• Journal of Climate Change Research
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• v.7 no.3
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• pp.357-371
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• 2016

Buildings in the city acts as a cause of distorted wind direction, wind speed, causing the stagnation of the air flow. In the recent trend of climate change can not but consider the temperature rise of the urbanization. This study was aimed to analyze the thermal comfort of planetary boundary layer in different artificial constructions areas which has a direct impact on urban climate, and estimating the warming phenomena. Envi-met model was used to consider the urban structure associated with urban growth in order to precisely determine the impact of the building on the city weather condition. The analyzed values of thermal comfort index were temperature, wind speed, horizontal and vertical turbulent diffusivity. In particular, analysis of the PPD(Predicted Percentage of Dissatisfied) represents the human thermal comfort. In this study, by adjusting the arrangement and proportion of the top floor building in the urban it was found that the inflow of the fresh air and cooling can be derived low PPD. Vertical heat flux amount of the city caused by climate change was a factor to form a high potential temperature in the city and the accumulation of cold air does not appear near the surface. Based on this, to make the city effectively respond to climate change may require a long-term restructuring of urban spatial structure and density management.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.3
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• pp.46-55
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• 2003

This study aims to evaluate the Ulsan city residents' perception and satisfaction with open spaces and cityscape after consideration in the side of getting primary data for the city open spaces policy and Green Plan for Ulsan city. In this study, low data was gathered by questionnaires survey with stratified random sampling method. Questionnaires were designed by several sets of variables such as behavioral patterns, satisfactions for open spaces and user's demographic variables. Data were analyzed by descriptive statistics, cross-tabulation and regression analysis. The main results of this study can be summarized as follows : 1. In overage the residents were slightly satisfied with park open spaces. There were good and poor park open spaces. in the perceptions of citizens as follows : 'nearby mountain and open spaces', 'rail side green area' were high satisfactory, and 'riverside', 'green qualities' were low in satisfaction. 2. In overage the residents were slightly satisfied with cityscape. There were good and poor cityscape in the perceptions of citizens as follows : 'nearby forest in and open spaces', 'night scape of an urban center' were high satisfactory, and 'streetscape', 'appearances of high-rise buildings' were low in satisfaction. 3. As a results of regression analysis predictable variables for satisfaction with Park and Open spaces were : 'open spaces by the public', 'open spaces by neighbor', 'grande open spaces', 'open spaces of residence'. 4. As a results of regression analysis predictable variables for satisfaction with cityscape were : 'Central Business District(C.B.D) and nearby mountain and open spaces', 'residence and streetscape', 'riverside and park green open spaces'.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1301-1306
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• 2009

Recently, urban excavations are one of most frequent geotechnical work according to construction of a high rise building and subway. These kind of excavation affect to a adjacent ground or structure and it can trigger various severe accidents. Generally, the ground is closer to the excavation site, the deformation become larger. In this study, special ground settlement case due to adjacent ground excavation is presented and a cause of deformation is examined by various geotechnical exploration, lab-testing and numerical analysis.

• International Journal of High-Rise Buildings
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• v.6 no.4
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• pp.315-322
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• 2017

A modern and highly-sustainable addition to the skyline of Seoul, South Korea has been completed; the Federation of Korean Industries Headquarters (FKI). The signature saw-toothed exterior wall of the 245-meter tall tower and the contrasting smooth nature of the pipe-shell structured podium "egg" gives this project and site a unique identity in the city.

• International Journal of High-Rise Buildings
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• v.2 no.2
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• pp.115-121
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• 2013

The ventilation performance of a street in Bangkok, Thailand, was investigated by performing measurements and conducting a CFD analysis. We focused on a street that was covered by an elevated train station. It was shown that the ventilation efficiency varied drastically depending on the angle between the street and the wind direction. When the wind direction was parallel to the street, the elevated structure had a negative influence, which created higher pollutant concentrations than in locations without elevated structures. However, when the wind direction was perpendicular to the street, the pollutant concentrations in the two situations were similar. Using a CFD analysis and ventilation performance indexes, it was shown that the elevated structure directed the wind flow and enhanced the ventilation efficiency, which positively affected ventilation performance. These kinds of knowledge can lead us to optimize city planning including high-rise buildings with high ventilation efficiency.

