• Ocean and Polar Research
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• 제41권2호
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• pp.107-120
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• 2019

The frequency analysis of scientific terms using bibliographic information is a simple concept, but as relevant data become more widespread, manual analysis of all data is practically impossible or only possible to a very limited extent. In addition, as the scale of oceanographic research has expanded to become much more comprehensive and widespread, the allocation of research resources on various topics has become an important issue. In this study, the frequency analysis of scientific terms was performed using text mining. The data used in the analysis is a general-purpose scholarship database, totaling 2,878 articles. Hypoxia, which is an important issue in the marine environment, was selected as a research field and the frequencies of related words were analyzed. The most frequently used words were 'Organic matter', 'Bottom water', and 'Dead zone' and specific areas showed high frequency. The results of this research can be used as a basis for the allocation of research resources to the frequency of use of related terms in specific fields when planning a large research project represented by single word.

• 대한조선학회 특별논문집
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• 대한조선학회 2017년도 특별논문집
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• pp.105-108
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• 2017

Condensation is one of the common issues which we can easily see in everyday life. For example, the surface of glasses with cold water is easily moisturized. This wet surface gives us uncomfortable feeling and is sometimes dangerous because it is slippery. As the safety on working space is one of the most important issue on offshore project, condensation is also important matter to take care of with precaution. Since the bottom of vessel or offshore facility is submersed in the water, the risk of having condensate on the steel surface is getting higher because sea water temperature is normally lower than ambient temperature. And if there is any electric equipment or person working in that space, condensation is normally not allowed. The pontoon of semi-submersible drilling rig is such a space which is submersed, with electric and mechanical equipments and person working periodically. To prevent condensation in pontoon, study was conducted by checking several cases.

• 항공우주정책ㆍ법학회지
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• 제32권2호
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• pp.219-246
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• 2017

핵문제는 국제레짐(resime)의 지구화를 보여주는 좋은 예이다. 1945년 8월 일본에 최초로 핵폭탄이 투하되면서 핵무기가 인류를 절멸시킬 수 있다는 역사를 통해 평화에 대한 갈망은 더욱 절실해졌다. 자국의 안보를 위한 군비증강은 국제사회에서 자존의 문제이지만, UN헌장의 목적이기도 한 국제평화와 안전을 유지하기 위해 군축 또는 군비통제는 전 인류의 평화 실현과 직결된 가장 중요한 과제일 것이다. 오늘날 군축은 국제분쟁의 평화적 해결, 집단안전보장제도와 함께 국제평화와 안전을 유지 촉진하는 중요한 수단이다. 완전한 군축 실현이 항구적인 인류의 과제일 수는 있으나, NPT 서문에서 일반적이고 완전한 군축이 표현된 것처럼 국제사회는 완전 군축을 위한 노력을 천명하고 있다. 따라서 핵문제에 대한 국제레짐과 북한의 핵문제에 대한 주요 경과를 살펴봄으로써 핵문제의 지구화 현상을 소개하고, 핵 군축을 위한 국제사회의 노력을'인류의 공동유산'개념과 우주공간 평화이용위원회 및 핵무기의 통제를 중심으로 검토한 후, 대한민국과 국제법에 직결된 사안인 북한의 핵문제를 우주법 내지 군축법적인 관점에서 평가해 보고자 한다. 또한 북한의 핵문제를 위해서는 비확산 반확산정책과 함께 집단안전보장제도가 지속적으로 강조 시도되어야 할 것이다.

