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会计电算化是管理现代化的重要组成部分 ,会计电算化系统的安全性一直是管理信息系统的难点之一。根据多年实践的经验 ,提出采用系统生成技术改进提高会计电算系统的安全性 ,有助于广大中小企业会计电算化的推广应用。 相似文献
314.
介绍了建筑防火设计的现状及发展趋势,特别提到计算机模拟技术在建筑工程防火性能化设计中的重要性,并且应用CFD系列防火软件中的FDS软件对室内火灾的特征进行了模拟与描述,体现了计算机模拟技术在建筑防火设计中应用的优越性与实效性。 相似文献
315.
玻璃幕墙是城市建筑中常见的装饰和围护结构,但在阳光照射下,会产生不舒适眩光甚至是强烈的失能眩光,因此,眩光污染是对城市道路交通安全的重要威胁之一。对眩光的监测主要是针对眩光亮度、方位和环境光亮度分布的监测。采用彩色CCD相机测量光环境亮度的分布,并结合计算机图像处理技术,对采集的图片进行亮度提取、处理计算,最后得出眩光评价值。通过实验室模拟玻璃幕墙眩光实验,对不同中性密度滤光片下的测量结果进行对比,从而选择恰当中性密度滤光片对实际建筑眩光测量,得出不同时间的眩光测量值。通过一系列的实验结论,将有助于眩光的污染防治和城市交通的安全防护。 相似文献
316.
The concept of sustainable development (SD) has highly been debated since it was presented 25 years ago, with ‘hard science’ approaches on one side and more process-oriented approaches on the other side. Academic teaching in SD has emerged in response to this in very different contexts, partly mirroring this academic debate. Some master’s programmes in SD take a strong science approach, while other programmes focus on the process of implementing sustainability projects, sometimes connected with forms of action research and teaching. In this article, we identify diverse views on the concept of SD as well as views on most relevant modes of teaching. We discuss core competencies required for sustainability professionals in their working practices and we organise them in three main clusters: Know, Interact and Be (KIB). The article presents the results of a worldwide survey, which addresses these visions on the concept of SD, the capabilities needed for ‘sustainable development professionals’ and the teaching approach needed. The analysis is based on the responses of 54 lecturers and 287 students active in 34 SD master’s programmes on all continents. The results of this worldwide survey are discussed. We observe in practice some gaps between preferences and practice. Looking at what both lecturers and students see as essential topics to address, some topics get relatively less attention (like the population issue). The identified core competencies (KIB) are supported and all addressed in practice, while the ‘Be’ competencies receive relatively less attention. Suggested consequences for academic teaching include a further matching of programmes with perceived needs and bridging the gap between the experienced teaching approaches in practice with such identified needs. 相似文献
317.
The ever-increasing amount of electronic scrap and the steadily-decreasing contents of the precious metals used in electronics, as well as the ever-growing environmental awareness, challenges such conventional precious-metal-oriented recycling techniques as pyrometallurgy. Separation and beneficiation of various materials encountered in electronic scrap might provide a correct solution ahead. In this context, mechanical separation-oriented characterization of electronic scrap was conducted in an attempt to evaluate the amenability of mechanical separation processes. Liberation degrees of various metals from the non-metals, which are crucial for mechanical separation, were analyzed by means of a grain counting approach. It is found that the metallic particles below 2 mm achieve almost complete liberation. Particle shapes were also quantified through an image processing system. The results obtained show that the shapes of the particles, as a result of shredding, turn out to be heterogeneous, thereby complicating mechanical separation processes. In addition, separability of various materials was ascertained by a sink–float analysis. It has been shown that density-based separation techniques shall be viable in separating metals from plastics, light plastics (ABS, PS and PVC, etc.) from glass fiber reinforced resins and aluminum from heavy metals. Specifically, a high quality copper concentrate can be expected by density-based separation techniques. Moreover, FT-IR spectra of plastics pieces from the light fractions after the sink–float testing show that PC scrap primarily contains ABS, PS and PVC plastics with the density range of +1.0–1.5 g/cm3, whereas PCB scrap mainly contains glass fiber reinforced epoxy resins plastics with the density range of +1.5–2.0 g/cm3. 相似文献
318.
David T. Ford Darryl W. Davis 《Journal of the American Water Resources Association》1985,21(1):135-144
ABSTRACT: The U.S. Army Corps of Engineers has broad, nationwide water resources planning and management responsibilities. In response to the needs of Corps professionals, the Hydrologic Engineering Center (HEC) has developed and supports a family of computer programs designed to aid them in their work. These programs include catchment, channel, alluvial, and statistical process models, system operation models, plan evaluation models, and data management programs. These models individually and collectively have been used throughout the Corps in a wide range of water resources planning studies. 相似文献
319.
Terry W. Rothermel Milton S. Sachs Frank O'Shaughnessy 《Journal of the American Water Resources Association》1971,7(4):867-877
ABSTRACT The Office of Saline Water, which has federal responsibility for developing low-cost, saline sources of fresh water, has recognized the need for an improved method of forecasting the future potential of desalting in this country. The magnitude of the role of desalting will influence the plans of federal, state, and local water resource agencies and the research and development programs of manufacturers. A dynamic simulation model has been developed by Arthur D. Little, Inc. under contract by OSW to translate relevant factors of water supply and demand into a forecast of desalting potential. The model projects the needs for desalting in 20 hydrologic regions of the U.S. Model performance has thus far been demonstrated by the development of a forecast and a battery of related sensitivity tests. Current results indicate the following potential desalting capacities: 225 MGD in 1980; 2,250 MGD in 2000; and 7,000 MGD in 2020. Significant improvements in desalting economics promise to increase these potentials by a factor of four or five by 2000-2020. Model inputs and results are continuing to be refined. When completed, OSW will have a dynamic tool with which to guide its R&D program. 相似文献
320.
计算机和信息技术(IT)在一些大型石油公司的HSE管理中得到了广泛的应用,这些应用主要包括建立电子文件的HSE管理体系,健康、安全和环境数据的档案库,进行风险的危害预测和分析,通过企业网实现子公司间的HSE管理文件共享或通过E-mail进行信息交流等。 相似文献