基于马尔可夫模型的高校图书馆学科评价服务研究

随着"双一流"建设总体方案的提出，科研成果越来越受到重视，高校图书馆开展学科评价服务，对于提升图书馆的服务和地位具有至关重要的意义。本文在分析了吉林大学2010-2016年发表的论文总体情况的基础上，选取论文发表总量前10名的学科为研究对象，运用文献计量学方法和马尔可夫模型分析方法，与传统的评价指标相结合，构建相应的综合评价指标，消除学科间的基础差异，分析得出各个学科的发展速度和发展趋势情况。     

缩短刊期的实践与效果分析

通过对《西北植物学报》变更月刊前后两年期刊的影响因子和作者群分析，结果表明：2003年《西北植物学报》变更月刊的影响因子由2002年双月刊的0．390上升到0．607，总被引频次由476提高到824；2003—2004年发表基金项目论文总数占发表论文总数的平均比例由82．25％增加到87．83％，其中国家自然科学基金、国家“973”项目、国家“863”项目、国家“九五”、“十五”项目、中国科学院创新项目等合计平均总数由2001—2002年的331项增加到846项，由占当年发表各类基金项目资助发表论文总数的64．43％增加到67．78％；发表论文第一作者为博士的人数（含在读博士生）平均占当年发表论文总数的比例由40．67％上升到45．94％，院士作者也有所增加。变更月刊两年的实践体会是：在缩短刊期之前，要分析期刊所在学科的发展趋势和期刊在全国同类期刊中所处的发展位置，在论证的基础上实施变更，不宜跟风；期刊缩短刊期以后，要进一步加强编辑出版过程的质量管理，建设网络环境下的信息管理系统，以提高编辑出版工作效率。     

煤矿地下开采项目环境影响评价中的几个重点

本文根据龙岩市煤矿地下开采项目环境影响评价工作的实际经验,结合一般煤矿开采项目环境影响评价要点,就煤矿环评工作中的工程共同特点、主要环境影响评价因子、产业政策与行业规划、清洁生产分析、污染防治和生态保护措施、固体废物综合利用等几个重点内容,阐述在环评实践过程的几点体会.     

员工离职倾向影响因素的多变量分析

本文在问卷调查的基础上，采用因子分析法，提取出测度员工工作态度的四个主要因子。然后，采用多元相关分析法，探讨这四个因子与员工离职倾向的相关关系，找出引起员工离职倾向的关键因素。以此为基础，本文运用单因素方差分析法和交叉分析法，比较了西安地区国有企业、民营企业和三资企业中员工的离职倾向及其关键影响因素状况。     

变老是为了抗癌？

众所周知，我们人体是由活细胞组成的。这些活细胞不像木材或金属那样容易腐烂，而是能自我成长和补充。既然我们身体的各部分可以更新，为什么我们不能“长生不老”呢？ 最近美国得克萨斯州一位名叫多勒沃的生物学家偶然发现：我们变老是为了活得更久，变老是抑制癌症的必然代价。 生物体内一个迫使将要癌变的细胞“自杀”的细胞因子，是加快身体各组织老化的罪魁祸首。这一细胞因子是人体抵御癌症的第一道防线，是细胞活动的坚定卫士。哪怕只有一点点轻微异常，特别是对细胞 DNA的损伤，这个因子将会迫使细胞要么停止生长要么…     

SCI——一种全新的文献评价标准

介绍SCI出版和收录的最新动态，帮助读者全面了解SCI收录情况和标准，以及在收录刊物上发表的论文（称为“SCI论文”）时应该注意的问题。     

《今传媒》杂志学术月刊在海内外网络传播基本情况简讯

《今传媒》杂志2003年被国家新闻出版署批准为人文社科类学术月刊,在国内外公开发行,至今已走过了27个年头。2019年,《今传媒》杂志全年共刊发国家级课题论文11篇,省部级课题论文61篇,市级课题论文10篇,院校级课题论文53篇,课题总篇数占全年刊发论文篇数的21.6%。中国学术期刊影响因子年报(人文社会科学·2019版)对《今传媒》2019年期刊影响因子作了科学细化的统计分析,得出结论是:《今传媒》2019年期刊复合影响因子较上一年有明显的提升。     

Novel distribution pattern of fibrinolytic components in rabbit tissues extract： a preliminary study

Objective: The purpose of this work was to investigate the distribution pattern of fibrinolytic factors and their inhibitors in rabbit tissues. Methods: The components of the fibrinolytic system in extracts from a variety of rabbit tissues, including tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), plasminogen (Plg), plasmin (Pl) and α2 plasmin inhibitor (α2PI), were determined by colorimetric assay. Results: The tissue extracts in renal, small intestine, lung, brain and spleen demonstrated strong fibrinolytic function, in which high activity of tPA, Plg and Pl was manifested; whereas in skeletal muscle, tongue and stomach, higher activity of PAI-1 and α2PI showed obviously. Also excellent linear correlations were found between levels of tPA and PAI-1, Pl and α2PI, Plg and Pl. In related tissues, renal cortex and renal marrow showed distinctly higher activity of tPA and lower activity of PAI-1, with the levels of Plg and Pl in renal cortex being higher than those in renal marrow, where the α2PI level was higher than that in renal cortex. Similarly, the levels of tPA, Plg and Pl in small intestine were higher than those in large intestine, but with respect to PAI-1 and α2PI, the matter was reverse. In addition, the fibrinolytic activity in muscle tissue was lower, however, the levels of tPA, Plg, and Pl in cardiac muscle were obviously higher than those in skeletal muscles, and the levels of PAI-1 and α2PI were significantly lower than those in skeletal muscle. Conclusion: Our data demonstrate that a remarkable difference of the fibrinolytic patterns exists in rabbit tissues, which has probable profound significance in understanding the relationship between the function of haemostasis or thrombosis and the physiologic function in tissues.     

Resistance partial factor and reliability of cast ball-and-socket support joint

Considering the uncertainty of material performance, geometric characteristic and analysis method, the analysis of statistical parameters of the resistance of cast ball-and-socket support joints and the reliability analysis are carried out by JC method (improved first-order second-moment method) based on the relevant experimental data. Results show that the resistance partial factor of the joint increases with the increase of the reliability index. The resistance partial factors are suggested corresponding to the reliability index under different load combinations. Moreover, the suggested resistance partial factor is adopted in reliability design, and it is found that the reliability index of the joint is larger than the target reliability index. The optimal load combination is the one in which live load plays an important control role. Finally, based on the suggested resistance partial factors, the reliability analysis of cast ball-and-socket support joints of a project is conducted.     

半实物仿真的炉温智能控制系统设计

结合模糊控制与OPC技术,将电炉实物接入仿真计算机.利用Matlab建立一个二维模糊控制器,温差和炉温变化率为输入量,变压器电压为输出量;根据实际经验分析电炉的加热过程,制定控制规则表,写入控制规则,完成控制器;在Simulink中设计并完成半实物仿真控制图,即设计一个智能控制炉内温度的系统.对不同量化因子k1和k2、比例因子k3进行仿真,比较电炉温度曲线图,分析出较合理的因子参数,实现了对电炉炉温的有效控制.系统可节省大量的调试时间,又能获得较准确的仿真效果.