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151.
Windows CE操作系统在机车显示器上的应用研究 总被引:4,自引:1,他引:3
介绍Windows CE操作系统的特点,阐述了将嵌入式操作系统Windows CE应用在机车显示器上的整个开发过程,并对其应川结果进行了总结。 相似文献
152.
为了阐述20世纪除汽车机动性外,交通发展经历的最重要的进程——城市高速公路的出现,考察了过去100年来美国城市交通规划的历史。通过回顾各种研究资料,认为资助州际公路发展所采用的方法使联邦和州公路工程师成为主管,这影响了公路的选线及设计。联邦公路工程师只关注机动车通过效率的最大化,而在很大程度上忽略了城市的其他利害关系。没有先进的规划理念指导、过度建设、稀疏、放射环状的道路网对于加强机动性取得了极大的效益,但通常要为此付出巨大的社会和环境成本。最后指出,在实践中要重新审视具有百年历史的协调交通与土地利用规划的观点,而且,公共财政权宜之计式的政治决策方式将对工程、出行和城市形态产生深远的影响。· 相似文献
153.
D. Danardono K. S. Kim E. Roziboyev C. U. Kim 《International Journal of Automotive Technology》2010,11(3):323-330
A roller vane type liquefied petroleum gas (LPG) pump was developed for a liquid phase LPG injection (LPLi) engine. Most of
the LPG pumps used in the current LPLi engines are installed inside of the LPG tank, but this pump is intended to be installed
outside of the LPG tank to overcome the difficulty of fixing an in-tank pump. Because LPG has a low boiling point and high
vapor pressure, it usually causes cavitation in the pump and consequently deteriorates the flow rate of the pump. The purpose
of this work is to optimize the design of the roller vane pump in order to suppress cavitation and increase the fuel flow
rate by using a computational fluid dynamics (CFD) analysis. In order to achieve these goals, the intake port configuration
and the rotor of the roller vane pump were redesigned and simulated using STAR-CD code. Computation was performed for six
different models to obtain the optimized design of the roller vane pump at a constant speed of 2600 rpm and a constant pressure
difference between the inlet and outlet of 5 bar. The computation results show that an increased intake port cross-section
area can suppress cavitation, and the pump can achieve a higher flow rate when the rotor configuration is changed to increase
its chamber volume. When the inlet pressure difference is 0.1 bar higher than the fluid saturation pressure, the pump reaches
its maximum flow rate. 相似文献
154.
A speed control algorithm for an ACC (Adaptive Cruise Control) system for curved roads is proposed based on driver behavior characteristics. As the foundation of this research, a driver speed model for curved roads is developed using a series of experimental data regarding driver behavior. To adapt the model to each driver’s individual curve speed behavior, the coefficients of the model are identified in real time from the data sequences collected during drivers’ manual operation stage by a self-learning algorithm based on a Recursive Least-Square (RLS) method with a forgetting factor. Using this algorithm, the parameters of the driver model can be identified from the data collected in the manual operation phase, and the identification results are applied during the ACC automatic control phase. Based on the developed model, the ACC speed control algorithm is modified to provide each individual driver with a customized speed profile for the scenario of a curved road with no car ahead. Tests verify the applicability of the modified system. 相似文献
155.
H. S. Seo B. C. Kim P. S. Park C. D. Lee S. S. Lee 《International Journal of Automotive Technology》2013,14(1):91-99
In this paper, we propose a universal plug and play (UPnP) — controller area network (CAN) gateway system using UPnP middleware for interoperability between external smart devices and an in-vehicle network. The proposed gateway consists of a UPnP communication device, a CAN communication device, and a device translator layer. In-vehicle devices are not usually IP-based, so we implemented an in-vehicle device manager in the UPnP communication device which is in the gateway. We developed a vehicle simulator to produce real vehicular data for performance analysis. The CAN communication device transmits and receives real-time vehicle data between the real vehicular simulator and external devices through the UPnP. The device translator layer configures a message frame for enabling seamless data input and output between the CAN and UPnP protocols. After implementation, we generated an internal-external service request and tested the result. Finally, we confirmed the service request and operation between external devices and the internal vehicular device. Additionally, for a variety of external device numbers and communication environments, we demonstrated the gateway performance by measuring the round trip time (RTT) for overall service implementation. 相似文献
156.
157.
158.
Synergies between Adjacent Beach-Nourishing Communities in a Morpho-Economic Coupled Coastline Model
Beach “nourishment” consists of placing sand on an eroding beach. The widened beach provides increased storm protection to adjacent structures and improved recreational benefits, but is most often transient, requiring on-going, repeated nourishment episodes. Numerical models of beach nourishment typically address such questions as how long a widened beach will last; economic models compare the benefits and costs of preserving a stretch of beach without regard to its geomorphic evolution. Neither have addressed the physical nor economic interactions between adjacent nourishing communities. Here, we couple a numerical model of coastline evolution and a cost-benefit model of beach nourishment, allowing adjacent communities to make dynamic nourishment decisions. Beach nourishment benefits adjacent communities both “updrift” and “downdrift.” The total amount of money spent on nourishment activities can decrease by as much as 25% when adjacent communities both conduct on-going nourishment projects, as opposed to the case where each community nourishes in isolation. 相似文献
159.
Motor vehicle crashes continue to result in large numbers of fatalities each year and represent the leading cause of death for young persons. In 2006, for example, there were over 42,700 fatalities associated with these crashes. Understanding the causes of these crashes and methods to reduce them continues to be of great interest to economists, public health officials, and policy makers. We present in this paper statistical models using a rich set of panel data covering the period 1980 to 2007 by state and the District of Columbia. Our choice of variables is based on an extensive literature highlighting the importance of policy, safety, demographic, and economic determinants of fatality rates. 相似文献
160.
This article presents the results of a three-year effort at applying information technology to the problem of collaborative natural resource management in San Diego Bay. As such, it represents an approach to integrated coastal zone management (ICZM). This effort resulted from a collaboration between the San Diego Supercomputer Center at the University of California, San Diego and the San Diego Bay Interagency Water Quality Panel for the purpose of (1) developing an environmental data repository to facilitate the acquisition and sharing of data and (2) the development of a visual model of the bay in support of the development of a comprehensive, coordinated management plan for San Diego Bay. It was determined from this study that information technology is an important and key component to ICZM but that sociopolitical factors may override the benefits of decision-support systems and should be considered at the outset of any project of this kind. 相似文献