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1.
Disaster relief involves a broad range of participants, which often results in a disjunction between actual disaster needs and the perception of appropriate strategies in relief provision. This research examines data collected through interviews with donation drive operators responding to Superstorm Sandy in 2012 and the May 2013 Oklahoma tornadoes. Using Weber's ideal types of social action to understand motivations for engaging in disaster relief, this article argues that motivations for participating in and organizing such drives influence donation strategies, and these motivations can be used to explain persistent donation of nonuseful materiel items. Findings indicate several different motivations for involvement and that donation type appeared linked to motivation. We suggest that motivation for engaging in social action is a valuable approach to better understanding donation behavior and, consequently, addressing the social problem of materiel convergence in the postdisaster environment.  相似文献   
2.
Emergency material allocation is an important part of postdisaster emergency logistics that is significant for improving rescue effectiveness and reducing disaster losses. However, the traditional single‐period allocation model often causes local surpluses or shortages and high cost, and prevents the system from achieving an equitable or optimal multiperiod allocation. To achieve equitable allocation of emergency materials in the case of serious shortages relative to the demand by victims, this article introduces a multiperiod model for allocation of emergency materials to multiple affected locations (using an exponential utility function to reflect the disutility loss due to material shortfalls), and illustrates the relationship between equity of allocations and the cost of emergency response. Finally, numerical examples are presented to demonstrate both the feasibility and the usefulness of the proposed model for achieving multiperiod equitable allocation of emergency material among multiple disaster locations. The results indicate that the introduction of a nonlinear utility function to reflect the disutility of large shortfalls can make the material allocation fairer, and minimize large losses due to shortfalls. We found that achieving equity has a significant but not unreasonable impact on emergency costs. We also illustrate that using differing utility functions for different types of materials adds an important dimension of flexibility.  相似文献   
3.
中国是粮食生产大国和人口大国,粮食问题对于我国经济社会的发展具有举足轻重的影响。现有粮食供应链"层层批发"的流通体制不能满足消费者个性化需求。所以,本文基于客户的个性化需求,应用轮询系统理论来研究面粉、大米等粮食连续物料的订单分拣自动化控制机理。本文根据实际业务需求设定普通订单、优先订单,对优先订单的分拣实行完全服务控制策略,对普通订单分拣实行限定(k=1)服务控制策略,建立完全-并行限定(k=1)的二级优先级订单分拣轮询控制系统模型,确保优先业务订单顾客得到更优质服务,同时保证订单分拣系统的公平性。采用嵌入式Markov链、多维概率母函数和拉式变换求解理论模型,并通过数值计算分析,精确求解其一阶系统特性、二阶系统特性等关键性能参数,从而深入研究连续物料订单分拣的控制机理。  相似文献   
4.
大规模地震后应急物资的高效保障是应急救援有效开展的必要前提。震后应急物资运输与配送包括从区域储备仓库和外围物资集散地运输到区域应急配送中心、由区域应急配送中心配送到各个受灾点两个阶段。应急物资保障具有持续时间长、需求紧迫性强和物资相对短缺等特点。本文以应急物资保障时效性与分配公平性为目标,建立了考虑多种运输方式、多时段动态的应急物资配送中心选址与运输配送路径优化的多目标规划模型,并基于此模型设计了一种带精英策略的非支配排序的遗传算法,以九寨沟地区地震灾难情景对模型进行实证研究,验证了模型和算法的有效性,以期为震后应急物资保障提供理论指导与决策支持。  相似文献   
5.
考虑不同的位移边界条件,建立了常物性2D-FGM板研究模型,并采用有限元法,得到其冷却瞬态热应力场分布图形。位移边界条件对常物性2D-FGM平面区域冷却瞬态热应力分布影响颇大,在简支和一端固定情况下,2D-FGM板自由边界上的热应力σx=0;两端固定情况下,其左右两边界均形成上中下三个应力聚集,应力分布形状和数值都发生了巨大的变化;将四周均设置呈固定约束后,热应力数值增长幅度较两端固定情况时更为明显。此结果为该材料的设计、制备提供了准确的理论计算依据。  相似文献   
6.
