• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.559-562
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• 2017

In city, tracing of power transmission lines is difficult due to compound installation of overhead and underground lines, transposition, bad view caused by trees or big buildings. It is hard problem for electrical technician on site to trace power transformers or power lines to serve customers in 3 phase -4 wires power distribution systems. It is necessary that the correct and fast tracing method is required for load balancing among distribution lines. Old technology use to trace off-lines with high power impulse injection. Our proposed method use to trace live lines with very small power high frequency signal injection. Typical power transformers in the distribution system prevent propagating the higher frequency carrier signal. The proposed method uses the limited propagation ability to identify the power transformer to serve customers. Two end communication terminals are required to be synchronized between them for determination on electrically same phases. Challenging issue is to achieve synchronization without GPS providing synchronizing time. A novel power transformer and wire identification system is designed and implemented. The system consists of a transmitter and a receiver with power-line communication module. Some experiments are conducted to verify the theoretical concepts in a big commercial building. Also some simulations are done to help and understand the concepts by using MATLAB Simulink simulator.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.505-508
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• 2016

In city, tracing of power transmission lines is difficult due to compound installation of overhead and underground lines, transposition, bad view caused by trees or big buildings. It is hard problem for electrical technician on site to trace power transformers or power lines to serve customers in 3 phase -4 wires power distribution systems. It is necessary that the correct and fast tracing method is required for load balancing among distribution lines. Old technology use to trace lines with high power impulse injection. Our proposed method uses to trace lines with very small power high frequency signal injection. Simulation models for 3-phase power transformers, 3-phase wire lines, and customer loads are described to investigate the transmission characteristics of high frequency power line carrier. Distribution lines have only a limited ability to carry higher frequencies. Typically power transformers in the distribution system prevent propagating the higher frequency carrier signal. The proposed method uses the limited propagation ability to identify the power transformer to serve customers. The system consists of a transmitter and a receiver with power-line communication module. Some experiments are conducted to verify the theoretical concepts in a big commercial building. Also some simulations are done to help and understand the concepts by using MATLAB Simulink simulator.

• Fire Science and Engineering
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• v.28 no.5
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• pp.89-97
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• 2014

At a time of growing importance of safety management in the social welfare facility by the increase of social welfare facilities, this study analysed safety perceptions about facility management, facility conditions, and facility structure and arrangement. This study sample consisted of 204 service providers and service users in 12 social welfare facilities. T-test and ANOVA were used to find the group differences among facility types. The findings were as follows. Firstly, safety perceptions of the service providers were significantly higher than those of service users in terms of facility management, and facility structure and arrangement. Secondly, in terms of facility types, the respondents in the family service center had lower safety perceptions than the respondents in other service in all three areas. Thirdly, facilities that are of 10 years or older had higher safety perceptions than the respondents of facilities that are 6 to 10 years old in the area of facility management, and facility structure and arrangement. Fourthly, in regard to building heights, the respondents in 3 to 4 story facilities had statistically higher safety perceptions than respondents in 1 story facilities. Finally, looking at the relationship between floor area and safety perceptions, safety perceptions of the respondents of less than $400m^2$ facilities or $600m^2$ and more facilities were significantly higher than those of $400m^2{\sim}$ less than $600m^2$ facilities.

• Korean Journal of Health Education and Promotion
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• v.26 no.5
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• pp.71-84
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• 2009

