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对专家的咨询调查表明 :现代信息技术环境中的馆藏信息资源 ,最重要的是应当突出资源特色 ;收藏信息的载体形式 ,高校馆、公共馆、科学馆和社科情报所 ,应以印刷型和光盘型为主 ,科技情报所、信息中心、咨询和企业情报机构 ,应以网络型和光盘型为主 ;信息资源开发的重点是经济信息和科学技术信息 ;应重点开发的资源形式是网络信息和文献信息 ;应进行信息资源的多层次开发 ,开发方式主要是建设数据库、实现一次文献的数字化和计算机信息分析。表 8。参考文献 3。  相似文献   
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美声唱法分为“靠前”与“靠后”两大学派。“靠前唱法”强调声音的明亮、靠前、打在硬口盖上.集中于面孔前部(鼻腔、面罩)部位;“靠后唱法”则强调声音的厚度、力度、喉腔开度大,音的立体柱状感及音的落点感受较深。它们有机结和点在于声音的明亮集中、圆润、丰满,两派是互补的辩证统一的。  相似文献   
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Direct and indirect measures were used to compare the written language abilities of three groups of college students: two with learning disabilities and one without learning disabilities. Main effects were found for group, but not gender. Differences between nonlearning disabled students (NLD) and those with learning disabilities (LD) in writing were evident on both types of measures. Performance by LD students with disabilities in an area other than writing differed depending on the type of measure and often was no different from either of the other two groups. The combined use of direct and indirect measures appeared most effective for examining the complexities of writing produced by all groups.  相似文献   
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In this paper, we presented a novel method for the facile and efficient one-pot synthesis of 2-arylbenzoxazoles, which oxygen atmosphere with anhydrous tetrahydrofuran (THF) as solvent or in solvent-free condition. The results show that this method could bring excellent yields as high as 96%. THF was proven to be the best choice among several solvents screened and the reaction was tolerated with a variety of aromatic aldehydes possessing electron-donating or withdrawing groups. The advantages of the present method lie in catalytic process using economic and environmentally benign dioxygen as oxidant.  相似文献   
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根据平面闭合曲线切线象理论,定义了切线全旋转角的概念,提出并论证了一种用曲线的曲率关于切线全旋转角的函数和进行平面四连杆机构轨迹综合的新方法。这是一种可应用于工程设计的几何系统分析法。  相似文献   
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政府电子信息存储中心的构建研究   总被引:2,自引:0,他引:2  
政府电子信息储存中心是保留与储存政府重要电子信息,实现政府电子信息处理的全程监控、在线自动捕捉与索引、迁移与处置证明等服务的重要信息机构。本文主要探讨了这种信息机构构建的必要性、可实现的功能、构建过程中需要克服的障碍及搭建过程中设备、人员、资金等的选择与配置问题。  相似文献   
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PURPOSE: The purpose was to determine the impact of online journals on the citation patterns of medical faculty. This study looked at whether researchers were more likely to limit the resources they consulted and cited to those journals available online rather than those only in print. SETTING: Faculty publications from the college of medicine at a large urban university were examined for this study. The faculty publications from a regional medical college of the same university were also examined in the study. The number of online journals available for faculty, staff, and students at this institution has increased from an initial core of 15 online journals in 1998 to over 11,000 online journals in 2004. METHODOLOGY: Searches by author affiliation were performed in the Web of Science to find all articles written by faculty members in the college of medicine at the selected institution. Searches were conducted for the following years: 1993, 1996, 1999, and 2002. Cited references from each faculty-authored article were recorded, and the corresponding cited journals were coded into four categories based on their availability at the institution in this study: print only, print and online, online only, and not owned. Results were analyzed using SPSS. RESULTS: The number of journals cited per year continued to increase from 1993 to 2002. The results did not indicate that researchers were more likely to cite online journals or were less likely to cite journals only in print. At the regional location where the number of print-only journals was minimal, use of the print-only journals did decrease in 2002, although not significantly. CONCLUSION/DISCUSSION: It is possible that electronic access to information (i.e., online databases) has had a positive impact on the number of articles faculty will cite. Results of this study suggest, at this point, that faculty are still accessing the print-only collection, at least for research purposes, and are therefore not sacrificing quality for convenience.  相似文献   
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