• 한국인터넷방송통신학회논문지
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• 제21권6호
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• pp.123-128
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• 2021

직류 배전시스템의 보급이 증가됨에 따라 이에 따른 고장 발생 및 화재 사고도 증가하고 있고 특히 스마트 그리드의 구성 요소인 ESS 화재 사고, 직류 시스템인 태양광 발전 시스템의 화재 사고는 신재생에너지의 보급이 급격하게 증가하고 동시에 사용 연수 10년 이상의 노후 시설이 많아짐에 따라, 시스템 구성 요소 간의 전기적인 접속의 문제들로 발생하고 있다. 이로 인해 유발된 빛과 열을 방출하여 직접적인 화재의 원인이 될 수 있는 아크가 화재의 한 원인으로 지적되고 있다. 따라서 이러한 아크 결함의 문제는 기존의 과전류차단기와 누전차단기로는 아크사고를 사전에 차단할 수 없는 실정이며 대규모 유틸리티 시스템뿐만 아니라 소규모 주거 시스템에서도 인간의 안전에 중대한 위협이 될 수 있기에 아크사고에 대한 대책이 필요하다. 본 논문에서는 국제표준화에 만족하는 시험장비 개발과 아크 발생에 따른 고장 및 화재를 보호하기 위한 직류 아크 Generator를 개발 하고자 한다.

• Advances in aircraft and spacecraft science
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• 제6권2호
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• pp.145-156
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• 2019

As the industrial desire for a step change in productivity within the manufacture of composite structures increases, so does the interest in Through-Thickness Reinforcement technologies. As manufacturers look to increase the production rate, whilst reducing cost, Through-Thickness Reinforcement technologies represent valid methods to reinforce structural joints, as well as providing a potential alternative to mechanical fastening and bolting. The use of tufting promises to resolve the typically low delamination resistance, which is necessary when it comes to creating intersections within complex composite structures. Emerging methods include the use of 3D woven connectors, and orthogonally intersecting fibre packs, with the components secured by the selective insertion of microfasteners in the form of tufts. Intersections of this type are prevalent in aeronautical applications, as a typical connection to be found in aircraft wing structures, and their intersections with the composite skin and other structural elements. The common practice is to create back-to-back composite "L's", or to utilise a machined metallic connector, mechanically fastened to the remainder of the structure. 3D woven connectors and selective Through-Thickness Reinforcement promise to increase the ultimate load that the structure can bear, whilst reducing manufacturing complexity, increasing the load carrying capability and facilitating the automated production of parts of the composite structure. This paper provides an overview of the currently available methods for creating intersections within composite structures and compares them to alternatives involving the use of 3D woven connectors, and the application of selective Through-Thickness Reinforcement for enhanced damage tolerance. The use of tufts is investigated, and their effect on the load carrying ability of the structure is examined. The results of mechanical tests are presented for each of the methods described, and their failure characteristics examined.

• 한국건축시공학회지
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• 제19권5호
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• pp.439-448
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• 2019

아파트 프로젝트는 사업성패에 영향을 미치는 요인은 매우 다양하다. 그러나 분양단가가 결정되고, 분양이 시작된 이후에는 사업에 가장 큰 영향을 미치는 요인은 분양 후 1개월간의 초기분양률이다. 일반적으로 사업주체는 경제상황, 주택시장의 동향, 사업지 인근의 주택가격 등 다양한 자료에 의해 초기분양률을 예측한다. 그러나 이러한 요인들을 초기분양률과 연계하여 정량적으로 계산하는 것은 매우 어렵다. 따라서 본 연구는 실제 수행된 아파트 프로젝트의 분양결과 자료를 이용하여 초기분양률 예측 회귀모델을 제안하는 것을 목적으로 한다. 본 연구를 위해 기존 분양실적자료 수집, 영향요인들의 상관관계 분석, 초기분양률 예측 회귀모델 작성을 진행한다. 본 연구의 결과는 아파트 프로젝트의 사업성 분석 시 초기 분양률 예측을 위한 기초자료로 활용되며, 사업 리스크 모델 개발의 핵심 자료로 활용된다.

