ปัญหาการดำเนินงานของระบบขนส่งมวลชนและแนวทางการแก้ไข

บทคัดย่อระบบขนส่งมวลชนเป็นโครงสร้างพื้นฐานในการรองรับการเจริญเติบโตของสังคมโดยมีลักษณะของกิจการสำหรับการบริการซึ่งไม่แสวงหาผลกำไร ส่งผลให้เกิดความท้าทายในการดำเนินงานเพื่อให้เกิดคุณภาพในการให้บริการและผลกำไร องค์การขนส่งมวลชนกรุงเทพ(ขสมก.) เป็นหน่วยงานของรัฐที่ดูแลรับผิดชอบระบบการเดินรถโดยสารประจำทางในเขตกรุงเทพมหานครและปริมณฑลซึ่งประสบกับปัญหาขาดทุนสะสม การศึกษาและวิเคราะห์ระบบการเดินรถโดยสารประจำทางจึงมีความจำเป็นต่อการบรรเทาปัญหาดังกล่าว บทความนี้สรุปปัญหาของระบบขนส่งมวลชนจากทั้ง ขสมก. และองค์กรในต่างประเทศ ทบทวนผลการศึกษาและงานวิจัยด้านการจำลองระบบขนส่งมวลชนหรือระบบจราจรด้วยระบบคอมพิวเตอร์ซึ่งช่วยลดต้นทุนในการศึกษาพฤติกรรมและผลกระทบจากการเปลี่ยนแปลง รวมถึงนำเสนอแนวทางในการศึกษาและพัฒนาการดำเนินงานของ ขสมก. โดยการศึกษาความสิ้นเปลืองของต้นทุนการดำเนินงานจากการทับซ้อนของเส้นทางการเดินรถคำสำคัญ: ระบบขนส่งมวลชน ระบบการเดินรถโดยสารประจำทาง องค์การขนส่งมวลชนกรุงเทพ การจำลองด้วยระบบคอมพิวเตอร์ การทับซ้อนของเส้นทางการเดินรถAbstractPublic transportation plays a major role in being one of important infrastructures which supports the growth of society. As a service-oriented organization, making profits and providing good services are challenging. Bangkok Mass Transit Authority (BMTA) is a government agency which is mainly responsible for providing bus services in Bangkok and metropolitan areas. It has been struggling with accumulated losses. Proper studies and analyses on the bus system are therefore crucial for understanding and tackling such problem. This article summarizes the problems and suggestions addressed by BMTA and international agencies. Previous studies and researches on simulating public transport or traffic system on computer are reviewed. Moreover, the recommendations for future study on excessive operating costs of the existing overlapping bus routes are suggested.Keywords: Public Transportation, Bus Transport System, Bangkok Mass Transit Authority (BMTA), Computer Simulation, Overlapping Bus Route

Performance Analysis of Vertical Handover in Vehicular Ad-hoc Network Using Media Independent Handover Services

Next-generation of the mobile communication, network services allow users to move in freedom while accessing the Internet and network applications with seamless communication through the different wireless networks technologies. Integrating different system networks is called vertical handover which is critically a challenging task using the traditional decision algorithm for the next-generation networks. In this study, we proposed a simulation result of performance quality of service (QoS) of the vertical handover in vehicle-to- Infrastructure (V2I) on Road-Side Unit (RSU) between Wifi, WiMAX, and LTE networks using IEEE 802.21 Media Independent Handover (MIH) standard. The simulation is carried out using the NS-2 simulator and the VanetMobiSim traffic generator for the IEEE 802.21 MIH standard. The results show the performance analysis of IEEE 802.21 MIH in terms of handover latency, throughput, end-to-end delay and packet loss. Hence, this study will help and guide the Intelligent Transport System (ITS) and Telecommunication System (Telcos) provider in Malaysia to cater the problems of internet services by increasing the QoS of networks for the user's convenience

Performance analysis of vertical handover in vehicular ad-hoc network using media independent handover services

Next-generation of the mobile communication, network services allow users to move in freedom while accessing the Internet and network applications with seamless communication through the different wireless networks technologies. Integrating different system networks is called vertical handover which is critically a challenging task using the traditional decision algorithm for the next-generation networks. In this study, we proposed a simulation result of performance quality of service (QoS) of the vertical handover in vehicle-to Infrastructure (V2I) on Road-Side Unit (RSU) between Wifi, WiMAX, and LTE networks using IEEE 802.21 Media Independent Handover (MIH) standard. The simulation is carried out using the NS-2 simulator and the VanetMobiSim traffic generator for the IEEE 802.21 MIH standard.The results show the performance analysis of IEEE 802.21 MIH in terms of handover latency, throughput, end-to-end delay and packet loss. Hence, this study will help and guide the Intelligent Transport System (ITS) and Telecommunication System (Telcos) provider in Malaysia to cater the problems of internet services by increasing the QoS of networks for the user's convenience

