基于动态调整模型的最优资本结构影响因素实证研究

本文引入调整成本这一概念,构建了资本结构的动态调整模型。并基于面板数据分析方法,采用我国上市公司的最新财务数据和宏观经济指标,对动态调整模型进行了实证分析。实证结果表明,我国上市公司的资本结构的确存在向最优值部分调整的现象,在动态调整过程中的交易成本较小,这使得我国上市公司的资本结构调整到最优资本结构的比例较高。     

产业集聚能力的识别框架与培育路径

从动态经济系统视角提出产业集聚能力的概念,结合集群生命周期各阶段的特点及影响要素的系统分类,提出产业集聚能力识别的"三重螺旋"模型,构建包括资源状况、硬指标、软指标和市场特征等四个维度的评价指标体系,并对沈阳、大连、鞍山高新技术产业群的集聚能力进行综合评价。应以政府政策引导、合作网络建设和重点企业培养为主线培养产业集聚能力。     

Dynamic R&D choice and the impact of the firm's financial strength

ABSTRACT

This article investigates how a firm's financial strength affects its dynamic decision to invest in R&D. We estimate a dynamic model of R&D choice using data for German firms in high-tech manufacturing industries. The model incorporates a measure of the firm's financial strength, derived from its credit rating, which is shown to lead to substantial differences in estimates of the costs and expected long-run benefits from R&D investment. Financially strong firms have a higher probability of generating innovations from their R&D investment, and the innovations have a larger impact on productivity and profits. Averaging across all firms, the long-run benefit of investing in R&D equals 6.6% of firm value. It ranges from 11.6% for firms in a strong financial position to 2.3% for firms in a weaker financial position.     

我国区域经济安全动态监测分析

本文在界定我国区域经济安全内涵的基础上，通过国家经济安全指标依经济区域分解法，对影响我国经济安全的重点区域进行了一次全面动态的监测评估，定量研究发现：（1）2005-2009年，我国经济安全处于中度到低度不安全状态，其中影响我国经济安全的外来风险的85%集中在东部沿海七大省（市），经济风险省域高度集中，不利于分解我国的经济不安全状态，但近5年有缓慢下降态势。（2）我国经济安全防范能力的42%来自于东部沿海七大省（市），呈现低度集中结构，但近3年有缓慢上升态势。（3）2005-2009年，七大省（市）对全国经济安全的总体影响度为68%，经济风险呈现中度集中，但近5年有逐渐下降态势。（4）广东省对全国经济安全的影响度最高（19%），江苏省第二（13%），上海市第三（11%），浙江省第四（8%），山东省第五（7%），北京市（5%）与辽宁省（5%）并列第六位。     

Location factors of FDI and the growing services economy1

Foreign direct investment (FDI) has increasingly shifted toward the service sector. This change in the industrial composition of FDI and the non‐tradable nature of services may have altered the importance of location factors for investment decisions. To capture potential changes in FDI determinants, a contrasting sectoral analysis is performed. Based on FDI stock data from eight new EU member states for the period 1998–2004, we implement a dynamic panel approach allowing the speed of adjustment to the equilibrium investment level to vary across sectors. Results support our assumption that investment into the service sector, which is characterized by low installation costs, adjusts much faster to its desired level than manufacturing FDI. Thus, government interventions to attract FDI are likely to boost the service sector immediately while having a slower impact on manufacturing FDI. Furthermore, as services are mostly non‐tradable, FDI into this sector is largely based on market‐seeking motives while FDI in the manufacturing sector is also driven by international price competitiveness measured by real unit labour costs.     

高层住宅含钢量新旧规范对比研究

随着房地产经济环境的变化,房地产开发商愈加重视结构的经济性和含钢量对造价的影响。2011版结构新规范的执行对结构的含钢量指标变化较大,直接影响结构经济性。本文根据新规范的实施,实例统计地震烈度6度区高层住宅含钢量的变化,统计建筑面积、钢筋级别、抗震等级在高层住宅中的影响情况,并且分析了含钢量的统计影响因素,以提供资料数据予房地产开发商造价控制以及结构工程师的结构优化。分析结果表明,新规范的执行使得含钢量和混凝土用量均增加5%以上,其影响不可忽视。     

产品垂直差异、产品内分工与南北贸易

存在产品垂直差异和产品内分工的贸易模型可以更为深刻地考察南北贸易的模式及影响因素。其中,生产技术仍然是决定生产分工格局的重要决定因素,当其他条件保持不变时,如果南方生产技术水平提高,其将扩大生产范围,在保持生产原有质量产品的情况下,向更高质量产品的生产领域进军。而北方发生技术进步时,其生产范围将缩小,抛弃低质量产品的生产,专攻高质量产品的生产。当两国分别在不同的生产阶段发生技术进步时,基本变化趋势是使本国发生技术进步的生产阶段趋向高质量产品的生产。     

Traffic density,congestion externalities,and urbanization in China

ABSTRACT

Although there is an abundant regional literature analyzing traffic congestion, only a few studies have explored extending such analysis with spatial effects. This study uses a dynamic spatial Durbin model and city-level panel data for the period 2003–14 to investigate the spatial spillover effects of traffic congestion on urbanization in China. The results show that there is an inverted ‘U’-shaped relationship between urbanization and traffic density in local and neighbouring cities, and congestion effects have appeared. In the short and long run, the spatial effects of traffic congestion have become an important force restricting the effective promotion of urbanization in China.     

论联合体投标的实际应用

随着联合体投标情况的不断增加,如何确定政府采购活动中联合体身份,如何确定联合体资格要求及资质级别等成为招标投标工作人员必须面对的问题。文章结合相关法规条款对联合体投标作了简要分析。     

汽车传动轴弯曲振动分析

商用车传动轴是商用车传动系统中的重要部件,因其振动频率低、刚度小,加上万向节附加力矩,使得传动轴的弯曲振动问题成为影响商用车振动和噪声的重要方面。本文对某商用车传动轴的弯曲振动问题进行了动力学仿真分析,对传动系统的隔振性能进行了分析,总结出中间支撑的刚度对整个转动系的隔振性能的影响规律,对于今后设计具有一定借鉴作用。