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61.
基于层次分析法建立客户综合价值分析体系 总被引:2,自引:1,他引:2
随着上海市电力公司用电客户数量的不断增加,要求全面了解客户,为大客户提供个性化服务,这就需要建立客户综合价值分析体系,用以挖掘客户为企业创造的巨大价值.通过调研给出了客户综合价值评价指标体系,同时阐述了运用层次分析法为客户综合价值指标进行赋权的方法,并进行了实例分析.实践表明,所建立的指标体系及指标赋权方法,能为供电企业进行客户价值分析提供理论和实践上的借鉴. 相似文献
62.
基于数据挖掘技术的教学质量分析评价系统的实现 总被引:2,自引:0,他引:2
提出基于多维立方体的数据挖掘思想和方法以及一种定量分析和定性评价相结合的教学质量综合测评方法,并运用数据仓库和联机分析处理技术构建一种“平面”和“立体”相结合的教学质量综合测评体系,建立多维综合测评联机分析挖掘模型,实现在高校教学质量分析评价中的应用。 相似文献
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The paper presents a simulation system (SCP) that determines the cutting forces in the ball-end milling process. The system is based on numerical methods, computer programme, theoretical knowledge of technological processes, machining and tests performed. The system for simulation of the cutting process combines the technological data base, the analytical and experimental model and the data base SCP. The experimental model contains a collection of variables of the cutting process by means of sensors and transformation of those data into numerical values, which are a starting point for data calculation of characteristic coefficients of materials. The analytical model is used to estimate the tangential, radial and axial cutting forces, along with a material data base obtained from cutting experiments. Ball-end milling test has been conducted to verify simulation results. The simulation results, are the basis for the development of the tool-designing model and for the model of optimization of the machining process cutting parameters. 相似文献
65.
用层次分析法安排电力系统事故后火电机组恢复的次序 总被引:11,自引:1,他引:11
在电力系统事故恢复过程中,火电机组的恢复复次序对电力系统的恢复有重大影响本文在分析了影响火电机组恢复及出力的各种因素后,将定性与定量分析方法组合,建立了火电机组恢复的层次模型,最后给出了算例。 相似文献
66.
具有井筒相分离和层间窜流的层状油藏渗流井底压力精确解 总被引:6,自引:3,他引:6
关于具有窜流的多层油藏井底压力解,国内外有不少学者进行了研究,D.Bourdet提出的双渗模型最具实用性,但该模型在表皮系数为负时,数值计算极不稳定,应用受到限制,本文首次用有效井径概念,导出了一个数值计算相当稳定的双渗模型,另外还考虑了井筒相分离影响,本模型解大大扩大了Bourdet模型的应用范围。 相似文献
67.
Elena Bozhevolnaya Anders Lyckegaard Ole. T. Thomsen Vitaly Skvortsov 《Composites Part B》2004,35(6-8):619-627
The paper considers local bending effects induced in the vicinity of inserts in sandwich panels. Such local bending effects are associated with an increase of bending stresses in the sandwich faces and normal and shear stresses in the sandwich core. An earlier developed analytic model [Proceedings of the Sixth International Conference on Sandwich Structures (ICSS-6) (2002) 551] is adapted for the case of a sandwich panel with circular insert, with elastic properties differing from those of the core. The locally induced stresses in the faces and core due to presence of the insert are expressed via simple analytic relations (and charts) enabling an estimation of these local stresses. Finite element analysis is employed to demonstrate the applicability of the analytic model, and a good correspondence between the numerical and the analytical data is found. A study case related to marine applications, namely a circular insert in a sandwich deck panel used for mounting of a rigging fixture, is considered, and optimization of an existing design is carried out. 相似文献
68.
Static indentation and unloading response of sandwich beams 总被引:1,自引:0,他引:1
This paper deals with analysis of foam core sandwich beams subject to static indentation and subsequent unloading (removal of load). Sandwich beams are assumed continuously supported by a rigid platen to eliminate global bending. An analytical model is presented assuming an elastic-perfectly plastic compressive behaviour of the foam core. An elastic part of indentation response is described using the Winkler foundation model. Upon removal of the load, an elastic unloading response of the foam core is assumed. Also, finite element (FE) analysis of static indentation and unloading of sandwich beams is performed using the FE code ABAQUS. The foam core is modelled using the crushable foam material model. To obtain input data for the analytical model and to calibrate the crushable foam model in FE analysis, the response of the foam core is experimentally characterized in uniaxial compression, up to densification, with subsequent unloading and tension until tensile fracture. Both models can predict load–displacement response of sandwich beams under static indentation and a residual dent magnitude in the face sheet after unloading along with residual strain levels in the foam core at the unloaded equilibrium state. The analytical and FE analyses are experimentally verified through static indentation tests of composite sandwich beams with two different foam cores. The load–displacement response, size of a crushed core zone and the depth of a residual dent are measured in the testing. A digital speckle photography technique is also used in the indentation tests in order to measure the strain levels in the crushed core zone. The experimental results are in good agreement with the analytical and FE analyses. 相似文献
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分析仪器和其他传统工业一样,正在信息技术的改造下,向微型化、智能化、自动化和网络化方向发展。分析仪器作为数据获得的源头技术,必将在信息技术发展中起到重要作用,将从被动转向主动,并促进信息技术的发展。分析工作者也将是未来物联网不可或缺的生力军。 相似文献