The Impact of Driver Reaction in Cooperative Vehicle Safety Systems

Cooperative Vehicular Safety (CVS) has recently been widely studied in the field of automated vehicular systems. CVS systems help decrease the rates of accidents. However, implementing and testing CVS applications in real world is very costly and risky. Hence, most of the related research studies on CVS applications have relied mainly on simulations. In simulated CVS systems, it is important to consider all critical aspects of used models, and how these models affect one another. The movement model is a key component in the simulation study of CVS systems, which controls the mobility of vehicles (nodes) and responses to the continually changing acquiredinformation. However, existing mobility models are not created to take action(s) in response to hazardous situations (identified by situational awareness component). Integrating the reaction(s) to a hazardous alert is a missing element in current CVS system simulations. Hence to rectify this deficiency, this work is to incorporate a Driver’s Reaction Model (DReaM) that react and respond to hazard alerts, and studies the effect of main components of CVS system including the added model. We examined a simulation modeling framework that describes cooperative vehicle safety system as one unified model. The studied framework is powered by cooperation and communication between vehicles. Investigated elements are communication model, movement model, warning generation, and driver response to warning indicating an emergency of near to crash situation

Mobility Models for Vehicular Communications

The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-319-15497-8_11The experimental evaluation of vehicular ad hoc networks (VANETs) implies elevate economic cost and organizational complexity, especially in presence of solutions that target large-scale deployments. As performance evaluation is however mandatory prior to the actual implementation of VANETs, simulation has established as the de-facto standard for the analysis of dedicated network protocols and architectures. The vehicular environment makes network simulation particularly challenging, as it requires the faithful modelling not only of the network stack, but also of all phenomena linked to road traffic dynamics and radio-frequency signal propagation in highly mobile environments. In this chapter, we will focus on the first aspect, and discuss the representation of mobility in VANET simulations. Specifically, we will present the requirements of a dependable simulation, and introduce models of the road infrastructure, of the driver’s behaviour, and of the traffic dynamics. We will also outline the evolution of simulation tools implementing such models, and provide a hands-on example of reliable vehicular mobility modelling for VANET simulation.Manzoni, P.; Fiore, M.; Uppoor, S.; Martínez Domínguez, FJ.; Tavares De Araujo Cesariny Calafate, CM.; Cano Escribá, JC. (2015). Mobility Models for Vehicular Communications. En Vehicular ad hoc Networks. Standards, Solutions, and Research. Springer. 309-333. doi:10.1007/978-3-319-15497-8_11S309333Bai F, Sadagopan N, Helmy A (2003) The IMPORTANT framework for analyzing the impact of mobility on performance of routing protocols for adhoc networks. Elsevier Ad Hoc Netw1:383–403Baumann R, Legendre F, Sommer P (2008) Generic mobility simulation framework (GMSF). 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An evaluation methodology for reliable simulation based studies of routing protocols in VANETs

Vehicular Ad hoc networks (VANETs) have attracted much attention in the last decade. Many routing protocols have been proposed for VANETs and their performance is usually evaluated and compared using simulation-based studies. However, conducting reliable simulation studies is not a trivial task since many simulation parameters must be configured correctly. The selected parameters configuration can considerably affect the simulation results. This paper presents a methodology for conducting reliable simulations of routing protocols in VANETs urban scenarios. The proposed methodology includes relevant simulation aspects such as measurement period, selection of source-destination pairs for the communication traffic flows, number of simulations, mobility models based on road city maps, performance metrics and different analyses to evaluate routing protocols under different conditions. The proposed methodology is validated by comparing the simulation results obtained for Ad Hoc On-Demand Distance Vector (AODV) routing protocol with and without using the proposed methodology. The obtained results confirm that by using the proposed methodology, we can achieve more reliable simulations of VANETs routing protocols.Universidad de Sevilla. V Plan Propio de InvestigaciónMinisterio de Economía y Competitividad DPI2013-44278-

Symbiotic service composition in distributed sensor networks

To cope with the evergrowing number of colocated networks and the density they exhibit, we introduce symbiotic networks-networks that intelligently share resources and autonomously adapt to the dynamicity thereof. By allowing the software services provided in such networks to operate in an equally symbiotic manner, new opportunities for the so-called service compositions arise, which take advantage of the multitude of services and combine them to achieve goals set out by the individual networks. To accommodate services in large-scale symbiotic networks, including wireless sensor networks, we propose a software platform which autonomously constructs and orchestrates such compositions. Furthermore, upon changes in the infrastructure, the platform responds by adapting compositions to reflect the changed context. To enable the interaction between services offered by arbitrary partners, the platform deploys ontologies to achieve a common vocabulary and semantic rules to express the policies imposed by the networks involved. By applying the platform to typical scenarios from the field of sensor-augmented cargo transportation and logistics, we illustrate its applicability and, through performance evaluation, show a significant increase in process efficiency. Additionally, by means of a generic problem generator, we quantify the scalability of our platform and show the importance of an appropriate priority function, one of the core constituents of our service composition approach

Overlay networks for intelligent transportation systems

Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores - Major de Telecomunicações. Faculdade de Engenharia. Universidade do Porto. 200