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271.
Urbanization poses threats to earth’s biota, and retention of remnant native habitat in protected areas within expanding urban boundaries may help alleviate threats to wildlife. However, it is unclear for nearly all nonsynanthropic (i.e., not benefiting from an association with humans) species whether vital rates in urban habitats can sustain populations or if populations persist only through immigration from outside the urban boundary. We conducted a three-year study of spotted towhees (Aves: Pipilo maculatus) breeding in four undeveloped parks in Portland, OR, USA, to measure park-specific seasonal reproductive output (F) and annual adult survival (SA). We developed a stochastic model that combined F and SA with an estimate of first-year survival to measure population growth rate (λ) in all parks assumed to be closed to immigration. F differed among parks but SA did not. Relatively high F was possible because many pairs raised >1 brood/season. When combined with empirical estimates of survival through the 30-day period of post-fledging parental care (SD = 0.645), only 2 of 4 parks were self-sustaining (i.e., λ > 1.0). However, SD reflected substantial loss of fledglings to domestic cats (Felis catus). Assuming no loss to cats and either partial compensatory or additive mortality of fledglings substantially improved prospects of population persistence for declining (sink) populations. Moreover, allowing low levels of immigration to sinks reversed population declines in most parks even when vital rates were insufficient to maintain populations. Our results suggest that nonsynanthropic bird species can persist in urban landscapes, but also that offspring mortality in the post-fledging period may be a critical determinant of population viability.  相似文献   
272.
ABSTRACT

Female incarceration rates are increasing at unprecedented rates. The majority of women are poor single mothers, serving sentences for nonviolent drug-related and property offenses. Among challenges faced when transitioning back into society are a history of interpersonal violence and financial instability. This study examines literature with regard to the barriers women experience with an emphasis on financial struggles and explores outcomes of one initiative to begin addressing the financial capability of women in a minimum security prison. Findings reveal women benefited from the class experience. Social workers are called upon for additional financial capability programming and research in this area.  相似文献   
273.
Computer-assisted qualitative data analysis software (CAQDAS) programs are established tools for qualitative research. Making informed decisions when using them requires researchers to understand how they affect research practices and outcomes. In this article we consider the impact of CAQDAS on researcher reflexivity. Reviewing three decades of literature, we identify specific ‘reflexive moments’ experienced by CAQDAS users, the contexts in which they occur, the issues they raise, and the reflexive awareness they generate. The ways in which CAQDAS can enhance or undermine researcher reflexivity are also reported. By doing so, we aim to help researchers and especially research students (and their supervisors) understand the relationship between CAQDAS and reflexivity and the reflexive moments they may encounter when using such software.  相似文献   
274.
Abstract

In the past decade, security has emerged as a new discourse in water governance beyond transboundary conflicts and cooperation. This paper will examine how security is framed in the context of international river basin organizations (RBOs), key regional organizations in transboundary water governance operating in many international river basins around the world. As an example of cross-border governance, RBOs can promote joint cooperation and information sharing, and serve as a form to bring together diverse stakeholders. This paper focuses on the discursive construction of ‘security’ in a particular context of cross-border river basin governance in the Mekong River Basin. We ask: How is security framed in the discourse of RBOs? We examine how diverse actors frame security in the context of RBOs and at various scales and around certain management actions in a case study of the Mekong River Commission, a well-established RBO. Attention will be paid to the links between water security, food security, and energy security in the broader water and development discourse. We analyze what the findings mean for cross-border governance more broadly.  相似文献   
275.
This article discusses the construction of Dayak identity in the context of a violent conflict between local indigenous Dayaks and migrant Madurese in West Kalimantan province between late 1996 and early 1997. The conflict was widely regarded as an ‘ethnic’ conflict and, especially for the Dayaks who were involved in the violence, the idea of a fixed, Borneo-wide, (pan-)Dayak identity versus a common Madurese enemy was crucial. This notion of a unified, homogenous Dayak category was invoked notwithstanding the fact that Dayak groups differ greatly in many respects and that ‘Dayak’ ethnic identity is highly dynamic and fluid. This paper discusses the ways in which Kanayatn Dayaks perceived and invoked their ethnic identity during the conflict and how they later interpreted the events with a particular focus on ‘Dayakness’.  相似文献   
276.
