Current Issue : January - March Volume : 2014 Issue Number : 1 Articles : 4 Articles
Purpose The paper concerns a transport system for pedestrian\r\nareas, based on a fleet of fully-automated Personal Intelligent\r\nAccessible Vehicles. The following services are provided:\r\ninstant access, open ended reservation and one way trips. All\r\nthese features provide users with high flexibility, but create a\r\nproblemof uneven distribution of vehicles among the stations.\r\nA fully vehicle based relocation strategy is proposed: when a\r\nrelocation is required vehicles automatically move among\r\nstations. The paper focuses on a methodology that allows to\r\nplan the proposed transport system for wide pedestrian areas.\r\nThe methodology aims to determine the fleet dimension and\r\nthe relocation strategy parameters which minimize the system\r\ncost. The system cost takes into account the level of service\r\nand the efficiency. Relocation strategy parameters define\r\nwhen and among which stations relocations should be\r\nperformed.\r\nMethods The problem faced is an optimisation problem\r\nwhere the search space is defined by all the possible fleet\r\ndimensions and relocation strategy parameters. As this cost\r\nfunction could be a multipeak function and since the search\r\nspace is discrete and extremely large, a random search algorithm\r\nhas been adopted. Because of the characteristics of the\r\nproblem, a parallel optimization techniquewas required.Given\r\na fleet dimension and relocation strategy parameters, a\r\nmicrosimulator models the activity of each user, as well as\r\nthe activity of each vehicle over time with the aim of finding\r\nthe level of service and the system efficiency.\r\nResults, conclusions and application The methodology has\r\nbeen applied to planning the proposed transport system for the\r\ncentre of Barreiro, Portugal...
Biodiesel has attracted a great deal attention recently as an alternative fuel due\r\nto increasing fuel prices and the imperative to reduce emissions. Among a wide range of\r\nbiodiesel resources, microalgae are a promising alternative fuel source because of the high\r\nbiomass, lipid productivity and environmentally friendliness. Microalgae is also a non-edible\r\nfood, therefore, there will be no impact on the human food supply chain. In this work,\r\npetroleum diesel (PD) and biodiesel from the microalgae Chlorella protothecoides\r\n(MCP-B20) blend have been used to examine the performance and the emission of a\r\n25.8 kW agriculture tractor engine. Two engine speeds at maximum power take off (PTO)\r\npower and torque have been selected for analysis using analysis of variance (ANOVA).\r\nThe results showed that there is no significant difference between the engine performance\r\nwhen microalgae biodiesel blend (MCP-B20) and PD were used. However, a significant\r\nreduction in CO, CO2 and NO emissions was found when MCP-B20 was used. These\r\noutcomes give strong indication that microalgae can be successfully used in tractors as\r\nalternative fuel....
This paper presents an experimental investigation\r\nof human control of vehicles carried out on the basis of\r\ngeneral theories on human movement. The longitudinal and\r\nlateral accelerations are studied, and their relations with theories\r\nof motor optimality principles, such as minimum jerk,\r\nminimum variance, and the two-thirds power law are\r\nhighlighted. Data have been collected during the final experimental\r\nphase of the EU interactIVe project, in which a vehicle\r\ndeveloped by Centro Ricerche Fiat has been used to demonstrate\r\ndriver continuous support produced by an artificial codriver,\r\nwithin a shared initiative framework. 24 subjects drove\r\nthe vehicle on a test route twice: once with the system active,\r\nthe other with the system silent. The test route is composed of\r\nurban arterials, extra urban and motorway roads, and takes\r\napproximately 40ââ?¬â??45 min to be driven. The total database thus\r\namounts to ~35 h of driving data recordings, for a total of\r\n~1.2 M samples per signal. Statistical summary data are\r\npresented, which describe human preferred accelerations, correlation\r\nbetween acceleration, curvature, and speed, and between\r\nlongitudinal and lateral acceleration. Different driving\r\nmodalities, corresponding to different motor strategies and\r\nprimitives, are revealed. Comparisons with literature data are\r\nalso made and discussed. The summary statistics may be\r\nuseful for the design of future ADAS systems, and indeed\r\nthey have been collected for the final tuning of the interactIVe\r\nco-driver....
Purpose The increasing importance of the Bus Rapid Transit\r\nsystems in the last 20 years has given rise to the implementation\r\nof several sorts of systems over the world with different\r\ncharacteristics and success levels.\r\nThis paper aims to describe a global approach of them as\r\nwell as to carry out an effective comparison in order to achieve\r\noutstanding conclusions.\r\nMethods From the conceptualization or determination of the\r\nmain features and evolution of BRT Systems we do a qualitative\r\nand quantitative analysis of the currently operating\r\nsystems according to the development of countries in which\r\nthey operate in order to identify the key factors for the success\r\nof such type of transportation, regarding both its management\r\nand users comfort.\r\nResults and conclusions Comparison between different BRT\r\nsystems according to their geographical area provides some\r\nimportant evidences. Paper results suggest that we can find\r\ntwo separate groups in BRT systems, on one hand, some\r\ncountries with more technology and commercial velocity\r\n(European, Australian and Americans BRT systems), and on\r\nthe other hand countries more developed in terms of service,\r\nridership, routes and impact in population. It�s necessary to\r\nunderstand the BRT in the context of the mobility of the city\r\nand as long as this system has to compete with other modes of\r\ntransport the compliance of desirable requirements for a full\r\nBRT become more essential....
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