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931.
王泽福 《北京林业大学学报(社会科学版)》2004,(Z1)
建设国际知名、国内高水平多科性研究型大学已成为北京林业大学的办学指导思想和奋斗目标 ,因此 ,图书馆面临着服务对象、服务内容、服务方式、服务针对性、服务层次等 5个方面的职能转换。针对形势变化和学校建设的需求 ,该文提出了图书馆在 4个方面的建设对策 :①建设研究型特色图书馆 ;②建设能提供深层次、全方位的文献信息导航服务的导航体系 ;③对文献信息资源进行重组和优化配置 ,建设特色馆藏 ;④启动支撑学科建设尤其是重点学科建设的“数字图书馆工程项目”。 相似文献
932.
孟莉 《北京林业大学学报(社会科学版)》2004,(Z1)
知识经济的核心是知识创新 ,而知识创新要求高等教育必须培养造就一批高素质的创新人才。数字化图书馆是高校图书馆发展的必然趋势。建设数字化图书馆对培养造就高素质的创新人才具有不可替代的重要作用。该文论述了数字化图书馆的概念、特征及其对培养高素质创新人才的重要作用 ,并提出了面向培养创新人才的数字化图书馆的建设方略 相似文献
933.
A constrained optimisation theory or choice in concurrent schedules of reinforcement is presented. The theory posits that subjects evaluate both reinforcement rates and the work rates required to produce them and select the most highly valued combination. The chosen reinforcement rate is obtained by efficiently allocating work rate across schedules. The theory provides a unified explanation for maximisation of the overall reinforcement rate, the law of least effort, choice under Conc FR FR, Conc VR VR. Conc VI VI and Conc VI VR schedules, and choice of work rate. 相似文献
934.
A mixture model with Laplace and normal components is fitted to wind shear data available in grouped form. A set of equations is presented for iteratively estimating the parameters of the model using an application of the EM algorithm. Twenty-four sets of data are examined with this technique, and the model is found to give a good fit to the data. Some hypotheses about the parameters in the model are discussed in light of the estimates obtained. 相似文献
935.
Joseph P. Romano 《Revue canadienne de statistique》1989,17(1):75-80
An important statistical problem is to construct a confidence set for some functional T(P) of some unknown probability distribution P. Typically, this involves approximating the sampling distribution Jn(P) of some pivot based on a sample of size n from P. A bootstrap procedure is to estimate Jn(P) by Jn(&Pcirc;n), where P?n is the empirical measure based on a sample of size n from P. Typically, one has that Jn(P) and Jn(P?n) are close in an appropriate sense. Two questions are addressed in this note. Are Jn(P) and Jn(P?n) uniformly close as P varies as well? If so, do confidence statements about T(P) possess a corresponding uniformity property? In the case T(P) = P, the answer to the first questions is yes; the answer to the second is no. However, bootstrap confidence statements about T(P) can be made uniform over a restricted, though large, class of P. Similar results apply to other functional T(P). 相似文献
936.
937.
Some of the possible determinants of changes observed in welfare caseloads are analysed in this study. The paper attempts
to explain variations in welfare caseloads on the basis of four different factors: macroeconomic conditions, interactions
with other income maintenance programmes, changes in the programme's parameters and changes in the demographic structure.
Different models are tested by applying time series techniques. The data employed are of an administrative nature and cover
the whole period that the Madrid programme has been in operation. The results show that the effects of both unemployment and
institutional variables are strong and significant. Macroeconomic effects on caseloads could be offset or reinforced by changes
in unemployment protection and reforms of the programme's parameters. The significant effects found for the share of lone-parent
applicants also show that demographic shifts could shape the trends of welfare rolls regardless of the changes in unemployment
or the implementation of institutional reforms.
The authors would like to thank Juan Gabriel Rodríguez, Minoru Kunizaki, Miguel Angel Malo and three anonymous referees for
their comments and suggestions. Financial and technical support from the Spanish Institute for Fiscal Studies, the Inter-ministerial
Commission on Science and Technology (SEC 2001-0746) and the Social Services Department of the Madrid Government is also gratefully
acknowledged.
Responsible editor: Christian Dustmann. 相似文献
938.
939.
This paper presents a review of the literature on the meaning, etiology and categorization of acting out symtomatology in children. It is apparent that there is no one cause nor is there one well defined disorder.DSM-III categories as they relate to behavior disorders are discussed and the problems of diagnosis are addressed. Appropriate treatment goals and interventions cannot be developed unless more global aspects of a child's functioning and the environment in which he lives are assessed. 相似文献
940.