• Wind and Structures
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• 제32권5호
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• pp.501-508
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• 2021

The turbine industry demands a reliable design with affordable cost. As technological advances begin to support turbines of huge sizes, and the increasing importance of wind turbines from day to day make design safety conditions more important. Wind turbines are exposed to environmental conditions that can affect their installation, durability, and operation. International Electrotechnical Commission (IEC) 61400-1 design load cases consist of analyses involving wind turbine operating conditions. This design load cases (DLC) is important for determining fatigue loads (i.e., forces and moments) that occur as a result of expected conditions throughout the life of the machine. With the help of FAST (Fatigue, Aerodynamics, Structures, and Turbulence), an open source software, the NREL 5MW land base wind turbine model was used. IEC 61400-1 wind turbine design standard procedures assessed turbine behavior and fatigue damage to the tower base of dynamic loads in different design conditions. Real characteristic wind speed distribution and multi-directional effect specific to the site were taken into consideration. The effect of these conditions on the economic service life of the turbine has been studied.

• International Journal of Advanced Culture Technology
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• 제10권3호
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• pp.397-403
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• 2022

The world is paying a lot of attention to digital twins to preoccupy future technological competitiveness. Digital twins can be used in various fields such as manufacturing, medical care, and cities. Various market research institutes predict that the market size of digital twins will gradually expand. Korea has also selected digital twin as one of the representative tasks of the Korean version of the New Deal and is promoting related policies. However, a common platform or standard for building digital twins is not enough. Interoperability is a very important characteristic for the purpose of creating new value through interconnection between digital twins rather than independently developing and utilizing digital twins. The Digital Twin Consortium is an international council for the effective development and utilization of digital twins, and is working to solve the problem of digital twin interoperability. The Digital Twin Consortium recently published the 'Digital Twin System Interoperability Framework', and this paper analyzes the digital twin interoperability based on it.

• 기술혁신연구
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• 제15권2호
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• pp.123-152
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• 2007

The striking characteristic of the contemporary global security environment is that the nature of threats has become diverse and complex. For example, transnational and non-military threats including terrorism and proliferation of weapon of mass destruction has increased. In this security environment, Advanced countries funnel their investments for defense budgets into the assurance of key force capability and R&D of cutting-edge core technologies, in consideration of future battlefield environments so as to get an edge on not only defense science and technology but also intelligence capabilities. As shown by past practices of the korea's defense acquisition, the ministry of national defense has tried to enhance its force capabilities in the short-term by purchasing foreign weapon systems rather than by investing in domestic R&D. Accordingly, the technological gaps between the korea and advanced countries were widened due to both insufficient investment in development of domestic technologies and avoidance of technological transfer by advanced countries. Thus, for the effective execution of the R&D budget and the successful performance of the projects, the importance of selection, management and evaluation of the R&D projects is emphasized. So, The objective of this study is that the analysis of the proposal-selection evaluation system for the realization of the successful defense core technology R&D projects. This study focused on the improvement of the proposal-selection evaluation model which can be applicable to the national defense core R&D projects. Using the improved proposal-selection evaluation system, we propose a model to enhance the reliability of the national defense core technology R&D project evaluation system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.349-353
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• 2001

Korea has a variety of favorable conditions for utilizing wind as energy. First of all, as a geographical characteristic, it is a peninsular country with its three frontiers surrounded by sea. Such a location makes the country influenced, all the year round, both by sea winds and by seasonal winds, so that it has a good possibility of putting its rich wind resources to use as an energy source. Particularly, in view of the results of observations and analysis of actual data about wind sources, it is quite possible to build wind paver plants in many regions across the country, such as inhabited islands dotted on its southern and western coasts around the Korean peninsular, a number of uninhabited islets attached the main islands, large-scaled reclaimed lands, and major inland areas. In Korea, the attempt to develop the technology of wind paver generation started in the 1970's. It was since 1988, when the Law on the promotion of Alternative Energy Development was enacted, that research and development activities for employing the wind force as a part of energy source have got into full swing. At that moment, however, due to the low level of domestic technological development, such efforts were mainly focused on the attainment of basic technologies with regard to wind power generation. Recently, there have been many noticeable changes in the international as well as domestic environments, such as the conclusion of the International Climate Treaty and the increase in public concerns of natural environment. It is quite possible to predict that the demand for wind paver generation will increase in the near future. Therefore, recognizing that wind, as a clean energy source, can be a promising method for coping with the International Climate Treaty and for replacing the fossil fuel, oil, this essay investigates the development history of wind paver generation systems and the status of technological development in Korea and presents an appropriate model for the development of the paver generation system that can compete with other energy sources.

