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181.
This paper presents the optimization of key component sizes and control strategy for parallel hybrid electric vehicles (parallel HEVs) using the bees algorithm (BA). The BA is an intelligent optimization tool that mimics the food foraging behavior of honey bees. Parallel HEV configuration and electric assist control strategy were used to conduct the research. The values of the key component size and the control strategy parameters were adjusted according to the BA to minimize the weighted sum of fuel consumption (FC) and emissions, while the vehicle performance satisfies the PNGV constraints. In this research, the software ADVISOR was used as the simulation tool, and the driving cycles FTP, ECE-EUDC and UDDS were employed to evaluate FC, emission and dynamic performance. The results demonstrate that the BA is a powerful tool in parallel HEV optimization to determine the optimal parameters of component sizes and control strategy, resulting in the improvement of FC and emissions without sacrificing vehicle performance. In addition, the BA is able to define a global solution with a high rate of convergence.  相似文献   
182.
The use of plastic in vehicle development has increased. In particular, a design trend has resulted in chromiumplated plastics being used in exterior panels. Recently, as the appearance has become more important in design, the plastic radiator grille has become larger, to where it can become the primary member when a front collision happens. The radiator grille should be designed with considerations of the geometric structure, such as delamination, and material characteristics, when plastics are plated with chromium. The enlarged grille has to pass regulations like FMVSS Part 581. Although the material property of plastic has been studied before, what seems to be lacking is study on the crashworthiness of plastic radiator grilles that are plated using chromium. In this paper, in order to evaluate the crashworthiness, tensile test and front collision analysis using finite element method are performed. Tensile test is conducted with 4 types of materials, and then material properties of chromium-plated plastics are obtained. Meanwhile radiator grille’s crashworthiness is evaluated using finite element analysis method. Analysis result is evaluated according to failure criterion. Through this study, method of the assessment of plastic radiator grille’s crashworthiness considered material properties of chromium plated plastics is proposed, and it can be predicted the delamination and the failure point of radiator grille at the design step.  相似文献   
183.
In this study we will estimate the region of attraction (RoA) of the lateral dynamics of a nonlinear single-track vehicle model. The tyre forces are approximated using rational functions that are shown to capture the nonlinearities of tyre curves significantly better than polynomial functions. An existing sum-of-squares (SOS) programming algorithm for estimating regions of attraction is extended to accommodate the use of rational vector fields. This algorithm is then used to find an estimate of the RoA of the vehicle lateral dynamics. The influence of vehicle parameters and driving conditions on the stability region are studied. It is shown that SOS programming techniques can be used to approximate the stability region without resorting to numerical integration. The RoA estimate from the SOS algorithm is compared to the existing results in the literature. The proposed method is shown to obtain significantly better RoA estimates.  相似文献   
184.
文章提出了一种新颖的采用模糊逻辑控制的异步电动机(IM)转速控制方法.模糊逻辑控制器(FLC)是基于间接矢量控制系统设计的.模糊逻辑转速控制器用于外层回路.针对实验室1 hp鼠笼式IM采用DS-1102数字信号处理器插件板,对基于FLC的IM矢量控制传动系统进行了实验研究.对文章提出的基于FLC的IM传动性能进行了研究,从理论和实验两个方面,在诸如指令转速突变、负载阶跃变化等不同的动态工作条件下,与基于传统的比例积分(PI)控制器的传动系统作了比较,结果表明使用FLC更优越.因此该方法适用于高性能工业传动系统,以取代传统PI控制器的方法.  相似文献   
185.
锰粉加工工人心血管功能的调查研究   总被引:1,自引:1,他引:1  
对 55 名锰粉加工工人和 56 名对照工人的调查结果显示,工人工作地点 Mn O2 浓度几何均值为 196 m g/m 3 (锰尘 017~22.24 m g/m 3 ),样品超标率 887% 。接触组头晕头痛、睡眠障碍、容易疲劳和记忆不良的主诉率明显高于对照组( P<005~001)。接触组和对照组的心电图异常、高血压和低舒张压检出率未见显著性差异,其心率、 P R间期、 Q R S波、收缩压和舒张压的均值比较也没有显著性差异。接触组心电图异常和低舒张压的 O R分别是 1.56(95% 可信区间为 070~3.50)和 2.08(95% 可信区间为 018~23.57)。  相似文献   
186.
We use linear programming (LP) for solving the problem of the optimal deployment of an existing fleet of multipurpose or fully containerized ships, among a given set of routes, including information for lay-up time, if any, and type and number of extra ships to charter, based on a detailed and realistic model for the calculation of the operating costs of all the ship types in every route and on a suitable LP formulation developed in earlier work of the authors. The optimization model is also applicable to the problem of finding the best fleet compostion and deployment, in a given set of trade routes, which may be the case when a shipping company is considering new or modified services, or a renewal of the existing fleet. In addition, two promising mixed linear-integer programming formulations are suggested.  相似文献   
187.
188.
This paper presents a calibration method of a rule-based energy management strategy designed for a plug-in hybrid electric vehicle, which aims to find the optimal set of control parameters to compromise within the conflicting calibration requirements (e.g. emissions and economy). A comprehensive evaluating indicator covering emissions and economy performance is constructed by the method of radar chart. Moreover, a radial basis functions (RBFs) neural network model is proposed to establish a precise model within the control parameters and the comprehensive evaluation indicator. The best set of control parameters under offline calibration is gained by the multi-island genetic algorithm. Finally, the offline calibration results are compared with the experimental results using a chassis dynamometer. The comparison results validate the effectiveness of the proposed offline calibrating approach, which is based on the radar chart method and the RBF neural network model on vehicle performance improvement and calibrating efficiency.  相似文献   
189.
In this feasibility study, we investigate the viability of using Liquefied Natural Gas (LNG) fuel in an open type Ro-Ro passenger ferry and the associated potential challenges with regard to the vessel safety systems. We recommend an appropriate methodology for converting existing ships to run on LNG fuel, discuss all the necessary modifications to the ship’s safety systems, and also evaluate the relevant ship evacuation procedures. We outline the basic requirements with which the ship already complies for each safety system and analyze the additional restrictions that must be taken into consideration for the use of LNG fuel. Appropriate actions are recommended. Furthermore, we carry out a hazard identification study. Overall, we clearly demonstrate the technical feasibility of the investigated scenario. Minimal modifications to the ship’s safety systems are required to comply with existing safety rules for this specific type of ship.  相似文献   
190.
The objective of the internal design of a transport terminal is to minimize the disorientation and confusion of a passenger as he arrives at the terminal and desires to move towards the destination without undue loss of time. The experience of India however shows that most of the rail, bus and air terminals leave much to be desired from the human orientation point of view. To measure the passenger orientation and to enable evaluation of the terminal design an easily tractable quantitative method has recently been evolved. This paper attempts to apply it to two rail terminals in Bombay and to compute some indices to serve as criteria for determining the level of service and suggest directions for improvement.  相似文献   
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