城市策展设计策略解析——以德国柏林工业大学“台湾海峡区域城市设计”为例

城市策展设计策略是一种将实践与动态性研究相结合的城市设计技巧,它由其创始人——德国柏林工业大学建筑规划与环境学院可持续城市规划研究所Raoul Bunschoten教授于1993年率先理论性提出,并从2006年至今进行了大量教学与科研实践,从而得以不断完善。策略采用标准化表达语言赋予城市设计新思路,将设计策略"库"(即不同层面信息与案例集合)的元素重新应用于不同领域和地区;同时使用数字信息与手段动态控制规划并协调实践中的各个环节,为这一设计策略提供生命力。

Spatial-temporal Characteristics and Factors Influencing Commuting Activities of Middle-class Residents in Guangzhou City, China

The middle class in metropolitan Chinese cities has become an important social group. With the rapid development of urbanization and constant advancement of suburbanization, the middle class has increasingly come to influence city traffic. Research into middle-class commuting activities thus has practical significance for improving traffic congestion and reducing the commuting burden in metropolitan cities. Based on a dataset formed by 816 completed surveys, this paper analyzes the commuting mode, time and distance of middle-class residents in Guangzhou City using the descriptive statistical method. The results indicate that private cars are the main commuting mode, followed by public transport. Meanwhile, middle-class residents mainly undertake medium-short time and medium-short distance commuting. The study subsequently uses multilevel logistic regression and multiple linear regression models to analyze the factors that influence commuting mode choice, time and distance. The gender, age, number of family cars, housing source and jobs-housing balance are the most important factors influencing commuting mode choice; housing, population density, jobs-housing balance and commuting mode significantly affect commuting time; and transport accessibility, jobs-housing balance and commuting mode are the notable factors affecting commuting distance. Finally, this paper analyzes what is affecting the commuting activities of middle-class residents and determines the differences in commuting activity characteristics and influence factors between middle-class and ordinary residents. Policy suggestions to improve urban planning and urban management are also proposed.

Analyzing and Pondering on the Regulation of Urban Construction Land Expansion

Along with the economic development and the acceleration of urbanization,urban construction land expands rapidly in China,and has resulted in a series of socio-economic problems.This article summarized the major points of controlling the unchecked and rash expansion of construction land in the academic circle,and analyzed the problems of regulating the expansion of construction land from three aspects.First,this article analyzed the relationships between socio-economic development and urbanization from the historical viewpoints,and pointed out that the expansion of construction land is a historical phenomenon which will be surely appeared in the development of human race.Second,the authors utilized two-sector model to analyze the importance of urbanization in the socio-economic development from the academic angles.At last,the authors utilize four-quadrant model and bidrent curve model to analyze the influence that brought by the strict control of construction land expansion.Through analysis,this article drew some conclusions.First,the expansion of construction land is a phenomenon which will surely appear in the social development.It is impossible to accomplish the national modernization on the basis of dualistic structure between urban and rural areas.Second,under the function of rent gradient gap,strict control of construction land expansion will not only obtain the anticipated effects,but also cause a series of socio-economic problems,such as land-levying contradiction,the appearance of limited property right house,and being dependant on lease instead of expropriation.Third,unreasonable policies and governmental behaviors are the roots of the unchecked and rash expansion of urban construction land.Based on these conclusions,this article proposed that three transformations should be realized to regulate the unchecked and rash expansion of construction land:transfers from quantity regulation to quality regulation,from direct regulation to indirect regulation,and from single-measure regulation to multi-measures regulation.

Fertility Mediating Factors in Sub-Saharan Africa （SSA）： Macro-Level Cross Sectional Perspectives

The aim of this paper is to investigate the mediating factors of fertility levels and trends in Sub-Saharan African CSSA） countries. The major sources of data of the study are the 2001 and 2002 UNDP （United Nations Development Program）, covering 42 SSA countries. The selected antecedent variables of fertility levels and trends include： GDP per capita; female adult literacy rate; infant mortality rate; contraceptive prevalence rate; breastfeeding; access to health services; undernutrition; and level of urbanization. The main analytical techniques of the study include simple central tendency descriptive statistics and advanced multiple regression models. The outputs of the correlation matrix and regression models are shown to influence the levels and trends of fertility positively or negatively, increasing or decreasing fertility levels among the countries. But, contraceptive prevalence level appears to be relatively powerful at 5% significance level, relatively more decline with the level of urbanization and positively related with poverty level, which cumulatively gives rise to 5.9 total fertility rate per woman. Accordingly, with declining mortality and high fertility level, the era of rapid population growth in SSA countries has not yet been over with all its implications on sustainable development.

Study on the Mechanical Properties of Irregular Curved Steel Box Girder for City Viaduct

This paper deeply analyses the influence of different local tectonic on stress performance of spatial curved steel box Girder Bridge, using the finite element analysis software to establish space finite element model of this bridge, calculation and analysis were made on the bridge of the strength, stiffness. It has certain reference value for guiding engineering design, have a good foundation for the mechanical properties and stability of linear and nonlinear further study of curved steel box girder.

Modeling and Simulation for Urban Rail Traffic Problem Based on Cellular Automata

Based on the Nagel-Schreckenberg model, we propose a new cellular automata model to simulate the urban rail traffic flow under moving block system and present a new minimum instantaneous distance formula under pure moving block. We also analyze the characteristics of the urban rail traffic flow under the influence of train density, station dwell times, the length of train, and the train velocity. Train delays can be decreased effectively through flexible departure intervals according to the preceding train type before its departure. The results demonstrate that a suitable adjustment of the current train velocity based on the following train velocity can greatly shorten the minimum departure intervals and then increase the capacity of rail transit.