Objectives: This research intended to examine the relationships among social capital, socioeconomic factors, and health-related lifestyles and the effect of these factors on self-rated health in the Republic of Korea. Methods: The data of the social statistics survey that the Korea National Statistical Office conducted in 2006 were chosen and 37,928 people from them, who were 25~59 years old were sampled. This paper made path analysis to examine the relationships among social capital, socioeconomic factors, and health-related lifestyle and the influence of these factors on self-rated health. Results: In relation to the overall influences of socioeconomic factors, social capital, and health-related lifestyle on self-rated health, the following factors had a significant positive direct effect: education(0.069), subjective class(0.108), marriage(0.054), satisfaction with family relationships(0.087), reliability of institutions(0.020), citizens' participation(0.021), exercise(0.037), and refrain from smoking(0.011). However, abstinence from alcohol(-0.067) had a negative direct effect on self-rated health Conclusion: Based on the results, this paper can suggest that the plan of keeping and building up social capital should be considered in the whole aspects of the society and the project promoting drinking moderation is required to consider social culture than individuals.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.4
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• pp.10-16
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• 2013

Korean housing developers are in a very competitive market and their way of attracting buyers is landscaping better than competing firms do. Thus, transplanting larger pine trees(Pinus densiflora S. et. Z.) is in vogue. A typical case is a pine tree about 30-year old, 35 diameters at breast height, transplanted 223 km afar from the Gangwon Province to Seoul. We estimated and compared carbon emissions during the whole transplanting works, and carbon intake by the tree if it survives 50 more years on site. Findings are; first, a large tree will take up and sequestrate approximately 90 kgC if it survives 50 more years. Second, transplanting works emit approximately 113.69 kgC, which is about 1.26 times of its possible future intake of carbon. Landscaping is a legal requirement for the purposes not only of aesthetics but also of environmental quality. Transplanting larger trees that came from a dam or a road building site may be inevitable and acceptable. However, transplanting larger trees long distance was evaluated to be harmful to the environment. It is strongly recommended to prohibit transplanting large trees. Landscape professionals need to guide clients to have desirable consumer attitude.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1968-1975
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• 2011

This study was performed to propose a development guide for the periphery of local industrial park in the region of Hongseng-gun located at the mid-west of Chungnam province., which is a representative agrarian society, has been approached to a super-aged society where the region shows a continuous decrease in population, and the composition ratio of old ages is about 17.1%. Also, the region is a period of a low ebb due to the traditional agriculture based industrial structure in producing mainly simple productions. Many local governments in agrarian and fishing regions have been efforted for luring some businesses in their regions by constructing industrial complex competitively in order to solve such structural problems in such local regions. However, in some cases, these efforts cause certain destructions in the local original natural environment due to such development of industrial complex and the decrease in the settlement environment of residents. The objective of this study is to establish a local development plan for building the sustainable and comfortable settlement environments based on the settlement of the residents and the labors in such industrial complex by preventing sprawl developments in the construction of general industrial complex. This study was processed as following procedures. First, this study drew the trend in the change of the local society of H-gun through collecting literatures and analyzing it. Second, this study proposed a proper level of settlement environments required to the development of surroundings in such industrial complex based on the survey of the consciousness of residents using a statistical method. Finally, this study proposed a development guide for the surroundings based on the proposed level of settlement environments.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.1
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• pp.159-169
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• 2012

Seokgasan(石假山) is originated in Goryeo, is a Korean traditional technique handed down to Joseon and Seokgasan is the Korean creative culture of gardening by artificial stones, which replicates small artificial mountain of natural landscape in the garden. The object of this study is Seokgasan made by Seong-im(成任), who was a civil minister in Joseon and lived from 1421 to 1484, in his residence located in Inwang Mountain, Hanyang and the purpose of this study is to investigate the historical meaning and symbol of Seokgasan made by Seong-im on the base of the relative old literatures and embody its shape and structure. According to the result of this study on Seokgasan of Seong-im, it can find out some facts as follows; Seokgasan of Seong-im in the early Joseon succeeded to the structural form of Seokgasan of the artificial rock mountain type connected pond, which was made-up firstly in the garden of the Palace of Manwoldae in the Middle Goryeo, and it was called firstly as 'Seokgasan' in the garden of Seong-im's house. Seong-im's Seokgasan in the early Joseon had more concentrated philosophical meanings, including the idea of taoist immortal, than those in the Goryeo dynasty and was be emblematic of an imaginative space. Also there were lots of gardens modeled on the famous mountains and famous lakes in China much the same as the Goryeo dynasty. In addition, there was an exceptional purpose for building Seokgasan which could not be found in the Goryeo dynasty. That was practicality for emotional stability and cure. Seong-im's Seokgasan is record-relics with high value of landscape architecture history, which can identify its historical meanings, shapes and structural frames succeeded from the Goryeo dynasty.

