促性腺激素、V_(D_3)、V_E亚硒酸钠对母兔繁殖力的影响

选择成年、健康、未孕母兔 32只 ,随机分成 8组 ,分别给予促性腺激素 (Ⅰ组 )、VD3(Ⅱ组 )、VE 亚硒酸钠 (Ⅲ组 ) ,促性腺激素 +VD3(Ⅳ组 )、VD3+VE 亚硒酸钠 (Ⅴ组 )、促性腺激素 +VE 亚硒酸钠(Ⅵ组 )、促性腺激 +VD3+VE 亚硒酸钠 (Ⅶ组 ) ,空白对照 8种处理。试验结果表明 ,母兔经药物处理后 ,其繁殖性能 (发情状况、排卵数、正常受精卵数 )都比对照组显著地提高 ,但Ⅰ、Ⅳ、Ⅵ组有畸形卵子存在 ,以处理Ⅶ组效果最好 ,其排卵数达 4 7± 2 0 .3个 ,正常受精卵 35个 ,分别比对照组多 36 .5个、30个。     

文化的根本意蕴及其价值——兼论我国文化建设的合理思路

文化作为一个热点研究问题 ,理论界在许多方面存在分歧。本文着重厘清了人们对文化在概念、价值方面的误解 ,认为文化是一个标志人的主观心态和观念形态的范畴 ,是人处理其与客观世界的多重现实的对象性关系和解决人类内在精神需求的方式 ,这种方式表现为并对象化为千状万态的精神现象和产物 ,并且认为文化对人和社会的价值意义是个客观事实 ,文化的作用已深深地渗透到社会的演进过程中 ,最后从文化的价值意义出发 ,阐述了我国文化建设的合理思路。     

Empirical likelihood confidence intervals for the mean of a population containing many zero values

If a population contains many zero values and the sample size is not very large, the traditional normal approximation‐based confidence intervals for the population mean may have poor coverage probabilities. This problem is substantially reduced by constructing parametric likelihood ratio intervals when an appropriate mixture model can be found. In the context of survey sampling, however, there is a general preference for making minimal assumptions about the population under study. The authors have therefore investigated the coverage properties of nonparametric empirical likelihood confidence intervals for the population mean. They show that under a variety of hypothetical populations, these intervals often outperformed parametric likelihood intervals by having more balanced coverage rates and larger lower bounds. The authors illustrate their methodology using data from the Canadian Labour Force Survey for the year 2000.     

金属垂直安定面的后向散射分析

采用射线跟踪和等效电流等方法计算金属垂直安定面的后向散射场和后向散射截面积(RCS)。对TM入射和TE入射在不同的入射角下求得数值结果。仔细分析了外形对后向RCS的影响,并提出压缩后向RCS的措施。     

Sampling Strategies for Toxic Air Contaminants

Annual concentrations of toxic air contaminants are of primary concern from the perspective of chronic human exposure assessment and risk analysis. Despite recent advances in air quality monitoring technology, resource and technical constraints often impose limitations on the availability of a sufficient number of ambient concentration measurements for performing environmental risk analysis. Therefore, sample size limitations, representativeness of data, and uncertainties in the estimated annual mean concentration must be examined before performing quantitative risk analysis. In this paper, we discuss several factors that need to be considered in designing field-sampling programs for toxic air contaminants and in verifying compliance with environmental regulations. Specifically, we examine the behavior of SO2, TSP, and CO data as surrogates for toxic air contaminants and as examples of point source, area source, and line source-dominated pollutants, respectively, from the standpoint of sampling design. We demonstrate the use of bootstrap resampling method and normal theory in estimating the annual mean concentration and its 95% confidence bounds from limited sampling data, and illustrate the application of operating characteristic (OC) curves to determine optimum sample size and other sampling strategies. We also outline a statistical procedure, based on a one-sided t-test, that utilizes the sampled concentration data for evaluating whether a sampling site is compliance with relevant ambient guideline concentrations for toxic air contaminants.     

