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11.
孔颖 《数字社区&智能家居》2007,(3):1429-1429,1438
针对C语言程序设计课程本身的特点,分析学习过程中存在的问题,强调实践的必要性。结合一些学校课程改革和实践的经验.提出面向应用的,科学的学习内容、方法和模式。同时提高学习者的专业动手能力。 相似文献
12.
The Modified Embedded Atom Method model for Pu metal is revised so that it more accurately captures the behavior of the Ziegler-Biersack-Littmark
model of ion-ion interactions. Two revision are tested with somewhat different stiffnesses in the 2-1000 eV range. The revised
models show higher damage levels at 20 KeV than an earlier model, suggesting that the behavior of the models above 100 eV
is dominating damage production, at least in the earlier stages of the cascade.
Work was performed at Los Alamos National Laboratory under the auspices of the US Department of Energy, under contract DE-AC52-06NA25396. 相似文献
13.
J. Dingel 《Formal Aspects of Computing》2002,14(2):123-197
Parallel computers have not yet had the expected impact on mainstream computing. Parallelism adds a level of complexity to
the programming task that makes it very error-prone. Moreover, a large variety of very different parallel architectures exists.
Porting an implementation from one machine to another may require substantial changes. This paper addresses some of these
problems by developing a formal basis for the design of parallel programs in the form of a refinement calculus. The calculus
allows the stepwise formal derivation of an abstract, low-level implementation from a trusted, high-level specification. The
calculus thus helps structuring and documenting the development process. Portability is increased, because the introduction
of a machine-dependent feature can be located in the refinement tree. Development efforts above this point in the tree are
independent of that feature and are thus reusable. Moreover, the discovery of new, possibly more efficient solutions is facilitated.
Last but not least, programs are correct by construction, which obviates the need for difficult debugging. Our programming/specification
notation supports fair parallelism, shared-variable and message-passing concurrency, local variables and channels. The calculus
rests on a compositional trace semantics that treats shared-variable and message-passing concurrency uniformly. The refinement
relation combines a context-sensitive notion of trace inclusion and assumption-commitment reasoning to achieve compositionality.
The calculus straddles both concurrency paradigms, that is, a shared-variable program can be refined into a distributed, message-passing
program and vice versa.
Received July 2001 / Accepted in revised form May 2002 相似文献
14.
15.
牛哲成.一种自制硬件诊断磁带的方法.测并技术,1994,18(2):149~154硬件诊断磁带是由用于对计算机硬件系统各组成部分进行功能检查、状态测试和故障检测的诊断测试程序集构成的一种专用工具磁带。本文提出了一种用户在PE3200系列计算机裸机环境下自己制作硬件诊断磁带的方法,井涉及到具体的程序实现。用该方法制作的硬件诊断磁带操作简单。对进一步搞好PE3200系列计算机的维护,开发完善PE3200系列计算机硬件诊断系统具有实际意义。 相似文献
16.
陈金强 《数字社区&智能家居》2007,(9):1460-1461
中等职业学校一般开设VB、VC及数据库等涉及程序设计的计算机课程。本文拟就程序设计中一题多解的教学方法进行探讨。 相似文献
17.
就工程项目管理企业知识管理建设框架进行了理论的阐述,从建立支持企业知识共享、创新的平台和促进该平台运作的机制提出了知识管理中最重要的两点,指出进行企业知识管理建设对企业未来发展具有重要的影响。 相似文献
18.
水利电力自动化设备TCP/IP通信协议栈的选择 总被引:2,自引:1,他引:1
鲍兴川 《水电自动化与大坝监测》2007,31(6):1-4,27
TCP/IP通信协议栈产品层出不穷,文中列举了几种适合水利电力行业使用的TCP/IP通信协议栈产品,进行了分析和测试比较,评价了各协议栈产品的优缺点,评估了其性价比和实用性,为水利电力行业设备的TCP/IP通信协议栈选择提供了参考依据. 相似文献
19.
Aseel Berglund Erik Berglund Anders Larsson Magnus Bang 《Universal Access in the Information Society》2006,4(4):300-327
The television (TV) is one of the most common entertainment devices in homes. Searching and finding TV programs is a common task and using TV guides is one way of performing this. This paper presents three studies that are focused on examining audiences’ TV habits and TV guide usage, evaluating a new concept based on linking paper and pen with TV technology, and studying the audiences’ attitudes toward and anticipated interest in the future guide. The results of our first study emphasize the value of using paper based TV guides and also identify the deficiencies. We also found indications that the advantages and disadvantages of paper-based TV guides are related to the physical properties of paper. Thus, we suggest a solution that uses digital pen and paper technology to offer a new interaction method for TV. A research system “Paper Remote”, is developed and used in the two subsequent studies. Viewers tick designated areas on the paper-based guide to perform actions such as channel switching. However, this solution is not a substitute for the remote control device. We argue that these user studies on linking digital paper to the TV for everyday information navigation illuminate the possibilities of providing innovative solutions also for home information systems also. 相似文献
20.
Alcohol expectancy-challenge programs are effective in changing expectancies and reducing drinking in college men (J. Darker & M. S. Goldman. 1993. 1998); however, recent evidence suggests this protocol might not be effective for women (M. E. Dunn, C. Lau, & I. Y. Cruz, 2000). This study was designed to reevaluate the effectiveness of a social/sexual expectancy-challenge intervention in college women reporting moderate to heavy alcohol use. Forty-six undergraduate women were randomly assigned to the prevention or control condition. Participants reported alcohol expectancies at pre- and posttest and monitored their drinking patterns daily for 6 weeks. The program was effective in changing some expectancies but did not reduce drinking. This further confirms differences in the mechanisms by which expectancy-challenge programs function for men and women. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献