• Journal of Korean Society of Environmental Engineers
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• v.31 no.7
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• pp.521-530
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• 2009

This study has been made to execute a research in order to lead the improvement of indoor air quality, examining the indoor ventilation characteristics by using a numerical analysis method. To this end an extensive parametric investigation are made according to various external flow variables such as main wind direction and wind speed by season, building layout design, and location of ventilators, etc. in Daedeok Techno Valley, one of large-scaled apartment in Daejeon. It is observed there was a significant difference of main wind direction between summer and winter. The main wind direction in summer was a south wind, and on the contrary the direction in winter is northnorthwest, which is similar to the average main wind direction for 10 years. One of the important calculation results is that the change of wind direction causes a significant effect on the apartment ventilation by the change of pressure difference around each complex of apartment. In case of favorable area of ventilation, the indoor ventilation rate can meet 0.7 ACH from the standard value only with natural ventilation. On the contrary, in other area the value was much lower than the standard value. If the calculation result applies to the design of layout apartment or placement of ventilators, it will be greatly helpful to the energy saving because it can be parallel with the natural ventilation to help securing ventilation rate, not much depending on the mechanical ventilation.

• Journal of Cadastre & Land InformatiX
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• v.53 no.2
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• pp.79-92
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• 2023

With a growing interest in the Han River Skyline, which greatly influences Seoul's image, careful consideration of the skyline form has become crucial in the redevelopment plans for apartment complexes along the Han River. The Seoul Metropolitan City government has lifted the height limitations for apartments along the Hang River to cultivate a vibrant skyline. However, traditional skyline analysis often overlooks specific attributes, limiting the provision of precise guidelines for Seoul's unique skyline plans. Despite advancements in Digital Twin technology, only some tools effectively manage urban skylines with preferred shapes. Hence, this study aims to make a substantial contribution to the advancement of a Digital Twin 3D modeling program capable of effectively managing urban skylines. This is achieved through the utilisation of Conjoint Analysis, which assesses the importance of each attribute in determining the preferred skyline shape. Focusing on Apgujeong apartment complexes along the Han River currently undergoing redevelopment or planned for redevelopment, the study analyses the preferred skyline shape to propose standards for the Digital Twin 3D modeling program development. It also suggests that Conjoint Analysis can be beneficial in this process.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.2
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• pp.53-65
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• 2012

This study was focused on removal efficiency of complex (or mixed) wastewater from agricultural and industrial plant for advanced treatments by HBR-II process, that was well known to be suitable to the treatment of livestock wastewater. The main purpose of this study was intended to evaluate the applicable feasibility of the HBR-II for revamping the present activated sludge process to the advanced one. And also, the settling study including the batch typed experimental column tests was performed to evaluate the coagulation stability of organic colloidal particles in wastewater. The mid-scale plant of HBR-II process between pilot and laboratory was used for this study. As F/M ratio remains constant in the range of 0.20~0.25 $BOD_5/Kg{\cdot}MLSS/Day$, the efficiency of biological treatment increased. It has been shown that the results of biodegradation study were, for removal efficiency(%), $BOD_5$ 98.4%, $COD_{Mn}$ 92.9%, SS 97.5%, T-N 91.3%, T-P 82.3%, respectively, which were relatively higher than other processes. From this study, HBR-II process would be well applied to the biological treatment of agricultural and industrial complex wastewater.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.1
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• pp.43-49
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• 2009

The number of registered vehicles increased to one million in 1985 and ten million in 1997, and the parking lots in multi-family housing complex that had been mainly constructed on the ground level began to be constructed in underground levels. Therefore, planting design in such complex were greatly changed. This study classifies the parking lots in multi-family housing complexes located in Cheongju into three categories: above-ground, mixture of above-ground and underground, and underground. The characteristics of planting design in each were then analyzed. The rate of parking per family increased by two or more in the type of mixture when compared to in the type of above-ground. As underground parking lots became dominant, the rate of parking per family increased to one car or more. The green area ratio did not change considerably when above-ground parking was combined with underground parking, but the green area per total floor space was reduced, which indicates the quality of green area became lower. Most of the parking lots in multi-family housing complexes since 2000 have been constructed underground, and the green area became larger. As for the species of trees used in planting design, trees that are vulnerable to damage by blight and harmful insects and may be repugnant have been reduced and replaced by trees whose shapes are beautiful and whose flowers and fruits can be appreciated, such as Chionanthus retusa, Malus floribunda, Styrax japonicus, Prunus mume, Lagerstroemia indica. Pine trees are variously planted with diversified standards, and, in particular, tall pine trees are being utilized as focal points. Herbaceous flowers began to be planted in underground parking lots constructed since 2000, and they are expected to be planted even more due to the appreciation of their flowers and their splendid appearance.

• Journal of Environmental Impact Assessment
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• v.29 no.4
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• pp.252-271
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• 2020

In this study, we investigated physical and chemical properties such as grain size, heavy metal pollution, magnetic properties, and their environmental impacts of road dusts (RD) collected from 14 sampling points in Daebul industrial Complex. Heavy metal concentrations in RD were in the order of Fe>Zn>Cu>Pb>Cr>Ni>As>Cd>Hg, and this pollution pattern was related to major industries and traffic activities in this area. The results of the correlation analysis between heavy metal elements and particle size in RD showed that Fe and all of analyzed heavy metals had a significant correlation with each other and metal concentrations had a significantly negative correlation (p<0.05). However, due to the input of large metal particles some heavy metal concentrations in the particle fraction of >1000 ㎛ were highest. Pollution load per unit area of this fraction was the highest among the grain size fractions. Cr, Ni, Cu, Zn, Cd, Pb levels in RD decreased and the levels of Cr, Ni, Cu, Zn, Cd, and Pb were reduced to 85 (As) -22 (Ni)% of the whole after removal of MFs fraction from RD. The mean heavy metal levels in the study area did not exceed the soil contamination guide value of Korea, indicating that heavy metal levels in RD were not a concern. However, at some sampling points, Zn concentrations were exceeded the soil contamination guide value for the 3rd areas of Korea and this result indicated that further studies of the impact of RD on the surrounding environment through re-suspension or non-point pollution, and of effective management methods are required.

