• Title/Summary/Keyword: 작동순서

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Experimental Study on Nozzle Ablation in Liquid Rocket Engine (액체로켓의 노즐 삭마에 대한 실험적 연구)

  • Kim, J.W.;Park, H.H.;Kim, S.K.;Kim, Y.
    • Journal of the Korean Society of Propulsion Engineers
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    • v.4 no.3
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    • pp.38-44
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    • 2000
  • In general liquid rocket nozzles are protected from hot combustion gas by regenerative cooling techniques. But due to the complexity of the cooling system, it causes increase of system cost and frequently source of the system malfunction. Recently, instead of regenerative cooing, ablative material are used to protect combustion chamber wall and nozzle. To determine the nozzle material erosion rate and erosion shape, more than 500 hot fire test were performed by using 100 lb thrust experimental liquid rocket. Test variable were propellant feed sequence, injector, position of igniter and liquid oxygen supply temperature.

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Generation Methodology Using Super In-Context Learning (Super In-Context Learning을 활용한 생성 방법론)

  • Seongtae Hong;Seungjun Lee;Gyeongmin Kim;Heuiseok Lim
    • Annual Conference on Human and Language Technology
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    • 2023.10a
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    • pp.382-387
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    • 2023
  • 현재 GPT-4와 같은 거대한 언어 모델이 기계 번역, 요약 및 대화와 같은 다양한 작업에서 압도적인 성능을 보이고 있다. 그러나 이러한 거대 언어 모델은 학습 및 적용에 상당한 계산 리소스와 도메인 특화 미세 조정이 어려운 등 몇 가지 문제를 가지고 있다. In-Context learning은 데이터셋에서 추출한 컨택스트의 정보만으로 효과적으로 작동할 수 있는 효율성을 제공하여 앞선 문제를 일부 해결했지만, 컨텍스트의 샷 개수와 순서에 민감한 문제가 존재한다. 이러한 도전 과제를 해결하기 위해, 우리는 Super In-Context Learning (SuperICL)을 활용한 새로운 방법론을 제안한다. 기존의 SuperICL은 적용한 플러그인 모델의 출력 정보를 이용하여 문맥을 새로 구성하고 이를 활용하여 거대 언어 모델이 더욱 잘 분류할 수 있도록 한다. Super In-Context Learning for Generation은 다양한 자연어 생성 작업에 효과적으로 최적화하는 방법을 제공한다. 실험을 통해 플러그인 모델을 교체하여 다양한 작업에 적응하는 가능성을 확인하고, 자연어 생성 작업에서 우수한 성능을 보여준다. BLEU 및 ROUGE 메트릭을 포함한 평가 결과에서도 성능 향상을 보여주며, 선호도 평가를 통해 모델의 효과성을 확인했다.

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Conceptual Design of the Fuel Injection Valve Tester for ME-LGI Marine Engine by Using System Engineering (ME-LGI 선박엔진용 연료분사밸브 테스터 개발을 위한 시스템 엔지니어링 기반 개념 설계)

  • Noh, Hyonjeong;Kang, Kwangu;Bae, Jaeil
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.5
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    • pp.681-688
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    • 2018
  • As environmental regulations have been strengthened and high fuel efficiency has been in demand in recent years, the number of ships using natural gas as a fuel is increasing. The demand for ships using LPG or methanol, which are emerging as eco-friendly vessel fuels, is also increasing. In this perspective, ME-LGI engines using LPG or methanol as a fuel have attracted considerable attention. Ships equipped with an ME-LGI engine are required to check the reliability of the fuel injection valve during shipping. This means that the development of a fuel injection valve tester is essential for the commercialization of ME-LGI engine. This study conducted the conceptual design of a fuel injection valve tester for ME-LGI engines using a system engineering process in the order of requirements analysis, functional analysis, and design synthesis. In the requirement analysis stage, the operating process of fuel injection valve was analyzed, and the necessity of checking the sealing oil leakage was then derived. In the functional analysis stage, the functions and flow of them were defined at each functional level. In the design synthesis stage, the equipment for each function was set and the process block diagram based on it was derived. In addition, preliminary risk analysis was performed as a part of system analysis and control, and safety measures were added to the conceptual design. This study is expected to be a good reference material for the concept design of other systems in the future because it shows the application process of a system engineering process to the conceptual design in detail.

