基于过程划分的可再生能源技术扩散模型

把握技术扩散的机理和主要特征是可再生能源发展规划和管理优化的基础。本文基于信息扩散、技术经济、社会认可度等因素对可再生能源技术的影响及其作用机理分析,根据投资者状态变化,将技术扩散过程划分为技术获悉、效益计算和技术认可三个阶段,构建了可再生能源技术扩散(即潜在投资者转变为最终投资者)过程的数理模型。探讨了可再生能源技术扩散的速度有限性、政策效率递减性以及区域差异性三个关键特征,结合算例验证模型并进一步分析了技术扩散的不同驱动力,从而为可再生能源技术扩散机理政策制定提供理论支持和意见建议。     

中国的人口转变完成了吗?

本文依据 1 998年我国人口一些重要指标所达到的水平 ,并通过与发达国家同类指标达到相同或相近水平时间的比较 ,判定我国人口转变过程在 2 0世纪末已经结束 ,人口增长从低增长走向零增长和人口结构性变动成为调节人口增长势态的主要因素这两个后人口转变时期人口变动的基本特征在我国已经开始显现出来     

When women veterans return: The role of postsecondary education in transition in their civilian lives

Objective: The purpose of this study was to assess the current state of postsecondary educational settings’ outreach to military women who become students postservice. Participants: Data for the present cross-sectional study were obtained from the American College Health Association’s (ACHA) 2011–2014 National College Health Assessment II (NCHA). Methods: Demographic characteristics of the study sample were explored by calculating frequencies and percentages by military service status. Research questions were explored with Fisher’s exact test, maximum likelihood multiple logistic regression, as appropriate. Results: Women service member and veteran students received health information from their university/college less often than women students with no military experience on the following topics: alcohol and other drug use, depression and anxiety, sexual assault and relationship violence prevention, and stress reduction. Conclusions: The findings of this research identified clear gaps in service provision for women student veterans on college campuses and provided some possible models for intervention development.     

Everything for the Children: Orphans Growing Up in Informal Adoptive Families in China

Most orphaned children in China are cared for by their extended families or become state wards under the guardianship of child welfare institutions. Some exceptions are children who are found and cared for by families in the community, without a formalized adoption or foster relationship. In some locations, institutions now accept guardianship for these children and support the informal adoptive family to continue to care for them. This article examines the outcomes for these children as they became young adults by comparing these 12 children raised within the system as they approach or have approached young adulthood (now aged 16–40 years-old). Some of the participants were either informally adopted or lived in institutional care. The results of this study found that the family environment was more conducive to the young people’s wellbeing as they approached or entered adulthood. The participants raised in informal care appeared to be treated similar to the biological children in these families. When the institution formalized the state guardianship responsibility, it also meant the families had state resources for support to protect the children’s rights to economic security, education, health care, and social participation. This practice by the institution supported the addition of informal adoption, as one step closer to permanency than foster care. Future implications include considering this option to help promote the family system assisting these children, families, and the state.     

Quick,uncertain, and delayed adults: timing,sequencing and duration of youth-adult transitions in Canada

The transition from youth to adulthood in western societies has become more prolonged and complex as traditional societal norms have lost influence. Using retrospective data from a cohort of 43-year-old Canadians surveyed in 2010 (n?=?405), we mapped the timing, sequencing, and duration of ‘first stage’ youth-adult transitions (leaving home, finishing formal education, obtaining a full-time job) and ‘second stage’ youth-adult transitions (marriage, parenthood, home ownership). Latent profile analysis identified five distinct transition profiles – norm-setters, quick adults, uncertain adults, adult students, and delayed adults – with different amounts and timing of post-secondary educational investment playing an important profile-shaping role. Although youth-adult transitions have become less standardized and more individualized, especially for first stage transitions, these transitions are still quite structured and continue to be affected by gender and family socioeconomic status.     

