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61.
多道程序设计中,进程之间出现同步问题可通过信号灯的不同设置来解决,即用P信号灯和V信号灯的对应关系来检测其正确与否。  相似文献   
62.
根据工程力学课程的特点,从力学的基本概念、教学方法和教学模式上对工程力学的教学体系进行了分析,以充分调动学生的学习积极性,进一步提高学生的逻辑思维能力和综合解决问题能力,增强学生的创新意识和创新能力。  相似文献   
63.
倪云虎  曹凌枫 《特区经济》2005,(12):227-229
2004年5月,中小企业板在深交所获准设立,一时间,围绕中小企业板对创业投资运作影响的讨论空前热烈。笔者认为,要研究中小企业板对创业投资的影响,就必须从创业板和创业投资的内在机理出发,来研究中小企业板的制度安排是否能保证二者形成良性互动,关键的就是要研究中小企业板在制度上离一个成熟的创业板有多远。目前,学者和业内人士普遍对中小企业板的作用不甚乐观,而近一年来的实践也似乎验证了这一观点,因此,加强中小企业板的制度建设,使之尽快过渡为创业板,已经成了管理者的当务之急。  相似文献   
64.
The margin system is the first line of defense against the default risk of a clearinghouse. From the perspectives of a clearinghouse, the utmost concern is to have a prudential system to control the default exposure. Once the level of prudentiality is set, the next concern will be the opportunity cost of the investors, because high opportunity cost discourages people from hedging futures, and thus defeats the function of a futures market. In this article, we first develop different measures of prudentiality and opportunity cost. We then formulate a statistical framework to evaluate different margin‐setting methodologies, all of which strike a balance between prudentiality and opportunity cost. Three margin‐setting methodologies, namely, (1) using simple moving averages; (2) using exponentially weighted moving averages; (3) using a GARCH approach, are applied to the Hang Seng Index futures. Keeping the same prudentiality level, it is shown that the one using a GARCH approach by and large gives the lowest average overcharge. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:117–145, 2004  相似文献   
65.
This article uses a nonparametric test based on the arc‐sine law (see, e.g., Feller, 1965 ), which involves comparing the theoretical distribution implied by an intraday random walk with the empirical frequency distribution of the daily high/low times, in order to address the question of whether the abandonment of pit trading has been associated with greater market efficiency. If market inefficiencies result from flaws in the market microstructure of pit trading, they ought to have been eliminated by the introduction of screen trading. If, on the other hand, the inefficiencies are a reflection of investor psychology, they are likely to have survived, unaffected by the changeover. We focus here on four cases. Both the FTSE‐100 and CAC‐40 index futures contracts were originally traded by open outcry and have moved over to electronic trading in recent years, so that we are able to compare pricing behavior before and after the changeover. The equivalent contracts in Germany and Korea, on the other hand, have been traded electronically ever since their inception. Our results overwhelmingly reject the random‐walk hypothesis both for open‐outcry and electronic‐trading data sets, suggesting there has been no increase in efficiency as a result of the introduction of screen trading. One possible explanation consistent with our results would be that the index futures market is characterized by intraday overreaction. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:337–357, 2004  相似文献   
66.
This article analyzes the effects of the length of hedging horizon on the optimal hedge ratio and hedging effectiveness using 9 different hedging horizons and 25 different commodities. We discuss the concept of short‐ and long‐run hedge ratios and propose a technique to simultaneously estimate them. The empirical results indicate that the short‐run hedge ratios are significantly less than 1 and increase with the length of hedging horizon. We also find that hedging effectiveness increases with the length of hedging horizon. However, the long‐run hedge ratio is found to be close to the naïve hedge ratio of unity. This implies that, if the hedging horizon is long, then the naïve hedge ratio is close to the optimum hedge ratio. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:359–386, 2004  相似文献   
67.
QUADRATIC TERM STRUCTURE MODELS FOR RISK-FREE AND DEFAULTABLE RATES   总被引:4,自引:0,他引:4  
In this paper, quadratic term structure models (QTSMs) are analyzed and characterized in a general Markovian setting. The primary motivation for this work is to find a useful extension of the traditional QTSM, which is based on an Ornstein–Uhlenbeck (OU) state process, while maintaining the analytical tractability of the model. To accomplish this, the class of quadratic processes, consisting of those Markov state processes that yield QTSM, is introduced. The main result states that OU processes are the only conservative quadratic processes. In general, however, a quadratic potential can be added to allow QTSMs to model default risk. It is further shown that the exponent functions that are inherent in the definition of the quadratic property can be determined by a system of Riccati equations with a unique admissible parameter set. The implications of these results for modeling the term structure of risk-free and defaultable rates are discussed.  相似文献   
68.
We apply a discrete choice approach to model the empirical behaviour of the Federal Reserve in changing the federal funds target rate, the benchmark of short‐term market interest rates in the US. Our methods allow the explanatory variables to be nonstationary as well as stationary. This feature is particularly useful in the present application as many economic fundamentals that are monitored by the Fed and are believed to affect decisions to adjust interest rate targets display some nonstationarity over time. The chosen model successfully predicts the majority of the target rate changes during the time period considered (1994–2001) and helps to explain strings of similar intervention decisions by the Fed. Based on the model‐implied optimal interest rate, our findings suggest that there is a lag in the Fed's reaction to economic shocks during this period. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
69.
论我国物流托盘标准的选择--基于商品出口市场角度   总被引:2,自引:0,他引:2  
托盘(pallet)是为了便于货物装卸、运输、保管和配送等而使用的、由可以承载若干数量物品的负荷面和叉车插口构成的装卸用垫板。它起始于20世纪30年代的太平洋战争中,当时美国军队首次使用托盘来改善货物搬运效率,保证后勤物资供应。其后,托盘在世界各国得到了广泛应用,被认为是20世纪物流产业中两大关键性创新之一。目前,美国有80%的商品由托盘运载,欧洲每年有2.8亿个托盘在企业间循环。  相似文献   
70.
循环经济的投入产出分析   总被引:1,自引:0,他引:1  
王俊  李俊霖 《南方经济》2006,7(11):14-21
本文运用投入产出理论对循环经济进行了量化分析,首先,在模型中将循环经济部门从生产部门和消除污染部门中分离开来,在投入不变的条件下,运用循环经济下的各种经济指标来研究新的投入产出关系。其次,通过比较研究的方法,来分析循环经济对整个国民经济的影响程度及对其效果进行评价。最后本文还探讨了在不引入循环生产部门的情况时循环经济的投入产出关系。  相似文献   
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