Urban spatial structure,agglomeration economies,and economic growth in Barcelona: An intra‐metropolitan perspective*

This paper presents an intra‐metropolitan approach to analyse the impact of urban spatial structure on local economic growth. Focusing on the Barcelona metropolitan region (BMR) between 1986 and 2001, we estimate a municipal employment growth model in which dynamic agglomeration economies related to urban spatial structure are considered using distance to employment centres, to assess metropolitan effects, and distance‐weighted variables, to measure neighbourhood effects. The results obtained show the existence of neighbourhood specialization economies and metropolitan urbanization‐localization economies fostering local growth. All of this leads to the paper's main conclusion: urban spatial structure is important for economic growth in an intra‐metropolitan context.     

Cyberspace and physical space in an urban economy

In this article I construct a general equilibrium urban model with cyberspace and physical space. In cyberspace, there is a virtual production sector and it produces virtual goods. On the other hand, in physical space, a physical production sector is located in the CBD and it produces physical goods. The behaviour of home and office workers is considered in a Solow and Vickrey type linear city. I derive the market equilibrium of the city by numerical simulation using specific utility and production functions. The land use pattern and the time allocation of the workers are shown. I also show the spatial structure of the telecommunications and transportation networks. Received: 1 November 1998 / Accepted: 20 August 1999     

R&D competition in a spatial model with technical risk*

Abstract. In this paper, we introduce stochastic R&D into a Hotelling model with two duopolists. With an emphasis on the interaction between firms' R&D decision and location choice, we compare socially and privately optimal locations and levels of R&D. We show that, depending on R&D cost and the degree of technical risk, equilibrium location varies from minimum differentiation to maximum differentiation. From a welfare perspective, the equilibrium distance between the two firms could be either closer, farther or socially best. Moreover, depending on cost structure, firms' R&D expenditures could be either higher, lower or socially optimal, from a welfare viewpoint.     

夏热冬暖地区某开敞式大空间建筑的节能改造技术分析

为了探讨夏热冬暖地区开敞式大空间建筑的节能改造措施,以广州市某实际工程为例,应用Fluent软件,对自然通风、置换通风、遮阳、屋顶淋水降温的节能效果进行了定性分析,并应用DeST软件模拟了全年能耗。分析了自然通风与空调系统联合工作时的室内温度和速度场,并给出了室内温湿度的实测数据。结果表明:在该工程中,自然通风、置换通风、遮阳挡板和屋面淋水技术可明显改善室内热环境,同时降低建筑能耗;下沉式地面有利于增强室内置换通风效果;通过采用被动节能技术合理设计后,建筑节能率达61.9%。