• 제목/요약/키워드: Grad

검색결과 425건 처리시간 0.031초

Langumir-Blodgett법으로 제작된 polyimide 超薄膜(초박막)의 전기적특성(電氣的特性) (A study on the Electric Characteristics of Polyimide Ultra Thin through LB-Method)

  • 박상현;윤성도;정학수;국상훈
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1992년도 추계학술대회 논문집
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    • pp.63-66
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    • 1992
  • Using an aromatic system, we made a ultra thin insulator through LB-method. We measured and wrote down afternating currant characteristics of ultraviolet rays extincting-spectrum and I.R extincting-spectrum. We surveyed the thickness of a film through X-ray diffracting method and certified about $4{\AA}$ by the layer. Measuring the characteristics of direct current voltage and electric current with this sample, we produced its conductivity and discovered that this sample had a god insulating performance. Addition to this, we measured the characteristics of voltage and electric current, and the temperature dependency of conductivity in a high voltage system and with these results tried to interpret a mechanism of conduction.

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다수 캐비티 금형에서 엘라스토머 수지의 균형충전도 연구 (A Study on the Filling Balance of Elastomer TPVs in Multi-Cavity Injection Mold)

  • 노병수;한성렬;한동엽;정영득
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2006년도 춘계학술대회 논문집
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    • pp.407-408
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    • 2006
  • Almost all injection molds have multi-cavity, which are designed with geometrically balanced runner system in order to made filling balance between cavity to cavity during injection molding. However, filling imbalance has been existed in the geometrically balanced runner system. In this study, we made an experiment and surveyed that are filling balanced variation according to molding condition with thermoplastic vulcanizate (TPV). Also, we conducted experiments in order to know the influence of filling balance for runner core pin (RC pin).

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수소기관의 수소연료의 희석에 의한 역화억제효과에 관한 연구 (A Study on Enhancement of Combustion Performance by Dilution of Hydrogen in Heavy-Duty Hydrogen Engine)

  • 김서영;김윤영;김용태;이종태
    • 한국수소및신에너지학회논문집
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    • 제15권4호
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    • pp.348-354
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    • 2004
  • Hydrogen gas has several merits such as lower ignition energy, wide flammability and shorter quenching distance. It leads to high thermal efficiency but backfire occurrence. In this study, feasibility of expansion of BFL(Back-Fire Limit) equivalence ratio and combustion characteristics by a dilution of hydrogen fuel are experimently examined by using experimental heavy duty single cylinder hydrogen fueled engine. As results, it is found that BFL equivalence ratio is expanded to rich range and torque is increased.

Efficient Model Checking of Asynchronous Systems Exploiting Temporal Order-Based Reduction Method

  • Yamada, Chikatoshi;Nagata, Yasunori;Nakao, Zensho
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -3
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    • pp.1964-1967
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    • 2002
  • Recently design verification have been played an important role in the design of large scale and complex systems. In this article, we especially focus on model checking methods. Behaviors of modeled systems are generally specified by temporal formulas of computation tree logic. However. Users must know well temporal specification because the specification might be complex. We proposed method that temporal formulas are gained inductively and amounts of memory and time are reduced. Finally, we will show verification results using our proposed method.

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요구관리산출물과 위험관리산출물의 연계 방안 (The Mapping Method between Requirement Tracebility Table and Risk Management List)

  • 한소연;김주영;류성열
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2007년도 가을 학술발표논문집 Vol.34 No.2 (B)
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    • pp.108-113
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    • 2007
  • 소프트웨어 개발 프로젝트의 위험관리는 프로젝트의 성패를 좌우하는 매우 중요한 영역이다. 그러나 위험관리의 주체가 관리자의 역할을 가진 사람들에 의해 진행되고, 방법론이나 지침에서 제시하고 있는 위험관리 또한 여러 활동들과 산출물이 실제 위험관리정보를 필요로 하는 개발자들에게는 적절하게 연결이 되지 않고 있어서 개발자들이 필요한 정보를 파악하기에 문제점이 있다. 이에 따라 본 연구에서는 개발자들을 위한 위험관리방법으로, 요구사항추적테이블이라는 양식과 위험관리리스트간의 연결방안을 제안한다. 요구사항추적테이블은 소프트웨어 개발 생명주기 전체 과정에서 활용하고 있으며 개발자들이 사용하기 쉬운 양식이므로 요구사항추적테이블과 위험관리리스트를 연결하는 것으로 개발자들로 하여금 위험에 대한 정보를 파악하기 용이하게 하여 설계와 구현 시 관련 위험에 대해 예측이 가능하며 대처방안을 사전에 고려할 수 있다.

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ON GRADED RADICALLY PRINCIPAL IDEALS

  • Abu-Dawwas, Rashid
    • 대한수학회보
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    • 제58권6호
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    • pp.1401-1407
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    • 2021
  • Let R be a commutative G-graded ring with a nonzero unity. In this article, we introduce the concept of graded radically principal ideals. A graded ideal I of R is said to be graded radically principal if Grad(I) = Grad(〈c〉) for some homogeneous c ∈ R, where Grad(I) is the graded radical of I. The graded ring R is said to be graded radically principal if every graded ideal of R is graded radically principal. We study graded radically principal rings. We prove an analogue of the Cohen theorem, in the graded case, precisely, a graded ring is graded radically principal if and only if every graded prime ideal is graded radically principal. Finally we study the graded radically principal property for the polynomial ring R[X].

Hydrological aspects of a non-managed artificial forest watershed of Chamaecyparis obtuse Endl.

  • Otsuki, Kyoichi;Higashi, Tomohiro;Ide, Junichiro;Sato, Nobuhiro;Kume, Atsushi;Ogawa, Shigeru
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2003년도 학술발표회논문집(1)
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    • pp.81-88
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    • 2003
  • In this report, we first introduce the plan of the Japanese Council of University Experimental Forests to establish Long-Term Forest Hydrological Network, and propose the cooperation between Japan Society of Hydrology and Water Resources (JSHWR) and Korean Water Resources Association (KWRA) to fulfill the plan. Then we introduce our hydrological researches conducted in a non-managed artificial forest watershed of Kyushu University Forests in 2002. Though hydrological phenomena have not sufnciently investigated, we introduce the hydrological aspects obtained in 2002 to initiate cooperative researches on Forest Ecosystems with KWRA.

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Obstacle avoidance plan of autonomous mobile robot using fuzzy control

  • Park, Kyung-Seok;Yi, Kyung-Woong;Choi, Han-Soo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.2387-2392
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    • 2003
  • In this paper, We designed the local path planning direction algorithmusing fuzzy controller applied fuzzy logic. Algorithm decieded a direction angle by theposition of obstacle, the distance with obstacle, the progress direction of robot, the speed of vehicles and the perception area of sensor. The robot designed with proposed algorithm carried out soft moving without any particular operation, and we could observe that it had very soft curved moving as if an expert drove.

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