• Journal of the HCI Society of Korea
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• v.5 no.1
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• pp.37-43
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• 2010

Twitter has been continuously growing since October, 2006. Especially, not only the users and the number of messages have been increasing but also a new concept in social networking called 'micro blogging' has diffused. Within Korea, service such as 'me2day' has already been introduced and the improvement of internet accessibility within mobile devices is expected to expand the 'micro blogs'. In this point, this research is executed to study the new medium, 'micro blog'. To do so, we collected and analyzed Twitter logs of Korean users. Especially, we were curious about the extreme heavy users using Twitter, despite of the linguistic and cultural barrier of the foreign service. Who they are, why and how they use the 'micro blog'. First, we reviewed the general aspect of followers and messages by collecting a certain number of random samples. Using the Lorenz curve we found out that there was the imbalance within the users and based on this phenomenon we deducted an extreme heavy user group. In order to perform further analysis, log analysis was performed on the extreme heavy users. As the result, the users used multiple mobile and desktop 'Twitter' clients. The usage pattern was similar to that of internet usage time but was used during their "micro" time. The users using 'Twitter' not only to spread messages about important information, special events and emotions, but also as a habitual 'chatting tool' to express ordinary personal chats similar to SMS and IM services. In this research, it is proved that 68% of the total messages were ordinary personal chats. Also, with 24% of the total messages were retweets, we were able to find out that virtually connected 'people' and 'relationships' acted as the dominant trigger of their articulation.

• Journal of the Korean association of regional geographers
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• v.8 no.3
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• pp.295-313
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• 2002

While the growth of Taegu has occurred through the land readjustment project, the public sector development project and the construction of roads, its growth pattern has been shaped by physical constraints such as mountains, streams and rail roads. The processes of urban growth of Taegu are classified into four stages: the stage of urban embryo in the Chosun Era; the formation stage of the basic urban system after the Japanese Colonial Era up to 1960; the stage of urban growth in the industrialization period from 1960s to 1980; and lastly, the stage of urban expansion and maturation, with construction of extensive newly developed districts, after the 1980s. Since its promotion to a metropolitan city with the inclusion of Seongseo, Wolbae, Gosan, Ansim and Chilgok in 1981, those regions have grown into newly developed residential districts, with its accompanying high density and high rise apartments complexes, through the public sector development project. These newly developed districts are located about six to seven kilometers away from CBD of the city along with main radial roads. The sites are also located on the route of the fourth belt way of the city. While the Sangin, Seongseo and Jisan Beommul newly developed districts have developed contiguously with the existing built-up areas, the Siji and Chilgok districts have developed separately by the green belt and the Geumho River, respectively.

• Communications for Statistical Applications and Methods
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• v.16 no.1
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• pp.41-50
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• 2009

Chain-linking is a method for aggregating volume measures which would improve the quality of estimates of economic growth over the present fixed base in Korea. There is a risk that choice of chain-linking techniques such annual overlap, one-quarter overlap or over-the-year overlap may create an artificial seasonality to the volume series. The empirical results on Korean GDP suggest that the use of the annual overlap is recommended. And conducting seasonal adjustment after chain-linking to produce the chain-linked seasonally adjusted GDP is more appropriated in Korea.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.160-161
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• 2017

Sentiment analysis and opinion mining is the field of study that analyzes people's opinions, sentiments, evaluations, attitudes, and emotions from written language Opinion mining and sentiment analysis(OMSA) as a research discipline has emerged during last 15 years and provides a methodology to computationally process the unstructured data mainly to extract opinions and identify their sentiments. The relatively new but fast growing research discipline has changed a lot during these years. This paper presents a scientometric analysis of research work done on OMSA during 2007-2016. For the literature analysis, research publications indexed in Web of Science (WoS) database are used as input data. The publication data is analyzed computationally to identify year-wise publication pattern, rate of growth of publications, research areas. More detailed manual analysis of the data is also performed to identify popular approaches (machine learning and lexcon-based) used in these publications, levels (documents, sentences or aspect-level) of sentiment analysis work done and major application areass of OMSA.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.1
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• pp.25-32
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• 2022

