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91.
Concurrent engineering has been widely accepted as a viable strategy for companies to reduce time to market and achieve overall cost savings. This article analyzes various risks and challenges in product development under the concurrent engineering environment. A three‐dimensional early warning approach for product development risk management is proposed by integrating graphical evaluation and review technique (GERT) and failure modes and effects analysis (FMEA). Simulation models are created to solve our proposed concurrent engineering product development risk management model. Solutions lead to identification of key risk controlling points. This article demonstrates the value of our approach to risk analysis as a means to monitor various risks typical in the manufacturing sector. This article has three main contributions. First, we establish a conceptual framework to classify various risks in concurrent engineering (CE) product development (PD). Second, we propose use of existing quantitative approaches for PD risk analysis purposes: GERT, FMEA, and product database management (PDM). Based on quantitative tools, we create our approach for risk management of CE PD and discuss solutions of the models. Third, we demonstrate the value of applying our approach using data from a typical Chinese motor company. 相似文献
92.
在对Z大学中德合作2+3项目留德学生访谈的基础上,以差异性分析为视角,从教学组织、专业学习和校园生活三个纬度,分析了项目学生对两校园学习的差异性体验,并从文化价值、教育体制、教育投入方面探究其原因,提出了强化国际合作、提升师资能力水平、加大工程实训领域投入等对策。 相似文献
93.
兼并效应与产品覆盖策略 总被引:13,自引:1,他引:13
在行业寡头垄断竞争中, 引入产品覆盖策略竞争的变量, 把企业兼并时的竞争假定为两
个阶段两种变量: 先是产品覆盖策略竞争, 后是产品产量竞争, 并设计了一个描述这种兼并竞
争的模型. 在此基础上, 分析了参与和未参与兼并的企业的产品覆盖策略变化对各企业利润和
价格的影响, 在一定程度上解释了兼并悖论. 我们赞成适度的兼并控制政策, 但在经济萧条时
期可适当放宽. 相似文献
94.
Residential building codes intended to promote health and safety may produce unintended countervailing risks by adding to the cost of construction. Higher construction costs increase the price of new homes and may increase health and safety risks through income and stock effects. The income effect arises because households that purchase a new home have less income remaining for spending on other goods that contribute to health and safety. The stock effect arises because suppression of new-home construction leads to slower replacement of less safe housing units. These countervailing risks are not presently considered in code debates. We demonstrate the feasibility of estimating the approximate magnitude of countervailing risks by combining the income effect with three relatively well understood and significant home-health risks. We estimate that a code change that increases the nationwide cost of constructing and maintaining homes by $150 (0.1% of the average cost to build a single-family home) would induce offsetting risks yielding between 2 and 60 premature fatalities or, including morbidity effects, between 20 and 800 lost quality-adjusted life years (both discounted at 3%) each year the code provision remains in effect. To provide a net health benefit, the code change would need to reduce risk by at least this amount. Future research should refine these estimates, incorporate quantitative uncertainty analysis, and apply a full risk-tradeoff approach to real-world case studies of proposed code changes. 相似文献
95.
Some practical issues in the evaluation of heterogeneous labour market programmes by matching methods 总被引:1,自引:0,他引:1
Michael Lechner 《Journal of the Royal Statistical Society. Series A, (Statistics in Society)》2002,165(1):59-82
Summary. Recently several studies have analysed active labour market policies by using a recently proposed matching estimator for multiple programmes. Since there is only very limited practical experience with this estimator, this paper checks its sensitivity with respect to issues that are of practical importance in this kind of evaluation study. The estimator turns out to be fairly robust to several features that concern its implementation. Furthermore, the paper demonstrates that the matching approach per se is no panacea for solving all the problems of evaluation studies, but that its success depends critically on the information that is available in the data. Finally, a comparison with a bootstrap distribution provides some justification for using a simplified approximation of the distribution of the estimator that ignores its sequential nature. 相似文献
96.
Covariates and Random Effects in a Gamma Process Model with Application to Degradation and Failure 总被引:7,自引:0,他引:7
The gamma process is a natural model for degradation processes in which deterioration is supposed to take place gradually over time in a sequence of tiny increments. When units or individuals are observed over time it is often apparent that they degrade at different rates, even though no differences in treatment or environment are present. Thus, in applying gamma-process models to such data, it is necessary to allow for such unexplained differences. In the present paper this is accomplished by constructing a tractable gamma-process model incorporating a random effect. The model is fitted to some data on crack growth and corresponding goodness-of-fit tests are carried out. Prediction calculations for failure times defined in terms of degradation level passages are developed and illustrated. 相似文献
97.
通过“以学生为中心的主题教学模式”教改实验测试成绩数据和一系列调查结果的比较分析 ,说明了教学改革对于大学英语课堂教学的效果和学生学习能力的培养有着十分重要的作用 相似文献
98.
Kvaløy JT 《Lifetime data analysis》2002,8(1):35-51
A new approach for constructing tests for association between a random right censored life time variable and a covariate is proposed. The basic idea is to first arrange the observations in increasing order of the covariate and then base the test on a certain point process defined by the observation times. Tests constructed by this approach are robust against outliers in the covariate values or misspecification of the covariate scale since they only use the ordering of the covariate. Of particular interest is a test based on the Anderson-Darling statistic. This test has good power properties both against monotonic and nonmonotonic dependencies between the covariate and the life time variable. 相似文献
99.
技术路径与中国经济增长 总被引:4,自引:0,他引:4
王晋斌 《中国人民大学学报》2003,(2)
中国在改革开放进程中所采取的积极的产业政策拓展了与发达国家或地区的贸易关系,加快了外资引进的步伐。对外贸易和外资引进产生了技术的"外溢"和"干中学"效应,提高了市场的竞争程度,也促使国内企业积极去改进原有技术和开发新技术。这三个技术进步路径共同推动了企业技术的进步,促进了中国经济的增长。 相似文献
100.
国外关于社区 (neighborhood)对儿童和青少年影响的研究已有多年的历史并取得了不少成果。社区对儿童和青少年的影响效应一般从入学准备情况与学业成绩、行为和情绪问题 (包括外化的和内化的 )、性行为与生育等三个方面来研究考察。社区的结构维度大致可划分收入 /社会经济地位 (可划分为高、中、低三类 ) ,种族混杂程度 ,居民搬迁率等三个。社区对儿童和青少年的影响机制一般从机构资源、亲子关系和组织度三个角度来探讨 相似文献