• Journal of the Korean Institute of Gas
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• v.23 no.6
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• pp.90-96
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• 2019

Natural gas has been regarded as one of major alternative fuels, because of the increment of mining shale gas and supplying PNG(Pipeline Natural Gas) from Russia. Thus, it needs to broaden the usage of natural gas as the increasing its supplement. In this situation, application of natural gas on the transport area is a good suggestion to reduce exhaust emissions such as CO₂(carbon dioxides) and soot from vehicles. For this reason, natural gas can be applied to SI(spark ignition) engines due to its anti-knocking and low auto-ignitibility characteristics. Recently, since turbocharged SI engine has been widely used, it needs to apply natural gas on the turbocharged SI engine. However, there is a major challenge for using natural gas on turbocharged SI engine, because it is hard to make natural gas direct injection in the cylinder, while gasoline is possible. As a result, there is a loss of fresh air when natural gas is injected by MPI (multi-point injection) method under the same intake pressure with gasoline-fueled condition. It brings the power reduction. Therefore, in this research, intake pressure was increased by controling the turbocharger system under natural gas-fueled condition to improve power output. The goal of improved power is the same level with that of gasoline-fueled condition under the maximum torque condition of each engine speed. As a result, the maximum power levels, which are the same with those of gasoline-fueled conditions, with improved brake thermal efficiency could be achieved for each engine speed (from 2,000 to 6,000 rpm) by increasing intake pressure 5-27 % compared to those of gasoline-fueled conditions.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05b
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• pp.106.2-132
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• 2002