Investment casting is a production method commonly used to manufacture precision equipment, medical fields, and accessories, and has continued to develop through the modernization of equipment and high quality of materials, and its scope of use has been expanded. The purpose of this study is to minimize the defect rate by deriving structural improvement and standardization of mold temperature, which are key elements of the investment casting process, to minimize the defect rate. The scope of the study is limited to jewelry manufacturing casting processes suitable for understanding the structure and principles of small gate, and an experimental research is to be conducted by using soft Wax, gypsum powder, and 14 K gold as research materials. According to the results, the most appropriate casting standard temperature for the casting pattern of Alloy 14 k was the lowest turbulence at 980℃ flask temperature of 550℃, so good products could be produced. As a future task of this study, detailed studies are needed to data the structure and system temperature of small gate, reduce production defects in the field, and provide data for excellent investment casting competitiveness.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.262-262
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• 2016

최근 고해상도 디스플레이가 주목받으면서 기존 비정질 실리콘(a-Si)을 대체할 수 있는 재료에 관한 연구가 활발히 진행되고 있다. a-Si의 경우 간단한 공정 과정, 적은 생산비용, 대면적화가 가능하다는 장점이 있지만 전자 이동도가 매우 낮은 단점이 있다. 반면, 산화물 반도체는 비정질 상태에서 전자 이동도가 높으며 큰 밴드갭을 가지고 있어 투명한 특성을 나타낼 뿐만 아니라, 저온공정이 가능하여 기판의 제한이 없는 장점을 가지고 있다. 대표적으로 가장 널리 연구되고 있는 산화물 반도체는 a-IGZO(amorphous indium-gallium-zinc oxide)이다. 그러나 InZnO(IZO) 기반의 산화물 반도체에서 carrier suppressor 역할을 하는 Ga(gallium)은 수요에 대한 공급이 원활하지 못하여 비싸다는 단점이 있다. 그러므로 경제적이면서 a-IGZO와 유사한 전기적 특성을 나타낼 수 있는 suppressor 물질이 필요하다. 따라서 본 연구에서는 IZO 기반의 산화물 반도체에서 Ga을 Hf(hafnium), Zr(zirconium), Si(silicon)으로 대체하여 용액증착(solution-deposition) 공정으로 각각의 채널층을 형성한 back-gate type의 박막 트랜지스터(thin-film transistor, TFT) 소자를 제작하였다. 용액증착 공정은 물질의 비율을 자유롭게 조절할 수 있고, 대기압의 조건에서도 공정이 가능하기 때문에 짧은 공정시간과 저비용의 장점이 있다. 제작된 소자는 p-type Si 위에 게이트 절연막으로 100 nm의 열산화막이 성장된 기판을 사용하였다. 표준 RCA 클리닝 후에 각 solution 물질을 spin coating 방식으로 증착하였다. 이후, photolithography, develop, wet etching의 과정을 거쳐 채널층 패턴을 형성하였다. 또한, 산화물 반도체의 전기적 특성을 향상시키기 위해서 후속 열처리 과정(post deposition annealing, PDA)은 필수적이다. CTA 방식은 높은 열처리 온도와 긴 열처리 시간의 단점이 있다. 따라서, 본 연구에서는 $100^{\circ}C$ 이하의 낮은 온도와 짧은 열처리 시간의 장점을 가지는 MWI (microwave irradiation)를 후속 열처리로 진행하였다. 그 결과, 각 물질로 구현된 소자들은 기존 a-IGZO와 비교하여 적은 양의 carrier suppressor로도 우수한 전기적 특성 및 안정성을 얻을 수 있었다. 따라서, Si, Hf, Zr 기반의 산화물 반도체는 기존의 Ga을 대체하여 저비용으로 디스플레이를 구현할 수 있는 IZO 기반 재료로 기대된다.

• The Korean Journal of Financial Management
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• v.14 no.3
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• pp.23-56
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• 1997

