TECHNICAL NOTE: THE FORMULA APPROXIMATION FOR THE OPTIMAL CYCLE TIME OF THE NET PRESENT VALUE

This article proposes the best bounds for e^?x ?l+x subject to some constraints. With these bounds for e^?x ?l+x, the better bounds for the optimal cycle time can be developed such that the bisection algorithm locates the optimal cycle time more accurately. Finally, an example is given to illustrate all results obtained by this article.     

Option Bounds with Finite Revision Opportunities

This article generalizes the single-period linear-programming bounds on option prices by allowing for a finite number of revision opportunities. It is shown that, in an incomplete market, the bounds on option prices can be derived using a modified binomial option-pricing model. Tighter bounds are developed under more restrictive assumptions on probabilities and risk aversion. For this case the upper bounds are shown to coincide with the upper bounds derived by Perrakis, while the lower bounds are shown to be tighter.     

THE POST‐ASIAN CRISIS DROP IN INVESTMENT: THE CASES OF INDONESIA,KOREA, MALAYSIA,AND THAILAND

This study analyzes drops in East Asian investment and their determinants after the 1997–1998 Asian financial crisis. We first employ a random level‐shift autoregressive model to quantify the shift in investment ratios of four Asian economies hit by the 1997–1998 Asian financial crisis: Indonesia, Korea, Malaysia, and Thailand. We trace the major historical shifts in the levels of investment ratios and we find that the cumulated downward shifts in investment ratios during 1997–1998 for Indonesia, Korea, Malaysia, and Thailand are 6, 5, 14, and 14 percentage points, respectively. The investment ratios of most countries experienced several rebounds between 1999 and 2001, but the rebounds were too small to bring investment ratios back to their pre‐1990 levels. Having identified the episodes of investment shifts, the Bayesian Model Averaging (BMA) and several robust tests are employed to investigate the determinants of those level shifts in investment ratios. We find that real per capita gross domestic product growth and banking crises are the two most important factors contributing to shifts in the investment levels of these four crisis‐hit Asian economies. The results are useful in understanding the causes and remedies of global imbalances. (JEL C11, E22, F32, O53)     

LONG‐RUN GROWTH AND WELFARE EFFECTS OF TAX REFORM

This paper introduces an endogenously‐determined fertility rate into a Romer‐type endogenous growth model and, accordingly, investigates the effects on fertility, economic growth and social welfare of a revenue‐neutral tax reform that involves switching from an income tax to a consumption tax. We show that, in a departure from the existing literature, tax reform could be harmful, rather than favourable, to both growth and welfare, due to an endogenous fertility rate. We also conduct a simple numerical analysis to investigate under what conditions the negative effect on growth and welfare occurs.     

一种短波软件无线电台的实现

详细介绍了一种实用的短波软件无线电方案 ,并根据所提方案实现了短波软件无线电台 :利用TI公司生产的TMS32 0C4 0完成了AM、SSB、FM等短波信号的发射与接收 ,该电台的解调是在低中频基础上完成的 ,其解调算法可用于直接射频处理的场合。