형질전환 (유전자 결핍; Knockout) Min 마우스를 이용하여 대장암 발생에서 배추, 양배추 주성분인 indole-3-carbinol (I3C)의 대장암 예방효과를 규명하고자 하였다. 실험동물로는 C57BL/6J-Apc$^{min/+}$(Min 마우스)계의 5내지 6주령의 수컷 이형접합체 형질전환 마우스 70마리와 C57BL/6J계의 동일 산자, 동일 주령의 수컷 wildtype 비형질전환 마우스 10kfl를 The Jackson Laboratory 사 (Bar harber, ME, USA)로부터 직접 구입하였다. C57BL/6J-Apc$^{min/+}$계 수컷 이형접합체 형질전환 (Min)마우스 70마리를 각 군 20내지 25마리씩 세군으로 나누었다. Group 1에는 20마리, Group 2에는 25마리, Group 3에는 25마리를 배치하고, I3C 투여 실험군 (Group 1과 2)에는 실험시작시에 AIN-76A 분말사료에 I3C가 각각 100 및 300ppm이 함유되도록 조제하여 공급하였다. 그리고 실험군(Group 3)에는 실험시작부터 종료시까지 AIN-76A 정제고형사료(Teklad사, WI, USA)를 자유로이 급이하였다. 각군간의 체중, 사료 및 음수소비량을 매 2주마다 측정하였고, 10주간 (16주령)의 실험종료시에는 최종체중과 간장, 신장, 비장 등의 장기무게를 측정하여 상대장기 무게비를 산출하였다. 대조군으로서 C57BL/6J계의 동일 산자, 동일 주령의 수컷 wildtype 비형질전환 마우스 10마리는 같은 조건의 사육실에서 AIN-76A 정제고형사료를 33주간 자유로이 급이하였다. 실험동물은 부검전에 하룻밤 동안 절식하고 이산화탄소 흡입 마취하에서 흉대동맥을 절단하여 방혈하고 각 장기(심장, 폐, 위)를 적출하여 생리심염수에 넣어 장기무게를 측정하고 포르말린에 고정하였다. 소장과 대장의 검사를 위하여 위의 식도부위와 직장을 실로 결찰하여 적출하고 생리심염수를 주입하여 팽창시켜, 십이지장, 공장, 및 회장, 그리고 대장으로 나누어 여과지에 펼친 후 포르말린에 고정하였다. 소장과 대장은 육안 및 자동 영상분석길ㄹ 이용한 분석이 끝난 후에 각 부위별로 4-6개의 절편을 작제하여 포르말린에 재고정하고, 통상적인 조직처리과정, 파리핀 포매 및 3-4$\mu$m 두께의 조직절편을 제작하여 H&E 염색을 실시하여 현미경으로 검경하였다. 약 1주일간의 포르말린 고정이 끝난 소장 및 대장을 부위별, 별 종양개수 및 분포를 자동영상분석기(Kontron Co. Ltd., Germany)로 분석하였다. 체의 변화, 장기무게, 사료소비량 및 마리당 종양의 개수에 대한 통계학적 유의성 검증을 위하여 Duncan's t-test로 통계처리 하였고, 종양 발생빈도에 대하여는 Likelihood ration Chi-square test로 유의성을 검증하였다. C57BL/6J-Apc$^{min/+}$계 수컷 이형접합체 형질전환 마우스에 AIN-76A 정제사료만을 투여한 대조군의 대장선종의 발생률은 84%(Group 3; 21/25례)로써 I3C 100ppm 및 300ppm을 투여한 경우에 있어서는 각군 모두 60%(Group 1; 12/20 례, Group 2; 15/25 례)로 감소하는 경향을 나타내었다. 대장선종의 마리당 발생개수에 있어서는 C57BL/6J-Apc$^{min/+}$계 수컷 이형접합체 형질전환 마우스에 AIN-76A 정제사료만을 투여한 대조군은 1.40$\pm$0.24(100%)에 비하여 I3C 저농도 투여 실험군(Group 1; 0.85$\pm$0.23; 61%, P<0.01), 그리고 I3C 고농도 투여 실험군(Group 2 ; 1.32$\pm$0.29 ; 94%)의 순으로 감소하였다. 선종의 크기별 종양의 발생개수의 분포에 있어서 I3C 저농도 투여 실험군에 있어서는 선종의 크기가 3mm이하의 수가 현저하게 감소하였다. C57BL/6J-Apc$^{min/+}$계 수컷 이형접합체 형질전환 마우스에 AIN-76A 정제사료만을 투여한 대조군의 부위별 소장선종의 발생수는 십이지장부위를 제외하고 각 군에서 유의한 변화는 관찰되지 않았다. 십이지장 종양의 발생개수에서만 I3C 저농도 투여 실험군(Group 1 ; 3.11$\pm$0.85)이 대조군 (Group 3: 1.48$\pm$0.35) 및 I3C 고농도 투여 실험군(Group 2: 1.56$\pm$0.47)에 비하여 유의성 있게 증가하였다. (P<0.05). 따라서 I3C은 소장에서는 암예방 효과가 뚜렷하지 않으나, 대장에 대한 암에방 효과가 있을 것으로 생각된다. 소장 및 대장을 제외한 간장, 신장, 비장, 심장, 폐 그리고 위 등의 기타 장기에서의 조직병리학적 변화는 관찰되지 않았다. 소장 및 대장의 종양은 선종(polyps)으로 관찰되었다. 지난 10여년간 형질전환 및 유전자 결핍 실험동물의 종류가 기하 급수적으로 증가하여 이용되고 있다. 가족성 대장 선종성 용종증(FAP)의 대표적인 모델로 이용되고 있는 C57BL/6J-Apc$^{min/+}$계 수컷 이형접합체 형질전환 마우스를 사용하여 배추나 양배추의 주요성분인 Indole-3-carbinol(I3C)의 대장암 예방효과가 있는지를 검색하여 본 결과 AIN-76A정제사료만을 투여한 대조군의 대장선종의 발생률 84%에 비하여 I3C 100 및 300ppm을 투여한 실험군에 있어서 각군 모두 60%로서 감소하는 경향을 나타내었으며, 대장선종의 마리당 발생개수에 있어서는 대조군의 1.40$\pm$1.041를 100%로 환산하였을 경우 I3C 저농도 및 고농도 투여 실험군에서는 각각 약 61%와 94%를 나타내여 감소하였다. 특히 대장선종의 크기별 분포에 있어서 선종의 크기가 3mm이하의 수가 현저하게 감소하였다. 따라서 저농도 I3C의 투여는 실험적 유전성 가족성 대장 선종성 용종증 모델에 있어서 어느정도 암 예방효과가 있는 것으로 생각된다. 그러나 소장 선종의 발생에는 별 영향이 없는 것으로 생각된다. 그러나 본 실험에 사용된 C57BL/6J-Apc$^{min/+}$계 수컷 이형접합체 형질전환 마우스는 실험개시 시점이 7내지 8주령이 경과하여 이미 태생기부터 소장 및 대장의 선종 발생이 진행되어 온 것을 감안하고 특히 비스테로이드계 항염증 소염제(NSAIDS)와 같은 강력한 COX-2억제제가 아님을 고려하면, 상당한 선종의 발생을 억제할 수 있는 가능성이 매우 높다고 생각한다. 또한 이제까지 배추나 양배추 성분의 복합성분들에 대한 실험적 대장암 모델에서의 촉진효과 등에 대한 보고들이 있어 온 점을 고려할 때 위암(Kim 등, 1994) 간암(Kim 등, 1994), 유방암(Grubbs, 등, 1995; Bradlow 등, 1995)에 대한 예방효과가 있을 것으로 생각된다. 앞으로 이러한 종양조직내에서의 COX-2 및 iNOS mRNA와 단백질의 발현정도를 분자병리학적으로 연구중에 있으며, 향후 십자화과식물 성분인 indole-3-carbinol이 마우스뿐 만 아니라 랫드의 화학발암물질에 의한 대장종양에 대한 억제효과 있는지 연구 필요가 있다. Min 마우스와 같은 형질 전환(유전자결핍;knockout) 실험동물을 이용한 새로운 중기 발암성 시험범의 확립을 통한 각종 환경 유해물질의 발암성 유무 및 COX-2 억제작용이 있는 식품인자의 암예방 후보물질을 체계적으로 검색하는데 유용하게 활용될 수 있을 것으로 생각한다.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.625-636
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• 2011

