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Integrating Operational and Organizational Aspects in Interdependent Infrastructure Network Recovery
Camilo Gomez Andrs D. Gonzlez Hiba Baroud Claudia D. Bedoya‐Motta 《Risk analysis》2019,39(9):1913-1929
Managing risk in infrastructure systems implies dealing with interdependent physical networks and their relationships with the natural and societal contexts. Computational tools are often used to support operational decisions aimed at improving resilience, whereas economics‐related tools tend to be used to address broader societal and policy issues in infrastructure management. We propose an optimization‐based framework for infrastructure resilience analysis that incorporates organizational and socioeconomic aspects into operational problems, allowing to understand relationships between decisions at the policy level (e.g., regulation) and the technical level (e.g., optimal infrastructure restoration). We focus on three issues that arise when integrating such levels. First, optimal restoration strategies driven by financial and operational factors evolve differently compared to those driven by socioeconomic and humanitarian factors. Second, regulatory aspects have a significant impact on recovery dynamics (e.g., effective recovery is most challenging in societies with weak institutions and regulation, where individual interests may compromise societal well‐being). And third, the decision space (i.e., available actions) in postdisaster phases is strongly determined by predisaster decisions (e.g., resource allocation). The proposed optimization framework addresses these issues by using: (1) parametric analyses to test the influence of operational and socioeconomic factors on optimization outcomes, (2) regulatory constraints to model and assess the cost and benefit (for a variety of actors) of enforcing specific policy‐related conditions for the recovery process, and (3) sensitivity analyses to capture the effect of predisaster decisions on recovery. We illustrate our methodology with an example regarding the recovery of interdependent water, power, and gas networks in Shelby County, TN (USA), with exposure to natural hazards. 相似文献
3.
Rachael Piltch‐Loeb Brian J. Zikmund‐Fisher Victoria A. Shaffer Laura D. Scherer Megan Knaus Angie Fagerlin David M. Abramson Aaron M. Scherer 《Risk analysis》2019,39(12):2683-2693
Perceptions of infectious diseases are important predictors of whether people engage in disease‐specific preventive behaviors. Having accurate beliefs about a given infectious disease has been found to be a necessary condition for engaging in appropriate preventive behaviors during an infectious disease outbreak, while endorsing conspiracy beliefs can inhibit preventive behaviors. Despite their seemingly opposing natures, knowledge and conspiracy beliefs may share some of the same psychological motivations, including a relationship with perceived risk and self‐efficacy (i.e., control). The 2015–2016 Zika epidemic provided an opportunity to explore this. The current research provides some exploratory tests of this topic derived from two studies with similar measures, but different primary outcomes: one study that included knowledge of Zika as a key outcome and one that included conspiracy beliefs about Zika as a key outcome. Both studies involved cross‐sectional data collections that occurred during the same two periods of the Zika outbreak: one data collection prior to the first cases of local Zika transmission in the United States (March–May 2016) and one just after the first cases of local transmission (July–August). Using ordinal logistic and linear regression analyses of data from two time points in both studies, the authors show an increase in relationship strength between greater perceived risk and self‐efficacy with both increased knowledge and increased conspiracy beliefs after local Zika transmission in the United States. Although these results highlight that similar psychological motivations may lead to Zika knowledge and conspiracy beliefs, there was a divergence in demographic association. 相似文献
4.
Proportional hazards are a common assumption when designing confirmatory clinical trials in oncology. This assumption not only affects the analysis part but also the sample size calculation. The presence of delayed effects causes a change in the hazard ratio while the trial is ongoing since at the beginning we do not observe any difference between treatment arms, and after some unknown time point, the differences between treatment arms will start to appear. Hence, the proportional hazards assumption no longer holds, and both sample size calculation and analysis methods to be used should be reconsidered. The weighted log‐rank test allows a weighting for early, middle, and late differences through the Fleming and Harrington class of weights and is proven to be more efficient when the proportional hazards assumption does not hold. The Fleming and Harrington class of weights, along with the estimated delay, can be incorporated into the sample size calculation in order to maintain the desired power once the treatment arm differences start to appear. In this article, we explore the impact of delayed effects in group sequential and adaptive group sequential designs and make an empirical evaluation in terms of power and type‐I error rate of the of the weighted log‐rank test in a simulated scenario with fixed values of the Fleming and Harrington class of weights. We also give some practical recommendations regarding which methodology should be used in the presence of delayed effects depending on certain characteristics of the trial. 相似文献
5.