• Journal of Korea Water Resources Association
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• v.46 no.3
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• pp.277-285
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• 2013

The purpose of this research is to evaluate the scenic value of the Gyungin Ara waterway in real estate prices. Apart from the multi-functionality such as transportation of passengers and freight, prevention of floods, and provision of leisure areas, the Ara waterway possesses a scenic function which offers people esthetic value through unique and beautiful scenery. This scenic function is an externality for apartment residents living nearby. The applied methodology for this research is the Hedonic Price Model (HPM) which creates a cause and effect model between real estate prices and attributes. Variables such as apartment sale prices, complex characteristics, location characteristics, timely characteristics have been deduced through data collected from a total of 4,207 households that have experienced actual transactions during the same period, all located within the scenic benefit boundaries of the waterway. Landscape variable has been derived from algorithm designed by a combination of digital map and Google Mapview. The scenic value of the waterway estimated through the application of HPM on these variables is 165,000 Won per area (pyeong). The regional asset enhancing effect caused by the landscape view of the waterway is estimated to be 89.1 billion won.

• Korean Chemical Engineering Research
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• v.58 no.3
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• pp.325-345
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• 2020

Determination of Best available technology (BAT) was suggested to reduce volatile organic compounds (VOCs) in a petrochemical industrial complex, by conducting human health risk, environmental, and economic assessment based on multimedia fugacity model. Fate and distribution of benzene, toluene, ethylbenzene, and xylene (BTEX) was predicted by the multimedia fugacity model, which represent VOCs emitted from the industrial complex in U-city. Media-integrated human health risk assessment and sensitivity analysis were conducted to predict the human health risk of BTEX and identify the critical variable which has adverse effects on human health. Besides, the environmental and economic assessment was conducted to determine the BAT for VOCs reduction. It is concluded that BTEX highly remained in soil media (60%, 61%, 64% and 63%), and xylene has remained as the highest proportion of BTEX in each environment media. From the candidates of BAT, the absorption was excluded due to its high human health risk. Moreover, it is identified that the half-life and exposure coefficient of each exposure route are highly correlated with human health risk by sensitivity analysis. In last, considering environmental and economic assessment, the regenerative thermal oxidation, the regenerative catalytic oxidation, the bio-filtration, the UV oxidation, and the activated carbon adsorption were determined as BAT for reducing VOCs in the petrochemical industrial complex. The suggested BAT determination methodology based on the media-integrated approach can contribute to the application of BAT into the workplace to efficiently manage the discharge facilities and operate an integrated environmental management system.

• The KIPS Transactions:PartA
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• v.15A no.6
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• pp.351-360
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• 2008

It seems reasonable to assume that the individualized learning means more than simple teaching-learning method, so the instructional method has attracted a fair amount of attention not only in classroom, but also in the field of a adult education, cooperate education, and so on. In order to have an effect on individualized learning, we need to analyze and measure the learner's characteristic. However it is difficult to represent in quantified form because the conception and category of learner's characteristic is various and extensive. Therefore, in this paper, we propose a quantification method of learner's characteristic, which is limited to learner's cognitive structure and style, and is represented in the light of connectionism, verify the validity. The learner's cognitive structure in this paper was represented, which simplified the learner's cognitive structure. Additionally, the cognitive style in this paper was limited to inertia of knowledge for learner's cognition.

• Journal of the Korean Regional Science Association
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• v.32 no.2
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• pp.15-29
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• 2016

Suburbs rural areas in the Capital region have been diversified by the influence of the Seoul and large cities for the last 10 years. This study aims to classify suburban rural areas and to analyze the differentiated characteristics of different types in order to propose more area-specific policy approach to suburban rural areas in the Capital region. Using the cluster analysis method, the suburban rural areas in the Capital region have been classified into four types; garden villages in rural areas, urbanization areas, agricultural-industrial mixed use areas, general rural areas. The result of this study shows that the four types of suburban rural areas are much differentiated one another in terms of internal characteristics and local dynamics and problems. In order to suburban rural sustainable development in the Capital region, the policy efforts should be address the area-specific problems and policy demand for each type of suburban rural areas.

• Korean Journal of Materials Research
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• v.11 no.3
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• pp.207-214
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• 2001

Silica glass is a core material for optical fiber in optical telecommunications, but its centrosymmetry eliminates the second order nonlinearity. But it is experimentally well known that the space charge polarization induces the Second Harmonic Generation (SHG) when a strong DC voltage is applied to silica glass for a long period of time with metal blocking electrodes. In this report, the results of a theoretical calculation of the nonlinear optical property caused by the space charge polarization, and a model of a numerical analysis to predict the small chance in nonlinear optical property as functions of time and space are provided. Assuming that amorphous silica is a solid state electrolyte and sodium ion is the only mobile charge carrier, 'Finite Difference Method' was employed for modeling of numerical analysis. The distributions of the concentration of sodium ion and electric field as functions of a normalized length of the specimen and a normalized applied voltage were simulated.