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41.
提高单片机系统可靠性的若干措施 总被引:1,自引:0,他引:1
由单片机构成的测控系统,大多应用于工业现场,存在着各种干扰。为保证微机系统可靠地工作,本文提出了若干提高单片机系统可靠性的措施,并进行了分析和介绍。 相似文献
42.
介绍了以MCS-51系列单片机为核心的定量检测系统的基本原理。并对其硬件结构和软件设计进行了详细地介绍。 相似文献
43.
用B3LYP/6 31 1 + +G 方法研究了H2 S与HO2 自由基之间的氢键。发现了三个能量极小点。同时做了H2 S·HO2 的振动频率分析。计算预测了能量整体最小点的构型为带有 2个扭曲的氢键的五元环结构 相似文献
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46.
近年来,分布式工作流系统已经成为计算机方面的研究热点。工作流管理系统能够在生产设计过程中提高效率、降低成本、提高竞争力。随着网络技术和软件技术的发展,工作流系统已经得到了广泛的应用。通过介绍工作流管理系统的基本概念和结构,提出了一种基于J2EE的工作流管理系统的设计方案,使用shark开源工作流引擎,采用分布式策略将工作流系统功能模块化。通过对总体过程进行描述,各个模块间的相互配合工作,实现了B/S结构的工作流管理系统并应用于飞行器设计系统中。 相似文献
47.
一、辽宁省农村水电发展现状
1.水能资源概况
辽宁省农村水电资源主要分布在东部的鸭绿江水系、辽河水系的浑河和太子河等,另有西部的大凌河和青龙河等。根据2003年全国水力资源普查结果表明,全省河流水能资源理论蕴藏量为202万千瓦(单站500千瓦装机以上)。 相似文献
48.
Jean-Baptiste Domergue Julie Lalande Daniel Beucher Pascale Satour Cyril Abadie Anis M. Limami Guillaume Tcherkez 《International journal of molecular sciences》2022,23(15)
Seed size is often considered to be an important trait for seed quality, i.e., vigour and germination performance. It is believed that seed size reflects the quantity of reserve material and thus the C and N sources available for post-germinative processes. However, mechanisms linking seed size and quality are poorly documented. In particular, specific metabolic changes when seed size varies are not well-known. To gain insight into this aspect, we examined seed size and composition across different accessions of barrel medic (Medicago truncatula Gaertn.) from the genetic core collection. We conducted multi-elemental analyses and isotope measurements, as well as exact mass GC–MS metabolomics. There was a systematic increase in N content (+0.17% N mg−1) and a decrease in H content (–0.14% H mg−1) with seed size, reflecting lower lipid and higher S-poor protein quantity. There was also a decrease in 2H natural abundance (δ2H), due to the lower prevalence of 2H-enriched lipid hydrogen atoms that underwent isotopic exchange with water during seed development. Metabolomics showed that seed size correlates with free amino acid and hexoses content, and anticorrelates with amino acid degradation products, disaccharides, malic acid and free fatty acids. All accessions followed the same trend, with insignificant differences in metabolic properties between them. Our results show that there is no general, proportional increase in metabolite pools with seed size. Seed size appears to be determined by metabolic balance (between sugar and amino acid degradation vs. utilisation for storage), which is in turn likely determined by phloem source metabolite delivery during seed development. 相似文献
49.
一种病毒进化型遗传算法 总被引:13,自引:0,他引:13
本文提出一种病毒进化型遗传算法VEGA。此算法在一般遗传算法的基础上,通过对病毒个体和宿主体行为及相互关系的模拟,使进化个体的多样性大大提高,算法更易趋于全局极化。模拟实验验证了VEGA的优良性能。 相似文献
50.
Within the field of Information Systems, a good proportion of research is concerned with the work organisation and this has,
to some extent, restricted the kind of application areas given consideration. Yet, it is clear that information and communication
technology deployments beyond the work organisation are acquiring increased importance in our lives. With this in mind, we
offer a field study of the appropriation of an online play space known as Habbo Hotel. Habbo Hotel, as a site of media convergence,
incorporates social networking and digital gaming functionality. Our research highlights the ethical problems such a dual
classification of technology may bring. We focus upon a particular set of activities undertaken within and facilitated by
the space—scamming. Scammers dupe members with respect to their ‘Furni’, virtual objects that have online and offline economic
value. Through our analysis we show that sometimes, online activities are bracketed off from those defined as offline and
that this can be related to how the technology is classified by members—as a social networking site and/or a digital game.
In turn, this may affect members’ beliefs about rights and wrongs. We conclude that given increasing media convergence, the
way forward is to continue the project of educating people regarding the difficulties of determining rights and wrongs, and
how rights and wrongs may be acted out with respect to new technologies of play online and offline.
Marie Griffiths moved from the IT industry into academia and is now based at the University of Salford as an EPSRC Academic Fellow. She has, and continues to research gender and ICTs. Recently she has embarked upon the study “Cybercitizens and their Virtual Pursuits” to understand the consequence of growing up and living in a technologically saturated environment. Her work has been published in journals such as Gender, Work and Organization, the European Journal of Information Systems and Information Communication and Society. Ben Light is Professor of Technology and Society at the University of Salford. His research concerns the appropriation of configurable technologies within work, organisations and society. This has led him to explore the use of large-scale enterprise resource planning packages, call centre technologies, social networking sites and digital games. He has published in journals such as Communications of the ACM, Information Systems Journal, New Technology, Work and Employment, the European Journal of Information Systems and the Journal of Information Technology. 相似文献
Ben LightEmail: |
Marie Griffiths moved from the IT industry into academia and is now based at the University of Salford as an EPSRC Academic Fellow. She has, and continues to research gender and ICTs. Recently she has embarked upon the study “Cybercitizens and their Virtual Pursuits” to understand the consequence of growing up and living in a technologically saturated environment. Her work has been published in journals such as Gender, Work and Organization, the European Journal of Information Systems and Information Communication and Society. Ben Light is Professor of Technology and Society at the University of Salford. His research concerns the appropriation of configurable technologies within work, organisations and society. This has led him to explore the use of large-scale enterprise resource planning packages, call centre technologies, social networking sites and digital games. He has published in journals such as Communications of the ACM, Information Systems Journal, New Technology, Work and Employment, the European Journal of Information Systems and the Journal of Information Technology. 相似文献