scholarly journals The Effect of Modifying Double Continuous Flow Intersections Layout Geometric Features on their Operation

2021 ◽  
Vol 15 (1) ◽  
pp. 1-10
Author(s):  
Ibrahim Khliefat ◽  
Ahmad Deeb ◽  
Mohammad Mubarak ◽  
Mohammad Naser
Keyword(s):  
Urban Areas ◽  
Continuous Flow ◽  
Simulation Models ◽  
Intersection Angle ◽  
Left Turn ◽  
Limited Space ◽  
Operational Characteristics ◽  
Layout Geometry ◽  
The Cross ◽  
And Performance

Introduction: Continuous flow interventions were first introduced as an alternative to improve traffic operations in the intersections with severe congestion caused by heavy left-turn movements. Objective: This study quantified the effect of modifying the intersection angles of Double Continuous Flow Intersections (DCFI) on their operational characteristics. Mainly, the effects of changing the intersection angle between the different approaches of the main intersection and the angle of the minor cross-over intersections were investigated. Methods: VISSIM software simulation models were used for modifying several design features related to the DCFI and the operational performance was compared between the different simulation scenarios. Results and Discussion: Changes to the cross-over intersection angle increase the safety levels by providing better channelization of traffic movements on the minor intersections of the DCFI and reduce the intersection footprint to be used at high-density urban locations. Increasing the cross-over intersection angle and changing the layout geometry have adverse effects on the capacity of the conventional DCFI. This is mainly because of the added curvature in the intersection approaches which reduces the vehicle speeds, therefore reducing the overall capacity of the modified intersection when compared to the conventional DCFI. However, the total footprint for the intersection is reduced for the modified layout geometry, which improves the capacity of the DCFI. Conclusion: The study has explored the effects of modifying the DCFI intersection angles to fit the limited space in major urban areas on the capacity and performance of the intersection. It showed that DCFI designs could be applied in areas with limited space availability and skewed intersection angles.

A New Continuous Flow Intersection for Urban Road: Architecture, Design, and Simulation

2012 ◽  
Vol 209-211 ◽  
pp. 677-682 ◽  
Author(s):  
Qiu Chen Liu ◽  
Lun Zhang ◽  
Wen Chen Yang
Keyword(s):  
Traffic Control ◽  
Continuous Flow ◽  
Left Turn ◽  
Urban Road ◽  
Traffic Efficiency ◽  
Traffic Conditions ◽  
Simulation Results ◽  
Low Efficiency ◽  
And Performance ◽  
Traffic Organization

In the light that heavy left-turn vehicles and oncoming vehicles conflict at conventional intersection(CI), leading to discontinuity and low efficiency of traffic flow, this paper presents a new continuous flow intersection(CFI) for urban roads. The geometry physical model and design principles of the CFI are illustrated and the CFI is designed from following three aspects: traffic space, traffic organization and traffic control. Experiments taking the CI and corresponding the CFI as the reseach objects are carried on, and performance of the proposed the CFI is validated via VISSIM. Extensive simulation results under five traffic conditions have demonstrated the potential of the proposed the CFI for improvement of traffic efficiency, and the applicability of the CFI in China is discussed considering the characteristics of domestic urban intersections and it indicates that the CFI could be applied to domestic suburb roads.

scholarly journals Estimate of Secondary NO2 Levels at Two Urban Traffic Sites Using Observations and Modelling

2020 ◽  
Vol 12 (19) ◽  
pp. 7897 ◽  
Author(s):  
Grazia Ghermandi ◽  
Sara Fabbi ◽  
Giorgio Veratti ◽  
Alessandro Bigi ◽  
Sergio Teggi
Keyword(s):  
Urban Areas ◽  
Transport Model ◽  
Simulation Models ◽  
Particle Dispersion ◽  
Reggio Emilia ◽  
Urban Traffic ◽  
Chemical Transport Model ◽  
Urban Background ◽  
Regulatory Limits ◽  
And Performance

