卫星光通信中平台抖动补偿技术研究

以卫星光通信系统为例,对空间光通信系统中光学平台的抖动进行了分析。研究了一种自调节前馈补偿技术,通过自适应信号处理或对前馈控制器进行直接优化,可对光学平台的抖动进行有效抑制。     

Reliability of global sensitivity indices

Uncertainty and sensitivity analysis is an essential ingredient of model development and applications. For many uncertainty and sensitivity analysis techniques, sensitivity indices are calculated based on a relatively large sample to measure the importance of parameters in their contributions to uncertainties in model outputs. To statistically compare their importance, it is necessary that uncertainty and sensitivity analysis techniques provide standard errors of estimated sensitivity indices. In this paper, a delta method is used to analytically approximate standard errors of estimated sensitivity indices for a popular sensitivity analysis method, the Fourier amplitude sensitivity test (FAST). Standard errors estimated based on the delta method were compared with those estimated based on 20 sample replicates. We found that the delta method can provide a good approximation for the standard errors of both first-order and higher-order sensitivity indices. Finally, based on the standard error approximation, we also proposed a method to determine a minimum sample size to achieve the desired estimation precision for a specified sensitivity index. The standard error estimation method presented in this paper can make the FAST analysis computationally much more efficient for complex models.     

A simple algorithm for calculating values for folded normal distribution

Folded normal distribution originates from the modulus of normal distribution. In the present article, we have formulated the cumulative distribution function (cdf) of a folded normal distribution in terms of standard normal cdf and the parameters of the mother normal distribution. Although cdf values of folded normal distribution were earlier tabulated in the literature, we have shown that those values are valid for very particular situations. We have also provided a simple approach to obtain values of the parameters of the mother normal distribution from those of the folded normal distribution. These results find ample application in practice, for example, in obtaining the so-called upper and lower α-points of folded normal distribution, which, in turn, is useful in testing of the hypothesis relating to folded normal distribution and in designing process capability control chart of some process capability indices. A thorough study has been made to compare the performance of the newly developed theory to the existing ones. Some simulated as well as real-life examples have been discussed to supplement the theory developed in this article. Codes (generated by R software) for the theory developed in this article are also presented for the ease of application.     

Linear estimation for the extended exponential power distribution

Tiao and Lund [The use of OLUMV estimators in inference robustness studies of the location parameter of a class of symmetric distributions. J Amer Statist Assoc. 1970;65(329):370–386] tabulated the coefficients of the best linear unbiased estimators (BLUEs) of location and scale for a particular family of symmetric distributions. This family was a reparameterization of the extended exponential power distribution (EEPD) with the shape parameter restricted to be greater than or equal to one. In this work, we consider the BLU estimation of the location and scale parameters of the EEPD when the shape parameter is one-third and one-half. We obtain closed-form expressions for the single and product moments of the order statistics when the shape parameter is in general in the form of a reciprocal of an integer. These expressions are then used to determine the BLUEs and the corresponding variances for complete samples of size 20 and less. We consider some other linear estimators of the location and scale parameters and then compare them with the BLUEs. Finally, we present a numerical example to illustrate the developed results.     

On the improvement of one-sided S control charts

The most common charting procedure used for monitoring the variance of the distribution of a quality characteristic is the S control chart. As a Shewhart-type control chart, it is relatively insensitive in the quick detection of small and moderate shifts in process variance. The performance of the S chart can be improved by supplementing it with runs rules or by varying the sample size and the sampling interval. In this work, we introduce and study one-sided adaptive S control charts, supplemented or not with one powerful runs rule, for detecting increases or decreases in process variation. The properties of the proposed control schemes are obtained by using a Markov chain approach. Furthermore, a practical guidance for the choice of the most suitable control scheme is also provided.     

最低工资标准与和谐劳动关系的构建——广州、佛山、深圳最低工资标准比较研究

最低工资保障问题是构建和谐劳动关系的核心内容和难点问题。对广州、佛山和深圳最低工资标准现状进行分析,并运用ELES模型测算其最低工资标准,测算结果显示：目前三市最低工资实际标准与理论标准仍有差距,其中广州的差距最小,佛山次之,深圳的差距最大;最低工资标准与职工平均工资比例偏低,与人均GDP比例关系失调,深圳最低工资执行标准总体优于广州和佛山。鉴此,提出应以发展线水平为目标制定最低工资标准等建议。     

严复“信达雅”翻译标准及其哲学认知

翻译中"信达雅"的标准多年来一直引起人们的争论,如何正确理解其内涵是人们所关注的重点。严复提出的"信达雅"翻译标准在中国翻译史上的重要地位值得肯定。应该用哲学的辩证统一的观点来理解"信达雅"原则。"信"和"达"是基础,"信"得贴切,"达"得恰当,便产生"雅"的风格、"雅"的神韵。三者相互依存、相互制约、水乳交融、密不可分。     

国际海事惯例及其司法识别问题研究

国际航运业的发展源远流长,中国自改革开放以来逐步构建起了中国特色社会主义海商法律体系。作为法律体系补充的国际海事惯例日益受到重视,将国际海事惯例运用到国内司法活动的前置问题就是司法识别。司法识别包括程序方面的构造和实体方面的标准两大方面,程序构造和实体标准相辅相成、相得益彰,共同构成了国际海事惯例司法识别问题的完整体系。从宏观角度对国际海事惯例的司法识别问题进行制度化完善,将有利于其科学规范的适用,为航运业的健康和可持续发展提供强有力保障。     

试论精神损害赔偿

精神损害赔偿一直是学界和司法界关注的热点和难点,也是进一步完善我国法律制度必须要解决的课题之一。确立并完善精神损害制度,是出自维护权利的需要,也是权利人维护自身精神利益的必然前提。我国精神损害赔偿的法律依据是《民法通则》及最高人民法院的相关司法解释,但是对于精神损害赔偿的规定显得不够具体和完善。笔者将就该问题谈谈个人的看法。