Individual Accessibility Revisited: Implications for Geographical Analysis in the Twenty‐first Century

Analytical methods for evaluating accessibility have been based on a spatial logic through which the impedance of distance shapes mobility and urban form through processes of locational and travel decision making. These methods are not suitable for understanding individual experiences because of recent changes in the processes underlying contemporary urbanism and the increasing importance of information and communications technologies (ICTs) in people's daily lives. In this paper we argue that analysis of individual accessibility can no longer ignore the complexities and opportunities brought forth by these changes. Further, we argue that the effect of distance on the spatial structure of contemporary cities and human spatial behavior has become much more complicated than what has been conceived in conventional urban models and concepts of accessibility. We suggest that the methods and measures formulated around the mid‐twentieth century are becoming increasingly inadequate for grappling with the complex relationships among urban form, mobility, and individual accessibility. We consider some new possibilities for modeling individual accessibility and their implications for geographical analysis in the twenty‐first century.     

西部民族经济跨越式发展的途径

跨越式发展是一个过程,是经济发展质量和水平的整体跃升。正确理解跨越式发展的思想理论,对中国西部民族地区经济发展具有重要的理论和现实指导意义。     

Accompaniment Through Carceral Geographies: Abolitionist Research Partnerships with Indigenous Communities

This article approaches “ea”—a Kanaka Maoli (Native Hawaiian) concept meaning life, breath, and sovereignty—as a vital mode of abolition ecologies, and proposes accompaniment as a methodology for mutual collaboration toward this endeavour. Research draws from ethnographic fieldwork on the Wai‘anae Coast of O‘ahu in Hawai‘i, a predominantly Native Hawaiian community, and reflects upon the author’s positionality on Wai‘anae’s insider–outsider borderlands. The argument is multifold: Carceral geographies inscribe racism by cleaving humans from the environment and each other, depriving life‐giving resources from populations deemed a threat to a dominant socioenvironmental order. At the same time, abolition ecologies entail worldmaking predicated on the interdependence of all life forces, employing syncretic practices that join disparate struggles, people, and places to generate possibilities greater than the sum of its parts. Accompaniment works against racism’s practices of criminalisation and containment while contributing to radical, syncretic placemaking as part of an expansive liberatory practice.     

大都市区居民对新兴边缘城市的认知与迁居意向——以天津大都市区为例

目前天津经济技术开发区(TEDA)已发展成为天津大都市区的新兴边缘城市。本文以居民问卷调查的第一手资料为基础,分析天津大都市区内各地区居民对TEDA的认知程度与迁居意向以及地域选择性特征,为以TEDA为核心的人口反磁力中心建设为主导的天津大都市区人口调整对策提供科学依据。     

Negotiating belonging and perceptions of citizenship in a transnational world: Singapore,a cosmopolis?

The complex mappings of inflows and outflows of people, capital, images and ideas in global city spaces create particular challenges for nation-states that are deeply embedded in the international circuit of capital. Through an empirical study of Singapore, an aspiring global city-state, I offer an analysis of how the state-sponsored cosmopolitan project is contested by Singapore citizens. I also present evidence to highlight the contradictions of belonging and citizenship in a transnational world, with particular reference to the postcolonial racial and nationality dynamics that inflect these discourses.

Négocier l'appartenance et les perceptions de la citoyenneté dans un monde transnational: Singapour comme ville cosmopolite?

Les mappages complexes des mouvements des personnes, du capital, des images et des idées à travers les espaces urbains mondiaux posent un défi particulier aux états-nations qui sont très fortement intégrés dans le circuit international du capital. Singapour, ville-état mondiale en croissance, est le sujet d'une étude empirique dans laquelle je présente une analyse du projet cosmopolite soutenu par l'état et comment ce projet est contesté par les citoyens de Singapour. Je présente également des éléments de preuve pour faire ressortir les contradictions entre l'appartenance et la citoyenneté dans un monde transnational, en précisant entre autres les dynamiques qui touchent aux identités raciales et nationales postcoloniales qui pèsent sur ces discours.

Mots-clefs: appartenance, citoyenneté, mobilité transnationale, cosmopolitanisme, Singapour.

La negociación de pertenencia e ideas de ciudadanía en un mundo transnacional: Singapur, ¿un cosmópolis?

