• 제목/요약/키워드: 홀더

검색결과 193건 처리시간 0.03초

인터넷 거버넌스 모델로서의 멀티스테이크홀더 (The Multistakeholder Model of Internet Governance)

  • 이영음
    • 인터넷정보학회지
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    • 제14권3호
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    • pp.21-34
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    • 2013
  • The multistakeholder model of Internet governance is based on the belief that the stakeholder groups should be able to agree on the rules and principles in governing the Internet space. The global expansion of the sweeping influence of the Internet has heightened the awareness of international governments on the importance of Internet governance, but since the Internet has developed mostly through voluntary participation by various groups, the organization with the greatest ability to manage the Internet space currently is ICANN(Internet Corporation for Assigned Names and Numbers), the U.S. based organization that manages the assignment of Internet domain names and IP addresses. Although ICANN has attempted to globalize its operation, governments in some nations are voicing dissatisfaction over the fact that the voice of the governments are not adequately represented within ICANN. This paper examines how the concept of multistakeholderissm has been used in WSIS(World Summit on Information Society), ICANN(Internet Corporation for Assigned Names and Numbers) and the ITU(International Telecommunication Union) as an important principle in emphasizing their roles in Internet governance.

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스프링형 블랭크홀더방식의 디프드로잉 가공에서 다이 윤곽반경이 성형성에 미치는 영향에 관한 연구 (A study on the effect of die profile radius on formability in deep-drawing process with spring-type blankholder system)

  • 이종국;강명순
    • 오토저널
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    • 제11권4호
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    • pp.35-42
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    • 1989
  • The major purpose of this paper is a study on the effect of die profile radius on the formability of spring-type blankholder system in deep drawing process. By drawing the various materials, formability is studied by means of checking the drawing force, blankholding force variation, limiting drawing ratio and wall wrinkling phenomenon. As the die profile radius increases, the maximum drawing force and maximum blankholding force decrease regardless of lubrication condition. Because better lubrication induces blankholding force to rise, spring type blankholder system is better to protect flange wrinkling phenomenon than constant pressure type. And wall wrinkling phenomenon was not detected in experimental die radius range, so the Miyakawa's upper wrinkling limit is understimated in case of material tested.

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깊은 홈 및 절단가공용 드로우어웨이식 초경공구 시스템의 설계에 관한 연구 (A Study on the Design of Throw-away Cutting Tool System for Deep Grooving or Cut-off Machining)

  • 김형철;이우영;남궁석
    • 한국정밀공학회지
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    • 제13권1호
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    • pp.123-130
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    • 1996
  • The procedure on the design of a new tungsten cabide throw-away cutting tool system for deep grooving or cut-off machining is suggested. For relieving the maximum stress level at the corner radius of the blade holder, the finite element method is used. Also the pulling test device is proposed for measuring the holding force of the insert between the blade holder and the insert considering the materials in contact and configuration parameters of the holder.

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AL합금의 용기 성형시 주름의 거동에 관한 연구 (A Study on the Behavior of Wrinkles in Cup Drawing with AL alloy)

  • 김진무;최용식
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.845-848
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    • 2002
  • The wrinkling in the flange and wall of a part is a predominent failure mode in stamping of sheet metal parts. In many cases this wrinkling may be eliminated by appropriate control of the blank holding forco(BHF), but BHF affects the draw depth. Gotoh had studied the wrinkles under 0.02mm in height. In general, the height of wrinkles could be limited under 0.2mm practically. Therefore small BHP can be allowed so that the depth of drawing could be increased. Authors research the variation of the wrinkles in flange in the course of cup drawing by using aluminium alloy Al050 and A5052.

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BD용 광픽업에서 1매대물렌즈를 이용한 DVD/CD호환 (DVD/CD Compatibility using Single Objective Lens in Optical Pickup for BD(Blu-ray Disc))

  • 윤용한;정호섭
    • 한국광학회:학술대회논문집
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    • 한국광학회 2003년도 제14회 정기총회 및 03년 동계학술발표회
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    • pp.258-259
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    • 2003
  • 보호층 0.1mm두께의 20GB이상의 광디스크를 기록·재생하는 High Density Optical System에서는 Blue-violet laser와 NA(Numerical Aperture)0.85의 High NA의 대물렌즈를 사용한 Optical Pick Up이 필요로 된다. 종래의 대물렌즈는 glass 또는 plastic제의 2매 조합 대물렌즈가 많이 사용되어지고 있는데, 이는 두 렌즈간의 거리를 일정하게 유지시키기 위한 홀더 조립시의 공차가 엄격히 요구되며, 2매 조합 대물렌즈를 구동시키기 위한 actuator의 부피와 무게를 증가시킴으로서 구동감도를 감소시키는 단점이 있다. (중략)

