• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.6
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• pp.396-402
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• 2009

Recently many efforts have been carried out on the development of energy-efficient and environment-friendly systems in order to preserve natural environment and to reduce environmental loads in the branch of the urban planning and the building design. In this study, a mathematical method was developed and a numerical analysis was carried out with various parameters to provide substantial data for optimal design and operation of urban energy supply systems. Components of the system and their specifications, such as a co-generation system and other heating and cooling systems, could be obtained through this analysis for various resource and energy requirements in urban area. In this study, the system constituents and operating characteristics, and their economic performances such as the value of objective function, the amount of energy consumption were discussed for various load patterns and power load ratios. Also, it turns out that the optimal energy supply system can save energy by $10{\sim}20%$ in comparison with the conventional energy supply system.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.101-109
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• 1998

Recently, improvement of the quality of urban riverscape environment has been emphasized not only by landscape architectural field but also by various professionals in planning and ecology. Regarding to this current movement, the aim of this paper is to highlight major visual elements of riverscape axis as a case study of Shinchon River in Taegu City to suggest some basic guidelines for arranging riverscape in urban area. The study was mainly based on Repertory Grid Development method which was developed in Japan. The method is consist of three steps such as decision of element landscape in study area for slide photos, selection of evaluation items for interview and obstraction of proper evaluation factors. The major findings through this study are as follows; 1) The 12 major visual elements which possibly improve riverscape, based on abstraction of proper evaluation factors, are Dunchi, surface of the water,, equipment of river, buildings near riverside, river vertical and horizontal facilities like bridge, fine view, riverbed, water plant, naturalness, water's edge line, harmony and street trees by order. 2) Total numbers of adjective which describe 12 common factors are 25, such as clean, open, stable, quiet, comfortable, friendly, bright, natural etc. In addition, Dunchi was described 337 times by various adjectives, surface of the water was 200 times and arrangement of river was 146 times which is similar result with the order of 12 influential common factors. 3) Therefore, Dunchi, surface of the water and equipment of river are three most important factors which could create better riverscape. These three factors implies us how we supply good quality of urban river environment for the urban residents.

• Journal of Auto-vehicle Safety Association
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• v.13 no.4
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• pp.7-13
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• 2021

This paper presents an vulnerable road user (VRU) classification and tracking algorithm using vision and LiDAR sensor fusion method for urban autonomous driving. The classification and tracking for vulnerable road users such as pedestrian, bicycle, and motorcycle are essential for autonomous driving in complex urban environments. In this paper, a real-time object image detection algorithm called Yolo and object tracking algorithm from LiDAR point cloud are fused in the high level. The proposed algorithm consists of four parts. First, the object bounding boxes on the pixel coordinate, which is obtained from YOLO, are transformed into the local coordinate of subject vehicle using the homography matrix. Second, a LiDAR point cloud is clustered based on Euclidean distance and the clusters are associated using GNN. In addition, the states of clusters including position, heading angle, velocity and acceleration information are estimated using geometric model free approach (GMFA) in real-time. Finally, the each LiDAR track is matched with a vision track using angle information of transformed vision track and assigned a classification id. The proposed fusion algorithm is evaluated via real vehicle test in the urban environment.

• Asian Journal of Atmospheric Environment
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• v.8 no.1
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• pp.15-24
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• 2014

The capital city of Himalayan Country Nepal, Kathmandu Valley is surrounded by consecutive high mountains, which limits the air distribution and mixing effects significantly. It in turn generates steady air flow pattern over a year except in monsoon season. The air shed in the Valley is easily trapped by the surrounded mountains and the inversion layer formulated as the cap. The $PM_{10}$ concentration was noticeably higher than the standard level (120 ${\mu}g/m^3$) in urban and suburban area of Kathmandu valley for all seasons except monsoon period. The Valley area experiences similar wind patterns (W, WWS, and S) for a year but the Easterly wind prevails only during the monsoon period. There was low and calm wind blows during the winter season. Because of this air flow structure, the air emission from various sources is accumulated within the valley air, high level of air pollution is frequently recorded with other air polluted cities over the world. In this Valley area, brick kilns are recognized as the major air pollution source followed by vehicles. Mostly Bull Trench Kiln (BKT), Hoffman Kiln and Vertical Shaft Brick Kiln (VSBK) are in operation for brick firing in Kathmandu valley where the fuels such as crushed coal, saw dust, and natural gas are used for processing bricks in this study. Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts (TRACI) was used for screening and quantifying the potential impacts of air emission from firing fuels. The total Environmental Performance Score (EPS) was estimated and the EPS of coal was approximately 2.5 times higher than those of natural gas and saw dust. It is concluded that the crushed coal has more negative impact to the environment and human health than other fuel sources. Concerning the human health and environment point of view, alternative environment friendly firing fuel need to be used for brick industry in the kiln and the air pollution control devices also need to be applied for minimizing the air emissions from the kilns.