• Journal of Information Processing Systems
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• 제13권4호
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• pp.778-804
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• 2017

Software today has become an inseparable part of our life. In order to achieve the ever demanding needs of customers, it has to rapidly evolve and include a number of changes. In this paper, our aim is to study the relationship of object oriented metrics with change proneness attribute of a class. Prediction models based on this study can help us in identifying change prone classes of a software. We can then focus our efforts on these change prone classes during testing to yield a better quality software. Previously, researchers have used statistical methods for predicting change prone classes. But machine learning methods are rarely used for identification of change prone classes. In our study, we evaluate and compare the performances of ten machine learning methods with the statistical method. This evaluation is based on two open source software systems developed in Java language. We also validated the developed prediction models using other software data set in the same domain (3D modelling). The performance of the predicted models was evaluated using receiver operating characteristic analysis. The results indicate that the machine learning methods are at par with the statistical method for prediction of change prone classes. Another analysis showed that the models constructed for a software can also be used to predict change prone nature of classes of another software in the same domain. This study would help developers in performing effective regression testing at low cost and effort. It will also help the developers to design an effective model that results in less change prone classes, hence better maintenance.

• 한국언론정보학보
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• 제16권
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• pp.207-254
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• 2001

This study is focused on forecasting the future of tole-democracy. Many Scholars expect that internet provides technological space needing realizing the tole-democracy or deliberate democracy. Especially in Korea, this expectation is higher than other nations because of political corruption and inefficiency. Therefore internet is intended to considering as new technologies reforming political process. In 16th the general election period, many candidates established home page and used as election campaign tool. And a little of home pages is payed attention to among voters. In spite of using internet as political medium, many political communication researchers have a doubt that internet will realize ideal direct democracy. It's reason is that internet is open and anonymous space. At anonymous space, communication participators is tended to be irresponsible and non-serious. Therefore it is hard that cyber-politics will be ideal type of democracy. In this context, this paper analyzed how pauicipators communicate with others at cyber bulletin board establishing candidate's home pages. Main research questions is how do discussions at cyberspace fulfill the conditions of deliberate democracy. Therefore, concrete questions include; who are participators at candidate's cyber bulletin board; which pattern do they communicate; what is the theme of communication; which effects do the anonymous character of cyberspace influence. To that purpose, this study conducted content analysis on 4,210 written matters at 82 cyber bulletin boards of candidate's home page establishing during 16th the general election period. It can be found that cyberspace in Korea still is not deliberate democracy space and not will be. Firstly, discussion patterns at cyber bulletin board is "candidate with supporters communication space. To be exact, it is said that candidate's home page is "the space of self-convincing among supporters." Secondly, the main themes of discussion are simple emotional expressions; "I support you!" "fighting" "Be vigor" etc. By contrast, real political contents'-central or local political matters - is relatively few. In the mode of expression, real political messages are more positive, logical than simple expressions, candidates private matters. Especially this characteristic will make cyberspace as "mutual slander space" consolidating anonymous characteristic of cyberspace. finally, Cyberspace in Korea still is not real "public sphere" realizing deliberate process. Therefore to be real public sphere, it is needed to participant's ethical maturity and political citizenship. In conclusion, it is difficult that cyberspace will reconstruct the Athene's Agora. On the contrary, Cyberagora will like to be irrespectable area fulfilling the sweeping. Making the deliberate space, technological possibility and ethical condition will have to be balanced together.

• 한국실내디자인학회논문집
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• 제24권5호
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• pp.108-116
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• 2015

This study intends to research the spatial characteristics of Asian interim housing that accommodates sufferers pro tempore after disasters. The scope of this research covers the interim spaces used for housing people after natural disasters that occurred in Asia for the past fifteen years. Within this scope, literature review was conducted as the basis to derive the characteristics and environmental elements of interim housing, which provided the criteria to compare and evaluate cases of interim housing along with characteristic elements required of interim housing found in previous studies. According to literature review, interim housing can be classified by life-span, region, economy, climate, type, number of household, square measure, residential cost, structure/material, and service life. Within the scope of the present research, literature review showed a total of twenty-eight cases of interim housing in fifteen countries revealing a high rate of disaster occurrence in the subtropic and tropic climate of Southeast Asia. A great percentage of interim housing was used for long-term stay of over a year. The structure of interim housing varied from lightweight steel, wooden, masonry, membrane, to traditional structure and the type were divided into temporary shelter, transitional housing, temporary housing, and permanent housing. Followed by literature review, the characteristics required of post-disaster interim housing were analyzed based on previous research and case studies. The characteristics of interim housing can be divided into environmental, technological, and socio-cultural ones. Sub-characterical items according to such division include amenity, health, surroundings, structure, convenience, eco-friendliness, safety, communication, and locality. As a result of evaluation, most items met the required characteristics of interim housing, while technological characteristics such as structure and convenience varied with the types of interim housing and appeared even unnecessary in some cases. According to analysis, amenity is maintained through the structural and material characteristics of interim housing and is also facilitated by increasing number of infrastructure such as educational, sanitary, and convenience facilities provided by the governmental and organizational bodies. It is expected that this study will be utilized as preliminary data for follow-up studies that improve the environment of post-disaster interim housing suitable for domestic circumstances in environmental, technological, and socio-cultural respects.

