美国教育技术的应用现状和发展趋势研究

本文分析了教育技术在美国高等教育和企业培训等领域的应用和发展。并指出,教育技术渗透到教学过程是现代和未来教育的发展方向。这种新型教育形式将对现行教育产生积极的影响。     

入世后我国照明产业的机遇和对策的探讨

2001年12月11日中国结束了历时15年之久的“入世谈”，正式加入了世界贸易组织－WTO，从此，中国将真正融入到世界经济的过程中，并在经济全球化的时代大背景下以崭新的姿态参与国际竞争，中国入世必将对国内各行业带来不同程度的冲击，下文就我国照产业的发展状况及入后的就对策略，未来趋势作粗略的剖析和探讨。     

浅析服务式老年公寓与老年社区的设计要点和趋势

随着"银发时代"的到来,我国社会的老龄化进程正在加速发展.本文重点研究为日益增长的老年人口提供的服务式老年公寓与老年社区的设计方法,通过分类阐述和举例论证,总结设计要点和未来发展趋势,供设计和研究工作者参考使用.     

近代辐射防护之趋向

本文试图根据辐射防护的着眼点转向随机效应的观点,来阐明体现在 ICRP 26号出版物中的近代辐射防护的剂量限制体系,并介绍与讨论了正当化、最优化与限量化原则。强调指出这个体系与传统的阈值观点的差别。由于随机效应的随机性,小的概率与长的潜伏期,使我们难以获得充分的有关人的剂量效应的直接资料,指出现有的部分有用资料实系来自正当性可疑的实践,而有效的辐射防护反而使我们得不到更多的资料。阐述了小剂量下随机效应的线性无阈假定发生率的可叠加原理及由此发展起来的躯体有效剂量当量与 ICRP 有效剂量当量。文中强调指出,ICRP的防护标准是把所有职业受照者看作是相同的,在这个意义上由线性假定论证了按器官平均剂量(或积分剂量)估计效应的合理性。解释了最优化的差分分析原理及其在实际运用中所存在的困难。     

Water quality trends in the Tarkwa gold-mining district,Ghana

A detailed hydrochemical investigation has been undertaken to establish whether mining has adversely affected streams in the Tarkwa gold-mining district and, if so, to what extent. The results show that streams that pass through mining areas and receive mine water exhibit significant spatial and temporal variations in their major ion hydrochemistry. Water analyses of perceived pristine areas reveal that the study area has undergone silicate weathering, but in mining areas, carbonate weathering was inferred. The inconsistency is attributed to the chemistry of mine waters discharging into receiving streams. This is supported by the average pH values of 6.48 for pristine streams and 7.74 for those affected by mine water. Trace element analysis did not show significant changes from the norm except for discharges from a spoil heap, which exhibited hydrochemical characteristics consistent with acid mine drainage. Saturation indices determined for the water samples reflect the sandstone–quartzite–phyllite lithology and intense weathering regime of the area as a result of the humid tropical climate.     

美国信息安全发展对中国发展战略的启示

近两年,美国总统奥巴马执政以来出台了一系列网络安全战略,使之成为美国国家安全战略的一部分。国家层面的战略计划、法律法规也相继出炉,体现了美国将迎来信息安全政策的重大调整。本文主要介绍了近两年以来美国的信息安全战略部署和信息安全立法动向,为我国的信息安全战略调整提出了几点借鉴的启示。     

Chinese Garden Research in the 21st Century International Academia —A Diachronic Analysis of Journal Studies in the History of Gardens & Designed Landscapes and Dumbarton Oaks Library and Collection

In response to increasing attention from international academia on Chinese gardens, this article advances China’s landscape studies by exploring international research trends on Chinese gardens during the 21st century. It mainly adopts a diachronic perspective to examine the journal Studies in the History of Gardens & Designed Landscapes—a leading journal, and Dumbarton Oaks Research Library and Collection (Trustees for Harvard University)—international academia’s leading institution on landscape studies. Using a bibliometric approach, it first carries out a statistical analysis of the rules and trends of development to explore the distribution patterns of Chinese gardens. Based on this analysis, it uses time series analysis to study the relationships of related academic discourses and contexts. The study reveals that Chinese garden studies led by Chinese scholars has attracted increasing attention from international academia and has involved growing numbers of scholars from various disciplines. Consequently, it has not only shaped much of the output from China and Britain, but is also driving a paradigm shift away from studying Chinese classical gardens to modern designed landscapes, drawing upon a monolithic approach to investigate the pluralistic, and from focusing on Chinese national interaction to transnational interaction.     

天然气替代丙烷切割在液压支架中的推广使用

通过对天然气和丙烷在金属切割应用中的特点及成本进行分析、试验、比较,总结出增效天然气比丙烷混合气体更适用于板料切割,采用天然气代替丙烷切割是一种必然趋势。     

Effect of Task Complexity and Stimulus Duration on Perceptual-Motor Performance of Two Disparate Age Groups

Abstract

This study was concerned with two task dimensions, complexity and stimulus duration, which previous research had shown to accentuate or reduce performance. differences between age groups. Young and old groups made an unguided movement at the onset of one stimulus light in a four-light display. Task complexity was varied by altering the number of response alternatives (1 or 2) while holding the display constant. Two stimulus durations were used: 0110 sec and 2.0 sec. Old subjects reacted 30 per cent slower and moved 7G percent slower than young. Both reaction time and movement time were slower for the complex task than for the simple. The difference between simple and complex movement time was significantly greater for old subjects than for young./ Young subjects moved faster with the 0.110 sec stimulus while old subjects moved faster with the 2.0 sec stimulus.     

Representation model and learning algorithm for uncertain and imprecise multivariate behaviors,based on correlated trends

The computational representation and classification of behaviors is a task of growing interest in the field of Behavior Informatics, being series of data a common way of describing those behaviors. However, as these data are often imperfect, new representation models are required in order to effectively handle imperfection in this context. This work presents a new approach, Frequent Correlated Trends, for representing uncertain and imprecise multivariate data series. Such a model can be applied to any domain where behaviors recur in similar—but not identical—shape. In particular, we have already used them to the task of identifying the performers of violin recordings with good results. The present paper describes the abstract model representation and a general learning algorithm, and discusses several potential applications.