25 resultados para Process capability analysis

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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个体软件过程(PSP)是由卡内基×梅隆大学软件工程研究所的Humphrey领导开发的.它是一种可用于控制、管理和改进个人工作方式的自我持续改进过程.随着工业界对软件过程改进需求的日益增长,PSP成为了软件组织为达成完全(从宏观到微观)量化过程管理研究中的一个热点课题.软件过程研究表明,高水平的个体软件过程能力是软件项目成功的关键,如何进行有效的个体软件过程能力度量是PSP中的一个核心问题.现有方法不能同时有效处理个体软件过程能力度量中的可变规模收益、多变量输入/输出以及决策者偏好问题.提出了一种综合了数据包络分析(DEA)和层次分析法(AHP)的个体软件过程能力评价方法--PSPADA,介绍了PSPADA的个体软件过程能力评价模型和核心算法(集成决策者偏好和估计规模收益).实验结果显示,PSPADA能够在考虑决策者偏好的同时,有效地进行多指标、规模收益可变的量化评估.

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Immersion lithography has been considered as the mainstream technology to extend the feasibility of optical lithography to further technology nodes. Using proper polarized illumination in an immersion lithographic tool is a powerful means to enhance the image quality and process capability for high numerical aperture (NA) imaging. In this paper, the impact of polarized illumination on high NA imaging in ArF immersion lithography for 45 nm dense lines and semi-dense lines is studied by PROLITH simulation. The normalized image log slope (NILS) and exposure defocus (ED) window are simulated under various polarized illumination modes, and the impact of polarized illumination on image quality and process latitude is analyzed. (C) 2007 Elsevier GmbH. All rights reserved.

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现代流程工业产生了大量与生产状态相关的过程数据,其庞大的规模凸显了传统数据分析方法运算复杂度过高、分析规模受限的不足。同时,流程工业生产过程中所包含的一些复杂性,如传感器数据中的高噪音以及异步采样所导致的数据时标不统一等,都增加了过程数据分析的难度。 为了应对上述挑战,本文将粒度计算的思想引入流程工业中的过程数据分析领域。粒度计算是信息处理领域中一种新兴的概念和计算范式,其核心思想是通过适度放松精度要求,在较大粒度上进行分析以提高方法整体的效率和鲁棒性。 本文重点研究了面向过程数据的粒度化分析方法,并围绕该方法的关键性质展开了深入细致的论证,在此基础上给出了选择粒度的方法和准则,最后我们还通过具体实例对上述方法的有效性进行了应用验证。 论文的主要贡献体现在: (1)将粒度计算的思想和过程数据分析方法相结合,提出了一种粒度化的过程数据分析方法,并证明了在特定条件下粒度化的数据分析能够得到原问题解的下界或下确界,为粒度化过程数据分析方法奠定了坚实的理论基础。 (2)深入探讨了不同粒度下过程数据分析的计算复杂性变化情况,提出了一种利用多粒度分析挑选最佳分析粒度的方法。该方法针对现有数据分析方法难于应对海量数据的缺点,可以根据具体应用的精度需求灵活地调整分析粒度,从而降低数据分析的总体计算复杂性。 (3)针对过程数据分析中面临的稳态周期评估问题,提出了一种基于多粒度分析的过程数据稳态周期检测算法。该算法基于我们提出的过程数据质量评估指标,能够灵活地调整查询周期,提供符合应用系统质量需求的数据,同时尽量减少运行开销。 (4)针对大规模软测量面临的计算效率问题,提出了一种基于多粒度分析的软测量方法。该方法通过构建一组粒度化的软测量模型,并依次在多个粒度中求解,最终确定一个既能满足特定精度需求又能确保运算效率最高的粒度。该方法已经得到实践检验并取得良好的效果。

