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241.
Quantifying the Establishment Likelihood of Invasive Alien Species Introductions Through Ports with Application to Honeybees in Australia 下载免费PDF全文
The cost of an uncontrolled incursion of invasive alien species (IAS) arising from undetected entry through ports can be substantial, and knowledge of port‐specific risks is needed to help allocate limited surveillance resources. Quantifying the establishment likelihood of such an incursion requires quantifying the ability of a species to enter, establish, and spread. Estimation of the approach rate of IAS into ports provides a measure of likelihood of entry. Data on the approach rate of IAS are typically sparse, and the combinations of risk factors relating to country of origin and port of arrival diverse. This presents challenges to making formal statistical inference on establishment likelihood. Here we demonstrate how these challenges can be overcome with judicious use of mixed‐effects models when estimating the incursion likelihood into Australia of the European (Apis mellifera) and Asian (A. cerana) honeybees, along with the invasive parasites of biosecurity concern they host (e.g., Varroa destructor). Our results demonstrate how skewed the establishment likelihood is, with one‐tenth of the ports accounting for 80% or more of the likelihood for both species. These results have been utilized by biosecurity agencies in the allocation of resources to the surveillance of maritime ports. 相似文献
242.
Sarah Diem Anjalé D. Welton Erica Frankenberg Jennifer Jellison Holme 《Race Ethnicity and Education》2016,19(4):731-762
Suburbs across the US are experiencing dramatic demographic shifts, yet there is little research available on how suburban school districts are dealing with these changes. In this article, we examine the discourses surrounding race and demographic change in three suburban school districts that have been undergoing rapid demographic changes and which contain demographically distinct areas within their district boundaries. Utilizing a critical discourse analysis (CDA) approach, we analyze how the policy context (federal and state) frames actors’ discourses and understandings of race, paying particular attention to the political and institutional factors affecting school policy. We illustrate how the discourse, in turn, is related to the actions (or inactions) taken by district and school leaders to respond to demographic change. We conclude the article by discussing policy implications and potential challenges districts may face in the future if efforts to purposively address racial changes continue to be avoided. 相似文献
243.
《Risk analysis》2018,38(3):562-584
Currently, published risk analyses for drones refer mainly to commercial systems, use data from civil aviation, and are based on probabilistic approaches without suggesting an inclusive list of hazards and respective requirements. Within this context, this article presents: (1) a set of safety requirements generated from the application of the systems theoretic process analysis (STPA) technique on a generic small drone system; (2) a gap analysis between the set of safety requirements and the ones met by 19 popular drone models; (3) the extent of the differences between those models, their manufacturers, and the countries of origin; and (4) the association of drone prices with the extent they meet the requirements derived by STPA. The application of STPA resulted in 70 safety requirements distributed across the authority, manufacturer, end user, or drone automation levels. A gap analysis showed high dissimilarities regarding the extent to which the 19 drones meet the same safety requirements. Statistical results suggested a positive correlation between drone prices and the extent that the 19 drones studied herein met the safety requirements generated by STPA, and significant differences were identified among the manufacturers. This work complements the existing risk assessment frameworks for small drones, and contributes to the establishment of a commonly endorsed international risk analysis framework. Such a framework will support the development of a holistic and methodologically justified standardization scheme for small drone flights. 相似文献
244.
Susan Liddy 《Feminist Media Studies》2016,16(5):901-917
Despite the many social and cultural changes that have occurred in Irish society since the Irish Film Board was re-established in 1993, the Irish film industry remains strongly male dominated. Specifically, Irish women constitute a minority of produced screenwriters and writer/directors. This article contributes to an understanding of the discursive resources that key decision makers in the Irish Film Board draw upon in order to talk about gender. A number of interpretative repertoires are used to rationalize its position in relation to the dearth of women screenwriters, four of which are examined here: evasion and deflection; gender neutrality; project-led funding; and a difficulty making sense of entrenched gender issues, articulated here as “I don’t know.” Within the respondents’ repertoires an ideological dilemma can be identified in the conceptualization of gender as both relevant and irrelevant. 相似文献
245.