• 한국산업융합학회 논문집
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• 제21권6호
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• pp.395-408
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• 2018

Even after the Fukushima nuclear accident in 2011, the rate of production of electric energy using nuclear energy is increasing, but there is a great danger such as the radioactive waste produced when using nuclear power, the catastrophic accident of nuclear power plant, and connection with nuclear weapons. In particular, Cs present in the ionic form of alkaline elements has a long half-life (30.17 years) because it is readily absorbed by the organism and emits intense gamma rays, thus presenting a serious radiation hazard. Therefore, it must be completely removed before it can be released into the natural ecosystem, because it can adversely affect not only humans but also natural ecosystems. Many adsorbents and ion exchangers which have high Cs removal efficiency have been used in recent years to completely separate and remove by self separation in water. Many adsorbents and ion exchangers which have high Cs removal efficiency have been used in recent years to completely separate and remove by self separation in water. In addition, researches have been doing to synthesize magnetic materials with adsorbents such as HCF and PB, and it shows a great effect in the removal rate of Cs present in wastewater or the maximum Cs adsorption amount. In particular, when a magnetic material was applied, excellent results were obtained in which only Cs was selectively removed from other cations. However, new problems such as applicability in the sea where Cs is directly released, applicability in various pH ranges, and failure to preserve the magnetizing force possessed by the magnetic body have been found. However, researches using ferromagnetic field with stronger magnetic properties than those of magnetic bodies is considered to be insufficient. Therefore, it is considered that if the researches combining the ferromagnetic field with the magnetization ability and functional adsorbents more actively, the radioactive material Cs which adversely affects the natural ecosystem can be effectively removed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권1호
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• pp.1-19
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• 2021

The graph-based tag recommendation algorithm FolkRank can effectively utilize the relationships between three entities, namely users, items and tags, and achieve better tag recommendation performance. However, FolkRank does not consider the internal relationships of user-user, item-item and tag-tag. This leads to the failure of FolkRank to effectively map the tagging behavior which contains user neighbors and item neighbors to a tripartite graph. For item-item relationships, we can dig out items that are very similar to the target item, even though the target item may not have a strong connection to these similar items in the user-item-tag graph of FolkRank. Hence this paper proposes an improved FolkRank algorithm named FolkRank++, which fully considers the user-user and item-item internal relationships in tag recommendation by adding the correlation information between users or items. Based on the traditional FolkRank algorithm, an initial weight is also given to target user and target item's neighbors to supply the user-user and item-item relationships. The above work is mainly completed from two aspects: (1) Finding items similar to target item according to the attribute information, and obtaining similar users of the target user according to the history behavior of the user tagging items. (2) Calculating the weighted degree of items and users to evaluate their importance, then assigning initial weights to similar items and users. Experimental results show that this method has better recommendation performance.

• 한국컴퓨터정보학회논문지
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• 제27권3호
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• pp.79-90
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• 2022

'신뢰'란 사람이나 사물에 대해 '믿고 의지하는 것'이면서, 동시에 특정 공동체나 사회의 기반이자 존속의 필수 조건이다. 블록체인 기술이 어떻게 신뢰를 만드는지는, 관련 정보를 참여자 모두가 공유하는 기술이라는 점에서 그 답을 찾을 수 있다. 공유의 기술인 블록체인은 그 기술 자체로 투명성, 불변성, 가용성이라는 세 가지 특징을 가진다. 공유하기 때문에 투명하고, 공유하기 때문에 불변, 곧 수정하거나 삭제하기 어려우며, 공유하기 때문에 일부 장애가 발생해도 전체 시스템은 정상 운영된다. 이 블록체인 기술을 기반으로 만들어지는 신뢰가 가진 의의는 다음과 같이 세 가지 측면에서 정리할 수 있다. 첫째는 신뢰의 문제를 기술과 연결해 이해하는 것, 둘째는 정보와 신뢰의 관계를 이해하고 본격적으로 주목하기 시작한다는 것, 셋째는 확대된 정보처리 능력을 토대로 중앙의 매개 없이 대규모의 구체적인 상호관계를 맺을 수 있게 되었다는 점이다.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제28권2호
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• pp.31-38
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• 2022

