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811.
J. Kim 《International Journal of Automotive Technology》2016,17(2):319-326
In this paper, the optimal power distribution of the front and rear motors for minimizing energy consumption of a 4WD EV is investigated. An optimal power distribution control is developed based on the mathematical energy consumption model of an EV. The objective function is defined while ignoring time. And, the time effect is applied by considering the objective function for every single driving point which consists of the vehicle driving force and velocity. From the optimization problem, the optimal torque distribution maps of the front and rear motors can be obtained for all vehicle driving force and velocity ranges. These maps can be expressed using a 3-dimensional map. If the vehicle driving force and velocity are determined, the optimal front and rear motor torques can be determined using these maps. These maps can distribute the front and rear motor torques for the entire velocity range. Thus, these maps can perform the optimal power (torque times speed) distribution of the front and rear motors for minimizing the energy consumption of the 4WD EV. The performance of the optimal power distribution is evaluated by comparing the energy consumption to that of simple power distribution control. For obtaining the energy consumption, a vehicle driving simulation is performed. For the simulation, the driving cycle is required, and the NEDC (New European Driving Cycle) is used. From the simulation results, it is found that the energy consumption of simple power distribution is 4.8 % larger than the optimal one. Thus, the optimal power distribution can minimize the 4WD EV energy consumption as the optimization objective function. 相似文献
812.
J. Kim 《International Journal of Automotive Technology》2016,17(6):977-982
This paper describes the design and shifting dynamics of a novel and small-sized transmission which composed of three epicyclic gear modules and a hub shaft in conjunction with several clutches. The proposed epicyclic gear train can be used in a personal mobility vehicle such as an electric utility vehicle and small car, etc. And it is distinguished from others for its small size, light weight, high efficiency, and wide speed range up to 18 gear steps. In this paper, its dynamic behavior is dealt with in order to ensure the automatic and robust shifts according to the shift commands, focused on the shift mechanism design. First the overall structure and operating principles of the transmission are described in detail. Based on the CAD data of whole components, a detailed multibody dynamic model is built using ADAMS software which can analyze the dynamic behavior of a mechanical system. Then numerical simulations are performed during the shift and whole operating period. From the simulation and experiment results, the overall performance and operating principles of the 18 speed epicyclic transmission are discussed and the design of shift device is optimized to ensure the robust shift finally. 相似文献
813.
F. Soriano M. Moreno-Eguilaz J. Alvarez J. Riera 《International Journal of Automotive Technology》2016,17(5):883-894
In this two-part paper, a topological analysis of powertrains for refuse-collecting vehicles (RCVs) based on simulation of different architectures (internal combustion engine, hybrid electric, and hybrid hydraulic) on real routes is proposed. In this second part, three different hybrid electric powertrain architectures are proposed and modeled. These architectures are based on the use of fuel cells, ultracapacitors, and batteries. A calculation engine, which is specifically designed to estimate energy consumption, respecting the original performance as the original internal combustion engine (ICE), is presented and used for simulations and component sizing. Finally, the overall performance of the different architectures (hybrid hydraulic, taken from the first paper part, and hybrid electric, estimated in this second part) and control strategies are summarized in a fuel and energy consumption table. Based on this table, an analysis of the different architecture performance results is carried out. From this analysis, a technological evolution of these vehicles in the medium- and long terms is proposed. 相似文献
814.
J. M. Hills D. Alcock T. Higham H. Kirkman M. Le Tissier C. Pagdilao 《Coastal management》2013,41(3):323-337
Development of awareness and capacity is a central component to the delivery of ICM and spans from local communities to national-level politicians. Education and training activities associated with ICM must be extremely varied to match both the existing capacity and role that the stakeholders play within the process of ICM. Consequently, there cannot be considered any effective “generic” ICM training; training must be tailored to match the requirements of target groups. The transfer and uptake of good-practice thus becomes an important aspect of quality enhancement in ICM capacity development. Six case studies from the Asia-Pacific region are presented that show diverse and innovative examples of good practice. A comparative analysis of these case studies is carried out in terms of institutional level of impact. In addition a generic systems-based evaluation framework is used to determine the extent to which the training impacts upon ICM implementation indicators. It is concluded that the exchange, transfer, and translation to local conditions of appropriate good practice in ICM capacity development can be an important element in enhancing the impact of ICM programs on the coastal environments and societies. Furthermore, there appears to be a positive link between the involvement of national/state/regional stakeholders in capacity-building initiatives and impacting a wider variety of indicators of ICM delivery. 相似文献
815.
Coastal management information is frequently communicated to stakeholders and the public through complicated management documents and engineering plans. With the recognition that public involvement in coastal decision-making processes should be widened have come calls to develop new techniques to communicate complicated coastal information. Using Virtual Reality Geographical Information Systems and visualization packages, such information may be presented using formats more suitable for public consultation and information dissemination exercises than those currently employed. Using a site on the north Norfolk coast of England, an integrated Geographical Information Systems based methodology is presented that allows the visualization of proposed coastal management interventions. Visualizations have been produced that can be published in traditional paper-based management documents, or electronically. The different visualizations are compared and the technical issues surrounding their use discussed. It is argued that the methodology has clear advantages over traditional communication methods, although further research is necessary to determine how it may be practically employed by coastal managers. 相似文献
816.
Thomas J. Simmers 《中国远洋航务》2006,(12):40-41
在航运物流链中,所有的货物都要经由海运码头。不管海铁联运,还是海运-卡车联运,或是海上转运,码头都是货物运输的中转站。海运码头运营商(以下简称为MTO)的运营对货物运输影响巨大。 相似文献
817.
J. D. Griffiths 《Maritime Policy and Management》2013,40(4):237-243
In this paper a project undertaken by the author is described to illustrate modifications which may be necessary to the type of analysis given in an earlier paper [1] when difficulties arise from various practical considerations. The problem examined deals with the installation of unloading facilities at a purpose-built iron ore terminal at a steelworks. However, some of the data quoted has been coded to preserve confidentiality. The project was bedevilled by an unusual number of uncertainties; to appreciate these it is necessary to view them in relation to the situation existing at that time. 相似文献
818.
George J. Busenberg 《Coastal management》2013,41(2-3):239-253
This study compares the contributions to policy change made by two Regional Citizens’ Advisory Councils that participate in the environmental management of the marine oil trade in coastal regions of Alaska. Both councils are remarkably well-funded and long-enduring examples of citizen participation in environmental policy. This study finds that both councils have applied their substantial funding resources to make significant contributions to policy change (policy contributions) in the marine oil trade of coastal Alaska. This study also finds that both councils have greatly magnified their policy contributions through collaborative efforts with many other organizations active in the marine oil trade of Alaska. Therefore, the overall policy contributions of the councils result from the joint application of council resources and collaborative efforts. 相似文献
819.
J. Alfred Steers 《Coastal management》2013,41(1-2):7-24
Abstract This article outlines the steps that have been taken to conserve the coast of Great Britain. It treats the subject historically and emphasizes the ways in which unofficial and official bodies have interacted. Apart from a few very restricted areas, the shoreline is open to all people. The siting of houses, chalets, and huts is strictly controlled. Problems arise from time to time as to the location of nuclear stations, oil storage areas, and similar installations; these issues are settled in full discussions at official inquiries at which all interests—official, business, and conservation–are represented. 相似文献
820.