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Vehicle and pedestrian safety impacts of signal timing optimization in a dense urban street network

Journal of Traffic and transportation Engineering(English Edition) 2016年第1期3卷 16-27页

作者： Arash M.Roshandeh Zongzhi Li shengrui Zhang herbert s.leuinson Xi Lu Department of Engineering and Public Works City of AlpharettaGA 30009USA Department of civil Architectural and Environmental Engineeringillinois Institute of TechnologyChicagoIL 60616USA school of Highway Chang'an UniuersityXi'an 710064China herbert s.leuinson transportation consultant New HauenCT 06492USA

Intersection signal timing optimization is expected to affect both traffic mobility and safety. However, in safety impacts analysis, the existing studies mainly focus on estimating changes in vehicle crashes without addressing the influence of pedestrian related crashes. This study aims to simultaneously assess the overall impacts of vehicle and pedestrian crashes caused by signal timing optimization in dense urban street networks. An empirical Bayesian analysis method was introduced to estimate the safety impacts of intersection signal timing optimization in an urban street network in terms of vehicle-tovehicle and vehicle-to-pedestrian crashes at intersections, as well as single and multiple vehicle crashes on street segments. A computational experiment was performed to apply the proposed method to the Chicago central business district that includes 875 signalized intersections and 2016 roadway segments. Results show that vehicle-to-vehicle and vehicle-to-pedestrian crashes at intersections are decreased in different crash severity levels and types, especially for angle and rear-end ones after signal timing optimization. similar results are found for multi-vehicle rear-end crashes on street segments. These indicate that intersection signal timing optimization in dense urban street networks has a potential for improving traffic mobility, vehicle and pedestrian safety at intersections, and vehicle safety on street segments.

关键词： signalOptimizationsafetyVehiclePedestrianEmpirical Bayesian analysis

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Ancient road transport devices： Developments from the Bronze Age to the Roman Empire

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Frontiers of Mechanical Engineering 2016年第1期11卷 12-25页

作者： Cesare ROssI Thomas G. CHONDROs Kypros F. MILIDONIs sergio sAVINO Flavio RUssO Department of Industrial Engineering University of Naples 'Federico II' Naples 80125 Italy Mechanical Engineering & Aeronautics Department University of Patras Patras 26500 Greece UssME consultant via Lamaria 137 Torte del Greco Napoli Italy

The development of transportation systems has significantly enhanced the welfare and modernization of society. Wooden vehicles pulled by animals have been used for land transportation since the early Bronze Age. Whole-body gharries with rigid wheels pulled by oxen appeared in Crete by 2000 BC or earlier. Horses originating from the East were depicted in early Cretan seal-rings of the same period. The two-wheeled horse- drawn chariot was one of the most important inventions in history. This vehicle provided humanity its first concept of personal transport and was the key technology of war for 2000 years. Chariots of Mycenaean and Archaic Greece with light and flexible four-spoked wheels acting as spring suspensions were depicted in vase paintings. The development of this vehicle incorporated the seeds of a primitive design activity and was important for engineering. The Trojan horse since 1194 BC and the helepolis since 700 BC were the first known machines on a wheeled base transported by horses or self-powered. Ancient engineers invented bearings lubricated with fat, and Romans introduced the ancestors of ball bearings for their wagons and carts. The historic evolution of wheeled transportation systems, along with early traction, suspension, and braking systems, is presented in this paper. Analytical and numerical methods are incorporated to analyze the most conceivable loading situations of typically reconstructed wheeled transportation systems in ancient times. Traction requirements both for horse-driven machines and the power for internal motors are also analyzed. This study can serve as a basis for further development of detailed reconstruction of transportation systems in antiquity.

关键词： transportation wheel spoke cart axle bearing

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Electric Buses in Urban Transport, The situation and Development Trends

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Journal of Traffic and transportation Engineering 2014年第1期2卷 45-58页

作者： Jakub slavlk self-employed business consultant Ri6any u Prahy 25101 Czech Republic

A study called ＂E-mobilita v MHD＂（e-mobility in urban mass transit） has been conducted by the author＇s private consultancy to inform Czech public transport operators about the technologies and operational experience to date and stimulate the e-bus utilization as well as their involvement in e-bus research and development projects. The study covers trolley-buses, diesel hybrids and e-buses including fuel cell buses. These electric urban buses have been compared with combustion engine vehicles represented by diesel and CNG （compressed natural gas） buses, in terms of energy consumption and cost, greenhouse gas emissions, noise and life cycle cost. Relations between urban transport e-mobility and the ＂smart grid＂ concept have been presented as well. Comprehensive reports prepared on the European Union and the UsA levels have been the basis for the study, completed by information from the field research, focused especially on the bus operational reliability and other parameters important for a transport operator and covering, interalia, 12 case studies. The results show electric buses as a promising urban transport mode with massive technology development overcoming their operational limitations. synergies between electric buses and other urban systems, such as power supply, are notable as well.