• Journal of the Korea Institute of Building Construction
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• v.21 no.5
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• pp.483-493
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• 2021

Urban overcrowding has created an explosive supply and demand for high-rise buildings. High-rise buildings are contributing to enhancing the image of the city by serving as focal points, but due to the stack effect, malfunction of elevator doors, difficulties in opening and closing the doors and windows of the outer wall, smoke and odors spreading to the upper floors, noise, energy loss, fire and pollutants have been causing various unexpected problems such as rapid spread of fire. This study classified high-rise buildings according to their vertical zoning, analyzed the causes of and solutions to the stack effect, and derived design and construction methods. Through the initial plan to block the outside air and securing airtightness through precise construction, we sought ways to secure the airtightness inside and outside the building by actively blocking the airflow from the lower floors. In addition, the facility solution can be a measure to reduce the specific phenomena caused by the stack effect, but it should only be applied to the minimum extent because the potential for secondary damage is high. This study emphasized the need for systematic stack effect management by suggesting design and construction measures for each vertical zoning of the causes and countermeasures of the stack effect. It is expected that this study will be helpful not only for design and construction, but also for building maintenance.

• International Journal of High-Rise Buildings
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• v.1 no.2
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• pp.117-123
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• 2012

This paper discusses major strengths of tall buildings that distinguish them as sustainable solutions for the built environment. It sheds light on some of the key attributes of tall buildings as well as materials and technologies that could boost their performance environmentally, economically and technically as well as the natural habitats containing them. Tall buildings are portrait as major successful options for accommodating the ever increasing urban world population, with little negative impact on ecologies and environmental habitats worldwide. The role of tall buildings as 'vertical garden sub-cities' mitigating modern city problems of 'urban heat islands' and sprawling cities is explored. A few building examples as well as city developments are presented which represent the new generation of sustainable tall buildings that are setting trends for future projects incorporating innovations in materials and building systems and designs.

• International Journal of High-Rise Buildings
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• v.7 no.2
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• pp.95-109
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• 2018

Since the concept was first introduced in the 1970s, transit-oriented-development (TOD) has greatly expanded in East Asian cities such as Hong Kong. Rail stations are built together with clusters of residential-commercial towers and government services to form a new style of living - a "rail village." This paper examines the composition, scale, spatial form, organization and operation of several typical rail villages in Hong Kong. The cases range across those planned from the mid-1990s to 2015. Based on the analysis of the rail village composition, the paper derives a development ratio to indicate the density, effectiveness and efficiency of a rail village catchment area. The ratio provides a useful and direct figure for the comparison of different stations, cities and development modes.

• International Journal of High-Rise Buildings
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• v.12 no.1
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• pp.19-33
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• 2023

Air Rights techniques, including floor-area ratio (FAR) transfers, FAR bonuses, and FAR storage, have been widely applied among skyscraper constructions in New York City for profit maximization goals. Since 1916, air rights regulations in New York zoning system have been revised and improved over the years to cater the urban development needs of different periods, and they also result in typical skyscraper block typologies. This research firstly performed spatial overlay analysis to reveal the spatial correlation between skyscraper blocks and air rights application blocks; secondly, Spacematrix parameters and cluster analysis are applied to divide the skyscraper urban block of New York City into four categories. Compared with air rights application data, the research attempts to illustrate how various air rights techniques have acted on the formation and evolution of skyscraper block typologies in the pre-1916, 1916-1961, 1961-2010, and 2010-present periods respectively, in order to reveal the relationship between public policies and urban morphology in a broader sense and also provide references for policy making in future.

• International Journal of High-Rise Buildings
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• v.12 no.1
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• pp.49-61
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• 2023

The transit-oriented development (TOD) model can effectively help to solve urban problems and promote sustainable urban development. The United States and Japan are widely considered the earliest two countries to start TOD practices; however, the origins of TOD models in the two countries were different. The TOD practices in the two countries formed distinct characteristics, yet their differences have been underexplored. This study aims to grasp the characteristics of the TOD model in the two countries through a systematic comparative analysis of 10 typical cities in the United States and Japan that have adopted the TOD model. This paper compares the case cities' three key aspects of the TOD model: public transit system, spatial form, and land use, and summarizes the characteristics of TOD models in the two countries from a city-level perspective, to help deepen the global understanding of TOD.