scholarly journals A Capacity-Restraint Transit Assignment Model When a Predetermination Method Indicates the Invalidity of Time Independence

2015 ◽  
Vol 2015 ◽  
pp. 1-12
Author(s):  
Haoyang Ding ◽  
Yu Bao ◽  
Sida Luo ◽  
Hanxia Shen ◽  
Wei Wang ◽  
...  

The statistical independence of time of every two adjacent bus links plays a crucial role in deciding the feasibility of using many mathematical models to analyze urban transit networks. Traditional research generally ignores the time independence that acts as the ground of their models. Assumption is usually made that time independence of every two adjacent links is sound. This is, however, actually groundless and probably causes problematic conclusions reached by corresponding models. Many transit assignment models such as multinomial probit-based models lose their effects when the time independence is not valid. In this paper, a simple method to predetermine the time independence is proposed. Based on the predetermination method, a modified capacity-restraint transit assignment method aimed at engineering practice is put forward and tested through a small contrived network and a case study in Nanjing city, China, respectively. It is found that the slope of regression equation between the mean and standard deviation of normal distribution acts as the indicator of time independence at the same time. Besides, our modified assignment method performs better than the traditional one with more reasonable results while keeping the property of simplicity well.

2020 ◽  
Vol 47 (8) ◽  
pp. 898-907 ◽  
Author(s):  
Islam Kamel ◽  
Amer Shalaby ◽  
Baher Abdulhai

Although the traffic and transit assignment processes are intertwined, the interactions between them are usually ignored in practice, especially for large-scale networks. In this paper, we build a simulation-based traffic and transit assignment model that preserves the interactions between the two assignment processes for the large-scale network of the Greater Toronto Area during the morning peak. This traffic assignment model is dynamic, user-equilibrium seeking, and includes surface transit routes. It utilizes the congested travel times, determined by the dynamic traffic assignment, rather than using predefined timetables. Unlike the static transit assignment models, the proposed transit model distinguishes between different intervals within the morning peak by using the accurate demand, transit schedule, and time-based road level-of-service. The traffic and transit assignment models are calibrated against actual field observations. The resulting dynamic model is suitable for testing different demand management strategies that impose dynamic changes on multiple modes simultaneously.


2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Zhenyu Mei ◽  
Dianhai Wang ◽  
Fujian Wang ◽  
Jun Chen ◽  
Wei Wang

A public transit network differs from a general road network. The passenger flow of bus stops and the limited capacity of buses have a greater effect than road traffic flow on the running time of buses. As a result, conventional public transit assignment models that adopt the econometric road network path concept have numerous limitations. Based on the analysis, the generalized bus trip time chain is analyzed, and the concept of a congestion function is proposed to describe the relationship between trip resistance and flow in the current paper. On the premise of this study, the transit network resistance function is formed and the multiroute probit-based loading model is established. With using STOCH or Dial's algorithm, the process of distribution is proposed. Finally, the model is applied to the transit network assignment of Deqing Town in Zhejiang Province. The result indicates that the model can be applied to practical operations with high-precision results.


2015 ◽  
Vol 50 (1) ◽  
pp. 50-68 ◽  
Author(s):  
Bingfeng Si ◽  
Liping Fu ◽  
Jianfeng Liu ◽  
Sajad Shiravi ◽  
Ziyou Gao

2013 ◽  
Vol 368-370 ◽  
pp. 1876-1880 ◽  
Author(s):  
Ying Zeng ◽  
Jun Li ◽  
Hui Zhu

Few studies have adequately focused on passenger route choice behavior with congestion consideration, or provided useful guidance on passenger route choice and hence the transit assignment model, which is the writing motivation of this paper. With congestion consideration, travel cost is assessed and and ways to reduce it also identified. Finally, an actual transit network of Chengdu is used as a case study to demonstrate the benefits of the proposed model. The result indicates that the vehicle capacity is an important factor that cant be ignored and a better understanding of passenger route behavior could significantly benefit public transit system.


