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171.
The performances of urban growth management are often criticized because their original objectives are frequently inconsistent with local development facts. Underlying the many reasons for this are the political and institutional contexts that influence policy-making and development activities. The urban fringe, a zone is managed to against urban sprawl in many countries, represents the conflicts between urban management system and local development resulting from political transformation. This study examines the case of decentralised-concentration strategy, one of the most important metropolitan growth management in Beijing since the 1990s, and sheds some lights on the performance of the growth management in the transformation context. The results suggest that the aims of municipal growth management to concentrate developments in urban fringe have partly been achieved through actual local developments; however, some unexpected and illegal local developments outside the planned areas are counterproductive from the perspective of municipal growth management. The performance of the present growth management is being challenged by new trends towards political decentralisation and locally fiscal responsibilities. In the interest of future policymaking, the dominant central planning system in Beijing should take these decentralisation trends into growth management account, compared with the great progress in decentralisation in economy system. The urban policy needs to shift from the dictatorial manner and put more efforts into creating a harmonious relationship between municipal growth management and actual local demands on development.  相似文献   
172.
科技查新工作既是一项高层次的综合性情报服务工作,又是科研管理工作科学化、规范化的重要环节。查新质量的高低直接影响到对科研成果的评价。分析了"全评价"体系应用于科技查新质量的可能性,研究了科技查新质量的评价主体、评价客体、评价目的、评价标准、评价指标、评价方法和评价制度,并尝试构建科技查新质量形式评价、内容评价和效用评价的指标体系,以期为科技查新质量建立一个科学的全评价体系,促进科技查新工作质量的提高。  相似文献   
173.
174.
This paper treats the problem of stochastic comparisons for the extreme order statistics arising from heterogeneous beta distributions. Some sufficient conditions involved in majorization-type partial orders are provided for comparing the extreme order statistics in the sense of various magnitude orderings including the likelihood ratio order, the reversed hazard rate order, the usual stochastic order, and the usual multivariate stochastic order. The results established here strengthen and extend those including Kochar and Xu (2007 Kochar, S.C., Xu, M. (2007). Stochastic comparisons of parallel systems when components have proportional hazard rates. Probab. Eng. Inf. Sci. 21:597609.[Crossref], [Web of Science ®] [Google Scholar]), Mao and Hu (2010 Mao, T., Hu, T. (2010). Equivalent characterizations on orderings of order statistics and sample ranges. Probab. Eng. Inf. Sci. 24:245262.[Crossref], [Web of Science ®] [Google Scholar]), Balakrishnan et al. (2014 Balakrishnan, N., Barmalzan, G., Haidari, A. (2014). On usual multivariate stochastic ordering of order statistics from heterogeneous beta variables. J. Multivariate Anal. 127:147150.[Crossref], [Web of Science ®] [Google Scholar]), and Torrado (2015 Torrado, N. (2015). On magnitude orderings between smallest order statistics from heterogeneous beta distributions. J. Math. Anal. Appl. 426:824838.[Crossref], [Web of Science ®] [Google Scholar]). A real application in system assembly and some numerical examples are also presented to illustrate the theoretical results.  相似文献   
175.
This article addresses the issue of policy change and its consequences on the organizational field and institutional context, looking at the role of an instrument transfer process. We adopt a political sociology approach to policy instruments to account for the impact that the introduction of a securitarian instrument, the mayoral order, had on the implementation process of a social policy. Through a genealogy of the instrument we identify a constitutive, normative and cognitive dimension. Our aim is to explain the interaction between these institutional dimensions, the re‐definition of the organizational field of the policy, and the dynamics of metropolitan politics. Following a synthesis of the policy process and the institutional arrangements where the policy is implemented, we show how the instrument transfer triggered a division within the organizational field, and the rise of institutional tensions amongst local authorities. In the conclusion, we identify the institutional dimensions of the instruments and the policy implementation scale as elements that are to interact with public‐private relationships and institutional arrangements, and that have an impact on implementation process and policy outcome.  相似文献   
176.
Copulas have proved to be very successful tools for the flexible modeling of dependence. Bivariate copulas have been deeply researched in recent years, while building higher-dimensional copulas is still recognized to be a difficult task. In this paper, we study the higher-dimensional dependent reliability systems using a type of decomposition called “vine,” by which a multivariate distribution can be decomposed into a cascade of bivariate copulas. Some equations of system reliability for parallel, series, and k-out-of-n systems are obtained and then decomposed based on C-vine and D-vine copulas. Finally, a shutdown system is considered to illustrate the results obtained in the paper.  相似文献   
177.
While researchers have found that African American youth experience higher levels of juvenile justice involvement at every system level (arrest, sentencing, and incarceration) relative to their other ethnic counterparts, few studies have explored how juvenile justice involvement and number of contacts might be correlated with this broad range of problems. A convenience sample of 638 African American adolescents living in predominantly low-income, urban communities participated in a survey related to juvenile justice involvement. Major findings using logistic regression models indicated that adolescents who reported juvenile justice system involvement versus no involvement were 2.3 times as likely to report mental health problems, substance abuse, and delinquent or youth offending behaviors. Additional findings documented that the higher the number of juvenile justice system contacts, the higher the rates of delinquent behaviors, alcohol and marijuana use, sex while high on drugs, and commercial sex. These findings suggest that identifying and targeting youth who have multiple juvenile justice system contacts, especially those in low-resourced communities for early intervention services, may be beneficial. Future research should examine whether peer network norms might mediate the relationships between juvenile justice involvement and youth problem behaviors.  相似文献   
178.
It is impossible to imagine the contemporary Internet without social media. Government agents, commercial, state, and social organizations, the opposition, and other citizens use social media as a giant turbine. Unfortunately, this turbine can also be used to spread disinformation as well as hostile propaganda on a mass scale. In this article we show how vulnerable social media are to infiltration by botnets with the goal of launching information attacks.  相似文献   
179.
Point and interval estimators for the scale parameter of the component lifetime distribution of a k-component parallel system are obtained when the component lifetimes are assumed to be independently and identically exponentially distributed. We prove that the maximum likelihood estimator of the scale parameter based on progressively Type-II censored system lifetimes is unique and can be obtained by a fixed-point iteration procedure. In particular, we illustrate that the Newton–Raphson method does not converge for any initial value. Furthermore, exact confidence intervals are constructed by a transformation using normalized spacings and other component lifetime distributions including Weibull distribution are discussed.  相似文献   
180.
ABSTRACT

In 2013, after nearly two decades of operating in a distributed legacy Integrated Library System (ILS) environment on local servers, the Orbis Cascade Alliance, a consortium of public and private academic libraries in Washington, Oregon, and Idaho, began a two-year-long process to migrate its 37 members to a shared implementation of Ex Libris's cloud-based Alma library management system (LMS) and Primo discovery interface. Although much has been written on electronic resource management (ERM) functionality at an institution level, little has been written on serials and ERM functionality and workflows within a shared consortial environment. This article discusses the challenges and opportunities of implementing a consortial-based LMS, with particular emphasis on serials and ERM functionality. Key migration issues related to serials control, acquisitions, licensing, administration, cataloging, statistics, and interoperability are examined at the institutional and large-scale networked levels. Benefits and limitations of using a shared consortial cloud-based LMS are explored, and the overall capabilities of the Alma LMS for electronic resource management are reviewed.  相似文献   
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