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61.
针对突发事件下的应急物资调运问题,考虑了多个地区同时受灾以及多个出救点需要对其进行救灾并且各出救点的运力有限的情况,以最小化总的车辆运输费用,最大化救灾效率、各受灾点的救灾满意度,以及各受灾点得到救助的公平性为目标,建立了该问题的多目标混合整数非线性规划模型,并提出了一个基于两层架构协调的迭代式遗传算法进行求解。基于仿真数据的实验结果证明了所提出的模型和算法的有效性。  相似文献   
62.
State capacity has become one of the most discussed concepts in development economics and political economy. In this survey we argue that the study of economic history provides vital insights into the process through which modern states have acquired ‘state capacity’. By evaluating the process of state building across a range of different countries in Europe and Asia, we are able to ‘decompress’ the relationship between state capacity and economic growth. Our analysis emphasizes the variegated nature of the state building process. We focus on recent research that helps to elucidate the mechanisms that relate state capacity to economic growth.  相似文献   
63.
[目的]碳足迹及碳承载力的时空演变分析是当前分析温室气体排放量的热点问题。[方法]文章采用2004~2014年河北省化石能源消费数据、土地利用结构数据以及经济社会数据,通过构建碳足迹模型,基于Arc GIS平台对河北省11个地级市的碳足迹、碳承载力、净碳足迹进行时空演变分析。[结果](1)2004~2014年河北省碳足迹由2.224 5亿t增长至4.792 2亿t,其中煤炭能源消费量占90%左右,唐山、邯郸和石家庄碳足迹值较高,分别占河北省碳足迹的33%、18%和16%;(2)2004~2014年河北省碳承载力由9 043万t增长至1.050 6亿t,其中林地碳承载力占河北省碳承载力的97%左右,西南地区农、林业发达,碳承载力相对较高;(3)2004~2014年河北省净碳足迹呈逐年上升趋势,由1.536 7亿t增长至4.236 5亿t,唐山、邯郸及石家庄净碳足迹较大,分别占河北省净碳足迹的40%、22%和16%;(4)除保定外,其他10个地级市的碳足迹压力指数变化强度均呈现不同程度的增强趋势。此次研究成果将为河北省未来制定温室气体排放量等相关政策的建设提供参考。[结论]整体来看,河北省碳足迹及碳承载力呈逐年增长的变化趋势,应加强温室气体的管控力度,减小碳排放给河北省带来的负面影响。  相似文献   
64.
为利用投影寻踪(PP)技术科学,客观评价区域水资源可持续发展能力,基于生态环境、水资源和经济社会因素选取20个指标构建区域水资源可持续发展能力评价指标体系。利用新型仿生群体智能算法——凉亭鸟优化(SBO)算法优化PP技术最佳投影方向,提出SBO-PP水资源可持续发展能力评价模型,并构建灰狼优化(GWO)算法-PP模型、人工蜂群(ABC)算法-PP模型、差分进化(DE)算法-PP模型、地理生物学优化(BBO)算法-PP模型、粒子群优化(PSO)算法-PP模型作对比,以云南省2006—2015年及2020年水资源可持续发展能力评价为例进行实例研究。结果表明:SBO算法优化PP技术获得的适应度值优于GWO、ABC、DE、BBO和PSO算法,具有较好的求解精度、稳健性能和极值寻优能力。SBO-PP模型对云南省2006—2007年水资源可持续发展能力评价为"较差",2008—2015年评价为"中等",2020年评价为"较强"。  相似文献   
65.
以青海省为研究区域,以其所辖的8个行政分区作为研究单元,利用基于组合赋权的模糊物元分析法,从用水总量、用水效率、水质3个维度建立青海省水资源承载力的"三条红线"评价指标体系。结果显示:青海省水资源还具有较大的开发潜力,水资源承载能力较强。但是青海省水资源开发利用条件和程度呈现出区域性差异,西宁市和海东市水资源承载力已近饱和状态,而其余地区水资源承载力相对较强,必须因地制宜采取相应的改善措施。  相似文献   
66.
