• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.4
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• pp.63-80
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• 2022

As a technology to analyze and predict an issue has been developed by constructing real space into virtual space, it is becoming more important to acquire precise spatial information in complex cities. In this study, images were acquired using an unmanned aerial vehicle for urban area with complex landscapes, and land cover classification was performed object-based image analysis and semantic segmentation techniques, which were image classification technique suitable for high-resolution imagery. In addition, based on the imagery collected at the same time, the replicability of land cover classification of each artificial intelligence (AI) model was examined for areas that AI model did not learn. When the AI models are trained on the training site, the land cover classification accuracy is analyzed to be 89.3% for OBIA-RF, 85.0% for OBIA-DNN, and 95.3% for U-Net. When the AI models are applied to the replicability assessment site to evaluate replicability, the accuracy of OBIA-RF decreased by 7%, OBIA-DNN by 2.1% and U-Net by 2.3%. It is found that U-Net, which considers both morphological and spectroscopic characteristics, performs well in land cover classification accuracy and replicability evaluation. As precise spatial information becomes important, the results of this study are expected to contribute to urban environment research as a basic data generation method.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.6
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• pp.371-384
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• 2021

Underground space, especially very-deep tunnel development in urban area, is a good alternative to solve the problem of insufficient ground space, and the need for underground space development is steadily increasing. However, due to the complex and time-consuming nature of design and construction, public conflicts related to the deep tunnel project are getting aggravating and more complex. In addition, since the public budget is mainly invested, when civil complaints arise, they often respond passively, resulting in amplification of conflicts or prolonging the deadlock in many cases. In this study, by analyzing the progress of major conflicts related to the construction of very-deep tunnels in urban area, the causes of conflicts, factors prolonging conflicts, and solutions are reviewed. Through a survey targeting ordinary citizens and tunnel experts, thoughts about the deep tunnel construction and major conflict factors were analyzed, and suggestions for minimizing conflicts were presented. The results of this study can be used to prepare alternatives such as various public involvement measures and improvement of project procedures to form a civic consensus on the construction of very-deep tunnels, and to prepare measures to improve prejudice against very-deep tunnels.

• International Journal of High-Rise Buildings
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• v.5 no.1
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• pp.13-20
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• 2016

Today's architecture can be best understood only through the recognition of pluralism, and, as is true of other building types, multiple design directions are prevalent for tall buildings. This contemporary design trend has produced many complex-shaped tall buildings, such as twisted, tilted and tapered form towers. Among many different structural systems developed for tall buildings, the outrigger system, with its inherent structural efficiency and flexibility in façade design, is widely used for contemporary tall buildings. This paper studies structural performance of outrigger systems employed for complex-shaped tall buildings. Twisted, tilted and tapered tall buildings are designed with outrigger structures, and their structural performance is investigated. For the twisted outrigger study, the buildings are twisted up to 3 degrees per floor. In the tilted outrigger study, the angles of tilting range from 0 to 13 degrees. The impact of eccentricity is investigated for gravity as well as lateral loads in tilted towers. In the study of tapered outrigger structures, the angles of tapering range from 0 to 3 degrees. Parametric structural models are generated using appropriate computer programs for these studies, and the models are exported to structural engineering software for design and analyses.

• Journal of Environmental Science International
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• v.13 no.3
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• pp.205-214
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• 2004

This study focuses on the measurement of airborne Volatile Organic Compounds (VOCs) in the Kumi electronic industrial complex during the time periods of August and September, 2002 and January and February, 2003. This study was based on the US-EPA method TO-14 while the VOCs were analyzed with GC/MSD. The toluene level revealed high concentration at all measurement sites. The areal rank of average concentrations of VOCs is as follows: industry1 > industry2 > urban > middle > residential. Concentrations of VOCs in Kumi electronic industrial ones were generally higher than at Yeochon and Ulsan industrial complexes. Dichloromethane and trichloroethylene, which are used as a cleaner in the process of electronic industries, were observed 4 to 8 times higher than those of other areas. Among the aromatic compounds, toluene showed the highest level, while the concentrations of dichloromethane and trichloroethylene were higher than those of other halogen compounds. In Kumi, toluene, trichloroethylene, and dichloromethane were confirmed as the major compounds of VOCs by this research.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.4
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• pp.430-439
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• 2007

The objective of this work is the air quality modeling according to the practical roughness length using the building information as surface boundary conditions. As accurate wind and temperature field are required to produce realistic urban air quality modeling, comparative simulations by various roughness length are discussed. The prognostic meteorological fields and air quality field over complex areas of Seoul, Korea are generated by the PSU/NCAR mesoscale model (MM5) and the Third Generation Community Multi-scale Air Quality Modeling System (Models-3/CMAQ), respectively. The simulated $O_3$ concentration on complex terrain and their interactions with the weak synoptic flow had relatively strong effects by the roughness length. A comparison of the three meteorological fields of respective roughness length reveals substantial localized differences in surface temperature and wind folds. Under these conditions, the ascended mixing height and weakened wind speed at night which induced the stable boundary stronger, and the difference of simulated $O_3$ concentration is $2{\sim}6\;ppb$.

