• 한국산학기술학회논문지
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• 제14권5호
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• pp.2075-2080
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• 2013

본 논문에서는 RE엔진에 적용하기 위한 냉각수 코어를 CFD 기술을 활용하여 개발하였다. 개선 모델은 배기밸브 주위와 사이의 온도를 저감하기 위한 냉각수 우회부를 추가하였다. 2번 실린더 블록 주위와 배기밸브 사이의 유량이 증가하였기 때문에, 베이스 모델대비 개선 모델의 유량 정체가 개선되었다. 결과적으로, 배기밸브 주위에서의 열전달이 향상되고, 전 유량 구간에서 기존 모델 대비 약 5%의 압력 강하량 저감 효과를 보이는 개선 모델을 얻을 수 있었다. 압력 강하량의 저감은 상응하는 냉각수 펌프의 부하를 저감하고 연비에 긍정적 영향을 미칠 것으로 판단된다.

• 한국정보통신학회논문지
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• 제13권4호
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• pp.821-827
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• 2009

웹 2.0의 발전과 함께 같이 참여와 공유를 통한 지식 기반 시스템은 오늘날 그 중요성이 더해지고 있다. 본 논문에서는 여러 대중을 상대로 이루어진 세미나 내용을 데이터베이스를 통하여 체계적으로 관리하고 이를 지식 공유시스템으로 발전시키는 세미나 보조 시스템에 관한 연구와 구현 결과를 다룬다. 이를 위하여 세미나 데이터베이스에 세미나 음성과 프레젠테이션 파일로 녹화된 내용을 저장하고, 추후에 세미나 수강자가 리뷰시스템을 통하여 수강할 수 있도록 제작하였다. 시스템을 위한 데이터 베이스는 마이크로소프트사의 MS SQL, 서버 측 네트워크를 위한 소켓은 소켓 모델 중에서 확장성이 뛰어난 IOCP 모델을 사용하였다. 강연자가 강연을 위하여 녹화하게 될 프리젠터 소프트웨어는 DirectShow와 WPF(Windows Presentation Foundation) 라이브러리를 사용하였으며, 사용자가 이용하는 리뷰시스템은 WPF와 C# 언어를 사용하여 개발하였다.

• 한국정보처리학회논문지
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• 제3권7호
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• pp.1845-1857
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• 1996

ATM 경보 취합 장치는 $1,024\times1,024$의 대용량 ATM 교환기의 하드웨어 고장 취합 기능을 지원하기 위한 목적으로 8비트 소형 마이크로프로세서 및 EA-232C 통신 방법을 이용하여 AGLA(Alarm Gathering Interface board Assembly)로 부르는 단일 보드로 개발되었고, ATM 교환기를 구성하는 가가 서브시스템 하드웨어 블럭 및 모듈에 대해 온라인 시험을 통하여 성능이 입증되었다. 본 논문은 ATM 교환기의 하드웨어 장에 경보 신호의 관리를 위한 경보 취합 장치의 설계 및 개발에 관하여 기술하였으며 이는 추후 성능이 더욱 우수한 대용량 ATM 교환기의 유지 및 운용 기능을 개발하는데 이용될 수 있다. 아울러 ATM 교환기 경보 취합 비에 대한 향후 연구 항목을 제시하였다.

• 한국항해학회지
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• 제21권4호
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• pp.93-102
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• 1997

History will be defined as a science on human beings in both space and time(des hommes dans le temps et l'espace). Navigational History is a premise to compose Maritime History. Maritime History is a branch of General History which is classified on the basis of space and will be definded as a branch of history to examine 'inter-realtions between maritime affairs and inland affairs'. Then, what kind of 'go by sea'can be a subject of Navigational History ? A research-subject of Navigational History must be navigation rather than sail or voyage. Because while 'sail' means to 'passive and noncommercial sailing' and voyage means to journeyin a general sense that includes sail and navigation, navigation means to indicate ' to go from one place to another in a ship' adn 'to convoy goods by water'. Then, how can we define Navigation History? Navigational History in a narrow sense is to be a field of studying 'process of development of nautical science and seamanship on the side of History ofScience and Techique, whereas Navigational History in a broad sense is to be a field of analyzing 'effects of historical navigation upon history on the side of General History. On studying Navigational History in a narrow sense, there are signifiacances of disclosing what the development of nautical instruments and arts of navigation have played a role in history. Navigational History in a broad sense is a branch of General History to study effects of historical navigation upon history. In conclusion, the significance of studying Navigation History is to disclose process of developmentof arts of navigation, and on the basis of this study is to reveal how the human elements operate in historical navigation. In short, it should not cease to study Navigational History in a narrow sense, and should enlarge its perspective of research toward Navigational History in a broad sense.