In 1413 at the death of his wife Guillemot, Jean Aubert, a group of witnesses and a clerk of the local mayoralty met to value the possessions of their residence, resulting in an inventory full of notes and values on rooms and their objects. Within the existing historiography of the Burgundian Netherlands and its northern European neighbours, inventories and their objects tend to be analysed from two perspectives: the Burgundian court and the ‘consumer revolution’. Applying insights from Erving Goffman and Bruno Latour, this article suggests a third perspective should have priority: the urban ‘theatre’ within which objects were documented and placed. Therefore it sets up an alternate methodology which begins with the inventory to build a picture of the theatre (the urban context and residence), the actors (the Aubert family) and the audience (the witnesses of the inventory) to establish new insights into the operation of Burgundian power and the dynamics of the ‘consumer revolution’.  相似文献   
7.
工科院校音乐选修课教材的分析和设想   总被引:2,自引:0,他引:2  
作为选修课身份出现的音乐教育对工科院校学生的特殊意义和作用已经被越来越多的人认同,而实现其音乐教育价值的关键所在就是在合理原则下对音乐选修课教材的选择和使用。本文从目前音乐选修课对工科院校学生的特殊作用入手,对音乐选修课教材进行分析、比较,针对工科大学生的特点,提出以“为学生服务”为宗旨的教材选用的方案。  相似文献   
8.
凝析气藏存在复杂的相变与相态分布,当地层压力下降到露点压力以下时,凝析油会在地层和井筒中分别析出,导致井口产气量、产油量与井底产气量、产油量之间存在质量转换,但仍遵循质量守恒定律。因此利用质量守恒建立考虑油、气两相的渗流微分方程,通过引入两相拟压力函数,推导凝析气井不稳定产能方程。在此基础上,结合物质平衡方程,利用生产动态数据拟合整个历史生产过程,不但可以获得气井目前的产能,还可以获得地层压力及各种地层参数。实例分析表明,计算结果准确可靠,有利于在凝析气井中推广使用。  相似文献   
9.
This article examines the change in Turkish domestic space through modernization and, in particular, the artifact of lace, as a nonchanging object in Turkish home in its relationship with the “traditional” and the “modern” domestic settings. Thereby it investigates how traditional and modern settings are defined in Turkish society and, this leads to a further analysis of the modernization process in Turkey within the scope of Turkish house and its domestic settings. The aim of the article is to analyze lace as an agent, which is an actant of the change in domestic settings, to read the connection between the daily life of people and social lives of artifacts. Therefore, examining the dialogue of lace with traditional and modern domestic settings provides to deconstruct the network of the artifact, the house and the individual during the modernization process that Turkish society has been through. The theoretical perspective of the article relies on a material‐semiotic approach with an emphasis on Latour's Actor‐Network Theory and, the methodology of the article is based on ethnography: It includes observations and semi‐structured interviews conducted with people from different social environments focusing on the meaning and the use of lace in domestic environment.  相似文献   
10.
由材料发展引发的一系列关于建筑装饰设计创新的概念,其主要的目的就是更好将建筑装饰设计与材料运用结合起来。只有通过建筑装饰材料的更新与发展,才能达到将建筑装饰设计艺术、技术结合起来快速发展的目标。从建筑装饰材料发展的历史入手,分析建筑装饰材料使用现状,结合材料特性、绿色环保、智能材料、节能材料、低碳等角度对未来材料的可能性发展方向及其对建筑装饰设计的影响进行探讨,总结归纳材料发展对建筑装饰设计影响的一般性规律,促进建筑装饰设计文化的发展与繁荣,营造宜居人居环境。  相似文献   
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