The attraction of foreign direct investment seeks, among other things, to increase the productivity of local companies through knowledge spillovers. However, the empirical evidence in this regard is contradictory. One influential factor is the absorptive capacity of the local companies. This article analyzes the effect of the presence of former employees of multinational corporations as employees of local companies, on the absorptive capacity of said companies. The study was done in Costa Rica, a country known for its successful strategy in the subject matter. The data come from a survey applied to 1167 companies by the Observatorio Costarricense de las Pymes in 2011. It was found that the hiring of former employees of multinational corporations by local companies has a positive effect on the index of absorptive capacity of companies in all productive sectors. Specifically, this hiring of former employees increases the index of absorptive capacity by nine percentage points, with differences by sector and the size of the company.  相似文献   
67.
This study demonstrates the use of importance–performance analysis (IPA) to prioritise the motivators that can facilitate university–industry collaboration in the animation industry in Taiwan. This study confirms that financial supports and education are still major reasons for academia to participate in the university–industry collaboration. Reducing costs and obtaining human training are the reasons for animation firms to join the university–industry collaboration. However, by comparing the results of IPA for academia and industry, this study recommends four common interest motivators from both academic and industrial perspectives and where efforts should be concentrated. Research facilities, external competencies, talents, and innovation capacity are very important for the animation industry of Taiwan.  相似文献   
68.
There have been repeated calls for a ‘new professionalism’ for carrying out agricultural research for development since the 1990s. At the centre of these calls is a recognition that for agricultural research to support the capacities required to face global patterns of change and their implications on rural livelihoods, requires a more systemic, learning focused and reflexive practice that bridges epistemologies and methodologies. In this paper, we share learning from efforts to mainstream such an approach through a large, multi-partner CGIAR research program working in aquatic agricultural systems. We reflect on four years of implementing research in development (RinD), the program’s approach to the new professionalism. We highlight successes and challenges and describe the key characteristics that define the approach. We conclude it is possible to build a program on a broader approach that embraces multidisciplinarity and engages with stakeholders in social-ecological systems. Our experience also suggests caution is required to ensure there is the time, space and appropriate evaluation methodologies in place to appreciate outcomes different to those to which conventional agricultural research aspires.  相似文献   
69.
可持续的产业发展分析往往关注于经济增长与资源、环境之间的互动影响,以及它们在最优增长路径上的动态分配过程,一般很少考虑产业依赖的资源与产业发展中环境诸要素(如衰减能力、环境本底值等)的背景条件不同而引发的耦合产业结构和规模的问题[1-14]。本文主要对基于资源消耗和可持续发展框架下耦合产业系统的最优化增长路径上产业结构的动态变化进行刻画和模拟实证。数值模拟显示,对于可持续的耦合产业系统长期发展而言,两个产业的结构和规模将随着环境诸要素动态变化,随之产生的社会效益和环境损害也是动态变化的。而且,资源的消耗水平、耦合产业中各子产业的发展结构、环境条件将影响到耦合产业系统的最优增长路径,在特定的情况下将出现类似于Kuznets曲线性状的拐点。  相似文献   
70.
Research Summary: We combine the absorptive capacity and social network theory approaches to predict how intrafirm “whole” network characteristics affect the firm's speed of absorption of external knowledge to produce inventions. We start from the widely accepted view that distant, externally‐developed knowledge is difficult to absorb into the focal firm's own knowledge production. We suggest that high levels of intrafirm inventor task network diversity and task network density are essential for a diversity of knowledge inputs and coordinated actions regarding knowledge transfer, which in turn, reduces problems related to the absorption of knowledge—especially in the case of knowledge that is distant from the focal firm. The results of an event history study of 113 pharmaceutical firms that engaged in technology in‐licensing from 1986 to 2003 provide general support for our hypotheses. Managerial Summary: Firms keen to keep up with an uncertain and ever‐changing industry environment, can benefit from the speedy introduction of inventions. We examine how firms absorb licensed‐in technologies to nurture the rapid development of own related inventions. We show that a firm's absorption speed depends on the characteristics of the internal collaboration networks among the firm's inventor employees. More specifically, technologically diverse and well‐connected inventor networks improve the firm's ability to absorb external technologies quickly. This applies especially to externally acquired technologies that are unfamiliar to the firm. Depending on the distance of the acquired technology from the focal firm combined with speed‐inducing inventor network characteristics, our estimates suggest that firms can reduce the time needed for absorption by several months.  相似文献   
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