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721.
This article proposes a novel mathematical optimization framework for the identification of the vulnerabilities of electric power infrastructure systems (which is a paramount example of critical infrastructure) due to natural hazards. In this framework, the potential impacts of a specific natural hazard on an infrastructure are first evaluated in terms of failure and recovery probabilities of system components. Then, these are fed into a bi‐level attacker–defender interdiction model to determine the critical components whose failures lead to the largest system functionality loss. The proposed framework bridges the gap between the difficulties of accurately predicting the hazard information in classical probability‐based analyses and the over conservatism of the pure attacker–defender interdiction models. Mathematically, the proposed model configures a bi‐level max‐min mixed integer linear programming (MILP) that is challenging to solve. For its solution, the problem is casted into an equivalent one‐level MILP that can be solved by efficient global solvers. The approach is applied to a case study concerning the vulnerability identification of the georeferenced RTS24 test system under simulated wind storms. The numerical results demonstrate the effectiveness of the proposed framework for identifying critical locations under multiple hazard events and, thus, for providing a useful tool to help decisionmakers in making more‐informed prehazard preparation decisions. 相似文献
722.
Mooly Mei‐ching Wong Joyce Lai‐Chong Ma Rhea Rui Yuan 《Asian Social Work and Policy Review》2019,13(3):242-251
This study draws on survey data from 205 family mediation service users concerning their satisfaction with the outcomes of mediation to address two research questions: (a) how satisfied are service users? and (b) what factors account for users' satisfaction with the outcome of child custody arrangements and the allocation of finances and property? Overall, users' level of satisfaction with outcomes was high. While the mediation process explained a significant variance in satisfaction with the outcomes for child custody and for finances and property, the mediator's perceived professional competence did not predict user satisfaction with the outcomes for either issue. This study contributes to our knowledge on the significance of mediators' process skill, specifically their calm and clear responses to the socioemotional needs of the mediated parties, on the service outcomes for both types of dispute. The implications for mediation training are discussed. 相似文献
723.
724.
Respect for the elderly and hence the associated rights support a generational contract. Nevertheless, the case of the recent debate on the universal retirement scheme in Hong Kong has raised concerns about its strength. We identify relevant items from the sixth wave of the World Values Survey to explore the orientations of different generations toward others. The analysis shows differences between younger and older generations. Regression analyses show that values are not significant in explaining the differences, but various positions, including sex, marital status, and education, and perceptions of the elderly are relevant. Such differences across generations might weaken the generational contract and potentially engender conflicts as shown in the recent debate about the retirement scheme. We suggest short‐ and long‐term interest calculations, informed by their positions, play a more significant role in policy discussions and decisions, rather than simply appealing to values. 相似文献
725.
Kathryn Showalter Susan Yoon Kathryn Maguire‐Jack Kathryn G. Wolf Megan Letson 《Child & Family Social Work》2020,25(2):439-447
A significant portion of children living in the United States have experienced trauma. Informed by the developmental traumatology model, we explored the effects of physical abuse and witnessing intimate partner violence (IPV) on childhood trauma symptoms. This study utilizes a convenience sample of 580 high‐risk children between 3 and 12 years who received services from one‐child advocacy centre during a 12‐month period. We performed a series of binary logistic regression analyses to examine if physical abuse, exposure to IPV, and dual exposure (i.e., both physical abuse and IPV) are distinctly associated with six trauma symptoms, including anxiety, depression, posttraumatic stress (PTS), dissociation, anger, and sexual concerns. The results indicated that dual exposure was predictive of all trauma symptoms, except for dissociation. Additionally, physical abuse was associated with PTS, anger, and sexual concerns, whereas exposure to IPV was associated with depression, PTS, and sexual concerns. Research and implications for practitioners working with young children are discussed. 相似文献
726.
