• 제목/요약/키워드: Protect

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절삭유 공급 방식의 신뢰성 평가 기술 (Reliability Evaluation Technology of Metal Working Fluids Supply Method)

  • 강재훈;송준엽;이승우;박화영;박종권
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2002년도 춘계학술대회 논문집
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    • pp.206-208
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    • 2002
  • Metalworking fluids (MWFs) are fluids used during machining and grinding to prolong the life of the tool , carry away debris, and protect the surfaces of work pieces. These fluids reduce friction between the cutting tool and the work surface, reduce wear and galling, Protect surface characteristics, reduce surface adhesion or welding and carry away generated heat. Workers can be exposed to MWFs by inhaling aerosols (mists) and by skin contact with the fluid. Skin contact occurs by dipping the hands into the fluid, splashes, or handling workpieces coated with the fluids. The amount of mist generated (and the result ins level of exposure) depends on many factors. To reduce the potential health risks associated with occupational exposures to MWFs, it is required to establish optimum MWFs supply method and condition with minimum Quantity in all over the mechanical machining field including high speed type heavy cult ing process.

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절삭유 공급 방식의 최적화를 위한 실험적 연구 (An Experimental Study on the Proper Supply Method of Metal Cutting Coolant)

  • 강재훈;송준엽;최종호
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 추계학술대회 논문집
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    • pp.977-980
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    • 2004
  • Metalworking fluids (MWFs) are fluids used during machining and grinding to prolong the life of the tool, carry away debris, and protect the surfaces of work pieces. These fluids reduce friction between the cutting tool and the work surface, reduce wear and galling, protect surface characteristics, reduce surface adhesion or welding and carry away generated heat. Workers can be exposed to MWFs by inhaling aerosols (mists) and by skin contact with the fluid. Skin contact occurs by dipping the hands into the fluid, splashes, or handling workpieces coated with the fluids. The amount of mist generated (and the resulting level of exposure) depends on many factors. To reduce the environmental pollution wastes and the potential health risks associated with occupational exposures to MWFs, it is required to establish optimum MWFs supply method and condition with minimum quantity in all over the mechanical machining field including high-speed type heavy cutting process.

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전자상거래하에서의 전자서명의 보안성에 관한 연구 (A Study on the Transaction Security of Electronic Signature in the Electronic Commerce)

  • 전순환
    • 정보학연구
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    • 제1권2호
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    • pp.229-244
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    • 1998
  • 전자문서 전자영수증 대금결제 서명 및 상호인증 등 전자상거래의 거의 모든 영역에서 사용되고 있는 전자서명의 경우에는 특히, 거래 상대방을 확인할 수 있는 확인 절차와 더불어 안전하고 신뢰성 있는 보안시스템의 구축을 위한 암호화가 필요하게 된다. 따라서 전자서명의 일반적 고찰과 관련하여 각국에서 제정되고 있는 법규는 물론 전자서명에 따른 보안문제를 고찰하고자 한다.

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협곡풍에 의한 송전선로점퍼선 횡진고장 방지대책 (Protection Measure of Transmission Jumper Line by Gap Winds)

  • 고봉언;표광찬;박재형;강범영;정현종
    • 전기학회논문지
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    • 제58권6호
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    • pp.1071-1077
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    • 2009
  • Because several winds cause the a fault of transmission supply, KEPCO trys to protect the the trouble and supply the power stably. Kepco find out the weak mountains by winds and strengthen the power equipment annually. Power quality is the competition power in the international world and satisfy the customer using th power Therefore this paper deals with the fault relation between winds and transmission line.

패트리어트 (patriot) 미사일의 최적 배치 (Optimal deployment strategy of patriot missile)

  • 김영휘;김성인;오원민
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1994년도 춘계공동학술대회논문집; 창원대학교; 08월 09일 Apr. 1994
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    • pp.29-37
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    • 1994
  • It is reported that north Korea has already developed 1,500 to 2,000-km-range Scud missile. As a defensive strategy against Scud attack on military and civilian facilities the military authorities are considering deployment of Patriot missile. This paper deals with its optimal deployment strategy. In this problem a Patriot missile which has multiple-facility responsibility may be able to protect each of its assigned facilities only with a certain probability, not absolute protection, and it may not be adequate to have only a single missile protect a facility, either because of its operational reliability or because of its limited availability at any given point in time. We formulate this problem into the probabilistic partial set covering model developed by Sherali and Kim. The applicability, verification and validation of the model are tested via an abbreviated case study.

