信息检索中修饰语作用的研究

在海量信息中检索时,与用户查询相关的信息常常被漏掉,而与查询无关的信息———信息垃圾,却大量地出现在检索结果中。改进文本信息检索系统的质量,提高检索效能,已成为亟待解决的问题。本文针对能够影响检索效力的一个易被忽略的因素———修饰语,研究其在文本信息检索中的作用。为此,构建了修正的向量空间模型(Modified Vector Space Model,MVSM),并以英文文本进行试验,进而说明修饰语的作用。     

知识检索研究

从知识检索概念、知识检索基础、知识检索模型、知识检索呈现和知识检索系统几方面,对知识检索的有关理论与方法作了概要梳理和分析。认为知识本体作为领域知识的语义模型,其主要功能体现在知识组织和知识检索两方面;只有以领域知识本体的知识组织体系为基础,才能真正实现基于语义的知识检索。     

浅谈垃圾情报源

废弃物品也可成为获取情报的一个重要来源,使得垃圾泄密事件层出不穷。文章从垃圾情报源的定义入手,对垃圾情报源的类型、特点进行了深入分析,并提出了解决垃圾泄密的措施。     

以CRM为导向的数据仓库模式研究

文章从CRM数据仓库与其他数据仓库的区别出发,介绍了其功能、操作上的特别之处。在CRM数据仓库逻辑结构基础上详细介绍了信息存储模式和数据处理模式。     

信息有序的理论框架

本文从普遍存在的无序向有序发展变化的理论,探讨信息从无序向有序发展的规律及现在普遍应用的方法及工具。最后,总结并揭示了信息有序发展的理论框架图。     

信息化促进工业转型升级的技术效率及其影响因素——以江苏省为例

以江苏省为例,在实证测度其13个地市2003-2017年信息化发展和工业转型升级指数的基础上,利用完全非参数随机前沿模型对信息化促进工业转型升级的技术效率进行测度,并采用面板Tobit模型对效率影响因素进行检验.结果 显示:江苏省工业转型升级的信息化效率普遍较高,考察期内13个地市的效率均值均在0.93以上,且呈明显的...     

关于师范学院图书馆迎接高校本科教学工作水平评估的几点思考

图书馆作为教学、科研的重要服务部门,在普通高等学校本科教学工作水平评估中占有一定的权重。结合评估指标和工作实践,论述高校图书馆应抓住评估契机,积极争取外部资金,充分挖掘内部潜力,努力提高服务质量,促进图书馆的建设与发展。参考文献8。     

科技型孵化器绩效影响因素的模糊集组态分析——以广州为例

为更好优化资源配置,从而更好地促进科技型孵化器产生高绩效,以广州市25家科技型孵化器为研究样本,借助"技术-组织-环境"(TOE)理论框架模型,运用组态思维和fsQCA方法整合技术、组织、环境3个层面5个条件因素,探讨影响科技型孵化器绩效的多维组合因素和促进路径.研究发现:(1)科技型孵化器绩效受多方面因素的共同作用,...     

Simultaneous changes in seed size,oil content and protein content driven by selection of SWEET homologues during soybean domestication

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.     

Wearable skin-like optoelectronic systems with suppression of motion artifacts for cuff-less continuous blood pressure monitor

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.