A SPATIALLY-VARYING PARAMETER MODEL OF AFDC PARTICIPATION: EMPIRICAL ANALYSIS USING THE EXPANSION METHOD*

Spatial variation in the importance of determinants of participation in the Aid to Families with Dependent Children program (AFDC) is investigated for the U.S. Casetti's Expansion Method is applied to the two-dimensional space domain by making the model's parameters a function of state x–y centroids. The spatially-varying parameter model suggests that the black population's association with participation is lowest in the Southeast and Northwest and greatest in the Southwest and Northeast.     

Equity vs. Efficiency: Public Capital Investment in Ohio, 1988–1992

Recent research on the role of public capital in the economy focuses primarily on assessing its economic, and sometimes spatial economic, impacts. Access to more detailed and disaggregate data than typically used in these analyses allows us to take a fresh perspective on the often conflicting goals of interregional equity and aggregate efficiency. Using the state of Ohio as a case study, and classic definitions of equity and efficiency, we assess the correspondence between distributions of infrastructure investment and the social/economic distress they are intended to alleviate. Traditional map and statistical analysis combined with a graphical device we call the variegated distribution plot reveals that, in both rates and levels, investment is highest in areas of greatest distress. Both patterns are consistent with equity-driven investment distributions.     

中国生产控制型产业减排的居民福利和区域影响

基于SAM均衡建模方法,建立面向居民福利研究的中国动态多区域社会公平CGE政策模拟模型,对比分析自然情景、生产控制型减排政策情景和最优增长情景下的区域和居民福利变化。研究发现减排政策存在明显的增长率区域分异,这将破坏在自然增长下存在的区域收敛力,导致中国区域之间的差距再度被拉大。面向减排的投资控制政策短期对于居民收入的不利影响较小,但长期影响不容忽视,需要进行居民收入保护。由于城镇退休居民和农村劳动居民已经具备针对性的养老保障政策和“三农政策”保护收入增长,其总体福利受减排政策的冲击较小,因此缺乏相应政策支持的城镇劳动居民应该是收入保护的优先考虑群体。模拟显示减排政策更有利于代际和城乡人均收入差距的缩小,但考虑到减排带来的绝对收入水平下降,不能过于乐观估计这种差距缩小效应。     

公益性标准地图服务平台的建设与思考

以《地图管理条例》实施为契机,以服务公众和繁荣地图发展为宗旨,创新地图服务模式和机制,设计研发了公益性标准地图服务平台,发布了首批公益性标准地图。平台旨在为公众提供正确的地图数据和实用的地图服务,一方面提供了免费的中国地图、世界地图、专题地图等标准地图的下载服务,另一方面实现了公众在线自助制图功能。笔者以构建国家级公益性标准地图服务平台为目标,对如何为公众提供更优质的公益性地图服务进行了深入思考。     

Estimation of enterococci input from bathers and animals on a recreational beach using camera images

Enterococci, are used nationwide as a water quality indicator of marine recreational beaches. Prior research has demonstrated that enterococci inputs to the study beach site (located in Miami, FL) are dominated by non-point sources (including humans and animals). We have estimated their respective source functions by developing a counting methodology for individuals to better understand their non-point source load impacts. The method utilizes camera images of the beach taken at regular time intervals to determine the number of people and animal visitors. The developed method translates raw image counts for week days and weekend days into daily and monthly visitation rates. Enterococci source functions were computed from the observed number of unique individuals for average days of each month of the year, and from average load contributions for humans and for animals. Results indicate that dogs represent the larger source of enterococci relative to humans and birds.     

莱芜市钢城区畜禽养殖用地管理的现状及建议

随着我国畜牧业的发展,饲养方式和结构发生了很大的变化,对规模化养殖提出了新的要求,该文结合莱芜市钢城区实际,对畜牧养殖用地方面当前存在问题进行了系统的分析,对今后的用地管理提出了切实可行的建议。     

Local Labor Market Restructuring and the Employment of Welfare Recipients in Los Angeles County

Although welfare rolls have dropped considerably in recent years, most welfare recipients who find work are employed in low-wage, insecure jobs. The problem of "working poverty" is especially acute in large city-regions such as Los Angeles, where local labor market restructuring has created an expanding, low-wage economy, increasingly dependent on immigrant labor. This paper analyzes the employment outcomes of 6,931 women who completed the county's welfare-to-work program in 1996. I evaluate their earnings, labor market segmentation, and job stability. The results show that women were highly concentrated in low-wage service jobs and experienced high levels of turnover and unemployment. Many were unable to obtain employment in the formal labor market. I argue that the struggles of the working poor in a growing regional economy are explained not solely by human capital limitations, but by processes of local labor market restructuring that have contributed to widespread economic insecurity in Los Angeles County.     

Bartering for Basics: Using Ethnography and Travel Diaries to Understand Transportation Constraints and Social Networks Among Working-Poor Women

Working-poor women face many challenges in their quest for economic self-sufficiency. Although welfare reform promises jobs, women do not have equal access to necessary services, including transportation. With the 2010 reauthorization of TANF (Temporary Asssistance for Needy Women), there is a need to develop a methodology that uses qualitative individual-level data to evaluate whether public transportation will serve working-poor single mothers in this quest for self-sufficiency. Using ethnography, travel diaries, and a GIS for a sample of women in the process of leaving welfare in Knoxville, Tennessee, travel behavior is examined both qualitatively and quantitatively in order to understand why they rarely use public transportation. Further research into the ways these women move around in a sprawling, medium-sized city reinforces and seeks to understand the extensive social networks working-poor mothers rely on. These women create communities of spatial necessity, bartering for basic needs to overcome transportation constraints.     

论人与自然的和谐

在剖析人与自然双螺旋演化机理的基础上 ,着重利用耗散结构和协同学理论探讨了人与自然和谐的规律、准则和策略 ,提出了一些新的理论观点和模型方法 ,旨在能裨益于可持续发展的理论、方法和实践应用研究     

生物多样性遥感研究进展

随着遥感技术和新型传感器的发展,遥感已成为目前区域或全球生物多样性研究的重要方法。综述了目前国内外生物多样性遥感研究的最新进展;分析了遥感生物多样性研究的主要理论基础,包括光谱变异假说、生产力假说和种—面积关系理论等;总结了利用高空间和高光谱分辨率遥感数据直接监测生物物种及其多样性的进展与局限性;基于遥感反演的不同环境变量进行生物多样性模拟和预测是目前最常用的方法,对其进行了较详细的分析,并介绍了相关模型的发展。最后,总结了该方法在我国的应用局限,指出增进学科合作、将遥感方法与生态学理论和模型相结合、重视地面验证数据的使用将是生物多样性遥感研究的发展趋势。