• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.12
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• pp.1165-1171
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• 2011

In this paper, we investigate hidden node problem to effectively utilize TV band devices(TVBDs) in the TV white space(TVWS), and also to protect digital television(DTV) service in Korea. Firstly, we classify the radio propagation environment into an urban area, a basin area, and a coastal area based on geographical characteristics. Thereafter, we measure and analyze local shape based hidden node attenuation at eight segmented positions in each geographic area. Because commercial buildings as well as residential and commercial buildings in Korea are located in closer proximity to each other than in other countries, hidden node margin should be more than 38 dB in order to safely protect DTV service in Korea.

• Journal of Preventive Medicine and Public Health
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• v.12 no.1
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• pp.49-55
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• 1979

In order to investigate air pollution by heavy metals in Seoul city, the suspended particulates in the atmosphere were sampled with high volume air sampler in industrial area(Ku Ro Dong), commerical(Kwang Hwa Moon) and residential(Shin Chon Dong) from January to November, 1977. The sampled suspended particulates were digested and extracted from suspended particulates with the acidic solution by reflux-extraction technique, and were measured by atomic absorption spectrophotometry. And mercury was measured by mercury analyzer applying the reducing sublimation technique. Among heavy metals analyzed, the iron was identified at the highest level in the suspended particulates and the chromium was the least. Through the surveyed area, the concentration of heavy metals of the industrial area was comparatively high among others and the commercial was the second. It was detected that lead was the most concentrated in the suspended particulate of the commercial area, that might be caused of the traffic emissions. The seasonal variations were analyzed and the correlations among heavy metals and total suspended particulate were also calculated. Especially, the iron was highly correlated with total suspended particulate in all the surveyed areas.

• Ocean and Polar Research
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• v.36 no.4
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• pp.367-371
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• 2014

In early 1990s, the Korean government has launched a deep-sea research program to secure the stable long-term supply of strategic metallic minerals including Cr, Cu and Ni. Through the pioneering surveys, Korea registered $150,000km^2$ of Mn-nodule field in the Clarion-Clipperton area, the NE equatorial Pacific to the international sea-bed authority (ISA) in 1994. Following the ISA exploration code, the final exclusive exploration area of $75,000km^2$ was assigned in 2002, based on results of eight-year researches of chemico-physical properties of nodules, bottom profiles and sediment properties. Since that time, environmental studies, mining technical developments including robot miner and lifting system and establishment of smelting systems were accompanied with the detailed geophysical studies to decipher the priori mining area until 2009. Major points of the recent Korea Mn-nodule program are deployed on a commercial scale until 2015. In order to meet the goals, we developed a 1/5 scaled robot miner compared to commercial one in 2012 and performed a mining test at the water depth of 1,370 m in 2013. In addition, detailed 25,000 scaled mining maps in the priori area, which can provide operation roots of the miner, will be prepared and an environmental-friendly mining strategy will be pursued based on the environmental impact test and environmental monitoring.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.4
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• pp.171-183
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• 1998

The purpose of this study was to analyze urban greenspace area and vegetation structure by land use types for both Chuncheon and Kangleung. Natural and agricultural lands were predominant in the study cites, as 75-80% of total area. Residential lands accounted for about 10%, and commercial and industrial lands(including transportation), 5-10%. Only 10-20% of urban residential and commercial area was covered with greenspace. Woody plant cover was 12-13%, and tree density was 1.5 trees/100$m^2$ for urban lands(all land use types except natural land) in both cities. The tree-age structure was largely characterized by young, growing tree population, and species diversity within a diameter class decreases as the diameter classes get larger. Urban lands of both cities had quite a similar species composition of woody plants (similarity index of 0.65). Street trees in Chuncheon were intensively pruned annually to protect the above ground utility lines. Some strategies were explored to solve problems found in the existing greenspace structures. They included increase of biomass and greenspace area through minimization of unnecessary impervious surfaces, creation of multilayered and multiaged vegetation structures, relocation of above ground utility lines and avoidance of intensive tree pruning, and establishment of greenspace proximity and connectivity.

• Nuclear Engineering and Technology
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• v.54 no.1
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• pp.326-342
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• 2022

Comparative analyses of a shield building subjected to a large commercial aircraft impact between decoupling method and coupling method are performed in this paper. The decoupling method is applying impact force time-history curves on impact area of the shield building to study impact damage effects on structure. The coupling method is using a model including aircraft and shield building to perform simulation of the entire impact process. Impact force time-history curves of the fuselage, wing and engine and their total impact force time-history curve are obtained by the entire aircraft normally impacting the rigid wall. Taking aircraft structure and impact progress into account some loading areas are determined to perform some comparative analyses between decoupling method and coupling method, the calculation results including displacement, plastic strain of concrete and stress of steel plate in impact area are given. If the loading area is determined unreasonably, it will be difficult to assess impact damage of impact area even though the accurate impact force of each part of aircraft obtained already. The coupling method presented at last in this paper can more reasonably evaluate the dynamic response of the shield building than the decoupling methods used in the current nuclear engineering design.

