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1.
Influence of vegetation composition on runoff in two simulated green roof experiments 总被引:2,自引:1,他引:1
Despite the fact that green roofs are based upon living systems, the majority of published research literature contains little
specific information on the contribution of plants to the various functions and properties of green roofs. Furthermore, there
has been little investigation of the influence of the composition of vegetation on the physical properties of a green roof
system. This paper reviews previously published material that throws light on the role of vegetation composition on green
roof function, with particular regard to rainwater runoff. Two experiments at the University of Sheffield, UK, are considered
in detail: (a) An outdoor lysimeter experiment that investigated the quantity of runoff from trays containing 100 mm of growing
medium and combinations of grasses and forbs, together with bare substrate, and (b) a greenhouse experiment using simulated
rainfall to estimate the amount of rainfall intercepted by different vegetation types. In both cases the vegetation ranged
from simple monocultures of forbs and grasses through to complex mixtures of both. In both cases, the composition of the vegetation
was found to significantly affect both the amount of water retained and released from the system. 相似文献
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3.
Gender-specific labor market conditions and family formation 总被引:3,自引:2,他引:1
Ayako Kondo 《Journal of population economics》2012,25(1):151-174
Slack labor market conditions for women relative to men increase the marriage rate in the USA. This paper examines the long-term consequences of such marriages. Despite the significant effect on marriage timing, labor market conditions experienced in youth do not affect the probability that a woman will marry by the age of 30. Further, labor market conditions at the time of marriage are uncorrelated with the probability of divorce, spouses?? characteristics, or the number of children. These findings suggest that labor market fluctuations induce only intertemporal adjustments for marriage timing without affecting reservation match quality or total fertility. 相似文献
4.
We investigated the species composition of a fragmented forest in Nishinomiya Shrine, southeastern Hyogo Prefecture, Japan.
Two escaped ornamental species, Trachycarpus fortunei and Ligustrum lucidum, and bird-dispersed deciduous trees were invading the evergreen broadleaf forest. Invasive and bird-dispersed deciduous species
were most abundant along the outer edge of the forest. In 2005, restoration measures were taken to remove all individuals
of T. fortunei from the forest. We estimated that, biomass density and leaf area index (LAI, leaf area per unit ground area) of T. fortunei were 0.23 kg m−2 and 0.77, respectively, which accounted for 8.9% and 27.9% of the biomass density and LAI, respectively, of the entire forest.
After removal, canopy openness increased in the understory. However, the understory lacked seedlings and saplings of native
species, indicating that active re-vegetation may be needed to accelerate reestablishment of native species in areas that
were heavily invaded by T. fortunei. This study represents one of the first examples of active vegetation management in shrine/temple forests in Japan. 相似文献
5.
Ayako Komine 《International migration (Geneva, Switzerland)》2018,56(5):106-122
The Japanese government maintains that the country admits only skilled economic migrants. Its statistics tell a different story. Skilled and low‐skilled economic migrants are admitted in equal measure. The aim of this article is to explain the dissonance between the government's policy rhetoric and policy outcome by turning to policy output. To this end, I quantitatively analyse immigration admission channels for economic migrants, using Ruhs' Openness and Rights Indicators (2013). The main findings not only go against much of what we believe about Japan but helps us reach a more nuanced understanding of its immigration policies. I demonstrate that Japanese immigration admission policies have become more open towards de facto low‐skilled economic migrants over time and are more open to de facto low‐skilled economic migrants than to de jure skilled economic migrants. Instead of openness, the gains made by certain groups of de jure skilled economic migrants have been exclusive immigration privileges related to permanent residence and family sponsorship. 相似文献
6.
Graduating from college during a recession has persistent negative effects on labor-market outcomes. This study assesses the welfare impact of a recession at entry by analyzing family formation behaviors and asset holdings. Scrutiny of the National Longitudinal Survey of Youth 1979 (NLSY79) reveals that despite a decline in hourly wages, business cycle conditions at entry to the labor market do not affect family formation, car or home ownership, or net asset holdings in the long run. Evidence suggests that individuals who graduate in bad times tend to move to states with lower living costs to secure living standards. (JEL E21) 相似文献
7.
In Japanese, English CVC monosyllables usually show consonant gemination after obligatory vowel epenthesis (e.g. 'put' becomes 'putto'). The katakana syllabary, which is a good reflection of pronunciation, allows us to study very quickly how a number of native speakers and learners at various levels handle novel loanwords. We show that, while learners do not geminate at as high a rate as native speakers do, they improve over years of study. More interestingly, learners use another strategy, namely vowel lengthening (e.g. 'puuto'), to represent these items, a compensatory strategy, we believe, related to their perception of the proper number of morae to be rendered in the output. We show how Broselow and Park's (1995) account of mora conservation will not handle the complexity of these data, particularly learner performance in the gemination of unstressed syllables, and we provide a variable account rather than one which suggests that parameters are set to a native speaker, learner, or mixed setting. Additionally, we show the surprising influence of gender in some areas of learner performance, a reflex, we believe, of the type of male students more typically registered in Japanese language classes at the university level. 相似文献
8.
Ninety-one Japanese managers and professionals on international assignments in the London offices of trading houses and insurance companies responded to a wide-ranging survey on work and non-work adjustment. Dependent variables included standardized measures of adjustment, well-being, mental health and modes of adjustment (personal change and role innovation). In comparisons with samples from other studies, the expatriates experienced lower work well-being and mental health, and, compared with a sample of United Kingdom domestic job changers, engaged in less role innovation but recorded higher personal change, especially in their values. Predictor variables, including predeparture experience, family factors, self-rated job performance, self-efficacy, work-non-work spillover, social interaction and perceived company purpose in the assignment, were found to be differentially related to outcome measures. A new method of retrospectively recording changes in feelings over time in the work and non-work domains was also applied, supplying tentative evidence for a negative shift in affect on arrival, especially in the non-work domain, and a further fall after arrival, especially in the work domain. In most cases, this latter dip was followed by a recovery, providing some evidence in favour of the U-curve hypothesis. Implications for theory and practice are reviewed. 相似文献
9.
Ko A Takasaki K Chiba Y Fukahori H Igarashi A Takai Y Yamamoto-Mitani N 《Journal of elder abuse & neglect》2012,24(1):1-16
This study examined the experiences of staff members from seven Japanese hospitals who had been treated aggressively by older dementia clients. Altogether, 170 questionnaires were analyzed. In the past year, 75.3% and 63.5% of staff members had experienced physical and verbal aggression, respectively. Working numerous night shifts, working shifts other than 3-shifts, and being allotted assignments with clients who had a lower average level of physical capacity were the factors associated with recurrent client aggression. Those staff members who spent adequate time caring for their clients, who gained client consent before providing care, and who tried to build a trusting relationship with their clients were found to have experienced less aggression. Burnout, which is likely to enhance the risk of the staff mistreatment and neglect of older clients, was found to be higher among those who experienced aggression. 相似文献
10.