工会发展与工资不平等： 美英工会的标准化工资率策略

从历史分析的角度看,工会和集体谈判对降低工资不平等有积极作用。美英两国的工会力量在过去一百年的发展中呈现出先增后降的倒U形趋势,与此同时,工资差距和收入不平等程度则呈同步反向运动。工会出于组织考虑、客观标准和工人团结的原因,在集体谈判中采用标准化工资率策略,提高了低工资者收入,压缩了工资分布范围,从而缩小了不平等程度。而我国存在集体合同覆盖率低、协商不充分等问题,为了改善我国收入不平等问题,需要进一步发挥工会在初次分配中的作用。     

Commentary: Flawed Scientific-Evidence Standards Delay Diesel Regulations

Of 188 government-monitored air toxics, diesel particulate matter (DPM) causes seven times more cancer than all the other 187 air toxics combined, including benzene, lead, and mercury. Yet, DPM is the only air toxic not regulated more stringently under the Clean Air Act, as a hazardous air pollutant (HAP). One reason is that regulators use flawed standards of scientific evidence. The article argues (1) that DPM meets all six specified evidentiary criteria, any one of which is sufficient for HAP regulation and (2) that regulators’ standards of evidence for denying HAP status to DPM (no DPM unit-risk estimate, inadequate dose-response data, alleged weak mechanistic data) err logically and scientifically, set the evidence bar too high, delay regulation, and allow 21,000 avoidable DPM deaths annually in the U.S.     

A simple evolutionary model of dormancy and dispersal in heterogeneous patches with special reference to phytophagous lady beetles: I. Stable environments

Summary A simple evolutionary model of dormancy and dispersal is presented with special reference to phytophagous lady beetles. In order to investigate spatially heterogeneous environments, we assume the simplest patch structure, that is, there are only two patches, main and sub. Environments are also assumed to be temporally constant. The main patch is superior to the sub patch, but density effect at the main patch is higher than at the sub patch. Optimal dormancy and dispersal are obtained at the same time by the method of evolutionarily stable strategy (ESS). In the univoltine life cycle, dormancy strategy vanishes because dormant individuals do not reproduce at all but suffer from a certain mortality rate during winter hibernation. In the bivoltine life cycle, the dormancy and dispersal rates constitute a trade-off: the rates change together with a negative correlation when the mortality rate during dispersal or during winter hibernation changes. When suitability of the main patch gradually deteriorates, the optimal strategy changes as follows: neither dormancy nor dispersal is adopted at the most suitable condition, the dispersal rate is increased without dormancy in the intermediate condition, and then the dormancy rate is increased with a constant dispersal rate. We discuss the field observation data of lady beetles in the light of results of our model.     

当前传播语境下传受主体的消解与重建

以web2．0和3G手机为代表的新媒体传播中,非专业化的私人传播日益扩大,很多方面已经超越了职业传播者的影响,传统意义上的传播者和受众的概念正在模糊化和彼此消解。这对传播的社会影响肯定会带来一系列新的问题。传统的新闻传播者要充分认识网络传播环境的特点,把传统优势和网络特征结合起来,在网络传播时代重建自己的话语主导权。     

尼尔基水利枢纽工程粘性土分散性分析的研究

尼尔基水利枢纽位于黑龙江省与蒙古交界的嫩江干流上,工程基础可能存在分散性粘土。由于分散粘土对水利工程的危害极大,有必要对该工程使用的土料进行分散性鉴定。本文通过三种试验方法鉴定得出统一结论,判定该批土样为非分散性土。     

湍流模型和施密特数对街谷内污染扩散模拟的影响

选取不同的湍动施密特数,分别采用标准κ-ε模型和realizable κ-ε模型对孤立街道峡谷内的气流运动和污染物扩散进行了数值模拟.计算得到的气流速度场和污染物浓度分布表明,标准κ-ε模型和realizable κ-ε模型预测出极为相似的气流旋涡结构,即在峡谷内生成一个中心大致位于峡谷中央的顺时针大旋涡,并在此大旋涡的作用下污染物往峡谷的背风侧积聚.通过对比分析峡谷迎风面和背风面上的无量纲污染物浓度计算结果与风洞试验数据表明,湍动施密特数的改变并不影响计算空气流场,但改变污染物扩散方程中的湍动扩散率,增大湍动施密特数将减弱污染物的湍动扩散作用,使得峡谷顶部污染物外溢减少,从而导致峡谷内的污染物浓度计算值增大;只要给定合适的计算参数,标准κ-ε模型和realizable κ-ε模型均能预测出峡谷内的污染物扩散分布,标准κ-ε模型合适的湍动施密特数为0.4～0.6,而realizable κ-ε模型则为0.3～0.5;当取湍动施密特数为0.7(Fluent软件系统中的默认值)时,标准κ-ε模型的计算精度高于realizable κ-ε模型的计算精度.     

Error rates in classification consisting of discrete and continuous variables in the presence of covariates

We consider classifying an object based on mixed continuous and discrete variables between two populations. Mixed discrete and continuous covariates with identical means in both populations are amongst the variables. Under the location model with homogeneous location specific conditional dispersion matrices for both populations, the Bayes rule is given. Classification is implemented by a plug-in version of the Bayes rule with full covariate adjustment. An asymptotic expansion of the overall expected error of the procedure is derived. Our findings generalize several classical results.     

中国的贸易开放与工资收入差距:来自制造业细分行业的经验研究

运用中国制造业细分行业1993—2009年间的面板数据,研究了贸易开放对行业间工资收入差距的影响。研究结果显示,随着中国贸易开放的不断深入,行业间工资收入不平等呈现出逐步扩大的趋势,这与传统贸易理论对发展中国家相对工资差距的预测是不一致的。从要素密集度的层面来看,对于资本密集型行业来说,相对于其他行业,进出口总额扩大了行业间的收入不平等,而出口变量的影响不明显;对于技术密集型行业来说,相对于其他行业,进口与出口都扩大了行业间的收入不平等。     

有限磁场下等离子体填充的波纹波导中波传播理论

给出了有限磁场下波在等离子体填充的波纹波导中传播的分析理论。推导出作为普遍严格公式的场分量的弗洛奎展式、本征值表达式以及色散方程。在某些特定情况下，详细讨论了波传输功率和耦合系数，这对于波纹结构的进一步研究非常有用。同时给出了初步的数值计算。其结果表明外加磁场的场强对波传播的色散特性有很大的影响从而影响了这类器件的性能。     

SMOOTH TESTS FOR THE BIVARIATE POISSON DISTRIBUTION

A theorem of Rayner & Best (1989) is generalised to permit the construction of smooth tests of goodness of fit without requiring a set of orthonormal functions on the hypothesised distribution. This result is used to construct smooth tests for the bivariate Poisson distribution. The test due to Crockett (1979) is similar to a smooth test that assesses the variance structure under the bivariate Poisson model; the test due to Loukas & Kemp (1986) is related to a smooth test that seeks to detect a particular linear relationship between the variances and covariance under the bivariate Poisson model. Using focused smooth tests may be more informative than using previously suggested tests. The distribution of the Loukas & Kemp (1986) statistic is not well approximated by the x²distribution for larger correlations, and a revised statistic is suggested.