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1.
Kajihara Kazumitsu Yamaura Yuichi Soga Masashi Furukawa Yasuto Morimoto Junko Nakamura Futoshi 《Urban Ecosystems》2016,19(1):523-534
Urban Ecosystems - Biodiversity conservation and restoration in cities is a global challenge for the 21st century. Unlike other common ecosystems, urban landscapes are predominantly covered by... 相似文献
2.
This paper formalizes the dynamics of the informal sector with a special emphasis on the levels of labor market competitiveness
in the formal and informal sectors. Specifically, it analyzes the effects of improved productivity and higher entry costs
into the formal sector on the size of the informal sector for different degrees of competitiveness in the labor markets. We
show that when the informal labor market is competitive while the formal labor market is not, lower production technology
in the formal sector or a higher entry cost reduces the size of the informal sector in the long run. 相似文献
3.
This paper simultaneously measures the rate of time preference and the coefficient of risk aversion, as well as investigates the interdependencies of four addictive behaviours: smoking, drinking, pachinko (a popular Japanese form of pinball gambling), and horse betting among a sample of the Japanese population. We reach two main conclusions. First, there are significant interdependencies among the four addictive behaviours, in particular between smoking and drinking and between gambling on pachinko and the horses. Second, we conclude that the higher the time preference rate and the lower the risk aversion coefficient becomes, the more likely individuals smoke, drink frequently, and gamble on pachinko and the horses. 相似文献
4.
The Bates–Watts relative curvature measure can assess the validity of the linearized approximation in nonlinear regression models. However, it is developed based on an ordinary nonlinear regression in which the observation is assumed to be homoscedastically and normally distributed. In this article, we extend the original Bates–Watts relative curvature measure to one that can be applicable to nonlinear regression with heteroscedastic or non normal data, based on the transformation-both-sides (TBS) approach. In pharmacokinetic models, a diagnostic use of their measures is illustrated. By means of a simulation experiment, the performance of the relative curvature measure for the TBS approach is evaluated. 相似文献
5.
AbstractWe suggest shrinkage based technique for estimating covariance matrix in the high-dimensional normal model with missing data. Our approach is based on the monotone missing scheme assumption, meaning that missing values patterns occur completely at random. Our asymptotic framework allows the dimensionality p grow to infinity together with the sample size, N, and extends the methodology of Ledoit and Wolf (2004) to the case of two-step monotone missing data. Two new shrinkage-type estimators are derived and their dominance properties over the Ledoit and Wolf (2004) estimator are shown under the expected quadratic loss. We perform a simulation study and conclude that the proposed estimators are successful for a range of missing data scenarios. 相似文献
6.
Karen Louise Smith Masashi Crete-Nishihata Thecla Damianakis Ronald M. Baecker Elsa Marziali 《Journal of Technology in Human Services》2013,31(4):287-306
The multimedia biography tells the story of the life of an elderly person with a cognitive impairment in motion picture format. The multimedia biography combines family photographs, film clips, audio narration, and music. It is intended to be screened on an ongoing basis to provide spaces for reminiscence and communication between cognitively impaired persons and their families. Using a production process in which we collaborated with family caregivers, we created 12 multimedia biographies for persons having Alzheimer's disease or mild cognitive impairment. This article describes our production and screening processes. We also share lessons learned from the multimedia biography research to assist practitioners, families, or researchers who wish to use similar technologies and processes for eliciting and sharing life stories. 相似文献
7.
Hideaki Goto 《Journal of Socio》2011,40(6):806-814
This paper theoretically analyzes a situation wherein adults’ decisions on child labor are affected not only by materialistic utility but also by a social norm against child labor. The adult thus faces a tradeoff; on the one hand, household income rises if she sends her child to work. On the other hand, the adult suffers disutility from violating the social norm in so doing. We also suppose that the extent of disutility falls as more other adults have their children work. We then explore how the total amount of child labor in an economy changes as adults’ labor efficiencies rise or become more unequal. Our analysis reveals that a more equal distribution or rises in adults’ labor efficiency help decrease child labor only under certain conditions. 相似文献
8.
