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A review of robust design methods for multiple responses   总被引:1,自引:0,他引:1  
Problems in engineering design often involve determining design variable settings to optimize individual product performance for multiple criteria, which are often in conflict. We review mathematically rigorous techniques from the statistical literature for finding a vector x of design variable settings, which produces an optimal compromise solution among a group of prioritized response variables. The best compromise solution is typically gained by optimizing an objective function, which incorporates the prioritized demands of multiple responses. Since most multi-response objective functions are constructed by combining the functions used to optimize univariate responses, a review of the prominent univariate approaches is presented first. A multivariate approach from the engineering literature called the compromise Decision Support Problem is also reviewed. Finally a table comparing the relative merits of the different multivariate approaches summarizes the article in a concise and user-friendly fashion.  相似文献   
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Lists of core competencies or critical capabilities are popular and plentiful. This article makes the case that a single core competency or critical capability accounts for professional success: the exercise of judgment. Judgment is the critical determinant of the quality of professional decisions, actions, and evaluations. Practical models of judgment are presented. The elements and dynamics of judgment are detailed. Individual, group, and organization implications are explored. Coaching and consulting interventions are explained. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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When liquid water contacts a zirconium-barium-lanthanum fluoride glass, at least three different processes occur. Barium and zirconium fluoride dissolve into the water, water penetrates into the glass, and zirconium fluoride crystals grow on the glass surface, in static solution. The rate of dissolution, as measured by solution analysis, is possibly controlled by diffusion in the solid surface; surface blockage and surface reactions are other possible kinetic steps involved. Diffusion in solution is not the controlling mechanism. Hydrogen profiles in the glass surface suggest that the penetration rate of water into the glass is controlled by diffusion and a surface reaction.  相似文献   
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This study examined partner violence in the year before and the year after individually based, outpatient alcoholism treatment for 301 married or cohabiting male alcoholic patients and used a demographically matched nonalcoholic comparison sample. In the year before treatment, 56% of the alcoholic patients had been violent toward their female partner, 4 times the rate of 14% in the comparison sample. In the year after treatment, violence decreased significantly to 25% of the alcoholic sample but remained higher than in the comparison group. Among remitted alcoholics after treatment, violence prevalence of 15% was nearly identical to the comparison sample and half the rate among relapsed patients (32%). Thus, partner violence decreased after alcoholism treatment, and clinically significant violence reductions occurred for patients whose alcoholism was remitted after treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The effect of fibre orientation on the dry sliding wear of continuous B(SiC) fibre reinforced aluminium alloy composites was investigated using a pin-on-disc wear testing machine. The metal-matrix composites (MMC) samples were tested in the normal (N), parallel (P) and antiparallel (AP) orientations sliding against a steel counter disc at a fixed speed of 1 m s–1 under loads of from 12 to 60 N.The results showed that for the matrix alloy and MMCs, the average wear increased linearly with load. Wear of the MMCs was insensitive to fibre content but for composites with fibre contents at or above the minimum of 16 vol% used for this work, the wear rate was about 18% of that of the unreinforced matrix. Fibre orientation had a minor effect on wear rate; the N orientation gave the lowest wear rate with the AP orientation slightly higher and the P orientation significantly higher.The average coefficients of friction of the MMCs in N and AP orientations decreased linearly with increased wear rate and non-linearly with increased load, but the P orientation was insensitive to either variable.It was concluded from these results and a metallographic examination that the mechanism of wear of MMCs was essentially oxidative wear of the matrix. The hard fibres modified this to slightly different degrees depending on their orientation relative to the wear surface and sliding direction.  相似文献   
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Seven hundred three members of the Society for Industrial and Organizational Psychology indicated agreement or disagreement with 49 propositions regarding cognitive ability tests in organizations. There was consensus that cognitive ability tests are valid and fair, that they provide good but incomplete measures, that different abilities are necessary for different jobs, and that diversity is valuable. Items dealing with the unique status of cognitive ability were most likely to generate polarized opinions. A 2-factor model, classifying items as those reflecting societal concerns over the consequences of ability testing and those reflecting an emphasis on the unique status of "g," fit the data well, and these factors proved especially important for predicting responses to the more controversial items. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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An inulin syrup made from Jerusalem artichoke tubers, either in its commercial form or after ultrafiltration, was freeze-dried and used as a prebiotic ingredient in the small-scale manufacture of wafer crackers. The flours used for the preparation of wafer batters were from wheat, rye or spelt wheat, or 1:1 combinations of wheat flour and rye flour or wheat flour and spelt wheat flour. Batter viscosity was strongly influenced by the selection of the flour type, but remained within technologically acceptable limits. The ultrafiltration of the inulin syrup, using a 1 kDa membrane, resulted in a significant reduction of the content of free sugars and minerals which, in turn, had a significant impact on the CIE-Lab color values of the wafer crackers. Using spelt wheat flour instead of wheat flour significantly increased wafer cracker firmness measured by penetration, as did the incorporation of ultrafiltered freeze-dried instead of native freeze-dried Jerusalem artichoke syrup. Sensory analysis revealed a significant influence of product formulation on appearance, flavor and texture of the wafer crackers. It can be concluded from quality scores, which were calculated by using weighting factors assigned to the sensory attributes, that wheat flour may be partially replaced by rye flour or spelt wheat flour without negatively affecting the sensory properties of the wafer crackers.  相似文献   
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