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现代流程工业产生了大量与生产状态相关的过程数据,其庞大的规模凸显了传统数据分析方法运算复杂度过高、分析规模受限的不足。同时,流程工业生产过程中所包含的一些复杂性,如传感器数据中的高噪音以及异步采样所导致的数据时标不统一等,都增加了过程数据分析的难度。 为了应对上述挑战,本文将粒度计算的思想引入流程工业中的过程数据分析领域。粒度计算是信息处理领域中一种新兴的概念和计算范式,其核心思想是通过适度放松精度要求,在较大粒度上进行分析以提高方法整体的效率和鲁棒性。 本文重点研究了面向过程数据的粒度化分析方法,并围绕该方法的关键性质展开了深入细致的论证,在此基础上给出了选择粒度的方法和准则,最后我们还通过具体实例对上述方法的有效性进行了应用验证。 论文的主要贡献体现在: (1)将粒度计算的思想和过程数据分析方法相结合,提出了一种粒度化的过程数据分析方法,并证明了在特定条件下粒度化的数据分析能够得到原问题解的下界或下确界,为粒度化过程数据分析方法奠定了坚实的理论基础。 (2)深入探讨了不同粒度下过程数据分析的计算复杂性变化情况,提出了一种利用多粒度分析挑选最佳分析粒度的方法。该方法针对现有数据分析方法难于应对海量数据的缺点,可以根据具体应用的精度需求灵活地调整分析粒度,从而降低数据分析的总体计算复杂性。 (3)针对过程数据分析中面临的稳态周期评估问题,提出了一种基于多粒度分析的过程数据稳态周期检测算法。该算法基于我们提出的过程数据质量评估指标,能够灵活地调整查询周期,提供符合应用系统质量需求的数据,同时尽量减少运行开销。 (4)针对大规模软测量面临的计算效率问题,提出了一种基于多粒度分析的软测量方法。该方法通过构建一组粒度化的软测量模型,并依次在多个粒度中求解,最终确定一个既能满足特定精度需求又能确保运算效率最高的粒度。该方法已经得到实践检验并取得良好的效果。

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Analysis of the isothermal, and nonisothermal crystallization kinetics of Nylon-11 is carried out using differential scanning calorimetry. The Avrami equation and that modified by Jeziorny can describe the primary stage of isothermal and nonisothermal crystallization of Nylon-11. In the isothermal crystallization process, the mechanism of spherulitic nucleation and growth are discussed; the lateral and folding surface free energies determined from the Lauritzen-Hoffman equation are sigma = 10.68 erg/cm(2) and sigma(e) = 110.62 erg/cm(2); and the work of chain folding q = 7.61 Kcal/mol. In the nonisothermal crystallization process, Ozawa analysis failed to describe the crystallization behavior of Nylon-ii. Combining the Avrami and Ozawa equations, we obtain a new and convenient method to analyze the nonisothermal crystallization kinetics of Nylon-11; in the meantime, the activation energies are determined to be -394.56 and 328.37 KJ/mol in isothermal and nonisothermal crystallization process from the Arrhonius form and the Kissinger method. (C) 1998 John Wiley & Sons, Inc.

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This thesis bases on horizontal research project “The research about the fine structure and mechanical parameters of abutment jointed rock mass of high arch dam on Jinping Ⅰ Hydropower Station, Yalong River” and “The research about the fine structure and mechanical parameters of the columnar basalt rock mass on Baihetan Hydropower Station, Jinsha River”. A rounded system about the fine structure description and rock mass classification is established. This research mainly contains six aspects as follow: (1) Methods about fine structure description of the window rock mass; (2) The window rock mass classification about the fine structure; (3) Model test study of intermittent joints; (4) Window rock mass strength theory; (5) Numerical experimentations about window rock mass; (6) The multi-source fusion of mechanical parameters based on Bayes principle. Variation of intact rock strength and joint conditions with the weathering and relaxation degree is studied through the description of window rock mass. And four principal parameters: intact rock point load strength, integration degree of window rock mass, joint conditions, and groundwater condition is selected to assess the window rock mass. Window rock mass is classified into three types using the results of window rock mass fine structure description combined with joints develop model. Scores about intact rock strength, integrality condition, divisional plane condition and groundwater conditions are given based on window rock mass fine structure description. Then quality evaluation about two different types of rock mass: general joint structure and columnar jointing structure are carried out to use this window rock mass classification system. Application results show that the window rock mass classification system is effective and applicable. Aimed at structural features of window structure of “the rock mass damaged by recessive fracture”, model tests and numerical models are designed about intermittent joints. By conducting model tests we get shear strength under different normal stress in integrated samples, through samples and intermittent joints samples. Also, the changing trends of shear strength in various connectivity rates are analyzed. We numerically simulate the entire process of direct shear tests by using PFC2D. In order to tally the stress-strain curve of numerical simulation with experimental tests about both integrated samples and through samples, we adjust mechanical factors between particles. Through adopting the same particle geometric parameter, the numerical sample of intermittent joints in different connective condition is re-built. At the same time, we endow the rock bridges and joints in testing samples with the fixed particle contacting parameters, and conduct a series of direct shear tests. Then the destructive process and mechanical parameters in both micro-prospective and macro-prospective are obtained. By synthesizing the results of numerical and sample tests and analyzing the evolutionary changes of stress and strain on intermittent joints plane, we conclude that the centralization of compressive stress on rock bridges increase the shear strength of it. We discuss the destructive mechanics of intermittent joints rock under direct shear condition, meanwhile, divide the whole shear process into five phases, which are elasticity phase, fracture initiation phase, peak value phase, after-peak phase and residual phase. In development of strength theory, the shear strength mechanisms of joint and rock bridge are analyzed respectively. In order to apply the deducted formulation conveniently in the real projects, a relationship between these formulations and Mohr-Coulomb hypothesis is built up. Some sets of numerical simulation methods, i.e. the distinct element method (UDEC) based on in-situ geology mapping are developed and introduced. The working methods about determining mechanical parameters of intact rock and joints in numerical model are studied. The operation process and analysis results are demonstrated detailed from the research on parameters of rock mass based on numerical test in the Jinping Ⅰ Hydropower Station and Baihetan Hydropower Station. By comparison,the advantages and disadvantages are discussed. Results about numerical simulation study show that we can get the shear strength mechanical parameters by changing the load conditions. The multi-source rock mass mechanical parameters can be fused by the Bayes theory, which are test value, empirical value and theoretical value. Then the value range and its confidence probability of different rock mass grade are induced and these data supports the reliability design.

