由IP电话发展看技术创新对垄断产业市场结构的冲击

技术创新使得高昂的传统电信网络建设成本不再成为电信市场竞争的必要条件，IP电话网络改变了电信企业在其市场份额相对较低时的技术成本结构，可以说技术创新突破了原来产业垄断的“结构性进入壁垒”，带来了新的市场和产业机会，并且成为改变电信产业市场结构和电信体制改革的重要动因。     

突破垄断VoIP的商业模式

2007年8月14日，“创富志”在北京举办了“创富志论坛——VoIP的商业模式”。VoIP简单说就是用因特网，或者用因特网和电话网共同传递语音，它打破本地电信运营商的垄断，极大地降低了通话成本，迅速风靡世界。我们熟悉的IP电话、话吧、Skype Out和上网语聊，都是VoIP的应用。[第一段]     

大学生人际交往心理成本调查

社会交换理论认为人际关系的重要影响因素是付出与收益之间的比较，付出的成本是无形的心理因素时即为心理成本。大学生这个群体的特殊性决定了其心理成本具有其独特特点。本文旨从大学生心理成本投入和产出的关系和功利性分析两方面对大学生人际交往中心理成本的投入动机进行分析，以期能进一步了解大学生人际交往特点和影响因素。     

对“利用Adobe Acrobat Professional8.O软件实现图片型PDF文件到文本型PDF文件的转换”一文的质疑——与李宗红老师商榷

对“利用Adobe Acrobat Professional 8.0软件实现图片型PDF文件到文本型PDF文件的转换”一文中概念笼统和认识片面的内容提出质疑并与该文作者商榷.基于计算机理论知识分析和对各种转换方法的比较,对“图片型”和“文本型”PDF文件的定义与区分、Adobe Acrobat法转换所得PDF文件的特点和注释标记问题以及Fineprint/PDFfactory转换法的不足进行了分析评述,并综合转换效率、转换质量和投入成本等因素,认为GSview法为目前书版PS文件转PDF的最经济、效率最高、转换质量较好的方法.     

新旧动能转换的时空演变与区域差异——基于长三角与大湾区城市群的比较研究

在长三角一体化和粤港澳大湾区建设上升为国家战略的背景下，对比分析两大城市群新旧动能转换水平、时空演变规律与区域差异，对两大城市群加快新旧动能转换步伐和推广先行示范效应具有重要现实意义。从需求侧、供给侧和结构转换侧三个动能维度构建评价指标体系，运用组合赋权法测算2012-2019年两大城市群36个城市新旧动能转换水平，并利用自然断点法、核密度法等探究两大城市群新旧动能转换时空演变规律与区域差异。研究得出：①长三角与大湾区城市群新旧动能转换分别呈现出“类N”型和“类U”型波动增长趋势，不充分性特征明显；②长三角城市群新旧动能转换表现出“西北低，东南高”的空间分布、“多极化”的空间格局以及“沙漏型”的空间层级特点，而大湾区城市群新旧动能转换表现出“由东向西”递减的空间分布、“单极化”的空间格局以及“倒金字塔型”的空间层级特点；③两大城市群核密度曲线延展性均由“右拖尾”转变为“收敛”趋势，表明两大城市群区域中心城市新旧动能转换中心极化现象得到逐年改善，中心城市对周边城市的虹吸效应减弱。     

基于三方演化博弈的在线健康社区用户隐私披露行为研究

[目的/意义]探究在线健康社区用户的隐私披露行为及其演化规律对促进用户隐私披露行为、提升社区隐私保护及完善互联网医疗体系均有重要意义。[方法/过程]文章构建了“用户—在线健康社区—政府”三方演化博弈模型,并求解了不同情境下的演化稳定策略,最后采用数值仿真验证了模型及演化结果的准确性。[结果/结论](1)用户披露个人隐私是形成最优演化路径的主要驱动力;(2)用户披露个人隐私后获得的医疗服务支持、情感支持等因素会影响用户的博弈策略;(3)隐私泄露造成的期望损失和实施“积极保护”付出的额外成本等因素会影响社区的博弈策略;(4)声誉收益和采取“高投入监管”付出的额外成本等因素会影响政府的博弈策略。对此,提出建议：多措并举,提升用户显性收益;健全机制,降低“积极保护”成本;强化监管,发挥奖惩双重效用。     

信息资源获取的成本和策略研究

用户有获取信息资源的自由，但这种自由是相对的。文章分析了用户获取信息过程中所付出的成本，并提出了设法降低用户信息获取成本的策略。     

浅谈英语学习中的“饭来张口”现象

在日常生活中,有一种现象叫“饭来张口”,而我们初中生的英语学习,也有一种“饭来张口”的现象,把英语学习成果完全依赖于老师的付出,把英语学习看作一种被动接受的过程。这种现象是一种依赖心理的反映。笔者从教学实践出发,探索改善此类现象的方法。     

那些年，我们一起经过的“艺考”

在过去的10年间,中国高校艺术类专业招生报考持续升温．2012年仍有近百万人参加“艺考”。催生“艺考热”的,是高考重压下的捷径心态,但对于很多艺考生而言,“艺考”已等同于高考。在不断增加的时间、经济成本以及身心付出的背后,曾经的“捷径”似乎已成“独木桥”。在这个由艺考生组成独特风景的季节,让人不由感叹：那些年,我们一起经过的“艺考”……     

东软NetEye电信级万兆DDoS防护方案

很久以来,电信级的DDoS防护一直是电信运营商面对的难题。由于电信的业务特点,电信网络遭受的DDoS攻击流量往往高达数10G。比如中国在2006年破获的最大僵尸网络规模为10万台,每台发出1Mbps流量的话,汇总后的流量高达100G,足以令任何一个运营商的网络服务瘫痪。另外，电信网络要求极高的可用性，绝大多数DDoS防护产品采用在线部署的方式，难以被运营商所接受。     

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