Assessing secondary and primary NO2 in urban areas is important to support carefully designed environmental policies, particularly in areas with recurrent exceedance of NO2 regulatory limits. The share of secondary NO2 was preliminary estimated in intense traffic areas of Modena and Reggio Emilia (Northern Italy) by the combined analysis of regulatory air quality observations at urban traffic and urban background conditions. In addition simulations performed by the Lagrangian particle dispersion models Micro SWIFT SPRAY and the chemical transport model WRF-Chem were performed. The former was applied on the urban area representative of traffic conditions for both cities, in winter. The latter was applied twice in Modena, both with and without urban traffic emissions. Results suggest a large amount of secondary NO2 mainly at the Modena traffic site, and a better representativity of background conditions of the corresponding urban station in Reggio Emilia. NOx levels simulated by WRF-Chem show good results at Modena urban background and performance in line with reference benchmark values in reproducing observed NO2 and NOx concentrations at rural background sites, although a non-negligible bias in simulated urban NO2 remained. Overall the simulation models suggest that contribution to atmospheric NOx by domestic heating or industrial combustion emissions are not as relevant compared to traffic, consistently with the local emission inventory.

scholarly journals Use of simulation model for measurement of MilkRun system performance

2019 ◽  
Vol 9 (1) ◽  
pp. 600-605 ◽  
Author(s):  
Gabriel Fedorko ◽  
Martin Vasil ◽  
Michaela Bartosova
Keyword(s):  
Simulation Model ◽  
Production Systems ◽  
Operational Performance ◽  
Transport Systems ◽  
Indirect Methods ◽  
Operational Characteristics ◽  
Wide Range ◽  
Effective Operation ◽  
And Performance ◽  
Plant Simulation

AbstractIntra-plant transport systems within their operation directly impact on the performance of production systems. For their effective operation, it is, therefore, necessary to realize evaluation of operational performance and effectivity. For the realization of this type of evaluation, in addition to a wide range of sensors that can be difficult for installation and operation, we can also use indirect methods that are equally able to provide reliable operational characteristics. Indirect analytical methods are presented above all by the approach which is based on the use of simulation methods. The method of computer simulation provides a wide range of options for the evaluation of efficiency and performance. The paper describes the use of a simulation model created in the program Tecnomatix Plant Simulation for analyzing the supply of production workplaces within the MilkRun system.

Hider: A Methodology for Early-Stage Exploration of Design Space

1996 ◽  
Author(s):  
Sudhakar Y. Reddy
Keyword(s):  
Design Space ◽  
Optimization Problems ◽  
Early Stage ◽  
Simulation Models ◽  
Design Tool ◽  
System Level ◽  
Complex Simulation ◽  
Machine Learning Approach ◽  
Detailed Simulation ◽  
And Performance

Abstract This paper describes HIDER, a methodology that enables detailed simulation models to be used during the early stages of system design. HIDER uses a machine learning approach to form abstract models from the detailed models. The abstract models are used for multiple-objective optimization to obtain sets of non-dominated designs. The tradeoffs between design and performance attributes in the non-dominated sets are used to interactively refine the design space. A prototype design tool has been developed to assist the designer in easily forming abstract models, flexibly defining optimization problems, and interactively exploring and refining the design space. To demonstrate the practical applicability of this approach, the paper presents results from the application of HIDER to the system-level design of a wheel loader. In this demonstration, complex simulation models for cycle time evaluation and stability analysis are used together for early-stage exploration of design space.

Design of a cable-stayed footbridge adaptable to various urban areas

2019 ◽  
Author(s):  
Franco Clerici ◽  
Silvia Mirabella
Keyword(s):  
Public Transportation ◽  
Urban Areas ◽  
Local Governments ◽  
Open Spaces ◽  
Limited Space ◽  
Reduced Mobility

<p>The present paper relates to the design of a cable-stayed footbridge, composed by ready made elements and with span suitable to various urban and building areas. At present, in order to find a solution to traffic problems, local governments look for many ways to alleviate city’s main roads, increasing public transportation and designing dedicated underground pedestrian routes. Although this subways already built are not really used by pedestrians, which prefer wide-open spaces, such as skyways also designed for people with reduced mobility. In this context the described footbridge, with access ramps designed in accordance with accessibility standards, represents not only a good solution for cycle and pedestrian mobility problems, but it is also easy to transport and to be installed, due to its modular elements. The access ramps are suspended to pilons with inclination depending by the required bridge lengths and they can be assembled in different configurations in order to be well integrated also in limited space areas. Finally a particular focus is dedicated to cables, with dismountable end terminations designed to reduce transportation space and costs</p>

Design and Performance Analysis of Pedestrian Crossing Facilities for Continuous Flow Intersections

