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991.
硅-玻璃静电键合中的电流-时间特性分析   总被引:2,自引:0,他引:2  
在微传感器和微机械结构的静电键合实验中 ,当加电压到键合片对上时 ,外电路的电流迅速上升到一定值后 ,不是逐渐减小 ,而是较缓慢的继续上升 ,或在某一值停留一段时间再逐渐减小到最小值。通过对实验现象的分析 ,认为键合的电流 -时间特性主要是下述两个过程的综合反映 ,键合过程中接触电阻的减小引起的电流增大和空间电荷区形成引起的电流减小 ,正是由于这两个主要因素导致了上述现象的存在  相似文献   
992.
We propose a new conceptual model for understanding technology evolution that highlights dynamic and highly interdependent relationships among multiple technologies. We argue that, instead of considering technologies in isolation, technology evolution is best viewed as a dynamic system or ecosystem that includes a variety of interrelated technologies. By considering the interdependent nature of technology evolution, we identify three roles that technologies play within a technology ecosystem. These roles are components, products and applications, and support and infrastructure. Technologies within an ecosystem interact through these roles and impact each others’ evolution. We also classify types of interactions between technology roles, which we term paths of influence. We demonstrate the use of our proposed model through examples of wireless networking (Wi-Fi) technologies and a business mini-case on the digital music industry.
Robert J. KauffmanEmail:
  相似文献   
993.
Design-code traceability recovery: selecting the basic linkage properties   总被引:1,自引:0,他引:1  
Traceability ensures that software artifacts of subsequent phases of the development cycle are consistent. Few works have so far addressed the problem of automatically recovering traceability links between object-oriented (OO) design and code entities. Such a recovery process is required whenever there is no explicit support of traceability from the development process. The recovered information can drive the evolution of the available design so that it corresponds to the code, thus providing a still useful and updated high-level view of the system.

Automatic recovery of traceability links can be achieved by determining the similarity of paired elements from design and code. The choice of the properties involved in the similarity computation is crucial for the success of the recovery process. In fact, design and code objects are complex artifacts with several properties attached. The basic anchors of the recovered traceability links should be chosen as those properties (or property combinations) which are expected to be maintained during the transformation of design into code. This may depend on specific practices and/or the development environment, which should therefore be properly accounted for.

In this paper different categories of basic properties of design and code entities will be analyzed with respect to the contribution they give to traceability recovery. Several industrial software components will be employed as a benchmark on which the performances of the alternatives are measured.  相似文献   

994.
遗传程序设计方法综述   总被引:33,自引:2,他引:31  
近年来,遗传程序设计(genetic programming,GP)的研究引起了人们很大的关注,它运用遗传算法(genetic algorithm,GA)的思想,通过生成计算机程序来解决问题,介绍了遗传程序设计的研究状况以及目前的研究进展,概述了它的基本算法、主要特点、理论与技术,同时介绍了一些GP实现系统以及主要的应用领域,最后探讨了遗传程序设计的研究方向。  相似文献   
995.
本研究建立了常系数线性齐次递归关系的数学模型及求解理论。  相似文献   
996.
The Future of Enterprise System-Enabled Organizations   总被引:3,自引:0,他引:3  
Companies are beginning to expect to gain strategic value from the implementation and operation of enterprise systems (ES). Currently dominating trends in business are sense-and-respond business models, globalization, corporate realignment, virtual organizations and accelerated product life-cycles. Available and evolving features of enterprise systems are summarized in a framework, concluding that present capabilities of enterprise systems correspond only to some extend to the new practices required to respond to these corporate challenges, and that ERP vendors strive to fill the gap. By integrating higher management functions enterprise systems will also impact on the practice of executives. The future work of an executive is illustrated by a fictitious example.  相似文献   
997.
城市河、湖水系连通工程设置过船建筑物,大多是为增加城市旅游亮点、开发旅游资源而设置的通航设施,除有其功能性要求外,尚包括水资源调配、水生态保护、景观视觉效果等特殊性要求。文中以桂林市"两江四湖"环城水系工程为例,论述了过船建筑物的布点原则,分析了不同类型过船建筑物的应用特点,提出了在不同环境条件及景观要求下过船建筑物的选型思路和理念,对创造人水和谐城市、开发旅游资源具有借鉴意义。  相似文献   
998.
董家根  栾承梅  徐明 《江苏水利》2013,(10):41-42,45
从矛盾观、自然观、系统观等唯物辩证法的方法论入手,对河流生态保护进行了哲学反恩。必须运用系统的观点来看待河流系统,保护河流系统的完整性和连续性;必须减轻人类活动对河流自然形态的限制,恢复河流的千姿百态;必须深刻认识河流的演化规律,正确处理好人类和河流之间的关系,不断实现人水和谐;必须尊重河流生命,从辩证的角度在河流开发利用与河流保护之间不断寻求折中点,通过最大努力保护和修复河流生态。  相似文献   
999.
Reproductive success of stream‐spawning Oncorhynchus fishes (Pacific salmon, rainbow trout, cutthroat trout and their allies) may be greatly affected by stream discharge or its covariate, stream temperature, during the spawning season. Because such data for the physical environment may not have been routinely collected as part of previous investigations of these fishes, identification of simple but robust indices of historic, seasonal stream discharge and temperature, using long‐term climate data sets, would be important, especially to investigations of historic population dynamics. This study examined statistical associations among several climate variables and the spawning‐season (approximately June) discharges and temperatures of Clear Creek, a Yellowstone Lake tributary used by spawning Yellowstone cutthroat trout, Oncorhynchus clarkii bouvieri (YCT), from the lake. Correlation analysis showed that total water‐year degree‐days (calculated on the basis of mean daily air temperature > 0°C) at Lake Village, on the lake's north shore, was a robust index (both negative and positive, respectively) of consecutive, total semi‐month metrics of creek discharge and temperature during the YCT spawning season. This study (and subsequent use of the Lake Village degree days metric as an environmental variable in a dynamic, age‐structured model of the lacustrine–adfluvial YCT population of Clear Creek) showed how exploratory analyses of the fragmentary but long‐term and regionally unique data sets for Clear Creek discharge and temperature revealed a simple but robust index of climate variation important to understanding the historic dynamics of Clear Creek's YCT population, which is a key spawning stock of Yellowstone Lake. In addition, the extensive statistical associations among the climate variables, along with the temporal trends in two key variables, broadly showed how climate varied across the Yellowstone Lake region during the past several decades. Those observations have implications for the historic, seasonal hydrology of all Yellowstone Lake tributaries used by spawning YCT. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
1000.
柘林大坝第二溢洪道泄洪闸结构稳定,位移和渗流运行性态正常,泄流能力满足原设计要求。但尾渠内人口稠密、房屋林立,一旦泄洪,如何保障尾渠内的人民生命财产安全是本工程泄洪运行需要重点关注的问题。因此,电厂必须与地方政府联动,制定出切实可行的防洪抢险应急预案,警钟长鸣、定期演练,以能在泄洪非常时期把损失降到最低。  相似文献   
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