중요문화재의 소방안전 진단 및 예방관리 시스템 모델 연구 -경기도내 전통적인 목조건축물 중심으로- (A Study of Prevention Management System Model and Fire Safety Diagnose for Cultural Heritages -Based on Traditional wooden structure in kyong gi-Do-)

  • 정길흥
    • 기술사
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    • 제32권6호
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    • pp.148-157
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    • 1999
  • As cultural Heritages are source of the national history and a life transition, their extinction is a fatal shock as result of cutoff the genealogy of the creative national spirit. So, we have necessarily to protect them, and to get the duty and the responsibility which the cultural inheritance hands over tnem to descendants with preserving and meaning safely at present time. In these days, the risk of fire in the Cultural Heritages building is increased because of rash changing environments from the indiscreet development of them. Accordingly, in order to get the original transmission of the Cultural Heritages, this paper involves being intensive the fire safety information of the Cultural Heritage in kyonggi-do province, analyzing their diagnoses, and studying a Fire Safety Prevention Management model to protect and to maintain them continuously. Therefore, it is to contribute from this approach to collecting fire safety information, analyzing diagnostic problems in fire accidents, and to manage the prevention method for protecting and maintaining the Cultural Heritages.

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국립공원 경관 가치의 증진방안 (Aesthetic Value of Korean National Parks' Landscape: Its Appreciation and Protection Strategies)

  • 박경
    • 환경영향평가
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    • 제12권5호
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    • pp.369-382
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    • 2003
  • Natural resources managers have considered the landscape without detailed consideration of aesthetic values of the landscape and geomorphological significance of unique landforms. Since EIA system was introduced in 1981, values associated with landscape protection have been neglected at best compared with those values traditionally attributed to environmental protection, including clean air, water quality and species protection. Black top highways are being built without consideration of harmful effects to the sea cliffs. Sea walls and tetrapod are being installed to protect the coastal towns and fish markets for tourist. However, beach itself are experiencing accelerated erosion due to the shortage of proper coastal engineering expertise. Hotels and condominiums are under construction on a massive scale around the national parks, which substitute the scenic ridges with concrete profiles. To protect the scenic beauty of national parks, their design and construction material should be more harmonious with the surroundings. Therefore, visual impact assessment should be applied both within the national park boundary and beyond to enhance the aesthetic values of national parks.

무인화 무기체계의 안정적인 운용을 위한 Cybersecurity 및 Anti-Tamper의 적용 (Applying Cybersecurity and Anti-Tamper Methods for Secure Operating of Unmanned Weapon Systems)

  • 이민우
    • 시스템엔지니어링학술지
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    • 제16권1호
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    • pp.36-42
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    • 2020
  • Due to the population of the Republic of Korea is getting less, the shortage of available troops has become a big issue. In response to this, the need for Unmanned weapon systems is rising. To operate an Unmanned weapon system near borderlines or low altitude, it is necessary to protect not only the system itself but also operational information communicated between the Unmanned system and control station, so that they should be safe using Cybersecurity measures. Besides, it is critical to protect a few core technologies applied to Unmanned weapon systems throughout the Anti-Tamper measures. As the precedent studies only focus partially, Cybersecurity or Anti-Tamper, it is acknowledged that comprehensive studies are needed to be conducted. This study is to incorporate both concepts into Korea's defense acquisition process. Specifically, we will outline the concepts and needs of Cybersecurity and Anti-Tamper, and briefly present ways to apply them simultaneously.

Provil과 cerrobend을 이용한 electron 차폐물 제작 (The Fabrication of Internal Shielding using Provil and Cerrobend)

  • 김종화;이강현;손정혜
    • 대한방사선치료학회지
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    • 제8권1호
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    • pp.37-39
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    • 1996
  • The skin cancer is a highly curable disease which frequently occurs in the head and neck region exposed to the sun. When the eyelid is treated usually eye shield made of lead is used to protect the eyeball as a internal shield. For the same reason on internal shield should be used when the nose is treated when electron to protect the nasal mucosa. Our hospital made an internal shield for the treatment of the skin cancer on the nose using provil and cerrobend. The characteristics of the internal shield were examined.

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CRASHWORTHY DESIGN AND EVALUATION ON THE FRONT-END STRUCTURE OF KOREAN HIGH SPEED TRAIN

  • Koo, J.S.;Youn, Y.H.
    • International Journal of Automotive Technology
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    • 제5권3호
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    • pp.173-180
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    • 2004
  • An intensive study was conducted for the crash worthy structural design of the recently developed Korean High Speed Train (KHST). Two main design concepts were set up to protect both crews and passengers from serious injury in heavy collision accidents, and to reduce damage to the train itself in light collision accidents. A collision against a movable 15-ton rigid obstacle at 110 kph was selected from train accident investigations as the accident scenario for the heavy collisions. A train-to-train collision at the relative velocity of 16 kph was used for the light collision. The crashworthiness behaviors of KHST were numerically evaluated using FEM. Analysis results using 1-D collision dynamics model of the full rake consist and 3-D shell element model of the front end structure showed good crashworthy responses in a viewpoint of structural design. Occupant analyses and sled tests demonstrated that KHST performed well enough to protect occupants under the considered accident scenarios. Finally our numerical approaches were evaluated by a real scale collision test.