• Elastomers and Composites
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• 제56권4호
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• pp.234-242
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• 2021

The demand for truck bus radial (TBR) tires with enhanced fuel efficiency and wear resistance have grown in recent years. In addition, as the issue of particulate matter and air pollution increases, efforts are being made to reduce the generation of particulate matter. In this study, the properties of epoxidized natural rubber (ENR) containing a silica-friendly functional group were evaluated by considering it as a base rubber and varying the silica ratio in this binary filler system. The results showed that the wear resistance of the NR/BR blend compound decreased as the silica ratio increased. In contrast, the ENR/BR blend compound exhibited an increase in wear resistance as the silica ratio was increased. In particular, the ENR-50/BR blend compound showed the best wear resistance due to the presence of several epoxide groups. Furthermore, we observed that for tan 𝛿 at 60℃, higher epoxide content resulted in the higher T_g of the rubber, indicating a higher tan 𝛿 at 60℃. On the other hand, it was confirmed that increasing the silica ratio decreased the value of tan 𝛿 at 60℃ in all compounds. In addition, we measured the amount of wear particulate matters generated from the compound wear. These measurements confirmed that in the binary filler system, regardless of the filler type, the quantity of the generated wear particulate matters as the filler-rubber interaction increased. In conclusion, the silica filled ENR/BR blend compound exhibited the lowest generation of wear particulate matters.

• 한국환경복원기술학회지
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• 제21권3호
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• pp.99-110
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• 2018

Compared to yellow dust coming from China or particulate matter created naturally in spring due to Total Suspended Particulate(TSP), particulate matter in winter season have much more serious effect on human body as they penetrate cell membranes. Although such particulate matter are becoming a social issue, there are no concrete plans on how to reduce them. Air-purifying plants are limited in maintaining the indoor air quality of large area because it is usually difficult to quantify their performance. In order to improve this, a bio-filter that can be connected to air conditioner is suggested as an option. This study seeks to improve air conditioning model-based monitoring method for bio-filters from prior studies and objectify correlations between applied vegetation and growing environment into quantitative indicators. By doing so, this study seeks to provide criteria on plants applied to artificial soil-based vegetation bio-filters and basic information to set air-conditioning features. The study results confirmed significant tendency on the growing stability of each purifying plant in mechanical air-conditioning environment. Among three models selected for bio-filter vegetation models, epipremnum aureum showed high performance in quantitative indicators, including soil moisture, EC, and leaf temperature, etc., indicating that it would assure the highest growing stability in this test air-conditioning environment.

• 한국환경교육학회지:환경교육
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• 제18권1호
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• pp.70-81
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• 2005

The importance of classes aiming at enhancing students ability in problem solving and decision making has been being recognized as chances of individual citizen for taking part in social decision making processes. This study was intended to find whether teachers' opinion presentation have effects on students' decision making in a class introducing environmental issues. Total of 6 classes, 202 middle school students have participated in a series of experiments including 4 different environmental issues. Only two issues had been addresses in classes as experimental issues and other two issues not addressed as control issues. For each of the two experimental issues, the teacher researcher applied three different approaches to his students that included positive, negative, or no opinion. The results of this study can be summarized as follows; First, the results showed that students changed their decisions on environmental issues more frequently when dealing with those issues in a class than when not dealing with them. Second, as examining the relationship between patterns in which students make decisions and whether a teacher proposed his opinions or not, it is shown that the rates of students whose opinions is not changed nearly have no difference, while when teachers propose their opinions, it is shown that students who haven't yet chosen their positions easily make their decisions into pros or cons, compared with the opposite case. Third, the results of this study partly supported the third hypothesis that teachers opinion presentation would effect on decision-making of students. It was found that there has been a significant effect in the case of car free day system issue, but no statistically meaningful result in the case of no pets in the national park issue. However, in the issue of car free day system, it seems pretty clear that the students followed the direction of teachers' opinion no matter what it was pros or cons.