A Study on Collaborative Governance: Focusing on the Cultural Heritage Guardians (문화재지킴이 정책의 협력적 거버넌스 운영 체계 연구)

  • Jang, Youngki
    • Korean Journal of Heritage: History & Science
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    • v.54 no.1
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    • pp.184-205
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    • 2021
  • Governance is valued as a new concept and principle of social operation and public policy management, and its influence is gradually expanding. Among the various governance theories being put into practice and in case analysis studies, collaborative governance embracing various governance concepts has been found to increase interdependence and responsibility beyond participation and compromise, and create new public values by integrating and utilizing optimal social coordination forms. In the field of cultural assets, governance-related research is also being conducted for the efficiency, sustainability, and scalability of public policy enforcement. This study explored the government's role (promotion, arbitration, and condition creation) in collaborative governance, focusing on the "Cultural Heritage Guardians" to understand how collaborative governance operates in the cultural heritage sector. Regarding governance policies in the cultural asset sector, the cultural asset guardians highlighted the status, role, and characteristics of policies by examining their introduction, development, and implementation. The results of the analysis revealed that private-led, horizontal public-private cooperation, collaborative governance, policy introduction, solidarity, professionalism, resource/knowledge imbalance, cooperation precedence, etc., facilitate increased participation. The government has accordingly proposed measures to establish comprehensive legal stability centered on cooperation; strategic reorganization of dedicated organizations; strengthened, supportive intermediate organizations; and individual and multi-party consultative bodies.

Efficiency Evaluation of Genetic Algorithm Considering Building Block Hypothesis for Water Pipe Optimal Design Problems (상수관로 최적설계 문제에 있어 빌딩블록가설을 고려한 유전 알고리즘의 효율성 평가)

  • Lim, Seung Hyun;Lee, Chan Wook;Hong, Sung Jin;Yoo, Do Guen
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.5
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    • pp.294-302
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    • 2020
  • In a genetic algorithm, computer simulations are performed based on the natural evolution process of life, such as selection, crossover, and mutation. The genetic algorithm searches the approximate optimal solution by the parallel arrangement of Schema, which has a short definition length, low order, and high adaptability. This study examined the possibility of improving the efficiency of the optimal solution by considering the characteristics of the building block hypothesis, which are one of the key operating principles of a genetic algorithm. This study evaluated the efficiency of the optimization results according to the gene sequence for the implementation in solving problems. The optimal design problem of the water pipe was selected, and the genetic arrangement order reflected the engineering specificity by dividing into the existing, the network topology-based, and the flowrate-based arrangement. The optimization results with a flowrate-based arrangement were, on average, approximately 2-3% better than the other batches. This means that to increase the efficiency of the actual engineering optimization problem, a methodology that utilizes clear prior knowledge (such as hydraulic properties) to prevent such excellent solution characteristics from disappearing is essential. The proposed method will be considered as a tool to improve the efficiency of large-scale water supply network optimization in the future.

Efficient Security Mechanism using Light-weight Data Origin Authentication in Sensor Networks (경량화 데이터 origin 인증을 통한 효율적인 센서 네트워크 보안에 관한 연구)

  • Park, Min-Ho;Lee, Chung-Keun;Son, Ju-Hyung;Seo, Seung-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.7A
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    • pp.717-723
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    • 2007
  • There are many weaknesses in sensor networks due to hardware limitation of sensor nodes besides the vulnerabilities of a wireless channel. In order to provide sensor networks with security, we should find out the approaches different from ones in existing wireless networks; the security mechanism in sensor network should be light-weighted and not degrade network performance. Sowe proposed a novel data origin authentication satisfying both of being light-weighted and maintaining network performance by using Unique Random Sequence Code. This scheme uses a challenge-response authentication consisting of a query code and a response code. In this paper, we show how to make a Unique Random Sequence Code and how to use it for data origin authentication.

