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901.
Deliberations are underway to utilize increasingly radical technological options to help address climate change and stabilize the climatic system. Collectively, these options are often referred to as “climate geoengineering.” Deployment of such options, however, can create wicked tradeoffs in governance and require adaptive forms of risk management. In this study, we utilize a large and novel set of qualitative expert interview data to more deeply and systematically explore the types of risk–risk tradeoffs that may emerge from the use of 20 different climate geoengineering options, 10 that focus on carbon dioxide or greenhouse gas removal, and 10 that focus on solar radiation management and reflecting sunlight. We specifically consider: What risks does the deployment of these options entail? What types of tradeoffs may emerge through their deployment? We apply a framework that clusters risk–risk tradeoffs into institutional and governance, technological and environmental, and behavioral and temporal dimensions. In doing so, we offer a more complete inventory of risk–risk tradeoffs than those currently available within the respective risk-assessment, energy-systems, and climate-change literatures, and we also point the way toward future research gaps concerning policy, deployment, and risk management. 相似文献
902.
Heitor Oliveira Duarte Paulo Gabriel Siqueira Alexandre Calumbi Antunes Oliveira Márcio das Chagas Moura 《Risk analysis》2023,43(1):183-201
This study has developed a probabilistic epidemiological model a few weeks after the World Health Organization declared COVID-19 a pandemic (based on the little data available at that time). The aim was to assess relative risks for future scenarios and evaluate the effectiveness of different management actions for 1 year ahead. We quantified, categorized, and ranked the risks for scenarios such as business as usual, and moderate and strong mitigation. We estimated that, in the absence of interventions, COVID-19 would have a 100% risk of explosion (i.e., more than 25% infections in the world population) and 34% (2.6 billion) of the world population would have been infected until the end of simulation. We analyzed the suitability of model scenarios by comparing actual values against estimated values for the first 6 weeks of the simulation period. The results proved to be more suitable with a business-as-usual scenario in Asia and moderate mitigation in the other continents. If everything went on like this, we would have 55% risk of explosion and 22% (1.7 billion) of the world population would have been infected. Strong mitigation actions in all continents could reduce these numbers to, 7% and 3% (223 million), respectively. Although the results were based on the data available in March 2020, both the model and probabilistic approach proved to be practicable and could be a basis for risk assessment in future pandemic episodes with unknown virus, especially in the early stages, when data and literature are scarce. 相似文献
903.
The wireless network jamming problem 总被引:1,自引:0,他引:1
Clayton W. Commander Panos M. Pardalos Valeriy Ryabchenko Stan Uryasev Grigoriy Zrazhevsky 《Journal of Combinatorial Optimization》2007,14(4):481-498
In adversarial environments, disabling the communication capabilities of the enemy is a high priority. We introduce the problem
of determining the optimal number and locations for a set of jamming devices in order to neutralize a wireless communication
network. This problem is known as the wireless network jamming problem. We develop several mathematical programming formulations based on covering the communication nodes and limiting the connectivity
index of the nodes. Two case studies are presented comparing the formulations with the addition of various percentile constraints.
Finally, directions of further research are addressed. 相似文献
904.
905.
Our first goal is to link empirical measures of three theoretical explanations of marital status differences to the variation in male and female standardized suicide difference coefficients SSDCs in 12 developed countries, circa 1960. We include predictors of Durkheim's social integration hypothesis, Gibbs and Martin's concept of marital status integration, and norms on suicide acceptability. All three are significantly related to variation in male and female SSDCs. The second goal is to examine how our empirical indicators impact age-specific differences in the male minus female SSDC--differences that vary by age in all 12 of our study populations. The strongest predictor of these differences is the male minus female difference in the percent married. 相似文献
906.
