中小城镇中心区的更新与改造初探--以陕西蒲城县中心区城市设计为例

中小城镇中心区是全镇居民的活动核心和对外窗口，其更新和改造是城镇建设的重中之重，对整个城镇的吸引力和稳定性产生重要影响。该文对陕西省蒲城县中心区城市设计进行深入思考，试图从空间层次、文化氛围和活动支持这三个具体操作层面入手探讨一套“适宜于中小型历史文化城镇中心区的设计方法”。     

论城市竞争的空间效应

全球化和地方化作为城市竞争力的外部环境因素,是城市竞争优势的重要源泉。同时城市通过竞争影响着全球化和地方化的过程,并在不同层面空间上投下其竞争效应的投影。在全球层面,城市竞争效应主要表现在全球城市体系的形成、首位城市主宰世界经济趋势明显、多极多层次世界城市网络体系的形成。在区域层面,城市竞争效应主要表现在区域产业集聚、城市集聚;在城市层面城市竞争效应主要表现在新产业空间与城市竞争。     

我国城市空间规划的理论与研究进展

近年来,我国城市空间研究成果非常丰富,但对于成果应用的研究比较薄弱,其不足表现在研究成果多为总结性、描述性和一般性,基础性的理论研究比较缺乏.寻求适宜于中国发展需要的城市空间结构增长模式及其规划调控机制,是将来城市空间研究的重点.应积极探讨新的城市空间规划技术方法,从城市空间设计转向城市空间政策的制定,开展城市空间规划的比较研究,进而建立有中国特色的城市空间规划体系.     

Contribution of marine and continental aerosols to the content of major ions in the precipitation of the central Mediterranean

The region of the investigated receptor is situated in the southern part of the Adriatic Sea in the Mediterranean. The measuring station is located on the seashore, which, being considered as a border area, is representative for the qualitative and quantitative estimation of the influence of marine and continental aerosols on the content of major ions in precipitation. In the sampling period, precipitation in the region of the investigated receptor was more abundant during the summer and autumn than during the winter and spring. The most frequent precipitation heights were up to 20 mm, while high precipitation came exclusively from the continental region. The results of the measurements of ions readily soluble in water were used for the differentiation of marine from continental contributions of primary and secondary aerosols to their content in the precipitation. Using PCA, it was shown that main contribution of Cl(-), Na(+) and Mg(2+) came from primary marine aerosols, while the contribution from continental sources was dominant for the content of SO(4)(2-), NO(3)(-), NH(4)(+) and Ca(2+) in the precipitation. The continental origin of Ca(2+) was from a primary source, while SO(4)(2-), NO(3)(-) and NH(4)(+) were representatives of secondary aerosols produced by reactions between acid oxides and alkaline species in the atmosphere, but SO(4)(2-) and NO(3)(-) also exist in the precipitation as free acids. The origin of the trace elements Cd, Cu, Pb and Zn in the precipitation came from anthropogenic emission sources. The results obtained in this work are based on experimental data from 609 samples collected during the period 1995-2000.     

Comparison of self-organizing maps classification approach with cluster and principal components analysis for large environmental data sets

Three classification techniques (loading and score projections based on principal components analysis (PCA), cluster analysis (CA) and self-organizing maps (SOM)) were applied to a large environmental data set of chemical indicators of river water quality. The study was carried out by using long-term water quality monitoring data. The advantages of SOM algorithm and its classification and visualization ability for large environmental data sets are stressed. The results obtained allowed detecting natural clusters of monitoring locations with similar water quality type and identifying important discriminant variables responsible for the clustering. SOM clustering allows simultaneous observation of both spatial and temporal changes in water quality. The chemometric approach revealed different patterns of monitoring sites conditionally named "tributary", "urban", "rural" or "background". This objective separation could lead to an optimization of river monitoring nets and to a better tracing natural and anthropogenic changes along the river stream.     

城市发展的空间竞争机制

运用生态学研究的相关原理和城市地理学的成果，对城市形成和发展过程中的竞争机制作了初步研究，指出竞争发生于城市发展的全过程和各相关尺度，是系统有序性目标的调控手段。对竞争机制的认识和利用，有益于城市空间结构的优化和发展战略的确定     

Random material variability effects on full-strength end-plate beam-to-column joints

In the seismic design of steel frames, beam-to-column joints are generally designed as full strength joints in order to avoid their engagement in the plastic range promoting the location of plastic hinges at the ends of the connected beams. In this paper, the reliability of the criteria to design full strength beam-to-column joints is investigated. In particular, in the first part of the work, starting from probabilistic analyses accounting for random material variability of connecting elements, the reliability of the design criteria suggested by codes is analyzed. Successively, on the basis of the obtained results, a new design criterion able to account for both the random material variability and the overstrength exhibited by the beam before the occurrence of local buckling is proposed.     

平疫结合的城市韧性社区建设与规划应对

作为疫情防控的基础单元,城市社区在面对突发公共卫生事件的冲击时,良好的应对能力对减少病毒传播、降低灾害损失至关重要。文章通过解读平疫结合的韧性社区内涵,从物质空间和社会空间层面构建了韧性社区评估框架,结合基层社区在新型冠状病毒肺炎疫情中的表现,剖析社区在疫情防控中存在的问题,并针对不足提出规划应对策略。期望为未来城市社区的韧性提升提供有益参考。     

“Mapping” Smart Cities

ABSTRACT

Smart cities are designed to use data to optimize resources, maintain sustainability, and improve people’s quality of life. While many urban technologies are employed to make cities “smart,” one constellation of technologies has been less examined in the academic literature—digital maps and the spatial data infrastructure. This paper is an attempt to systematically review the functions and evolution of digital maps and the spatial data infrastructure, with examples from Asia and beyond, in supporting and making smart cities possible. Based on the conceptual framework and empirical case studies, four major research directions of smart mapping are identified to better support smart city initiatives.     

营造充满活力的多样化空间形态——以呼和浩特托电工业园综合服务区修建性详细规划为例

在呼和浩特托电工业园综合服务区的规划设计中，通过用地功能的混合和多样化、人性化的道路交通系统、绿化水景的多样化、景观环境的多样化和富有特色的多样化居住形态，从而创造充满活力的多样化的空间形态，以满足人们生活多样化的需求.