Father's Migration and Leaving the Parental Home in Rural Mozambique

Migration is an increasingly common global phenomenon and has important implications for the well‐being of family members left behind. Although extensive research has examined the impact of parental labor migration on school‐age children, less is known about its effect on adolescents. In this study, the authors used longitudinal survey data collected in rural Mozambique (N = 515) to assess the association between father's migration and adolescent children's leaving the parental home, an important component of the transition to adulthood. The results showed that father's migration delays home‐leaving for adolescent girls and that these effects are not mediated by school enrollment. The results for boys were inconclusive. The authors also found that remittances and longer durations of paternal migration were negatively associated with the transition out of the home. On the basis of the findings, they argue that father's migration delays girls' marriage.     

中国经济转型期城镇少数民族教育收益率的实证研究

文章分别使用了OLS方法和分位回归技术,考察了1995—2007年间中国城镇少数民族教育收益率的总体水平及其长期变化趋势,并将之与汉族进行了比较,发现在经济转型期,中国城镇居民教育收益率总体上呈逐年上升趋势,少数民族与汉族之间的教育收益率没有显著差异。政策的力量与市场的力量有机结合、相互叠加,是转型时期中国城镇少数民族的地位并没有发生逆转的重要原因。与汉族相同,少数民族的教育收益率随着收入分位点提高而逐渐减小,即收入水平越高,教育收益率越低。     

An Empirical Test of a Neo-Malthusian Theory of Fertility Change

Some neo-Malthusians regard fertility as being kept in check by scarcities and constraints and, conversely, as being raised by economic prosperity. Since out-migration to developed countries and the receipt of food aid from developed countries relax the constraints imposed by a country’s carrying capacity, both will have a positive effect on fertility rates in developing countries. Moreover, better economic prospects will also raise fertility, all other things equal. This article provides an empirical test of these hypotheses derived from a neo-Malthusian theory of fertility change. The results fail to confirm the theory and often contradict it.

Neighborhood change from the bottom Up: What are the determinants of social distance between new and prior residents?

An important source of neighborhood change occurs when there is a turnover in the housing unit due to residential mobility and the new residents differ from the prior residents based on socio-demographic characteristics (what we term social distance). Nonetheless, research has typically not asked which characteristics explain transitions with higher social distance based on a number of demographic dimensions. We explore this question using American Housing Survey data from 1985 to 2007, and focus on instances in which the prior household moved out and is replaced by a new household. We focus on four key characteristics for explaining this social distance: the type of housing unit, the age of the housing unit, the length of residence of the exiting household, and the crime and social disorder in the neighborhood. We find that transitions in the oldest housing units and for the longest tenured residents result in the greatest amount of social distance between new and prior residents, implying that these transitions are particularly important for fostering neighborhood socio-demographic change. The results imply micro-mechanisms at the household level that might help explain net change at the neighborhood level.     

Building home on a fault line: Aging out of child welfare with a serious mental health diagnosis

Youth aging out of foster care are at high risk for homelessness. This research explains how and why homelessness occurs among youth with serious mental health struggles after aging out of residential and transitional living programmes. Using a longitudinal constructivist grounded theory design, we analyse 20 in‐depth interviews exploring youth's transition experiences and perceptions of transition success within 4 months of emancipation and at 6 and 12 months postemancipation. Monthly 15‐min check‐ins prevented attrition. A three‐phase transition process was observed driven by participant desires and actions to cultivate psychological home through establishing physical home alone away from social networks. Pre‐emancipation, the promise of home was privacy and opportunity for self‐redefinition. Shortly after emancipation, home became a physical and social space to be, a valuable resource to share and a demonstration of personal transition success. However, later in the year postemancipation, maintaining physical home proves nearly impossible given the risk context. Findings speak to how and why youth aging out appear overly self‐reliant upon emancipation. Cultivating a psychological sense of home has practice implications for child welfare providers who aim to prepare youth to live independently postemancipation.