基于三级模糊控制器的智能交通系统

本文通过对交通路口信号控制的了解和思考,尝试提出一种基于模糊算法的交通灯控制系统。此系统以各通行相位的平均车队长度作为模糊输入,并设计了三级模糊控制器,通过模糊算法分配当前通行相位的通行时间及下一通行相位的初始绿灯时间。应用MATLAB中的模糊逻辑工具箱并对该系统进行仿真,从而得出结论。     

基于Multisim的交通灯控制器设计与仿真

本文以Multisim仿真软件为平台设计了交通灯控制电路,对电路的相关参数进行调整,并进行仿真和理论分析。仿真结果表明,设计的电路达到了预期要求。     

带红闪的数字交通灯系统设计及其Proteus仿真

汽车的普及,交通问题越来越被重视。十字路口的交通问题更是至关重要。文章介绍了一种基于数字电路的十字路口交通灯控制系统,并使用Proteus进行仿真,达到了交通灯的预期效果。该系统可实现交通灯的自动轮换、各时段倒计时的显示、黄灯亮时红灯闪烁;接入手动总开关,实现系统暂停,用于处理紧急交通事件。通过在Proteus中仿真,运行结果良好。     

基于PLC的十字路口交通灯智能控制系统设计

交通信号灯监控系统采用MCGS软件和西门子S7-200系列PLC设计,然后选用S7-200PLC进行系统主电路和辅助电路设计,同时利用MCGS软件进行系统梯形图程序编辑;MCGS作为监控平台,对交通灯系统的运行操作进行整体全面的监控,最后通过系统仿真调试,实现交通灯智能控制的相应功能。本论文基于PLC电气控制系统对交通信号灯的控制设计过程。     

交通灯控制系统在proteus软件中的设计与仿真

交通控制灯在缓解交通拥堵中有很大作用,交通控制灯可以用单片机对红绿灯、LED数码管显示等进行控制来实现,论述了通过AT89C51单片机对交通灯控制系统进行硬件设计、软件设计以及用Proteus软件对整个系统进行模拟仿真。     

交通信号灯智能控制系统设计及LabView仿真实现

设计了基于Labview的交通灯智能控制系统,实现红、绿、黄三种颜色灯的交替点亮、车辆通行模拟以及实时监测交通灯状态等功能。基于Labview的智能交通灯模拟仿真系统,无需硬件电路支持,整个程序框图采用分模块设计,不仅编程简单、灵活、可靠性高,而且成本低、具有良好的经济效益。为实现交通智能控制提供了一条新的途径。     

交通灯控制系统在proteus软件中的设计与仿真

交通控制灯在缓解交通拥堵中有很大作用,交通控制灯可以用单片机对红绿灯、LED数码管显示等进行控制来实现,论述了通过AT89C51单片机对交通灯控制系统进行硬件设计、软件设计以及用Proteus软件对整个系统进行模拟仿真。     

基于西门子PLC1200交通灯系统设计

随着我国社会的不断发展,交通灯系统得到了广泛应用,在交通灯系统设计过程中应用了西门子PLC编程设计技术,通过PLC编程不仅可以满足交通灯系统的各项设计要求,还可以有效的提高交通灯系统的自动控制能力和自动调节能力。目前我国交通管理部门对交通灯系统的设计要求主要体现在其必须具备稳定性、可靠性和长期有效性等方面,而通过PLC编程技术即可以根据交通管理部门对交通灯系统的具体设计要求进行合理的设计,又可以实现交通灯系统运行的自动化。基于此,本文通过分析交通灯控制系统的主要运行流程,探究以PLC1200为基础的交通灯系统具体的设计过程。     

用8031单片机进行城市交通灯控制

系统采用MSC-51系列单片机Intel8031和可编程并行I/O接口芯片8255A为中心器件来设计交通灯控制器,实现了能根据实际车流量通过8031芯片的P1口设置红、绿灯燃亮时间的功能;为了系统稳定可靠,采用了MAX629"看门狗"芯片,避免了系统因为死机而停止工作的情况发生;显示时间直接通过8255的PA、PB口输出;交通灯信号通过PC口输出;交通灯的点亮采用VT双向晶闸管来控制,直接采用220V交流电源驱动,系统实用性强、操作简单、扩展性强。     

基于PLC的交通灯控制系统

可编程控制器PLC因其结构紧凑,使用方便,具有很强的适应性等优点,在十字路口交通灯控制系统中广泛应用。本文选择西门子可编程控制器S7-200为控制器,其控制器指令丰富,可以接各种输出、输入扩充设备。本文介绍了交通灯的PLC控制系统的设计要求,给出了具体的I/O地址,系统的流程图设计。该PLC控制系统在对交通灯的控制中取得了良好的效果,完全满足本系统提出的控制要求,实现了十字路口交通灯控制系统的自动化。     

Students' Reactions to the Introduction of Videoconferencing for Classroom Instruction

This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors.     

Cooler temperatures inductive to locust outbreaks

Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007.     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction.     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies.     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means.     

Rough Justice: A Statistical Assessment of ICANN's Uniform Dispute Resolution Policy

Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP.     

Prevalence of soft neurological signs in Chinese people

Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.     

Monoculture Rubber Plantations Have Negative Ef ects on Controlling Splash Erosion

<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence     

Chinese Scientists Use Earth Observation Technologies to Study and Protect Wild Camels

<正>Chinese scientists plan to apply Earth Observation technologies to protect the critically endangered wild camels(Camelus ferus).With the help of remote sensing,satellite positioning,geographical information system and wireless sensors networks,they will be able to access the distribution and population of the wild camels and protect their habitats.The project will be carried out by the International Research Center for Wild Camel Conservation,which was jointly established earlier this year by the Institute of Remote Sensing and Digital Earth(RADI)of the Chinese     

More than Skin Deep – Understand Skin Biology by Means of Dermatogenomics

<正>The Paul Gerson Unna Research Group on Dermatogenomics was founded in October 2012 at the Partner Institute for Computational Biology.The ultimate goal of the group is to understand the biology of skin and skin appendages.