research project thus stipulates a (generic) sequential approach needed in achieving an integrated (sustainable) public transport system. The goal of this research project is to create awareness of the benefits that may arise from, and the implementation steps required in obtaining, such a multimodal platform. The focus area for researching the proposition made herein is the City of Cape Town’s (CoCT’s) land transport networks. The City has a management facility, with resultant transport data repository, known as the Transport Management Centre (TMC). This TMC is regarded as one of the finest state of the art facilities in the world and the features thereof offer a sufficient base and point of departure for the promotion of a multimodal transport system.
By conducting research in this field, the following portraying aspects, needed for the realisation of the proposition made herein, were found. Firstly, in order to obtain an integrated sustainable transport system, the appropriate Intelligent Transport Systems (ITS) need to be integrated. It is believed that, if an intelligent transport scheme, grounded on ITS applications, is advocated, the City will be in the position to more effectively monitor what is going on, to more accurately predict what might happen in the future, and to manage its transport system proactively on an area-wide basis. Secondly, in order to meet the integration requirements imposed by multimodal transport, a centralised database needs to be created. With such a database in place, information sharing across all modes of private- and public land transport, and thus also between the investors or the operators, will be possible. An example of such a database was developed in Microsoft Access and the modes considered therein are: MyCiti, Metrorail and Golden Arrow Bus Service (GABS). The data stored in this database is historic, but the incorporation of real time information was also catered for.
Thirdly, it is believed that the success of the City’s transport system, and the development of a multimodal system, is dependent on the provision of an efficient Advanced Traveller Information System (ATIS). The idea is to promote multimodal transport as a convenient transit option by providing travellers with information on journey planning that aims to counteract their reluctance to change. In order to develop such a multimodal Journey Planner (JP), the unimodal networks considered herein were combined into a supernetwork on which Dijkstra’s Shortest Path Algorithm was applied. This algorithm was programmed in Microsoft Excel’s Visual Basic for Applications (VBA) and it incorporates the following user criteria: the origin, the destination, the user’s mode preference, and the user’s optimisation preference of either time or distance.
In conclusion, it can be argued that, with information becoming such a vital commodity in everyday life, the catering for informed travellers are the key to successful future transport services. If travellers are informed about the transport networks’ performance, a positive attitude is fostered. Moreover, by providing travellers with information on journey planning, their feelings of uncertainty and fear of the unknown, that are present in (especially) public transport services, may be neutralised. This information will give the public carte blanche to make decisions that give them the perception of having more ‘control over their lives’. Therefore, if a multimodal JP that can be accessed from one portal is created, people’s inclination to acquire more information will be met. And as a result, traversing in an integrated manner may become the norm. / AFRIKAANSE OPSOMMING: Die belangrikheid van vervoer mag nie onderskat word nie. Vervoer speel ’n belangrike rol in die bevordering van ’n persoon se lewenskwaliteit: dit verbind mense met mekaar en verskaf toegang tot die werksplek, diensteverskaffers, en vryetydsbesteding. Post-apartheid Suid-Afrika is egter nog steeds vasgevang in ’n nalatenskap van rasseskeiding. Die minderbevoorregtes, wat meestal aan die buitewyke van die stad woon, is geforseerde gebruikers van openbare vervoer, terwyl die neiging (onder die bevoorregtes) om privaatvoertuie te gebruik, aan die toeneem is.
Hierdie navorsingsprojek beveel dus aan dat ’n gebalanseerde, geïntegreerde en volhoubare vervoerstelsel bevorder moet word. ’n Sodanige stelsel sal help om die sosio-ekonomiese status van Suid-Afrika te bevorder. Dít kan net bereik word as alle landsburgers gelyke toegang tot ’n gebalanseeerde vervoernetwerk het. As ’n multimode-stelsel dus bevorder word, kan die tekortkominge van die huidige heterogene, nie-geïntegreerde stelsels oorkom word. Indien Suid-Afrika se vervoernetwerk ’n multimodale platform het, kan die landsburgers effektief en doeltreffend vervoer word sonder om die ekonomie, sosiale aangeleenthede of omgewing, tans en in die toekoms, in gedrang in te bring. Suid-Afrika sal boonop, met so ’n platform in plek, ook die nodige stimulus hê om die bestaande hulpbronne optimaal te gebruik.