The purpose of this study was to evaluate the relationship between bone health and sodium intake in female university students using a dish frequency questionnaire (DFQ 125), anthropometric checkups, food records for 3 days, and ultrasound measurement of calcaneus bone mineral density. Subjects were divided into two groups: normal (n=196) and osteopenia (n=52). There were no significant differences in age or height between the two groups. The average weight, body mass index, and body fat in the normal group were significantly higher than in the osteopenia group. The sodium intake of DFQ was positively correlated with the sodium intake of 3 days of dietary records (p=0.0003). There were no significant differences in the sodium intake between the two groups from DFQ. The dishes were ranked by sodium intake: kimchies were 17.68%, noodles and mandu were 16.36%, stews were 13.69%, main dishes such as meat, egg, and beans were 11.47%, and fish and shellfish were 11.07%. The frequency of eating noodles and mandu (p=0.0116), stews (p=0.0008), kimchies (p=0.0482), fish and shellfish (p=0.0362), vegetables (p=0.0064) and seasoning (p=0.0347) were negatively associated with bone mineral density. Bone health was not significantly different with increasing quartiles of sodium intake. As excessive sodium intakes may indirectly affect bone mineral density, these results suggest that to prevent osteoporosis, university students needed to be more educated about diets containing less sodium through nutrition education programs.

• Journal of fish pathology
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• v.25 no.3
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• pp.263-270
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• 2012

This study surveyed for the prevalence of parasites, bacteria and viruses in four fish species, olive flounder (Paralichthys olivaceus), red sea bream (Pagrus major), black sea bream (Acathopagrus schlegeli) and black rockfish (Sebastes schlegeli) in 2010. The survey was aimed to compare the pathogens detected from wild and cultured fish for an epidemiological study. Anisakis sp. was predominantly detected from wild olive flounder and red sea bream (58.6% and 41.7% respectively), but not from the cultured fishes, suggesting anisakid infection is rare in cultured fish. The wild fish get in contact with the anisakids through their prey such as small fishes or crustaceans which carry the anisakids; whereas the cultured fish are fed with formulated feed, free of anisakids. Bacterial detection rates from the wild fishes examined in the study were lower than those of cultured fishes. Vibrio sp. dominated among detected bacterial population in cultured olive flounder (18%). Since vibriosis is known as a secondary infection caused by other stressful factors such as parasitic infections, handling and chemical treatment, it seems that cultured olive flounder are exposed to stressful environment. Viruses diagnosed in the study showed difference in distribution between wild and cultured fishes; hirame rhabdovirus (HRV) (0.1%) and lymphocystis disease virus (LCDV) (3.9%) were detected in the cultured olive flounder, but not in the wild fish, and marine birnavirus (MBV) (1.7%) and red sea bream iridovirus (RSIV) (3.2%) were detected from the wild and cultured red sea bream, respectively. From the survey conducted, it can be concluded that even though some pathogens (Trichodina sp., Microcotyle sp., etc.) are detected from both the wild and cultured fish, pathogens such as Anisakis sp., Vibrio sp. and LCDV showed difference in distribution in the wild and cultured host of same fish species and this can be attributed to their environmental condition and feeding.

