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Design and Optimization of a Feeder Demand Responsive Transit System in El Cenizo,TXChandra, Shailesh 2009 August 1900 (has links)
The colonias along the Texas-Mexico border are one of the most rapidly growing areas
in Texas. Because of the relatively low income of the residents and an inadequate
availability of transportation services, the need for basic social activities for the colonias
cannot be properly met. The objectives of this study are to have a better comprehension
of the status quo of these communities by examining the potential demand for an
improved transportation service and evaluate the capacity and optimum service time
interval of a new demand responsive transit "feeder" service within one representative
colonia, El Cenizo. A comprehensive analysis of the results of a survey conducted
through a questionnaire is presented to explain the existing travel patterns and potential
demand for a feeder service.
The results of this thesis and work from the subsequent simulation analysis showed that
a single shuttle would be able to comfortably serve 150 passengers/day. It further
showed that the optimal cycle length between consecutive departures from the terminal
should be between 11-13 minutes for best service quality. This exploratory study should
serve as a first step towards improving transportation services within these growing underprivileged communities especially those with demographics and geography similar
to the target area of El Cenizo.
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Designing optimal demand-responsive transportation feeder systems and comparing performance in heterogeneous environmentsEdwards, Derek L. 27 August 2014 (has links)
The goal of this research is to develop a method of objectively comparing and optimizing the performance of demand-responsive transportation systems in heterogeneous environments. Demand-responsive transportation refers to modes of transportation that do not follow fixed routes or schedules, including taxis, paratransit, deviated-route services, ride sharing as well as other modes. Heterogeneous environments are transportation environments in which streets do not follow regular patterns, passenger behavior is difficult to model, and transit schedules and layouts are non-uniform. An example of a typical heterogeneous environment is a modern suburb with non-linear streets, low pedestrian activity, and infrequent or sparse transit service. The motivation for this research is to determine if demand-responsive transportation can be used to improve customer satisfaction and reduce operating costs in suburban and low-density urban areas where fixed-route transportation may be inefficient.
This research extends existing comparison and optimization techniques that are designed to work in homogeneous environments. Homogeneous environments refer to transportation systems where the streets follow regular and repeating patterns, passengers are evenly distributed throughout the system, and the transit system is easily modeled. The performance of systems with these characteristics can be approximated with closed-form analytical expressions representing passenger travel times, vehicle distances traveled, and other performance indicators. However, in the low-density urban areas studied in this research, the street patterns and transit schedules are irregular and passenger behavior is difficult to model. In these areas, analytical solutions cannot be found. Instead, this research develops a simulation-based approach to compare and optimize performance in these heterogeneous environments. Using widely-available route-planning tools, open-source transit schedules, and detailed passenger data, it is possible to simulate the behavior of transit vehicles and passengers to such an exacting degree that analytical solutions are not needed.
A major technical contribution of this research is the development of a demand-responsive transportation simulator to analyze performance of demand-responsive systems in heterogeneous environments. The simulator combines several open-source tools for route planning with a custom-built demand-responsive vehicle and passenger-itinerary optimizer to simulate individual vehicles and passengers within a large system. With knowledge of the street network, the transit schedule, passenger locations, and trip request times, the simulator will output exact passenger transit times, passenger travel distances, vehicle travel distance, and other performance indicators for a particular transportation setup in a given area.
The simulator is used to develop a method of comparing various demand-responsive and fixed-route systems. By predefining a set of performance indicators, such as passenger travel time and operating cost, the simulator can be used to ascertain the performance of a wide array of transportation systems. Comparing the weighted cost of each type of system permits a transportation engineer or planner to determine what type of system will provide the best results in a given area.
The simulator is extended to assist in optimization of the demand-responsive transportation system layout. A key problem that needs to be solved when implementing a demand-responsive system is to determine the size, shape, and location of the demand-responsive coverage areas, i.e., the areas in which passengers are eligible for demand-responsive transportation. Using a particle swarm optimization algorithm and the simulation-based comparison technique, the optimal size and shape for a demand-responsive coverage area can be determined.
The efficacy of the comparison and optimization techniques is demonstrated within the city of Atlanta, GA. It is shown that for certain areas of the city of Atlanta, demand-responsive transportation is more efficient than the currently implemented fixed-route system. Depending on the objective of the transportation planner, passenger satisfaction as well as operating costs can be improved by implementing a demand-responsive system in certain low-density areas.