• 농촌계획
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• 제16권4호
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• pp.147-156
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• 2010

Among the towns of GyeongJu and SamCheok on which I have surveyed about their amenity resources in 2010, I chose 5 towns that are close to the Eastsea to analyze the data and to devise how to revitalize fishing villages. And the results are as follows. 1. Although Yangbuk-myeon is geographically located to have all the aspects of fishing village, farming village, and mountain village, the resources utilized are mainly that of mountain village. There is need to utilize actively historical amenity resources like Munmudaewangreung of Yangbuk-myeon. 2. The use of amenity resources of Yangnam-myeon is centered on farm and mountain village. But if they utilize amenity resources of fishing villages of Eupcheon-port's neighborhood, it would be a big help for the revitalization of Yangnam-myeon which is depressed. 3. The fishing mackerels on boat of Gampo-eup Jeonchonri is a successful example of utilization of fishing village's amenity resources. However, there is need to utilize amenity resources of farming and mountain villages that are near to Gampo-eup, so it can attract visitors to stay longer. Particularly, the fishing villages of the East coast must develop 4 seasons program connecting the amenity resources of neighboring farm and mountain. 4. Geundeok-myeon is a town where they made the amenity resources of fishing village into tourist attractions. But considering the wide gap between Geundeok-myeon and neighboring fishing, farming and mountain villages that cannot get the advantage of development, there has to be some inducement in policy so every town can be developed evenly. 5. After analyzing how the towns utilize the amenity resources to make them tourist attraction, it is shown that Geundeok-myeon of SamCheok is the best town which is using fishing village's amenity resources well, and Yangnam-myeon and Yangbuk-myeon of GyeongJu are scarcely using them. About types of tourist attraction, the programs with scenic view of fishing village, with water-sport, and with Eco-experience are needed to improved.

• 한국농촌건축학회논문집
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• 제21권4호
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• pp.45-52
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• 2019

Chemical grouting method is mainly used for construction of dams and reservoirs, stabilization and reinforcement of slopes, reinforcement of soft grounds such as embankments, dredging and landfills, the order of earthquake response method, and the reinforcement of structures. Recently, it is widely applied in construction sites such as highways, airfields, high-speed railways, subsea facilities, port construction works, tunnels, and subway works. As such, the demand for grouting continues to increase. The development of the grouting method was focused on increasing the strength of the ground, and the development of the chemical additives, the injection device, and the stirring device were mainly performed. But ordinary portland cement used for grouting is a product that consumes natural resources such as limestone, generates a large amount of greenhouse gases, consumes a large amount of energy sources, and it is time to develop products and new methods to replace them. In this study, Ordinary Portland Cement and New Grouting Binder (circulating fluidized bed boiler fly and blast furnace slag) were compared and analyzed by the following test. Homo-gel strength and homo-gel time, water quality analysis of the water used and soil contamination process tests of homo-gel samples were performed. In the case of NGB, when Using water is used as the reservoir water, the strength measured smaller than that of the other water. However, it shows about 2.5 times greater than the homo-gel compressive strength applied to OPC (7-day, reservoir water), so there is no problem with water quality when applied.