公路班线客运集约化改革的难点在于利益关系的协调。在广泛调研和深入访谈的基础上,结合班线客运发展历程及现状,从利益分析的视角剖析了政府、企业、个体之间的利益诉求、利益冲突及利益博弈的内在机理,指出挂靠关系下企业与个体之间的利益争夺是集约化发展难以推进的根源。研究提出以当前利益分配格局为均衡点的“实收配股”集约化发展改革方案,同时强调政府应转变职能定位、完善相关政策,防止形成市场封锁或垄断。 相似文献
246.
《Journal of Statistical Computation and Simulation》2012,82(2-3):97-107
Kleinbaum (1973) developed a generalized growth curve model for analyzing incomplete longitudinal data. In this paper the small sample properties of several related test statistics are investigated via Monte Carlo techniques. The covariance matrix is estimated by each of three non-iterative methods. The null and non-null distributions of these test statistics are examined. 相似文献
247.
本文基于面板数据的因子分析,从经济效益、科技与人才、能源与环保三个维度对西部十一省工业综合竞争力进行评估。结果表明,西部地区工业竞争力总体水平不高且不平衡明显。其中四川、重庆、陕西、广西、云南是西部具有较强的工业竞争力的地区,而贵州、甘肃、内蒙古、新疆、青海、宁夏竞争力较弱。因此要有针对性地实施发展规划,以促进西部地区工业差距缩小与总体发展水平的提升。 相似文献
248.
以FDI与我国出口贸易品技术含量的关系作为切入点,选择通信设备、计算机制造业、医药制造业作为高新技术产业的代表,通用设备制造业、专用设备制造业作为传统制造业的代表。根据这4个行业1997—2011年利用外资与出口贸易品技术含量的数据,基于面板数据模型对高新技术产业和传统制造业FDI与出口贸易品技术含量之间的长期均衡关系及相关性进行实证分析。结果表明:高新技术产业利用外资与出口贸易品技术含量存在着长期均衡稳定关系,出口贸易品技术含量随着高新技术产业利用外资的增加而提高,并有明显的促进作用,而传统制造业利用外资对出口贸易品技术含量的影响有限。 相似文献
249.
Joost R. Santos 《Risk analysis》2012,32(10):1673-1692
Disruptions in the production of commodities and services resulting from disasters influence the vital functions of infrastructure and economic sectors within a region. The interdependencies inherent among these sectors trigger the faster propagation of disaster consequences that are often associated with a wider range of inoperability and amplified losses. This article evaluates the impact of inventory‐enhanced policies for disrupted interdependent sectors to improve the disaster preparedness capability of dynamic inoperability input‐output models (DIIM). In this article, we develop the dynamic cross‐prioritization plot (DCPP)—a prioritization methodology capable of identifying and dynamically updating the critical sectors based on preference assignments to different objectives. The DCPP integrates the risk assessment metrics (e.g., economic loss and inoperability), which are independently analyzed in the DIIM. We develop a computer‐based DCPP tool to determine the priority for inventory enhancement with user preference and resource availability as new dimensions. A baseline inventory case for the state of Virginia revealed a high concentration of (i) manufacturing sectors under the inoperability objective and (ii) service sectors under the economic loss objective. Simulation of enhanced inventory policies for selected critical manufacturing sectors has reduced the recovery period by approximately four days and the expected total economic loss by $33 million. Although the article focuses on enhancing inventory levels in manufacturing sectors, complementary analysis is recommended to manage the resilience of the service sectors. The flexibility of the proposed DCPP as a decision support tool can also be extended to accommodate analysis in other regions and disaster scenarios. 相似文献
250.
Scholars utilizing situational crisis communication theory (SCCT) mainly examine how attributed responsibility affects organizational reputation and how response strategies matched with the amount of attributed responsibility protect reputation. The findings on these 2 important questions have been mixed. A meta-analysis of 35 investigations from 24 studies published between January 1990 and March 2015 was conducted to explain the mixed findings and reveal average correlations. Attributed responsibility was strongly associated with reputation at –.54, and response strategies were only weakly associated with reputation at .23. Equally important, crisis vignette choice moderated the responsibility-reputation association. Crisis clusters, reputation measurements, sample choice, and crisis vignette choice moderated the match-reputation association. Theoretical, methodological, and practical implications were discussed. 相似文献