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51.

This paper is concerned with the optimization of tool requirements in flexible manufacturing systems (FMSs). The main aim is to determine the best tool spectrum (i.e. the number of duplicates for each tool type to be provided) considering different layouts of the tool management area (tool rooms). The optimization method is based on the reciprocal interaction between a genetic algorithm (GA) and the simulation model of the FMS considered. Thus, the results proposed refer to the efficacy of the technique adopted and its practical application to tool management.  相似文献   
52.
《Adoption quarterly》2013,16(1):5-11
Abstract

Dr. Paul Denhalter completed his doctoral candidacy research on adoptive family attachment and entitlement. Nineteen parents were interviewed about what elements of adoptive family life contributed to a sense of entitlement. The act of care giving increased entitlement; negative comments from others about adoption tended to decrease it. In his social work practice, Dr. Denhalter counseled adoptive and birth families and advocated education, counseling and support for successful open adoption relationships. His positive perspective on adoption included his father's adoption at age five. Dr. Denhalter was critical of the current trends in adoption that have pathologized adoption for political purposes. He emphasized the results of the Search Institute's study that had positive conclusions about adopted children as well as a blueprint for successful adoptive families to follow.  相似文献   
53.
The author considers estimation under a Gamma process model for degradation data. The setting for degradation data is one in which n independent units, each with a Gamma process with a common shape function and scale parameter, are observed at several possibly different times. Covariates can be incorporated into the model by taking the scale parameter as a function of the covariates. The author proposes using the maximum pseudo‐likelihood method to estimate the unknown parameters. The method requires usage of the Pool Adjacent Violators Algorithm. Asymptotic properties, including consistency, convergence rate and asymptotic distribution, are established. Simulation studies are conducted to validate the method and its application is illustrated by using bridge beams data and carbon‐film resistors data. The Canadian Journal of Statistics 37: 102‐118; 2009 © 2009 Statistical Society of Canada  相似文献   
54.
The estimation of the means of the bivariate normal distribution, based on a sample obtained using a modification of the moving extreme ranked set sampling technique (MERSS) is considered. The modification involves using a concomitant random variable. Nonparametric-type methods as well as the maximum likelihood estimation are considered. The estimators obtained are compared to their counterparts based on simple random sampling (SRS). It appears that the suggested estimators are more efficient. Also, MERSS with concomitant variable is easier to use in practice than the usual ranked set sampling (RSS) with concomitant variable. The issue of robustness of the procedure is addressed. Real trees data set is used for illustration.  相似文献   
55.
56.
本文考察《搜神记》《世说新语》中选择问句的格式、形式特征及在句意表达上的特点。通过对两书中这类问句的描写,从一侧面揭示出选择问句在中古汉语前期发展变化的一些情况。  相似文献   
57.
Summary. When a number of distinct models contend for use in prediction, the choice of a single model can offer rather unstable predictions. In regression, stochastic search variable selection with Bayesian model averaging offers a cure for this robustness issue but at the expense of requiring very many predictors. Here we look at Bayes model averaging incorporating variable selection for prediction. This offers similar mean-square errors of prediction but with a vastly reduced predictor space. This can greatly aid the interpretation of the model. It also reduces the cost if measured variables have costs. The development here uses decision theory in the context of the multivariate general linear model. In passing, this reduced predictor space Bayes model averaging is contrasted with single-model approximations. A fast algorithm for updating regressions in the Markov chain Monte Carlo searches for posterior inference is developed, allowing many more variables than observations to be contemplated. We discuss the merits of absolute rather than proportionate shrinkage in regression, especially when there are more variables than observations. The methodology is illustrated on a set of spectroscopic data used for measuring the amounts of different sugars in an aqueous solution.  相似文献   
58.
网络的普及使得IP地址越来越少,文章将从IP地址的角度出发,介绍一种在网络几何结构上实现网络的分组管理的方法——子网划分。  相似文献   
59.
将模拟退火算法和遗传算法、粒子群优化算法分别进行结合,形成模拟退火—遗传算法以及模拟退火—粒子群优化算法,并作性能对比分析。研究结果表明,这两种算法都在进化代数和全局寻优能力方面有较大突破,在找寻最佳个体解的效率上,模拟退火—粒子群优化算法更突出。  相似文献   
60.
本文在分析一维优化方法的比例因子法的基础上,提出了一种直接调整步长的最优步长因子法并给出框图。该法较比例因子法理论上完善,迭代控制可靠。  相似文献   
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