对文《R-循环分块矩阵求逆的快速傅里叶算法》的注记

指出了文《R-循环分块矩阵求逆的快速傅里叶算法》中的一个错误,并证明了n阶r-循环矩阵的m次方根矩阵中仍为r-循环矩阵的矩阵个数为m^n,进一步给出了求n阶r-循环矩阵的m次方根矩阵中仍为r-循环矩阵的矩阵的快速算法,若用FFT计算一个m次方根矩阵,其时间复杂性为O（nlog2n）;计算全部平方根矩阵的时间复杂性为O（nm^n）。同时,本文还给出了求r-循环矩阵主平方根矩阵的算法。     

逆H-循环矩阵的相关问题研究

循环矩阵和H-矩阵的研究都是当前矩阵理论和应用研究的热点,根据循环矩阵和H-矩阵的定义,给出了逆H-循环矩阵的定义,并在此基础上推导出了逆H-循环矩阵的一些特殊性质.     

蛋白质loop区域闭合数值方法分析与比较

针对蛋白质loop区域的闭合问题,比较分析了两种来源于机器人学的数值方法——循环坐标下降法（CCD）和雅可比矩阵方法,进行了实现并设计实验。在计算时间和闭合效率方面循环坐标下降法要明显优于雅可比矩阵方法,而雅可比矩阵方法则可以较平均地改变每一个二面角值。     

关于n阶(n1,n2)型二重(r1,r2)-循环矩阵求逆及相乘的计算方法

循环矩阵的求逆及相乘的算法，无论在理论上还是在实际应用中都具有非常重要的意义．本文不从计算Jordan标准形式或特征值出发，而是利用矩阵乘法及逆矩阵的一些简单性质，给出了n阶(n1，n2)型二重(r1,r2)-循环矩阵求逆、两个n阶(n1，n2)型二重(r1，r2)-循环矩阵相乘的直接计算方法，推广了已有的结果,这些算法已编到C 源代码在服务器上通过，验证了这些算法是稳定的有效的,若用快速富里叶变换(FFT)计算，这些算法的时间复杂性均为O(n1n2log2n1n2)。     

循环不变子空间的应用

在线性代数中,循环不变子空间是一类重要的不变子空间,它可以用来描述线性变换的Jordan型矩阵,本文就主要讨论循环不变子空间的一些性质,并且用其来证明出Jordan型矩阵的存在性及其结构,在最后作为循环不变子空间的性质,我们将给出可交换线性变换存在多项式表示的充要条件。     

面向过程的企业文化建设测评体系构建

基于PDCA循环理论,对企业文化建设的基本过程进行了研究.分析了建设过程中每个步骤的特点;建立了面向过程的企业文化建设评价指标体系;采用灰色统计方法建立测评矩阵,利用灰色关联度法确定评价指标的权重,并运用模糊综合评价方法对企业文化建设过程进行合理的评价.最后,通过实例验证了该测评体系的有效性和可行性.     

用matlab实现行列式和矩阵基本计算

本文介绍了行列式和矩阵的定义及基本计算,并给出了Matlab在行列式的计算和矩阵的线性运算中的应用。     

冗余度机械臂末端执行器误差补偿

基于雅克比矩阵的伪逆解,提出了一种补偿冗余度机械臂关节角从而达到补偿机械臂位姿误差的方法。利用雅克比矩阵的伪逆解计算关节角增量,通过循环算法把末端位姿误差控制在要求精度范围内。     

关于k-Fibonacci和k-Lucas数的置换因子循环矩阵的谱范数

给出了置换因子循环矩阵A=Percirc p(Fk,0,Fk,1,…Fk,n-1)和B=PercircP(Lk,0,Lk,1………Lk,n-1)的谱范数的上界与下界,得到了矩阵A与B的Kronecker积与Hadamard积的谱范数的一些界.     

自然界最基本循环和微生物农业

为解决当前农业和环境面临的难题,文章讨论了有机物质在植物、动物、土壤和微生物这4个系统中的运动,指出这些运动形成了两个稳定的基本循环,我们称之为自然界的最基本循环。近100多年来,人类忽视了微生物在有机物质的转化和循环过程中的重要作用,结果使微生物系统受到伤害,最基本循环遭到严重破坏,导致农业和环境出现了一系列严重问题。文章提出了恢复微生物系统和最基本循环的具体方案,希望通过发展微生物农业使中国农业走上高效、可持续发展的道路。     

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.     

Low doses of a red wine ingredient figh diabetes in mice

Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said.     

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.     

Molecular motor assembly of a biomimetic system

Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction.     

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