scholarly journals Intersection Signal Timing Optimisation for an Urban Street Network to Minimise Traffic Delays

2021 ◽  
Vol 33 (4) ◽  
pp. 579-592
Author(s):  
Manel Terraza ◽  
Ji Zhang ◽  
Zongzhi Li
Keyword(s):  
Urban Areas ◽  
Travel Demand ◽  
Computational Study ◽  
Demand Forecasting ◽  
Central Business District ◽  
Signal Timing ◽  
Vehicular Traffic ◽  
Street Network ◽  
Urban Street ◽  
Pedestrian Delays

The ever-increasing travel demand outpacing available transportation capacity especially in the U.S. urban areas has led to more severe traffic congestion and delays. This study proposes a methodology for intersection signal timing optimisation for an urban street network aimed to minimise intersection-related delays by dynamically adjusting green splits of signal timing plans designed for intersections in an urban street network in each hour of the day in response to varying traffic entering the intersections. Two options are considered in optimisation formulation, which are concerned with minimising vehicle delays per cycle, and minimising weighted vehicle and pedestrian delays per cycle calculated using the 2010 Highway Capacity Manual (HCM) method. The hourly vehicular traffic is derived by progressively executing a regional travel demand forecasting model that could handle interactions between signal timing plans and predicted vehicular traffic entering intersections, coupled with pedestrian crossing counts. A computational study is conducted for methodology application to the central business district (CBD) street network in Chicago, USA. Relative weights for calculating weighted vehicle and pedestrian delays, and intersection degrees of saturation are revealed to be significant factors affecting the effectiveness of network-wide signal timing optimisation. For the current study, delay reductions are maximised using a weighting split of 78/22 between vehicle and pedestrian delays.

Simplified Approaches to Ferry Travel Demand Forecasting

1997 ◽  
Vol 1608 (1) ◽  
pp. 17-29 ◽  
Author(s):  
Joseph P. Savage
Keyword(s):  
Rural Areas ◽  
Urban Areas ◽  
Travel Demand ◽  
Time Series Data ◽  
Linear Trend ◽  
Demand Forecasting ◽  
Series Data ◽  
Linear Regression Models ◽  
Travel Demand Forecasting ◽  
Socioeconomic Data

Large ferry systems and ferry systems operating in major urban areas can often rely on regional travel models using the traditional four-step travel demand forecasting process to predict ridership levels for their routes. However, smaller agencies and agencies in rural areas often do not have either the data or the resources to develop and implement complex forecasting models for their systems. A variety of simplified forecasting methods are reviewed that can be implemented with inexpensive, commercially available software using ferry traffic counts and readily available socioeconomic data from published sources. Data from the Woods Hole, Martha’s Vineyard and Nantucket Steamship Authority are used to illustrate and compare the applications of the following methods: simple annual compound growth rate (5- or 10-year historical trend, 12-month moving totals, weighted trends), simple linear trend extrapolation of time series data, and simple and multiple linear regression models using population, employment, and other independent variables for available outside sources.

scholarly journals Method of the Analysis of the Connectivity of Road and Street Network in Terms of Division of the City Area

Computation ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 54 ◽  
Author(s):  
Piotr Soczówka ◽  
Renata Żochowska ◽  
Grzegorz Karoń
Keyword(s):  
Urban Areas ◽  
Travel Demand ◽  
Transportation Network ◽  
Main Task ◽  
Street Network ◽  
Large Area ◽  
Basic Field ◽  
City Area ◽  
The Road ◽  
The City

The transport system of a Smart City consists of many subsystems; therefore, the modeling of the transportation network, which maps its structure, requires consideration of both the connections between individual subsystems and the relationships within each of them. The road and street network is one of the most important subsystems, whose main task is to ensure access to places generating travel demand in the city. Thus, its effectiveness should be at an appropriate level of quality. Connectivity is one of the most important characteristics of a road and street network. It describes how elements of that network are connected, which translates to travel times and costs. The analysis of the connectivity of the road and street network in urban areas is often conducted with the application of topological measures. In the case of a large area of the city, such analysis requires its division into smaller parts, which may affect the computational results of these measures; therefore, the main goal of the study was to present a method of performing analysis based on the computation of numerical values of selected measures of connectivity of road and street network, for a city area divided into fields of regular shape. To achieve that goal, the analyzed area was split into a regular grid. Subsequently, numerical values of the chosen measures of connectivity were calculated for each basic field, and the results allowed us to determine whether they are influenced by the method of division of the area. Obtained results showed that the size of the basic field influences the numerical values of measures of connectivity; however that influence is different for each of the selected measures.