Peter A. F. Fraser‐Mackenzie Tiejun Ma Ming‐Chien Sung Johnnie E. V. Johnson 《Risk analysis》2019,39(7):1560-1581
“Chasing” behavior, whereby individuals, driven by a desire to break even, continue a risky activity (RA) despite incurring large losses, is a commonly observed phenomenon. We examine whether the desire to break even plays a wider role in decisions to stop engaging in financially motivated RA in a naturalistic setting. We test hypotheses, motivated by this research question, using a large data set: 707,152 transactions of 5,379 individual financial market spread traders between September 2004 and April 2013. The results indicate strong effects of changes in wealth around the break‐even point on the decision to cease an RA. An important mediating factor was the individual's historical long‐term performance. Those with a more profitable trading history were less affected by a fall in cash balance below the break‐even point compared to those who had been less profitable. We observe that break‐even points play an important role in the decision of nonpathological risk takers to stop RAs. It is possible, therefore, that these nonpathological cognitive processes, when occurring in extrema, may result in pathological gambling behavior such as “chasing.” Our data set focuses on RAs in financial markets and, consequently, we discuss the implications for institutions and regulators in the effective management of risk taking in markets. We also suggest that there may be a need to consider carefully the nature and role of “break‐even points” associated with a broader range of nonfinancially‐focused risk‐taking activities, such as smoking and substance abuse. 相似文献
727.
This present study, using a longitudinal design, investigated how depressive symptoms are related to academic achievement and whether the perceptions of teachers’ and peers’ behaviors moderated this relation. A sample of 302 adolescents (60.10% girls, Mage = 17.35) completed scales measuring the depressive symptoms and perception of their teachers’ support/equity and peers’ cooperation/cohesiveness behaviors at Time 1. The adolescents’ average grades were also collected. The adolescents’ depressive symptoms and average grades were measured again at Time 2. The results showed that depressive symptoms measured at Time 1 were negatively associated with academic achievement measured at Time 2. The adolescents’ perception of their peers’ cooperation/cohesiveness moderated the relation between depressive symptoms and academic achievement. The results’ implications for educational practice are discussed. 相似文献
728.
Linda P. Dekker Kirsten Visser Esther J.M. van der Vegt Athanasios Maras Jan van der Ende Nouchka T. Tick Frank C. Verhulst Kirstin Greaves‐Lord 《Journal of research on adolescence》2020,30(2):487-501
The private nature of psychosexual functioning leads adolescents and their parents to have different perspectives, which highlights studying parent–child informant discrepancies in this domain. We investigated informant discrepancy in psychosexual functioning, using the self‐report and parent report versions of the Teen Transition Inventory (TTI), of adolescents with autism spectrum disorder (ASD; 136 parent–child dyads) compared to adolescents from the general population (GP; 70 parent–child dyads). Significantly larger informant discrepancies exist in ASD dyads than GP dyads in most domains of psychosexual functioning, except for Body image, Sexual behavior, and Confidence in the future. It is important to use and pay attention to both informants, as discrepancies are relevant for both research and clinical practice regarding psychosexual functioning. 相似文献
729.
730.
Katelyn K. Fletcher Carolyn Brockmeyer Cates Alan L. Mendelsohn Catherine S. Tamis‐LeMonda 《Infancy》2020,25(5):535-551
Play offers rich opportunities for toddlers to develop motor, social, cognitive, and language skills, particularly during interactions with adult caregivers who may scaffold toddlers to higher levels of play than toddlers achieve on their own. However, research on play has narrowly focused on children from White, middle‐income backgrounds, leaving a dearth of knowledge about dyadic play in diverse cultural communities. We videorecorded 222 Mexican‐American mothers playing with their 2‐year‐old toddlers with a standard set of toys. Play behaviors were coded as nonsymbolic or symbolic (play type) and as expressed through manual, verbal, or multiple channels (play modality). Play between toddlers and mothers was frequent, high in symbolic content, and toddler play closely corresponded with mother play in type and modality: Toddlers’ nonsymbolic play related to mothers’ nonsymbolic play; toddlers’ symbolic play related to mothers’ symbolic play; toddlers’ manual play related to mothers’ manual play; and toddlers’ multimodal play related to mothers’ multimodal play. Play in Mexican‐American mothers and toddlers is frequent, multimodal, and symbolically rich, offering new directions for future research and practice. 相似文献