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Evaluating the mechanical properties of rock masses is the base of rock engineering design and construction. It has great influence on the safety and cost of rock project. The recognition is inevitable consequence of new engineering activities in rock, including high-rise building, super bridge, complex underground installations, hydraulic project and etc. During the constructions, lots of engineering accidents happened, which bring great damage to people. According to the investigation, many failures are due to choosing improper mechanical properties. ‘Can’t give the proper properties’ becomes one of big problems for theoretic analysis and numerical simulation. Selecting the properties reasonably and effectively is very significant for the planning, design and construction of rock engineering works. A multiple method based on site investigation, theoretic analysis, model test, numerical test and back analysis by artificial neural network is conducted to determine and optimize the mechanical properties for engineering design. The following outcomes are obtained: (1) Mapping of the rock mass structure Detailed geological investigation is the soul of the fine structure description. Based on statistical window,geological sketch and digital photography,a new method for rock mass fine structure in-situ mapping is developed. It has already been taken into practice and received good comments in Baihetan Hydropower Station. (2) Theoretic analysis of rock mass containing intermittent joints The shear strength mechanisms of joint and rock bridge are analyzed respectively. And the multiple modes of failure on different stress condition are summarized and supplied. Then, through introducing deformation compatibility equation in normal direction, the direct shear strength formulation and compression shear strength formulation for coplanar intermittent joints, as well as compression shear strength formulation for ladderlike intermittent joints are deducted respectively. In order to apply the deducted formulation conveniently in the real projects, a relationship between these formulations and Mohr-Coulomb hypothesis is built up. (3) Model test of rock mass containing intermittent joints Model tests are adopted to study the mechanical mechanism of joints to rock masses. The failure modes of rock mass containing intermittent joints are summarized from the model test. Six typical failure modes are found in the test, and brittle failures are the main failure mode. The evolvement processes of shear stress, shear displacement, normal stress and normal displacement are monitored by using rigid servo test machine. And the deformation and failure character during the loading process is analyzed. According to the model test, the failure modes quite depend on the joint distribution, connectivity and stress states. According to the contrastive analysis of complete stress strain curve, different failure developing stages are found in the intact rock, across jointed rock mass and intermittent jointed rock mass. There are four typical stages in the stress strain curve of intact rock, namely shear contraction stage, linear elastic stage, failure stage and residual strength stage. There are three typical stages in the across jointed rock mass, namely linear elastic stage, transition zone and sliding failure stage. Correspondingly, five typical stages are found in the intermittent jointed rock mass, namely linear elastic stage, sliding of joint, steady growth of post-crack, joint coalescence failure, and residual strength. According to strength analysis, the failure envelopes of intact rock and across jointed rock mass are the upper bound and lower bound separately. The strength of intermittent jointed rock mass can be evaluated by reducing the bandwidth of the failure envelope with geo-mechanics analysis. (4) Numerical test of rock mass Two sets of methods, i.e. the distinct element method (DEC) based on in-situ geology mapping and the realistic failure process analysis (RFPA) based on high-definition digital imaging, are developed and introduced. The operation process and analysis results are demonstrated detailedly from the research on parameters of rock mass based on numerical test in the Jinping First Stage Hydropower Station and Baihetan Hydropower Station. By comparison,the advantages and disadvantages are discussed. Then the applicable fields are figured out respectively. (5) Intelligent evaluation based on artificial neural network (ANN) The characters of both ANN and parameter evaluation of rock mass are discussed and summarized. According to the investigations, ANN has a bright application future in the field of parameter evaluation of rock mass. Intelligent evaluation of mechanical parameters in the Jinping First Stage Hydropower Station is taken as an example to demonstrate the analysis process. The problems in five aspects, i. e. sample selection, network design, initial value selection, learning rate and expected error, are discussed detailedly.