Hierdie navorsingsprojek verskaf ’n (generiese) in-volgorde-benadering om ’n volhoubare, geïntegreerde openbare vervoerstelsel daar te stel. Die doel is om bewustheid van die voordele wat uit ’n multimodale platform spruit, sowel as die nodige stappe vir die uitvoering daarvan, te kweek. Die fokusarea van die navorsing is die Stad van Kaapstad se land-vervoernetwerke. Die Stad het ’n beheerfasiliteit waar vervoerdata versamel word. Dit staan bekend as die vervoer-beheersentrum (TMC: Transport Management Centre). Hierdie fasiliteit word as toonaangewend in die wêreld beskou. Die kenmerkende eienskappe van hierdie fasiliteit bied verder ook ’n goeie vertrekpunt vir die bevordering van ’n multimodale stelsel.
Die navorsing in hierdie veld het die volgende bydraende faktore, wat benodig word om die voorstelling te realiseer, geïdentifiseer. In die eerste plek moet die intelligente vervoerstelsels (ITS: Intelligent Transport Systems) geïntegreer word om ’n geïntegreerde volhoubare vervoerstelsel daar te stel. Indien ’n intelligente vervoerskema, gebaseer op tegnologiese inisiatiewe, aangemoedig word, sal die Stad van Kaapstad in die posisie wees om sy vervoerstelsel pro-aktief te bestuur deur meer effektief te monitor wat aangaan en meer akkuraat te voorspel wat in die toekoms mag gebeur. Tweedens moet daar ’n gesentraliseerde databasis geskep word. Met hierdie databasis sal die nodige integrasievereistes vir ’n multimodale vervoerstelsel, bereik word. Inligting kan dan gedeel word tussen privaat- en openbare landvervoer, asook tussen die beleggers en die operateurs van die verskillende vervoermodusse. ’n Voorbeeld van so ’n databasis is in Microsoft Access geskep en die modusse wat deel daarvan uitmaak, is: MyCiti, Metrorail en Golden Arrow Bus Services (GABS). Die data wat hierin vervat is, is histories, maar daar is vir intydse inligting voorsiening gemaak.
In die derde plek is die sukses van die Stad van Kaapstad se vervoerstelsel en die ontwikkeling van ’n multimodale stelsel afhanklik van die daarstelling van ’n effektiewe, gevorderde inligtingsstelsel vir pendelaars (ATIS: Advanced Traveller Information Systems). Die idee is om ’n multimodale vervoerstelsel as ’n gerieflike opsie onder pendelaars te bevorder. Dit kan bereik word deur inligting rakende reisbeplanning aan pendelaars daar te stel. Met die verkryging van sodanige kennis sal die pendelaar se weerstand teen verandering ook afneem. Om so ’n multimodale reisbeplanner (JP: Journey Planner) te ontwikkel, is die eenmodaal-netwerke gekombineer om ’n supernetwerk te skep. Dijkstra se algoritme is op die supernetwerk toegepas. Die algoritme is in Microsoft Excel se VBA (Visual Basic for Applications) geprogrammeer en dit bevat die volgende gebruikerskriteria, nl. die begin- en eindpunt, die gebruiker se modes-voorkeur en die gebruiker se gekose optimeringsvoorkeur van tyd of afstand.
