• Journal of the Korean earth science society
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• v.22 no.3
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• pp.237-247
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• 2001

The concentrations of gaseous mercury (Hg) determined between two different time periods of the late 1980s and the late 1990s were compared to account for the effects of changes between source/sink relationships of atmospheric Hg in an urban area. The Hg concentration levels were different remarkably between the two time periods due possibly to changes in source/sink relationships. The results showed that the Hg levels in the former period were measured to be 14.4${\pm}$9.56ngm$^{-3}$ (N = 2714), whereas those of the latter period were characterized by approximately three-fold decreased values of 5.34${\pm}$3.92 ngm$^{-3}$ (N=2576). Using two independent measurement data sets, we examined the patterns of Hg distribution at different time scales. When analyzed over 24 hour scale, these data sets exhibited two distinctive distribution patterns. The former period showed enhanced concentration levels during daytime, while the latter period showed relative depletion during daytime. The patterns of the two data sets were also examined over seasonal scale. The results of two different time periods consistently showed the occurrences of maximum seasonal values during winter. The former period was characterized by seasonal patterns of fuel consumption with excessive Hg levels during winter. Conversely, no distinctive trend was apparent for the latter period with slight changes in concentration levels across seasons. In order to analyze the factors affecting Hg distributions between two different periods, we conducted both correlation and factor analysis on both all data sets and on seasonally divided data groups. The results of these analyses consistently indicate that the Hg concentration levels for two different time periods are regulated by distinctive source processes that are characteristic of each period.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.581-585
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• 2002

Focal epithelial hyperplasia(FEH) is Human papilloma virus - induced, localized proliferation of oral squamous epithelium. FEH usually occurs in the childhood, but occasionally affects the young and middle-aged adults. Sites of the greatest involvement include the labial, buccal and lingual mucosa, but lesions of gingiva or tongue have also been reported. This disease is typically characterized by multiple soft, non-tender flattened papules and plaques. Occasional lesions show a slight papillary surface change. Individual lesions are small, discrete and well demarcated. The histopathologic hallmark of FEH is acanthosis of the oral epithelium. Cells demonstrating viral cytopathic changes including koilocytes or mitosoid cells may be present. The 5-year-old female of this case visited Department of Pediatric Dentistry, College of Dentistry, Yonsei University with a chief complaint of exophytic lesions on gingiva. Sessile papillary papules were detected by clinical examination on buccal gingiva at the maxillary left and right second deciduous molars. The patient did not complain of pain by palpation. An excisional biopsy was carried out for a histological examination and acanthosis was observed. The lesions were diagnosed as FEH. FEH would regress spontaneously after several months or years. Conservative excision may be performed for diagnostic or esthetic purpose. The risk of recurrence after this therapy is minimal, and there is no malignant transformation.

• Applied Chemistry for Engineering
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• v.27 no.6
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• pp.639-645
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• 2016

We herein report efficient triplet-triplet annihilation upconversion (TTA-UC) achieved in various non-toxic and non-volatile vegetable oils as a UC media using platinum-octaethylporphyrin (PtOEP) and 9,10-diphenylanthracene (DPA) as a sensitizer and acceptor, respectively. Green-to-blue UC was readily achieved from PtOEP/DPA solution in vegetable oils with the quantum yield of 8% without any deoxygenation process. The UC efficiency was found to be significantly dependent on the contents of unsaturated hydrocarbon in vegetable oils and viscosity of the solution, as well. Though the Stern-volmer constant and quantum yield in vegetable oils were measured to be lower than those measured in the deaerated organic solvent, the quenching efficiency was still high enough to be 93%. In the sunflower oil, the UC threshold intensity ($I_{th}$) was approx. $100mW/cm^2$, which is far larger than the sunlight intensity, but we believe that the UC achieved in non-toxic and air-saturated media was still highly applicable to nontraditional visualization techniques such as bioimaging.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2001.05a
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• pp.79-82
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• 2001

