Traditionally there has been a distinction between Combinatorial Solid Geometry (CSG) modeling systems and Sculptured Surface Design modeling systems. CSG modeling systems largely model parts which are unsculptured and consist of combinations of common shapes like spheres, prisms, ellipsoids, and the like. These shapes are represented as planar half spaces, and algebraic quadratic surfaces. The boolean combination of these surfaces is usually performed by ray-tracing. Sculptured Surface Design concerns itself with modeling the surface of an object, i.e., the boundaries of an object like an aircraft, a ship, or an automobile. The boundaries are represented by using parametric tensor-product surfaces consisting of Bezier curves and Nonuniform Rational B-spline Surfaces (NURBS). There are many times however, when both modeling approaches are needed. In particular it is often desirable to introduce free-form surfaces into the CSG system. Recent advances in ray- tracing free-form surfaces have allowed the integration of free-form objects in CSG systems. This presentation will discuss the development and integration of NURBS into the Ballistics Research Laboratory CSG modeling system.

关键词：汽车；计算机图形几何；模型；光线跟踪

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This report discusses light-vehicle crash countermeasure profiles and functions for five target pre-crash scenario groups based on vehicle-to-vehicle (V2V) communications. Target pre-crash scenario groups include rear-end, lane change, opposite direction, junction crossing, and left turn across path from opposite direction (LTAP/OD) crashes involving at least one light vehicle (e.g., passenger car, van, minivan, sport utility vehicle, or light pickup truck with a gross vehicle weight rating of 10,000 pounds or less). There are 10 pre-crash scenarios in these groups to be addressed by V2V-based crash countermeasures. Kinematic equations are presented for the time-to-collision and avoidance maneuvers to identify information needs for these crash countermeasures. Information needs are translated into countermeasure functional requirements based on relevant safety applications devised in two prior research projects dealing with cooperative V2V communications and autonomous vehicle-based sensing systems. This report identifies two target pre-crash scenarios that would require new safety applications not developed in prior projects, including the LTAP/OD and opposite direction/no vehicle maneuver pre-crash scenarios.

关键词：汽车；避免撞车；车辆安全；通信系统

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Automobile information on internet increases fast as the quick development in automobile information construction.However,general search engines are unable to meet the increasing demand for accurate searching of automobile information.The present paper reports the designing and implementation of a vertical search engine of automobile information by adopting vector space model to identify the automobile subject,and combine content analysis and link analysis.This search engine was proven making the result more reasonable and effective and thus increasing the rate of accuracy of search engine.

关键词：汽车；垂直搜索引擎；汽车资讯；主体识别

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Alternative fuels have the potential to provide significant economic and environmental benefits to airports and their communities. These fuels can lead to improvements in local air quality emissions and reductions in life-cycle greenhouse gases. In addition, alternative fuels offer the possibility to diversify away from imported conventional petroleum-derived fuels and enhance energy security. Furthermore, alternative fuel distribution programs offer airports additional business opportunities to generate revenue through the operation of such facilities or leasing of land to third-party operators. Airports are natural nodes for multi-modal demand and are ideally situated to become distribution centers for a variety of alternative fuels for aircraft and surface transportation. Producers and marketers of alternative fuels can take advantage of this concentrated demand to strengthen their business case as they can cater to a wide spectrum of potential clients, including airlines, airports, and third-party operators such as rental car facilities, courtesy shuttles, taxis, buses, freight trucks, and other fleets that may operate nearby. This is especially the case for facilities that produce alternative jet fuel because, in addition to jet fuel, they also produce co-products such as green diesel, which can be used by some passenger and most cargo vehicles.

关键词：汽车；燃料；替代品；空气质量；航空器

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Simulation model of automobile power train has been built using ADVISOR,on the basis of Genetic Algorithm Tool Box,the paper takes a mini car as example to carry out performance simulation calculation and power train parametric optimization design.The result show that automobile power performance and fuel economy and emission performance have been greatly improved The power train has great influence on automobile power performance and fuel economy and emission performance.It is an important approach to optimize its matching parameters on reducing the fuel wastage,improving dynamical performance and decreasing the emission of waste gas.Genetic Algorithm is kind of global searching and optimized algorithm which integrates the principles of biological evolution with optimization technology and computer technology.ADVISOR,advanced simulation software,was developed on the basis of MATLAB/Simulink and can rapidly analyze automobile power performance,fuel economy and emission performance.It is a better approach to cope with automobile power train match optimization by integrating ADVISOR's accurate simulation with Genetic Algorithtn's searching optimization with high efficiency.

