Error reduction in density estimation under shape restrictions

For the problems of nonparametric estimation of nonincreasing and symmetric unimodal density functions with bounded supports we determine the projections of estimates onto the convex families of possible parent densities with respect to the weighted integrated squared error. We also describe the method of approximating the analogous projections onto the respective density classes satisfying some general moment conditions. The method of projections reduces the estimation errors for all possible values of observations of a given finite sample size in a uniformly optimal way and provides estimates sharing the properties of the parent densities.     

密集型克隆植物冬小麦对温度与养分的反应

为揭示密集型克隆植物在未来气候暖化下的反应格局,在控制实验条件下选用冬小麦接受两种温度和两种养分水平的处理。结果显示：温度对冬小麦的克隆生长、有性繁殖、生物量在各部分间的分配均产生了极显著的影响;而养分对多数性状的影响不显著;并且温度很少与养分发生交互效应。在全球暖化的背景下从克隆植物适应对策的角度对研究的结果进行了讨论。     

黄河流域的竹林分布与秦汉气候史的认识

秦汉时期黄河流域的竹林分布是生态史研究和经济史研究都应当关注的历史事实。认为当时黄河流域的竹林非“自然生”、“皆为经济栽培的产物”的意见缺乏论据。竹林分布的变化,实具有“气候变迁指示意义”。竺可桢在《中国近五千年来气候变迁的初步研究》一文中以“竹”的分布论述秦和西汉时期的“温和”气候,是有说服力的。     

Current Constraints and Future Directions for Risk Adapted Land-Use Planning Practices in the High-Density Asian Setting of Ho Chi Minh City

The need to integrate adaptation efforts into land-use planning policies has been only recently recognized in Ho Chi Minh City. The city's latest planning guidance addresses both flooding resilience and mitigation of urban heat. This paper outlines the development contexts and the current barriers for adapted land-use planning within the city. The key challenge for land-use planning is communicating the important functions and services of open and natural urban spaces and effectively guiding the mainly individual developer-driven development. As the realization of non-structural adaptation measures is in strong contrast to the current market-driven private and short-term developer interests, the main development trajectories are questioned and synergies identified.     

基于投影的fMRI时间序列图像配准方法研究

利用投影技术,针对功能磁共振时间序列图像,介绍了一种新的自动图像配准方法。该方法将序列图像二值化后沿着水平方向或垂直方向进行投影,根据投影向量元素的位置和大小,快速地计算出图像的旋转、平移运动的变化参数。仿真实验和实际的功能磁共振应用证实了该方法的有效性。     

力比多的压抑、投射与移置——《金锁记》人物悲剧心理因素解析

弗洛伊德认为,人的性本能即"力比多"是一切本能中最基本的内容,这也是我们解读《金锁记》人物心理因素的最佳注脚。力比多的压抑和投射的失败使七巧成为被害者,而力比多的移置又使她成为加害者。     

Penalized contrast estimator for adaptive density deconvolution

The authors consider the problem of estimating the density g of independent and identically distributed variables X_I, from a sample Z₁,… Z_n such that Z_I = X_I + σ? for i = 1,…, n, and E is noise independent of X, with σ? having a known distribution. They present a model selection procedure allowing one to construct an adaptive estimator of g and to find nonasymptotic risk bounds. The estimator achieves the minimax rate of convergence, in most cases where lower bounds are available. A simulation study gives an illustration of the good practical performance of the method.     

周代的生态观

周代非常重视保护自然资源,颁布了严厉的禁采禁捕法令,由各种专职官员负责实施。公元前780年三川流域发生大震灾,西周的自然生态和社会生态遭到毁灭性的破坏。太史伯阳父依据当时的生态危机和政治危机,参考夏、商灭亡的历史经验,预言了西周10年内必将灭亡。《礼记.月令》记述了周代一系列的禁采禁捕法令,以及气象异常与水、旱、风、疫等灾害的关联。这些关联,当是先民长期经验的总结,应予足够的重视,并值得学者深入研究,或可从中发现某些规律,作为现代短期灾害预测的参考。     

关于一集类圆柱投影的探讨

本文所要探讨的是一集类圆柱投影。它不同于伪圆柱投影,而属于标准线型投影族的一个新类型;其中包含着两个新型的等面积投影。     

Managers' attitudes about firm responsibilities

A mail survey was conducted in order to investigate whether the importance a manager attaches to corporate ethical and legal responsibilities varies according to personality characteristics, demographic variables, or the perceived moral climates in the manager's firm. Respondents were middle- and lower-level managers in 112 for-profit businesses located throughout the United States. As expected, attitudes about corporate ethical responsibility were significantly related to (1) the individual's capacity for empathy and (2) a perceived caring climate in the firm; attitudes about corporate legal responsibility were significantly related to (1) the individual's hierarchical position and (2) an organizational climate perceived to be supportive of law.Data collection for this research was subsidized by the Old Dominion University Research Foundation and the ODU College of Business and Public Administration Bureau of Research.