• Corrosion Science and Technology
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• v.16 no.5
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• pp.235-240
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• 2017

Regional cathodic protection has significant impact on pipeline integrity management. After risk analyses of a newly built gas distribution station constructed in an area with large dwelling density, risk score was high because of potential threat caused by galvanic corrosion. Except reinforced steel in concrete, there are four kinds of metal buried under earth: carbon steel, galvanized flat steel, zinc rod and graphite module. To protect buried pipeline from external corrosion, design and construction of regional cathodic protection was proposed. Current density was measured with potential using potential dynamic test and boundary element method (BEM) was used to calculate current requirement and optimize best anode placement during design. From our calculation on the potential, optimized conditions for this area were that an applied current was 3A and anode was placed at 40 meters deep from the soil surface. It results in potential range between $-1.128V_{CSE}$ and $-0.863V_{CSE}$, meeting the $-0.85V_{CSE}$ criterion and the $-1.2V_{CSE}$ criterion that no potential was more negative than $-1.2V_{CSE}$ to cause hydrogen evolution at defects in coating of the pipeline.

• Korean System Dynamics Review
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• v.7 no.1
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• pp.147-172
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• 2006

With the purpose of long-range planning toward local/regional sustainable development, it is desired to avoid unconditional industrialization and expansion and to build an eco-oriented development strategy considering site-specific characteristics of the environment. This paper thus aims at the elaboration of a system dynamics model of a locality/region so as to understand inherent dynamics of sustainable development and to assess the effectiveness of such an eco-oriented strategy. The model thus consists of several positive and negative feedback loops that accelerate or restrict local/regional economic growth within a system boundary incorporating the environment, economy, and society. The model is moreover applied to the assessment of the effectiveness of the development plan recently established in Damyang in JeollaNamdo, Korea. It is regarded in this case to be effective for population immigration and economic prosperity to give priority to restore the bamboo ecosystem and nourish a series of eco-friendly industries based on the bamboo items developed recently. It is also to be positive to sustainable development since it enables to maintain high quality of the environment from the outset of their development steps.

• Journal of the Korean association of regional geographers
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• v.19 no.1
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• pp.147-161
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• 2013

This paper aims to examine the background, process, and characteristics of the territorial reform of local governments in West Germany (the Federal Republic of Germany) in the 1960s and 70s. During this period the territorial structure and function of municipality (Gemeinde), county (Kreis) and county-free town (Kreisfreie Stadt) as local governments were fundamentally reformed. The territorial reform of local governments paid special attention to merge the small-sized municipalities and to create the joint authorities in order to build the system of central localities. There had been criticism on the uniform boundary delimitation, confusion of regional identity, erosion of local autonomy and emphasis on the regional planning. But the territorial reform of the period has contributed to improve the performance of public administration and to strengthen the service delivery and planning capacity.

• Journal of the Korea Society of Computer and Information
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• v.13 no.1
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• pp.75-80
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• 2008

This paper proposes a method to detect scene change using global decision tree that extract boundary cut that have width of big change that happen by camera brake from difference value of frames. First, calculate frame difference value through regional X2-histogram and normalization, next, calculate distance between difference value using normalization. Shot boundary detection is performed by compare global threshold distance with distance value for two adjacent frames that calculating global threshold distance based on distance between calculated difference value. Global decision tree proposed this paper can detect easily sudden scene change such as motion from object or camera and flashlight.

• Journal of the Korean Society for Heat Treatment
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• v.26 no.3
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• pp.105-112
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• 2013

The microstructural changes of Fe-20Mn-12Cr-1Cu alloy have been studied during high temperature gas nitriding (HTGN) at the range of $1000^{\circ}C{\sim}1150^{\circ}C$ in an atmosphere of nitrogen gas. The mixed microstructure of austenite and ${\varepsilon}$-martensite of as-received alloy was changed to austenite single phase after HTGN treatment at the nitrogen-permeated surface layer, however the interior region that was not affected nitrogen permeation remained the structure of austenite and ${\varepsilon}$-martensite. With raising the HTGN treatment temperature, the concentration and permeation depth of nitrogen, which is known as the austenite stabilizing element, were increased. Accordingly, the depth of austenite single phase region was increased. The outmost surface of HTGN treated alloy at $1000^{\circ}C$ appeared Cr nitride. And this was in good agreement with the thermodynamically calculated phase diagram. The grain growth was delayed after HTGN treatment temperature ranges of $1000^{\circ}C{\sim}1100^{\circ}C$ due to the grain boundary precipitates. For the HTGN treatment temperature of $1150^{\circ}C$, the fine grain region was shown at the near surface due to the grain boundary precipitates, however, owing to the depletion of grain boundary precipitates, coarse grain was appeared at the depth far from the surface. This depletion may come from the strong affinity between nitrogen and substitutional element of Al and Ti leading the diffusion of these elements from interior to surface. Because of the nitrogen dissolution at the nitrogen-permeated surface layer by HTGN treatment, the surface hardness was increased above 150 Hv compared to the interior region that was consisted with the mixed microstructure of austenite and ${\varepsilon}$-martensite.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.2
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• pp.186-198
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• 2013

