• 대한한의학회지
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• 제29권1호
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• pp.106-116
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• 2008

Objectives : Peroxynitrite $(ONOO^-)$, superoxide anion radical $({\cdot}O_2^-)$ and nitric oxide (NO) are cytotoxic because they can oxidize several cellular components such as proteins, lipids and DNA. They have been implicated in the aging processes, and age-related diseases such as Alzheimer's disease, rheumatoid arthritis, cancer and atherosclerosis. The aim of this study was to investigate the $ONOO^-$, NO, and $({\cdot}O_2^-)$ scavenging and anti-inflammatory activities of Mori Fructus in ob/ob mice. Methods : Mice were grouped and treated for 5 weeks as follows. Both the normal lean (C57/BL6J black mice) and control obese (ob/ob mice) groups received the standard chow. The experimental groups were fed a diet of chow supplemented with 7.5, 15 and 30 mg Mori Fructus per 1 kg of body weight for 14 days. For this study, the fluorescent probes, namely 2',7'-dichlorodihydrofluorescein diacetate (DCFDA), 4,5-diaminofluorescein (DAF-2) and dihydrorhodamine 123 (DHR 123) were used. Western blotting was performed using anti-phospho $I{\kappa}B-\alpha$, anti-IKK-$\alpha$, anti-NF-${\kappa}B$ (p50, p65), anti-COX-2 and anti-iNOS respectively. Results : Mori Fructus inhibited the generation of $ONOO^-$, NO and $({\cdot}O_2^-)$ in the lipopolysaccharide (LPS)-treated mouse kidney postmitochondria in vitro. The generation of $ONOO^-$, NO and $({\cdot}O2^-)$ were inhibited in the Mori Fructus-administered ob/ob mice groups. The GSH/GSSG ratio decreased in the ob/ob mice, whereas they improved in the Mori Fructus-administered groups. Mori Fructus inhibited the expression of phospho $I{\kappa}B-\alpha$, IKK-$\alpha$, COX-2, iNOS genes, and thereby the activation of NF-$I{\kappa}B$. Conclusions : These results suggest that Mori Fructus is an effective $ONOO^-$, $({\cdot}O_2^-)$ and NO scavenger, and therefore it might be a potential therapeutic drug against the inflammation process and inflammation-related diseases.

• 동력기계공학회지
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• 제19권2호
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• pp.49-56
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• 2015

As an alternative fuel that can be used in SI engine, LPG is one of clean fuels with larger H/C ratio compared to gasoline, low $CO_2$ emission, and small amount of pollutants such as sulfur compounds. When LPG is used in spark ignition engine, volumetric efficiency of the engine can be improved and pumping loss can be reduced by performing direct injection into the combustion chamber instead of port fuel injection. LPG-DI engine allows for lean combustion and stratified combustion under low load. In case of stratified combustion, air fuel ratio can be greatly increased compared to theoretic mixture ratio combustion. Improved thermal efficiency of the engine and reduced pumping loss can be expected from stratified combustion. Accordingly in this study, an experimental apparatus for visualization was designed and manufactured to study the combustion process of LPG after injection and ignition, intended to examine ignition probability and combustion characteristics of spark ignition direct injection(SIDI) LPG fuel. Ambient pressure, ambient temperature and fuel injection pressure were found as important variables that affect ignition probability and flame propagation characteristics of LPG-air mixture. Also, it was verified that the injected LPG fuel can be directly ignited by spark plug under appropriate ambient conditions.

• 디지털콘텐츠학회 논문지
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• 제13권3호
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• pp.359-371
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• 2012

최근 커피 시장의 규모는 급속도로 커지고 커피 산업도 빠르게 성장하고 있다. 그 결과 커피 교육 기관이 다양한 형태로 급증하고 있으나 대부분의 수업이 실습에 편중되어 있는 경우가 많아 이론 수업의 기틀을 마련하고 커피 교육을 학문으로 체계화 하는 노력이 필요하다. 이에 커피 교육에 관한 연구 조사 및 커피 교사 학습자의 요구 분석을 토대로 교육용 디지털 콘텐츠를 제작하였다. 기존의 교육용 콘텐츠와는 차별화하여 명확한 교수 학습 방법, 교수 전략을 개발한 후 시행하였다. 또한 전문적인 시각 언어를 바탕으로 커피 추출 시 일어나는 물리적 화학적 현상을 3D 애니메이션 프로그램으로 시뮬레이션 하였다. 즉, 본 연구의 교육용 콘텐츠 제작의 전반적인 과정은 현장 교사 학습자의 요구조사, 교육학 전공자의 교수전략, 콘텐츠 제작자의 상호연계에 의해 이뤄졌다. 본 콘텐츠를 커피 원리에 대한 이론 수업에 적용한 결과 학습자의 집중도, 흥미성 및 학습 동기 유발에 효과적이었다. 교사들은 과학적 현상에 대한 학습자의 이해에 긍정적인 영향을 끼치는 것으로 평가하였다.

