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81.
With the acceleration of China’s urbanization, the functions and benefits of mega-projects are required higher. With the deepening of “the Silk Road Economic Belt and the 21st-Century Maritime Silk Road”, the quantitative evaluation of multinational investment projects will help strengthen cross-border communication among government, society and enterprises, which provide a basis for mutual trust. This study empirically analyzes and evaluates the impact of mega-projects on carrying capacity of cities, by using the DID method based on the panel data of 15 cities in China from 2000 to 2013. The results show that the construction and operation of the first-line project of the West-East gas pipeline has a significant positive impact on the improvement of carrying capacity of cities along the line. However, the degree of impact on three dimensions is slightly different. The impact on the social carrying capacity is the greatest, then the ecological and economic carrying capacity. Therefore, the decisions of domestic mega-projects should be unified with urban planning to promote the sustainable development of China’s economy and social. The investment of mega-projects abroad should also be coordinated with the carrying capacity of host cities, in order to enhance the competitiveness and creativity of Chinese multinational mega-projects investment.  相似文献   
82.
ABSTRACT

Land market regulations are often justified by the assumption that activities of foreign and non-agricultural investors drive up prices in domestic land markets. However, empirical knowledge about the dynamics of agricultural land prices across borders is sparse. Using the German reunification as a natural experiment, we study the effect of the former inner German border on the dynamics of agricultural land prices in East and West Germany. We apply a land price diffusion model with an error correction specification to analyse spatial agricultural land markets. A novel feature of our model is its ability to distinguish price diffusion within states and across state borders. We provide evidence for a persistent border effect given that the fraction of spatially integrated counties is larger within states than across the former border. Moreover, we observe non-significant error correction terms for many counties along the former border. From a policy perspective, it is striking to realize that even 25 years after German reunification, pronounced land price differences persist. It is quite likely that price diffusion through existing borders within the EU would take even more time given language barriers, different institutional frameworks, and information asymmetries between domestic and foreign market participants.  相似文献   
83.
ABSTRACT

A comparative analysis of population dynamics worldwide contributes to profile distinctive demographic and economic trajectories of urban growth, discriminating processes of settlement concentration or dispersion under sequential cycles of urbanization. However, a wide-ranging characterization of urban cycles based on demographic dynamics worldwide is still missing. The present work is aimed at filling such a gap analysing long-term changes (1950–2030) in annual population growth rate of 1691 urban agglomerations with more than 300,000 inhabitants in 74 world countries. Results of this study indicate that metropolitan growth worldwide was associated with largely variable rates of population growth, highly positive before 2000 and progressively reducing over recent decades. Despite important differences at continental (and country) scale, demographic expansion of urban agglomerations showed two contrasting phases with a break point in the 1980s denoting a progressive reduction in spatial heterogeneity of population growth rates and a moderate slowdown in demographic dynamics. Intensity of urban expansion and spatial heterogeneity in population growth rates across metropolitan agglomerations evidences a trade-off between fast and slow demographic dynamics. These findings can be better understood to support theories of sequential city growth, making a suitable contribution to policy making, especially in countries where urban population is expanding more rapidly.  相似文献   
84.
Abstract:

This article is a response to two crucial ideas about progressive institutional change: the first is J. Fagg Foster’s principle of “minimal social dislocation,” which asserts that socio-economic changes should be implemented gradually, to avoid unraveling the social fabric of the community; the second is Karl Polanyi’s principles of redistribution of rights and powers by relevant authorities and reciprocity, a symmetrical and highly personalized exchange system, which is likewise a protective mechanism that society employs against anonymity and disintegration brought about by unregulated market. Using lessons learned in the thirty-year transition to market in post-Soviet countries, this article argues that to commence progressive institutional change in the honesty- and transparency-resistant cultures of former Soviet states, impersonal exchange and impartial rule of law must be given far greater weight than personalization of contacts and continuation of cultural traditions.  相似文献   
85.
This paper focuses on a new strand of research that uses stochastic approach for making spatial price comparisons. We propose a novel method to account for the presence of spatial dependencies in consumer prices and consequently in price indexes by imposing penalization conditions on the estimation of traditional CPD models leading to the spatially-penalized country-product-dummy (SP-CPD) model. The paper proposes an appropriate estimation strategy, which enables us to simultaneously estimate all the parameters in the model, including the smoothing parameter of the penalization term instead of determining it externally. In order to estimate spatial price indexes for areas lacking in price data, we suggest applying the kriging methodology to the price indexes obtained from the SP-CPD model. This new approach is applied to official Italian CPI data for constructing regional spatial price indexes for 2014. The results show that price levels are higher in the Northern-Central regions than in the South.  相似文献   
86.
It is crucial to develop appropriate strategies to reduce the evacuation time in a disaster situation. The negative impact of large scale disasters can be mitigated by proactive and efficient (time optimal) evacuation planning. The present study aims to develop strategies for public transit-based evacuation for better control and reduced congestion. Mathematical models are formulated for both strategic and operational aspects of evacuation planning to result in efficient, optimal evacuation. The study also presents methods to manage the external environment uncertainties, in particular, evacuation demand uncertainty, by providing robust solutions. To test the efficacy of the models, a case study for a radiological accident in a nuclear plant in India is presented. The results of the case study demonstrate that the models can provide live, efficient and robust results during actual emergencies in acceptable time.  相似文献   
87.
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   
88.
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   
89.
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   
90.
依据城镇化发展过程中要素空间集聚理论,展开区域经济发展的空间经济结构研究。通过城市引力、克鲁格曼指数计算,比较分析城镇群内部城市吸引力和城市产业分布的差异性,通过人口与生产空间分布集中度指标和不一致系数的测算,分析了山西省城镇群空间要素集聚效应。研究表明,山西省的城镇群规划与要素空间集聚趋势整体一致,城市间产业分工体系基本形成,城镇群的要素集聚效应明显,但人口与生产分布仍存在不一致性。研究认为,山西省城镇群发展应该继续明确各城市的产业分工和特色,引导劳动力和资本要素的合理流动,实现人口与生产空间分布的一致。  相似文献   
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