Los complejos mapeos de la entrada y salida de personas, capital, imágenes e ideas en los espacios de ciudades globales crean desafíos particulares para naciones-Estados, los cuales están estrechamente vinculados al circuito internacional de capital. Por un estudio empírico de Singapur, que aspira a ser reconocido como ciudad-estado global, ofrezco un análisis de cómo los ciudadanos de Singapur contestan este proyecto cosmopólito patrocinado por el Estado. También presento pruebas para destacar las contradicciones inherentes en las nociones de pertenencia y ciudadanía en un mundo transnacional, con referencia particular a la dinámica racial y de la dinámica de nacionalidad poscolonial que salpican estos discursos.

Palabras claves: pertenencia, ciudadanía, movilidad transnacional, cosmopolitanismo, Singapur.     

A new fossil genus in Pamphiliidae (Hymenoptera) from China

A new genus with two new species, Scabolyda orientalis gen. et sp. nov. and Scabolyda incompleta sp. nov., assigned to the subfamily Juralydinae in the family Pamphiliidae are described and illustrated. They were collected from the Middle Jurassic Jiulongshan Formation and the Lower Cretaceous Yixian Formation in northeastern China. They represent the first fossil pamphiliids described from China.     

Seismic Overstrength of Shear Walls in Parking Structures with Flexible Diaphragms

The objective in current design practice for parking structures is that energy is dissipated through the formation of plastic hinges at the base of shear walls while floor diaphragms remain elastic and are vertically supported by a combination of shear walls and gravity resisting columns. Unfortunately, this objective is not always achieved due to inaccuracies in current methods for calculating demands on shear walls and in calculating the capacity of shear walls (IBC 2003 International Building Code. International Conference of Building Officials. Whittier, CA.  [Google Scholar], ACI code). When demands are overestimated and capacity underestimated, then diaphragm can fail prior to flexural yield of shear walls as was observed in several parking structures in the 1994 Northridge earthquake.

Eigenvalue and inelastic dynamic response analyses were performed in order to investigate the effects of diaphragm flexibility on wall responses and of wall overstrength on diaphragm responses. The elongated periods of parking structures due to diaphragm flexibility were found to significantly decrease seismic force demand on shear walls relative to what is calculated using codes of practice in which diaphragms are assumed to be rigid. This leads to the over design of shear walls, which further compounds the problem by preventing the flexural yielding of these walls and thereby driving inelastic response to diaphragms. Various degrees of diaphragm flexibility, shear wall layout, seismic zone, and the number of stories were considered in these analyses.

Inelastic static pushover analyses were preformed to investigate the design and capacity evaluation of shear walls. The results illustrate that the shear capacity of walls may be close to twice that calculated by codes of practice. The largest overstrengths were observed in shear walls with low height-to-length ratios in which a significant portion of the lateral load was taken by direct strut action to the foundation and without placing demands on the longitudinal tension reinforcement in the shear walls. The article concludes that methods in codes of practice for calculating shear wall demands and capacities need to be improved if good seismic performance of parking structures is to be achieved.     

浅谈麦积山石窟文物资源数字化建设

文物资源如何加快拓宽数字化实用技术应用,探索生存与发展空间,主动跨入数字化时代,是当前文博业面临的主要问题。为充分发挥文博业石窟文物资源特色化信息资源的功能,最大限度地满足社会信息需求,服务于科研、经济建设和社会发展,文物资源数字化建设工作显得尤为重要。本文针对麦积山石窟文物资源的特征、现状,依据文物文献资源数字化发展的特点和客观趋势,理论联系实际,介绍了麦积山文物资源数字化发展的现状,并就麦积山文物资源数字化硬件建设、文物数字化管理技术和数字化建设等问题作了初步探讨。     

中国传统灰土灰浆强度增强方法研究

中国传统灰土灰浆中水硬性凝胶材料-水合硅酸钙和水合硅酸铝的形成可以大幅度提高其强度,但在自然条件下生成此类水硬性化合物需要很长时间。本文借鉴现代水泥工艺中利用焙烧黏土材料可提高火山灰活性的原理,从而有效缩短形成水硬性化合物的反应时间,在短时间内大大提高灰浆的强度。以此为出发点,加工制备性能优良的灰浆材料,为传统砌体建筑的保护提供适宜的保护修复材料。