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.1
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• pp.25-47
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• 2015

The user behaviors in the parks around the commercial area may have different characteristics in comparison with the behaviors in typical neighborhood parks because they may be affected by nearby commercial facilities. The purpose of this study is to explore the characteristics of park users'behavior considering adjacent environments in the neighborhood parks located in central business district of Daegu and to suggest improvements and complements for the construction of new parks and remodeling current parks. According to the results, the land values were high and the percentage of deteriorated buildings was low around Gukchae Reward Movement Memorial Park and 2.28 Central Memorial Park. However, the commercial facilities were entirely declined along with a drop in land values around Gyeongsang-gamyeong Park and old people used this park more than young people. In terms of the purpose of park use, users of three parks had indirect behavior patterns related near commercial facilities rather than using directly park facilities and the age groups of park users were similar to the user groups of nearby commercial facilities. Also, the determinant factors of satisfaction with park use were varied depending on the difference of age groups of park users and park characteristics. Therefore, it is necessary to consider the effects of user age groups according to the changes of environment around parks for the construction and organization of parks.

• Journal of the Korean Wood Science and Technology
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• v.46 no.3
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• pp.278-284
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• 2018

This study is for species identification for each structure member such as Pillar, Bo, Changbang, Dori, Jangyeo, Judu, Donjaju, Chunyeo, Guitle, and Jongdae, of Pungnammun Gate (Treasure 308). Jeonju is the birthplace of Joseon Dynasty and Pungnammun Gate was the southern gate of old Jeonjueupseong which was walled town. Provincial Governor of Koryeo Dynasty, Yu Gyeong Choi built Jeonjubuseong and four gates at all cardinal points in 1388. And the gate was burnt down by Jeongyujaeran (war with Japan in 1597). It was rebuilt by King Yeongjo (Joseon Dynasty) in 1734 and renamed 'Pungnammun' after 34 years. It was designated for Treasure 308 for its unique style of architecture and historic values in 1963. In this study, all of wooden structure members were Pinus spp.. This result was matched for the result of major species for wooden building of late Joseon Dynasty. It can be used to complete database for architecture of Castle's Gate and help for restoration of cultural heritage in the future.

• Elastomers and Composites
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• v.38 no.3
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• pp.243-250
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• 2003

Polyurethane waterproof (PW) coatings are increasingly demanded in Korea for repairing cracks on old building roofs and construction of many sporting facilities. Calcium carbonate, a common filler, is incorporated in PW compositions. In this study, PW coatings were prepared by substituting a part of calcium carbonate with fly ash. The maximum amounts of calcium carbonate which can be substituted by fly ash obtained in the cyclone and bag filter dust collectors were 20 and 10%, respectively. It was found that the curing rate of PWs ran be controlled by varying the amount of Pb-octoate catalyst. The elongations at break as well as tensile strength and tear strength of PW coatings containing fly ash could also be adjusted such that their values were comparable to those of a standard PW coating by varying relative amounts of some components. However, the amount of cadmium, mercury, and lead leached from PW coatings containing fly ash obtained from the bag filter collector exceeded the respective allowed upper limits, mainly due to the initial high contents of them in the fly ash. On the other hand, PW coatings containing fly ash obtained from the cyclone collector exhibited better mechanical properties and did not release any significant amounts of the heavy metals. Thus, it was concluded that PW coatings containing fly ash can be utilized for practical applications as long as an appropriate fly ash is used.