• Journal of Venture Innovation
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• v.4 no.2
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• pp.57-75
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• 2021

KHNP's shared growth activities are based on such public good. Reflecting the characteristics of a comprehensive energy company, a high-tech plant company, and a leading company for shared growth, it presents strategies to link performance indicators with its partners and implements various measures. Key tasks include maintaining the nuclear power plant ecosystem, improving management conditions for partner companies, strengthening future capabilities of the nuclear power plant industry, and supporting a virtuous cycle of regional development. This is made by reflecting the specificity of nuclear power generation as much as possible, and is designed to reflect the spirit of shared growth through win-win and cooperation in order to solve the challenges of the times while considering the characteristics as much as possible as possible. KHNP's shared growth activities can be said to be the practice of the spirit of the times(Zeitgeist). The spirit of the times given to us now is that companies should strive for sustainable growth as social air. KHNP has been striving to establish a creative and leading shared growth ecosystem. In particular, considering the positions of partners, it has been promoting continuous system improvement to establish a fair trade culture and deregulation. In addition, it has continuously discovered and implemented new customized support projects that are effective for partner companies and local communities. To this end, efforts have been made for shared growth through organic collaboration with partners and stakeholders. As detailed tasks, it also presents fostering new markets and new industries, maintaining supply chains, and emergency support for COVID-19 to maintain the nuclear power plant ecosystem. This reflects the social public good after the recent COVID-19 incident. In order to improve the management conditions of partner companies, productivity improvement, human resources enhancement, and customized funding are being implemented as detailed tasks. This is a plan to practice win-win growth with partner companies emphasized by corporate social responsibility (CSR) and ISO 26000 while being faithful to the main job. Until now, ESG management has focused on the environmental field to cope with the catastrophe of climate change. According to KHNP is presenting a public enterprise-type model in the environmental field. In order to strengthen the future capabilities of the nuclear power plant industry as a state-of-the-art energy company, it has set tasks to attract investment from partner companies, localization and new technologies R&D, and commercialization of innovative technologies. This is an effort to develop advanced nuclear power plant technology as a concrete practical measure of eco-friendly development. Meanwhile, the EU is preparing a social taxonomy to focus on the social sector, another important axis in ESG management, following the Green Taxonomy, a classification system in the environmental sector. KHNP includes enhancing local vitality, increasing income for the underprivileged, and overcoming the COVID-19 crisis as part of its shared growth activities, which is a representative social taxonomy field. The draft social taxonomy being promoted by the EU was announced in July, and the contents promoted by KHNP are consistent with this, leading the practice of social taxonomy

• Journal of Intelligence and Information Systems
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• v.24 no.3
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• pp.67-88
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• 2018

