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261.
One of the most important topics in manufacturing industries is the evaluation of performance lifetimes of products. Based on a given lifetime performance index, this paper deals with evaluating the performance of a process subject to a given lower specification limit. We confine ourselves to the progressively first-failure-censored data coming from a common Pareto distribution. With both the Bayesian and the non-Bayesian approaches being investigated here, we pay more attention to Bayesian estimators under balanced type loss functions. The results are presented under the balanced versions of two well-known loss functions, namely the squared error loss and the Varian's linear-exponential (LINEX) loss. Moreover, based on the Bayesian and the non-Bayesian approaches, the problem of testing hypotheses on the lifetime performance index is studied. Also, a simulation study is performed to assess the obtained results. Finally, two illustrative examples are given.  相似文献   
262.
In statistical process control applications, profiles functions are considered an efficient way of representing quality of products or processes. Classical and Bayesian thoughts are two chief sources of defining control charting structures for profiles monitoring. This Study introduces novel Bayesian CUSUM control structures for profiles monitoring. The comprehensive comparative study identifies that the proposed Bayesian CUSUM control charts under conjugate priors has better expected performance than competing methods. The implementation of Bayesian structures requires detailed information about process parameters which come up with considerable benefits. In addition, simulative example and case study further justified the superiority of proposed techniques.  相似文献   
263.
地方院校国有资产流失是普遍存在的问题,造成这种现象的原因是管理不完善,制度不健全。当前急需制定对策,对院校国有资产加强管理。  相似文献   
264.
改革开放引发了幼儿道德教育变革的重大历史契机,幼儿道德教育逐渐摆脱政治化、成人化、教条化阴影,向幼儿的道德主体性和生活世界回归,更加注重幼儿主体价值和社会性发展意义,以培养幼儿独立人格和道德生命为重大使命。  相似文献   
265.
Action Bias and Environmental Decisions   总被引:2,自引:0,他引:2  
Individuals have a penchant for action, often for good reasons. But action bias arises if that penchant is carried over to areas where those reasons do not apply, hence is nonrational. Action bias is explored theoretically, and then empirically, using data from surveys of hypothetical environmental decisions. Quite apart from agency considerations, individuals like to affect outcomes when gains are reaped. Given the ability to help one of two sites, we find that decision makers choose to foster improvement rather than prevent deterioration, despite framing that makes it arbitrary which site is improved, which preserved. Strong action bias—individuals choosing to reap gains even though they must impose losses—is also observed. These concepts are related to loss aversion, status quo bias, omission bias for losses, and bright-line behavior.  相似文献   
266.
根据组织分权理论和新制度经济学有关企业理论,运用组织分权成本和收益比较的方法,对影响高技术企业组织决策权的相关因素进行分析,并针对高技术企业主要的团队工作方式下,决策权力和控制权力下放提出了相应的对策。  相似文献   
267.
This paper proposes an economic-statistical design of the EWMA chart with time-varying control limits in which the Taguchi's quadratic loss function is incorporated into the economic-statistical design based on Lorenzen and Vance's economical model. A nonlinear programming with statistical performance constraints is developed and solved to minimize the expected total quality cost per unit time. This model, which is divided into three parts, depends on whether production continues during the period when the assignable cause is being searched for and/or repaired. Through a computational procedure, the optimal decision variables, including the sample size, the sampling interval, the control limit width, and the smoothing constant, can be solved for by each model. It is showed that the optimal economic-statistical design solution can be found from the set of optimal solutions obtained from the statistical design, and both the optimal sample size and sampling interval always decrease as the magnitude of shift increases.  相似文献   
268.
针对当前国内外超高温水基钻井液滤失性及高温稳定性调控难点,新研制出抗240 ℃高温、抗盐聚合物降滤失剂HTP–1。热重分析表明,HTP–1 分子链热解温度达320 ℃以上,热稳定性强;在各种钻井液基浆中的降滤失作用评价结果表明,HTP–1 在钻井液中具有优异的抗高温(240 ℃)抗盐(饱和)、抗钙(0.5%)降滤失作用,优于国内外同类产品。通过吸附实验、粒度分布测量、胶体稳定性测试和泥饼压缩性测试等手段,探讨了HTP–1 的降滤失作用机理:(1)在粘土颗粒上的吸附量大且吸附牢固,受矿化度、pH 值和温度的影响小;(2)老化(240 ℃/16 h)前后均能明显改善泥饼可压缩性,降低其渗透率;(3)增强钻井液体系的胶体稳定性,改善其中的颗粒粒径级配。  相似文献   
269.
This paper extends the concept of risk unbiasedness for applying to statistical prediction and nonstandard inference problems, by formalizing the idea that a risk unbiased predictor should be at least as close to the “true” predictant as to any “wrong” predictant, on the average. A novel aspect of our approach is measuring closeness between a predicted value and the predictant by a regret function, derived suitably from the given loss function. The general concept is more relevant than mean unbiasedness, especially for asymmetric loss functions. For squared error loss, we present a method for deriving best (minimum risk) risk unbiased predictors when the regression function is linear in a function of the parameters. We derive a Rao–Blackwell type result for a class of loss functions that includes squared error and LINEX losses as special cases. For location-scale families, we prove that if a unique best risk unbiased predictor exists, then it is equivariant. The concepts and results are illustrated with several examples. One interesting finding is that in some problems a best unbiased predictor does not exist, but a best risk unbiased predictor can be obtained. Thus, risk unbiasedness can be a useful tool for selecting a predictor.  相似文献   
270.
宁德市供电企业已全面完成改制,初步实现集约化管理。本文结合宁德市县级供电企业的现状,对提高电力市场占有率,内部加强用电管理,建立成本核算运作机制进行思考和探索,以提高县级供电企业经营效益,从而达到宁德供电企业快速发展的目的。  相似文献   
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