• 한국미생물·생명공학회지
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• 제49권2호
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• pp.255-263
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• 2021

γ-Aminobutyric acid 생성에 관여하는 glutamate decarboxylase 유전자 gadA/B를 보유한 메주 유래 Enterococcus faecium 88균주를 대상으로 기능적 특성 및 안전성 평가를 진행하여 메주 유래 E. faecium의 발효식품용 종균으로써의 활용 가능성을 검토하였다. 6% NaCl 농도(w/v)에서 모든 균주의 생장 및 산 생성이 확인되었다. 7% NaCl 농도에서는 21균주(24%)가 낮은 생장을 나타냈으며, 72균주(82%)가 약한 산 생성 활성을 나타냈고, 16균주(18%)는 산생성을 나타내지 않았다. 4% NaCl 농도에서는 모든 균주가 단백질 분해 활성을 나타냈지만, 5% NaCl 농도에서 86균주(98%)가 약한 활성을 나타냈고, 1균주(1%)는 활성을 나타내지 않았다. 지방 분해 활성은 모든 균주에서 나타나지 않았다. 모든 균주가 7종의 항생제(ampicillin, chloramphenicol, ciprofloxacin, gentamicin, penicillin G, tetracycline, vancomycin)에 대해 획득형 항생제 내성을 나타내지 않았다. Enterococcus 심내막염 항원 유전자 efaA 및 tyramine 생성에 관여하는 tyrosine decarboxylase 유전자 tdc가 메주 유래 88균주에서 발견되었지만, 사람 기원 E. faecium 균주가 특이적으로 보유하고 있는 Enterococcus surface protein 유전자 esp는 발견되지 않았다.

• 응용통계연구
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• 제23권6호
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• pp.1035-1045
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• 2010

기업이 제공하는 제품 서비스는 시장에 소개되기 전에 기술적 검증과 사용 환경에 대한 객관적인 검토를 거쳐야 한다. 이를 위해 각 기업에서는 경험적으로 확인된 다양한 절차와 방법을 이용하여 올바른 상품력(Power of Product Service)을 판단할 수 있는 객관적인 방법을 연구하고 있다. 상품력은 특정 기능 또는 개별 특성에 대한 평가 보다는 다양한 고객의 요구 사항에 기초한 여러 특성이나 기능들을 동시에 반영할 수 있을 때 바람직하다고 할 수 있다. 고승곤 (2008)은 품질 평가 방법인 시그마 수준(Sigma Level)을 확장하여 다양한 특성들을 종합적으로 반영할 수 있는 MSL(Multi-characteristic Sigma level)을 소개하였다. 본 논문에서는 MSL과 새로운 고객 선호 일치도를 반영하는 BOI(Blue Ocean Index)를 이용한 이동 통신 단말기의 상품력 평가 방법을 확인해 보고 이를 통해 실무적 그리고 통계적으로 고려해야 할 사항들을 검토해 보고자 한다.

• 기술혁신연구
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• 제25권4호
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• pp.211-238
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• 2017

본 연구는 혁신주체 간 협력이 기술혁신 성과에 미치는 영향을 알아보기 위해 사회네트워크분석 및 분산분석 그리고 회귀분석을 실시하였다. 2009년부터 2012년까지 한국 특허청의 공동 출원인 자료를 토대로 네트워크 구조 변수 및 특성 변수를 도출하였다. 이를 통해 전체 네트워크의 구조적 유형, 혁신주체 별 역할 그리고 혁신 성과에 영향을 미치는 네트워크 특성 변수가 무엇인지를 실증 분석하였다. 분석결과를 요약하면 다음과 같다. 첫째, 특허 공동출원인 네트워크는 비교적 소규모 그룹들이 산재해 있는 분산집중형 좁은세상 네트워크 구조이며 혁신주체들이 비교적 느슨하게 연결되어 있었다. 둘째, 특허 공동출원인 네트워크에서 가장 중심적인 역할을 하는 것은 대학교로 밝혀졌으나 협력 파트너의 다양성은 모든 혁신주체가 비슷하였다. 셋째, 익숙한 몇몇 협력 파트너로부터 얻는 신속하고 정확성이 높은 지식이 다양한 분야의 협력 파트너로부터 얻는 생소한 지식보다 성과를 창출하는 데에 보다 긍정적이었다.