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51.
Models for the distribution of relief supplies often assume immediate availability of relief items upon the occurrence of a natural disaster. However, such an assumption does not always apply in realistic settings. In some cases, at least it is necessary to assemble relief items into kits before distributing them among the affected population. This paper presents a rolling horizon methodology that considers dynamic parameters such as demand, capacities and demand priorities for the problem of distributing relief supplies after the occurrence of a natural disaster by including such assembling activities before the delivery.  相似文献   
52.
Electricity generation capacity expansion is driven by both economic and socio-political realities. Policy makers determine public infrastructural decisions, such as climate and renewable targets, and transmission infrastructure, and the optimal generation capacity expansion follows. Policy makers therefore require planning models that can determine the optimal generation capacity mix in the long run under various scenarios, including policy choices. This work presents a planning model based on linearised alternating current optimal power flow which determines optimal generation capacity expansion and operation, in a least-cost manner, given global and local technical constraints, as well as policy decisions. We apply the model to a test case of the island of Ireland, which has two weakly interconnected systems, high renewable generation targets and low storage and interconnection. We determine the optimal generation expansion and operation out to 2030 considering the effects of increased multi-area interconnection, existing fossil fuel generation phase-out and increased renewable generation targets and carbon prices. Our results find that costs and emissions are driven primarily by the decommissioning of old inefficient generation units. High renewable targets, on the other hand, render increased carbon prices relatively ineffective in reducing system emissions. Furthermore, high renewable generation targets crowd out low-carbon power generation options such as carbon capture and storage (CCS). The strategic north-south interconnection has little effect on renewable energy source installations required to achieve renewable power generation targets but does impact on security of supply and the congestion level across the island.  相似文献   
53.
The introduction of automated vehicles (AVs) is a virtual certainty. Much less certain is the timing of their introduction and how rapid the transition to full automation will be. Various governments are already working to facilitate this shift by, for example, amending and elaborating regulations to support the introduction of AVs, or supporting tests in different urban environments. Meanwhile, urban and regional planners and decision-makers are still grappling with the uncertainties and differing opinions about the possible impacts of AVs on land-use changes and location choices, particularly in relation to the space available for vehicles, both moving (i.e. roadspace) and stationary (i.e. parking space). This paper uses a backcasting approach to identify critical policy decisions and measures to be taken before the implementation of AVs, so as to achieve a more desirable, attractive and high-quality city. These policy measures primarily relate to the reuse and reallocation of parking and roadspace. Two strategic decisions are found to be essential to meet the major goals of sustainable and liveable cities: a clear commitment to a shared mobility and the delimitation of Core Attractive Mixed-use Spaces (CAMS). In order to deliver these desired urbanisation patterns, a set of three policy paths, involving eight policy packages, is proposed for the next 20–30 years. This article provides urban and regional decision-makers with examples of interventions that can be implemented beyond and during the implementation of AVs.  相似文献   
54.
从航班计划优化的不同时间阶段分析,可以将航班计划优化分为航班计划静态编排优化、基于航班延误预测的航班计划动态反馈优化和基于机场协同决策(A-CDM)的航班计划动态调整角度三类;进而从航班时刻、机型指派、航班频率等编制环节分析了航班计划静态编排优化;随后利用延误波及预测与数据挖掘预测的优化方法分析了基于航班延误预测的航班计划动态反馈优化的相关研究。最后,根据航班计划优化复杂性分析,给出了航班计划优化的发展趋势和未来研究方向。  相似文献   
55.
张支南  浦正宁  李明 《技术经济》2020,39(5):116-124
为考察全球价值链分工的宏观经济效应,本文基于2000—2014年全球102个经济体相关数据,探究了全球价值链贸易对国际经济周期协同性的影响。结果表明,全球价值链贸易深化了国际垂直型分工,显著提升了国际经济周期的协同性;无论是制造业还是服务业价值链贸易,对国际经济周期协同性都具有显著正向影响,侧面反映出服务业也在越来越深入地融入全球分工体系;价值链贸易对国际经济周期协同性的影响效应主要体现于发展中与发达经济体之间,发达经济体之间的经济周期协同性受其影响并不明显。  相似文献   
56.