The present work is an attempt to improve the performance of a regional air quality model by means of liking it with a global chemistry transport model. The global chemical transport model of GEOS-Chem is used to provide BC (Boundary Condition)s which reflect temporal and spatial variations at boundaries of regional chemical transport model of CMAQ over East Asia. First, GEOS-Chem outputs are evaluated by comparing predicted concentrations with observed monthly data of gas phase species and secondary inorganic aerosols from EANET (Acid Deposition Monitoring Network in East Asia) sites. The results show that predicted PM10 concentrations are in good agreement with the observations. This implies that GEOS-Chem outputs could be used to provide BCs to CMAQ. Simulated daily and monthly mean PM10 concentrations of CMAQ with the linkage of GEOS-Chem's BCs and constant BCs are then evaluated by comparing predicted concentrations with observations at API (Air Pollution Index) sites in China as well as EANET sites in Korea. CMAQ with the GEOS-Chem outputs improves model simulation in depicting observed PM10 concentrations comparing with those with constant BCs. It is also found that influence of aerosol species are largely dependent on the BCs over East Asia and Korea. Mean biases between simulated versus observed daily and monthly mean concentrations of PM10 with the GEOS-chem were improved by 1~8 ${\mu}g/m^3$ in China region, 3.26 ${\mu}g/m^3$ in Korea.

• Journal of architectural history
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• v.13 no.3
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• pp.85-95
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• 2004

Through 16-17th century, Neo-Confucianism was accepted and extended to Chosun Dynasty. The architecture of the Taegae school made buildings of Yongnam area rich by adding the regional characteristics based on Taegae's thought of architecture. The following is the architectural characteristics of the academic clique around Sangju. Transformation such as separation and combination of the Jeongsa space by function, lifted floor type reflecting local feature or high platform was appeared, and the architectural characteristics of the Taegae school, that is, a small scale, a moderate figure, a type of side-attached floor, landscape, were still maintained at the same time. The characteristics of the Taegae school and regional figure of Sangju were well joined. The upper class houses, Seodang, Jeongsa and Seowon, built by Confucianist had shared common Confucian characteristics in spite of their different purposes. The world view of the Confucianism such as sacrifice for sages, cultivation, devoting for study, teaching disciples, and education for villagers was revealed through the Confucian architecture including dwelling houses during the 16-17th century. Buildings of Confucianist were focused on the space for men. Seoae and Kyumam built two different Jeongsa's inside and outside of the boundary of the nakdong river. While Seodang and Jeongsa located outside of the boundary of the river were built excluding spaces for living, the function of the Jeongsa located inside of the boundary of the river was assimilated by Sarangcahe. However, both buildings kept the function for cultivation, devoting for study and teaching.

• Journal of the Korean Geographical Society
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• v.49 no.3
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• pp.423-437
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• 2014

Districting is a spatial decision making process to make a new regional framework for affecting human activities. Natural barriers such as rivers and mountains located within a reorganized district may reduce the efficiency of reorganized human activities. This implies that it is necessary to consider boundary characteristics in a districting process. The purpose of this research is to develop a new spatial optimization model based on boundary characteristics for districting problems. The boundary characteristics are evaluated as continuous value expressing the possibility of combining adjacent two basic spatial units rather than a dichotomous value with 1 or 0 and are defined as an objective function in the model. In addition, the model has explicitly formulated contiguity constraints as well as constraints enforcing demand balance among districts such as population and area. The boundary attributes are categorized into physical and relational characteristics. Suitability analysis is used to combine various variables related to each boundary characteristic and to evaluate the coupling possibility between two neighboring basic units. The model is applied to an administrative redistricting problem. The analytical results demonstrate that various boundary characteristics could be modeled in terms of mixed integer programming (MIP).

• Ocean Science Journal
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• v.43 no.4
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• pp.165-173
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• 2008

In this article, we describe a simple yet effective method for insertion of observational datasets in a mesoscale atmospheric model used in one-dimensional configuration through Nudging. To demonstrate the effectiveness of this technique, vertical profiles of meteorological parameters obtained from GLASS Sonde launches from a tiny island of Kaashidhoo in the Republic of Maldives are injected in a mesoscale atmospheric model - Advanced Regional Prediction System (ARPS), and model simulated parameters are compared with the available observational datasets. Analysis of one-time nudging in the model simulations over Kaashidhoo show that incorporation of this technique reasonably improves the model simulations within a time domain of +6 to +12 Hrs, while its impact on +18 Hrs simulations and beyond becomes literally null.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.595-600
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• 2011

This study analyzed passenger's access modes that connect to regional railway station and developed a model of access mode choice based on transit smart card data of Seoul station as a case study. The study boundary includes sixteen bus stops around the station. The results show that most passengers access to station have less than two transfers. Of total 15000, eighty percent of passengers use metro and the rest of people take a bus. Interestingly, it is found that almost same proportions of passengers use metro and bus for egress the station. Consequently, metro is found to be most likely used mode compared to bus for both access and egress trips.