• 한국건설관리학회논문집
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• 제8권3호
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• pp.57-65
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• 2007

작업성취율(Percent of Plan Completed: PPC) 도입을 통한 효과는 선진 건설 사례들을 통해 검증되고 있으나, 우리 건설현업에서는 이에 대한 적용사례가 없다 본 연구는 외국에서 작업성취율을 적용한 사례를 분석하고 이를 우리 건설현업에서의 공정관리체계와 비교함으로써 작업성취율 활용을 위한 공정관리체계를 제시하는 것을 목표로 하였다. 외국 사례와 국내 공정관리체계를 비교함에 있어 3주 미래 작업계획단계의 예비작업목록 작성과 제반요건분석, 1주 작업 단계의 실패원인 분석과 작업성취율 측정 등의 관리 도구를 선정하였고 이틀을 대상으로 LPS(Last Planner System)와 국내의 공정관리현황을 비교 분석함으로써 차이점을 분석하고 작업성취율 활용을 위한 추가 공정관리절차출 제시하였다. 또한, 국내 건설 전문가들에게 설문 및 면담을 통해 본 연구에서 제시한 공정관리체계의 현장 적용성 검토를 실시하였다.

• 한국건설관리학회논문집
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• 제7권4호
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• pp.146-153
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• 2006

라스트 플래너는 린 건설의 핵심적인 생산관리 이론으로 공정간 신뢰도를 향상시키는 것에 목적을 두고 있다. 해외의 여러 연구기관 및 기업체들이 린 건설의 이론 및 라스트 플래너 방법을 사용하여 많은 사례연구를 수행하였다. 최근 국내의 건설 업체 및 연구기관에서 린 건설 및 라스트 플래너 방법이 소개되었고, 이에 대한 연구 및 도입에 많은 노력을 기울이고 있다. 그러나 국내 건설업체가 라스트 플래너를 공정관리 방법으로 도입함에 있어 기존의 공정관리 방법과의 상이성, 조직 구성의 차이, 문화적 차이 등으로 인한 많은 어려움에 직면하고 있다. 또한, 공사시공의 상당부분을 협력업체의 외주에 의존하는 현실에서 협력업체가 라스트 플래너 공정관리의 주체로 참여하지 않고는 효과적인 라스트 플래너를 수행하는데 있어 어려움이 있다. 본 연구는 국내의 건설업체의 토목공사 현장을 대상으로 라스트 플래너 방법을 수행하였다. 본 연구에서는 3개월간 라스트 플래너 방법 수행하면서 획득한 결과를 토대로 수행연구 분석하였고, 라스트 플래너 방법을 수행하는데 있어 영향을 미칠 수 있는 생산외적 요소들에 대하여 서술하였다.

• 한국연소학회지
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• 제18권2호
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• pp.32-41
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• 2013

This study presents both experimental and numerical investigation of ignition delay time of n-heptane and n-butanol binary fuel. The $O_2$ concentration in the mixture was set to 9-10% to make high exhaust gas recirculation( EGR) rate condition which leads low NOx and soot emission. Experiments were performed using a rapid compression machine(RCM) at compressed pressure 20bar, several compressed temperature and three equivalence ratios(0.4, 1.0, 1.5). In addition, a numerical study on the ignition delay time was performed using CHEMKIN codes to validate experimental results and predict chemical species in the combustion process. The results showed that the ignition delay time increased with increasing the n-butanol fraction due to a decrease of oxidation of n-heptane at the low temperature. Moreover, all of the binary fuel mixtures showed the combustion characteristics of n-heptane such as cool flame mode at low temperature and negative-temperature-coefficient(NTC) behavior. Due to the effect of high EGR rate condition, the operating region is reduced at lean condition and the ignition delay time sharply increased compared with no EGR condition.