关键词： Electric bus, trolley-bus, fuel cell bus, charging, urban transport.

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Exploratory Methodology for Identification of Urban Bottlenecks Using GPs Data

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Journal of Traffic and transportation Engineering 2016年第5期4卷 280-290页

作者： Andres L. Jimenez Alvaro Rodriguez-Valencia Independent consultant Department of Civil and Environmental Engineering Universidad de los Andes Bogota 111711 Colombia

Bottlenecks have been widely studied for uninterrupted flow. The study of bottlenecks in urban traffic networks implies a challenge, since delays and queuing are implicit in interrupted flows. The objective of this paper is to discuss bottlenecks in urban traffic networks and present a methodology to identify them, based on GPs （Global Position system） data from taxis in Bogota Colombia. In networks, where stops are frequent, the principle we adopted deals with finding recurrent low-speed sections, beyond expected delays. Urban bottlenecks occur in those road network segments that perform poorly in terms of speed, compared with upstream and downstream conditions, producing recurrent and larger than normal delays. The GPs devices reported, via GPRs （General Packet Radio service）, information every 10 s. Results of this exploratory project are promising. The method allowed the identification of six urban bottlenecks out of seven randomly selected low-speed sections. The most valuable application of this methodology is the prioritization of resources investment in traffic infrastructure improvements. As a low cost option, this exploratory method might be especially attractive in identifying critical points in traffic networks in developing cities, without expensive traffic-monitoring systems.

关键词： Urban bottleneck bottleneck road network GPs congestion investment prioritization traffic performance.

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Measurements &Detection Techniques in Nanotechnology in Road Applications

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World Journal of Nano science and Engineering 2020年第3期10卷 37-50页

作者： Hebatalrahman A. Hebatalrahman saaid I. Zaki Dr. Eng consultant in Materials science Egypt strength and Testing of Materials Housing and Building National Research Center Cairo Egypt

In recent years, the world of science has started to produce advanced materials and technology in the nanoscale, which known as nanotechnology. The use of nanotechnology has become wide spread in all branches of science, one of the important branches is the field of transportation. The application of nanotechnology in pavements showed great promise and the potential to change commonly used materials, which makes transportation more efficient, smart looking, stronger and durable that all lead to the extension of their life cycle of the roads. so, there is an essential need to prepare advanced nanotechnology tools and detection systems contain very recent instruments needed for nanotechnology studies, since the physical, chemical and biological properties of the material at nanoscale differ in fundamental and valuable ways from that at normal scale. In this work the different techniques in measuring and detection techniques in nanotechnology will be discussed the method of operation and accuracy of each technique will be evaluated, the main applications of each technique in industrial and construction field will be evaluated.

关键词： Nanotechnology Detection Equipment’s Accuracy transportation Pavements Roads

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Primary Chondrosarcoma of the Mammary Gland of a spayed American Akita Bitch: A Case Report

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Open Journal of Veterinary Medicine 2012年第2期2卷 81-83页

作者： Frank herbert Comhaire Inge Matteeusen Hilde De Cock Dierenartsen Praktijk Healthy Paws De Pinte Belgium MedVet Inc. Antwerpen Belgium Private consultant Sint Martens-Latem Belgium

An eleven-year-old spayed American Akita bitch rapidly developed a mammary tumour which was surgically removed. The histological examination revealed the tumour to be a sarcoma that presented positive immunohistochemical staining against vimentin and protein s 100. There was no staining against pan-actin. Based on the histological aspect and the pattern of immunohistochemical staining the diagnosis of primary extraskeletal chondrosarcoma of the mammary gland was considered most probable. Two months later the patient was euthanized with recurrent local tumour and metastases in the lungs.

关键词： Chondrosarcoma Extraskeletal Akita Mammary Tumour

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