• Journal of Engineering Education Research
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• v.19 no.1
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• pp.31-36
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• 2016

These days, ICT-related products are pouring out due to development of mobile technology and increase of smart phones. Among the ICT-related products, wearable devices are being spotlighted with the advent of hyper-connected society. In this paper, a body-attached type wearable device using EMG(electromyography) sensors is studied. The research field of EMG sensors is divided into two parts. One is medical area and another is control device area. This study corresponds to the latter that is a method of transmitting user's manipulation intention to robots, games or computers through the measurement of EMG. We used commercial device MYO developed by Thalmic Labs in Canada and matched up EMG of arm muscles with gesture controller. In the experiment part, first of all, various arm motions for controlling devices are defined. Finally, we drew several distinguishing kinds of motions through analysis of the EMG signals and substituted a joystick with the motions.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.5
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• pp.439-445
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• 2003

The purpose of this study is to suggest the improvement strategies for exhaust performance in composite kitchen hoods. The Exhaust only hood, the 2-way compensating hood and the 3-way compensating hood were selected, and the laboratory experiments were performed to compare the local exhaust efficiency and the indoor temperature distributions according to the variations of the hood type and supply/exhaust air velocity. The results of this study can be summarized as follows. The compensating hood has better performance than exhaust only hood in the aspect of local exhaust efficiency and temperature distribution. The 3-way compensating hood shows the best performance when the supply air velocity is about 2.7 m/s, and the 2-way compensating hood at the supply air velocity of 3.5 w/s. In the same exhaust rate condition, if the exhaust area of the hood is increased and therefore the exhaust velocity is lowered, the supply air velocity is also lowered to get the optimum performance. The optimum exhaust velocity range of the commercial kitchen hood which derived from this study is 0.48 ∼ 0.55 m/s.

• Journal of Arbitration Studies
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• v.31 no.2
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• pp.77-98
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• 2021

International commercial mediation of intellectual property rights fully meets the interests of the parties in such disputes in terms of their needs for neutral forum of dispute resolution, cost-effective settlement, objective opinion of relevant experts, internationally enforceable solution. In addition, as a procedural flexibility, respected self-determination of the parties, exploration of possible creative business solutions, maintenance of business relationship and confidentiality of mediation are major characteristics which can be competitively differentiated from the lawsuit or arbitration. The settlement agreement as a result of the WIPO mediation has an effect of contract while the settlement agreement as a result of most domestic ones has an effect of judicial reconciliation which can be domestically enforced. The latter is not subject to the application of the Singapore Convention on Mediation which establishes a harmonized legal framework for the right to invoke settlement agreements as well as for their enforcement. The WIPO international mediation system and its experience may be a good reference for Korea to take an initiative to establish a globally competitive international mediation system in the area of intellectual property rights.

• Journal of the Korean Solar Energy Society
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• v.39 no.3
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• pp.19-27
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• 2019

In commercial areas, outdoor units are typically installed close to one another in the narrow space between buildings due to insufficient regulations. This makes it difficult to ventilate the discharge airflow, which may lead to deterioration of the performance of outdoor units. This study conducted CFD simulation to analyze the thermal environment according to the installation distance of the outdoor unit. The outdoor unit was installed in the space between buildings, and the thermal environment was analyzed by changing installation distance and wind speed. The performance of the outdoor unit was evaluated by measuring the on-coil temperature. The results show that the closer the distance between outdoor units, the higher the condenser on-coil temperature. Also, the on-coil temperature appeared to rise dramatically at lower wind speed.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.10
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• pp.55-61
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• 2018

Changes in consumer purchasing patterns due to construction of large Western-style commercial buildings and introduction of new purchasing methods in South Korea in the 1990s led to a gradual decline in traditional markets. Under such a new environment, Yukgeori market, one of Korea's exemplary markets, has continued to develop and survive, while maintaining the traditional market form of Korea, both physically and operationally. Therefore, to find the characteristics of spatial configurations supporting the revitalization of traditional market, we deduced social attributes of spaces in street network of Cheongju city and the neighborhood including Yukgeori market by calculating the depths of nodes in the network using analysis models based on space syntax. The results illustrated that long street with the function to attract people and acts as a bridge of traffic and communication between highly modernized commercial area and traditional market can lead to continuous win-win development of both areas and the revitalization of traditional market through the promotion of social activities in the market. We expect that sound and sustainable development of contemporary cities, which lost tradition, will be achieved through the results of this study.