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91.
应急救援物资车辆运输线路的选择 总被引:10,自引:0,他引:10
为了给紧急救援物资支持保障中心的物资调度人员提供科学的车辆路线调度决策方法,提高应急救援工作的响应能力,基于应急条件下物资运输调度的时效性、安全性和经济性特征,运用旅行商理论,对上述3个决策属性分量进行了数学描述,构造了它们的目标函数,并进行了无量纲和权重聚合处理,继而按照多属性决策理论建立了用来评价备选线路决策效用函数的数学模型.利用期望效用属性合并所搜集的信息,将多属性决策问题转化成单属性决策问题,确立了选择具有最高期望效用方案的方法,最后进行了实例分析.结果表明,应急救援条件下的运输调度与正常环境下的企业运输调度决策目标之间存在明显的差异,前者虽然本质上属于图论中最短路线问题的范畴,但由于多个决策目标的存在,不能直接运用最短路线模型和Dijkstra算法求解.运用多属性决策理论建立的评价备选线路决策效用函数,是有关人员进行车辆路线安排的有效方法,但其相对优越性尚需做进一步的研究和探讨. 相似文献
92.
研究松花江蓄洪区选址问题的决策方法.松花江蓄滞洪区选址问题涉及诸多定性指标和定量指标,属于半结构决策问题.本文综合层次分析法和模糊优选法,提出求解这类问题的一种半结构决策方法.基本方法是:将评价指标分为定性指标和定量指标;对于定性应用层次分析法,求其评价矩阵;对于定量指标应用相对隶属度方法,求其评价矩阵;二者合成得到全体指标的评价矩阵;最后利用模糊优选法求得最优决策.应用该方法于松花江流域蓄滞洪区的方案选择中. 相似文献
93.
基于熵权-HDT的航空器维修人误概率确定 总被引:1,自引:1,他引:0
人误是造成民用航空维修差错的主要因素。为确定不同情境下人误发生概率,结合某维修基地具体情况,采用熵权法确定主要的影响因子,并基于全决策树法分析主要影响因子对航空器维修人误概率的影响程度。计算结果显示,该维修基地人因可靠性的主要影响因子包括航空器维修人员的安全态度、技能、沟通、工作环境、压力以及工段长领导能力。根据各主要影响因子的不同品质描述等级组合,确定该情境下航空器维修人员的人误概率。鉴于该维修基地人因可靠性影响最明显的因子是"沟通",提出信息及时交流、明确沟通重要性等解决措施。 相似文献
94.
为准确评判矿山采空区稳定性等级,通过分析采空区稳定性各影响因素,确定地质、水文、采空区几何参数、环境等4个2级指标为影响其稳定性的主要因素。运用层次分析法(AHP)并结合模糊数学理论,建立采空区稳定性2级模糊综合评判模型。用区间数表示评判结果,分析处理评判矩阵得到专家评判的相似度和差异度,进而获取专家评判的可信度,建立基于不确定型层次分析法(UAHP)的采空区稳定性模糊评判方法。实例计算结果表明:在Ⅰ级评判指标中,地质构造、周围开采影响、地下水活动程度、跨度对采空区稳定性影响较大;用该采空区的稳定性等级为Ⅱ级。用该方法能得出各影响因素的综合权重,准确评判采空区稳定性等级。 相似文献
95.
为揭示并量化海运人因可靠性分析(HRA)中行为形成因子(PSF)间复杂的影响关系,采用DEMATEL方法对航海人员值班任务中9个PSF的依赖关系进行建模和分析,并验证该方法的有效性。结果表明:船上组织的完善程度、驾驶台班组成员的合作质量、可用时间等PSF在系统中的作用大;船上组织的完善程度、人机界面(MMI)与运行支持的完善性、值班区间以及培训和准备的充分性4个PSF为原因因素,驾驶台班组成员的合作质量、同时出现的目标任务数量、可用时间、船上工作及船舶航行条件和操作规程/计划的可用性5个PSF为结果因素。安全管理人员应针对作用大或原因因素中的PSF制定安全管理措施,改善情景环境,提高人因可靠性。 相似文献
96.
Joslin L. Moore Abbey E. Camaclang Alana L. Moore Cindy E. Hauser Michael C. Runge Victor Picheny Libby Rumpff 《Conservation biology》2021,35(5):1639-1649
Land managers decide how to allocate resources among multiple threats that can be addressed through multiple possible actions. Additionally, these actions vary in feasibility, effectiveness, and cost. We sought to provide a way to optimize resource allocation to address multiple threats when multiple management options are available, including mutually exclusive options. Formulating the decision as a combinatorial optimization problem, our framework takes as inputs the expected impact and cost of each threat for each action (including do nothing) and for each overall budget identifies the optimal action to take for each threat. We compared the optimal solution to an easy to calculate greedy algorithm approximation and a variety of plausible ranking schemes. We applied the framework to management of multiple introduced plant species in Australian alpine areas. We developed a model of invasion to predict the expected impact in 50 years for each species-action combination that accounted for each species’ current invasion state (absent, localized, widespread); arrival probability; spread rate; impact, if present, of each species; and management effectiveness of each species-action combination. We found that the recommended action for a threat changed with budget; there was no single optimal management action for each species; and considering more than one candidate action can substantially increase the management plan's overall efficiency. The approximate solution (solution ranked by marginal cost-effectiveness) performed well when the budget matched the cost of the prioritized actions, indicating that this approach would be effective if the budget was set as part of the prioritization process. The ranking schemes varied in performance, and achieving a close to optimal solution was not guaranteed. Global sensitivity analysis revealed a threat's expected impact and, to a lesser extent, management effectiveness were the most influential parameters, emphasizing the need to focus research and monitoring efforts on their quantification. 相似文献
97.
