Monitoring Variability and Analyzing Multivariate Autocorrelated Processes

Traditional multivariate quality control charts are based on independent observations. In this paper, we explain how to extend univariate residual charts to multivariate cases and how to combine the traditional statistical process control (SPC) approaches to monitor changes in process variability in a dynamic environment. We propose using Alt's (1984) W chart on vector autoregressive (VAR) residuals to monitor the variability for multivariate processes in the presence of autocorrelation. We study examples jointly using the Hotelling T² chart on VAR residuals, the W chart, and the Portmanteau test to diagnose the types of shift in process parameters.     

关于私营企业主入党问题的思考

私营企业主中的优秀分子可以入党。私营企业主阶层是一个具有社会进步性的利益群体 ,对建设社会主义伟业和应对激烈的国际竞争具有重要作用 ;私营企业主入党不会改变党的性质 ,要摈弃对其关门主义的态度 ;私营企业主入党问题具有明显的可操作性。     

中介语可变性的文体研究

中介语是二语习得理论的重要部分,关于中介语的研究在语言学界引起了巨大的反响。可变性是中介语固有的属性,近几年来学者们从各个方面展开对中介语可变性的研究。文章分析了中介语、中介语的可变性及其研究,通过描述语言习得者所使用的语言的文体特征来证明中介语的可变性。     

Modeling Human Interindividual Variability in Metabolism and Risk: The Example of 4-Aminobiphenyl

We investigate, through modeling, the impact of interindividual heterogeneity in the metabolism of 4-aminobiphenyl (ABP) and in physiological factors on human cancer risk: A physiological pharmacokinetic model was used to quantify the time course of the formation of the proximate carcinogen, N-hydroxy-4-ABP and the DNA-binding of the active species in the bladder. The metabolic and physiologic model parameters were randomly varied, via Monte Carlo simulations, to reproduce interindividual variability. The sampling means for most parameters were scaled from values developed by Kadlubar et al. (Cancer Res., 51 : 4371, 1991) for dogs; variances were obtained primarily from published human data (e.g., measurements of ABP N-oxidation, and arylamine N-acetylation in human liver tissue). In 500 simulations, theoretically representing 500 humans, DNA-adduct levels in the bladder of the most susceptible individuals are ten thousand times higher than for the least susceptible, and the 5th and 95th percentiles differ by a factor of 160. DNA binding for the most susceptible individual (with low urine pH, low N-acetylation and high N-oxidation activities) is theoretically one million-fold higher than for the least susceptible (with high urine pH, high N-acetylation and low N-oxidation activities). The simulations also suggest that the four factors contributing most significantly to interindividual differences in DNA-binding of ABP in human bladder are urine pH, ABP N-oxidation, ABP N-acetylation and urination frequency.     

Estimating the Predicted Environmental Concentration of the Residues of Veterinary Medicines: Should Uncertainty and Variability Be Ignored?

European directives require that all veterinary medicines be assessed to determine the harmful effects that their use may have on the environment. Fundamental to this assessment is the calculation of the predicted environmental concentration (PEC), which is dependent on the type of drug, its associated treatment characteristics, and the route by which residues enter the environment. Deterministic models for the calculation of the PEC have previously been presented. In this article, the inclusion of variability and uncertainty within such models is introduced. In particular, models for the calculation of the PEC for residues excreted directly onto pasture by grazing animals are considered and comparison of deterministic and stochastic results suggest that uncertainty and variability cannot be ignored.     

百年中国报告文学语言体式的趋态、特征与基调

作为凸显体裁的语言要素,中国报告文学的语言体式于百年发展中,呈现出由早期的外指性叙述语体走向外指性叙述语体与内指性叙述语体及其它形式语体相兼容的语域变异之总体趋态。它还显现出开放性与不确定性特征,以及以写实、简洁、谨严为基点,辅以雄浑、悲壮和明朗、绚丽两种添色的语体基调。     

基于Markov链的社员与合作社系统平稳运行分析

近年来,农业合作社发展迅速,成为农民联合起来办大事、增产增收的重要平台。这里将社员与合作社看做一个系统,选取影响社员与合作社系统平稳运行的八个关键因素,画出因素间的网络结构关系图,根据Markov链理论得出网络结构关系图的邻接矩阵和Markov链的转移概率矩阵,最后通过计算得到该Markov链的平稳分布,并根据平稳分布结果,给出合理解释和相关建议。     

长效钙离子拮抗剂对动态血压季节性变异的研究

目的探讨苯磺酸氨氯地平片对动态血压季节性变异的影响。方法 96名轻中度原发性高血压患者随机分为3组,即非洛地平缓释片组（F组）、硝苯地平控释片（X组）和苯磺酸氨氯地平片（A组）,每组32例患者,所有患者用安慰剂洗脱2周后分别给予非洛地平缓释片5mg/d、硝苯地平控释片30mg/d和苯磺酸氨氯地平片5mg/d治疗,1月后血压未达标加用贝那普利片10mg/d。所有患者均于冬季和夏季分别行24小时动态血压监测,观察血压晨峰（MBPS）和冬夏两季血压达标率变化。结果无论24小时、日间还是夜间,冬季A组血压达标率（78.1%,78.1%,75.0%）均明显高于F组（62.5%,65.6%,56.3%）和X组（65.6%,68.8%,65.6%）（均P〈0.01）。冬季A组MBPS（33.7±9.7mmHg）显著低于F组（38.0±11.4mmHg,P〈0.01）和X组（36.9±10.9mmHg,P〈0.05）。结论与非洛地平缓释片和硝苯地平控释片比较,苯磺酸氨氯地平片降低血压季节性变异更明显,冬季24小时动态血压达标率更高。     

Strategic Choice of Variability in Multiround Contests and Contests with Handicaps

Variability can be an important strategic variable in a contest. We study optimal strategies involving choice of variability in contests with fixed and probabilistic targets, one-round and multiround contests, contests with and without handicaps, and situations where one contestant can modify variability as well as those in which all contestants have this opportunity. A contestant should maximize variability in a weak position (low mean, high handicap, or low previous performance) and minimize variability in a strong position. In some cases, only these extremes should be used. In other cases, intermediate levels of variability are optimal when the contestant's position is neither too weak nor too strong.     

论应对入世的五大关系——兼析认识WTO的若干误区

本文着眼于中国入世后经济生活面临的新形势、新环境、新任务和新要求,比较系统地分析了应对入世工作中面对与应对、权利与义务、改革与开放、开放与安全、内需与外需五大关系。辩证地分析各对关系中博弈与共赢的内在联系、实质内涵、现实影响及认识上的误区。