Observing the rapid urban expansions and numerous infrastructure developments in the East-Asian context, many cities are suffering the urban heat island (UHI) effect and its associated environmental and social challenges. Moreover, the lack of sufficient attention to the application of effective heat mitigation strategies in current urban development in these cities can drastically intensify the eventual impacts of UHI. Therefore, many governmental sectors and policy makers have been implementing operative solutions for cooling cities. Nevertheless, this study argues that in Kuala Lumpur, despite the growing attention to this matter, there is still a need for more rigorous consideration by the architecture, engineering and construction (AEC) professionals as well as more scholarly studies to reflect sustainable solutions to the UHI effect. As a result, today, some of the dense urban areas in Kuala Lumpur are characterized with the use of thermally massive building materials, urban surfaces with low albedo, complex urban morphology, waste heat, and low density of vegetation. On the other hand, recent studies demonstrate that there has been a rapidly increasing interest in studies related to UHI in other East Asian regions such as Singapore and Hong Kong. Hence, this study develops a comparative analysis to provide a state-of-the-art review of the recent attempts towards mitigating the UHI effect in Kuala Lumpur, Singapore, and Hong Kong. Among several available UHI mitigation strategies, this study is limited to the analysis of the environmental impacts of urban vegetation (green roofs, green facades, vertical greeneries and green pavements). Findings reveal that in general, urban greening can significantly mitigate the UHI intensity, both directly and indirectly, resulting in the decrease of global air temperature and mean radiant temperature up to 4 ˚C and 4.5 ˚C respectively. Overall, the study develops new practical guidelines, discusses the public benefits and elaborates on the future directions of UHI studies.

Abstract. The vitality and viability of open spaces in urban neighborhoods, particularly in high-density residential areas with limited buildable land, have become extremely complex phenomenon. Researchers and designers are seeking the standard of designed environment to successfully meet the human needs and desires. In order to reach this goal, limited studies have been implemented to bridge the gap between research and design and consequently improve the physical and social qualities of open spaces. This paper examines the two specific features of open space -accessibility, social interactions -which contribute significantly to both the vitality and viability with a view to provide an understanding of the relative importance of these elements from users' perceptions and satisfaction. The methods involve quantitative research with questionnaire-based survey, and case study to evaluate residents' perceptions. The research scope is a highdensity residential condominium in Kuala Lumpur where the rapid transformation of urban elements in city center has negative impacts on basic qualities of open spaces. The result is a framework for understanding the relative priority of the different elements (variables) for users which vary depending on the location of the residential block they live in; in particular its proximity to the open space. The study concludes with recommendations for how the most valuable elements can be better harnessed in order to promote the satisfaction with open spaces.