DIRECT RESONANCE OF TURBULENT BOUNDARY LAVER OVER COMPLIANT WALLS

１．　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｍａｉｎｇｏａｌｏｆｔｈｉｓｐａｐｅｒｉｓｔｏｅｘｐｌｏｒｅｔｈｅｐｏｓｓｉｂｉｌｉｔｙｔｏｌｅａｒｎｍｏｒｅａｂｏｕｔｔｈｅｍｅｃｈａｎｉｓｍｏｆｔｕｒｂｕｌｅｎｔｂｏｕｎｄａｒｙｌａｙｅｒｆｌｏｗｉｎｔｅｒａｃｔｉｏｎｓａｎｄｉｔｓｅｆｆｅｃｔｓｏｎｃｏｍｐｌｉａｎｔｗａｌｌｐｅｒｆｏｒｍａｎｃｅ．Ｔｈｅｒｅａｒｅｃｅｒｔａｉｎｐｒｅｒｅｑｕｉｓｉｔｅｃｏｎｄｉｔｉｏｎｓｔｏｆｕｒｔｈｅｒｔｈｅｓｔｕｄｙｏｎｔｈｅｍｅｃｈａｎｉｓｍ，ｉ．ｅ．ｔｈｅｃｏ…     

高温超导进入实用阶段

高温超导技术可能在未来几年里产生重大影响。可以应用的领域包括电力电缆、配电变压器、中压开关设备的短路电流限制器以及贮能系统。     

“绿色高尔夫”酒店

他们高贵而富有,他们拥有Punta Cana海滩高尔夫度假酒店,他们要挑战传统的商业模式。     

Population,agriculture, and the environment in Africa

An overview is provided of the World Bank study about the interaction between rapid population growth, poor agricultural performance, and environmental degradation. The links between these 3 phenomena are identified as traditional methods of crop and livestock production, land tenure systems, women's responsibilities, and methods of forest use. When land was abundant and capital limited, pastoralism, shifting cultivation, and setting aside fallow land was possible. Mobility and allowances for natural regeneration of vegetation could not continue with rapid population growth. Permanent settlements developed but cultivation methods remained the same; the result was deterioration of soil fertility, low yields, and erosion of soil as occurred in Rwanda, Burkina Faso, and parts of Nigeria. Technological innovation has been slow and poor roads have interfered with a market oriented economy. Inappropriate pricing, exchange rates, and fiscal policies also prevent productivity gains. A heavy demand is placed on women's time. Demand for children is high and is stimulated by environmental degradation, food insecurity, land tenure systems, and cultural traditions. Child labor is needed. The demand for contraception is 30-50% in North Africa, 36-55% in Asia, and 40-60% in South America. Land ownership problems have arisen under community ownership and between herders and settlers. Solutions have ranged from land nationalization and arbitrary designation of individual ownership. Open access situations have developed and lent themselves to exploitation. Fuelwood needs have exacerbated the destruction of forests. Commercial logging accounted for 10-20% of the forest loss. New approaches are needed to link cross-sectionally population, the environment, an agriculture. Emphasis should be on resource conservation, family planning, and environmentally benign intensive farming. Agricultural production needs to grow at 4%/year, fertility lowered by 50% over 30 years, and deforestation slowed. Women's time constraints should b alleviated and productivity improved. Open access and state ownership should be stopped.     

Demographic changes and local public expenditure in a macroeconomic perspective. Some Norwegian examples

The impact of demographic aging and changes in the age structure on local government expenditures for social services in Norway is analyzed and projected. "To model the production of the local government sector, we have developed a macro model which reflects the coverage of different services according to demographic characteristics and standards defined as man-hours per client.... The results of a simulation show that demographic changes are of minor importance for local government expenditures in most sectors when compared to changes in standard and coverage rates....Results [also] indicate that a shift in standards and coverages in different client sectors would have rather important effects on the Norwegian economy."     

Gut issue

Unions are willing to strike over it, and companies are ready to draw the line, too. Now both sides are turning to Congress to fix the health insurance mess. This is the first of two articles on responses to the growing health care crisis. A report on state efforts begins on p. 708.     

The relations among child quality,family structure,and the value of the mother's time in Malaysia

A model of the determinants of child quality and of the value of a woman's time is developed and tested using data from the Malaysian Family Life Survey of 1976-1977. Child quality is measured by educational attainment; factors influencing the value of the mother's time include size and age composition of household, family income, education, and hours worked. The results indicate that size and age composition of household affect a woman's asking wage. However, more data are needed before the effects of family structure on schooling can be measured with confidence.