이동코드는 자바 애플릿(applet)이나 스크립트와 같이 원격지에서 실행가능한 코드로서 현재 웹브라우저를 통하여 쉽게 수행 가능하다. 이러한 프로그램은 누구나 작성할 수 있고 브라우저를 수행할 수 있는 어떤 컴퓨터에서도 수행 가능하다. 즉, 자바 애플릿과 같이 운영체제나 하드웨어에 관계없이 어떤 플랫폼에도 동일 코드가 수행될 수 있다. (일반적으로 에이전트도 이동 코드라고 부르지만 여기서는 포함시키지 않는다.) 인터넷에서 어떤 컴퓨터에서도 공통적인 스크립트를 수행할 수 있다는 것은 편리함, 가능성에서 많은 장점을 가지고 있지만 보안 관점에서 보면 이러한 공통의 스크립트를 수행할 수 있는 인터프리터는 매우 위험하다. 또한 이러한 인터프리터가 브라우저의 한 부분이기 때문에 위험은 더욱 증가한다. 이동 코드 인터프리터에서 어떤 버그가 존재할 경우 이것을 이용한 악성 사용자가 프로그램을 특정 컴퓨터에서 수행시켜 접근 권한을 쉽게 얻거나 시스템을 파괴할 수 있다. 일반 사용자들이 주로 사용하는 윈도95 같은 운영체제에서는 이러한 공격을 막을 보호대책이 없고 심지어 UNIX에서도 사용자의 권한을 가지고 이동 코드가 수행되기 때문에 사용자의 파일을 조작하거나 정보가 유출될 수 있다. 또한, 이동코드가 서로 다른 수행환경을 이동할 경우, 악성 이동코드로부터 영향을 받을 수 있는 수행환경의 보호와 악성 호스트 및 수행환경에 의해 이동코드가 파괴되는 경우도 있다. 위와 같은 이동 코드의 위험으로부터 발생할 수 있는 보안문제점들의 실제 피해 사례 및 시스템을 보호하기 위해 사용되어온 몇 가지 기법을 제시하였다.사업을 통하여 경남지역 산업단지에 입주한 기업체의 정보 활용을 극대화하여 지역경제 발전에 기여함과 동시에 국내 지역정보화 시범모델로서 위상을 확립하고자 한다.을 기업의 타인자본비용과 자기자본비용의 조합인 기회자본비용으로 할인함으로써 현재의 기업가치를 구할 수 있기 때문이다. 이처럼 기업이 영업활동이나 투자활동을 통해 현금을 창출하고 소비하는 경향은 해당 비즈니스 모델의 성격을 규정하는 자료도로 이용될 수 있다. 또한 최근 인터넷기업들의 부도가 발생하고 있는데, 기업의 부실원인이 어떤 것이든 사회전체의 생산력의 감소, 실업의 증가, 채권자 및 주주의 부의 감소, 심리적 불안으로 인한 경제활동의 위축, 기업 노하우의 소멸, 대외적 신용도의 하락 등과 같은 사회적·경제적 파급효과는 대단히 크다. 이상과 같은 기업부실의 효과를 고려할 때 부실기업을 미리 예측하는 일종의 조기경보장치를 갖는다는 것은 중요한 일이다. 현금흐름정보를 이용하여 기업의 부실을 예측하면 기업의 부실징후를 파악하는데 그치지 않고 부실의 원인을 파악하고 이에 대한 대응 전략을 수립하며 그 결과를 측정하는데 활용될 수도 있다. 따라서 본 연구에서는 기업의 부도예측 정보 중 현금흐름정보를 통하여 '인터넷기업의 미래 현금흐름측정, 부도예측신호효과, 부실원인파악, 비즈니스 모델의 성격규정 등을 할 수 있는가'를 검증하려고 한다. 협력체계 확립, ${\circled}3$ 전문인력 확보 및 인력구성 조정, 그리고 ${\circled}4$ 방문보건사업의 강화 등이다., 대사(代謝)와 관계(關係)있음을 시사(示唆)해 주

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.69-75
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• 2011

This study was conducted to investigate the variation of cone, seed and germination characteristics among populations and among individuals within populations of Picea jezoensis(Siebold & Zuccarini) Carriere distributed in Korea. Cone collected from 25 trees in two natural populations(Mt. Jiri and Mt. Dokyu) and their thirteen cone and seed characteristics as well as three germination behaviors were analyzed. Statistical analysis showed significant differences among populations and among individuals within populations in 9 traits except for seed breadth, seed weight, index of seed wing and mean germination time. Generally, morphological variation of cone and seed wings from Mt. Jiri population has smaller and longer than those of Mt. Dokyu population. Percentage of sound seeds and Tetrazolium test from Mt. Jiri population showed 1.79 and 1.87 higher values than Mt. Dokyu population, respectively. The maximum germination percentage was obtained at the optimum temperature of $20^{\circ}C$ and in this case, mean germination time and germination rate showed 7.5 days and 2.9 ea./day, respectively. In seed germination behaviors, percentage(40.7%) and rate(0.90 ea./day) of germination in Mt. Jiri population were more higher and faster than those of Mt. Dokyu population(17.7%, 0.37 ea./day). According to correlation analysis, P. jezoensis populations with small restricted distribution may have been reduced because seed qualities were correlated with increased levels of inbreeding and disproportion flowering.

• Journal of Korea Water Resources Association
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• v.41 no.3
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• pp.293-303
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• 2008

Reservoir turbidity flows degrade the efficiency and sustainability of water supply system in many countries located in monsoon climate region. A decision support system called RTMMS aimed to assist reservoir operations was developed for the real time monitoring, modeling, and management of turbidity flows induced by flood runoffs in Daecheong reservoir. RTMMS consists of a real time data acquisition module that collects and stores field monitoring data, a data assimilation module that assists pre-processing of model input data, a two dimensional numerical model for the simulation of reservoir hydrodynamics and turbidity, and a post-processor that aids the analysis of simulation results and alternative management scenarios. RTMMS was calibrated using field data obtained during the flood season of 2004, and applied to real-time simulations of flood events occurred on July of 2006 for assessing its predictive capability. The system showed fairly satisfactory performance in reproducing the density flow regimes and fate of turbidity plumes in the reservoir with efficient computation time that is a vital requirement for a real time application. The configurations of RTMMS suggested in this study can be adopted in many reservoirs that have similar turbidity issues for better management of water supply utilities and downstream aquatic ecosystem.

