基于语义匹配的采购联盟伙伴搜索方法

采购联盟合作伙伴的选择是采购联盟成功的一个关键,而伙伴搜索是伙伴选择重要的第一步。本文将电子商务中采购联盟伙伴搜索问题转换为采购需求文本的语义匹配问题,介绍了一种基于领域本体和语义相似度的采购联盟伙伴搜索模型。该模型通过对采购需求文本概念向量的上位填充和语义相似度计算来量化采购需求的语义匹配程度。     

领域本体构建与可视化展示研究

文章根据软件企业领域知识的多学科背景和开放性特点,综合应用知识工程与叙词表方法指导领域本体开发,复用Enterprise本体与TOVE本体的领域知识和概念模型构建领域本体框架,面向开源信息抽取本体概念,并利用     

基于顾客需求管理先验知识本体的数据挖掘改进方法研究

以顾客价值需求及行为理论为顾客需求管理领域的先验性知识,提出一种基于领域先验知识本体的需求数据挖掘改进方法,包括建立顾客需求领域本体和任务本体、引入本体进行挖掘的数据空间组织、挖掘算法选择及约束条件设置,并以移动服务为背景,给出该方法的应用示例及对管理决策的支持。     

酚类化合物对蝌蚪急性毒性的定量构效关系研究

对21种酚类化合物进行DFT-B3LYP/6-311G**水平全优化计算,据所得量子化学参数建立酚类化合物对日本长腿蛙蝌蚪24h急性毒性(24h-LC50)的定量构效关系(QSAR)模型。对训练集样本经逐步多元回归分析(SMR)后,所建QSAR模型的相关系数R及去一法(LOO)交互检验复相关系数R2cv分别为0.967和0.882,用预测集样本进行了外部预测,所得外部预测样本复相关系数R2ext和外部预测集交互检验Qe2xt分别为0.988和0.960,表明所建立的QSAR方程具有较好的稳健性和预测能力。模型结果表明:ELUMO愈负,化合物毒性愈强;分子疏水性参数logP较大时具有较大的脂溶性,化合物的毒性较大;极性愈大,毒性愈小。应用域(AD)表征表明建立的模型可以应用于应用域内化合物的毒性预测,具有潜在应用价值。     

一种基于领域的语义搜索引擎模型SSEM

Internet已成为全球最丰富的数据源,数据类型繁杂且动态变化,如何从中快速准确地检索出用户所需要的信息是一个亟待解决的问题.传统的搜索引擎基于语法的方式进行搜索,缺乏语义信息,难以准确地表达用户的查询需求和被检索对象的文档语义,致使查准率和查全率较低且搜索范围有限.本文对现有的语义检索方法进行了研究,分析了其中存在的问题,在此基础上提出了一种基于领域的语义搜索引擎模型,结合语义Web技术,使用领域本体元数据模型对用户的查询进行语义化规范,依据领域本体模式抽取文档中的知识并RDF化,准确地表达了用户的查询语义和作为被查询对象的文档语义,可以大大提高检索的准确性和检索效率,详细地给出了模型的体系结构、基本功能和工作原理.     

国内数字化作品版权保护的研究态势——基于文献计量的科学知识图谱分析

通过文献计量分析方法对中国学术期刊网络出版总库1996年至2011年的数字化作品版权保护论文进行研究,分析了论文的年代分布、期刊分布、学科分布、基金分布、高影响力论文等,利用文献可视化工具画图探讨了我国数字化作品版权保护的研究热点,并得出该领域的研究前沿.     

略论近代以来的不缠足运动

女子缠足是延续几千年的封建陋俗,严重摧残了妇女的身体健康,约束了妇女行动。满族入主中原,清廷曾对缠足下过几次谕令,但收效不大。近代以来,由于受到西方文明的冲击和影响,人们的放足意识不断提高,民国成立后,政府用法律条文的形式废除了缠足这一陋俗。废除缠足不仅对妇女生活有重要意义,而且对国家和社会都产生了深远影响。     

论书籍装帧设计艺术的和谐之美

本文从书籍装帧设计的图文版面、材质感知、文化内涵等方面进行阐释分析,强调树立装帧设计整体美感的重要性。只有做到书籍的内容与形式及材质的融会贯通、相辅相成,才能全方位地体现书籍装帧设计艺术的和谐之美。     

Effect of high glucose levels on the calcification of vascular smooth muscle cells by inducing osteoblastic differentiation and intracellular calcium deposition via BMP-2/Cbfα-1 pathway

In this paper,we investigate the effect and the possible mechanism of high glucose levels on the calcification of human aortic smooth muscle cells (HASMCs).HASMCs were divided into four groups: normal glucose group (NG),osmolality control group (OC),high glucose group (HG,HASMCs culture medium containing 30 mmol/L glucose),and high glucose plus recombinant human Noggin protein (bone morphogenetic protein-2 (BMP-2) antagonist) group (HN).The mRNA levels and the protein expressions of BMP-2 and core binding factor alpha-1 (Cbfα-1) were measured by real-time quantitative polymerase chain reaction (PCR) and Western blot.After induced by 10 mmol/L β-glycerol phosphoric acid,cells were harvested for assessments of alkaline phosphatase (ALP) activities at Days 1,2,and 3,and intracellular calcium contents at Days 7 and 14,respectively.High glucose levels increased the mRNA levels and the protein expressions of BMP-2 and Cbfα-1 (P0.05).The expression of Cbfα-1 was partially blocked by Noggin protein (P0.05),while BMP-2 was not (P0.05).After being induced by β-glycerol phosphoric acid,high glucose levels increased the ALP activity [(48.63±1.03) vs.(41.42±2.28) U/mg protein,Day 3;P0.05] and the intracellular calcium content [(2.76±0.09) vs.(1.75±0.07) μmol/mg protein,Day 14;P0.05] in a time-dependent manner when compared with the NG group,while the ALP activity could not be blocked by Noggin protein [(48.63±1.03) vs.(47.37±0.97) U/mg protein,Day 3;P0.05].These results show that high glucose levels can evoke the calcification of HASMCs by inducing osteoblastic trans-differentiation and intracellular calcium deposition via the BMP-2/Cbfα-1 pathway,which can be partially blocked by Noggin protein.     

Numerical computations of the flow in a finite diverging channel

The flow in a finite diverging channel opening into a large space and resembling the experimental prototype of Putkaradze and Vorobieff （2006） was numerically investigated. The effects of the Reynolds number, initial condition, intersection angle, length of the wedge edges, and the outer boundary condition were examined. The numerical results showed that the flow in the wedge undergoes a change from symmetrical flow to unsymmetrical flow with a weak backflow, then a vortical （circulation） flow and finally an unsteady jet flow as the Reynolds number is increased for an intersection angle of 32° and a wedge edge of length 30 times the width of the inlet slit. For the unsteady flow, the jet attached to one side of the wedge constantly loses stability and rolls up into a mushroom-shaped vortex-pair near the outlet of the wedge. As the intersection angle is increased to 50°, a stable jet flow is observed as a new regime between the vortex and unsteady regimes. Both the intersection angle and the wedge length have negative effects on the stability of the flow, although the effect of the wedge length on the critical Reynolds number for the symmetry-breaking instability is not pronounced. The outer boundary condition was found not to affect the flow patterns inside the wedge significantly. At a certain Re regime above the onset of symmetry-breaking instability, the flows evolve into steady state very slowly except for the initial stage in the case of decreasing flow flux. Two different solutions can be observed within the normal observation time for the experiment, providing a possible explanation for the hysteresis phenomenon in the experiment.