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11.
线性分式目标规划是近几年发展起来的目标规划的新分支,尚无一般解法。本文给出了混合线性分式目标规划的一般解法及其应用实例。  相似文献   
12.
本文介绍了人机工程学(工效学)这一新兴边缘学科的研究内容、发展及现状,讨论了人-机系统的可靠性并着重讨论了人的操作可靠性,探讨了按人为差错进行可靠性分析与可靠性估计的人为差错和可靠性分析逻辑推演法(HERALD法)及系统能力方法(SC方法)。 本文的结论可供系统管理工作者及设计工作者,特别是可靠性管理及可靠性设计工作者参考。  相似文献   
13.
Nonlinear mixed-effects (NLME) models are flexible enough to handle repeated-measures data from various disciplines. In this article, we propose both maximum-likelihood and restricted maximum-likelihood estimations of NLME models using first-order conditional expansion (FOCE) and the expectation–maximization (EM) algorithm. The FOCE-EM algorithm implemented in the ForStat procedure SNLME is compared with the Lindstrom and Bates (LB) algorithm implemented in both the SAS macro NLINMIX and the S-Plus/R function nlme in terms of computational efficiency and statistical properties. Two realworld data sets an orange tree data set and a Chinese fir (Cunninghamia lanceolata) data set, and a simulated data set were used for evaluation. FOCE-EM converged for all mixed models derived from the base model in the two realworld cases, while LB did not, especially for the models in which random effects are simultaneously considered in several parameters to account for between-subject variation. However, both algorithms had identical estimated parameters and fit statistics for the converged models. We therefore recommend using FOCE-EM in NLME models, particularly when convergence is a concern in model selection.  相似文献   
14.
This paper is the generalization of weight-fused elastic net (Fu and Xu, 2012 Fu, G., Xu, Q. (2012). Grouping variable selection by weight fused elastic net for multi-collinear data. Communications in Statistics-Simulation and Computation 41(2):205221.[Taylor & Francis Online], [Web of Science ®] [Google Scholar]), which performs group variable selection by combining weight-fused LASSO(wfLasso) and elastic net (Zou and Hastie, 2005 Zou, H., Hastie, T. (2005). Regularization and variable selection via the elastic net. Journal of the Royal Statistical Society: Series B (Statistical Methodology) 67(2):301320.[Crossref], [Web of Science ®] [Google Scholar]) penalties. In this study, the elastic net penalty is replaced by adaptive elastic net penalty (AdaEnet) (Zou and Zhang, 2009 Zou, H., Zhang, H. (2009). On the adaptive elastic-net with a diverging number of parameters. Annals of Statistics 37(4):17331751.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]), and a new group variable selection algorithm with oracle property (Fan and Li, 2001 Fan, J., Li, R. (2001). Variable selection via nonconcave penalized likelihood and its oracle properties. Journal of the American Statistical Association 96(456):13481360.[Taylor & Francis Online], [Web of Science ®] [Google Scholar]; Zou, 2006 Zou, H. (2006). The adaptive lasso and its oracle properties. Journal of the American Statistical Association 101(476):14181429.[Taylor & Francis Online], [Web of Science ®] [Google Scholar]) is obtained.  相似文献   
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In this note, a probabilistic method for predicting the future total net basal area of closed uneven-aged stand based on “Stand Tally” is proposed and an example is given.  相似文献   
17.
语言学家奥斯汀在他的言语行为理论中把施为句分成三种:以言指事、以言行事和以言成事。我们借用奥斯汀的以言指事之称,认为语言中的禁忌语也是“言有所指”,指代的是客观世界中人们所避讳的事物和理念,因此被禁忌。禁忌语的“言有所指”大致可以分为人称代词指称语类、专有名词指称语类、普通名词指称语类三个类别。人们之所以禁忌这些言语,是混淆了“能指”和“所指”之间的关系。  相似文献   
18.
傅崇兰 《城市》2007,(7):3-6
2006年12月,胡锦涛总书记在中央经济工作会议上提出:"在做好陆地规划的同时,要加强海洋意识,做好海洋规划,完善体制机制,加强各项工作,从政策和资金上扶持海洋经济的发展."  相似文献   
19.
Fu  Yelin  Sui  Yubing  Luo  Hao  Han  Biao 《Social indicators research》2020,148(3):1005-1019
Social Indicators Research - As a new composite indicator for capturing the value delivered by health systems of developing and developed economies, the Value Measure is the arithmetic average of...  相似文献   
20.
We study equilibrium player ordering in a dynamic all-pay contest between two teams. The contest lasts two periods, and each team consists of two players who perform in different periods on behalf of their teams. The team with the higher aggregate output wins the prize, which is a public good to its players. Each team has one stronger player and one weaker player, and the two teams can differ in their values of the prize. The teams maximize their winning odds by strategically assigning their players to different periods. We find that when the intrateam heterogeneity in player ability is not excessive, the teams would allocate their stronger players to the late positions as the “anchormen.” When both the intrateam ability gap and interteam heterogeneity in teams' values become excessively large, the team with high value always places its stronger player in the early position, who will place a large bid to preempt late competition. (JEL C7, D7, D8)  相似文献   
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