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61.
Nonparametric deconvolution problems require one to recover an unknown density when the data are contaminated with errors. Optimal global rates of convergence are found under the weighted Lp-loss (1 ≤ p ≤ ∞). It appears that the optimal rates of convergence are extremely low for supersmooth error distributions. To resolve this difficulty, we examine how high the noise level can be for deconvolution to be feasible, and for the deconvolution estimate to be as good as the ordinary density estimate. It is shown that if the noise level is not too high, nonparametric Gaussian deconvolution can still be practical. Several simulation studies are also presented.  相似文献   
62.
Summary The number of larvae reaching maturity within the gall ofAdelges japonicus was positively related to gall volume, and the relationship between the number of mature larvae and gall volume did not change with different densities of colonized larvae. The population changes in the bud galls ofA. japonicus were surveyed by collecting the galls, which did not suffer predation or parasitism within the galls, from young artificial plantations ofPicea jezoensis over two years. In the year when the density of colonized larvae was high, they suffered a 42% mortality within the galls, whereas mortality was nearly zero in the low density year. The numbers of larvae per gall were positively correlated with gall volume. The regression lines of the number of colonized larvae on gall volume did not differ significantly in the regression coefficients between the two years, whereas the intercept was significantly higher in the year when the density of colonized larvae was higher. However, different within-gall mortality nullified this difference, and the regression lines of the number of mature larvae on gall volume had no significant difference both in the regression coefficients and the intercepts. This suggests that the number of mature larvae per gall was limited by available resources within the gall which were positively related to gall volume. In 25% of the galls in which mature larvae inhabited, the space within the galls were completely filled by the larvae, indicating that space was one of the limiting resources. Gall volume also affected the number of adults that emerged from the gall and the potential number of their progeny.  相似文献   
63.
The robustness of Mauchly's sphericity test criterion when sampling from a mixture of two multivariate normal distributions is studied. The distribution of the sphericity test criterion when the sample covariance matrix has a non-central Wishart density of rank one is derived in terms of Meijer's G-functions; its distribution under the mixture model is then deduced. The robustness is studied by computing actual significance levels of the test under the mixture model using the critical values under the usual normal model.  相似文献   
64.
本文主要分析了HEIDENHAIN TNC 310数控铣床系统中圆弧铣削指令及螺纹铣削指令,对螺纹铣削功能进行延伸,扩展到圆弧三轴联动,并对螺纹铣削指令格式进行了修改,从而具有圆弧三轴联动铣削功能。  相似文献   
65.
Technology continues to challenge the public relations practitioner to find ways to inform key constituents. The new technology has given rise to the “new journalism” that includes a declining traditional media and exploding internet media filled with websites and bloggers. The question posed by this research asks: Does the public relations practitioner inherit the same protection offered by “qualified privilege” that is most often associated with the traditional “press” or “reporter?” The research lays a foundation with an examination of defamation and the defense of qualified privilege. The research concludes that if information gathered by the public relations practitioner meets the “intent” and “content” tests, the information qualifies as news. Passing the “news” test, the defense of “qualified privilege” also attaches to the public relations practitioner.  相似文献   
66.
In many developing regions, women and young girls spend several hours daily in the collection of natural resources. Still the link between these household resource strategies and stakeholder perceptions of development priorities remains unexplored. This project examines this association with survey data representative of the adult population from Ghana’s Coastal Region. Although natural resource scarcity and the sustainability of resource use represent key development challenges, there are others (e.g., energy, sanitation, employment, and educational opportunities). As such, even in the face of natural resource scarcity, individuals may place greater importance on other dimensions of development, especially if household resource strategies are perceived as relatively efficient. The analytical focus here is on water and the results suggest that gender roles shape household water collection strategies, while also shaping these strategies’ perceived opportunity costs. Specifically, Ghanian adults more often see drinking water provision as their primary development need when water sources are distant and/or when male household members collect water (particularly male heads). In the end, I argue that social science inquiry benefits by contextualizing social dynamics within environmental context, particularly within cultural settings in which human subsistence is intimately tied to the state of the natural environment.  相似文献   
67.
完善我国公司治理结构的路径探析   总被引:3,自引:0,他引:3  
公司治理结构在当代的发展趋势之一是利益相关者共同参与公司治理。我国公司股权集中、内部人控制严重、外部监督机制失灵的治理现状,决定了完善我国公司治理结构的有效路径应是构建利益相关者共同参与的公司治理结构,即将非股东的其他利益相关者引入公司治理,直接参与公司的经营、控制与监督。  相似文献   
68.
当代印度社会正发生着极大的变动,社会各阶层都在极力维护固有地位和宗教传统的稳定,并极力在这种变动中争取着自身社会利益的最大化。其中,南印度婆罗门种姓在逐步丧失传统的各项特权和优势地位的同时,也在努力适应、应对当代社会的新变化和新挑战。英国作家V.S.奈保尔的《印度:百万叛变的今天》一书提供了较为翔实、客观的口述史资料。以书中生活在孟买、班加罗尔、马德拉斯、加尔各达等南印度城市中的当代婆罗门阶层作为个案,可探究出其面对传统社会生活中的各个层面发生变动时的态度与应对及个体内在的深层原因,并在一定程度上考察社会变动与文化传统之间的互动关系。  相似文献   
69.
Summary.  A stochastic discrete time version of the susceptible–infected–recovered model for infectious diseases is developed. Disease is transmitted within and between communities when infected and susceptible individuals interact. Markov chain Monte Carlo methods are used to make inference about these unobserved populations and the unknown parameters of interest. The algorithm is designed specifically for modelling time series of reported measles cases although it can be adapted for other infectious diseases with permanent immunity. The application to observed measles incidence series motivates extensions to incorporate age structure as well as spatial epidemic coupling between communities.  相似文献   
70.
皮锡瑞《经学家法讲义》稿本的内容及其价值   总被引:1,自引:0,他引:1  
保存在《师伏堂经学杂记》中的一组经学文稿,是近代经学大师皮锡瑞晚年讲授"经学家法"课程时所编讲义原稿。这部《经学家法讲义》手稿对先秦至魏晋的经学变迁与得失作了简明扼要的疏理和评述,描绘出魏晋以前经学历史的基本轮廓,其中的新见卓识,更显示出这部隐秘至今的经学遗稿的学术价值。皮锡瑞还在稿中自道其"郑学"研究,有助于今人全面体认他融通今、古文经学的学术品性,确证他决非专治今文家言的经师。  相似文献   
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