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1.
本文以ZH公司为例分析了环境影响评价中经济分析的发展现状,并由此外延深入辨析了建设项目环境影响经济损益分析、建设项目环保措施费用效益分析、建设项目费用效益分析三者的内涵与外延、区别与联系;在分析了环境影响评价中经济分析内容的基础上针对性的提出了可行性方法和针对性对策。  相似文献   

2.
本文以ZH公司为例分析了环境影响评价中经济分析的发展现状,并由此外延深入辨析了建设项目环境影响经济损益分析、建设项目环保措施费用效益分析、建设项目费用效益分析三者的内涵与外延、区别与联系;在分析了环境影响评价中经济分析内容的基础上针对性的提出了可行性方法和针对性对策。  相似文献   

3.
本文阐述了企业产品质量分析的重要性,分析了企业产品质量分析工作中存在的主要问题,研究提出了企业提升产品质量分析工作有效性的措施。  相似文献   

4.
运用ANSYS软件对气液两相流海洋立管进行了流固耦合特性分析,包括模态分析和动力学分析。模态分析研究了有无流固耦合存在时立管振动模态的变化以及流体边界条件对立管固有频率和阵型的影响;同时,将仿真分析同DNV公式求解的固有频率进行了对比验证。动力学分析研究了单、双向流固耦合振动分析,并将单、双向流固耦合进行了对比分析,同时考虑了立管支承方式、流体边界条件对立管振动的影响,提出了立管减振措施。分析结果对海洋立管的优化设计和运行的可靠性提供了重要的理论意义。  相似文献   

5.
建筑工程经济分析,是建筑工程必不可少的部分。经济分析不仅存在于施工的阶段,而且在决策和设计阶段,蕴济分析也非常重要。本文研究了提高混凝土强度、建筑工程项目费用的经济分析以及钢筋混凝土基础设施腐蚀的全寿命经济分析,论述了建筑工程项目经济分析的应用过程。重点分析了对建筑工程项目进行经济分析的方法。  相似文献   

6.
概述了腐蚀失效分析的意义,根据实际腐蚀失效分析工作,从现场调查、实验室分析两个方面阐述了腐蚀失效分析的思路,并综合一些典型的腐蚀失效案例对常用的腐蚀失效分析方法进行了简单的归纳。对腐蚀失效分析工作进行了展望。  相似文献   

7.
本文提出了用信号流程图进行行星齿轮变速箱运动分析及载荷分析的方法,并以单行星排为例,介绍了用信号流程图法进行运动分析及载荷分析的步骤,获得了分析的结果.  相似文献   

8.
失效分析的任务、方法及其展望   总被引:12,自引:4,他引:8  
概述了失效与失效分析的概念,以及失效分析的意义、作用和任务;以防止失效为出发点,论述了失效分析的工作思路、程序和辩证方法;展望了失效分析的未来。  相似文献   

9.
在简要分析了确定空气弹簧刚度传统方法的基础上,从有限元的角度,提出了分析空气弹簧刚度的新思路,并初步解决了用有限元分析空气弹簧刚度需要解决的几何非线性,气压载荷变化等问题,而后,以回转型空气弹簧为例,分析了其垂向刚度特性,分析结果表明,用有限元分析空气弹簧刚度是可行的,最后,根据空气弹簧的实际情况,提出改进分析的措施。  相似文献   

10.
通过宏观分析、红外光谱分析、热分析和高压毛细管流变分析对ASA树脂制件分层原因进行了分析。结果表明:发生分层的ASA树脂制件混入了PP树脂,两者流动性和结晶性的差异导致了制件的分层。  相似文献   

11.
In 1985, the CODATA Bulletin published a Report of its Task Group on Thermophysical Properties of Solids which analyzed available data on, and gave recommended values for, the heat capacity of Cu, Fe, W, and Al2O3, the thermal expansion of Cu, Si, W, and Al2O3, the electrical resistivity of Cu, Fe, Pt, and W, the thermal conductivity of Al, Cu, Fe, and W, and the absolute thermopower of Pb, Cu, Pt, and W. The analysts for the different properties were R. B. Castanet, S. J. Collocott, P. D. Desai, C. Y. Ho, J. G. Hust, R. B. Roberts, C. A. Swenson, and G. K. White. The present paper is an updated version of the earlier report and includes more recent data which change some of the recommended values. notably the heat capacity of Cu and W and the thermal expansion of Si and W.  相似文献   

12.
以质量控制观念及大数据管理为视角,阐述了计量性的概念、意义和价值,指出了计量性实质上就是产品状态参量的可激励性、可控制性和可观测性。按照技术目标与能力要求,将计量性划分为5个不同的技术等级,以贯穿从产品的设计制造到使用维护的全寿命过程。讨论了计量性对提升产品成熟度的作用。  相似文献   

13.
梁志国  孟晓风 《计量学报》2011,32(4):361-367
提出了使用正弦波激励评价波形记录仪触发延迟的新方法,通过一个波形在有触发延迟和无触发延迟时,采集序列间的相位差对应的时间差来最终判定触发延迟结果。讨论了影响评价结果不确定度的几个主要误差来源,包括信号源误差、采集序列的谐波失真、噪声与非谐波失真、抖动、软件拟合运算误差等,同时给出了不确定度评定结果。以一组实验结果验证了所述方法的有效性和切实可行性。  相似文献   

