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36351.基于同步制造的决策支持仿真系统
[信息传输、软件和信息技术服务业,汽车制造业] [2014-07-24]
The focus of the article was the redesign of an assembly cell in a car manufacturing company. The new design had to include the operations related to the assembly of new roofs without disrupting the throughput rate. The theory-of-constrains framework has been used to propose designs as well as to define the evaluation criteria. The complexity of the system has been studied using a discrete-event simulation model. The traditional scholar steps have been followed to develop a robust decision support simulation system (DSSS).
关键词:汽车;决策支持系统;仿真;汽车系统
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36352.基于模型的运输绩效:比较框架和文献合成
[汽车制造业,信息传输、软件和信息技术服务业] [2014-07-24]
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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36353.多式联运一体化客运系统
[汽车制造业,信息传输、软件和信息技术服务业] [2014-07-24]
Modern transportation consists of many unique modes of travel. Each of these modes and their respective industries has evolved independently over time, forming a largely incoherent and inefficient overall transportation system. Travelers today are forced to spend unnecessary time and efforts planning a trip through varying modes of travel each with their own scheduling, pricing, and services; causing many travelers to simply rely on their relatively inefficient and expensive personal automobile. This paper presents a demonstration program system to not only collect and format many different sources of trip planning information, but also combine these independent modes of travel in order to form optimal routes and itineraries of travel. The results of this system show a mean decrease in inter-city travel time of 10 percent and a 25 percent reduction in carbon dioxide emissions over personal automobiles. Additionally, a 55 percent reduction in carbon dioxide emissions is observed for intra-city travel. A conclusion is that current resources are available, if somewhat hidden, to drastically improve point to point transportation in terms of time spent traveling, the cost of travel, and the ecological impact of a trip. Finally, future concepts are considered which could dramatically improve the interoperability and efficiency of the transportation infrastructure.
关键词:汽车;系统集成;航空运输;互操作性
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36354.基于脉冲信号的无线传输研究
[信息传输、软件和信息技术服务业] [2014-07-24]
The system uses dual MCU design to achieve the acquisition and transmission of pulse signal without affecting the user's sleeping process.The pulse signal is collected by infrared pulse sensor,and is wireless transferred to the personal computer by JF24C after the process of amplification,baseline correction and so on.Then personal computer analyses the signal using the method of wavelet transform algorithm.With wavelet decomposition,pulse signal can be decomposed into different scales of wavelet coefficients and recomposed according to the low-frequency coefficient of the bottom and high-frequency coefficients of various layers.During the process of wave recomposition,the coefficients related to noise can be rejected while the valuable information in the pulse signal maintained,and all the processes achieve the restoration of pulse signal.What is more,after simulating the wavelet transform algorithm using MATLAB,theconsequences of this simulation indicate that multiple interferences can be effectively suppressed while keeping the pulse signal undistorted and it sustains the relevant characteristics of pulse signal.
关键词:脉冲信号,无线传输;嵌入式系统;小波变换;MATLAB
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36355.基于计算机视觉的城市交通自动控制研究
[交通运输、仓储和邮政业,信息传输、软件和信息技术服务业] [2014-07-24]
Urban traffic control is not only a real-time control system but also random,non-line ar,uncertainty complex system; the article discusses the use of PLC (programmable logic controlle r) control technology and fuzzy control method for traffic signal control system and how to complete the complex traffic control by using communications link technology between comp uters and application of fuzzy control theory,make vehicle and road navigation to realize intelligent.
关键词:汽车;城市交通;自动控制;模糊控制;信号控制
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36356.不安全驾驶事件中车辆间的安全预警信息系统:方法和原型实现
[信息传输、软件和信息技术服务业] [2014-07-23]
Driver inattentiveness and distraction resulting in unsafe vehicle maneuvers are a significant safety concern because such behavior can directly lead to crashes. An effective technical countermeasure is to detect unsafe driving events and provide drivers with advanced warning information. This study presents an intervehicle safety warning information system. An inertial measurement unit consisting of an accelerometer and gyro sensor in addition to a Global Positioning System receiver was used to collect data for the developed algorithm. Vehicle position, speed, acceleration, and angular velocity data were analyzed and were used as inputs for the algorithm. A support vector machine classifier was also incorporated into the algorithm to identify further the severity of unsafe driving events. The performance evaluation results showed that the detection algorithm could capture longitudinal and transverse unsafe driving events. In addition, a prototype of the proposed warning information system was implemented on a test bed in support of vehicle-to-vehicle and vehicle-to-infrastructure communications. Extensive field tests have been conducted in the test bed to fine-tune the prototypical system. These results demonstrate that the system holds promise for improving drivers' safety and mitigating crash risks.