• Architectural research
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• v.19 no.3
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• pp.53-61
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• 2017

This study aims to understand and analyze the social recognition and debate shown during the progress of the Asian Culture Complex (ACC) public project as well as the environmental evaluation performed by provincial community members. A 30-question survey based on a Likert scale was conducted with 150 experts. The study showed, first, that despite controversies over landmarks and historical locations, the quality of the architect's first draft was considered fairly high. However, vibrant landmarks were greatly desired. Furthermore, respondents reported conflicting recognitions of the same concept, which were defined differently depending on the terms and concepts used by the architect. Second, historical locations were considered important. The architects' final design was modified based on quality and in response to social pressure, resulting in the partial retention of the provincial government annex building. Although the first draft was considered to be of high quality, the modified plan was considered even better than the original design, revealing the 2-fold characteristics of the identical phenomenon in the environmental evaluation. Third, many groups held opinions that were balanced between the architects' originality and the value of community-based recognition; hence, the social inclination and evaluation of the project differed across the public.

• International Journal of High-Rise Buildings
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• v.5 no.4
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• pp.243-250
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• 2016

Today's architectural design trend based on the recognition of pluralism has led to multiple design directions for all building types including tall buildings. This contemporary design trend has produced many complex-shaped tall buildings, such as twisted, tilted, tapered and freeform towers. Among many different structural systems developed for tall buildings, the diagrid system, with its powerful structural rationale and distinguished aesthetic potential, is one of the most widely used systems for today's tall buildings. This paper studies structural performance of diagrid systems employed for complex-shaped tall buildings. Twisted, tilted, tapered and freeform tall buildings are designed with diagrid structures, and their structural performances are investigated. For the twisted diagrid study, the buildings are twisted up to 3 degrees per floor. In the tilted diagrid study, the angles of tilting range from 0 to 13 degrees. The impact of eccentricity is investigated for gravity as well as lateral loads in tilted towers. In the study of tapered diagrid structures, the angles of tapering range from 0 to 3 degrees. In the study of freeform diagrid structures, lateral stiffness of freeform diagrids is evaluated depending on the degree of fluctuation of free form. The freeform floor plans fluctuate from plus/minus 1.5 meter to plus/minus 4.5 meter boundaries of the original square floor plan. Parametric structural models are generated using appropriate computer programs and the models are exported to structural engineering software for design, analyses and comparative studies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.5971-5978
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• 2013

The aim of the study is to suggest the development type and the land-use model of smart green multi complexes focused on the lesson for future smart green complex in Korea. For the study, the concept and the development aspects are reviewed as a theoretical research and the development types of smart green multi complexes are surveyed based on its functional distribution. The types of multi-complexes are classified in three categories of small city, neighborhood and small housing estate regarding its size. As a result of the research, the land-use model of smart green multi complexes according to its types are suggested under consideration of Korean situation.

• Land and Housing Review
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• v.5 no.4
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• pp.271-279
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• 2014

Most CPTED have currently applied to newly developing apartment complexes. but developed apartment complexes are relatively vulnerable to crime due to lack of CPTED considerations. This study has examined both crime prevention preferences space and facilities considering the cost of CPTED. This study suggests plans of the CPTED application to the developed apartment complex without changing existing physical environment. The entrance of apartment complexes, underground parking lots, parks and rest areas, elevators, stairs and aisle in side of the buildings should be given top priority. The next are pedestrians roads, fences, main entrance on the first floor. Lastly, shopping store facilities and the ground parking lots are among the last ones.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.896-901
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• 2009

A Soil Nail is a structural element which provides load-transfer to the ground in excavation reinforcement applications. The nail may simply consist of a steel tendon, but most commonly the tendon is encapsulated in a cement grouted body to provide corrosion protection and improved load- transfer to the ground. For temporary excavation support in a congested urban area, the steel bar of Soil Nails should be removed to get permission of the private land to install Soil Nails. Several removable nail systems were developed and evaluated by pull-out load tests. The Soil Nail pull-out tests were performed on five nails installed in soft and hard rock at a 00 housing-redevelopment area in seoul. Two nails are plastic socket type and two are complex socket type mixed steel and plastic. The nail was 0.1mm in diameter, 4m long. In this study verification tests, and steel bar removing tests of plastic socket type nails and complex socket type nails were performed and presented.