• Parasites, Hosts and Diseases
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• v.32 no.3
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• pp.195-200
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• 1994

Malaria is estimated to have a worldwide incidence of more than 100 million clinical cases and approximately 1 miuion deaths per year. Korea, although previously tnlown as an endemic area of tertian malaria (Pzosmonin vivax), has been considered free from malaria as there had been no report on indigenous cases since 1984. Recently, however, we experienced an indigenous case of P. viuax infection in a young man who had never been abroad. The patient was a 23-year-old Korean soldier with 18-day history of recurrent fever and chill lasting 4 to 8 hours on alternative days since mid-July 1993. He had lived in Changwon, Hyongsangnam-do, before entering barracks located in Paiu-gun, Kyonggj-do on Jne 1992, and had never been out of Korea. He had no history of blood transfusion nor parenteral use of drugs. The peripheral blood smears showed typical ring forms, trophozoites, and gametocytes of p. uiuox, in addition to mild anemia and thrombocytopenia. After confirmation of the diagnosis, he was treated with hydroxychloroquine and primaquine. Follow-up blood smears no more revealed malaria parasites. It is not certain whether the present case is due to a resurgence of indigenous malaria or a secondary infection from introduced mnuia. Whichever the source of infection the domestic occurrence of mnuia cycle in Korea should be a warning sign in public health point of view.

• International Area Studies Review
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• v.20 no.2
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• pp.113-140
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• 2016

This paper first extracts the main basis for the Middle-Income Trap(MIT) to apply these grounds to reality of the Chinese economy. And then confirmed crisis factors of China economy. Also discussed then the economic reforms of China in order to not fall into the MIT. After reviewing previous research extracted six factors the results will correspond to comply with the Chinese economy. Those are 'Over-investment', 'excess capacity' 'reduction of TFP continued,' 'disappearance and the aging of the population bonus', 'excessive debt and structural adjustment and financial instability of the company', 'income unequal expansion', 'low financial and information infrastructure accessibility', and 'low transparency index'. China's policy direction to avoid the MIT generally set properly, but proof that implementation process not easy, was appearing everywhere. After all, China economy should be modified now to a reforms of 'government failure' and promotion of function for ongoing restructuring system in the market. Because of the SDR incorporation from 2015, it is inevitable to face major constraints in the external aspects.

• Journal of Digital Convergence
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• v.17 no.6
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• pp.201-209
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• 2019

Recently various start-up competitions have been held in the government, public and private sectors. There is a need to improve the business model of the majority of preliminary founders and early founders through the start - up contest, while improving the possibility of commercialization. The purpose of this study is to analyze the present status of various start - up contests based on the actual survey results of the major start - up contest operators and major participants in Korea. The main results of this study are as follows: First, in the run - up contest, there is a tendency to break out of the event personality, to prevent the opening of the business model of the entrepreneur in the competition, to reduce the formal procedure considering the input time, Improvement of the use of presentation materials, and the purpose of the contest and precise specification of the object of the recruitment. Secondly, it is necessary to establish a juror and a mentor pool with expertise. It is necessary to establish the judges and the mentor pool with expertise in each field, allocate the region according to the regional composition, entrust the judges with entrepreneurial experience, and introduce the post evaluation system for the judges after the competition. Third, most of the contest winners are manufacturing / technology-based businesses.

• Korea and Global Affairs
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• v.3 no.1
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• pp.107-150
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• 2019

The article is intended to examine the four main vocalists, including Freddie Mercury, of the legendary rock group Queen, whose movie has generated a "Queen Syndrome" all over the world, and is widely shared by nearly 10 million viewers in Korea. In today's era of cultural content, this paper studied the relationship between their personality and character in the sense of storytelling for the four Queen members who left charismatic voices and beautiful pop music harmonies. As a theoretical background, I will focus our research on the members' psychological and human factors for the popularization of rock music, but I will apply the environmental factors that each member has been born and lived in, as well as the factors of family relations, such as parents. Queen is a band that has performed throughout the world for about 20 years, from the early 1970s to the birth and disappearance of a rock group. In sum, the four members of Queen, who have strong personalities, showed various musical possibilities by combining completely different genres such as acafella, ballad, opera and hard rock, depending on their taste and imagination, and achieved legendary fame that transcended generations by displaying excellent skills in communicating with the public. The four personality and characters, the rock group Queen and its main vocal Freddie Mercury, were the feet of association calculated by correlation from internal to external influences.