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81.
我国信息资源共享实践及理论研究进展   总被引:53,自引:0,他引:53  
马费成  裴雷 《情报学报》2005,24(3):277-285
本文通过回顾信息资源共享的历史发展,研究信息资源共享的实践和理论进展,提出了信息资源共享的关键和目前存在的问题  相似文献   
82.
文章探讨了业务流程再造在图书馆管理中的重要意义,提出组织结构应采用以流程为导向的新型模式,并在此基础上制定了提高图书馆管理绩效的业务流程再造的原则和策略。  相似文献   
83.
李国昌  马严  陈琪 《出版科学》2018,26(3):28-31
将党中央提出的新发展理念合理地运用到编辑职业发展中,提出协调、融合、开放、卓越、共享的编辑新发展观,并对其内涵、主要特征和涵育路径进行论述.认为编辑新发展观是一个系统化的逻辑体系,具有人本性、参与性、创造性的鲜明特点.涵育编辑新发展观,需要国家加强顶层设计,厚植编辑茁壮成长的发展基础;需要单位坚持"以人为本",营造编辑干事创业风清气正的微环境;需要个人坚定文化自信,在出版业发展中不断超越自己.  相似文献   
84.
Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents.  相似文献   
85.
Libraries have been the key to preserving culture and historic legacy for centuries. One such treasure cataloged in The Pennsylvania State University (Penn State) Libraries is a collection of over 33,000 Sanborn? Fire Insurance Maps. Originally kept safe in metal drawers, the library has embarked on a journey to digitize this abundance of information, combine it with other media such as photographs, and make it accessible through a web interface. Inspired by these efforts, we accessed this information and took it to the next level. Using state of the art 3D modeling and immersive technologies, we created a historic 3D model and immersive experiences of Penn State, exemplarily for the 1922 campus. The resulting experiences can be accessed through the web but also through head mounted displays (HMDs) and mobile phones in combination with VR viewers such as the Google Cardboard. Additionally, they can be used anywhere in the world or on the campus itself as a way to enable remote and in situ experiences and learning. Immersive experiences let us connect to the past, the present and the future, and as such offer value to digital cultural heritage efforts.  相似文献   
86.
本文从目前水处理方向毕业设计存在的问题入手,提出了关于该专业水处理方向本科毕业设计中应该注意的几点问题及应该提高和加强的地方.  相似文献   
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Soybean accounts for more than half of the global production of oilseed and more than a quarter of the protein used globally for human food and animal feed. Soybean domestication involved parallel increases in seed size and oil content, and a concomitant decrease in protein content. However, science has not yet discovered whether these effects were due to selective pressure on a single gene or multiple genes. Here, re-sequencing data from >800 genotypes revealed a strong selection during soybean domestication on GmSWEET10a. The selection of GmSWEET10a conferred simultaneous increases in soybean-seed size and oil content as well as a reduction in the protein content. The result was validated using both near-isogenic lines carrying substitution of haplotype chromosomal segments and transgenic soybeans. Moreover, GmSWEET10b was found to be functionally redundant with its homologue GmSWEET10a and to be undergoing selection in current breeding, leading the the elite allele GmSWEET10b, a potential target for present-day soybean breeding. Both GmSWEET10a and GmSWEET10b were shown to transport sucrose and hexose, contributing to sugar allocation from seed coat to embryo, which consequently determines oil and protein contents and seed size in soybean. We conclude that past selection of optimal GmSWEET10a alleles drove the initial domestication of multiple soybean-seed traits and that targeted selection of the elite allele GmSWEET10b may further improve the yield and seed quality of modern soybean cultivars.  相似文献   
90.
According to the statistics of the World Health Organization, an estimated 17.9 million people die from cardiovascular diseases each year, representing 31% of all global deaths. Continuous non-invasive arterial pressure (CNAP) is essential for the management of cardiovascular diseases. However, it is difficult to achieve long-term CNAP monitoring with the daily use of current devices due to irritation of the skin as well as the lack of motion artifacts suppression. Here, we report a high-performance skin-like optoelectronic system integrated with ultra-thin flexible circuits to monitor CNAP. We introduce a theoretical model via the virtual work principle for predicting the precise blood pressure and suppressing motion artifacts, and propose optical difference in the frequency domain for stable optical measurements in terms of skin-like devices. We compare the results with the blood pressure acquired by invasive (intra-arterial) blood pressure monitoring for >1500 min in total on 44 subjects in an intensive care unit. The maximum absolute errors of diastolic and systolic blood pressure were ±7/±10 mm Hg, respectively, in immobilized, and ±10/±14 mm Hg, respectively, in walking scenarios. These strategies provide advanced blood pressure monitoring techniques, which would directly address an unmet clinical need or daily use for a highly vulnerable population.  相似文献   
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