资源环境约束下中国TFP增长的空间差异和影响因素

运用DDF模型和ML生产率指数,对中国分省资源环境约束下的区域全要素生产率进行测算,采用Theil指数测算资源环境约束下中国全要素生产率增长的地区差异并按照多种空间尺度进行区域分解;构建空间面板数据模型,采用广义空间面板自回归最小二乘法对资源环境约束下全要素生产率增长的影响因素进行实证研究。研究结果表明,在2010年之前,资源环境约束下中国全要素生产率增长的空间差异总体上呈下降态势,地区内而非地区间差距是造成总体空间差异的主要来源。空间计量模型回归估计结果表明,资源环境约束下全要素生产率增长存在显著的正向空间溢出效应,经济发展水平、贸易开放和科技创新水平对资源环境约束下全要素生产率增长存在显著的促进作用,产业结构、能源结构和要素禀赋结构等结构因素对全要素生产率增长存在显著的负向影响,外商直接投资和环境规制水平对全要素生产率增长的影响在统计上并不显著。     

自驾偏好、居民异质与居住选址——基于单中心城市模型的空间均衡分析

基于线性单中心城市模型,研究了自驾偏好和居民拥有车辆异质性对双方式交通走廊沿线居民出行方式选择和居住区位选址均衡的影响.将有车居民对自驾出行的偏好集成到直接效用函数中,建立了空间均衡模型.分析发现,当城市居民全部自驾出行时,租金-距离可能呈现先提高后降低的趋势.考虑只有部分居民拥有自驾车辆的一般情形,推导出了有车和无车居民在城市走廊沿线居住分布的不同均衡模式.通过理论解析,进一步考察了小汽车保有量和城市居民数量的变化对城市空间结构和居民效用水平的影响.     

创新活动空间集聚及其驱动因素国外研究进展评述

对国外有关创新活动空间集聚的研究文献进行梳理,分析了现有研究取得的成就和存在的问题,对未来研究的几个待突破的方面进行了展望。     

Flood Catastrophe Model for Designing Optimal Flood Insurance Program: Estimating Location‐Specific Premiums in the Netherlands

As flood risks grow worldwide, a well‐designed insurance program engaging various stakeholders becomes a vital instrument in flood risk management. The main challenge concerns the applicability of standard approaches for calculating insurance premiums of rare catastrophic losses. This article focuses on the design of a flood‐loss‐sharing program involving private insurance based on location‐specific exposures. The analysis is guided by a developed integrated catastrophe risk management (ICRM) model consisting of a GIS‐based flood model and a stochastic optimization procedure with respect to location‐specific risk exposures. To achieve the stability and robustness of the program towards floods with various recurrences, the ICRM uses stochastic optimization procedure, which relies on quantile‐related risk functions of a systemic insolvency involving overpayments and underpayments of the stakeholders. Two alternative ways of calculating insurance premiums are compared: the robust derived with the ICRM and the traditional average annual loss approach. The applicability of the proposed model is illustrated in a case study of a Rotterdam area outside the main flood protection system in the Netherlands. Our numerical experiments demonstrate essential advantages of the robust premiums, namely, that they: (1) guarantee the program's solvency under all relevant flood scenarios rather than one average event; (2) establish a tradeoff between the security of the program and the welfare of locations; and (3) decrease the need for other risk transfer and risk reduction measures.     

Spatial Risk Analysis of Power Systems Resilience During Extreme Events

The increased frequency of extreme events in recent years highlights the emerging need for the development of methods that could contribute to the mitigation of the impact of such events on critical infrastructures, as well as boost their resilience against them. This article proposes an online spatial risk analysis capable of providing an indication of the evolving risk of power systems regions subject to extreme events. A Severity Risk Index (SRI) with the support of real‐time monitoring assesses the impact of the extreme events on the power system resilience, with application to the effect of windstorms on transmission networks. The index considers the spatial and temporal evolution of the extreme event, system operating conditions, and the degraded system performance during the event. SRI is based on probabilistic risk by condensing the probability and impact of possible failure scenarios while the event is spatially moving across a power system. Due to the large number of possible failures during an extreme event, a scenario generation and reduction algorithm is applied in order to reduce the computation time. SRI provides the operator with a probabilistic assessment that could lead to effective resilience‐based decisions for risk mitigation. The IEEE 24‐bus Reliability Test System has been used to demonstrate the effectiveness of the proposed online risk analysis, which was embedded in a sequential Monte Carlo simulation for capturing the spatiotemporal effects of extreme events and evaluating the effectiveness of the proposed method.     

