求解SEM极点的Kuhn法

在研究瞬变电磁场的奇点展开法中,散射物体的自然频率(极点)是一个非常重要的参数。以往人们都用迭代法或围线和分法计算物体的自然频率。本文采用Kuhn法,在不需任何初值假设的情况下,用不多的计算时间求出了精度很好的细线导体的极点。     

Migration differentials by education and occupation: Trends and variations

The effects of education on current migration propensities in the United States are examined for each age group, and an estimate is made of how these age-specific differentials cumulate over a lifetime in determining the number of times that individuals at different educational levels can expect to move over the course of their lives. The independent effects of age, education, and occupation are also examined. Two other sections investigate trends in educational selectivity of migration in the United States and international comparisons of occupational differences in migration.     

Income taxation and the allocation of market labor

The allocation of work effort within the market economy will be unaffected by taxation if all returns from labor market activity are taxed equally. However, if the earnings from certain types of market employment are taxed at relatively lower rates, labor will shift into these areas until after-tax earnings are equal across all types of employment. This paper presents evidence suggesting that income taxation induces labor to move from high- to low-tax geographic areas and from wage and salaried jobs into self-employment activities. By affecting the allocation of market labor, the income tax generates a welfare loss in addition to that resulting from the tax’s effect on total work effort.     

The influence of mumber and ages of children on residential mobility

Married couples without children are more geographically mobile than those with children, at least through age 45. Among husband-wife couples with children, ages of children exercises a consistent mobility differential; when age of family head is controlled for, families with children under 6 years old only are the most mobile both within and between counties, followed by those with children under 6 and 6–17 years old, and followed in turn by families with children 6–17 years old only. The relationship between number of children and the probability of moving within counties has a reverse J-shape for family heads at each age under 45; after age 45 the relationship assumes a more normal J shape. Number of children is inversely related to the probability of migrating (moving between counties) for husband-wife families in which the husband is under 35; after age 35 the relationship is erratic. The effect of ages of children generally holds for each size of family. Female family heads with children are generally more geographically mobile than male family heads (wife present) at the same age and with the same number and ages of children present.     

中小企业集群战略与西北区域经济发展

针对西北经济落后的现状,本文在讨论聚集经济各种优势的基础上,认为进行新的定向劳务输出是西部欠发达地区实施中小企业集群战略的重要措施。     

Fertility patterns among religious groups in Canada

The U shape that has been traced out by the crude birth rate in the United States and Canada is well known. Falling birth rates reached a low point in the mid-1930’s; the rate rose to a peak in 1947 and remained high through the 1950’s. In terms of cohorts, completed family size was smallest for women born around 1910, whose childbearing was concentrated in the 1930’s. With data from the 1961 census of Canada, trends in cohort marital fertility by religion are examined. The U pattern appears for both Protestants and Jews. For Catholics, a reversal in the downward trend of family size had not appeared by 1961, although the U pattern can be discerned for some subgroups such as Catholics living in big cities and persons of Irish ancestry. In the United States, however, changes in family size for all three religious groups and both whites and nonwhites follow the U pattern. Religious differentials in family size in Canada have been decreasing, but they remain much larger than either religious or color differentials in the United States, which show no decrease. The distinctive features of Catholic fertility in Canada are most pronounced among the regionallyconcentrated French Canadians, suggesting an interplay of religious, regional, and ethnic influences.     

Do these guys know why they're applauding?

Contained in Title IV, Section 6102, of the Omnibus Budget Reconciliation Act of 1989 are more than 21 pages of legislative language designed to require the Health Care Financing Administration (HCFA) to set all physicians' fees for services delivered under Part B of Medicare commencing January 1, 1992, and phased in over the following four years. In addition, balance billing dollar limits keyed to the regulated rates are set forth, as are "Volume Performance Rates of Increase," a reincarnation of a vehicle previously known as "Expenditure Targets."     

民间借贷风险的法律规制

作为正规金融的有益补充,民间借贷在服务民间融资、推动中小企业发展方面发挥了重要的作用.由于体制、制度、监管等多方面的原因,民间借贷面临着直接、间接两个方面的风险.市场无法自行化解这些风险,政府应当发挥有形之手的作用,在体制、制度、机制各层面强化、完善对民间借贷风险的规制.     

小型猪急性心肌梗死模型建立过程中电风暴的不同处理方法比较

目的:比较小型猪急性心肌梗死(acute myocardial infarction,AMI)模型建立过程中心室电活动极度不稳定所导致的心室电风暴(ventricular electrical storm,VES)的不同处理方法的疗效?方法:小型猪32只,分为4组:A组(未干预组)7只?B组(胺碘酮干预组)8只?C组(美托洛尔干预组)8只?D组(胺碘酮联合美托洛尔干预组)9只?各组均在氯胺酮及戊巴比妥钠全麻下采用球囊封堵法封堵前降支中远段,缺血预适应3~4次?持续封堵60 min?再灌注30 min建立AMI模型?结果:4组中3只意外死亡,缺血预适应期?持续封堵期?再灌注期4组动物均出现室性心律失常,B?C?D 3组与A组相比有减少趋势但无统计学差异(P > 0.05);4组动物VES比较,B?C 2组与A组相比有减少趋势但无统计学差异,D组与A组相比明显减少,差异显著(P = 0.005);4组死亡情况比较,各组与A组相比无统计学差异;缺血预适应期与再灌注期易于发生心律失常?VES及死亡,但不同时期室性心律失常的发生差异并不显著(P > 0.05)?结论:AMI模型建立过程易于发生VES导致实验动物死亡;胺碘酮联合美托洛尔可有效抑制猪AMI模型建立中电风暴的发生,提高建模成功率?