Ten slotte kan gesê word dat inligting ’n groot rol in die mens se daaglikse lewe en aktiwiteite speel. Daar kan dus geredeneer word dat die sleutel tot suksesvolle vervoerdienste daarin lê om vir ingeligte pendelaars voorsiening te maak. As pendelaars ingelig is oor die stand van die vervoernetwerk maak dit hul houding meer positief. Verder, as pendelaars ook inligting oor reisbeplanning het, kan dit hul gevoel van onsekerheid en vrees jeens (veral) openbare vervoer teenwerk. Met al hierdie inligting tot sy beskikking kan ’n persoon dus sy eie keuses maak en dit lei daartoe dat die persoon meer in beheer voel. As ’n multimodale JP geskep word, voed dit die mens se begeerte vir meer inligting. En met ’n sodanige JP in plek, kan geïntegreerde pendel moontlik die norm word.
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Route Choice Behavior in Risky Networks with Real-Time InformationRazo, Michael D 01 January 2010 (has links) (PDF)
This research investigates route choice behavior in networks with risky travel times and real-time information. A stated preference survey is conducted in which subjects use a PC-based interactive maps to choose routes link-by-link in various scenarios. The scenarios include two types of maps: the first presenting a choice between one stochastic route and one deterministic route, and the second with real-time information and an available detour. The first type measures the basic risk attitude of the subject. The second type allows for strategic planning, and measures the effect of this opportunity on subjects' choice behavior.
Results from each subject are analyzed to determine whether subjects planned strategically for the en route information or simply selected fixed paths from origin to destination. The full data set is used to estimate route choice models that account for both risk attitude and strategic thinking. Estimation results are used to assess whether models that incorporate strategic behavior more accurately reflect route choice than do simpler path-based models.
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An adaptive strategy for providing dynamic route guidance under non-recurrent traffic congestionLee, Sang-Keon 06 June 2008 (has links)
Traffic congestion on urban road networks has been recognized as one of the most serious problems with which modern cities are confronted. It is generally anticipated that Dynamic Route Guidance Systems (DRGS) will play an important role in reducing urban traffic congestion and improving traffic flows and safety. One of the most critical issues in designing these systems is in the development of optimal routing strategies that would maximize the benefits to overall system as well as individual users.
Infrastructure based DRGS have advantage of pursuing system optimal routing strategy, which is more essential under abnormal traffic conditions such as non-recurrent congestion and natural disaster. However user compliance could be a problem under such a strategy, particularly when some of equipped drivers are urged not to choose minimum travel time path for the sake of improving the total network travel time. On the other hand, In-vehicle based DRGS can utilize the user-specified route selection criteria to avoid "Braess Paradox" under normal traffic conditions. However, it may be of little use under abnormal traffic conditions and high DRGS market penetration.
In conducting the comparative analysis between system optimal strategy and user equilibrium strategy, significant differences were found within the mid-range traffic demand. The maximum total travel time difference occurs when the level of traffic demand is half of the system capacity. At this point, system optimal route guidance strategy can save more than 11% of the total travel time of user equilibrium route guidance strategy.
The research proposes an adaptive routing strategy as an efficient dynamic route guidance under non-recurrent traffic congestion. Computation results show that there is no need to implement system optimal routing strategy at the initial stage of the incident. However, it is critical to use system optimal routing strategy as freeway and arterial are getting congested and the queue delay in freeway increases.
The adaptive routing strategy is evaluated using Traffic simulation model, INTEGRATION. According to simulation results using an ideal network, the travel time saving ratio is maximum when both arterial and freeway have normal traffic demand under incident. In case of a realistic network, the adaptive routing strategy also proved to save the total travel time between 3% to 10% over the traditional user equilibrium routing strategy. The reduction of total travel time increases as the incident duration increases. Consequently, it is concluded that the adaptive routing strategy for DRGS is more efficient than using user equilibrium routing strategy alone. / Ph. D.
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A Planning Model for Optimizing Locations of Changeable Message SignsHenderson, Jeffrey January 2004 (has links)
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.
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A Planning Model for Optimizing Locations of Changeable Message SignsHenderson, Jeffrey January 2004 (has links)
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.
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