关键词：汽车;顾问;汽车动力系统;多目标优化

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VisLab has been pioneering the world of autonomous driving since its early years; in 1998 VisLab organized one of the most innovative experiments for that period: a passenger car was equipped with sensing and actuation devices and was tested with autonomous steering along a 2000+ km on Italian highways

关键词：汽车；自主驾驶；传感和驱动装置；VisLab

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In an era of limited resources and a proliferation of data, there is increasing pressure to conduct careful evaluations of the economic, environmental, and equity effects of investments and policies that influence transportation and land-use systems. This report compares performance measures recommended to achieve desired goals and reviews the literature to determine the degree to which these measures have been implemented and what they indicate about the relative effectiveness of land-use, transit, and automobile pricing policies. Despite the variation in methods and performance measures implemented in the studies reviewed for this report, the synthesis of study results suggests the direction and relative magnitude of change resulting from different types of policies, as well as potential biases introduced by omitting the representation of the land-use and transportation interaction. Overall, the performance measures indicate that carefully designed transit, land-use, and automobile pricing policies may improve travel, economic, environmental, and equity conditions for communities. However, transit and peak-period automobile pricing policies can, in some situations, lead to negative performance outcomes across some or all measures, as illustrated in studies that explicitly represent the land-use and transportation interaction.

关键词：汽车；城市交通政策；尾气排放量；氮氧化物；一氧化碳

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The Energy & Environmental Research Center (EERC) has developed a high-pressure hydrogen production system that reforms a liquid organic feedstock and water at operating pressures up to 800 bar (approx. 12,000 psig). The advantages of this system include the elimination of energy-intensive hydrogen compression, a smaller process footprint, and the elimination of gaseous or liquid hydrogen transport. This system could also potentially enable distributed hydrogen production from centralized coal. Processes have been investigated to gasify coal and then convert the syngas into alcohol or alkanes. These alcohols and alkanes could then be easily transported in bulk to distributed high-pressure water-reforming (HPWR)-based systems to deliver hydrogen economically. The intent of this activity was to utilize the EERC's existing HPWR hydrogen production process, previously designed and constructed in a prior project phase, as a basis to improve operational and production performance of an existing demonstration unit. Parameters to be pursued included higher hydrogen delivery pressure, higher hydrogen production rates, and the ability to refill within a 5-minute time frame.

关键词：制氢；燃料电池；汽车；醇类；烷烃

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Compressed natural gas (CNG) automobile is an emerging new energy car.How to control gas injection is the key technology of CNG electronic control system.At present,the control based on the MAP graph is used usually,but this control method has some shortages,for example larger data,poor adaptive capacity and difficulties in data updating.BP neural network control has adaptive and self-learning,nonlinear processing ability and high generalization,and faults tolerant ability in processing information.In this paper,BP neural network is used to control natural gas injection in order to solve the shortage of the MAP picture control.Simulation experiment shows thefeasibility and advantage of this method.

关键词：压缩天然气汽车;注气; BP神经网络; MATLAB仿真

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The current scarcity of public charging infrastructure is one of the major barriers to mass household adoption of plug-in electric vehicles (PEVs). Although most PEV drivers can recharge their vehicles at home, the limited driving range of the vehicles restricts their usefulness for long-distance travel. In this paper, an agent-based information system is presented for identifying patterns in residential PEV ownership and driving activities to enable strategic deployment of new charging infrastructure. Driver agents consider their own driving activities within the simulated environment, in addition to the presence of charging stations and the vehicle ownership of others in their social network, when purchasing a new vehicle. Aside from conventional vehicles, drivers may select among multiple electric alternatives, including two PEV options. The Chicagoland area is used as a case study to demonstrate the different deployment scenarios are analyzed.

关键词：电动车;电动收费;信息系统;机动车驾驶

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