• 제목/요약/키워드: ki67

검색결과 1,490건 처리시간 0.04초

비조질강의 경도 자기제어에 미치는 합금원소의 영향 (Effect of Alloying Elements on Hardness Self-Control of Non-Heat-Treatable Steels)

  • 조기섭;권훈
    • 열처리공학회지
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    • 제30권2호
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    • pp.67-73
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    • 2017
  • Transformation behavior and hardness change were studied in five kinds of self-control steels; standard, high V, modified Ni, W, and high C-Ni steels. In the cooling rates of $10-100^{\circ}C/min$, the primary ferrite and bainite were formed, and the amount of the former increased with decreasing cooling rate. The bainite transformation temperature, Bs, was measured as 570, 560, 590, 575, and $565^{\circ}C$ in experimental steels, respectively, which was similar to the calculated temperature. The self-control, that is, the consistency in hardness, was observed, in which the hardness increased with the decrease in Bs. In the case of hot compression testing, the lower temperature deformation led to the enhancement in hardness.

온도 변화에 따른 Ribbon의 전기적 특성에 관한 연구 (A Study on The Electrical Characteristics in Ribbon by Temperature Changes)

  • 우성철;정태희;김태범;강기환;안형근;한득영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.67-67
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    • 2010
  • PV module has many power loss factor in the site. Among them, one thing is series resistance. Especially interconnection ribbon resistance is one of the power loss. In this paper, we study interconnection ribbon resistance of the PV module material. In the field, high temperature can pile ribbon resistance on the PV modules. We can do better choice in the optimum use of ribbon through checking relation of ribbon dimension and resistivity. From this point of view, different solder type and dimension was treated.

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Implementation and Tests of Antilock Braking Algorithm for a heavy vehicle

  • Lee, Ki-Chang;Jeongwoo Jeon;Donha Hwang;Kim, Yongjoo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.67.4-67
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    • 2002
  • Antilock brake System (ABS) is a essential safety equipment for modern vehicles. It prevents wheels from being locked-up when emergency braking of a vehicle is required. So it can improves directional stability of the vehicle, shortens stopping distance. Heavy Vehicles such as trucks and buses use mainly pneumatic pressures for their braking systems, where pneumatic modulators control the flow rate of compressed air thus braking pressures in the wheels. In this paper, a antilock braking algorithm which is suitable for heavy vehicles was developed. This algorithm uses limit cycle of wheels and is implemented in the ABS ECU. The developed algorithm and ECU were tested in the labo..

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Microbe-Mediated Control of Mycotoxigenic Grain Fungi in Stored Rice with Focus on Aflatoxin Biodegradation and Biosynthesis Inhibition

  • Mannaa, Mohamed;Kim, Ki Deok
    • Mycobiology
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    • 제44권2호
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    • pp.67-78
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    • 2016
  • Rice contaminated with fungal species during storage is not only of poor quality and low economic value, but may also have harmful effects on human and animal health. The predominant fungal species isolated from rice grains during storage belong to the genera Aspergillus and Penicillium. Some of these fungal species produce mycotoxins; they are responsible for adverse health effects in humans and animals, particularly Aspergillus flavus, which produces the extremely carcinogenic aflatoxins. Not surprisingly, there have been numerous attempts to devise safety procedure for the control of such harmful fungi and production of mycotoxins, including aflatoxins. This review provides information about fungal and mycotoxin contamination of stored rice grains, and microbe-based (biological) strategies to control grain fungi and mycotoxins. The latter will include information regarding attempts undertaken for mycotoxin (especially aflatoxin) bio-detoxification and microbial interference with the aflatoxin-biosynthetic pathway in the toxin-producing fungi.

스위스 치즈 모델을 적용한 철도 감전사고 발생형태에 관한 연구 (A Study on the Form of Electric Shock Accident Using Swiss Cheese Model)

  • 유기성;김재문
    • 전기학회논문지
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    • 제67권12호
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    • pp.1711-1716
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    • 2018
  • Unlike conventional transmission and distribution lines, catenary system for operating electric railway vehicles are composed of multi-conductor groups (feeder line, contact wire, messenger wire, protection wire) and are used for railway employees, public or passengers in the station yards. Electric shock hazards are exposed and electric shocks such as death or serious injury are occurring in electric railway vehicles, railway high-voltage distribution lines, and catenary system. In order to analyze the types of electric shock accidents on railway by systematic approach method, we modeled 'unsafe behavior classification' method using swiss cheese model. Based on this method, we derived the type of electric shock accidents about railway accidents during the last 5 years by analyzing the frequency of occurrence of human errors and unsafe acts, laws and regulations related to violations, and so on.

철도차량기지용 단권변압기의 전압강하에 대한 이론적 고찰 (A Theoretical Study on Voltage Drop of Auto-Transformer for Railway Vehicle Base)

  • 유기성;김재문
    • 전기학회논문지
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    • 제67권12호
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    • pp.1723-1728
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    • 2018
  • In order to investigate the voltage drop compensation effect of AT for domestic railway vehicle base, the parameters of AT voltage drop of railroad car base are Z3 (Impedance of feeder line), Xn ( Distance from railroad vehicle to AT to SS), and Dn (distance between both ATs of railway vehicle).In addition, when installed in a SSP for a railway vehicle base, there is no AT and feeder line in the railway vehicle base except for the SSP for the main line and the SSP for the railway vehicle base, so that if zero or ignored, the AC single-phase two- It can be confirmed that it becomes a form.