Regional consortia and transaction costs for sanitation services in Brazil

Studies on public cooperation usually focus on its impact on the service costs experienced by service providers. However, engagement in public cooperation in service provision often seeks other outcomes, like service coverage (measured by the population served) rather than simply minimizing service expenditure. Moreover, public cooperation by local governments, as either ‘providers’ or owners, generates transaction costs arising from negotiation, monitoring, agency costs and the enforcement of cooperative agreements. However, to date, little empirical effort has been directed at determining the impact of transaction costs on service provision owners and service outcomes. This paper addresses this gap in the empirical literature by examining the relationship between cooperative agreements between Brazilian municipalities for water and wastewater provision and service coverage in the light of transaction costs. We find that transaction costs are higher for cooperative providers due primarily to low service coverage levels, especially in sewage services that demand high investment in assets with high specificity. However, lower expenditures may occur after initial up-front investment.     

Critical conditions for onset of mould growth under varying climate conditions

A performance-based service life design format based on climatic exposure on one hand and “resistance” of materials against mould growth on the other hand, is presented in this paper. A limit state for onset of mould growth is defined as the occurrence of traces of mould observed by microscopy. A dose–response model is proposed by which onset of mould growth can be predicted for an arbitrary climate history of combined relative humidity ? and temperature T. The model is calibrated and verified against a comprehensive set of experimental data published by Viitanen et al. [Viitanen H, Ritschkoff A-C. Mould growth in pine and spruce sapwood in relation to air humidity and temperature. Uppsala: Swedish University of Agricultural Sciences, Department of Forest Products; 1991. Report No. 221, 49 p.; Viitanen H. Modelling the time factor in the development of mould fungi – effect of critical humidity and temperature conditions in pine and spruce sapwood. Holzforschung 1997;51(1):6–14; Viitanen H. Modelling the time factor in the development of brown rot decay in pine and spruce sapwood – the effect of critical humidity and temperature conditions. Holzforschung 1997;51(2):99–106; Viitanen H, Bjurman J. Mould growth on wood under fluctuating humidity conditions. Material und Organismen 1995;29(1):27–46] describing mould development on spruce and pine sapwood as a function of climatic exposure. The model is applied to predict time to onset of mould growth under natural outdoor climate (under shelter) as well as mould development in building attics and in crawl space foundations. The predicted response shows reasonable agreement with experimental observations and proven experience, although biological processes of this type display great variability. The results show that a generally applicable, quantitative model can be used as a powerful tool for moisture safe design in practice. The model is designed to facilitate continuous improvement of prediction capability by further laboratory testing of various materials under specified climate conditions. In combination with currently available building physics software the model is suitable for moisture safe design of wood-based components in the building envelope.     

Enhancement of stack ventilation in hot and humid climate using a combination of roof solar collector and vertical stack

In the hot and humid climate, stack ventilation is inefficient due to small temperature difference between the inside and outside of naturally ventilated buildings. Hence, solar induced ventilation is a feasible alternative in enhancing the stack ventilation. This paper aims to investigate the effectiveness of a proposed solar induced ventilation strategy, which combines a roof solar collector and a vertical stack, in enhancing the stack ventilation performance in the hot and humid climate. The methodology selected for the investigation is physical experimental modelling which was carried out in the actual environment. The results are presented and discussed in terms of two performance variables: air temperature and air velocity. The findings indicate that the proposed strategy is able to enhance the stack ventilation, both in semi-clear sky and overcast sky conditions. The highest air temperature difference between the air inside the stack and the ambient air (T_i−T_o) is achieved in the semi-clear sky condition, which is about 9.9 °C (45.8 °C–35.9 °C). Meanwhile, in the overcast sky condition, the highest air temperature difference (T_i−T_o) is 6.2 °C (39.3 °C–33.1 °C). The experimental results also indicate good agreement with the theoretical results for the glass temperature, the air temperature in the roof solar collector’s channel and the absorber temperature. The findings also show that wind has significant effect to the induced air velocity by the proposed strategy.     