• Journal of Nutrition and Health
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• 제46권4호
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• pp.307-314
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• 2013

본 연구에서는 레스베라트롤이 당뇨병 및 비알코올성 지방간 질환 개선 효과를 가지는지를 규명하기 위해 고지방 식이 유도 비만 쥐를 대상으로 레스베라트롤을 4주간 osmotic pump를 사용하여 공급한 후 정상대조군과 고지방식이 제공 비만군과 비교 분석하였고 그 결과는 다음과 같다. 1) 고지방식이 유도 비만 쥐를 대상으로 8 mg/kg/day의 레스베라트롤을 4주간 처리한 결과 체중 변화, 간 조직 중량, 식이 섭취량에 영향을 미치지 않았다. 2) 레스베라트롤은 공복 혈당, 혈청 내 인슐린, 중성지방, 총 콜레스테롤 농도를 낮추었고, 인슐린 작용을 촉진시키는 혈청 아디포넥틴 수준을 개선시켰다. 또한, 고지방식이에 의해 높아진 간 조직 내 중성지방과 총콜레스테롤 농도를 낮추어 레스베라트롤이 지방간 개선 효과를 가질 수 있음을 제안하였다. 3) 자가포식의 표지인자인 autophagosome 생성과 LC3-II 형성 분석 결과, 고지방식이에 의해 과도한 자가포식이 유도되었음을 확인하였다. 레스베라트롤 처리는 이중막을 가지는 autophagosome 생성과 LC3-II 형성을 감소시켜 고지방식이에 의해 유도된 과도한 자가포식을 억제시킴을 보여주었다. 결론적으로 고지방식이와 함께 레스베라트롤을 제공하는 것은 당뇨병과 비알코올성 지방간 질환 관련 대사 인자들을 개선시키고, 이는 간에서의 자가포식 조절과 관련이 있다고 제안한다.

• 디지털융복합연구
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• 제16권11호
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• pp.221-230
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• 2018

기업의 창업가들과 경영자들은 글로벌 대기업들에 의해 지배되고 있는 산업들에서 성공하기 위해 필요한 규모 및 능력을 달성하기 위해서 협력업체들과의 확장된 네트워크를 잘 이용할 줄 알아야 한다는 사실을 목격하게 된다. 기업의 경영자들은 간소하지만 민첩한 기업을 만들고자 한다면, 그들은 어떻게 기업의 조직구조 모델이 운영효율성, 유연성에 영향을 미치게 되는지, 그리고 어떻게 기업 조직을 기업환경과 전략(기회와 위협을 감지하고 대응할 수 있는)에 맞게 조정해야 하는지를 이해해야 한다. 본 연구는 요즘처럼 빠르게 변하고 불확실한 기업 환경에서 생존하고 번창할 수 있는 기업을 만들기 위해 필요한 역량들을 검토한다. 본 논문에 제시된 것 들은 빠르게 변하는 글로벌 경제의 수요에 대처하려 했던 수백 명의 경영자들과 기업창업자들의 지난 20년 동안의 노력의 결과들이다[1]. 본 연구의 결과는 정보기술(IT)이 기업의 성공을 위해 필요한 역량 및 조직구조를 개발하는데 있어서 필요한 가이드라인을 제공한다. 본 연구는 계량적인 연구 모델을 제시하지 못하는 한계점을 가지고 있으나, 최근의 정보기술 환경에서 기업들이 조직의 구조를 설계하는데 있어 고려해야할 점들과 지침을 제공하는 것이 연구의 목적이다.

• 한국정보시스템학회지:정보시스템연구
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• 제30권4호
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• pp.173-202
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• 2021

Purpose This study explored overall phenomena in context such as YouTube channel operation, strategy, and profit generation through interviews with two research participants who started their own businesses and are recognized as influencer on YouTube and analysis of viewer responses to uploaded contents. With the explosive growth of YouTube content provision and use, previous studies on YouTube are only being conducted individually on YouTube's content, influence, and content providers, so it is need to explore YouTube channel operations and the effect of revenue generation in context from an integrated perspective. Therefore, the purpose of this study is to present an integrated model that provides a specific process by contextually linking the factors and results influencing YouTube channel operation and revenue generation phenomena to individuals and companies who are trying to operate YouTube channels for the first time. Design/methodology/approach This study systematized and structured the overall phenomena in context such as YouTube channel operation, communication strategy, effect on revenue generation, and YouTube channel operation results by selecting interview subjects and collecting data through interviews, and analyzing viewer reactions (likes, comments, etc.). Due to the lack of previous studies exploring integrated phenomena, research analysis used Strauss & Corbin (1998)'s grounded theory approach, which presented inductive research methods to discover new theories by structuring concepts and categories based on detailed observations and information provided by interviewees. Findings The academic implication of this study is that while previous studies are conducted as individual studies on YouTube's content, influence, and content providers in the current situation where YouTube content provision and use are exploding, it integrally explores and presents an integrated model throughout the process. In addition, taking into account the lack of previous studies, it can be found in the aspect of using the grounded theory approach, an inductive theory approach that establishes a new theory. The practical implications can be found in that it presented practical directions to beginners who want to start operating YouTube channels by identifying operational preparations, communication strategies with viewers, and response management strategies.

