设置三角形阻流件的通道内流体流动特性研究

对常物性流体在通道内的周期性充分发展层流流动特性进行二维数值计算分析,所研究的通道是由两平行平板和交错布置于两平行平板上的多个三角形阻流件构成。给出了不同阻流件高度、顶角和间距以及不同Re 数下的流函数图和阻力特性曲线。     

美联储货币政策传导和操作特点评析

美联储的货币政策中介目标经过了由利率到货币供应量,再到隐含中介目标的变化,目前以联邦基金利率为操作目标;其货币政策主要通过联邦基金市场向国民经济各个部门传导.在泰勒规则的指导下,美联储的货币政策操作具有自主性、公开性、前瞻性、市场化和模型化的特点.美联储的货币政策操作经验,对我国亦具有现实的借鉴意义.     

The effect of differential accounting conservatism on the “over-valuation” of high-tech firms relative to low-tech firms

This paper examines systematic differences in the level of accounting conservatism between high-tech and low-tech firms. Relying on the recent development in theoretical models and empirical measures of conservatism, we investigate conservative accounting practices and earnings management behavior in high-tech and low-tech firms. The results based on comparisons of cumulative nonoperating accruals, regression coefficients from the income timeliness models in Basu (1997), the distribution of earnings, and discretionary accruals between the two groups are consistent with a higher level of accounting conservatism in high-tech firms vis-à-vis low-tech firms. Additional analyses show that the effect of conservatism cannot be used as a defense for the over-valuation of high-tech firms.     

货币危机频繁爆发的原因及对策——兼论我国金融体系改革

商业银行股份制改造已进入实质性阶段,以此为契机,中国金融体系改革也面临着前所未有的机遇与挑战。在经济、金融自由化的今天,我国将要面临的风险与外部冲击必然会增多。在此背景下重提货币危机,有着较为重大的理论与现实意义。     

关于企业集团合并申报纳税的思考

随着“两法合并”步伐的加快,有关企业集团合并申报纳税的相关问题,税企双方均应予以重点关注,本文拟从实践角度对这一问题加以探讨。合并申报纳税的发展状况近年来随着国际竞争的加剧,呈现出以所得税政策适应企业组织结构调整的趋势,其中一个重要特征就是打破了传统会计主体与     

Risk measurement distortion: an improved model of return smoothing

We examine the effects of smoothed hedge fund returns on standard deviation, skewness, and kurtosis of return and on correlation of returns using a MA(2)-GARCH(1,1)-skewed-t representation instead of the traditional MA(2) model employed in the literature. We present evidence that our proposed representation is more consistent with the behavior of hedge fund returns than the traditional MA(2) representation and that the traditional method tends to overstate the degree of smoothing observed in hedge fund returns. We examine methods for correcting the distortive effects of smoothing using our representation.     

Intelligent agents for adaptive security market surveillance

Market surveillance systems have increasingly gained in usage for monitoring trading activities in stock markets to maintain market integrity. Existing systems primarily focus on the numerical analysis of market activity data and generally ignore textual information. To fulfil the requirements of information-based surveillance, a multi-agent-based architecture that uses agent intercommunication and incremental learning mechanisms is proposed to provide a flexible and adaptive inspection process. A prototype system is implemented using the techniques of text mining and rule-based reasoning, among others. Based on experiments in the scalping surveillance scenario, the system can identify target information evidence up to 87.50% of the time and automatically identify 70.59% of cases depending on the constraints on the available information sources. The results of this study indicate that the proposed information surveillance system is effective. This study thus contributes to the market surveillance literature and has significant practical implications.     

高管过度自信、研发投入跳跃与企业绩效——来自中国上市公司的经验证据

基于间断平衡理论和高阶梯队理论，以2007-2017年中国沪深两市902家制造企业为样本，实证分析研发投入跳跃对企业绩效的影响以及高管过度自信的调节作用。结果显示：研发投入正向跳跃和负向跳跃均有助于提升企业绩效，高管过度自信正向调节研发投入跳跃与企业绩效间的关系。引入高管过度自信这一重要高管特征作为调节变量，有助于重新认识管理者心理偏差对企业创新行为和绩效的影响，较好地弥补了研发投入跳跃对企业绩效影响机制的研究空缺，丰富了创新间断平衡理论研究。研究表明，企业应重视高管心理特征的影响并结合自身实际情况，合理选择研发投入策略以改善企业绩效。     

REAL OPTIONS WITH COMPETITION AND REGIME SWITCHING

In this paper, we examine irreversible investment decisions in duopoly games with a variable economic climate. Integrating timing flexibility, competition, and changes in the economic environment in the form of a cash flow process with regime switching, the problem is formulated as a stopping‐time game under Stackelberg leader‐follower competition, in which both players determine their respective optimal market entry time. By extending the variational inequality approach, we solve for the free boundaries and obtain optimal investment strategies for each player. Despite the lack of regularity in the leader's obstacle and the cash flow regime uncertainty, the regime‐dependent optimal policies for both the leader and the follower are obtained. In addition, we perform comprehensive numerical experiments to demonstrate the properties of solutions and to gain insights into the implications of regime switching.     

围绕产业链部署创新链——论科技创新与产业创新的深度融合

当代国际竞争突出表现为全球价值链竞争。创新发展的关键是推动产业迈上全球价值链中高端。突破口就是围绕产业链部署创新链，把科技创新落到产业发展上。我国产业迈上全球价值链中高端主要有两个方向：一是建立以我国拥有的核心高端技术为主导的全球价值链，二是从全球价值链中低端环节向中高端环节攀升。这两个方向实际上指明了围绕产业链部署创新链的方向。在产业链上部署创新链，关键是在相应的产业链环节上创新处于国际前沿的核心技术。产业创新链的基本功能是有效衔接知识创新和技术创新两大体系。产学研协同创新更适合产业创新链的构建。