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101.
Dimitris N. Trakas Mathaios Panteli Nikos D. Hatziargyriou Pierluigi Mancarella 《Risk analysis》2019,39(1):195-211
The increased frequency of extreme events in recent years highlights the emerging need for the development of methods that could contribute to the mitigation of the impact of such events on critical infrastructures, as well as boost their resilience against them. This article proposes an online spatial risk analysis capable of providing an indication of the evolving risk of power systems regions subject to extreme events. A Severity Risk Index (SRI) with the support of real‐time monitoring assesses the impact of the extreme events on the power system resilience, with application to the effect of windstorms on transmission networks. The index considers the spatial and temporal evolution of the extreme event, system operating conditions, and the degraded system performance during the event. SRI is based on probabilistic risk by condensing the probability and impact of possible failure scenarios while the event is spatially moving across a power system. Due to the large number of possible failures during an extreme event, a scenario generation and reduction algorithm is applied in order to reduce the computation time. SRI provides the operator with a probabilistic assessment that could lead to effective resilience‐based decisions for risk mitigation. The IEEE 24‐bus Reliability Test System has been used to demonstrate the effectiveness of the proposed online risk analysis, which was embedded in a sequential Monte Carlo simulation for capturing the spatiotemporal effects of extreme events and evaluating the effectiveness of the proposed method. 相似文献
102.
Lee Crawfurd Phil Elks 《Development policy review : the journal of the Overseas Development Institute》2019,37(4):470-485
Value‐added models (VAMS) are commonly used in high‐income countries for measuring the quality of teachers and schools, on the grounds that they are a fairer reflection of true quality than simple average test scores, as they account for differences in student intake. Not accounting for student's prior test scores can give a misleading impression of school quality. In this article, we adapt the current VAM of secondary school quality to the Ugandan context, and test its robustness. Using official test score data from Uganda, we test the robustness of the model to a range of different empirical specifications, including sensitivity to the inclusion of controls for student socioeconomic status. We find that the model is robust to a variety of different specifications and control variables. The VAM is low cost and has the potential to provide a clearer signal to parents, teachers, schools, and policy‐makers about how much learning is actually happening in different schools. This approach could be carried out at low cost in a wide range of low‐income countries that have similar testing regimes. 相似文献
103.
The study surveyed 506 employees in the United States to test the effect of internal communication (i.e., corporate-level symmetrical and leadership-level responsive communications) on fostering a positive emotional culture characterized by companionate love, joy, pride, and gratitude. In addition, we tested the interplay between corporate internal communication and a positive emotional culture and its influence on supportive employee behaviors, specifically, organizational citizenship behavior (OCB) and employee advocacy. Results indicated that symmetrical communication and responsive leadership communication cultivated a positive emotional culture in organizations. Such culture also fostered employee OCB and advocacy. Moreover, corporate symmetrical communication directly and positively influenced employee OCB. Finally, this study found that employee OCB positively affected employee advocacy. The theoretical and practical implications of the findings for public relations scholars and practitioners were discussed. 相似文献
104.
Antonie Dvorakova 《The Social Science Journal》2018,55(3):346-358
This article discusses the socio-cultural dynamics that interact with ethno-racial identity experiencing in a previously under-researched group. A qualitative interdisciplinary study with 40 Native American academics from 28 mainstream universities across the U.S. served as a case example with findings that contrasted with historically influential theoretical frameworks postulating identity confusion and conflicts at the intersection of one’s mainstream education and profession versus one’s ethno-racial community grounding. Instead of feeling pressure to identify with only one worldview, the contextual, dynamic identities associated with the inclusive and flexible self-concept of tribal participants allowed them to in turn take advantage of two divergent cultural meaning systems pertaining to their distinct socio-cultural contexts. These shifts were experienced as not endogenous but rather exogenous variables, which did not cause the historically theorized issues. Participants felt their tribal identities instead facilitated meaningful integration of the existing incongruences, which resulted in unexpectedly resilient subjective experiencing. 相似文献
105.
