软件限时开发方法的研究与应用

限时开发是快速应用开发的最佳实践之一。文章介绍了限时开发的基本概念和优点以及适用的项目范围,通过一个进销存软件的开发实例说明如何成功地应用限时开发方法。     

节约型社会解读与广义全面价值管理

本文根据节约型社会的基本内涵与经济学解读,对价值涵义及其源泉进行再认识,提出广义全面价值管理方法论。     

Assessing French nursing home efficiency: An indirect approach via budget-constrained DEA models

In this paper, data envelopment analysis (DEA) techniques are applied to the French nursing home industry in order to address two policy issues. The first involves nursing home size and returns to scale, while the second deals with the potential effects of a change in nursing home reimbursement from a flat rate to one based on the severity of case-mix. To accomplish this, our analysis expands on the existing nursing home literature to analyze technical and allocative efficiency along with budget-constrained models rather than the more common direct input-based distance function. Technical efficiency is evaluated via an indirect output distance function while allocative output efficiency is computed with a cost indirect revenue function. The findings suggest that system-wide efficiency and equity may result from coming reforms since payments would more accurately reflect resource use.     

实用电机磁场检测电路及应用

文章介绍一种简单、实用、可靠的电机欠磁失磁检测电路及应用。在电气传动系统中该电路能有效地保证电机的安全运行。     

基于粒子群优化的模糊聚类分析

基于求解实优化问题时,粒子群优化算法优于遗传算法。在基于遗传算法的模糊C均值聚类算法基础上,给出了基于粒子群的模糊C均值聚类算法,试验结果表明:该算法克服了传统的模糊C均值聚类算法的缺陷,同时在收敛速度方面明显优于基于遗传算法的模糊C均值聚类算法。     

On a clear day you might see an environmental Kuznets curve

We shed some new light on the Environmental Kuznets curve (EKC) and show how it can be viewed as a particular form of equilibrium relationship, where technology and preference parameters determine the shape of the curve. In contrast to most of the literature on the EKC, we estimate a theoretically consistent model on long-run data (Swedish sulfur emission, covering the period 1900–2002). Furthermore, we test and date structural change. The model suggests four regimes, 1900–1918, 1919–1933, 1934–1967 and 1968–2002, generating four rather different patterns for pollution over time. The policy-conclusions are consonant with Pearce’s general view about the EKC: there is no theoretical presumption that it has an inverted U shape, nor should any country try to “grow out of the environmental problems” without analyzing the benefits and costs of so doing.     

Less Government—More Wealth? On the Macroeconomics of a Smaller Public Sector in Europe

In this paper, we analyze the reactions of European economies to a fiscal policy strategy aiming at diminishing the public sector. Within the framework of the MSG3 model, a macroeconomic model of the world economy, we perform several simulation experiments to explore the effects of reducing government expenditures permanently in different phases of the business cycle. For this purpose, we combine the fiscal contraction with negative and positive, Euro Area-wide and global, supply and demand shocks. It turns out that adverse Keynesian effects on output and employment tend to be mostly weak and short-lived, whereas long-run effects on output and employment are favorable. Due to these long-run effects, the fiscal contraction policy raises welfare as measured by an asymmetric quadratic objective function. The size of these welfare effects depends on the initial situation in a non-trivial manner.     

The structural transformation and aggregate productivity in Portugal

We document the substantial process of structural transformation—the reallocation of labor between agriculture, manufacturing, and services—and aggregate productivity growth undergone by Portugal between 1956 and 1995. We assess the quantitative role of sectoral labor productivity in accounting for these processes. We calibrate a model of the structural transformation to data for the United States and use the model to gain insight into the factors driving the structural transformation and aggregate productivity growth in Portugal. The model implies that Portugal features low and roughly constant relative productivity in agriculture and services (around 22%) and a modest but growing relative productivity in manufacturing (from 44 to 110%). We find that productivity growth in manufacturing accounts for most of the reduction of the aggregate productivity gap with the United States and that a further closing of this gap can only be accomplished via improvements in the relative productivity of services. This paper was written while the authors were affiliated with the Federal Reserve Bank of Richmond. We would like to thank the editor, two anonymous referees, and participants at the Third Conference on Portuguese Economic Development in the European Context organized by the Bank of Portugal for their comments. All errors are our own.     

On the evolutionary edge of altruism: a game-theoretic proof of Hamilton’s rule for a simple case of siblings

We offer a game-theoretic proof of Hamiltons rule for the spread of altruism. For a simple case of siblings, we show that the rule can be derived as the outcome of a one-shot prisoners dilemma game between siblings.JEL Classification: A13, C70, D64Correspondence to: Oded Stark, ZEF, University of Bonn, Walter-Flex-Strasse 3, 53113 Bonn, GermanyWe are indebted to an anonymous referee and to Uwe Cantner for helpful comments and suggestions. Partial financial support from the National Institute on Aging (grant RO1-AG13037) and from the Humboldt Foundation is gratefully acknowledged.     

Foreign direct investment, competition and industrial development in the host country

This paper analyses the impact of foreign direct investment (FDI) on the development of local firms. We focus on two likely effects of FDI: A competition effect which deters entry of domestic firms and positive market externalities which foster the development of local industry. Using a simple theoretical model to illustrate how these forces work we show that the number of domestic firms follows a u-shaped curve, where the competition effect first dominates but is gradually outweighed by positive externalities. Evidence for Ireland tends to support this result. Specifically, applying semi-parametric regression techniques on plant level panel data for the manufacturing sector we find that while the competition effect may have initially deterred local firms’ entry, this initial effect has been outpaced by positive externalities making the overall impact of FDI largely positive for the domestic industry.