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Synthetic Geology Information System(SGIS) is a part of the theory of Engineering Geomechanics-mate-Synthetics(EGMS), is also a development of its technical methodology. SGIS includes ways of geology engineering investigation, design, and construction. Although SGIS has an integrate theory frame, and some parts of it have gained great progress, the completion of SGIS is a continuous and accumulative process. This paper analyses the ways and principle of building knowledge database and model database, summarizes the experts' experience on exploration methods selection and the characters of exploration models, combining with the application of Decision Support System(DSS) in Decision support of Synthetic Exploration Methods for Railway engineering Geology. By the analysis of hierarchy structure of the model database, the effects of geology engineering factors on the selection of exploration methods are expressed. By the usage of fuzzy patterns recognize, hierarchy structure analysis, fuzzy collection closement analysis etc, the software of DSS for engineering design and construction are developed. At same time, by the development of Monitoring Data Analysis System and experiment data management system of Hydro-power project, this paper discussed the data management of science experiment of Hydro-power project by the usage of synthetic database and the usage of Geography Information System(GIS) and DSS technics. The technic of visual operation of data process and project monitoring system are presented. The intelligence algorithm of self-adoption is carried out to improve the data process and analysis of monitoring. Items of the project theoretical analysis and data process are designed in detail. All the theory and technical methods presented in this paper are one part of SGIS, in which the application of DSS and GIS, is an important step of the progress and completion of SGIS.

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The foundation of reservoir model and residual oil prediction have been the core of reservoir detailed description for improved oil production and enhanced oil recovery. The traditional way of sandstone correlation based on the geometrical similarity of well-logs which emphasizes "based on the cycle and correlating from larger to smaller" has shown its theoretical limits when explaining the correlating and the scale, geometry, continuity, connectivity of sandstones and the law of the reservoir property. It has been an urgent and difficult subject to find new theory and methods to solve the reservoir correlation and property prediction. It's a new way to correlate strata and found framework of reservoir through the process-response analysis in the base-level cycles. And it is also possible to analyze the reservoir property in reservoir framework. Taking the reservoir of zonation 6-10 in S3~2 of Pucheng Oil Field in Henan Province as an example, we founded the detailed reservoir stratigraphic framework through base-level correlation. In the strata frame, sediment distribution and its development are discussed based on sediment volume partitioning and facies differentiation analysis. Reservoir heterogeneities and its relation to base-level are also discussed. The analysis of primary oil distribution shows the base-level controlled oil distribution in reservoir. In this paper, subjects as following are discussed in detail. Based on the analysis of sedimentary structure and sedimentary energy, the facies model was founded. Founding stratigraphy framework through base level analysis In the studying zone, one long term cycle, 6 middle term cycles and 27 short term cycles was identified and correlated. 3 Predicting the property of reservoir for improving oil development The base level controlled the property of sandbody. The short and very short term cycle controlled the pattern of heterogeneities in sandbody, and the middle and long term cycle controlled the area and inter-layer heterogeneities. On the lower location of the middle and long term base level, the sandbody is well developed, with a wide area and large thickness, while on the high location of base level, there is an opposite reservoir character. 4 The studying of reservoir development response and oil distribution making a solid base for development adjustment Primary oil distribution is controlled by base level location. It tells that the sandbody on the high base level location was poor developed for its difficulty to develop. While on the low location of the base level, the sandbody is well developed for its relative easy to develop and dominant role in the development, but high residual oil for its high original oil content.

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To further investigate the mechanism of acoustic emission (AE) in the rock fracture experiment, moment tensor analysis was carried out. The AE sources characterized by crack sizes, orientations and fracture modes, are represented by a time-dependent momen

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The microstructural heterogeneity and stress fluctuation play important roles in the failure process of brittle materials. In this paper, a generalized driven nonlinear threshold model with stress fluctuation is presented to study the effects of microstructural heterogeneity on continuum damage evolution. As an illustration, the failure process of cement material under explosive loading is analyzed using the model. The result agrees well with the experimental one, which proves the efficiency of the model.