본 연구는 주식의 시장가치와 거래빈도, 기관지분비율, 거래량 등에 따라 주식수익률의 시계열상관이 일정한 패턴을 갖는 것으로 나타나고 있다는 사실을 실증적으로 확인하고, 주식수익률의 시계열상관에 주된 영향을 미치는 요인을 횡단면 분석방법을 이용하여 살펴보고 있다. 1985년부터 1995년까지의 기간에 걸친 일별수익률자료를 이용하여 분석한 결과를 요약하면, 1) 규모, 거래빈도, 기관지분비율, 거래량 등이 작은 주식들로 구성된 포트폴리오일수록 수익률이 강한 양의 자기상관을 갖게 되며, 또한 그러한 변수들의 크기가 큰 주식들로 구성된 포트폴리오의 수익률에 대하여 후행하는 관계에 있다는 보여주고 있다. 2) Lo and MacKinlay(1990a)의 비거래모형을 이용한 분석결과에서는 한국주식수익률의 시계 및 상관이 전적으로 비거래로 인하여 나타나는 현상이 아니라는 것을 보여주고 있다. 3) 시계열상관의 정도를 나타내는 후행척도를 상기한 변수들에 대하여 회귀분석한 결과는 모든 변수들이 주식수익률의 시계열상관에 동시적으로 영향을 주고 있다는 것을 보여준다. 특히 시계열상관을 야기하는 요인들 중에서 거래빈도는 분석기간에 관계없이 항상 시계열상관에 음의 영향을 미치는 것으로 나타나고 있다. 기관지분비율과 거래량은 분명히 시계열상관에 음의 영향을 미치지만, 분석기간에 따라 유의성에 다소 차이를 보여주고 있다. 수익률의 변동성은 전반기의 경우에 시계열상관과 음의 관계를, 후반기의 경우에는 양의 관계를 갖는 것으로 나타나고 있다. 이러한 검증결과들로 미루어, 한국주식수익률의 시계열상관은 주가의 반응에 영향을 주게되는 시장구조나 투자패턴 등이 전 후반기에 있어서 서로 다르기 때문에 나타나는 현상으로 보인다.력(事前賣却努力)이 협의발행하에서 더 높았으나 발행일 직후의 주가회복은 보이지 않아 인수방식에 따른 가격안정화(價格安定化) 노력의 차이는 없었다. 발행기업들간의 주가차별화의 정도를 분석한 결과 협의발행에서 인회활동(認淮活動) (certification effects)을 더 잘 할 수 있다는 사실을 지지하지 못했다.범위(範圍)에 벗어나 한국주식시장(韓國株式市場)에서 주식시장(株式市場)의 비효율성(非效率性)을 배제할 수 없는 것으로 나타났다. 뿐만 아니라 차기에도 이어지고 화폐량과 소득이 주가의 결정에 영향을 미치고 있으며 다른 금융변수(金融變數)들은 영향을 미치지 않고 있다. 그러나 실질화폐잔고와 실질주가 장단기수익비율 화폐차등수익률과 소득변화률과는 장기적(長期的) 정상적(定常的) 균형관계(均衡關係)를 형성하고 있다. 따라서 장기적 관점에서 증권시장은 경제성장을 위한 통화정책과 각 분야의 균형적 성장을 유발할 수 있는 재정정책(財政政策)이 요청되고 있다. 위의 논의에서 유추할 수 있는 것은 화폐의 영향을 완화시키기 위하여 option시장의 개발과 농산물, 광물, 기타 실물 및 금융에 대한 선물시장의 개설이 요청된다. 이와 같은 시장을 통하여 통화 정책이 증권시장에 미치는 과도한 효과를 축소시켜 합리적이고 건전한 증권시장(證券市場)의 발전(發展)과 금융시장(金融市場)의 원활한 발전이 이룩될 수 있을 것이다. 자본시장이론(資本市場理論)에서는 화폐는 무시하고 실물적인 관점에서 증권가격의 결정을 연구하거나 위험분석에 주안점이 주어져 왔었다. 본 연구를 통하여 통화정책의 결과가 자본시장에 직접적으로 영향을 미치고 있음을 확인하였다. 통화금융정책과 주가의 유기적 관계를 확인한 본 논문의 결과를 정책당국이 참고하여

• Cartoon and Animation Studies
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• s.29
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• pp.173-207
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• 2012

