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61.
香港将于一九九七年七月一日回归中国。九七前后香港法律的如何衔接,关系到香港平稳过渡的大局。九七之后香港法律的发展,关系到香港经济发展的状况。作者尝试勾划一个理论框架,作为研究、探讨香港法制发展问题的工具。 相似文献
62.
Victoria J. Dreitz James D. Nichols James E. Hines Robert E. Bennetts Wiley M. Kitchens Donald L. Deangelis 《Journal of applied statistics》2002,29(1-4):609-623
The rate of population growth ( u ) is an important demographic parameter used to assess the viability of a population and to develop management and conservation agendas. We examined the use of resighting data to estimate u for the snail kite population in Florida from 1997-2000. The analyses consisted of (1) a robust design approach that derives an estimate of u from estimates of population size and (2) the Pradel (1996) temporal symmetry (TSM) approach that directly estimates u using an open-population capture-recapture model. Besides resighting data, both approaches required information on the number of unmarked individuals that were sighted during the sampling periods. The point estimates of u differed between the robust design and TSM approaches, but the 95% confidence intervals overlapped substantially. We believe the differences may be the result of sparse data and do not indicate the inappropriateness of either modelling technique. We focused on the results of the robust design because this approach provided estimates for all study years. Variation among these estimates was smaller than levels of variation among ad hoc estimates based on previously reported index statistics. We recommend that u of snail kites be estimated using capture-resighting methods rather than ad hoc counts. 相似文献
63.
Estimation of the Pareto tail index from extreme order statistics is an important problem in many settings. The upper tail of the distribution, where data are sparse, is typically fitted with a model, such as the Pareto model, from which quantities such as probabilities associated with extreme events are deduced. The success of this procedure relies heavily not only on the choice of the estimator for the Pareto tail index but also on the procedure used to determine the number k of extreme order statistics that are used for the estimation. The authors develop a robust prediction error criterion for choosing k and estimating the Pareto index. A Monte Carlo study shows the good performance of the new estimator and the analysis of real data sets illustrates that a robust procedure for selection, and not just for estimation, is needed. 相似文献
64.
提出了三种新型微波毫米波单片电路共面传输线:V 形、椭圆形、圆形微屏蔽共面波导,假设其传播模式为纯 TEM 模并且不考虑色散,利用保角变换获得其特性阻抗的精确表达式,数值计算结果显示了不同的微屏蔽对其特性阻抗的影响。 相似文献
65.
用于电磁逆散射问题中关于未知介质分布的非线性积分方程经离散化后,其相应的矩阵方程通常是病态方程。对于病态的矩阵方程,其解或是不存在或是不唯一。这取决于该矩阵方程是超定的还是欠定的。对于这样的不适定问题,可用一些泛函方法使其转化为适定问题。文中介绍了用于电磁逆散射问题中的最小二乘方法、奇异值分解方法、正则化方法和最大熵方法,并对各种方法的优缺点给出评价。 相似文献
66.
This study assessed the convergent and discriminant validity of widely used various measures of family cohension and control using a multitrait, multi-method approach. Forty-two families, who had at least one adolescent and who were currently receiving family therapy, completed self-report measures of cohesion and control and engaged in Reiss' Card Sort Procedure. Ratings of the families' cohesiveness were also obtained from the families and their therapists. We were only partially successful in demonstrating convergent validity and discriminant validity for the family trait of cohesiveness across measures and methods, and even less so for family control. There was a general lack of relationship between self-report measures and either the therapist rating of family cohesion or the family's performance on the Card Sort Procedure. Our results cast doubt on the construct validity of some of the best measures of family functioning currently available. Implications of this are discussed. 相似文献
67.
68.
天线罩覆盖的波束近轴场 总被引:2,自引:0,他引:2
本文根据复射线法对通过介质天线罩的高斯波束场进行近轴近似分析。实空间的轴向复射线追综大大简化了计算过程,而复相位差、反射-传输系数和曲面扩散系数的进一步校正则提供了相当精确的结果。所得数字结果表明,在波束的近轴区域内为获得同样的计算精度,近轴近似法所需要的计算机时间远小于复射线追综法的时间。 相似文献
69.
The objective of this retrospective cohort study was to determine risk factors for police-reported intimate partner violence (IPV) during pregnancy among Seattle residents with a registered live birth or fetal death in Washington State. Logistic regression was used to calculate adjusted odds ratios (aOR) and 95% confidence intervals for the association between demographic, behavioral, and obstetric history risk factors and any, physical, and non-physical police-reported IPV. Significant risk factors for any police-reported IPV during pregnancy included unmarried status (aOR 2.36), public health program use (aOR 1.33), smoking or alcohol use during pregnancy (aORs 1.45 and 1.80, respectively), previous live birth (aOR 1.39), and previous spontaneous or induced abortion (aORs 1.39 and 1.34, respectively). Risk factors for physical IPV varied only slightly from those for any IPV, and fewer factors were associated with nonphysical IPV. Demographic, behavioral, and obstetric history risk factors are potential markers of IPV risk during pregnancy. 相似文献
70.
A study of the legal treatment of inter-group and intra-group homicides reveals that dispositional decisions are made on the basis of the sex and occupational prestige combinations of offender-victim pairs. Discriminant analysis of data concerning 444 defendants and 432 victims indicates that males accused of slaying females receive the most severe dispositions, while females held in the death of males are noticeably underpenalized. Final convictions are most severe for low status defendants alleged to have murdered high status victims. Contrary to earlier studies, there are no significant differences in legal treatment in terms of the racial combinations of the offender-victim pair. An interpretive approach to the legal process may explain these results: differential processing of homicides depends on the extent to which defendants and victims conform to the popular conception of violent criminality. 相似文献