• 기술혁신연구
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• 제5권2호
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• pp.1-21
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• 1997

The objective of this paper is to think about what structural reforms of the Korean government S&T development management system might be. Korean society is currently experiencing a drastic socio-economic transformation. The results of this transformation should be reflected on the determining process of the directions and breadths of structural reforms of government S&T development management system. Because the government system design will be based on the premises of socio-economic conditions under which administrative activities perform and also this socio-economic changes can influence on changes of the premises of government management system design. Moreover, S&T development management system is a subsystem of government system so that the directions of structural reform of those subsystems should be considered in the broad framework changes in the development management system of the government. For the last forty years, the Korean government S&T development management system has been based on the premises including transformation from an agrarian society to an industrial society, authoritarianism and centrally controlled institutions, and exteremely small portions of private investments for science and thechonology R & D of the total. Recently, however, the premises of Korean government S&T development management system have rapidly changed. the characteristics of these changes are including tranformation from an industrial society to a knowledge and information intensive society, globalization, localization, and relatively large portion of private investments for science and technology R & C of the total. The basis of government reforms in Korea was the realization of the performances and values through the enhancement of national competitive capacity, attainment of lean government, decentralization and autonomy. However, the Korean government has attached a symbolic value of strategic organizations representing strong policy intentions of government for the science and technology based development. Most problems associated with the Korean government S&T development management system have grown worse during 1990s. Many people perceive that considerable part of this problem was generated because the government could not properly adapt itself to new administrative environment and the paradigm shift in its role. First of all, the Korean government S&T development management system as a whole failed to develop an integrated vision under which processes in formulating science and thechology development goals and developing consistent government plans concerning science and technology development are guided. Second, most of the local governments have little organizational capacity and manpowers to handle localized activities to promote science and technology in their regions. Third, the measure to coordinate and set priorities to invest resources for the development of science and technology was not effective. Fourth, the Most has been losing its reputation as the symbol of ideological commitment of the top policy maker to promote science and technology. Various ideas to reform government S&T development management system have been suggested recently. Most frequently cited ideas are as follow : (ⅰ)strengthen the functions of MoST by supplementing the strong incentive and regulatory measures; (ⅱ)create a new Ministry of Education, Science & Technology and Research by merging the Ministry of Education and the MoST; (ⅲ)create a new Ministry of Science & Technology and Industry ; and(ⅳ)create a National Science and Technology Policy Council under the chairmanship of the President. Four alternatives suggested have been widely discussed among the interested parties and they each have merits as well as weaknesses. The first alternative could be seen as an alternative which cannot resolve current conflicts among various ministries concerning priority setting and resource allocation. However, this alternatives can be seen as a way of showing the top policymaker's strong intention to emphasize science and technology based development. Second alternative is giving a strategic to emphasize on the training and supplying qualified manpower to meet knowledge and information intensive future society. This alternative is considered to be consistent with the new administrative paradigm emphasizing lean government and decentralization. However, opponents are worrying about the linkages and cooperative research between university and industry could be weakening. The third alternative has been adopted mostly in nations which have strong basic science research but weak industrial innovation traditions. Main weakness of this alternative for Korea is that Korean science and technology development system has no strong basic science and technology research traditions. The fourth alternative is consistent with new administrative paradigms and government reform bases. However, opponents to this alternative are worried that the intensive development of science and technology because of Korea's low potential research capabilities in science and technology development. Considerning the present Korean socio-economic situation which demands highly qualified human resources and development strategies which emphasizes the accumulations of knowledge-based stocks, I would like to suggest the route of creating a new Ministry of Education, Science & Technology and Research by intergrating education administration functions and science & technology development function into one ministry.