椭圆半带滤波器及其在小波包谐波分析中的应用

小波包分解因为具有较高频谱分析的精度，在电力系统谐波检测中得到了广泛的应用．但其复杂的计算使它在实时的测量中受到了限制．现提出了将IIR椭圆半带滤波器应用于小波包谐波分析中的新方法，通过研究表明，该算法可以将复杂的计算减少到与快速傅立叶变换（FFT）同等数量级上．仿真和实验结果进一步表明了该算法的有效性．     

External spillovers, internal spillovers and the geography of production and innovation

We consider a three-location duopoly model such that (i) firms choose production and innovation locations before (Bertrand) competition takes place and (ii) there are internal and external knowledge spillovers. We show: (1) agglomerations where firms earn negative profits may exist when there are both external and internal knowledge spillovers; (2) greater external spillovers do not necessarily favor agglomeration; (3) decreasing communication costs tend to favor agglomeration; (4) there are exactly two types of agglomeration equilibria: either both firms innovate in the agglomeration, or there is an innovator and an imitator; and (5) if there is a location where both firms produce, then innovation must take place in this location.     

数字视频频编码压缩技术解析

文章介绍了ISO／IEC制定的MPEG—x和ITU—T制定的H．26x两大系列视频编码国际标准视频编码压缩技术并具体介绍了7种标准的实际应用。     

Consumer Expenditures and Home Production at Retirement – New Evidence from Germany

Abstract. This paper investigates consumer expenditures of German households pre‐ and post‐retirement. The widely observed distinct drop in spending upon retirement entry poses an empirical puzzle since life cycle theory predicts smoothing of the marginal utility of consumption over time. As one explanation, I explore the role of home production as a substitute for consumer expenses. Taking a combined look at consumer expenditures and time use pre‐ and post‐retirement, I find a significant drop of about 17% of pre‐retirement expenses at retirement which coincides with an increase in time spent on home production of an additional 89 minutes per day, accounting for 21% of average home production.     

The Contribution of Associate's Degree Holders to U.S. Earnings,Labor Quality,Productivity, and Overall Economic Growth

There is substantial evidence on the importance of education as a driver of earnings, productivity, and economic growth. However, knowledge of the specific role of associate's degrees in U.S. economic growth is limited. We analyze the sources of U.S. economic growth and identify the contribution of associate's degree holders to improvements in earnings, labor quality, productivity, and overall economic growth. We find evidence that substitution toward workers with associate's degrees has increased U.S. earnings, aggregate labor quality, and productivity, and that these effects are concentrated in the health care, trade, and government sectors. While the average educational attainment of people entering the labor force has plateaued, our results suggest that shifting workers from some college to associate degrees could improve earnings, the quality of the workforce, productivity, and growth, potentially without more time spent in school.     

Understanding the size and profitability of firms: The role of a biological factor

In a large sample of entrepreneurs, 2D:4D (second-to-fourth digit) ratio and managerial performance are studied. Entrepreneurs with lower ratio manage larger firms, manage larger firms when acquire control and experience faster average growth. Firms run by high prenatal testosterone entrepreneurs have lower profitability as measured by return on assets and return on sales. Prenatal testosterone is correlated with elicited measures of entrepreneurial skills, like work effort and optimism and the latter are correlated with firm size. This evidence suggests entrepreneurial ability has a biological component and is consistent with models of the size distribution of firms based on entrepreneurial ability.     

2．4GHz无线网络在校园网络建设中的应斥--山东工业职业学院无线校园网络的设计方案

介绍了无线网络的基本原理、技术特点,在此基础上结合山东工业职业学院的实例形式阐述了山东工业职业学院无线校园网络建设的设计方案,包括覆盖范围、网络安全、认证模式以及收费策略等,可以看出,无线网络克服了有线网络无法克服的困难,对于扩充学校网络接入能力,提高网络资源的利用率,推进学校信息化建设,具有不可替代的作用。     

Playing away to win at home

This paper presents a model of the interaction between two rival firms based in the same country. Each firm must decide how to serve a foreign market (export or foreign production) and how much to invest in a corporate-wide asset that reduces production costs and/or augments the willingness-to-pay for their product. In this scenario, the firms’ foreign direct investment decisions are interdependent. Furthermore, strategic motives for FDI relate to a firm's domestic, as well as foreign, market profits. One possibility is that a firm sets up overseas production even though its foreign market profits would be higher by exporting.     

The impact of R&D on value added for domestic and foreign firms in a newly industrialized economy

This study compares the impact of R&D on value added between domestic and foreign firms in Singapore. The analysis is based on a comprehensive panel database from 1993 to 1999 provided by the Singapore Government. Our results found that R&D investments of foreign firms generated higher value added than those of domestic firms, and that the difference in value added contributed by R&D was moderated by the type of R&D and the technological level of industry. The study supports the argument that the ownership advantages possessed by foreign firms, relative to domestic firms, have positive effects on R&D performance.     

Informality,public employment and employment protection in developing countries

This paper proposes an equilibrium matching model for developing countries’ labor markets where the interaction between public, formal private and informal private sectors are taken into account. Theoretical analysis shows that gains from reforms aiming at liberalizing formal labor markets can be annulled by shifts in the public sector employment and wage policies. Since the public sector accounts for a substantial share of employment in developing countries, this approach is crucial to understand the main labor market outcomes of such economies. Wages offered by the public sector increase the outside option value of the workers during the bargaining processes in the formal and informal sectors. It becomes more profitable for workers to search on-the-job, in order to move to these more attractive and more stable types of jobs. The public sector therefore acts as an additional tax for the formal private firms. Using data on workers’ flows from Egypt, we show empirically and theoretically that the liberalization of labor markets plays against informal employment by increasing the profitability, and hence job creations, of formal jobs. The latter effect is however dampened or even sometimes nullified by the increase of the offered wages in the public sector observed at the same time.