A Study on a Elevator Emergency Call Device System and Performance Evaluation based on ICT for Efficient Handling in Emergency Situation (위급상황 시 효율적인 대처를 위한 ICT 기반의 엘리베이터 비상통화장치 시스템 및 성능 비교 연구)

  • Jung, Se-Hoon;Park, Sung-Kyun;Park, Hong-Jun;So, Won-Ho;Park, Dong-Kook;Sim, Chun-Bo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.10 no.4
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    • pp.449-459
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    • 2015
  • A lot of people were trapped in elevators without power supply when BLACK-OUT situation occurred in 2011. The telephone network of control room connected to the elevators had problem operating poorly. In this paper we propose an ICT based elevator emergency call device prototype system and evaluate the performance of the system. The proposed system quickly responds in emergency situation to guarantee passenger safety. For the goal, firstly the system tries to connect to a control room. If it fails the system attempts to call numbers for emergency contact and a rescue team sequentially. The system is designed to quickly support emergency contact as well. Finally, the information of elevator failure is rapidly transferred to the failure process device by the proposed system.

Comparative Analysis Study between Korean public education and Waldorf education Focusing on Teaching the Numbers from 0 to 10 (우리나라 공교육과 발도르프 교육에서 0부터 10까지의 수 지도 비교 연구)

  • Cho, Youngmi
    • School Mathematics
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    • v.15 no.1
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    • pp.137-158
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    • 2013
  • In this paper we compared waldorf education with korean public education in the area of teaching the numbers form 0 to 10. We took several characters of both. The korean education style has the characters like separation of 0~9 and 10, teaching of the meaning of ordinal numbers and cardinal numbers, use of storytelling. The waldorf education style has the characters like teaching of the qualitive meaning of numbers, use of storytelling, meeting numners in rhythm, teaching from whole to part.

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Efficient Security Mechanism using Light-weight Data Origin Authentication in Sensor Networks (경량화 데이터 Origin 인증을 통한 효율적인 센서 네트워크 보안에 관한 연구)

  • Park, Min-Ho;Lee, Chung-Keun;Son, Ju-Hyung;Seo, Seung-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.5A
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    • pp.402-408
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    • 2007
  • There are many weaknesses in sensor networks due to hardware limitation of sensor nodes besides the vulnerabilities of a wireless channel. In order to provide sensor networks with security, we should find out the approaches different from ones in existing wireless networks; the security mechanism in sensor network should be light-weighted and not degrade network performance. Sowe proposed a novel data origin authentication satisfying both of being light-weighted and maintaining network performance by using Unique Random Sequence Code. This scheme uses a challenge-response authentication consisting of a query code and a response code. In this paper, we show how to make a Unique Random Sequence Code and how to use it for data origin authentication.

A Study of Programming Language Class with Lego NXT Robot for University of Education Students - Centered on Maze Problem - (레고 NXT 로봇을 활용한 예비교사의 프로그래밍 언어 수업 방안 - 미로 찾기 문제를 중심으로 -)

  • Hong, Ki-Cheon
    • Journal of The Korean Association of Information Education
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    • v.13 no.1
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    • pp.69-76
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    • 2009
  • This paper proposes a teaching plan of programming language class for university of education students amusingly with LEGO Mindstorms NXT robot. The goal of class is not fragmentary knowledge acquirement but problem-solving of maze. This robot communicates with GUI named NXT-G installed in computer via USB. GUI is not text-based but icon-based programming tool. This paper designs a semester with 3 steps such as beginner, intermediate, high-rank. Beginner step is consists of learning of basic functions such as GUI usage and several sensors of robot. Intermediate step is consists of solving of maze problem with low complexity. High-rank step is consists of solving maze problem with medium and high complexity. All maze problem-solving have 3 process with algorithm, flowchart, and programming with stack.

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