团队科学创造力的提升需重视团队成就目标导向——被调节的中介效应

基于创造力成分等多维理论，构建以团队反馈寻求行为为中介变量，团队凝聚力为调节变量的被调节的中介效应模型，以期深入解释创新团队成就目标导向如何影响其团队科学创造力。基于129个理工科大学生科技创新团队数据，研究结果表明，团队学习目标导向和团队表现目标导向分别与团队科学创造力有显著的正向和负向关系；团队反馈寻求行为在团队成就目标导向与团队科学创造力间起部分中介作用；团队凝聚力负向调节团队反馈寻求行为与团队科学创造力间的关系，并弱化了团队成就目标导向通过团队反馈寻求行为对团队科学创造力的间接影响。结论对提高科技创新团队科学创造力有一定指导价值。     

基于网络的决策支持系统在水资源管理中的应用

综述了决策支持系统(DSS)与基于网络的决策支持系统(Web-based DSS)在水资源管理中的应用概况,通过对二者进行比较,指出Web-based DSS具有便于系统更新维护、降低用户使用门槛、扩展用户沟通渠道等优势。对Web-based DSS涉及的基础应用开发、多源信息采集与集成、多模块并行耦合、决策效果评估等关键技术进行了分析,探讨了Web-based DSS在多源异构大数据环境下面临的问题与挑战。     

国有风险资本与企业融资约束: 如愿以偿还是事与愿违?

我国国有风险资本是否实现了设立之初的目标,即是否纾解了企业融资困难呢?文章基于上市企业微观数据和手动采集的国有风险资本数据对此进行了系统研究.实证结果稳健地显示,国有风险资本可有效缓解企业后续融资约束,我国政府参与风险投资活动是有效的.进一步地,高持股比例、多联合投资、高政治层级的国有风险资本对受资助企业融资约束的缓解作用更强;且国有风险资本对经济欠发达、低制度质量环境下的企业、面临高环境不确定性和高竞争程度企业、民营企业、成长期与动荡期企业能产生更大的影响.机制检验表明,国有风险资本既能通过认证作用显著降低企业信息不对称程度,又能发挥政治关联的资源效应,包括显著促进银企关系和企业的商业信贷获取能力,并提升企业获得政府补贴的水平,从而减轻企业资金负担,缓解其融资约束.经济后果分析表明,国有风险资本能显著降低企业外部融资的股权资金成本和债务资金成本,帮助改善企业融资贵的难题,而且国有风险资本有助于企业在创新和经营方面的良性发展.但国有风险资本并未起到有效监督作用,不能缓解企业代理问题,尤其是会导致第一类代理成本的明显提高,而高管薪酬提升是其中的重要原因.据此,文章认为在未来的国有风险资本发展中,要把握"政府角色"介入的尺度,完善国有风险资本对企业的监督管理机制.同时适当兼顾各地区发展不平衡的情况,对中西部地区的国有风险资本发展提供适当且必要的帮助,以促进国有风险资本在新时期的长足发展.     

利用价值工程在棚户区项目拆迁地块选址决策的模型建立

本文以价值工程理论为基础,收集现有不同地块基础数据,利用多元线性回归方法确定备选方案棚户区改造项目的成本系数.通过分析影响拆迁地块选址决策影响因素,利用层次分析法确定各备选方案功能系数.对各备选方案的价值系数进行计算后,以价值系数为评价值确定最优拆迁地块.     

Who benefits from partial tax coordination?

In this paper, we investigate whether partial tax coordination is beneficial to countries within and outside a tax union, in which countries are supposed to compete in taxes and infrastructure. Our results demonstrate that a subgroup of countries agreeing on a common tax rate can harm both member and nonmember states. This is in contrast to the classical findings that partial tax harmonisation is Pareto improving. When a minimum tax rate is imposed within a tax union, we demonstrate that it does not necessarily improve the welfare of the member countries. Moreover, both the high‐tax and low‐tax countries can be worse off. This conclusion is at odds with the classical result that a high‐tax country benefits from the imposition of a lower tax bound.     

自动涂胶系统胶枪的热分析

为研究自动涂胶系统的胶枪最优材质、最佳热源位置和最佳测温位置,利用ANSYS Workbench软件对自粘胶胶枪进行数值模拟.通过分析不同材质胶枪的温度场分布情况,结合经济性和加热性能,选定最优胶枪基材.同时分析得出加热自粘胶至工作温度的时间和保持工作温度的加热功率,确定了热源和测温点位置,拟定了升温策略.进行自粘胶胶枪加热试验,验证了仿真分析结果的准确性.     

离心泵并联运行工况点的数值求解

建立了求解多台不同型号离心泵并联运行工况点的数学模型,给出了用数值计算中的“二分法”求解该模型的方法,并附有用Exce l计算的实例。     

Effects of surface charge, micro-bubble size and particle size on removal efficiency of electro-flotation.

Flotation is a water treatment alternative to sedimentation, and uses small bubbles to remove low-density particles from potable water and wastewater. The effect of zeta potential, bubble size and particle size on removal efficiency of the electro-flotation process was investigated because previous model-simulations indicated that these attributes are critical for high collision efficiency between micro-bubbles and particles. Solutions containing Al3+ as the metal ion were subjected to various conditions. The zeta potentials of bubbles and particles were similar under identical conditions, and their charges were influenced by metal ion concentration and pH. Maximum removal efficiency was 98 and 12% in the presence and absence of flocculation, respectively. Removal efficiency was higher when particle size was similar to bubble size. These results agree with modelling simulations and indicate that collision efficiency is greater when the zeta potential of one is negative and that of the other is positive and when their sizes are similar.     

Motivations and barriers of foreign R&D activities in China

The continued growth of the Chinese economy accompanied with the expansion of international investment in China has led to an increase in foreign research and development (R&D) activities in the country. Aside from the rising importance of R&D internationalization, research on foreign R&D in China has been neglected in the past due to its emerging status. In this article we examine drivers and barriers for conducting R&D in China. The focus of our research is on transnational companies typically characterized by decentralized R&D activities. Our research is mainly based on qualitative interviews with senior R&D managers. The success of foreign R&D activities in China strongly depends on the realistic estimation of its advantages and the proper identification and handling of barriers.