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41.
Critical information system in Interact is in face of increasingly security problems. More attention has been focused on the survivability of information system, which is the capability of system to continue its mission even in the presence of damage to the system. The authors first introduce the definition of survivability. According to four function properties of survivability, which are Resistance, Recognition, Recovery, and Adaption, the authors design a model of survivable system structure and then explain survivability requirement, survivability strategy in this model. Additionally, they provide possible technical solutions for the survivability of systems, categorized by different aspects of our survivability strategy. 相似文献
42.
Due to the sharp contradiction between rapidly developing housing construction in small-size town and quite low technological level, in this paper, the significance of setting up integrally technological system is emphasized and the suggestion that the technology should be integrated with the sustainable development, regional context and industrialization is put forward. 相似文献
43.
In this paper,notions on appropriate technology for the Steel Construction Congregated Apartments are proposed in order to deal with the technical impediment that arises from applying steel structural techniques to the congregated apartments.The appropriate technology for the steel construction congregated apartments is defined as systematic technologies that are in harmony with the status quo of Chinese productive force level,social culture and building technology,and as the strategies of choosing or balancing technology according to sustainable development principle.The principal design and constructing strategies of appropriate technology are as follows:(1) organization of residential space combined with steel construction techniques,(2) suitable structural system,(3) a new idea of fire resistance,and(4) kit building technique etc.A technological concept analysis about an ideal model of a steel construction system congregated apartment combined with the appropriate technology is also presented. 相似文献
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45.
This paper describes the development of a systems based model to characterise farmers’ decision-making process in information-intensive practices, and its evaluation in the context of Precision Agriculture (PA). A participative methodology was developed in which farm managers decomposed their process of decision-making into brief decision statements along with associated information requirements. The methodology was first developed on a university research farm in Denmark and further revised during testing on a number of research and commercial farms in Indiana, USA. Twenty-one decision-analysis factors were identified to characterise a farm manager’s decision-making process. Then, a general data flow diagram (DFD) was constructed that describes the information flows “from data to decision”. Illustrative examples of the model in the form of DFDs are presented for a strategic, a tactical and an operational decision. The model was validated for a range of decisions related to operations by three university farm managers and by five commercial farmers practicing PA for cereal, corn and soybean production in Denmark and in Indiana, USA. 相似文献
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山东省是农业大省,也是农机大省,无论是农业机械化水平,还是农机制造业水平都位具全国首位,在全省乃至全国制造业中扮演着重要角色。本文从企业集群化发展战略管理理论的分析入手,对山东省农机制造业企业的现状进行了研究,总结了国内外企业集群发展的成功经验,理论与实践相结合,提出了可供借鉴的集群发展模式和相应的对策建议。 相似文献
48.
波特竞争战略侧重从外部行业环境角度解释企业运营问题,但是实证分析结果证明资源对企业发展影响重大。针对目前尚无具体模式研究企业如何立足现有资源进行发展问题,本文基于资源基础论,将企业资源具体分为物质、信息、资金和知识资源(MICK),提出了MICK-4FI(四流集成)资源运营模式,借助投入产出模型构建MICK-4FI模式分析框架。文中利用聚焦和杠杆作用定性地解释了企业培育或者集成资源,即企业获取资源形成竞争优势的机理。本模式将资源基础论应用到企业实践层次,解决了企业通过集成运营内外部资源以求快速发展的路径依赖问题。资源运营理论从微观资源角度分析企业经营,与波特从宏观行业分析的理论共同构成一套系统的企业运营理论体系。 相似文献
49.
时序进气柴油机缸内分层与燃烧排放特征数值分析 总被引:1,自引:0,他引:1
缸内再循环废气(EGR)分布是发动机缸内EGR分层燃烧研究的重点与难点,由时序进气策略通过控制进气组分的充气时段来组织缸内EGR分层分布具有重要意义。以高压共轨重型柴油机为研究对象,采用CFD(Computation fluid dynamics)方法建立全参数数值仿真平台,研究不同时序进气组分经过进气及压缩过程后在缸内的分布特征及其对柴油机缸内燃烧及排放的影响。研究中以CO2代替EGR。研究结果表明,时序进气早期进气组分在气缸底部及燃烧室壁面附近分布较浓,后期进气则在气缸中心顶部分布较浓;时序进气能够获得显著的轴向分层分布;与均匀进气相比,缸内压力和温度偏低,燃烧滞后约0.7°CA,但放热率峰值偏高,NOx排放量降低51.2%,碳烟排放量降低13.4%。 相似文献
50.
我国西部地区水电开发问题探讨 总被引:1,自引:0,他引:1
水能资源是我国西部地区的优势资源,由于历史和政策的原因,开发利用程度相对较低,资源优势没有形成产业优势。在分析西部水能资源分布特点和开发现状的基础上,结合西部大开发和西电东送战略,提出目前水电产业存在的市场、政策和资金方面问题,探讨了加快西部水电开发的对策和建议。 相似文献