2005 ◽  
Vol 1939 (1) ◽  
pp. 133-144 ◽  
Author(s):  
Ramanujan Jagannathan ◽  
Joe G. Bared
Keyword(s):  
Continuous Flow ◽  
Level Of Service ◽  
Vehicular Traffic ◽  
Average Delay ◽  
Qualitative And Quantitative ◽  
Traffic Performance ◽  
Pedestrian Traffic ◽  
Pedestrian Level Of Service ◽  
And Performance ◽  
Pedestrian Crossing

Although concepts of the continuous flow intersection (CFI) have been around for approximately four decades, minimal or no literature describing studies that have analyzed pedestrian traffic performance at these intersections is available. Several studies have reported on the qualitative and quantitative benefits for the vehicular traffic performance of CFIs in comparison with the benefits for the vehicular traffic performance of conventional intersections but have provided minimal or no discussion about pedestrian traffic performance. As a novel intersection design, many important considerations are required to design pedestrian accesses and crossings at CFIs without compromising pedestrian safety and vehicular traffic performance. In this paper, the design methodologies for providing pedestrian access and related pedestrian signal timings are discussed. Modeling was conducted on three typical geometries for CFIs with base signal timings optimized for vehicular traffic performance. The results indicate an acceptable pedestrian level of service of B or C on the basis of the average delay per stop experienced by any pedestrian for pedestrian crossings at the typical CFI geometries modeled. All pedestrians served at the CFIs are accommodated within two cycles for a typical signal cycle length ranging from 60 to 100 s.

scholarly journals Rise-Up mist-netting (RUM): a mobile protocol for trapping wary territorial birds

2021 ◽  
Vol 61 ◽  
pp. e20216110
Author(s):  
Paulo Sérgio Amorim ◽  
Mariana Fonseca Rossi ◽  
André de Camargo Guaraldo
Keyword(s):  
Urban Area ◽  
Rural Areas ◽  
Urban Areas ◽  
General Public ◽  
Bird Species ◽  
Breeding Period ◽  
The Novel ◽  
Limited Space ◽  
Trapping Methods ◽  
Visual Impacts

Many bird species avoid traditional traps such as mist nets, thus alternative trapping methods are often needed. The Rufous Hornero (Furnariidae: Furnarius rufus) is one such species that was captured so far using conventional mist netting in rural areas or using nest-targeted traps, which risk nest damage and abandonment. Here we describe the novel rise-up mist-netting (RUM) protocol and its catchability for the wary and territorial Rufous Hornero in an urban area. The RUM trap allowed us quickly capturing 40 Rufous Hornero individuals even in paved parking lots and streets during the bird’s breeding period. The RUM is an active and targeted protocol that demands a single and quickly trainable field assistant. Therefore, it should also enable the capture of many understudied territorial but wary species. Moreover, it has enough mobility to fit studies in urban areas, and whenever researchers may deal with limited space and, at the same time, should reduce negative visual impacts to the general public of birds’ capturing and banding procedures.

The impact of future cities on commuting patterns: An agent-based approach

2018 ◽  
Vol 46 (6) ◽  
pp. 1079-1096
Author(s):  
Marcello Marini ◽  
Anna P Gawlikowska ◽  
Andrea Rossi ◽  
Ndaona Chokani ◽  
Hubert Klumpner ◽  
...  
Keyword(s):  
Urban Areas ◽  
Simulation Models ◽  
Single Family ◽  
Simulation Framework ◽  
Agent Based ◽  
Commercial Activities ◽  
Transportation Sector ◽  
Commuting Time ◽  
Commuting Patterns ◽  
The Impact

Over the next 35 years, the population of Switzerland is expected to grow by 25%. One possible way to accommodate this larger population is to transform smaller cities in Switzerland through the direct intervention of urban planners. In this work, we integrate agent-based simulation models of people flow, mobility and urban infrastructure with models of the electricity and gas systems to examine the increase of the density of existing residential zones and the creation of new workplaces and commercial activities in these urban areas. This novel simulation framework is used to assess, for the year 2050, two different scenarios of urbanization in a region with small urban areas. It is shown that a densification scenario, with a preference for multi-dwelling buildings, consumes 93% less land than a sprawl scenario, with a preference for single-family houses. The former scenario also accommodates 27% more people than the latter scenario, as there is a higher penetration of battery electric vehicles – and therefore reduced air pollution from the transportation sector – and also a larger shift of commuters to the use of public transport. However, in the former scenario, the commuting time is 20% longer. The outcome of this work demonstrates how this novel simulation framework can be used to support the formulation of policies that can direct the transformation of urban areas.

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