In this article, we define the concept of “risk work,” which aims to make visible working practices to assess or manage risk, in order to subject these practices to sociological critique. This article reviews and synthesizes existing published literature to identify components of risk work: (a) translating risk into different contexts, (b) minimizing risks in practice, and (c) caring in the context of risk. We argue that these three components of risk work raise important tensions for workers that have been inadequately explored in the literature to date. We propose that future research should additionally focus on practitioner subjectivity and identity in risk work. In addition, we argue that comparative research—across type of risk and different contexts—and methodological and theoretical diversity would enhance this emerging field of research.  相似文献   
277.
We investigate the performance of capacity-sensitive order review and release (ORR) procedures in job shop environments that have not been previously explored. Previous research has ignored the case of job shops which must perform to very tight due-dates because of time-sensitive customers. We propose and test a new capacity sensitive ORR procedure called path based bottleneck (PBB) in such environments, along with the modified infinite loading (MIL) procedure which has been shown to work well in several studies. We compare the performance of these two controlled release rules with that of immediate release rule under different conditions of capacity utilization and customer specified exogenous duedates. Our results indicate that PBB performs well in lowering total costs when due-dates are tight, while MIL is a better procedure with relatively loose to medium due-dates. We also show that in many cases, the shortest processing time (SPT) dispatching rule is a superior performer than a due-date based rule like critical ratio (CR); a conclusion which is contrary to the existing research in this area. In addition, the shop floor control policies recommended are shown to be sensitive to the cost structure of the firm. The managerial implications of this research in providing effective shop floor control in job shops operating under tight due-date conditions are also discussed.  相似文献   
278.
Cellular manufacturing systems have been proposed as an alternative to the job shop since they provide some of the operational benefits of a flow line production process, while retaining to some extent the flexibility of job shops. However, this must be balanced against the possibility of additional initial investments in equipment to form the cells and a certain loss in manufacturing flexibility, particularly in terms of the ability to deal with long-term demand changes. This paper presents a model-based heuristic cell system redesign methodology to deal with such demand changes. The methodology is validated and applied to system designs generated from several data sets published in the literature. Results show that different kinds of demand changes incur distinct kinds of costs. Further, characteristics of cell designs that can handle long-term demand changes at least cost are identified.  相似文献   
279.
This study investigates the impact of worker learning, worker flexibility, and labor attrition on the system performance of a dual resource constrained (DRC) job-shop. The effects of learning and labor attrition have not been previously addressed in DRC literature. Results from the study, consistent with previous literature, show that the greatest benefits are achieved when inter-departmental worker flexibility is incrementally introduced into the system. In addition, the learning environment, which depends on the initial processing time of jobs and the learning rates of workers, is shown to impact the acquisition of flexibility. The study also shows that the impact of labor attrition on system performance under certain shop conditions may be significant.  相似文献   
280.
Since Skinner's [40] landmark article depicting the manufacturing function as the “missing link” in corporate strategic processes, a portion of the blame for inferior performance in many firms has been attributed to the subordinate strategic position of manufacturing. It has been argued that part of the solution to misalignments between the capabilities possessed by manufacturing and the requirements dictated by customers is for manufacturing to take a more proactive stance. However, little research has been reported which examines manufacturing proactiveness empirically. In this paper, we address this gap by developing an operational definition of manufacturing proactiveness and testing empirically whether a link exists between proactiveness and performance based on data collected from a sample of manufacturers. Based on the manufacturing strategy literature, we identify two major dimensions of manufacturing proactiveness: (1) the degree of manufacturing's involvement in the strategic processes of the business unit; and (2) the degree of commitment to a long-term program of investments in manufacturing structure and infrastructure aimed at building capabilities in anticipation of their need. We develop reliable scales for measuring each of the dimensions of proactiveness and use the data to provide evidence of a clear link between manufacturing proactiveness and business performance. We show that investments in structural programs coupled with either high levels of manufacturing involvement in strategic processes or planned investments in infrastructural programs correlate with higher than average performance.  相似文献   
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