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101.
赵月明 《杭州师范学院学报(社会科学版)》2002,(6):108-110
高校转入学分制后面临着许多问题,集中表现为教务管理信息激增和工作难度加大。为提高工作效率,必须利用计算机和网络技术,对与学分制相关的环节和要素进行整合,即构造教务综合管理体系。在构建该体系的指导思想、制度依据的基础上,提出构建步骤和体系框架,综合解决教务管理工作中的几个紧迫问题。 相似文献
102.
依据WTO组织、协议和基本原则;分析了“教育服务”纳入WTO贸易总协定的服务贸易范围及西欧一些国家利用“教育服务”的经济前景;探讨了我国高等教育进入国际“教育服务”市场后发展的途径. 相似文献
103.
B. Streit 《Cellular and molecular life sciences : CMLS》1992,48(10):955-970
The fate of environmental pollutants — the various isotopes of elements, and inorganic or organic compounds — is a fundamental aspect of ecology and ecotoxicology, and bioaccumulation is a phenomenon often discussed in this context. Human activities have drastically altered natural concentrations of many substances in the environment and added numerous new chemicals. An understanding of the processes of bioaccumulation is important for several reasons. 1) Bioaccumulation in organisms may enhance the persistence of industrial chemicals in the ecosystem as a whole, since they can be fixed in the tissues of organisms. 2) Stored chemicals are not exposed to direct physical, chemical, or biochemical degradation. 3) Stored chemicals can directly affect an individual's health. 4) Predators of those organisms that have bioaccumulated harmful substances may be endangered by food chain effects. While former theories on the processes of bioaccumulation focused on single aspects that affect the extent of accumulation (such as the trophic level within the food chain or the lipophilicity of the chemical), modern theories are based on compartmental kinetics and the integration of various environmental interactions. Concepts include results from quantitative structure-activity relationships (QSAR), pharmacokinetics, ecophysiology and general biology, molecular genetic aspects and selection, and finally the structure of communities and man-made alterations in them. 相似文献
104.
105.
闻国椿 《烟台大学学报(自然科学与工程版)》1992,(4)
本文讨论n维空间区域上二阶完全非线性椭圆型方程的非正则斜微商边值问题的可解性,在某些自然结构的条件下,我们先给出了上述边值问题解的先验估计式,进而用参数开拓法证明了此边值问题的可解性。 相似文献
106.
107.
Bovas Abraham 《Journal of forecasting》1993,12(5):449-458
The practice of modelling the components of a vector time series to arrive at a joint model for the vector is considered. It is shown that in some cases this is not unreasonable. A vector ARMA model is used to model the Canadian money and income data. We also use these data to discuss the issue of differencing a multiple time series. Finally, models based on first and second differences are compared using forecasts. 相似文献
108.
Stephen K. McNees 《Journal of forecasting》1982,1(1):37-48
This article stresses how little is known about the quality, particularly the relative quality, of macroeconometric models. Most economists make a strict distinction between the quality of a model per se and the accuracy of solutions based on that model. While this distinction is valid, it leaves unanswered how to compare the‘validity’of conditional models. The standard test, the accuracy of ex post simulations, is not definitive when models with differing degrees of exogeneity are compared. In addition, it is extremely difficult to estimate the relative quantitative importance of conceptual problems of models, such as parameter instability across‘policy regimes’ In light of the difficulty in comparisons of conditional macroeconometric models, many model-builders and users assume that the best models are those that have been used to make the most accurate forecasts are those made with the best models. Forecasting experience indicates that forecasters using macroeconometric models have produced more accurate macroeconomic forecasts than either naive or sophisticated unconditional statistical models. It also suggests that judgementally adjusted forecasts have been more accurate than model-based forecasts generated mechanically. The influence of econometrically-based forecasts is now so pervasive that it is difficult to find examples of‘purely judgemental’forecasts. 相似文献
109.
竞争力薄弱是后勤服务企业在成长过程中遇到的典型问题,产生这一问题的根源有主客观两个方面,提高后勤服务企业竞争力有许多有效途径。研究高职高专后勤服务企业的竞争力问题将有助于后勤社会化改革的推进和深化。 相似文献
110.
李盘荣 《无锡职业技术学院学报》2007,6(1):57-59
该文对高职计算机网络课程教学的教学目的、教材选用、教学内容的组织,教学过程的实施和注重实践操作技能及改革考核方式等方面提出了探索和实施方法,得到一定的实效。 相似文献