The techniques introduced in this research, and the simulation tool developed to implement those techniques, provide a repeatable, accurate, and objective method with which to optimize and compare demand-responsive transportation systems in heterogeneous environments.
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Demand Responsive Planning : A dynamic and responsive planning framework based on workload control theory for cyber-physical production systemsAkillioglu, Hakan January 2015 (has links)
Recent developments in the area of Cyber-Physical Production Systems prove that high technology readiness level is already achieved and industrialization of such technologies is not far from today. Although these technologies seem to be convenient in providing solutions to environmental uncertainties, their application provides adaptability only at shop floor level. Needless to say, an enterprise cannot reach true adaptability without ensuring adaptation skills at every level in its hierarchy. Commonly used production planning and control approaches in industry today inherit from planning solutions which are developed in response to historical market characteristics. However, market tendency in recent years is towards making personalized products a norm. The emerging complexity out of this trend obliges planning systems to a transition from non-recurring, static planning into continuous re-planning and re-configuration of systems. Therefore, there is a need of responsive planning solutions which are integrated to highly adaptable production system characteristics. In this dissertation, Demand Responsive Planning, DRP, is presented which is a planning framework aiming to respond to planning needs of shifting trends in both production system technologies and market conditions. The DRP is based on three main constructs such as dynamicity, responsiveness and use of precise data. These features set up the foundation of accomplishing a high degree of adaptability in planning activities. By this means, problems from an extensive scope can be handled with a responsive behavior (i.e. frequent re-planning) by the use of precise data. The use of precise data implies to execute planning activities subject to actual demand information and real-time shop floor data. Within the context of the DRP, both a continuous workload control method and a dynamic capacity adjustment approach are developed. A test-bed is coded in order to simulate proposed method based on a system emulation reflecting the characteristics of cyber-physical production systems at shop floor level. Continuous Precise Workload Control, CPWLC, method is a novel approach aiming at precise control of workload levels with the use of direct load graphs. Supported by a multi-agent platform, it generates dynamic non-periodic release decisions exploiting real time shop floor information. As a result, improved shop floor performances are achieved through controlling workload levels precisely by the release of appropriate job types at the right time. Presented dynamic capacity adjustment approach utilizes rapid re-configuration capability of cyber-physical systems in achieving more frequent capacity adjustments. Its implementation architecture is integrated to the CPWLC structure. By this means, a holistic approach is realized whereby improved due date performance is accomplished with minimized shop floor congestion. Hence, sensitivity to changing demand patterns and urgent job completions is improved. / <p>QC 20150907</p>
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A multi-criteria approach for the design and evaluation of demand responsive transport (DRT) servicesAndrade, Miguel Jorge Raposo Nunes de January 2008 (has links)
Demand responsive transport services are nowadays an established and recognized way to provide better social inclusion to non-urban, low population density areas. The concept has its origins in the 70´s in the USA, but just recently the advances in technology made this type of service more economically attractive. Therefore is of no surprise that this kind of transportation is starting to be a serious option in several regions across Europe. The European Commission has been promoting projects to study and implement DRT services. One of these projects, MASCARA (deMand responsive trAnsport service for increasing Social Cohesion in urbAn/Rural Areas), involved a team from the Engineering School of the University of Porto, with the participation of the author. The MASCARA project was designed to promote the cooperation between several regions in Europe to share knowledge about DRT services, evaluating DRT pilots and DRT feasibility studies. This dissertation focus on the design of a framework to help this evaluation. The work resulted in combining two known multi-criteria methodologies, namely AHP and TOPSIS. Albeit these methods were designed to help choosing (ranking) between two or more possible scenarios, the proposed framework is able to evaluate and score one scenario situations. This work can be viewed as having two parts: the first one (from chapter 1 to chapter 4) deals with the design of the framework and methodology. From chapter 5 onwards the practical application is adressed. The author work was focused on the design and software implementation of the evaluation framework.