Human perception of risks related to economic damages caused by nearby wildlife can be transmitted through social networks. Understanding how sharing risk information within a human community alters the spatial dynamics of human-wildlife interactions has important implications for the design and implementation of effective conservation actions. We developed an agent-based model that simulates farmer livelihood decisions and activities in an agricultural landscape shared with a population of a generic wildlife species (wildlife-human interactions in shared landscapes [WHISL]). In the model, based on risk perception and economic information, farmers decide how much labor to allocate to farming and whether and where to exclude wildlife from their farms (e.g., through fencing, trenches, or vegetation thinning). In scenarios where the risk perception of farmers was strongly influenced by other farmers, exclusion of wildlife was widespread, resulting in decreased quality of wildlife habitat and frequency of wildlife damages across the landscape. When economic losses from encounters with wildlife were high, perception of risk increased and led to highly synchronous behaviors by farmers in space and time. Interactions between wildlife and farmers sometimes led to a spillover effect of wildlife damage displaced from socially and spatially connected communities to less connected neighboring farms. The WHISL model is a useful conservation-planning tool because it provides a test bed for theories and predictions about human-wildlife dynamics across a range of different agricultural landscapes. 相似文献
98.
为研究特大地震初期的高层决策行为,通过演练模拟决策者在可得灾情信息下进行决策部署的情形,采集参演决策者独立确认的最终决策文本为样本,对比分析样本对草案修改的方式和程度,将决策者分为独立型、合作型和依赖型。结构化处理提取样本的决策任务,分析与灾情信息及决策建议的相关性。结果表明:在高层决策者中合作型人数比例最高,群组内决策差异较小,质量相对稳定;独立型决策者偏好主观判断,对灾情的关注以及草案漏洞的审查等指标明显低于其他类型;依赖型决策者在使用合理化建议的前提下易做出高质量决策,但在决策支持失误而非漏洞的条件下,能否保证决策质量有待进一步验证。 相似文献
99.
Minimizing the cost of translocation failure with decision‐tree models that predict species’ behavioral response in translocation sites
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The high number of failures is one reason why translocation is often not recommended. Considering how behavior changes during translocations may improve translocation success. To derive decision‐tree models for species’ translocation, we used data on the short‐term responses of an endangered Australian skink in 5 simulated translocations with different release conditions. We used 4 different decision‐tree algorithms (decision tree, decision‐tree parallel, decision stump, and random forest) with 4 different criteria (gain ratio, information gain, gini index, and accuracy) to investigate how environmental and behavioral parameters may affect the success of a translocation. We assumed behavioral changes that increased dispersal away from a release site would reduce translocation success. The trees became more complex when we included all behavioral parameters as attributes, but these trees yielded more detailed information about why and how dispersal occurred. According to these complex trees, there were positive associations between some behavioral parameters, such as fight and dispersal, that showed there was a higher chance, for example, of dispersal among lizards that fought than among those that did not fight. Decision trees based on parameters related to release conditions were easier to understand and could be used by managers to make translocation decisions under different circumstances. Minimizar el Costo del Fracaso de la Reubicación con Modelos de Árboles de Decisión que Predigan la Respuesta Conductual de la Especie en los Sitios de Reubicación 相似文献
100.
Effective conservation policies require comprehensive knowledge of biodiversity. However, knowledge shortfalls still remain, hindering possibilities to improve decision making and built such policies. During the last 2 decades, conservationists have made great efforts to allocate resources as efficiently as possible but have rarely considered the idea that if research investments are also strategically allocated, it would likely fill knowledge gaps while simultaneously improving conservation actions. Therefore, prioritizing areas where both conservation and research actions could be conducted becomes a critical endeavor that can further maximize return on investment. We used Zonation, a conservation planning tool and geographical distributions of amphibians, birds, mammals, and reptiles to suggest and compare priority areas for conservation and research of terrestrial vertebrates worldwide. We also evaluated the degree of human disturbance in both types of priority areas by describing the value of the human footprint index within such areas. The spatial concordance between priority conservation and research areas was low: 0.36% of the world's land area. In these areas, we found it would be possible to protect almost half of the currently threatened species and to gather information on nearly 42% of data-deficient (DD) species. We also found that 6199 protected areas worldwide are located in such places, although only 35% of them have strict conservation purposes. Areas of consensus between conservation and research areas represent an opportunity for simultaneously conserving and acquiring knowledge of threatened and DD species of vertebrates. Although the picture is not the most encouraging, joint conservation and research efforts are possible and should be fostered to save vertebrate species from our own ignorance and extinction. 相似文献