This research investigated how and under what conditions thriving at work affects career attitudes and behaviors. Using an experimental design (n = 174), Study 1 found that the effects of thriving on career satisfaction, career commitment, and career engagement were mediated by career resilience. The positive effect of thriving on career resilience and the resilience‐mediated effects of thriving on career satisfaction, commitment, and engagement were stronger when achievement orientation was higher. Study 2 verified these findings with a survey of another sample of 296 employees. These studies offer important insights for human resource managers and career consultants or practitioners regarding what may enhance employees' career outcomes. Our findings imply that thriving‐enabling practices might be beneficial among highly achievement‐oriented employees.  相似文献   
57.
The research aims to investigate business value critical success factors (CSFs) of enterprise systems (ES) through their life cycle in pursuit of resilient smart factory for emerging aircraft industry. This article provides an extensive literature analysis of past 22 years based on conscientious criteria of authors: (i) who have published strategic content relevant to CSFs, (ii) received more than 300 citations and (iii) concurrently published two or more papers relevant to ES CSFs. The most cited strategic CSFs were termed as classical CSFs. The 22 CSFs were identified, validated and synthesised for better understanding of success across life cycle by aircraft industry experts. The top 10 empirically verified CSFs have numerous differences with past generic classical CSFs. This article canvases real insights of two distinct views: process and variance approaches of the ES CSFs. The process approach, which is a neglected research area, facilitates the researchers for identification of ES life cycle process coupled with a view of resource deployment when it is needed the most. While the variance approach facilitates practitioners and researchers in finding out which resource (CSF) is relatively more important. The significant findings for ES life cycle can help the practitioners and researchers to make rational decisions throughout the ES life cycle.  相似文献   
58.
目前,员工过劳问题在我国企业发展中日益凸显,需要予以重视和解决。基于个体与组织互动角度,通过对338名企业员工的问卷调查分析职业延迟满足和职业成长机会对员工过劳的影响,并检验职业成长机会对职业延迟满足影响员工过劳的调节作用,结果表明:职业延迟满足的两个维度(工作延迟满足和职业生涯延迟满足)均对员工过劳有显著正向影响,而职业成长机会对员工过劳有显著负向影响;职业成长机会对职业延迟满足影响员工过劳具有负向调节作用,即职业成长机会越大,职业延迟满足与员工过劳的正向关系越弱。因此,企业管理者应合理引导和帮助员工做好职业生涯规划,为员工提供合适的多元化发展通道,以有效预防和缓解员工过劳。  相似文献   
59.
为了实现产品生产阶段到服务阶段业务与数据的有效集成,从业务层和数据层对制造服务系统中的大修维护维修(MRO)与企业资源计划(ERP)的集成过程进行了建模与分析,对ERP与MRO系统之间的业务过程和信息交互过程进行了分析,建立了二者的业务集成框架模型,分析了ERP与MRO系统的数据结构转换过程,提出了二者数据集成模型。应用Web Services完成了ERP与MRO的系统集成开发,包括服务BOM集成、备品备件管理集成等。研究结果实现了制造和服务阶段关键产品数据信息的集成与反馈,打通了从制造到服务阶段的数据传递与集成,对进一步研究复杂产品生命周期管理的信息集成具有一定的借鉴意义。  相似文献   
60.
This paper addresses the debate over aggressive tax‐planning models and analyzes the role of tax consultants. It focuses on the dynamic interaction between innovation and imitation of aggressive tax‐planning products and governmental tax regulation, and it highlights the importance of the length of regulatory lag in comparison with the time it takes the tax‐consulting industry to imitate newly innovated tax‐avoidance products. It reveals an alignment of interests between highly innovative tax‐consulting firms and the governmental tax legislator/regulator. The conclusions are also relevant for the policy debate on mandatory disclosure rules about aggressive tax‐planning models.  相似文献   
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