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1.
2.
基于灰色系统理论的资源型城市主导产业选择 总被引:1,自引:0,他引:1
以现有研究成果为基础,建立了资源型城市主导产业评价指标体系。基于灰色聚类的思想,采用主导产业优度的数学模型———定权聚类评估模型对辽宁省阜新市主导产业选择进行了实证分析。 相似文献
3.
阐述了SMC隔墙板组成材料及主要技术性能指标,介绍了SMC轻质内隔墙板在工程中的工艺流程及安装要点,提出具体的质量要求,指出SMC隔墙板质轻、隔音、性能稳定,有广泛的应用前景。 相似文献
4.
通过对花岗岩残积土的颗粒吸着含水率试验及测试数据的统计与分析,阐述花岗岩残积土的特性,并对土工试验中花岗岩残积土的颗粒吸着含水率的利用提出几点看法。 相似文献
5.
通过对西安与全国其他同等城市的横向对比,借以明确西安房地产市场的总体发展水平,了解制约西安市房地产发展的宏观约束条件,并找出西安房地产发展的潜力与不足,以便于为未来西安房地产业的健康有序发展,为政府有关部门制定政策提供决策依据。 相似文献
6.
The relationship between physical and chemical weathering indices of granites around Seoul,Korea 总被引:2,自引:0,他引:2
Sungsoo?Kim Hyeong-Dong?ParkEmail author 《Bulletin of Engineering Geology and the Environment》2003,62(3):207-212
In order to assess the relationship between chemical weathering indices and physical properties of granite, physical and chemical analyses were performed on both natural and artificially weathered granite samples from the Seoul area, where the pH of the rainfall occasionally drops to below 5. The results suggest that slake durability, uniaxial compressive strength, Ruxton ratio, Parker index, modified weathering potential index, chemical alteration index and loss on ignition effectively revealed changes of the degree of chemical weathering. However, the study showed no such good correlation between chemical and physical properties except dry density against loss on ignition and modified weathering potential index against uniaxial compressive strength. It is recommended that both physical and chemical indices should be used for the classification of weathering grade for the granites in the Seoul area.
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7.
This paper is partly tutorial by presenting well known classical decision theory in a slightly untraditional form, but it does also present thinking and results that have not been published in the engineering literature before. The paper introduces the mathematical modeling basis for rational formulation of decision criteria and public acceptance criteria connected to risk analysis of technical operations that may endanger human life and property. Public restrictions on the decisions concerning the design, construction and managing of the technical operation have in the past been imposed on the basis of the frequency and severity of experienced adverse events. No clear rationale to decide how restrictive the public should be in setting a boundary for allowable risk seems to have been applied. To clarify this problem, focus is on the difficulty of simultaneously having two decision makers, the owner that tries to optimize the net gain of the operation, and the public that has somewhat different preferences than the owner, but also strong interests in the success of the owner. The principles of rational decision are needed for appreciation of the problem. Recognizing that there is an insurance compensation value of a human life and a public money equivalent of a human life, where the last value usually is considerably larger than the first value, it is possible from the decision analysis to determine an upper limit that the public should impose on the ratio of the owner's expected loss rate to the expected gain rate. The public money equivalent of a human life is assessed by use of a recently in (Nathwani JS, Lind NC, Pandey MD. Affordable safety by choice: the life quality method. Waterloo, Ontario, Canada: Institute for risk Research, University of Waterloo, 1997) suggested Life Quality Index (LQI) that combines wealth in terms of Gross Domestic Product per person, life expectancy at birth, and yearly work time into a single number. The philosophy behind the published evaluations is that the prevention of a loss of a life is counteracted by a cost such that the LQI remains unchanged (Skjong R, Ronold K. Societal indicators and risk acceptance. In: 17th International Conference on Offshore Mechanics and Arctic Engineering, number OMAE98-1488. ASME; 1998; Rackwitz R. Optimization and risk acceptability based on the Life Quality Index. Structural Safety 2002;24:297–331.). 相似文献
8.
通过对新港工业区8个不同行业的给水用水量分析,获得了不同类型的行业单位用地用水量的实际数据。对实测数据的统计分析表明,随着科技的进步,很多产业的用水量都有较大程度的减少。阐述了给水量指标在开发区设计中的重要作用,指出规划应充分结合实际情况,有针对性地选择给水量指标,方能取得良好的经济效益和社会效益。 相似文献
9.
介绍了全国第二次公路普查中如何真实无误地完成路面现状数据的采集工作。首先对路面现状的各项技术指标作了充分、准确、明晰的定位认识,全面了解各项指标的准确意义,然后对路况普查表的路面现状采集数据作详细的阐述和说明,为公路数据库的建立提供依据。 相似文献
10.
D. B. Parkinson 《Civil Engineering and Environmental Systems》2013,30(6):304-310
The replacement of any limit state function by an equivalent linear function is discussed in detail and it is shown that there are several methods by which such an equivalence may be established. In the case of multiple failure mode problems the definition of fully equivalent linear functions requires the additional consideration of mode correlations. The manner in which this may be carried out is discussed and it is shown that, for most practical cases, a relatively simple analysis is likely to be sufficient to define the set of equivalent linear limit states, with the advantage that the established theory of such linear limit states may then be employed in the majority of reliability analyses. 相似文献