• Structural Engineering and Mechanics
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• v.39 no.2
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• pp.187-206
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• 2011

This paper uses dynamic computer simulation techniques to develop and apply a multi-criteria procedure using non-destructive vibration-based parameters for damage assessment in truss bridges. In addition to changes in natural frequencies, this procedure incorporates two parameters, namely the modal flexibility and the modal strain energy. Using the numerically simulated modal data obtained through finite element analysis of the healthy and damaged bridge models, algorithms based on modal flexibility and modal strain energy changes before and after damage are obtained and used as the indices for the assessment of structural health state. The application of the two proposed parameters to truss-type structures is limited in the literature. The proposed multi-criteria based damage assessment procedure is therefore developed and applied to truss bridges. The application of the approach is demonstrated through numerical simulation studies of a single-span simply supported truss bridge with eight damage scenarios corresponding to different types of deck and truss damage. Results show that the proposed multi-criteria method is effective in damage assessment in this type of bridge superstructure.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.967-972
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• 2009

The present urban redevelopment has caused many problems. The truth is that the improvement of residential environment in this country has resulted in high-rise apartment buildings of the same form, without regard for vestiges of previous residents and regional characteristics. If redevelopment should be continued in a proper way to improve the right to adequate housing, a new form of urban design will be required, solving existing problems. For this, the cultural and ecological elements of the redevelopment site to be conserved and developed should be found and designed. Consequently, this study focuses on the cases of domestic and overseas urban design that cultural and ecological elements have been applied to redevelopment, and suggests Hwamyeong-dong, a deteriorated area in Busan, to design from a cultural and ecological point of view.

• Resources Recycling
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• v.19 no.5
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• pp.13-24
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• 2010

To investigate the necessity and background of the metal recycling from urban mine resources, 4 bigger problems such as the limitation of the underground resources, consumption of the metal resources, contamination of environment and metal recycling business were reviewed. Waste management and recycling are the foremost issues facing Korea on its path to sustainable development in the 21st century. Especially, metal recycling from urban mines is the most urgent fact for global environment and resources conservation. In order to build a recycling-oriented society, it is necessary to develop the recycling technology, recycling practices and a recycling-oriented economic system.

• Journal of the Korean Institute of Rural Architecture
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• v.23 no.3
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• pp.9-18
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• 2021

This paper conducted a survey of residents and public officials for the projects to make smart-city plans of Geumsan-gun. In introduction, several domestic and foreign cases related to smart-city projects were Investigated. To initiate the smart-city project of Geumsan-gun, the local status of Geumsan-gun was investigated regarding various aspects of natural, social, urban environment and smart-city facilities. The results of this survey are as follows: Overall, more than half of survey respondents said they had satisfaction of their housing quality. Several problems in their residence areas, such as insufficient welfare systems, shortage of parking spaces, industrial infrastructure, were reported. Meanwhile, the survey result indicated that tourism and leisure facilities, health care support systems, industries promote the economy and job market of the area. An interview with public official is also important to select the relevant meaningful projects and regional issues. Three models for each spatial unit were proposed in Geumsan-gun based on the natural, agricultural, and geographical environment. In result, the three smart-city models are categorized as urban type(large area), complex city type(medium area), and smart village type(small area)

• Journal of the Korean housing association
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• v.23 no.5
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• pp.87-94
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• 2012

The primary purposes of this study are to suggest a medium-sized regeneration project which includes the excluded small sites near existing regeneration site, to identify urban improvement type which fits local conditions, and to suggest proper regeneration strategies for the improvement type. Main findings of this study are follows. First, the size of the living environment improvement project in urban area should be larger than 3ha and government's incentives are required for parcel merges to make the medium-size project site. Second, independent type of urban regeneration project should consider local characteristics while center-spread type of urban regeneration project should build a center by providing neighborhood facilities and proper housings. Third, urban regeneration project should be able to utilize local assets, such as cultural heritages, natural landscapes, transportation facilities. Fourth, standards for public support should be prepared to improve local competitiveness. Last, further studies are required for urban regeneration system improvement.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.249-252
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• 2005

저주파수에서 유전상수 측정시 100kHz 이하의 주파수 영역에서는 전극분극효과가 발생하므로 100kHz이상의 주파수에서 유전상수가 평가되어야 한다. 유전상수는 쌍극자모멘트의 수에 비례하기 때문에 흙의 유전상수는 체적함수비에 따른 선형적인 증가경향을 나타내었다. 용액에 이온성분이 존재하는 경우에는 수화작용에 의한 물분자의 배향분극 발현의 감소로 인하여 유전상수가 감소한다. 흙과 중금속 혼합시료의 경우 함수비가 큰 시료에서는 용액의 유전특성이 발현되지만, 함수비가 작은 경우에는 공간전하분극의 영향으로 유전상수가 10-20%정도 증가하는 경향을 나타내었다. 현장에서의 정확한 오염도 평가를 위해서는 토양의 함수비에 대한 평가가 반드시 수행되어야 한다.