Cynthia Akwei 《生产规划与管理》2018,29(15):1275-1289
AbstractRisk and performance management are at the core of complex bespoke systems (CBSs). CBSs are developed to customer–specified requirements in terms of structure, functionality and conformance. This article examines how risk and performance management are integrated as essential systems in the successful development of projects across multi-organizational functions in complex bespoke system (CBS) organizations. The article argues for the development of a quality management system that consists of two sub-processes: quality control and quality development. Using three case studies from engineering companies, we provide evidence and insights of the way change control, quality development and quality performance are developed in innovating business solutions. 相似文献
106.
用能方对节能服务公司(Energy Service Company,ESCO)的选择关系到合同能源管理(Energy Performance Contracting,EPC)能否顺利实施。从用能方的角度,采用灰色系统理论中的多目标加权灰靶决策模型,对存在多决策目标的ESCO选择问题进行研究。通过层次分析法确定ESCO的11个决策目标的决策权数,根据综合效果测度值的比较,最终实现最优对策的选择。本文为用能方的ESCO选择问题提供了一种新的思路。 相似文献
107.
108.
郎慧慧 《重庆邮电大学学报(社会科学版)》2018,30(6):16-22
理顺习近平关于“中国特色社会主义进入新时代”的逻辑理路,有助于系统论证“新时代”的科学性和理论性。从方法论上看,习近平新时代观是应用马克思主义立场观点和方法得出的正确结论。从理论归因看,中国社会主要矛盾的转化作为习近平新时代观生成的主要标志,源于马克思主义关于矛盾运动的基本理论。从理论定位看,习近平新时代观展现的是中国发展的特殊阶段,内含着中国对自身发展的时代定位与目标趋向,渗透着中国与世界在共同发展中的新阶段、新高度、新未来,是对中国发展方向的顶层设计。 相似文献
109.
信用评级是衡量债务违约的可能性,因此评级体系要有违约风险识别能力,能够将违约客户和非违约客户显著地区分开.通过逼近理想点的思路,构建多目标规划模型求解最优的组合权重,并对中国某区域性商业银行1 814笔小型工业企业贷款进行实证分析.本文的创新与特色一是以非违约企业的数据到正理想点的距离代数和最小为第一个目标函数,以违约企业的数据到负理想点的距离代数和最小为第二个目标函数,构建多目标非线性规划模型进行组合赋权,在满足了“非违约企业的评价得分越高、违约企业的评价得分越低”要求的目标下得到最优的组合赋权的权重系数,使赋权结果保证了评级模型能够将违约企业与非违约企业最大地区分开.改变了现有研究的组合赋权脱离评价目的的弊端,改变了现有研究中违约与非违约企业的评价得分存在大量重叠、对两类企业的区分能力低的弊端.二是通过检验“违约企业的信用得分是否显著小于非违约企业的信用得分”的J-T非参数检验,验证信用评价模型的合理性.改变现有研究忽略对信用评价模型的合理性进行验证的弊端.三是经过实证,发现本研究建立的组合赋权模型的违约鉴别能力(Z=5.546)要高于现有研究的两种常用组合赋权模型、即基于方差最大的组合赋权(Z=4.298)和基于偏差最小的组合赋权(Z=5.182) 相似文献
110.
《Social Policy & Administration》2018,52(3):790-808
When developing Community Mental Health Services to support people with psychiatric disabilities, European countries are advocating evidence ‐based practice (EBP ). Individual Placement and Support (IPS ) is an evidence ‐based model designed to support people in acquiring and maintaining competitive employment. Implementation science is a growing research field, with a focus on components that impact the process of implementing EBP programmes. In this multiple case study, we have followed three IPS demonstration sites for two years, in order to describe and analyze barriers and facilitators for implementation, according to constructs described in the Consolidated Framework for Implementation Research (Damschroder et al. 2009 ). The results highlight the importance of strategic networking, as well as the need for planning and preparations carried out before the start of an EBP programme, since deficiencies related to these constructs are difficult to compensate for. 相似文献