• International Journal of Knowledge Content Development & Technology
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• 제9권4호
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• pp.7-29
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• 2019

The study was carried out to investigate the influence of demographics and social media use on perceived academic stress of secondary school students in St. Thomas Aquinas College, Akure, Nigeria. This was achieved using five research questions and four null hypotheses. The population of the study consisted of 1,107 students at ISCED level 3, out of which 286 were selected based on the Israel (2003) model for determining sample size. The Ex-Post Facto (EPT) research design of the correlational type was employed to investigate the study while questionnaire was used for data elicitation. Out of the 286 copies distributed, 192 (67% response rate) were retrieved and analyzed using descriptive statistics (frequency, percentage, mean and standard deviation) and inferential statistics (correlation and multiple regression). The findings revealed that there is high frequency of social media use among secondary school students, majorly for meeting new friends and chatting. The perceived academic stress (PAS) of the students was found to be moderate. Of the three demographics considered, only class had significant influence on PAS. Use of social media did not have significantly influence on PAS of the students. When combined, demographics and social media use predicted PAS; and when considered relatively, of the independent variables, only class as an aspect of demographics predicted PAS. Therefore, the authors concluded that PAS of secondary school students is not directly influenced by demographics (except for class) and social media use. Based on the study's conclusion, recommendations were made.

• 한국해양공학회지
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• 제33권3호
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• pp.300-311
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• 2019

An ROV trencher is a type of heavy-duty work class ROV equipped with high-pressure water jet tools for cutting into the sea floor and burying cables. This kind of trencher is mostly used for PLIB operations. This paper introduces the development of this kind of ROV trencher, which has a 698 kW power system, with a 250 kW hydraulic system and two 224 kW water jet systems. The project was launched in January 2014. After four years of design, manufacturing, and system integration, we carried out two sea trials near the Yeongilman port (about 20-30 m in depth) in Pohang to evaluate the system performance in November 2017 and August 2018. Through tests, we found that most of specifications were satisfied, including a maximum bury depth of 3 m, maximum bury speed of 2 km/h, and maximum forward speed of 1.54 m/s.

• 디지털융복합연구
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• 제15권2호
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• pp.233-238
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• 2017

최근 해양관광의 행태는 다양해지고 있지만 해안지역의 개발은 시설의 확충, 천연자원의 개발, 관광자원 개발 등 융복합적 산업의 개발이라는 어려움으로 정책 추진의 어려움을 겪고 있다. 본 연구는 관광객과 어촌어항이 함께 할 수 있는 융복합적인 측면에서 정책의 접근이 필요하다는 연구의 목적을 가지고 접근하였다. 본 연구에서는 해양관광산업과 관련된 정책을 조사하였으며, 해안지역과 어촌어항 지역 개발과 관련된 법령들을 조사하였다. 그리고 이를 바탕으로 융복합적 정책의 접근을 위한 문제점과 개발방안을 제시하였다. 해양관광 정책의 융복합적 접근 방안으로는 첫째, 해양관광자원 개발은 자연 보호 보전을 우선으로 하는 관광자원이 개발이 되어야 한다. 둘째, 지역 주민의 삶을 우선으로 하고 같이 참여할 수 있도록 법령의 개선과 지역 조례 등을 활용한 관리가 필요하다. 특히 '어촌 체험 마을' 등 현재 진행되고 있는 지원 사업 등을 통한 성공적인 모델을 발굴해야 한다.

• 한국해안·해양공학회논문집
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• 제32권1호
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• pp.11-16
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• 2020

인터로킹 케이슨에 의한 장대화된 방파제의 회전 안정성에 대해서 연구하였다. 무한 방파제에 경사지게 입사하는 선형파에 대한 해석해를 이용하여 방파제 기준선 방향으로의 파압 위상차 효과를 고려하였으며, 설계파의 비선형 특성을 고려하기 위하여 설계 기준 Goda 파압식을 차용하였다. 방파제의 회전 안전율을 케이슨 자중에 의한 회전 마찰저항모멘트와 수평 및 수직 파력에 의한 작용 회전모멘트의 비로 정의하고 최소 안전율을 보이는 회전 중심점 위치와 최소 안전율에 대한 해석해를 제시하였다. 규칙파, 불규칙파 및 다방향 불규칙파 등 현행 항만구조물 설계에 사용되고 있는 모든 설계파 조건에 대해서 적용 가능하도록 각 조건에 대한 평가식을 제안하였다.