关键词:信息系统;预警监测;模型;实现
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36357.基于协调者节点的无线个域网网络隔离自愈研究
[信息传输、软件和信息技术服务业] [2014-07-23]
A single-chip solution is proposed to realize the node design based on 2.4 GHz Zig,Bee wireless sensor network.Mesh network topology is achieved by the use of ZigBec Pro protocol stack on the hardware platform.When the packets are successfully sent to the coordinator node,a relevant event will be generated by the local node.Hence,the parent node lost event can be obtained by comparing the number of the packets sent by the child node and the number of the packets sent successfully shown by the respond event.A wireless sensor network is designed to work independently from the coordinator node and can be re-connected according to the needed set to resume the network.When the coordinator node is taken away from the site or power down by happenstance and power up again after a long time,the parent lost event in the child nodes can make it rejoin the new coordinator node again when needed.The network self-healing function can be achieved by this mechanism that makes the network more stable.
关键词:JN5148;无线个域网;啮合;自愈网络
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36358.基于DAG移动下沉的无线传感器网络多路径路由协议
[信息传输、软件和信息技术服务业] [2014-07-23]
Low power and Iossy networks have been an active area of research.Numerous protocols have been proposed for routing in these networks using metrics like hop count,delay,bandwidth etc.The IETF ROLL group has proposed a proactive gradient protocol called RPL.However,for a network with few mobile sinks calculating gradients using proactive approach is not energy efficiency.This paper proposed a multipath routing protocol for Wireless Sensor Networks with mobile sinks,called MDMR.Directed Acyclic Graphs (DAGs) are required for WSNs organization because of their route redundancy to the root.MDMR is based on RPL framework.By broadcasting DAG construction messages including metrics,such as,hop count,node energy and link quality indication,protocol constructs DAG and provides path redundancy.This allows nodes to find multiple alternative paths easily while link failures.
关键词:无线传感器网络;多路径;路由协议;DAG;RPL
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36359.多受限的无线传感器网络的QoS路由算法
[信息传输、软件和信息技术服务业] [2014-07-23]
Routing problem is one of the most important issues to a wireless sensor network (WSN).It is the key problem to find an efficient energy strategy for prolonging network's lifetime because power supply might be impossible.This paper discusses the multicast routing problem of WSN with multiple QoS constraints,which may deal with the delay,bandwidth,hop count and packet reception rat and surplus energy metrics,and finds a minimum resource consumption path while satisfying multiple constraints optimization conditions,and describes a network model for researching the multicast routing problem.It presents a dynamic multicast routing algorithm with multiple QoS constraints (MCQoSRA).The MCQoSRA successfully solves the QoS routing problems when multicast nodes change dynamically in the networks.The MCQoSRA only requires the local state information of the link (or node),but does not require any global network sate to be maintained.In MCQoSRA,a multicast group member can join or leave the multicast session dynamically.The MCQoSRA can effectively decrease the overhead for constructing a multicast tree and the delay of the nodes,and improve the success ratio of seeking links.Simulation results show that the MCQoSRA provides an available means to implement muiticast routing,and adapt to all kinds of the topology networks,and have better expansibility.
关键词:传感器网络;QoS;多播路由;能量
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36360.电子商务-第028期
[信息传输、软件和信息技术服务业,交通运输、仓储和邮政业,批发和零售业] [2014-07-23]
报告包括电子商务方面的重要观点、政策与环境、网购平台、行业应用、电商物流、电商金融等研究。
关键词:政策环境;网购平台;电商物流;电商金融