2014 ◽  
Vol 13 (8) ◽  
pp. 4723-4728
Author(s):  
Pratiksha Saxena ◽  
Smt. Anjali

In this paper, an integrated simulation optimization model for the assignment problems is developed. An effective algorithm is developed to evaluate and analyze the back-end stored simulation results. This paper proposes simulation tool SIMASI (Simulation of assignment models) to simulate assignment models. SIMASI is a tool which simulates and computes the results of different assignment models. This tool is programmed in DOT.NET and is based on analytical approach to guide optimization strategy. Objective of this paper is to provide a user friendly simulation tool which gives optimized assignment model results. Simulation is carried out by providing the required values of matrix for resource and destination requirements and result is stored in the database for further comparison and study. Result is obtained in terms of the performance measurements of classical models of assignment system. This simulation tool is interfaced with an optimization procedure based on classical models of assignment system. The simulation results are obtained and analyzed rigorously with the help of numerical examples. 


2020 ◽  
Vol 17 (2) ◽  
pp. 291-320
Author(s):  
Asep Saefullah

Tulisan ini membahas fenomena penyebaran kitab-kitab cetak keaga­maan di Jawa Barat, khususnya di Sukabumi dan Cianjur. Jenis kitab ini biasanya menggunakan tulisan Arab dengan bahasa Sunda dan menggu­nakan aksara Pegon. Kitab-kitab cetak dari jenis-jenis itu diproduksi dan direproduksi, dan masih digunakan sampai hari ini. Oleh karena itu, fenomena ini dapat disebut sebagai “living tradition”. Pengumpulan data dilakukan dengan melacak dan merekam kitab-kitab yang diproduksi (disalin atau dikarang) dan direproduksi (dicetak atau digandakan) dengan metode seder­hana, yakni fotocopi dan pencetakan tradisional seperti stensil, sablon, dan "cetak toko". Tulisan ini bertujuan untuk memetakan dan merevisi kategorisasi kitab-kitab tersebut dari kajian terdahulu berdasarkan jenis karya, seperti karangan asli, tuqilan, terjemahan, syarḥ (penjelasan), khulasah (ringkasan) yang lain, dan juga berdasarkan bahasa dan aksara yang digunakan. Selain itu, tulisan ini juga mengamati lembaga-lembaga atau individu-individu yang masih mereproduksi buku-buku (kitab-kitab) keagamaan sederhana seperti perusahaan percetakan atau pesantren yang menerbitkan kitab-kitab tersebut. Pada akhir artikel ini, ada beberapa saran dalam upaya untuk melestarikan kitab-kitab cetak dan karya-karya tersebut.Kata kunci: kitab, jenis karya, pencetakan tradisional, Sunda, Pegon, Jawa Barat This paper discusses the phenomenon of the spreading of religious printed books (kitabs) in West Java, especially in Sukabumi and Cianjur, which are characterized by the use of Arabic writing in Sundanese (or known as Pegon script). The printed books (Kitabs) of those types are produced and reproduced, and are still used to this day. Therefore, this phenomenon can be called as a “living tradition”. Data collection was conducted by tracing and recording religious books (kitabs) that are pro-duced (rewritten or compossed) and reproduced (printed or duplicated) with a simple method, known as photocopying and traditional printing such as stencils, screen printing, and “shop printing”. This paper aims to map and revise the categorization of these Kitabs from previous studies based on the types of works including original essays, tuqilan (quotations), translation, sharh (explanation), khulaṣah (summary), or the other, and also based on the language and the script used. In addition, this paper also observes the institutions or individuals that are still reproducing these printed religious books such as the printing company or pesantren that publish such kitabs. At the end of this article, there are some suggestions in attempts to preserve those printed kitabs and the works.Keywords: Kitabs, type of work, traditional printing, Sunda, Pegon, West Java


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