Disentangling the Governance Configurations of Strategic Spatial Plan-Making in European Urban Regions

This paper is aimed at assessing and disentangling how territorial governance configurations influence contemporary practices in strategic plan-making in 14 European urban regions. The findings allow us to distinguish three dominant practices: i) plan-making shaped by consensus building and multilevel government cooperation; ii) plan-making shaped by the involvement of profit-oriented actors and negotiations, and iii) plan-making shaped by consolidated planning practice. To truly grasp plan-making practice, it is necessary to scrutinize who rules and who is ruled while negotiations are unfolding, as well as the extent to which private actors’ interests influence how spatial development goals and strategies are defined.     

扁平超宽连续箱梁桥空间受力性能分析与研究

扁平超宽箱梁桥由于具有较大的宽跨比，其受力性能呈现明显的空间效应，通常的单梁模型计算已不能满足设计的精度要求，主要体现在宽箱梁各腹板纵向受力的差异性以及明显的剪力滞效应，同时由于大宽跨比使得横向预应力的作用不仅增加了顶板的压应力，也使得整体箱梁截面下缘出现拉应力，造成边腹板底部纵向裂缝，这些都给宽箱梁的设计带来了不利。因此为研究宽箱梁的空间效应，本文运用ANSYS有限元软件建立了全桥实体模型，计算了各腹板纵向受力差异及剪力滞效应，以及横向预应力对箱梁横向受力的影响，得到了一些有益的结论，为设计人员提供一定的参考。     

Reframing Resilience: Equitable Access to Essential Services

We urgently need to put the concept of resilience into practice if we are to prepare our communities for climate change and exacerbated natural hazards. Yet, despite the extensive discussion surrounding community resilience, operationalizing the concept remains challenging. The dominant approaches for assessing resilience focus on either evaluating community characteristics or infrastructure functionality. While both remain useful, they have several limitations to their ability to provide actionable insight. More importantly, the current conceptualizations do not consider essential services or how access is impaired by hazards. We argue that people need access to services such as food, education, health care, and cultural amenities, in addition to water, power, sanitation, and communications, to get back some semblance of normal life. Providing equitable access to these types of services and quickly restoring that access following a disruption are paramount to community resilience. We propose a new conceptualization of community resilience that is based on access to essential services. This reframing of resilience facilitates a new measure of resilience that is spatially explicit and operational. Using two illustrative examples from the impacts of Hurricanes Florence and Michael, we demonstrate how decisionmakers and planners can use this framework to visualize the effect of a hazard and quantify resilience-enhancing interventions. This “equitable access to essentials” approach to community resilience integrates with spatial planning, and will enable communities not only to “bounce back” from a disruption, but to “bound forward” and improve the resilience and quality of life for all residents.     

元前文献图籍所载黄河河源

有关黄河河源的概念，古代各种史学、地理、以及宗教文献都有相关记载。早期文献中提出的重源潜流的概念，也为塑造河源空间概念留下了发挥余地。及至唐朝，各种类书、笔记、野史关于位于境外的河源的著述沿用了上述文献中已有的地理知识，并融入了佛教世界观的空间概念以及唐代实地考察的纪录，逐渐构成了河源这一多元化的空间想象。本文探讨了不同知识框架对唐代河源记载的影响，以及在几幅现存宋代地图上所反映出的相关影响。这类文献资料有助于我们理解中古地理知识的深化与演变，以及后代地图上展示河源的更丰富的地图表现形式。     

空间批评视角下的《生日》

从空间批评视角看,文本中的空间不再是静止的＂容器＂,而是一种蕴含多维文化信息的指涉系统,注重文本中空间的社会、文化属性。在美国华裔作家雷祖威的短篇小说《生日》中,与华裔青年华莱士·王的爱情故事相关的几个空间场景不仅再现了华裔的现实生活世界,更充分展示了他们居于社会边缘的处境与内心疏离的痛苦。