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991.
992.
i , i = 1, 2, ..., k be k independent exponential populations with different unknown location parameters θ i , i = 1, 2, ..., k and common known scale parameter σ. Let Y i denote the smallest observation based on a random sample of size n from the i-th population. Suppose a subset of the given k population is selected using the subset selection procedure according to which the population π i is selected iff Y i Y (1)d, where Y (1) is the largest of the Y i 's and d is some suitable constant. The estimation of the location parameters associated with the selected populations is considered for the squared error loss. It is observed that the natural estimator dominates the unbiased estimator. It is also shown that the natural estimator itself is inadmissible and a class of improved estimators that dominate the natural estimator is obtained. The improved estimators are consistent and their risks are shown to be O(kn −2). As a special case, we obtain the coresponding results for the estimation of θ(1), the parameter associated with Y (1). Received: January 6, 1998; revised version: July 11, 2000  相似文献   
993.
该文根据先进文化的特征 ,认为可持续发展是精神文明的本质体现 ,是精神文明创新 ;先进文化是可持续发展的灵魂 ,并论述了先进文化与可持续发展的辩证互动关系。同时提出精神文明建设新课题 ,一是要加强关于可持续发展的科学管理、综合决策和法制建设 ;二是要在全社会进行可持续发展价值观的教育 ,让人们牢牢地树立起“可持续发展”观念 ,以改变人们不良的生产方式和生活方式 ;三是要进一步反对利己主义、拜金主义和享乐主义 ,提倡适度消费 ,建立起既符合国情 ,又具有可持续性的生活方式  相似文献   
994.
森林认证的三大基础活动   总被引:5,自引:3,他引:2  
该文首次提出制定森林可持续经营的标准和指标、绿色消费运动、标准化及其认证是森林认证的三大基础活动。指出森林可持续经营标准和指标的实施及认证产品市场的形成是森林认证的内部动力和外在驱动 ,国际标准化及认证行动为森林认证的开展提供了丰富的经验。  相似文献   
995.
This paper explores the issues inherent in defining contracts for service delivery between the state and charitable organisations, and in differentiating them from grants. It begins by making the point that there is no one correct definition of a contract; rather, it is a function of its purpose. It then details our work in developing a definition of a contract within the national accounting tradition, as part of a study of the contribution of charitable organisations to the GDP of the United Kingdom. The paper ends by drawing some general conclusions from this experience.  相似文献   
996.
This study proves once again that too many press releases are poorly written and over-written, with long sentences and paragraphs, and poor syntax as well as weak and passive construction. In their use of press releases, journalists almost always have to make them simpler, shorter, easier to read, and less passive.The authors conclude that success in writing of press releases requires brevity and simplicity, shorter paragraphs, sentences, and words, and the elimination of the passive voice.Timothy Walters is an assistant professor of communication at Stephen F. Austin State University in Nacogdoches, TX. Lynne Walters is associate professor of journalism and Douglas Starr professor of journalism, both at Texas A&M University, College Station. Lynne Walters is currently a Fulbright professor at the American Journalism Center in Budapest, where her husband Timothy is also on a one-year appointment as a visiting professor.  相似文献   
997.
Couple and therapist perspectives about the use and process of reflecting team practice were analyzed using ethnographic research. A domain analysis was performed on postession interviews from both couples and therapists, and on field notes from each therapist. Seven couples and five therapists were interviewed at least twice over a 4-month period concerning their reactions to and perceptions of reflecting team practice. Six domains concerning reflecting team practice emerged from the analysis: (a)benefits of its use, (b) effects of gender, (c)recommended use, (d) contraindicated use, (e) the importance of creating spatial separateness between couple and team members, and (f) sequences of communication between the couple and team members that elicit change. The latter two domains described the process of reflecting team practice (i.e., steps in how it is used and how it is implemented). The role of ethnog rahy in reflecting team practice and in family therapy research is discussed.  相似文献   
998.
This paper introduces continuous‐time random processes whose spectral density is unbounded at some non‐zero frequencies. The discretized versions of these processes have asymptotic properties similar to those of discrete‐time Gegenbauer processes. The paper presents some properties of the covariance function and spectral density as well as a theory of statistical estimation of the mean and covariance function of such processes. Some directions for further generalizations of the results are indicated.  相似文献   
999.
Annual radiation doses and risks to the public living near, and traveling on, public highways, and occupational doses are calculated for highway shipments of radioactive materials under accident-free and incident-free conditions (i.e., under normal transportation conditions). The database developed by Sandia National Laboratories is used, and calculations are made using RADTRAN 4.0. This report is one of two reports estimating radiological risk associated with transportation of radioactive materials.  相似文献   
1000.
An exact conditional test is developed for testing the absence of an edge in a graphical covariance selection model and is shown to be equivalent to a test based on the partial correlation coefficient. An example is given.  相似文献   
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