Puchalski CM 《Omega》2007,56(1):33-46
Spirituality is an essential component of the care of patients with serious illness and those that are dying. Dame Cicely Saunders developed the hospice movement based on the biopsychosocialspiritual model of care, in which all four dimensions are important in the care of patients. Of all the models of care, hospice and palliative care recognize the importance of spiritual issues in the care of patients and their families. The National Consensus Project Guidelines for Quality Palliative Care, in the United States, provides specific recommendations about all domains of care including the spiritual domain, which is recognized as a critical component of care (The National Consensus Project for Quality Palliative Care www.nationalconsensusproject.org). Studies indicate that the majority of patients would like their spiritual issues addressed, yet find that their spiritual needs are not being met by the current system of care. Interestingly, spirituality is the one dimension that seems to get slightly less emphasis than the biopsychosocial dimensions of care. Some reasons may include the difficulty with definitions of spirituality for clinical and research purposes, the time constraints and financial burdens in the current healthcare system in the United States, and the lack of uniform training for all healthcare professionals. Yet, there are theoretical and ethical frameworks that support spiritual care as well as some educational models in spirituality and health that have been successful in medical education in the United States. Spirituality can be seen as the essential part of the humanity of all people. It is at its root, relational and thus forms the basis of the altruistic care healthcare professionals are committed to. Spirituality has to do with respecting the inherent value and dignity of all persons, regardless of their health status. It is the part of humans that seeks healing, particularly in the midst of suffering. Spiritual care models are based on an intrinsic aspect that calls for compassionate presence to patients as well as an extrinsic component where healthcare professionals address spiritual issues with patients and their loved ones. Currently in the healthcare system, evidence-base models are the criteria for practice recommendations. Yet, spirituality may not be amenable entirely to strict evidence-base criteria. As hospice and palliative care continues to develop as a field, healthcare professionals are challenged to think of ways to advocate for and include the spiritual dimension of care. 相似文献
907.
The present study examined the relationship between idiocentrism, allocentrism, psychological well being (self-esteem, depression, and social support), and suicidal ideation among 283 American college students and 343 Chinese college students. Idiocentrism was correlated with high self-esteem, high depression, and low social support, but the relationships were more likely to be significant for women than for men in both cultures. Allocentrism was primarily related to social support. As predicted, high levels of suicidal ideation were correlated with more idiocentrism, but only for women. Allocentrism was related to lower levels of suicidal ideation in both cultures, but the relationship was small. As suicide prevention may start from suicidal ideation treatment, the treatment of suicidal ideation may have to take into account cultural and personal characteristics, such as idiocentrism. 相似文献
908.
The aim of this work is to be a useful instrument for helping finance practitioners on the selection of suitable mutual fund portfolios. The portfolio selection problem is characterized by imprecision and/or vagueness inherent in the required data and more generally, in the context where investors have to make decisions. In order to mitigate these problems, a three stage model has been proposed based on a multi-index model and considering several market scenarios described in an imprecise way by an expert. The proposed fuzzy model allows the Decision Maker to select, by means of an outranking method, a suitable portfolio taking into account the uncertainty related to the market scenarios and the imprecision and/or vagueness associated with the model data. 相似文献
909.
910.
Surya D. Pathak Jamison M. Day Anand Nair William J. Sawaya M. Murat Kristal 《决策科学》2007,38(4):547-580
Supply networks are composed of large numbers of firms from multiple interrelated industries. Such networks are subject to shifting strategies and objectives within a dynamic environment. In recent years, when faced with a dynamic environment, several disciplines have adopted the Complex Adaptive System (CAS) perspective to gain insights into important issues within their domains of study. Research investigations in the field of supply networks have also begun examining the merits of complexity theory and the CAS perspective. In this article, we bring the applicability of complexity theory and CAS into sharper focus, highlighting its potential for integrating existing supply chain management (SCM) research into a structured body of knowledge while also providing a framework for generating, validating, and refining new theories relevant to real‐world supply networks. We suggest several potential research questions to emphasize how a CAS perspective can help in enriching the SCM discipline. We propose that the SCM research community adopt such a dynamic and systems‐level orientation that brings to the fore the adaptivity of firms and the complexity of their interrelations that are often inherent in supply networks. 相似文献