This article explores the position, potential and scope for self-employment and microenterprise for disabled South Koreans. The chronic barriers experienced in disabled people gaining paid work suggest that self-employment and enterprise might offer a good alternative to paid work. The self-determined nature of running a microenterprise has been shown to connect with disabled people who may not conform to standardised notions of body and brain that underpin many mainstream work contexts. Despite this promise, several barriers continue to beset disabled people’s access to micro-enterprise activity; barriers ranging from Confucian precepts, to employment protections that are geared largely towards paid employment and to the lack of training, finance and business support for disabled people starting up and sustaining microenterprise in Korea. The extension of legal protections, meaningful start-up subsidies, better business support and bridges between paid work and microenterprise are all seen as important policy correctives that would better support disabled people. 相似文献
6.
Adrian D. Van Breda 《Journal of youth studies》2015,18(3):322-337
The journey out of care and towards independent living is a challenge for many care-leavers. There has been little research into the social processes involved in this care-leaving journey. This paper presents the results of a grounded theory investigation into the care-leaving journeys of nine young men who had, several years previously, been in the care of Girls & Boys Town in South Africa. Working from a resilience perspective, with an ecological emphasis, four central social processes emerged that together explain the care-leaving experiences of the participants. These processes are striving for authentic belonging; networking people for goal attainment; contextualised responsiveness and building hopeful and tenacious self-confidence. These four processes are located within contextual boundaries and at the social environmental interface. The paper presents these processes in detail, drawing on selected narratives of the participants and integrated with additional theory. It is hoped that this paper may contribute to theory building concerning care-leaving processes and enhance youth care practices for youth in care and leaving care. 相似文献
7.
Alan Spector 《The American Sociologist》2002,33(4):111-126
Marxist sociology is at the intersection of Marxism and sociology; while humanist sociology is at the intersection of humanist
thought and sociology. Both see sociological theory as a living, evolving activity, and both take a critical stance toward
the workings of capitalism. The main difference between them is that Marxist sociology is a body of thought tied to a movement,
whereas humanist sociology is a movement tied to a body of thought.
Professor of Sociology, Purdue University Calumet. He is past chair of the Section on Marxist Sociology, has been a member
of the AHS for twenty years, and is co-author of Crisis and Change: Basic Questions of Marxist Sociology. 相似文献
8.
The authors maintain that the social learning theory of career development and counseling has not been applied to diverse populations. To address this gap in the literature, the authors conducted a qualitative analysis of interviews with 21 middle school students in a low‐income, culturally diverse, inner‐city public school. Four themes emerged, reflecting the influence of discrimination on participants' career learning: contextual barriers and resources for learning, and psychological barriers and resources for learning. The authors provide a conceptual framework for assessing resources and barriers and a rationale for why these aspects often remain hidden or unexamined in career assessment with clients who are vulnerable to discrimination. 相似文献
9.
10.
Alison Snow Jones 《Journal of Family and Economic Issues》2002,23(1):3-25
The association between drinking and selected job characteristics among women aged 24 to 31 is examined. Using the 1989 NLSY, women are classified as alcohol abusers or dependent based on DSM-III-R criteria or as heavy drinkers based on reported frequency of six or more drinks. Heavy drinking is negatively associated with wage and non-wage compensation. These effects diminish when human capital measures are controlled. Current alcoholism and current and past heavy drinking are strongly negatively associated with years of schooling. The association between alcoholism and job compensation and characteristics is not as strong as that seen for heavy drinking. It is not known if this is a consequence of errors in identifying alcoholic women in population-based surveys. 相似文献