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941.
食品废物含有大量的油脂,本研究对食品废物的油脂含量进行了连续监测,以其为原料开展生物柴油的制备研究,并对其组成进行测试分析,同其他原料所得生物柴油作对比,结果表明:食品废物的平均含油率均超过了10%(干基)。利用食品废物中提取的废弃油脂制取的生物柴油以棕榈酸甲酯、油酸甲酯和亚油酸甲酯含量最高,分别为38.70%、亚油酸甲酯18.32%和棕榈酸甲酯31.72%,其组成与以植物油为原料合成生物柴油组成基本相似,符合作为柴油替代品的要求。 相似文献
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944.
A.A. SiddiquiS.M.V. Gwynne 《Safety Science》2012,50(3):478-493
Simulation tools are often used to establish pedestrian and evacuee performance. The accuracy and reliability of such tools are dependent upon their ability to qualitatively and quantitatively capture the outcome of this performance; i.e. whether the simulated agents perform the expected acts and take the expected amount of time to complete them. This article investigates the relationship between simulating individual agent actions and generating reliable emergent conditions (e.g. congestion). Once this relationship is established for a particular tool, it can then be used to investigate the conditions that may emerge in certain scenarios and mitigate against them. This article presents a simple framework for categorising real-world observations and then translating these observations into the simulated environment - extracting key information from the data collected to configure the simulation tool as required. The article addresses the qualitative benefits of representing individual-level actions, and, to a lesser degree, the quantitative benefits, although this effort is limited given the nature of the data. It tests this relationship using observations made at the Hajj, specifically the Sa’ee where large numbers of pilgrims perform religious rites in concert. Several scenarios are simulated using the buildingEXODUS model, enabling the importance of individual-level behaviours upon emergent conditions to be investigated, even when simulating relatively large crowds of up to 15,000 people. 相似文献
945.
中国区域创新效率及其影响因素 总被引:3,自引:0,他引:3
效率问题是中国科技创新过程中需重点关注的一个问题.本文以1998-2005年中国30个省份的研发面板数据为基础,以专利为创新的产出指标,R&D经费支出和R&D人员投入为创新的投入指标,应用随机前沿模型对各地区创新过程中的效率情况进行了实证测评,并就影响创新效率的环境因素进行了进一步探讨.主要的研究发现有:R&D经费支出和R&D人员投入对创新产出均有显著的正向影响,且R&D人员投入比R&D经费支出具有更高的产出弹性;劳动者素质对区域创新效率的提高有显著的正影响,而产业结构有显著的负影响,这可能与专利并不能全面反映高技术产业创新绩效有关;各地区的创新效率呈明显上升的趋势,且与地方经济发展结合越来越紧密;区域创新效率有收敛的趋势,后进地区的追赶效应明显.本文结论为国家及地方创新工程建设提供政策参考. 相似文献
946.
The US is entering into a new era in space. The Vision for Space Exploration (VSE) (Bush, 2004) announced by the US President has been fleshed out during the Exploration Systems Architecture Study (ESAS) (ESAS Team Final Report, 2005) and work has been underway since then to develop a generation of launch vehicles to implement the preferred 1.5 launch architecture identified in the study. The 0.5 part of the launch set indicates the smaller Crew Launch Vehicle in the new set designated Ares I by NASA. The Ares I was selected by the team because analysis had shown that its complement of a solid first stage, with a liquid H2/O2 cryogenic second stage offered the best potential balance among cost, risk and performance. In particular the risk that this conceptual design would impose on the crew once matured was forecasted to be an order of magnitude better than the current matured crewed launcher set, the Soyuz and the Space Shuttle (Isakowitz, 2004). This forecast relied heavily on the experience of the heritage systems upon which the concept was based, specifically the heritage of the Shuttle solid rocket boosters and the experience with cryogenic upper stage engines from the Apollo and Shuttle era. Even with this strong heritage in play, it was recognized by the ESAS Risk Analysts that it would be necessary to mature the design with a set of test flights prior to placing the crew at risk. However the question was and is: “How many test flights are necessary before a crewed flight should be attempted?”This is the question that this paper addresses. That is, it is clear that the number of test flights is related to the desired safety level and that this, in turn, is related to what safety goal should be assigned to enable the crewed flight. Further, demonstration of goal achievement is again in turn related to how much of the heritage base can be captured in the new design. In the extreme, for a completely “new” design, the demonstration would be bounded by the requirements of the identical, repeatable experiments of classical probability theory (Mises, 1957). Even if the tens, or even hundreds of launches that this would require would be financially possible, tests of developmental systems are seldom, if ever, identical and repeatable because the design is modified to address the failure events observed. On the other hand, if the design was completely identical to the heritage then the heritage demonstrated reliability could be subsumed compared to the goal without further testing. This paper addresses the role of heritage in a developmental environment in the establishment of a minimum goal for the initiation of crewed missions and the testing required for its demonstration. 相似文献
947.
程俊梅 《石油化工环境保护》2000,(2)
洛阳石化总厂通过建立与实施国际标准化环境管理体系 ,特别是通过体系中 5个要素的运行与控制 ,使企业的环境管理更加规范、有效。同时通过不断追求新的环境目标、指标的实现 ,使企业的环境行为得到了改进 ,不仅取得了环境效益 ,而且取得了经济效益。 相似文献
948.
人为失误原因分析与控制对策研究 总被引:11,自引:1,他引:11
杨大明 《中国安全科学学报》1997,7(1):14-17
研究了人为失误对系统安全的影响,分析了人为失误产生的原因及其影响因素,并就煤矿安全管理中人为失误的控制提出了针对性措施 相似文献
949.
灾害史研究中的年代换算及其软件 总被引:1,自引:0,他引:1
“灾害史中的年代换算(TCHD)”软件是进行年代换算的专用软件。本文研究了几种主要历法的年代换算的具体算法.介绍了该软件的结构,流程和功能.TCHD软件使灾害学和历史学等领域的研究人员摆脱了传统的朔闰表式的历法对照和检索方式,并成为灾害史工作计算机化的一部分。 相似文献
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