一种基于Android的AHRS上位机软件设计

<正>AHRS(Attitude and Heading Reference System)指航姿参考系统,能够为飞机提供准确可靠的横滚、俯仰以及航向等信息,广泛应用于车辆、无人机、云台、船舶、水下航行器、虚拟现实设备等需要三维姿态测量的产品中。AHRS设备通常由加速度传感器、陀螺仪以及磁力传感器等组成,测量出加速度、角速度以及磁场强度信息数据,在通过互补滤波器、卡尔曼滤波器等滤波算法对传感器数据进行处理,最终得到横滚、俯仰以及航向等信息。     

长江航运“GPS”技术正起步

桥区预报、航路调整、可航水深、航向以及航速……目前,随着长江电子航道图（2．0版）在渝投入试运行,长江航运电子地图替代传统纸质航行参考图的“数字航运”技术起步发展。安装长江电子航道图（2．0版）的船舶,如同安装了“GPS导航”的汽车一样,系统会实时监测长江“路况”随时提醒,为长江上的行轮提供准确的助航标志、水深数据、地物地貌等航行信息,设计最佳航线并保证其安全航行。     

船舶通信导航技术及发展趋势研究

船舶通信导航技术主要以船舶作为载体平台,以水上航行空间作为应用环境,全程服务于船舶所有航行操作任务,为船舶达到目的地服务。船舶通信导航技术涉及各种通信导航手段,例如航位推算、无线电信号发送接收、地图匹配、卫星定位、惯性解算等等,也包括它们之间的技术组合,实现了对船舶动态与位置的相关参数分析。本文分别探讨了船舶通信与导航技术,并分析了它的未来发展趋势。     

频率捕获效应在民航通信导航系统中的应用

随着民航通信导航设备技术的发展,双频系统中引入了捕获效应的理论,在此就捕获效应的应用做一下分析讨论.     

自适应卡尔曼滤波算法改进与仿真

为改善滤波器的动态性能,提高滤波器的跟踪能力,本文提出了自适应卡尔曼滤波算法,并对算法进行了几点改进,以QPS卫星导航系统为例,进行了仿真验证。结果表明,该算法切实可行,并且能有效提高导航定位精度。     

机场导航设备监控系统设计与实现

本文在综合分析机场常规导航设备信号体制的基础上,针对机场孚航设备监控系统的现实需求,介绍一种网络技术、数据传输与数据采集等技术相结合构成的导航设备监控系统设计方案。     

基于数据折叠的TDDM-BPSK信号同步捕获方法

卫星导航新体制下的TDDM调制方式的出现,提高了信号的跟踪精度,同时给同步捕获技术带来了巨大的挑战。针对TDDM信号的独有特点,采用双通道并行捕获,并将循环相关法与数据折叠技术相结合,提出一种基于数据折叠的TDDM-BPSK信号同步捕获方法。通过仿真测试,验证了该算法能够快速、有效地实现对TDDM-BPSK信号的同步捕获。     

科技驱动新兴市场发展导航与位置服务产业成为新热点

<正>近期,我国导航与位置服务产业已经成为互掘联网企业关注的新热点---2014年2月10日,阿里及巴巴集团发布消息,拟对位置地图厂商高德公司进行现金收购,交易涉及约11亿美元。之前,百高度集团成立了专门的"地图事业部",致力搭建术基于地图产品的生活服务平台,并于2013年收购主了人人网旗下的团购业务糯米网,推进在地图上北的线上线下结合(O2O)等业务。腾讯集团在站2014年1月全资收购了拥有甲级导航测绘资质的精科菱航睿空间信息技术有限公司,依托其数据,业加快街景数据的采集。互联网企业针对导航与位置服务产业的一系列并购行为,显示了这一新兴航     

基于小波变换的车牌图像融合技术研究

车牌识别系统在对车牌进行识别时,由于捕获到的车牌受到天气、光照等复杂因素的影响,车牌图像不是很清晰,为使系统能够准确的完成车牌识别,车牌图像增强的研究就显得至关重要。它提出了一种利用平滑滤波器、中值滤波器和Roberts边缘检测算子与小波融合技术进行混合图像增强的方法,通过matlab R2011a进行仿真实验,能够达到较好的图像增强效果。     

卫星导航引领物联网概念——访北京航空航天大学电子信息工程学院杨东凯教授

卫星导航是一种采用人造卫星对地面、海洋、空中和空间用户进行定位导航和授时的技术,当前已经在我国经济建设和社会发展中发挥了巨大的作用,并逐步成为国家战略性新兴产业。在推动卫星导航科技进步和应用的过程中,涌现了一批中青年骨干专家．北京航空航天大学的杨东凯教授就是其中的一位。     

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.