• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.4
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• pp.150-155
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• 2020

Alumina (Al₂O₃) is mainly used as a structural ceramic material and to have good mechanical properties requires a dense microstructure. In commercial fabrication, the liquid phase sintering process is adjusted to reduce the sintering temperature of alumina. In this study, the effect of added amounts of cobalt oxide as a coloring agent on the microstructure and mechanical properties was investigated in the CaO-SiO₂-MgO-system liquid phase sintering of 92 % alumina at various sintering temperatures. When 11 wt% Co₂O₃ was added, a rearrangement of alumina particles, which is the main densification step in liquid phase sintering, occurred from a sintering temperature of 1200℃. Solution re-precipitation and coalescence steps followed from 1300℃ with the grain growth of alumina particles. The addition of excess Co₂O₃ and sintering temperatures above 1400℃ resulted in a decrease in sintered density and Vickers hardness, because of the low viscosity of the liquid phase. In 92 % alumina with the addition of 11 wt% Co₂O₃, a sintered density and Vickers hardness of 3.86 g/㎤ and 12.32 GPa, respectively, were obtained at a sintering temperature of 1350℃.

• Journal of the Economic Geographical Society of Korea
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• v.14 no.3
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• pp.241-262
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• 2011

The aim of this study is to examine the changes of institution, quantity and approach methods of research results in the history of Korean economic geography during the last fifty-five years (1956-2010) and to offer the preparations for the future research. The history Korean economic geography can be divided into four periods: 'period of cradle' (1956-1962), 'period of establishment' (1963-later 1970s)', 'period of leap (the former half of 1980s-the former half of 1990s)', and 'period of transition (since later 1990s)'. Many departments of geography education and geography have been founded in the 'period of establishment' and 'period of leap'. Among the total research matters (1,621), 44.4 percent of research results have been made in 2000s and the most researched field was that of manufacturing geography, which occupied 27.7 percent. In the approach methods, about two-thirds of the results are the empirical inductive approach and the research frameworks method which clarified the regional structures and theory of spatial system occupied each about 40 percent. In the future, each research field of Korean economic geography is expected to take more serious view of nature environment, thorough regional survey, and preference of economy-society-culture-knowledge in the research framework of spatial network theory.

• Culinary science and hospitality research
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• v.15 no.2
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• pp.255-267
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• 2009

The purpose of this study is to evaluate the importance and performance of the educational laboratory facilities for culinary practice. The questionnaire was distributed to 100 students enrolled in the culinary arts department at Y University located in Chung-buk province, and a total of 71 usable, completed questionnaires were received for the research. Collected data was statistically analyzed using the SPSS 10.0 Windows version, and the IPA(Importance-Performance Analysis) was conducted to compare importance and satisfaction from kitchen laboratory facilities which have been a key element of culinary education. Results of this study can be summarized as follows. Firstly, it was found that performance (M=3.42) for culinary practice facilities was lower than importance(M=4.09) for culinary practice facilities. Secondly, through IPA, the importance and satisfaction of culinary laboratory elements showed some differences between the students who had have some educational experience in culinary art prior to enrollmnet and those who had not. The former students attached importance to the usefulness of facilities rather than the size of facilities. And as rapidly improved factors, they answered ventilation and water supply facilities for culinary laboratories. The application of this study in physical environment of culinary education will contribute to improve students` satisfaction with the quality of education. However, the critical point of this study is a limited sampling, so the results of this study cannot be generalized.

• Journal of Korean Society of Forest Science
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• v.106 no.4
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• pp.371-379
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• 2017

This study was aimed to investigate the contribution of tree plantation, tree breeding and soil erosion control techniques developed during Saemaul Undong periods to the successful forest rehabilitation in the Republic of Korea. We surveyed a various literature of forest journals and had deep interview with forest experts who were actively involved in the forest rehabilitation projects. In the Republic of Korea, the forest rehabilitation was started with Saemaul Undong in 1970s and carried out to make the country green and to restore degraded forest lands by supports of tree plantation, tree breeding and soil erosion control techniques. Various techniques such as seed storage, seedling production, mass vegetative propagation (grafting and cutting) and special planting at denuded land or slash and burn site were developed for tree plantation. All techniques developed for the forest rehabilitation were connected with Saemaul Undong which caused active participation of local community people. Therefore, the development of tree plantation, tree breeding and soil erosion control skills had great impact on the job creation and income sources of local dwellers. It would be an applicable case to developing countries suffering with deforestation and forest degradation if the Korean skills developed for forest rehabilitation could be transferred.

• Korean Security Journal
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• no.35
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• pp.63-86
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• 2013

Security officers' intent to leave their job would have devastating effects on national security related industries. That is because excessive turnover would result in wasting the money for recruiting and training for organizations as well as putting the level of national security at risk. Therefore, this study has a goal to investigate the factors influencing the intent of leave job among security staff working for one of public institution, airports(n=198). Specifically, this study has a focus on examining the effect of job satisfaction, job commitment and security staff's level of commitment on national security on their turnover intent. The results of the multivariate ordinary lest square regression analysis reveal that job satisfaction, job commitment, and the level of national security commitment directly influence turnover intent. Also, the job satisfaction and the level of national security commitment has indirect impact on the turnover intent via job commitment. However, the results indicate that gender, age, and educational level are not related with security staff's decision to leave their job. Policy implications and study contribution were discussed in this study.