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빗각 증착으로 제조된 TiN 코팅층의 기계적 특성 (Mechanical Property of TiN Film Coated by Oblique Angle Deposition)

  • 양지훈;정재훈;송민아;박혜선;정재인
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2013년도 춘계학술대회 논문집
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    • pp.73-73
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    • 2013
  • 모재의 기계적인 특성을 향상하기 위한 표면처리 소재로 가장 많이 활용되고 있는 TiN을 빗각 증착으로 코팅하여 TiN 코팅층의 기계적 특성변화를 관찰하였다. 빗각 증착과 음극 아크 공정을 이용하여 TiN 코팅층을 제조하면 기울어진 주상구조가 형성되는 현상을 관찰하였다. TiN 코팅 공정 시 기판 홀더에 직류 전압을 인가하면 빗각 증착임에도 불구하고 주상정이 기울어지지 않고 기판에 수직하게 형성되는 현상을 확인하였다. 기울어진 주상정과 수직한 주상정을 다층으로 배열할 경우, TiN 코팅층의 기계적 특성 변화를 관찰할 수 있었다. 일반적인 공정으로 제조한 TiN과 비교하여 경도는 증가하고 탄성계수는 증가하지 않아 $H^3/E^2$의 값이 증가하는 현상을 관찰하였다.

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TRIZ도구를 이용한 유리병 표면부식장치 홀더 설계 (Holder Design for the Bottle Etching Machine Using TRIZ Tools)

  • 서승우;박강;김병재
    • 한국CDE학회논문집
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    • 제10권5호
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    • pp.365-374
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    • 2005
  • Most of people who are engaged in research and development find it difficult to solve the engineering problems creatively due to the lack of ideas. TRIZ is one of the emerging problem solving techniques that leads us to a very useful and clear solution. TRIZ consists of several tools such as ideal final result (IFR), physical and technical contradictions, 40 invention principles, resource, effect, etc. However, many designers think that TRIZ is hard to be applied to a design problem since there are several tools in TRIZ. Machine designers may want to see which tool is more effective than others. Thus, this paper provides sample solutions of a design problem: holder design for the bottle etching machine by applying several TRIZ tools. Difficulties in applying TRIZ to a design problem are discussed.

다중 채널 심장전기도 주 증폭기를 위한 필터 설계 (The design of filters for multi-channel cardiac activation main amplifier)

  • 한영오
    • 한국전자통신학회논문지
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    • 제5권2호
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    • pp.180-184
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    • 2010
  • 본 논문에서는 다중 채널 심장 전기도 주 증폭기의 중요한 부분인 필터를 설계하고 시뮬레이션을 통하여 성능을 분석하였다. 주 증폭기는 샘플/홀더, 가변 고역통과 필터, 노치 필터, 가변 저역통과 필터로 구성된다. 필터는 기존의 64 채널의 공간 분해능을 향상시키기 위하여 128채널을 고려하여 설계되었다.

FEM을 이용한 Micromachining용 Tool 및 Tool holder의 변형해석 (Deformation analysis of Tool and Tool holder for Micromachining by FEM)

  • 민경탁;장호수
    • 한국기계가공학회지
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    • 제9권1호
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    • pp.87-92
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    • 2010
  • Micromachining technology using a ultra-precision micromachining system is widely applied in the fields of optics, biotechnology and analytical chemistry, etc. specially in microfabrication of fresnel lens, light guide panels of TFT-LED and PDP ribs with micro-patterns, machining errors have an effect on the performance of those products. The deflection of tool and tool holder is known to be one of the very important factors that is due to machining errors in micromachining. The deflections of diamond tool and tool holder used in micro-grooving are analysed by FEM. We analysed by FEM. With an linearity valuation of FEM, deflection of tool and tool holder is calculated by using the data of cutting force which is acquired from micro-V groove machining experiments in micromachining system.

화차대차용 비틀림 흡수구조형 제륜자 홀더행거의 적용을 위한 유한요소해석 (Finite Element Analysis for Application of Torsion-free Brake Shoe Holder Hanger for the Bogie of Railway Freight Car)

  • 전응식;함영삼
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2003년도 추계학술대회 논문집(III)
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    • pp.36-41
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    • 2003
  • Among welded structure bogies in use for high speed freight car, a part of bogies manufactured in 1999 and 2000 have found problems that failure occurs in its end beam. In case of a freight car a difference of weight between empty and loading conditions are worse than in case of a passenger car. Moreover its brake system is tread brake without second suspension system. A failure of end beam is supposed to be due to loading by brake rather than vertical loading by freight. This failure can make brake system useless and may be a cause of derailment in the worst case. In this study, we have proposed a simple torsion-free brake shoe holder hanger to remove torsion of hanger bracket which is supposed to be one of causes of failure and performed finite element analyses for making trial manufactures and its application.

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