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1.
《普罗米修斯》2012,30(3):235-256
Abstract This paper seeks to understand how the possibility of a complementary relationship or its lack impacts dynamics of competition between two competing network technologies. It examines the cases of gas–electricity and telegraph–telephone competition. The two case studies suggest that the degree of complementarity greatly shapes the dynamics of competition between an entrenched network technology and a new competitor. When there is little scope for a complementary relationship, as in the case of the gas–electricity battle, the strategists for the new technology have to subvert the old system and build a new one on its ashes since there is little chance of coexistence. On the other hand, the possibility of a complementary relationship, as in the case of the telegraph–telephone battle, allows for the emergence of complex situations marked by coexistence interwoven with competition. These compromise positions, invariably involving re‐negotiation of boundaries, are tempting resting spots for battle weary contestants. As the relationship between the old and the new system evolves, the nature of the complementary relationship changes, especially in the relative power of the two systems, and even if eventually the old system fades away the process is a long and gradual one. 相似文献
2.
全国邮电高校大学生体质追踪调研 总被引：6，自引：0，他引：6
张丽 《西安体育学院学报》2002,19(1):68-71
全国邮电系统 6所高校共同对 1995年入校的 1863名本科生进行了连续四年的体质追踪测试 ,笔者按照《大学生体育合格标准》及“全国大学生体质研究会 ( 1982 )”中的特定指标对测试数据进行了比较研究。其结果表明 ,大学生在校四年期间体质变化呈屋脊型 ,一、二年级呈上升 ,二年级结束时为最佳 ,三、四年级呈下降 ,毕业前夕最差。邮电高校学生体质与 1979- 1995年全国大学生体质相比 ,身体形态处于同一水平 ,心脏功能、心血管机能、呼吸机能及耐力素质随着三、四年级体育必修课的停止而下降 ,各项指标在毕业前夕下降明显。笔者认为 ,这些现象与高校体育教学课程设置、课外活动管理方式有较大关系。 相似文献
3.
In the field of compatibility standards, an increasing number of companies claim to own so-called essential patents (i.e. those patents that are indispensable for designing and manufacturing products conforming to the standard). It is widely believed that the ownership of such patents is a very valuable bargaining tool in cross-license negotiations, while for non-producing firms such patents may result in a substantial stream of licensing revenues. In this paper we study the determinants of essential patent claims in compatibility standards. In particular, we assess the role of two main factors: the significance of the technological solution contained in the patent and the involvement of the applicant of the patent in the standardisation process. We examine the case of W-CDMA, one of the most successful standards in mobile telecommunications. We compare the patents claimed essential for this standard with a control group of randomly selected, unclaimed patents covering the same time period and technology classes. We find empirical evidence that both factors have significant impact on the probability that a patent is claimed as essential, but the involvement in the standardisation process is a stronger determinant than the technical value (‘merit’) of the patent. On the basis of our findings, we offer policy recommendations. 相似文献
4.
邢江 《中国教育技术装备》2010,(6):14-16
从分析通信英语教学现状和特点入手,运用建构主义学习理论积极开展教学改革,主要侧重于教材选择、立体化教学体系的构建、教学形式和考核方式等方面的教学改革。 相似文献
5.
Pernilla Gripenberg Ingjerd Skogseid Francesco Botto Andrea Silli Virpi Kristiina Tuunainen 《The Information Society》2004,20(1):3-14
This article compares four European information and communication technologies (ICT) development projects spawned by national and EU initiatives to create the “European information society.” These projects, which sought to support learning and better use of ICT, were all the result of opportunities opened up by political initiatives. The analysis indicates that the main problems that afflict these projects stem from varied expectations and interests of the major actors. These problems can be mitigated considerably if a feeling of ownership is generated among the participants. This sense of belonging, however, is difficult to foster in a “top-down” project. Hence there is a need for a better balance between the “top-down” and “bottom-up” influences in the development of such projects. 相似文献
6.
This article spotlights the need to develop capacity for ICT policy and regulation within developing countries. It argues that capacity should to be developed among all stakeholders, not solely within government agencies, because that would enable effective participation by many players in the regulatory process. The resulting participatory regulatory process will in turn increase accountability and procedural legitimacy. The article examines different approaches to developing in situ expertise, especially just-in-time learning and open-source research. 相似文献
7.
Fjodor Ruzic 《The Information Society》2013,29(3):109-116
Abstract All national information activities are increasingly interfaced through telecommunications. Today's users stand as witnesses to the formative stages of a totally networked society in the 21st century. Telecommunications technology lies at the root of formal concepts such as Inter‐Information Subjects Networks (IISNs) and National Information Systems (NISs), developed in the last few years. The term teleport refers to the new types of nodes that will form an overall integrated information traffic system. The challenge to all nations in the coming years is to provide or open these teleports to all types of national and social groups. Such teleports will give democracy a finished quality and otherwise bolster freedom by supporting the availability of all types of information. 相似文献
8.
何庆强 《涪陵师范学院学报》2004,20(5):93-95
作为第三代移动通信系统(3G)的关键技术，智能天线受到了国内外移动通信业的高度重视。文章阐述了智能天线的背景、结构原理、自适应算法以及研究现状和方向。 相似文献
9.
在假设投资项目的收益流服从几何布朗运动的条件下,讨论了项目投资最佳时点的选择问题,并基于最优停止理论,确定了投资时点的临界值以及贴现总收益的期望最大值。另外,给出了一些数值计算举例,并对结果进行了分析。 相似文献
10.
Brenton J. Malin 《Media History》2013,19(4):331-344
This paper explores a series of nineteenth century court cases involving the failed delivery of telegraphic ‘death messages.’ In these cases, friends or family members of a deceased or dying person failed to receive a telegram announcing the death or illness, and thus either missed their loved one's funeral or were unable to see them before they died. The intended recipient of the telegram then sued the telegraph company over the emotional suffering they experienced as a result. Those cases that were decided on behalf of the presumably emotionally wronged party offered a complex understanding of the public responsibilities of telecommunications companies. In the view of the courts that made these decisions, these companies were not simply responsible for transmitting messages. They also had an empathetic duty to the feelings of their customers. These court decisions have much to teach media historians about nineteenth century communications law and the emotional implications of new technologies. 相似文献