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11.
Urban Ecosystems - The urban landscape constitutes a key aspect of human - nature interactions, as more than 60% of the world’s population resides in cities and their suburbs. This study...  相似文献   
12.
Urban Ecosystems - Urban streams provide important ecosystem services to cities’ population, from the maintenance of urban biodiversity, temperature, humidity and air quality to improving...  相似文献   
13.
Urban Ecosystems - It is generally thought that increased human activity or infrastructure automatically translates to decreased wildlife activity or abundance. We surveyed dragonflies and...  相似文献   
14.
Urban Ecosystems - Although amphibians use human-created habitats in urban landscapes, few studies have investigated the quality of these habitats. To assess habitat quality of stormwater...  相似文献   
15.
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.  相似文献   
16.
Contrary to the general belief, systemic risk does not only regard the risk posed by balance sheet relationships and interdependencies among institutions. It also features a temporal dimension related to the inappropriate responses of financial market participants to changes in risk over time. This paper proposes a method to simultaneously address the cross-sectional and the time dimension in which systemic risk materializes. The method is based on the TOPHITS algorithm. It provides three scores, namely borrowing, lending and time scores: the first two represent the systemic importance of the borrowing and the lending activity associated with each financial institution,while the third represents an empirical Early Warning Signal of the financial crisis. Our findings reveal that the identification of the time score as an indicator for an incoming market distress could be relevant to design macro prudential policies.  相似文献   
17.
This study revisits the traditional single stage, multi-item, capacitated lot-sizing problem (CLSP) with a new integrative focus on problem structuring. Unlike past research, we develop integrative cycle scheduling approaches which simultaneously address lot-sizing, capacity, and sequencing issues. Our purposes are to (1) explore the effect of sequencing on inventory levels, (2) examine the problem of infeasibility in the economic lot scheduling problem (ELSP), and (3) provide a simple methodology of generating low-cost cycle schedules in an environment with discrete shipping, dynamic demands, limited capacity, zero setup cost, and sequence-independent setup times. Our procedures are compared to benchmark cycle scheduling approaches in terms of both inventory cost and computation time under different demand scenarios, using the operating data from a flexible assembly system (FAS) at the Ford Motor Company's Sandusky, Ohio plant.  相似文献   
18.
In this paper, the kernel density estimator for negatively superadditive dependent random variables is studied. The exponential inequalities and the exponential rate for the kernel estimator of density function with a uniform version, over compact sets are investigated. Also, the optimal bandwidth rate of the estimator is obtained using mean integrated squared error. The results are generalized and used to improve the ones obtained for the case of associated sequences. As an application, FGM sequences that fulfil our assumptions are investigated. Also, the convergence rate of the kernel density estimator is illustrated via a simulation study. Moreover, a real data analysis is presented.  相似文献   
19.
In this article, we introduce tempered Mittag-Leffler Lévy processes (TMLLP). TMLLP is represented as tempered stable subordinator delayed by a gamma process. Its probability density function and Lévy density are obtained in terms of infinite series and Mittag-Leffler function, respectively. Asymptotic forms of the tails and moments are given. A step-by-step procedure of the parameters estimation and simulation of sample paths is given. We also provide main results available for Mittag-Leffler Lévy processes (MLLP) and some extensions which are not available in a collective way in a single article. Our results generalize and complement the results available on Mittag-Leffler distribution and MLLP in several directions. Further, the asymptotic forms of the moments of the first-exit times of the TMLLP are also discussed.  相似文献   
20.
In this paper, a comparison between the life distribution of a new unit with that of a used unit in the increasing convex order is made leading to a new class of life distributions which we call “new better than used in convex ordering of second order”. This class includes as subclasses the NBU and the NBUC and is a subclass of the NBUCA class. Preservation properties under convolution, random maxima, mixing and formation of coherent structures are established. Stochastic comparisons of the excess lifetime when the inter-arrival times belong to the NBUC(2) class are developed. Some applications of Poisson shock models and a test of exponentiality against NBUC(2) alternative are presented.  相似文献   
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