Purpose: This study presents the results of the analysis on space utilization of kidney dialysis units in regional public hospitals, which plays a key role in local public medical services. The result aims to achieve safety from infection, allow comfort for the dialysis environment, and stability for medical support. The purpose of this study is to present fundamental data for architectural plans for the kidney dialysis unit, as well as to alleviate potential infectious diseases such as COVID-19. Methods: For research purposes, the investigation and analysis of space utilization were based on architectural floor plans, research papers and literature, related legal systems, and public statistics. Of the main 35 regional public hospitals, in regards to data accessibility, 15 facilities were selected to conduct the survey and analysis for the objective. Results: The space composition by area research results of kidney dialysis units in public hospitals are as follows: Firstly, most targets do not have required rooms in the access and support area, except for the hemodialysis beds in the treatment section. Secondly, the access area requires necessary room and space design that took into consideration of convenience and accessibility for patients. Thirdly, in regards to infection prevention and control, proper circulation and room plan is essential for storage and disposal of contaminated products and linen after use. For the treatment area, the arrangement plan needs to establish a visual connection between the isolation room, the nursing station, and the bed area. Additionally, consideration of circulation in the preparation, treatment, observation, examination, and all other rooms in the facility is required. Lastly, for the support area, the room is designed to consider adequate working and meeting spaces for the medical staff, consultation space for patients or guardians, separate storage and disposal of clean and contaminated items, and the storage of various equipment for dialysis. Implications: In preparation for the increase in chronic kidney failure patients and the spread of infectious diseases, such as COVID-19, the researched data demonstrates the basic guidelines for space composition of kidney dialysis units and the significant role of regional public hospitals.

• 마이크로전자및패키징학회지
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• 제29권2호
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• pp.33-41
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• 2022

최근 플렉시블 전자소자의 안정적인 전기적 연결을 위한 유연전도성 접합 기술의 연구 필요성이 대두되고 있다. 기존의 금속 납땜 접합에서 발생하는 기계적 파손 문제는 탄성 계수가 작거나 두께가 얇은 재료를 기반으로 제작된 유연전도성 접합을 통해 해결할 수 있다. 기계적 특성을 향상시키는 동시에 안정적인 전기적 연결이 가능하도록 높은 전기전도도를 가진 물질을 박막화하거나, 작은 탄성 계수를 가진 물질에 혼합하는 방식 등으로 형성된다. 대표적인 유연전도성 접합 기술로는 박막 증착을 통한 유연전도성 접합, 유연 전도성 접착제 기반 접합, 그리고 액체 금속 기반의 전도성 접합 형성 방법 등이 있으며 본 논문에서는 각 방법들의 기계적/전기적 특성 향상 전략과 그 쓰임을 소개한다.

• 한국전산구조공학회논문집
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• 제36권1호
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• pp.27-38
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• 2023

본 논문에서는 최근 4차 산업혁명을 통해 최신 ICT 기술을 접목하여 대한민국의 항만, 해운, 조선 및 기자재 산업이 물샐틈없는 완벽 공조를 통한 가치 사슬, Seamless Value Chain이 Smart Seamless Value Chain 성공적인 구축을 위한 산업 간의 협력관계를 정의하고, 이들 산업의 지속 가능한 발전을 위한 핵심 요소가 무엇인지를 고찰해 보았다. 이를 통해 오늘날 디지털화를 통한 탈탄소화를 실현하여 ESG 경영 달성을 위한 방향도 제시하였다. 그리고 특히 중소기업의 관점에서 미래시장을 대응하기 위한 방안으로서의 디지털화의 중요성과, 특히 중소 기자재 업체가 실현하는 디지털 화가 산업계 전반에서 어떤 역할을 하는지 중점적으로 고찰하였다. 이를 통해 산업 간의 연계 상태와 가치 사슬이 원활한 관계를 반드시 유지해야할 필요 사유를 동시에 보여준다. 그리고 대한민국의 산업에서 얻은 실패 사례를 통한 교훈으로 발판 삼아 향후 지능형 연결의 전략적 통로를 만드는 초석을 구축하는 방향성도 제시하였다.

• 품질경영학회지
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• 제51권1호
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• pp.131-154
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• 2023

Purpose: The purpose of this paper is to design an integrated informatization system that can manage quality & KPI by integrating management systems in the aerospace and defense industry, and study the effect on KPI when applied to related companies. Methods: The 7 management systems required for integration in the AS&D industry were studied, and an empirical analysis was conducted for H company in South Korea for the application of e-QMS integrated informatization & KPI system based on security environment and open quality. Results: The results of this study were analyzed to have an effect on the improvement of customer satisfaction and the positive improvement of quality failure cost in the aerospace and defense industry. And it was analyzed that it works to continuously comply with ethical management and environmental laws and prevent safety accidents. Conclusion: The greatest significance of this study is that it attempted to build an e-QMS integrated system in the aerospace and defense industry. Considering that the case of integrated management system and integrated operation of KPI in related industries has not been introduced in the existing literature, the results of this study will be shared as a meaningful preceding study in the era of digital quality information. In addition, the fact that the open-quality quality innovation methodology emphasizing measurement(M), tracking(T), and connection(C) was actually applied in an AS&D company and its effectiveness was objectively proven. It is expected that it will be a good paper for follow-up research.