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201.
针对国内一部分食品企业灌装包装生产线难以量化生产线效率的现状,提出了一套切实有效的生产线效率评估系统。通过评估设备速度V-曲线,以现代信息化技术为基础,提取出关键设备的停机记录,其中包含了停机的起始时间、终止时间、时长、分类、机台和原因等几大关键项内容,然后对内外部因素造成的各类时间损失进行准确量化评估,从而构建以总资产利用率、线毛产出率、设备综合利用率和线效率4项指标为衡量标准的一套生产线效率评估系统。本系统实现了灌装包装生产线数字化过程,整体透视出企业的综合管理能力、部门之间的协调配合能力、设备运行能力和故障处理能力。基于此数字化效率评估系统,可以分析停机成因,识别出影响生产线效率的核心要素,通过针对性的优化手段,达到提高效率的目的,实现降低成本和提高利润的业务目标。 相似文献
202.
This article reviews symmetrical global sensitivity analysis based on the analysis of variance of high-dimensional model representation. To overcome the computational difficulties and explore the use of symmetrical design of experiment (SDOE), two methods are presented. If the form of the objective function f is known, we use SDOE to estimate the symmetrical global sensitivity indices instead of Monte Carlo or quasi-Monte Carlo simulation. Otherwise, we use the observed values of the experiment to do symmetrical global sensitivity analysis. These methods are easy to implement and can reduce the computational cost. An example is given by symmetrical design of experiment. 相似文献
203.
Frédéric Ferraty 《Econometric Reviews》2016,35(2):263-292
We estimate two well-known risk measures, the value-at-risk (VAR) and the expected shortfall, conditionally to a functional variable (i.e., a random variable valued in some semi(pseudo)-metric space). We use nonparametric kernel estimation for constructing estimators of these quantities, under general dependence conditions. Theoretical properties are stated whereas practical aspects are illustrated on simulated data: nonlinear functional and GARCH(1,1) models. Some ideas on bandwidth selection using bootstrap are introduced. Finally, an empirical example is given through data of the S&P 500 time series. 相似文献
204.
Ping Yu 《Econometric Reviews》2016,35(4):586-637
In this paper, we propose two new estimators of treatment effects in regression discontinuity designs. These estimators can aid understanding of the existing estimators such as the local polynomial estimator and the partially linear estimator. The first estimator is the partially polynomial estimator which extends the partially linear estimator by further incorporating derivative differences of the conditional mean of the outcome on the two sides of the discontinuity point. This estimator is related to the local polynomial estimator by a relocalization effect. Unlike the partially linear estimator, this estimator can achieve the optimal rate of convergence even under broader regularity conditions. The second estimator is an instrumental variable estimator in the fuzzy design. This estimator will reduce to the local polynomial estimator if higher order endogeneities are neglected. We study the asymptotic properties of these two estimators and conduct simulation studies to confirm the theoretical analysis. 相似文献
205.
The autoregressive Cauchy estimator uses the sign of the first lag as instrumental variable (IV); under independent and identically distributed (i.i.d.) errors, the resulting IV t-type statistic is known to have a standard normal limiting distribution in the unit root case. With unconditional heteroskedasticity, the ordinary least squares (OLS) t statistic is affected in the unit root case; but the paper shows that, by using some nonlinear transformation behaving asymptotically like the sign as instrument, limiting normality of the IV t-type statistic is maintained when the series to be tested has no deterministic trends. Neither estimation of the so-called variance profile nor bootstrap procedures are required to this end. The Cauchy unit root test has power in the same 1/T neighborhoods as the usual unit root tests, also for a wide range of magnitudes for the initial value. It is furthermore shown to be competitive with other, bootstrap-based, robust tests. When the series exhibit a linear trend, however, the null distribution of the Cauchy test for a unit root becomes nonstandard, reminiscent of the Dickey-Fuller distribution. In this case, inference robust to nonstationary volatility is obtained via the wild bootstrap. 相似文献
206.
王亚杰 《陕西学前师范学院学报》2016,32(7):18-22
装置艺术是现代艺术的一个重要种类,其实质是“场地+材料+情感”的综合展示。幼儿园环境创设中可运用装置艺术,引导幼儿将生活中各种熟悉的材料进行拼贴组合、错置、悬空、分割、集合、叠加,以形成构成环境的装置作品。在此过程中,幼儿是创作环境的本体或参与者,主动参与改造环境,自由地取舍材料以丰富其创造性空间,从艺术陈列的视角对环境进行审美观照,从而提高幼儿的审美修养,激发幼儿的想象力、创造力,美化幼儿园的教学和生活环境,促进幼儿身心发展。 相似文献
207.
208.
Qing Li 《Journal of applied statistics》2016,43(3):441-460
In many fuzzy sets applications, fuzzy membership functions are commonly developed based on empirical or expert knowledge. The equation of a membership function is usually determined somewhat arbitrarily. This paper explores a novel membership function design method based on ordinal regression analysis. The estimated thresholds between ordinal measurement categories are applied to calculate the intersection points between fuzzy sets. These intersection points are further applied to determine the equations of the membership functions. Information distortion due to empirical guess can thus be reduced and more latent information in the fuzzy responses can therefore be captured. A case study investigating the relationship between foster mothers’ satisfaction and the foster time and information provided has been conducted in this research. The applicability and effectiveness of the proposed membership function assignment approach have been demonstrated through several case studies. 相似文献
209.
210.
“镇改市”是我国基层行政体制改革的试验,也是在新型城镇化过程中对基层行政区划改革做出的有益尝试。以构建大中小城市和小城镇协调发展的城镇化空间格局为目标指向,通过激活中小城市的发展“命脉”,改变单纯依靠经济推动乡镇发展的路径依赖,实现“农民城”向新型城镇的跨越,是中国经济发展的新探索。然而,随着改革的推进,缺位的行政规划设计、有限的乡镇管理能力、被异化的政绩观念、社会组织发育不成熟以及市民文化普及不到位等,对“镇改市”的推进造成一定程度的制约,成为“镇改市”过程中难以回避的现实问题。问题的化解离不开政策的引导、技术的支持和法治的保障,这三个维度相互联系、缺一不可,共同为“镇改市”改革的顺利实施“保驾护航”。 相似文献