WUDAPT项目：城市形式与功能信息的众包解决方案及其应用

面对全球城市气候研究中的数据鸿沟,一个城市气候领域的先锋研究小组提出了WUDAPT项目以克服获取城市数据的障碍。文章基于“众包”理念,从城市形式与功能信息收集的视角,介绍了WUDAPT项目的概念和数据分级,分析了城市尺度（0级）、街区与建筑尺度（1、2级）的数据收集与应用的研究进展。文章指出WUDAPT将促进基于城市气候视角的城市形态研究方法的重大转变,并探讨了其在气候敏感型城市设计与规划中的应用潜力。     

河谷气候影响下的生态城市形态浅析 ——以重庆市奉节县整体城市设计为例

古往今来,气候特征对人类历史上 各种文明的产生和发展发挥着不同程度的作 用。虽然现代文明已经发展到可以抵御部分 气候带来的灾害,但是在目前所倡导的城市双 修、节能减排、绿色宜居,建设低碳生态城市 大背景下,通过城市的空间形态充分利用自然 气候带来的益处,减少不良气候带来的危害, 从而达到生态宜居,成为了城市建设的最终目 的。山地城市地形地貌复杂、生态环境敏感、 气候多变,在山地气候研究中又以河谷气候变 化最为复杂,河谷城市形态受气候及其它因素 影响与平原城市相比也有很大的不同。因此 本文选取具有典型河谷特征地形的奉节县为 例,研究通过城市形态利用较为复杂的局地 气候,最终达到建设生态城镇的目的。     

城市建筑与园林景观

介绍了现代城市中,园林景观与建筑物的功能、风格及空间布局之间的相互影响,主要从园林植物的装饰作用、对空气的净化作用、局部小气候的改善等方面阐述了园林对建筑物的影响。     

英格兰“地方发展框架”(LDF)及其启示

《规划与强制收购法2004》实施以来,英格兰的规划体系发生了根本性的变革。“地方发展框架”就是新体系下的一个新事物。本文在对英进行全面引介的基础上,探讨了对我国地方层面规划的启示。     

Metabolism and Morphology

Architecture is on the cusp of systemic change, driven by the dynamics of climate and economy, of new technologies and new means of production. There is a growing interest in the dynamics of fluidity, in networks and in the new topologies of surfaces and soft boundaries. This is part of a general cultural response to the contemporary reconfiguration of the concept of ‘nature’ within the discourse of architecture; a change from metaphor to model, from ‘nature’ as a source of formal inspiration to ‘nature’ as a mine of interrelated dynamic processes that are available for analysis and digital simulation. Michael Weinstock presents an account of the dynamics of natural metabolisms, and suggests an agenda for the development of metabolic morphologies of buildings and cities. Copyright © 2008 John Wiley & Sons, Ltd.     

生态环境和地域气候与现代建筑设计

分析了现代社会面临的环境问题,并对现代建筑的消极气候观进行了介绍,简单探讨了气候、地域与建筑之间的关系,同时对生态技术应用于建筑设计中的两种表现类型进行了阐述,以针对不同的地域气候设计出合理的建筑作品。     

本土营造——西北地区低碳生态乡镇的低技术策略

针对当前我国低碳生态城镇实践过分依赖“高技术、高投入”而难以实施的问题,结合西北地区乡镇发展的现实困境,本文提出西北地区乡镇低碳生态的理想路径为：探索一条具有地域适宜性的”低技术”策略,进而通过对西北地区乡镇碳排放特征的分析,提出加强对乡镇建设性碳排放的控制是西北地区乡镇实现低碳生态目标的关键。最后结合西北地区乡镇的地域特质,依托西安建筑科技大学在地域生态建筑与现代生土材料科学等领域的研究基础,提出：本土营造是降低乡镇建设性碳排放的有效途径,并提出其在规划与管理中的推广、应用策略。