• 지식경영연구
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• 제18권3호
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• pp.101-124
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• 2017

Recently, 'happiness' has become a major issue of national level, exceeding the matter of personal issue. Especially, Korea has actually increased its GDP by focusing on the economic growth for decades, and now it has achieved the economic/technical development as an IT power. However, Korean people's satisfaction with life called 'happiness index' is moving back every year. Even though there have been continuous efforts to enhance the national happiness by mentioning it as an essential issue in the national level, there are not many researches related to it. This study drew measures to enhance happiness by extracting happiness factors and unhappiness factors of Korea through social network service. Especially, it aims to analyze, compare, and apply happiness factors and unhappiness factors of three countries such as the US, UK, and Brazil with higher happiness indexes than Korea. For this, through the topic modeling of text mining technique, postings including keywords about happiness and unhappiness were collected/analyzed from Twitter of Korea, the US, UK, and Brazil. The significance of this study is to discuss measures to increase happiness and to decrease unhappiness by mining/analyzing the actual public opinions about happiness and unhappiness in four countries like Korea, the US, UK, and Brazil by using the topic modeling. Through this, the quality of life of Korean people could be improved by suggesting measures to enhance happiness and to decrease unhappiness in the level of individual, family, society, and government.

• 한국언어정보학회지:언어와정보
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• 제1권
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• pp.227-276
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• 1997

There has been no nuanimous analysis of specific indefinites. It is still disputed even whether specificity is a matter of semantics of pragmatics. In this paper, I introduce some properties of specific indefinites, and explain them based on the meaning of specificity. Specificity intuitively means that the speaker or someone else in the context has some individual in mind, which is generally accepted among liguistics. The main issue is how to represent the meaning of 'have-in-mind'. I review some philosophical discusstions of cognitive contact and show that when the use of an expression involves 'have-in-mind', the expression is rigid designator in the belief of the agent who has an individual in mind. in the use of a specific indefinite, this applies only to the information state of the agent of 'have-in-mind'. To represent this asymmetry, I propose a new theory of dynamic semantics, in which a common ground consists of multiple information states, as many as the number of the participants in a conversation. Moreover, each information state is structured as a set of epistemic alternatives, which is a set of possible information states of a participant in the context. Based on this semantics, the properties of specific indefinites are explained.

• Journal of Preventive Medicine and Public Health
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• 제40권6호
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• pp.419-421
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• 2007

Objectives : The aim of this study was to introduce the concept of health inequalities, and to discuss the underlying assumptions and ethical backgrounds associated with the issue, as well as the theoretical and practical implications of health inequalities. Methods : Based on a review of the literature, we summarize the concepts of health inequalities and inequities and discuss the underlying assumptions and ethical backgrounds associated with these issues from the view of social justice theory. We then discuss the theoretical and practical implications of health inequalities. Results : Health inequality involves ethical considerations, such as judgments on fairness, and it could provide a sensitive barometer to reflect the fairness of social arrangements. Discussion on health inequalities could deepen our understanding of the social etiology of health and provide a basis for the development of comprehensive and integrative social policies. Conclusions : Health equity is not a social goal in and of itself, but should be considered as a part of a broader effort to seek social justice.

• 반도체디스플레이기술학회지
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• 제2권3호
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• pp.1-6
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• 2003

In the rapid changes of the semiconductor manufacturing technologies for early 21st century, it may be safely said that a kernel of terms is the size increase of Si wafer and the size decrease of semiconductor devices. As the size of Si wafers increases and semiconductor device is miniaturized, the units of cleaning processes increase. A present cleaning technology is based upon RCA cleaning which consumes vast chemicals and ultra pure water (UPW) and is the high temperature process. Therefore, this technology gives rise to environmental issue. To resolve this matter, candidates of advanced cleaning processes have been studied. One of them is to apply the electrolyzed water. In this work, electrolyzed water cleaning was compared with various chemical cleaning, using Si wafer surfaces by changing cleaning temperature and cleaning time, and especially, concentrating upon the contact angle. It was observed that contact angle on surface treated with Electrolyzed water cleaning was $4.4^{\circ}$ without RCA cleaning. Amine series additive of high pKa (negative logarithm of the acidity constant) was used to observe the property changes of cathode water.