The sample autocorrelation function of I(1) processes

In case of a random walk the theoretical autocorrelations tend to one asymptotically. The sample autocorrelations, however, may decline rather fast even with large samples. We will explain this observation by deriving the asymptotic distribution that turns out to be closely related to the Dickey-Fuller (1979) distribution. Moreover we discuss the behaviour of the sample autocorrelations of integrated MA(1) and AR(1) processes. In order to prove our results we consider more general I(1) processes and apply the functional central limit theorem injected to time series analysis by Phillips (1987). We obtain unit root tests that are based on autocorrelation estimators of higher lags. We discuss their finite sample behaviour experimentally.     

Statistical software packages for PCs — A market survey

The increase of statistical software applications for PCs is caused by decreasing hardware costs and dramatically enhanced PC performance. Whereas in the past the domain of statistical computing has been reserved to mainframe solutions, a great number of new software packages for PCs have come out in the last five years. Therefore, the producers of established mainframe software were also forced to offer PC-based solutions. By limiting a market analysis to products with a medium set of well known statistical methods, the immense number of available products is reduced to about fifty systems. We ordered an evaluation copy of these systems to test the numerical quality, the system speed, and the performance of several procedures. Seventeen packages were made available for an extensive examination. This paper will (1) discuss the problems and the solutions of obtaining a complete and correct datamatrix that describes the entire market and (2) present the results of a comparative market analysis.     

Diet,mortality and life expectancy: a cross national analysis

"There are numerous reasons why mortality and life expectancy vary between countries. Epidemiological studies seem to indicate that dietary variations may be among them. A sample of 51 countries studied with data from the International Comparisons Project and other sources, shows that after controlling for nutrient intake, consumption of medical goods and services, income distribution, weather, and literacy, countries with more meat and poultry in their diet have lower life expectancies after age five. The results for infant mortality and child death between one and five indicate that a more animal-intensive diet may be actually beneficial, especially if fish consumption is increased and meat and poultry consumption reduced."     

Marriage and its transition in Bangladesh

The author examines developments in marriage patterns in Bangladesh in light of social, cultural, and economic conditions. Previous literature on the subject is used to discuss Muslim marriage, Hindu marriage, child marriage, mate selection and social mobility, and the question of a marriage squeeze. "The analysis presents evidence that the society is experiencing a change in its family formation, mating process and family type. This transition is to some extent towards the characteristics of [the] Western World, but in a poor economy. Part of this transition is due to the effect of modernization and part due to increasing poverty."     

Sociological aspects of migration policy: the case of the Federal Republic of Germany

In March 1980 the Federal Republic of Germany (FRG) adopted guidelines for the further development of migration policy in which the social integration of 2nd- and 3rd-generation foreigners was a priority of migration policy in the future. However, there was no corresponding information and education for the German population on the envisaged integration of foreigners. At the end of 1981 the FRG was still not a country of immigration. From 1980-1982 the pressure of public opinion to restrict the number of incoming foreigners and the latent hostility towards foreigners constantly increased. In February 1982, the Federal Government adapted the following principles for their immigration policy: 1) to limit effectively further immigration of foreigners into the FRG; 2) to strengthen the desire of foreigners to return to their native countries; and 3) to improve the economic and social integration of foreigners who have lived in the FRG for many years and to define their rights of residence more precisely. In 1982, migration policy became an important aspect of German domestic affairs. The 1st decision on migration policy taken by the Federal Government (Christian-Democrats and Liberals) was to offer financial incentives for foreigners to remigrate. An opinion poll conducted in late 1981 showed that 1/2 the German population was hostile to foreigners, 58% of Germans wanted to see the number of foreigners limited or reduced, and 62% disapproved of foreign workers being allowed to bring their families into Germany. The Remigration Assistance Act of 1983 has had the following effects: 1) foreigners have become uncertain about their plans for the future, and 2) it gives the German population the illusion that the "problem caused by foreigners" will be automatically solved by their return. Young foreigners encounter unfavorable situations in the training and employment sectors. Another obstacle in their way is hostility to foreigners. A survey in 1985 showed that most older foreigners planned to return to their native country, while most younger ones did not. It is essential for the 1-sided emphasis on remigration assistance to be abandoned in the FRG's migration policy. The commission on migration set up by the Federal Government has also emphasized that the integration of foreigners is a fundamental element of migration policy.