scholarly journals The Impact of the Ring Roads on the Location Pattern of Shops in Town and City Centres. A Space Syntax Approach

2021 ◽  
Vol 13 (7) ◽  
pp. 3927
Author(s):  
Akkelies van Nes
Keyword(s):  
Urban Areas ◽  
Space Syntax ◽  
Optimal Location ◽  
Spatial Integration ◽  
Street Network ◽  
Location Pattern ◽  
Ring Road ◽  
Road Projects ◽  
The Impact ◽  
City Centres

This contribution demonstrates how inner ring roads change the location pattern of shops in urban areas with the application of the space syntax method. A market rational behaviour persists, in that shop owners always search for an optimal location to reach as many customers as possible. If the accessibility to this optimal location is affected by changes in a city’s road and street structure, it will affect the location pattern of shops. Initially, case studies of inner ring road projects in Birmingham, Coventry, Wolverhampton, Bristol, Tampere, and Mannheim show how their realisation affect the spatial structure of the street network of these cities and the location pattern of shops. The results of the spatial integration analyses of the street and road network are discussed with reference to changes in land-use before and after the implementation of ring roads, and current space syntax theories. As the results show, how an inner ring road is connected to and the type of the street network it is imposed upon dictates the resulting location pattern of shops. Shops locate and relocate themselves along the most spatially-integrated streets. Evidence on how new road projects influence the location pattern of shops in urban centres are useful for planning sustainable city centres.

scholarly journals Modelling Pluvial Flooding in Urban Areas Coupling the Models Iber and SWMM

Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2647
Author(s):  
Esteban Sañudo ◽  
Luis Cea ◽  
Jerónimo Puertas
Keyword(s):  
Urban Areas ◽  
Flow Model ◽  
Overland Flow ◽  
Drainage System ◽  
Urban Drainage ◽  
Dynamic Link Library ◽  
Storm Water Management Model ◽  
Urban Street ◽  
Sewer Network ◽  
Overland Flow Model

Dual urban drainage models allow users to simulate pluvial urban flooding by analysing the interaction between the sewer network (minor drainage system) and the overland flow (major drainage system). This work presents a free distribution dual drainage model linking the models Iber and Storm Water Management Model (SWMM), which are a 2D overland flow model and a 1D sewer network model, respectively. The linking methodology consists in a step by step calling process from Iber to a Dynamic-link Library (DLL) that contains the functions in which the SWMM code is split. The work involves the validation of the model in a simplified urban street, in a full-scale urban drainage physical model and in a real urban settlement. The three study cases have been carefully chosen to show and validate the main capabilities of the model. Therefore, the model is developed as a tool that considers the main hydrological and hydraulic processes during a rainfall event in an urban basin, allowing the user to plan, evaluate and design new or existing urban drainage systems in a realistic way.

Urban Transportation Planning for Air Quality Management: Case Study in Delhi, India, of Role of Social and Economic Costs in Welfare Maximization of Mobility Choice

2002 ◽  
Vol 1817 (1) ◽  
pp. 42-49 ◽  
Author(s):  
Karolin Kokaz ◽  
Peter Rogers
Keyword(s):  
Air Pollution ◽  
Growth Rates ◽  
Urban Areas ◽  
Travel Demand ◽  
Urban Air Pollution ◽  
Sustainable Transportation ◽  
Transport Sector ◽  
Large Cities ◽  
Environmental Goals ◽  
Management Case Study

Recent economic expansion and population growth in developing countries have had a big impact on the development of large cities like Delhi, India. Accompanied by Delhi’s rapid spatial growth over the last 25 years, urban sprawl has contributed to increased travel. The vehicle fleet projected at current growth rates will result in more than 13 million vehicles in Delhi in 2020. Planning and managing such a rapidly growing transport sector will be a challenge. Choices made now will have effects lasting well into the middle of the century. With such rapid transport growth rates, automobile emissions have become the fastest increasing source of urban air pollution. In India, most urban areas, including Delhi, already have major air pollution problems that could be greatly exacerbated if growth of the transport sector is managed unwisely. The transport plans designed to meet such large increases in travel demand will have to emphasize the movement of people, not vehicles, for a sustainable transportation system. Therefore, a mathematical model was developed to estimate the optimal transportation mix to meet this projected passenger-km demand while satisfying environmental goals, reducing congestion levels, and improving system and fuel efficiencies by exploiting a variety of policy options at the minimum overall cost or maximum welfare from transport. The results suggest that buses will continue to satisfy most passenger transport in the coming decades, so planning done in accordance with improving bus operations is crucial.

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