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Optimal Design of Demand-Responsive Feeder Transit ServicesLi, Xiugang 2009 August 1900 (has links)
The general public considers Fixed-Route Transit (FRT) to be inconvenient
while Demand-Responsive Transit (DRT) provides much of the desired flexibility with a
door-to-door type of service. However, FRT is typically more cost efficient than DRT to
deploy. Therefore, there is an increased interest in flexible transit services including all
types of hybrid services that combine FRT and pure DRT. The demand-responsive
feeder transit, also known as Demand-Responsive Connector (DRC), is a flexible transit
service because it operates in a demand-responsive fashion within a service area and
moves customers to/from a transfer point that connects to a FRT network. In this
research we develop analytical models, validated by simulation, to design the DRC
system.
Feeder transit services are generally operated with a DRC policy which might be
converted to a traditional FRT policy for higher demand. By using continuous
approximations, we provide an analytical modeling framework to help planners and
operators in their choice of the two policies. We compare utility functions of the two policies to derive rigorous analytical and approximate closed-form expressions of critical
demand densities. They represent the switching conditions, that are functions of the
parameters of each considered scenario, such as the geometry of the service area, the
vehicle speed and also the weights assigned to each term contributing to the utility
function: walking time, waiting time and riding time.
We address the problem faced by planners in determining the optimal number of
zones for dividing a service area. We develop analytical models representing the total
cost functions balancing customer service quality and vehicle operating cost. We obtain
close-form expressions for the FRT and approximation formulas for the DRC to
determine the optimal number of zones.
Finally we develop a real-case application with collected customer demand data
and road network data of El Cenizo, Texas. With our analytical formulas, we obtain the
optimal number of zones, and the times for switching FRT and DRC policies during a
day. Simulation results considering the road network of El Cenizo demonstrate that our
analytical formulas provide good estimates for practical use.
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Determinants of customer satisfaction with a true door-to-door DRT service in rural GermanyAvermann, Niklas, Schlüter, Jan 25 September 2020 (has links)
The effects of demographic change and the lack of acceptance represent some of the main problems for the public transport infrastructure in rural areas. As a consequence, the development of new transport service options becomes especially relevant for rural communities. The Max-Planck-Institute for Dynamics and Self-Organization developed a new form of Demand Responsive Transport the EcoBus to examine the viability of new DRT systems in rural Germany. Our work draws on customer satisfaction data during the trial runs of the EcoBus. Based on the survey data, this paper develops regression models to explain the determinants of DRT customer satisfaction. Our main findings include the importance of waiting times and the ease of entry for overall customer satisfaction. Nevertheless, we found no evidence that the presence of other guests in the vehicle had any negative impact on customer satisfaction. Findings of other works that women are significantly more likely to use DRT services could not be validated from our data.
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Effektivare kollektivtrafik genom interaktiva DRT-tjänsterIversen, John, Nilsson, Adam January 2020 (has links)
Ökad miljömedvetenhet, växande klimatpåverkan och en fortsatt teknologisk utveckling gör att demand responsive transportation (DRT), ses som ett allt mer attraktivt alternativ till traditionell kollektivtrafik för att resa hållbart. Den här uppsatsen undersöker vilka skillnader det finns med DRT-implementationer på landsbygd jämfört med i stadsmiljö, samt vilken roll interaktivitet mellan operatör och resenär kan spela för ett DRT-systems effektivitet.För att svara på detta används en systematisk litteraturstudie och två fallstudier. Resultaten visar att DRT generellt lämpar sig bättre för landsbygd än i stadsmiljö och att DRT fungerar bättre som ett komplement till traditionell kollektivtrafik än som ersättning av den. DRTs potentiella roll i samhället och möjliga framtida forskningsriktningar presenteras och diskuteras. / An increased awareness of environmental issues, climate changes and a continuing technological development makes demand responsive transportation (DRT) a more likely and attractive option for public transportation. This paper examines the differences between various DRT implementations in rural areas compared to cities. It also examines what role interacitivity can play to increase a DRT-systems efficiency.To answer this, a systematic literature review is conducted along with two case studies. The results show that DRT is generally more suited to rural areas compared to cities. It also shows that DRT works better as a complement to public transport, rather than a replacment of it.The potential role of DRT in a society and future research matters are presented and discussed.