The four-phased plot which consists of introduction, development, turn and conclusion in the long-story structure tends to be patterned and schematized. The behavior of characters is in line with the beginning of human beings and the plot of comic strips basically has four phases. It is, however, not a simple arrangement but a complex one which was developed by organizing patterns of human power, behavior and emotions. With the results from a survey with college students studying comic strips, this study aims to categorize four characters from the archetypal system by Carol Pearson, four phases of the hero's journey by Joseph Campbell, and the four phases of the plot based on Aristotle's theory, which is the frame of the comic strip structure through supporting evidence extracted from comic strips in an integrated way. In this study, the categorization is performed by simplifying and systemizing a character's life cycle, which is a factor of a story structure in complex comic strips. This study is to identify what comic strip writers express by using the metaphor in the complicated long-story structure of comic strips This study reveals that the structure of introduction, development, turn and conclusion based on the plot theory by Aristotle is the metaphor of human life and fate and that the phases of development in the archetypal system by Carol Pearson, a Jung researcher influenced by Jung's theory are the metaphor of human life and fate. Also, the theories of Joseph Campbell, who also was influenced by Jung, are the metaphor of human life and fate as they projected complex emotions of joy, anger, sorrow, and pleasure onto the archetype of heroes and used the metaphor of the hero's journey. Lastly, the theories are introduced with the approach of 'guide to screenwriters' by Christopher Vogler. Meanwhile, this metaphor is the objective and goal of this study. The comic strips selected for this study seem to have long complex stories which have characters leaving their homes, going through adventures and difficulties, meeting the world in another way, experiencing tension, competition, wars, and hardship and returning home with compensation. They grow mentally and psychologically through their journeys and finally become heroes. They express the meaning of our introspection in a narrative through plots and images of comic strips. This appears complex but the basic structure of long comic strips has four phases of plot. The life style of an extraordinary character traveling for adventures and growing in long comic strips can be divided into four phases symbolizing childhood, adolescence, adulthood, and senescence and it is a psychological growth process. The archetypes of the character can be divided into four phases and the growth process can be explained. The hero's journey symbolized by the character can be also divided into four phases. Through theories, the complex arrangement of four-phased plots in comic strips corresponds with the growth process of introduction, development, turn and conclusion through the stages of life. At the same time, this study found that the characters becoming heroes are the metaphor of introspection and that the characters' growth and life correspond with the four phases in life through long comic strips. Long stories in long comic strips written by comic strip writers show that characters go on their journeys and change their lives through hardship and difficulty by logical construction of plot and their growth processes are presented in archetypal images and they reach introspection as heroes. The readers share time and space through images in comic strips and realize that they had the same experience as the characters emotionally by being moved by the stories.

• Journal of the Korean Geographical Society
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• v.43 no.5
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• pp.743-760
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• 2008

This paper attempts to examine how Maryland's Priority Funding Area (PFA) designation and incentive program has influenced the location of infrastructure investment. Is Maryland's PFA program reducing sprawl? In order to answer this question, data on the water and sewer infrastructure investments between 1997 and 2003 are collected from each county in the state. Empirical works are composed of two parts. The first part of the empirical analysis examines the pattern of water and sewer investment that has gone in and outside the PFAs between 1997 and 2003 at the county level. The second part of the empirical study shows at a county level the conditions that influence decisions to go in and outside the PFA. Regression models with various specifications are used for the analysis. The findings reveal that state fund has worked as designed. The coefficients of state fund in all estimations are significant and have expected signs implying that a county with more state fund tends to invest more in PFA as less outside.

• Journal of the Economic Geographical Society of Korea
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• v.7 no.2
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• pp.261-281
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• 2004

The location of auto industry in Jeon-buk is due to the strategies for secure a low-priced industrial site of the auto assembly companies, which attained to quantitative growth stage in the early part 1990's, and the regional balanced development policy by the location of leader enterprise of the government. As a consequence of the reversal development pattern that is located the auto parts firm after locating the auto assembly companies, the Jeon-buk auto industry has many structural vulnerability. First, because of the lack development of auto parts industries, the auto assembly companies located in Jeon-buk are dependent many auto parts at a external region. Second, most of auto parts firm belongs to the singular assembly company exclusively. And the majority of auto parts industries are the low value-added products that are necessary a simple labor power. Third, the agglomeration undeveloped of associated industries with automobile caused a low competitiveness of invitation a manufacturing company as against other provinces. For a regional economic development by the auto industry, it is necessary a flexible regional structure of production through an agglomeration of associated industries. The geographical proximity between an assembly company and a parts firms is an important locational factor with the induction of Just-in-Time production system and a modularization in the auto industry. And a modularization applies to more new factory than the existing factories. So that, Jeon-buk self-government has to create an amicable industrial environment, try to attract an auto parts enterprises and plan an agglomerated industrial complex that is able to supply a parts modulated to assembly company.