网络信息生态链协同进化方略

[目的/意义] 通过对网络信息生态链协同进化的目标选择、过程控制和保障措施的分析,形成较为完善的网络信息生态链协同进化方略,指导网络信息生态链进行协同进化。[方法/过程] 基于现有相关研究成果,运用信息生态理论、协同进化理论,采用逻辑分析方法,先探讨网络信息生态链协同进化目标的类型及选择策略,进而提出网络信息生态链协同进化的过程控制和保障措施。[结果/结论] 网络信息生态链的协同进化目标有技术升级主导型、规模扩大主导型、功能提升主导型3种,选择协同进化目标要综合考虑网络信息生态环境变化、网络信息生态链现有水平和演进能力等因素。在网络信息生态链协同进化过程中,要处理好速度与质量、渐变与突变、连续与间歇、继承与创新的关系。网络信息生态链协同进化的保障措施包括统一所有节点的思想认识、提升核心节点的调控能力、加强整链的协同创新管理等。     

在线商品评论信息形成影响因素研究

本文从用户相关、商家相关、商品相关和发布平台相关这4个构面出发,研究这4个构面的内在特性对在线商品评论信息的影响。在研究的过程中,把在线商品评论信息划分为内容、数量和形成速度3个维度,并将4个构面对应的3个维度进行全面、系统地探讨。最终,提出影响在线商品评论信息的因素理论模型,为后续相关的实证研究提供参考。     

政府研发补贴的激励效应存在门槛吗？——基于融资结构视角的实证研究

以2014-2018年沪深A股上市公司为研究样本,建立面板数据门槛效应模型,从融资结构视角分析政府研发补贴与企业研发投入的非线性关系.研究结果表明,政府研发补贴对企业研发投入具有激励效应,但该激励效应存在融资结构门槛,其中债权融资率和股权融资率的门槛值分别为40.08％和21.80％.只有当企业的债权融资率低于门槛值、股权融资率高于门槛值时,政府研发补贴才能有效提高企业研发投入.因此,我国政府制定研发补贴政策时应考虑融资结构门槛,优化研发补贴的资源配置效果.     

主成分分析法的农民合作组织运营风险评价

在农民合作组织运营风险研究过程中,常常需要用多个变量进行综合评价,如涉及自然风险、经济风险、技术风险、组织风险等的众多个指标。通过建立农民合作组织风险评价指标体系,选取了26个可量化指标,应用主成分分析,将26个评价指标简化为10个更具代表性的指标,在实际分析中具有更强的可操作性。     

基于ISM的用户档案信息获取内容影响因素研究

运用文献分析法和专家咨询法提炼出用户档案信息获取内容的影响因素,将用户档案信息获取内容视作一个复杂系统,借助解释结构模型方法构建用户档案信息获取内容影响因素的多级递阶有向图模型,分析用户档案信息获取内容影响因素之间的作用关系.对用户档案信息获取内容影响因素的层级关系的揭示,可以从整体上把握各因素对用户档案信息获取内容的影响机理和各因素之间的相互作用机制,社会环境因素及用户的年龄和阅历是深层因素也是根本因素,用户的个体因素和档案馆建筑环境配置作为中层因素对用户档案信息获取内容产生较为直接的影响,表层因素直接影响用户档案信息获取内容.     

Clinical Teacher Preparation: A Retrospective

In this article, we explore how teacher preparation programs have developed from the mid-1800s to present day, emphasizing changes in the clinical component. Drawing from the history of teacher education from the normal schools of the 19th century to present-day interest in clinically based preparation, we first review the migration of teacher preparation from normal schools into higher education. Next we discuss how accreditation has shaped programs. We then turn our attention to major initiatives in the 1980s that explicitly focused on linking school improvement with teacher education reform—partnerships that emphasized clinical aspects of teacher preparation. Finally, we discuss efforts to enhance clinical learning, highlighting instructional strategies and issues regarding design, settings, and outcomes for programs as they work to meet challenging new accreditation standards.     

Dynamics of vascular volume and hemodilution of lactated Ringer＇s solution in patients during induction of general and epidural anesthesia

Objective： To investigate the dynamics of vascular volume and the plasma dilution of lactated Ringer＇s solution in patients during the induction of general and epidural anesthesia. Methods： The hemodilution of i.v. infusion of 1000 ml of lactated Ringer＇s solution over 60 min was studied in patients undergoing general （n=31） and epidural （n= 22） anesthesia. Heart rate, arterial blood pressure and hemoglobin （Hb） concentration were measured every 5 rain during the study. Surgery was not started until the study period had been completed. Results： General anesthesia caused the greater decrease of mean arterial blood pressure （MAP） （mean 15% versus 9%; P〈0.01） and thereby followed by a more pronounced plasma dilution, blood volume expansion （VE） and blood volume expansion efficiency （VEE）. A strong linear correlation between hemodilution and the reduction in MAP （r=-0.50;P〈0.01） was found. At the end of infusion, patients undergoing general anesthesia retained 47% （SD 19%） of the infused fluid in the circulation, while epidural anesthesia retained 29% （SD 13%） （P〈0.001）. Correspondingly, a fewer urine output （mean 89 ml versus 156 ml; P〈0.05） and extravascular expansion （454 ml versus 551 ml; P〈0.05） were found during general anesthesia. Conclusion： We concluded that the induction of general anesthesia caused more hemodilution, volume expansion and volume expansion efficiency than epidural anesthesia, which was triggered only by the lower MAP.     

Science Letters： Structure relationship of nitrochlorobenzene catalytic degradation process in water over palladium-iron bimetallic catalyst

Two isomers ofnitrochlorobenzene （o- andp-NCB） were treated by a Pd/Fe catalyst in aqueous solutions through catalytic amination and dechlorination. Nitrochlorobenzenes are rapidly converted to form chloroanilines （CAN） first through an amination process, and then rapidly dechlorinated to become aniline （AN） and CI^-, without the involvement of any other intermediate reaction products. The amination and dechlorination reaction are believed to take place predominantly on the surface site of the Pd/Fe catalysts. The dechlorination rate of the reductive degradation of the two isomers of nitrochlorobenzene （o-, and p-NCB） in the presence of Pd/Fe as a catalyst was measured experimentally. In all cases, the reaction rate constants were found to increase with the decrease in the Gibbs free energy （correlation with the activation energy） of NCBs formation; the activation energy of each dechlorination reaction was measured to be 95.83 and 77.05 kJ/mol, respectively for o- and p-NCB. The results demonstrated that p-NCBs were reduced more easily than o-NCBs.     

基于低碳偏好下的制造商信息收集与质量披露策略

研究基于消费者低碳偏好下,供应链中制造商对于信息收集与质量披露策略选择的问题,建立考虑消费者低碳偏好时的制造商和零售商之间的博弈模型;通过对信息收集和质量披露策略不同选择下供应链决策结果的比较,分析制造商在不同策略选择下的收益差异,得出质量披露成本和消费者低碳偏好差异程度与制造商策略选择之间的变化规律。最后,通过算例分析对于研究结论进行说明和验证。     

Finding New Pairing Mechanism for Heavy Fermion Superconductivity

正In heavy fermion superconductors,the effective mass of normal state heavy electrons can reach hundreds of times that of a free electron.Accordingly,the characteristic Fermi energy is reduced to the order of meV.Thus,the discovery of heavy fermion superconductivity in CeCu2Si2 by German scientist Frank Steglich in 1979 had two major consequences.First,the transition temperature(0.6 K)reaches 5%of the Fermi energy,much higher