14.
Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.  相似文献   

15.
Vendor-managed inventory (VMI) represents the methodology through which the upstream stage of a supply chain (vendor) takes responsibility for managing the inventories at the downstream stage (customer) based on previously agreed limits. VMI is another method by which supply chains can be managed, and, owing to centralised decision-making and constant information sharing, the benefits are much higher than in traditional supply chain case. However, there exists a lack of research that identifies the dimensions of VMI, benefits of VMI, methods, and levels used in the VMI environment. The focus of this paper is to explore the existing literature on VMI, to categorise it according to the criteria evaluated, and to present a systematic review. In this study, we have classified the review into three categories such as dimension-based, methodology-based, and level-based. From the thorough literature review, we have identified six dimensions of VMI: namely, inventory, transportation, manufacturing, general benefits, coordination/collaboration, and information sharing. In addition, there are, three methodological classifications: modelling, simulation, and case studies. Finally, we will consider the level-based classification. Based on the review, several recommendations that improve the performance of VMI are presented.  相似文献   

16.
In this paper, using furfural residue as a template, porous calcium titanate (FPCT) was prepared by a sol-gel method and characterized by XRD, SEM, and nitrogen adsorption method. The conditions of preparation were investigated. The adsorption capabilities of FPCT for heavy metal ions were studied, and the adsorption mechanism was investigated. The results show that the calcium titanate was porous, and material is composed of crystals in nanoparticle size with a small amount of calcium sulfate impurities, while the sulfuric acid in furfural residue is fixed as the calcium sulfate in the material. The adsorbed quantity is affected by the pH value of medium and time. When the pH value of medium is 5, and oscillating adsorption lasts for 30?min, the adsorbed quantities of Cd, Pb, Zn, Cu, and Ni are 118.04, 197.96, 64.98, 56.85, and 47.91?mg/g, respectively. The adsorption conforms to the Langmuir adsorption isothermal model and pseudo-second-order kinetic equation, and is a spontaneous endothermic process driven by entropy. After adsorption, adsorbents can be regenerated with 1?mol/L nitrate solution. It is used for eliminating Cd, Pb, Zn, Cu, and Ni in wastewater and the results are satisfactory.  相似文献   

17.
The compliance with increasingly stricter emission standards is a challenge for the automotive industry, which requires the utilization of lightweight materials e. g. aluminium and high‐strength steels. Hereby, the load‐optimized design of body parts and the reduction of wall thicknesses are enabled. But, due to the use of dissimilar materials, common joining technologies are reaching their limits. On the one hand, joining by welding is often not possible because of different melting temperatures. On the other hand, joining by forming with additional fasteners increases the cycle time and the costs. However, joining by forming without fasteners is often limited by the mechanical properties of the joining partners. The innovative shear‐clinching technology combines shear‐cutting and clinching in a single stage process and thereby enables joining by forming of materials with high differences regarding their mechanical properties. However, by the combination of the sub‐processes cutting and joining, the complexity of the technology is increased. Thus, within the scope of this work, the fundamental mechanisms in shear‐clinching and their interactions as well as the robustness of the process are analysed, in order to promote the applicability of the technology.  相似文献   

18.
Defense and attack of complex and dependent systems   总被引:1,自引:0,他引:1  
A framework is constructed for how to analyze the strategic defense of an infrastructure subject to attack by a strategic attacker. Merging operations research, reliability theory, and game theory for optimal analytical impact, the optimization program for the defender and attacker is specified. Targets can be in parallel, series, combined series-parallel, complex, k-out-of-n redundancy, independent, interdependent, and dependent. The defender and attacker determine how much to invest in defending versus attacking each of multiple targets. A target can have economic, human, and symbolic values, subjectively assessed by the defender and attacker. A contest success function determines the probability of a successful attack on each target, dependent on the investments by the defender and attacker into each target, and on characteristics of the contest. The defender minimizes the expected damage plus the defense costs. The attacker maximizes the expected damage minus the attack costs. Each agent is concerned about how his investments vary across the targets, and the impact on his utilities. Interdependent systems are analyzed where the defense and attack on one target impacts all targets. Dependent systems are analyzed applying Markov analysis and repeated games where a successful attack on one target in the first period impacts the unit costs of defense and attack, and the contest intensity, for the other target in the second period.  相似文献   

19.
The data produced by high-throughput genomic techniques are often high dimensional and undersampled. In these settings, statistical analyses that require the inversion of covariance matrices, such as those pursuing supervised dimension reduction or the assessment of interdependence structures, are problematic. In this article we show how the idea of adding noise to the bootstrap, pioneered by Efron, and Silverman and Young, in the late seventies and eighties, can be used to overcome undersampling and effectively estimate the inverse covariance matrix for data sets in which the number of observations is small relative to the number of variables. We demonstrate the performance of this approach, which we call augmented bootstrap, on simulated data and on data derived from genomic DNA sequences and microarray experiments. This invited paper is discussed in the comments available at: , , , , , , , . This work was partially supported by NIH grant HG02238 to W. Miller, NIH grant R01-GM072264 to K. Makova, and NSF grant DMS-0704621 to R.D. Cook, B. Li and F. Chiaromonte.  相似文献   

20.
The primary raw materials used in the imperial smelting process (ISP) are Zn and Pb concentrates. Dust generated in the course of ISP is recycled. The identified sphalerite grains indicate the presence of Pb, Fe, Cd sulfides, Fe and Zn oxides, as well as accompanying elements (Ca, Mn, Cu, As, Se, Ag, Sn, and Sb). The tests performed have demonstrated the differentiation in the content of the accompanying elements in sphalerite present in both charge mixture as well as in dusts. This differentiation may be an indication of the migration of these element from sphalerite to the products or to waste during the process.  相似文献   

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