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Accessibility, how it is understood by planners and experienced by citizens : Planners' and citizens' perceptions of how Demand Responsive Transport can increase accessibility in suburban areas.Reinhardt, Albin January 2023 (has links)
Accessibility is a well-established concept that appears frequently in urban planning. It refers to the ability of citizens to actively participate in society. Nevertheless, inaccessibility is experienced in many places, which can lead to exclusion of citizens. Against this background, this master's thesis aims to center on the concept of accessibility and examine it from two perspectives - strategic urban planners and individuals. The thesis examines how accessibility is interpreted by strategic urban planners in the two suburban municipalities of Botkyrka and Huddinge and how it is experienced by a group of “low-skilled” workers in an area where there are identified shortcomings in traffic planning. The thesis studies how this group experiences their accessibility in their daily commute before and after they test a Demand-Responsive Transport (DRT) service. The theoretical framework consists of the concepts of accessibility strategies, transport and accessibility, objective accessibility, perceived accessibility, accessibility barriers and social exclusion, which are used to analyze the two different perspectives. The results show that strategic planners view accessibility as the relationship between citizens and destination points, and that inaccessible places are mainly associated with rural or sparsely populated areas. At the same time, the thesis shows that the workers experience inaccessibility in their daily trips, despite living in surrounding municipalities. The results also show the identified potentials and risks of DRT in suburban environments from the perspective of both strategic planners and individuals. The results show that DRT reduced travel times for the workers. Furthermore, perspectives such as reliability, safety and equity are highlighted as important aspects in the design of DRT services.
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A Framework for Evaluation and Design of an Integrated Public Transport SystemHäll, Carl Henrik January 2006 (has links)
<p>Operators of public transport always try to make their service as attractive as possible, to as many persons as possible and in a so cost effective way as possible. One way to make the service more attractive, especially to elderly and disabled, is to offer door-to-door transportation. The cost for the local authorities to provide this service is very high and increases every year.</p><p>To better serve the needs of the population and to reduce the cost for transportation of elderly and disabled, public transportation systems are evolving towards more flexible solutions. One such flexible solution is a demand responsive service integrated with a fixed route service, together giving a form of flexible public transport system. The demand responsive service can in such a system be used to carry passengers from their origin to a transfer location to the fixed route network, and/or from the fixed route network to their destination.</p><p>This thesis concerns the development of a framework for evaluation and design of such an integrated public transport service. The framework includes a geographic information system, optimization tools and simulation tools. This framework describes how these tools can be used in combination to aid the operators in the planning process of an integrated service. The thesis also presents simulations made in order to find guidelines of how an integrated service should be designed. The guidelines are intended to help operators of public transport to implement integrated services and are found by evaluating the effects on availability, travel time, cost and other service indicators for variations in the design and structure of the service.</p><p>In a planning system for an integrated public transport service, individual journeys must in some way be scheduled. For this reason the thesis also presents an exact optimization model of how journeys should be scheduled in this kind of service.</p> / Report code: LiU-TEK-LIC- 2006:38
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Information flows in Demand Responsive Public Transport : Interactivity, information, and flexibility in a modern ridesharing serviceHamnebo, Karl, Askfelt, Oscar January 2021 (has links)
The focus of this thesis is to study what and how information flows can be used to improve Demand responsive transport (DRT) systems by understanding potential users and how they could be willing to participate in DRT to a higher degree. The viewpoint of this thesis tends to lean towards a DRT service of a public transport type. This thesis studies users in relation to what interaction and information they perceive to be needed in dealing with a DRT service and the different pros and cons with various approaches. The study gathers information by performing adapted qualitative interviews with a select number of users between the ages of 20-35. The participants give their views on three DRT scenarios and reflect on DRT in general as a concept presented to them through a tangible mocked-up interactive prototype. The thesis makes several distinct findings. The importance of pricing a DRT service correctly is vital to the users, as several participants in the study relied on pricing for decision-making. It also finds that the usage of zones as nomenclature is confusing to many users. The services must be dependable and punctual to both attract users, keep users, and build trust among the general populace. This study shows that DRT services could be a difficult concept to introduce to users. DRT could be introduced as a complement or as an alternative to conventional public transport. An important factor is a well-designed flow of information in the application to keep the user engaged and involved. It is shown that the usability of the application is a cornerstone for a theoretical DRT service to excel. Context is important where DRT and ridesharing would have a higher success rate. Nighttime in urban areas could be a niche market, due to the irregularity, delay, or interruption of regular public transport services at these hours.
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