并联式TBCC发动机排气系统性能数值模拟

针对一个并联式涡轮基组合循环(Turbine Based Combined Cycle, TBCC)发动机排气系统的气动方案,对其在整个飞行包线范围内典型工作点上的流场进行了数值模拟研究,获得了飞行包线范围内排气系统相应的推力系数、升力、俯仰力矩随飞行马赫数的变化关系。计算结果显示,在整个飞行包线范围内,排气系统的轴向推力系数随着飞行马赫数先减小后增大,在跨声速飞行时降到最低 Ma=0.9,涡喷不加力时为0.562,加力时0.662),在设计点附近达到最大;升力和俯仰力矩性能在亚声速及跨声速飞行时较差,在超声速飞行时随着飞行马赫数增加逐渐好转。表明排气系统在跨声速飞行范围内工作时应采取措施以改善其性能。      

用基尼系数衡量我国收入公平的局限性探讨

文章认为,基尼系数在衡量我国收入公平问题存在的局限集中表现在基尼系数自身存在、衡量收入公平和我国收入差距特殊性三个方面。基于此,要结合对居民主观性评判起影响作用的因素和科学的理性统计数据两方面对我国收入公平问题做出符合实际的科学判断。     

Regional capital mobility in China: Economic reform with limited financial integration

This paper assesses the changes in the regional capital mobility in China during the period of economic reform in 1978–2008 by employing a panel time varying coefficient (TVP) model. This approach is much more suitable to model China's evolution in the regional capital mobility than a standard structural break model as China's reforms took place gradually and were often implemented over several stages. Using the TVP model, we find that (1) China's provincial capital mobility demonstrated a moderate improvement over the sample period, but worsened temporarily between 1994 and 1997. This is probably due to the government's effort to combat inflation which reduced the investment and transfers to regions; (2) regions with the most developed and least developed provinces experienced higher degree of capital mobility improvement than those in the middle.     

我国中小企业财务实力评价研究

借助于可量化的财务指标评价中小企业财务实力状况,这是中小企业经济发展评价研究的主要内容之一。本文从企业偿债能力、盈利能力、资产管理能力、现金流能力等维度设计11个财务指标,以改进的功效系数法对指标值进行综合评价,以主成分分析法对各项指标赋予权重,从而得出我国目前中小企业财务实力状况评价结果,并在此基础上提出相应的改进对策。     

The correlation coefficient and problems of inference in recreation research

Correlation analysis frequently has been used for the investigation of leisure research questions. This paper illustrates the problem of “unequal weighting of cases” which is present in the use of correlation analysis. It further illustrates how this problem can mislead researchers when they make substantive inferences about leisure.     

城市旅游经营效率评价模型研究

目前中国的城市旅游发展存在一种盲目扩张的现象，部分城市想通过扩大旅游业的投入（如大量兴建五星级酒店）来获取更多的旅游产出（收入），衡量一个城市旅游投入与旅游产出的比例关系是否合理是值得深入探讨的一个问题。因此本文构建了基于DEA方法的城市旅游投入产出效率即城市旅游经营效率进行评价模型，在模型中引入了修正系数的概念，以对不同区域的城市由于发展环境的不同造成的旅游产出的误差进行修正。最后对评价模型的适用进行了总结，并对未来的研究进行了展望。     

恩格尔定律:理论与检验

恩格尔系数作为衡量居民生活水平的重要指标,其理论基础是恩格尔定律。作为实证性定律,恩格尔定律并没有严格的理论推理,其在我国的应用也受到一些质疑。本文基于效用函数假设和马斯洛层次需求理论,对恩格尔定律进行了理论推导;并利用省际面板数据(1981～2010)对模型进行了检验,结果表明恩格尔定律在我国是成立的。因此,使用恩格尔系数评价和比较我国居民生活水平是可靠的。     

Analysis on Balance Gap between Saving and Credit Account in China

In China, the balance gap of credit and saving account emerged in 1995, and its amount enlarged since then. By the end of Dec. 2005, with 28.7 trillion RMB saving balance and 19.5 trillion RMB gross credit account balance, the gap between saving and credit account was as large as 9.2 trillion RMB, which indicated a 67.8% of credit/saving ratio. Some believed this phenomenon was resulted from on one hand, the rapid growth of saving account; and on the other hand, relatively slower expanding of credit account. Some believed cooling down cash demand was behind the gap, while others claimed the balance gap caused dead capital and inefficiency service of saving account. In fact, the balance gap between credit and saving account might not necessarily relate to dead bank capital. And the phenomenon itself could not indicate the down-tendency of finance power that underlay economy. Nevertheless, it was liquidity not the balance gap should be regarded an index of capital situation in financial organizations. Therefore the balance gap between saving account and credit account could not be viewed as criteria against liquidity position. Solution of this problem should lay in boosting financial innovation among commercial banks, expending capital market and encouraging or permitting commercial banks as well as state-owed funds to enter share market and so on.     

幂级数的除法

本文从复变函数展开为幂级数的待定系数法出发,提出了幂级数的除法的概念,并给出了幂级数的除法的运作方式,从而有效地解决了待定系数法比较繁杂这一困难,同时保证了运算结果的准确性。     

Qualitative Input–Output Analysis of the Indian Economic Structure

Qualitative input–output (IO) analysis can be considered mostly in terms of a graph-theoretic formulation, which involves the construction and use of an adjacency matrix, derived from a binary transformation of the IO coefficient matrix. Classical attempts at qualitative IO analysis have derived the structure from the direct IO coefficient table. In more recent attempts, greater sophistication has been achieved by incorporating a degree of quantification into the qualitative analysis. Also, the concept of important coefficients (IC) has been used for the construction of the adjacency matrix. The present study is carried out along these lines for the Indian economy.