This study proposes a use of Data Envelopment Analysis (DEA) to measure Returns to Scale (RTS) of US coal-fired power plants. The power plants produce not only desirable outputs (e.g., electricity) but also undesirable outputs (e.g., CO2 and NOx) as a result of their plant operations. Therefore, the proposed use of DEA also measures a new concept, or “DTS: Damages to Scale” (corresponding to RTS for undesirable outputs). Both scale measures discussed in this study are a quick-and-easy approach for assessing RTS and DTS, but not an exact method, because it does not consider a direct linkage between the two measures. This study applies the proposed approach to examine the legal validity of U.S. Clean Air Act (CAA). We find that the CAA has been legally effective and influential on the operation of coal-fired power plants in the United States because their plant operations belong to increasing RTS on a desirable output and increasing DTS on three undesirable outputs. The increasing DTS indicates a need for managerial improvement and/or engineering innovation such as advanced clean coal technology. This empirical result implies that U.S. federal and state governments need to expand the legal scope of CAA to the emission control of CO2 because the current CAA excludes the regulation on CO2 emission that is now considered as a main source of the global warming and climate change. 相似文献
9.
Masashi Murakami 《Researches on Population Ecology》1999,41(2):135-138
Manipulative field experiments were performed in a northern Japanese deciduous forest to determine the role of avian predation
in the survival of three leaf-rolling lepidopterous larvae (Homonopsis foedenratana, Archips viola, and Zeiraphera corpulentana) on Japanese lilac (Syringa reticulata) trees. When all leaf rolls on the lilacs were experimentally removed, the visitation rate of birds declined, indicating
that the leaf rolls served as a visual cue for the birds. In a second experiment in which birds were excluded from the lilac
trees, the survival of H. foedenratana larvae was improved, whereas the mortality of the other two Lepidoptera stayed the same. This is probably the result of differences
in the shape of leaf rolls; larvae of H. foedenratana alter the leaf form to a greater extent, which may facilitate the detection of the rolls by birds. The high predation rate
on the tight leaf rolls of H. foedenratana may be offset by enhanced resistance against other predators and better food quality for the enclosed larvae.
Received: January 30, 1998 / Accepted: December 2, 1998 相似文献
10.
Junko Nakanishi Yasuo Morimoto Isamu Ogura Norihiro Kobayashi Masato Naya Makoto Ema Shigehisa Endoh Manabu Shimada Akira Ogami Toshihiko Myojyo Takako Oyabu Masashi Gamo Atsuo Kishimoto Takuya Igarashi Sosuke Hanai 《Risk analysis》2015,35(10):1940-1956
This study assessed the health risks via inhalation and derived the occupational exposure limit (OEL) for the carbon nanotube (CNT) group rather than individual CNT material. We devised two methods: the integration of the intratracheal instillation (IT) data with the inhalation (IH) data, and the “biaxial approach.” A four‐week IH test and IT test were performed in rats exposed to representative materials to obtain the no observed adverse effect level, based on which the OEL was derived. We used the biaxial approach to conduct a relative toxicity assessment of six types of CNTs. An OEL of 0.03 mg/m3 was selected as the criterion for the CNT group. We proposed that the OEL be limited to 15 years. We adopted adaptive management, in which the values are reviewed whenever new data are obtained. The toxicity level was found to be correlated with the Brunauer‐Emmett‐Teller (BET)‐specific surface area (BET‐SSA) of CNT, suggesting the BET‐SSA to have potential for use in toxicity estimation. We used the published exposure data and measurement results of dustiness tests to compute the risk in relation to particle size at the workplace and showed that controlling micron‐sized respirable particles was of utmost importance. Our genotoxicity studies indicated that CNT did not directly interact with genetic materials. They supported the concept that, even if CNT is genotoxic, it is secondary genotoxicity mediated via a pathway of genotoxic damage resulting from oxidative DNA attack by free radicals generated during CNT‐elicited inflammation. Secondary genotoxicity appears to involve a threshold. 相似文献