基于GMPLS的光突发交换的研究

基于通用多协议标签交换的光突发交换是目前的网络发展趋势,而突发汇聚是它的非常关键的技术。利用通用多协议标签交换中的标签转发路径汇聚与信令协议(为适应光突发交换而有所修改)来实现突发汇聚,并对网络流量工程和数据的保护与恢复作了一些探讨。最后,给出基于通用多协议标签交换的光突发交换所带来的优势。     

中国省域人口总数修订

人口统计数据是制定宏观经济政策和规划人口发展的基础。中国非普查年度人口总数常常与普查年度人口总数差异较大,而关于中国非普查年度人口统计数据修订的研究较少。建立省域人口增长率的固定效应模型,描述中国各省域人口总数的变化趋势,基于拟合模型和普查数据,提出中国省域人口总数修订方法,并对2001年至2009年中国省域人口总数进行修订,结果表明:2001年至2009年中国人口总数修订值与《中国统计年鉴》公布的人口总数之间存在差异,差异率低于0.5%;省域人口总数修订值变化相对平稳,在年度之间的变化幅度相对小,能够更合理反映各省域人口总数的发展趋势。     

论教师语言的特点

教师的语言素养对教师有着特殊的意义。要提高课堂教学水平,教师语言能力的提高是非常重要的环节。一般来说,教师的语言应具备艺术性、准确性、亲切性和启发性等特点。     

Flexible manufacturing systems performance in U.S. automotive manufacturing plants: a case study

Flexible manufacturing systems (FMS) philosophy is a key weapon in achieving global manufacturing competitiveness. It encompasses a wide range of dimensions to improve all aspects of operational performance metrics. The aim of the study is to examine the current state of flexibility adoption in U.S. automotive manufacturing facilities and its impact on operational performance metrics. It utilizes survey questionnaire developed based on previous work in U.S. manufacturing industry. The survey was originally distributed to 420 facility managers in the U.S. domestic automotive industry. It was revealed that 70% of the respondents had implemented all 15 flexibility dimensions listed in the questionnaire. The data analysis conducted shows that implementation of certain flexibility dimensions will lead to significant improvement in specific operational performance metrics. This considerable finding can be used as a guide for manufacturing managers to achieve certain objectives in operational performance improvement in a rapidly changing environment.     

同步物流系统下准时化生产与配送调度问题研究

对于"加工-装配"行业而言,物流管理水平的高低直接决定了供应链绩效的好坏。本文以Supply Hub运作模式为背景,研究同步物流下装配系统中各节点的生产与配送调度问题。建立供应链各参与方的生产与配送模型,并通过规划求解得到供应商和制造商的最优生产周期、零部件的最优配送间隔以及零售商的最佳采购周期。最后,结合数值实验,对同步物流模式和传统物流模式下的供应链绩效进行了对比分析。研究结果表明:较之传统物流模式,基于同步化物流方式的装配系统总成本更低,这主要得益于库存成本的下降;由于采取拉动式的生产模式,因此同步物流系统下供应链中的生产和配送活动更加频繁;生产调整成本的增加提高了制造商的平均总成本,由此可见在同步物流系统下,供应商、制造商和零售商之间更需要相互协商和收益共享,从而实现多赢。     

Unraveling the Source of African American Children's Positively Biased Perceptions of Peer Acceptance

The present study investigated possible ethnic contributions to overly positive self‐perceptions in middle childhood. The goals of this study were threefold. First, the present study sought to replicate the intriguing findings reported by Zakriski and Coie that African American children overestimate their acceptance, and European American children underestimate acceptance by other‐ethnicity peers. Second, this study examined possible explanations for ethnic differences in the pattern of perceptual bias. Finally, this study extended prior research by examining ethnic differences in the accuracy of children's perceived peer acceptance. Archival data consisting of 826 children in third (N = 284), fourth (N = 241), and fifth grades (N = 301) were used in the present investigation; 237 of which were African American children, and 589 were European American children. Results of this study replicated the findings of Zakriski and Coie . Moreover, African Americans' overestimation and European Americans' underestimation of acceptance by other‐ethnicity peers was found to be attributable to more positive views of self and others among African American children relative to European American children. Finally, children were found to be more accurate about judging their acceptance by peers of the same ethnicity than those of a different ethnicity. Possible explanations of what causes African American children to have more positive views of self and others than European American children are discussed.     

Empathic Accuracy and Aggression in Couples: Individual and Dyadic Links

The authors examined links between intimate partner aggression and empathic accuracy—how accurately partners can read one another's emotions—during highly affective moments from couples' (N = 109) video recall of laboratory‐based discussions of upsetting events. Less empathic accuracy between partners was generally related to higher levels of aggression by both partners. More specific patterns emerged based on the type of aggression and emotion being expressed. Women's poorer ability to read their partners' vulnerable and positive emotions was linked to both men's and women's greater physical and psychological aggression. Moreover, women's inaccuracy in reading their partner's hostility was linked to women's greater psychological aggression toward the men. Men's inaccuracy in reading their partner's hostility was linked to women's (not men's) greater physical and psychological aggression. The results suggest important nuances in the links between empathic inaccuracy and aggression, and implications for prevention and treatment of partner aggression are discussed.     

Validation of qualitative microbiological test methods

This paper considers a statistical model for the detection mechanism of qualitative microbiological test methods with a parameter for the detection proportion (the probability to detect a single organism) and a parameter for the false positive rate. It is demonstrated that the detection proportion and the bacterial density cannot be estimated separately, not even in a multiple dilution experiment. Only the product can be estimated, changing the interpretation of the most probable number estimator. The asymptotic power of the likelihood ratio statistic for comparing an alternative method with the compendial method, is optimal for a single dilution experiment. The bacterial density should either be close to two CFUs per test unit or equal to zero, depending on differences in the model parameters between the two test methods. The proposed strategy for method validation is to use these two dilutions and test for differences in the two model parameters, addressing the validation parameters specificity and accuracy. Robustness of these two parameters might still be required, but all other validation parameters can be omitted. A confidence interval‐based approach for the ratio of the detection proportions for the two methods is recommended, since it is most informative and close to the power of the likelihood ratio test. Copyright © 2014 John Wiley & Sons, Ltd.     

Reflections on Accuracy

The difference between test accuracy and predictive accuracy is presented and defined. The failure to distinguish between these two types of measures is shown to have led to a misguided debate over the interpretation of prevalence estimates. The distinction between test accuracy defined as sensitivity and specificity, and predictive accuracy defined as positive and negative predictive value is shown to reflect the choice of the denominator used to calculate true positive, false positive, false negative, and true negative rates. It is further shown that any instrument will tend to overestimate prevalence in low base rate populations and underestimate it in those populations where prevalence is high. The implications of these observations are then discussed in terms of the need to define diagnostic thresholds that have clinical and policy relevance.     

英语学习者朗读错误对比分析

不同水平的英语学习者在朗读中的各类错误方面存在差异。高水平组在准确性错误中的增减音、重音误置、错词方面显著少于低水平组;而在流利性错误中的重复、修补、不当停顿方面,两组之间无显著差异。高水平组中,只有错音和修补有显著区别;低水平组中,只有重音误置和修补、加减词和错音有显著区别。