• Korean Security Journal
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• no.35
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• pp.7-36
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• 2013

Collecting international terrorism database is a challenging task not only for criminal justice personnel but also for criminologists in comparison to the case of common types of crime database. Yet, there has been growing interests and efforts in establishing a comprehensive terrorist events data base in the world. This current study has a goal to introduce an example world terrorism database case developed by START center in the United States. The START center developed the Global Terrorism Database (GTD) on the basis of by the Pinkerton Global Intelligence Service data (PGIS) originally collected by the Pinkerton. Furthermore, The START expended the GTD by collecting data from open source terrorist event data via internet and other resources. In this study, specifically, it describes the development and the nature of the GTD in general and the data collection efforts made by the STATA until today. Finally, this study provides a sketchy of the nature of the GTD data by showing the descriptive statistical analyses and time-series analyses result illustrating distribution of the world terrorism events. The limitation, policy implications and contribution of this study discussed in this paper.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.755-763
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• 2010

Fine sediment loadings from agricultural watersheds have led to habitat degradation in Lake Takkobu, northern Japan. Fifteen lake sediment core samples were obtained and analyzed to develop a chronology using physical sediment characters, $^{137}Cs$, and tephra. The reconstructed sedimentation rates over the past ca 300 years suggested that sedimentation rates increased drastically after land use development. With a natural sedimentation rate of 0.1-1.1 mm $year^{-1}$ until 1898, lake sedimentation accelerated to 0.6-12.8 mm $year^{-1}$ after 1898. The sedimentation rates after land use change, such as forestry, river engineering works, and agricultural development, were about 6-12 times higher than that under natural conditions, leading to accelerated lake shallowing over the last ca 100 years. Sedimentation rates between 1898 and 1963 differed with location in the lake because of spatial variation in the sediment flux from the contributing rivers and their watersheds. The sedimentation rate in the southern zone between 1898 and 1963 was significantly higher than that in the middle and northern zones, reflecting active sediment production associated with forestry for charcoal production and canal construction for transportation in the southern watersheds and wetlands. The sedimentation rate after 1963 did not vary among the three zones, because decreasing sedimentation was found in most of the southern sites whereas an increasing trend was observed in the middle and northern sites. This result can be explained by shallowing of lake-bottom morphology with sedimentation and the resultant reduction of sediment retention capacity in the southern zone. Moreover, the sedimentation rate at sampling sites close to river mouths increased by 5-32 times compared with natural rates before 1898. The Kushiro River, into which Lake Takkobu drains under regular flow conditions, further contributed to an increased sedimentation rate, because water from the Kushiro River flows back into Lake Takkobu during floods.

• Radiation Oncology Journal
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• v.10 no.2
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• pp.187-192
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• 1992

Local control is the important prognostic factor in cancer treatment because local control decrease the relative risk of metastatic spread and inclose distant metastasis free suwival. IORT is the modality which could increase local control without incressing complication, combined with curative operation. Eventhough we could achieve significant deacreased local failure by IORT and curative resection, it should not be committed as a main treatment modality without proving acceptable complications. Therapeutic Radiology Department of Yeungnam University Medical Center have tried 58 IORT from June 15, 1988, and performed 53 IORT En patients with gastric cancer. No local failure has been reported by regular follow up so far. Nine cases ($17\%$) of treatment related complicaiton were reported including intestinal obstrution, hemorrhage, sepsis, and bone marrow depression. These complications could be comparable to Jo's $25.2\%$ (chemotherapy + operation), Kim's $18\%$ (chemotherapy only in inoperable patients), because our treatment regimen is consisted of IORT (1500 cGy), external irradiation (--4500 cGy) and extensive chemotherapy(FAM, 5FU + MMC, BACOP).

• Land and Housing Review
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• v.5 no.1
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• pp.25-34
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• 2014

This study starts from the fact that we need residential complex for the purpose of public interests, rather than for profits, and find a new perspective on the concept of public-oriented residential complex in the cities that had slow growth. In this study, we 1) propose a new concept of the residential complex that can vitalize regional communities and maintain the interest of the public : 'functional-mix', 'social-mix', 'spatial-mix', 2) produce a model simulation based on the development principles including development direction, types of development, and design guidelines, ; six development principles(goal, concept, development type, spatial structure, space element, spatial hierarchy), diversity of housing types, facilities that can vitalize and contribute the regional communities 3) propose practical methods that can realize and promote the proposed concept and model simulation. ; need to amend the housing construction Law.

• Archives of design research
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• v.16 no.4
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• pp.163-172
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• 2003

Nowadays calligraphy technique is widely utilized in diverse areas throughout the world. It is adopted in the visual environment of modern people comprehending from graphic design areas such as advertisement, package, symbol marks, logotypes, and movie posters to modern abstract paintings. It is because its dynamic and suggestive power of expression as symbolic and kinetic representation has been appreciated anew. In response to modern people's aversion from the mechanical and artificial digital environment as well as from the uniform, official, and modernistic trend, calligraphy technique is attracting people's attention as a new expressive style with oriental mysticism and emotional intimacy. Therefore, this study aims at illuminating the history of calligraphy, understanding its characteristics, searching for the expanded value of modern paintings and graphic designs, and ultimately contributing to the propagation of visual languages and expressive styles. In addition, this study attempted to establish the concept of Calli-Illust, which combines oriental painting techniques and materials and calligraphy techniques, and to explore for its potential uses in order to expand the area of illustration. According to the results of this study, calligraphy technique is a painting style of abstract expressionism, contributing to the expansion of the territory of a new formative area. Furthermore, this study proved that it is necessary to develop new expressive styles to overcome the limitation of design styles based on western rational, logical, and geometric functionalism, which have been received uncritically in the design environment of diversity. What is more, the concept and definition of calli-illust, which has been understood as a part of the concept of calligraphy so far, were clarified Research on calli-illust is just in its beginning stage. The present researcher expects that deeper and more extensive studies will be carried out in the future, so that calli-illust can be applied to communication design in various ways.