Until recently, as we recognize the significance of sustainable growth and competitiveness of small-and-medium sized enterprises (SMEs), governmental support for tangible resources such as R&D, manpower, funds, etc. has been mainly provided. However, it is also true that the inefficiency of support systems such as underestimated or redundant support has been raised because there exist conflicting policies in terms of appropriateness, effectiveness and efficiency of business support. From the perspective of the government or a company, we believe that due to limited resources of SMEs technology development and capacity enhancement through collaboration with external sources is the basis for creating competitive advantage for companies, and also emphasize value creation activities for it. This is why value chain network analysis is necessary in order to analyze inter-company deal relationships from a series of value chains and visualize results through establishing knowledge ecosystems at the corporate level. There exist Technology Opportunity Discovery (TOD) system that provides information on relevant products or technology status of companies with patents through retrievals over patent, product, or company name, CRETOP and KISLINE which both allow to view company (financial) information and credit information, but there exists no online system that provides a list of similar (competitive) companies based on the analysis of value chain network or information on potential clients or demanders that can have business deals in future. Therefore, we focus on the "Value Chain Network System (VCNS)", a support partner for planning the corporate business strategy developed and managed by KISTI, and investigate the types of embedded network-based analysis modules, databases (D/Bs) to support them, and how to utilize the system efficiently. Further we explore the function of network visualization in intelligent value chain analysis system which becomes the core information to understand industrial structure ystem and to develop a company's new product development. In order for a company to have the competitive superiority over other companies, it is necessary to identify who are the competitors with patents or products currently being produced, and searching for similar companies or competitors by each type of industry is the key to securing competitiveness in the commercialization of the target company. In addition, transaction information, which becomes business activity between companies, plays an important role in providing information regarding potential customers when both parties enter similar fields together. Identifying a competitor at the enterprise or industry level by using a network map based on such inter-company sales information can be implemented as a core module of value chain analysis. The Value Chain Network System (VCNS) combines the concepts of value chain and industrial structure analysis with corporate information simply collected to date, so that it can grasp not only the market competition situation of individual companies but also the value chain relationship of a specific industry. Especially, it can be useful as an information analysis tool at the corporate level such as identification of industry structure, identification of competitor trends, analysis of competitors, locating suppliers (sellers) and demanders (buyers), industry trends by item, finding promising items, finding new entrants, finding core companies and items by value chain, and recognizing the patents with corresponding companies, etc. In addition, based on the objectivity and reliability of the analysis results from transaction deals information and financial data, it is expected that value chain network system will be utilized for various purposes such as information support for business evaluation, R&D decision support and mid-term or short-term demand forecasting, in particular to more than 15,000 member companies in Korea, employees in R&D service sectors government-funded research institutes and public organizations. In order to strengthen business competitiveness of companies, technology, patent and market information have been provided so far mainly by government agencies and private research-and-development service companies. This service has been presented in frames of patent analysis (mainly for rating, quantitative analysis) or market analysis (for market prediction and demand forecasting based on market reports). However, there was a limitation to solving the lack of information, which is one of the difficulties that firms in Korea often face in the stage of commercialization. In particular, it is much more difficult to obtain information about competitors and potential candidates. In this study, the real-time value chain analysis and visualization service module based on the proposed network map and the data in hands is compared with the expected market share, estimated sales volume, contact information (which implies potential suppliers for raw material / parts, and potential demanders for complete products / modules). In future research, we intend to carry out the in-depth research for further investigating the indices of competitive factors through participation of research subjects and newly developing competitive indices for competitors or substitute items, and to additively promoting with data mining techniques and algorithms for improving the performance of VCNS.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.6
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• pp.744-757
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• 2012

This study was designed to obtain basic data for the globalization of Korean food and the expansion of food exports through contract foodservices. A survey of dietary habits and attitudes toward school foodservices was given to students in three American international schools served by a domestic contract foodservice management company located in Seoul and Gyeonggi area. The results showed an average of three meals taken daily 3.39 times for male students and 2.95 times for female students and the time required for a meal was about 24~26 minutes. The average breakfast frequency was 5.10 times(4.59 times for male students and 5.35 times for female students) and many students reported skipping breakfast due to a lack of time. The average weekly frequency of dining out was 1.78 times(2.15 times for male students and 1.60 times for female students). In all schools, irrespective of gender and grade, students responded that a desire for snacking was 'why they want to have cookies', and snacking hours were frequently listed as 'between noon and evening'. Many also responded that an unbalanced diet is the reason some snacks are 'not to their taste'. Overall, students were highly satisfied with the foodservice menu, although there was a significant difference in what was considered proper food temperature, proper food seasoning, suitable amounts of food, and freshness of food. Male and female students were specifically highly satisfied with the 'freshness of food materials' and 'variety of menu' respectively. Overall, all students were highly satisfied with the foodservice, including the 'cleanliness of tables and trays'.

• Korean Journal of Soil Science and Fertilizer
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• v.15 no.1
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• pp.49-50
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• 1982

The objective of this paper is to review the changes in fertilizer use pattern and to discuss some aspects of the fertilizer development in Korea. Fertilizer consumption in Korea have steadily increased to triple the application rates of N, P and K during the 15 years from 1965 to 1980, and Korea became one of the countries which apply fertilizers at the highest rate. The ratio of N: $P_2O_5$: $K_2O$ in fertilizer consumption changed from 55.4 : 31.4 : 13.1 in 1965 to 54.0 : 23.8 : 22.2 in 1980. It can be said that Korean farmers practise a balanced fertilization at least in view of fertilizer consumption as compared to other developing countries. However, differences in soil properties, crops, and climate varying as region were not reflected on fertilization. In the technological development of fertilizer, the chemical form and composition of the fertilizer as well as the suitability to the specific crops must be taken into consideration for the efficient use of fertilizers. Although organic fertilizers and manure are accepted as minor element suppliers, it is necessary to add minor elements into chemical fertilizers on the industrial process. Industrial waste may be used for the agricultural production as a measure of pollution control providing careful study on the waste.