• 제목/요약/키워드: MAL

검색결과 899건 처리시간 0.022초

전기자동차 모터구동용 전력변환장치(PCU) 설계 및 구현 (Design and Implementation of Power Conversion Unit(PCU) for Motor of Electric Vehicle)

  • 김말수;김승모;허남억;오승진;남광희
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2012년도 추계학술대회 논문집
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    • pp.201-202
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    • 2012
  • This paper presents design and implementation of the PCU(150 kVA 3-Phase PWM Inverter for Electric Vehicles). For Implementation of the PCU, it is consist with Case, Connectors, IGBT module for PWM switching, DC-capacitor for dc-source, resolver for sensing of speed & position, and PCB board for control & gate-driver. Also, for the purpose of stable operation of the PCU in vehicle with variable torque condition in motor, current control scheme based on torque-map are developed. According to real-car test mode, the prototype of proposed the PCU is verified with performance and stability. Thus, design and implement of the PCU are discussed, and experimental results are presented in this paper.

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循環型 經濟社會의 構築을 위한 政策動向 (Policy for the Establishment of Recycling Society)

  • 오재현
    • 자원리싸이클링
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    • 제10권2호
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    • pp.3-12
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    • 2001
  • Nowadays, countries all over the world are deeply concerned about pollution in the global environment, so they are seeking various ways to adequately disposal of waste. Still, the environmental situation seems to be getting worse and worse. It is evident that such wastes and pollution have been endangering human life nestled in this globe up to the end of the 20th century. We should not, however, tolerate such human misconduct and mal-management of resources any more in the new millenium. For realizing a society that is sustainable for generations to come, it is important to establish a social system for minimizing wastes, promote re-use and recycling, and develop technology for improving recycling efficiencies, including product designs that facil-itate re-use and recycling and innovative technologies for processing wastes. In this paper, reviewing the current status of Korean waste problems, the governmental policy and specific approach for the establishment for recycling society is considered.

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열전달을 수반하는 $NH_3-H_2O$ 흡수과정에서의 Marangoni 대류 불안정성 해석 (Instability Analysis of Marangoni Convection for $NH_3-H_2O$ Absorption Process Accompanied by Heat Transfer)

  • 김제익;최창균;강용태
    • 설비공학논문집
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    • 제15권2호
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    • pp.126-131
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    • 2003
  • Convective instability driven by surface tension is analyzed in an initially quiescent water absorbing ammonia gas with heat transfer using the linear stability analysis. The propagation theory is adapted to find the critical conditions of the onset of Marangoni convection. In this theory, the solutal penetration depth is chosen as the length scale factor. The results show that the liquid layer becomes more stable with decreasing the Schmidt number and increasing the Lewis number. It is also found that there is a critical Biot number to make the liquid layer be most unstable, and there is a linear relationship between the thor-mal Marangoni number and the solutal Marangoni number.

온도차 감지 제상법과의 비교를 통한 광센서 제상법의 타당성 검증을 위한 연구 (Feasibility of the Defrost Control by Photoelectric Technology via Comparison with the Temperature Differential Defrosting Method)

  • 전창덕;김동선
    • 설비공학논문집
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    • 제26권9호
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    • pp.434-440
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    • 2014
  • Experiments were performed to verify if performance and characteristic curves obtained from the temperature differential defrosting method, where surface temperature is measured to judge defrosting condition, can be reproduced by the photoelectric technology where defrosting condition is judged by photoelectric sensors. The output voltage of a phototransistor and heating capacity, power consumption, and surface temperature of the outdoor heat exchanger are compared. The results showed that the photoelectric sensors can be used as a defrost control device. On-off control timings in temperature differential defrosting method are in good agreement with those predicted by the high and low threshold output voltages of the photoelectric sensor.

FIND THE ROOT CAUSE OF WELDING-INDUCED DISTORTION BY NUMERICAL MODELING METHOD

  • Tsai, Chon L.
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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    • pp.681-687
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    • 2002
  • The cumulative, shrinkage plastic strains and their distributions in the weld joint after completion of the welding process determine welding-induced distortion. Although the weldment undergoes many complex physical and metallurgical changes during welding, only the material plastic temperature range and its cooling history below this temperature range influence the [mal state of the cumulative shrinkage plastic strains. In addition, for structural welds, these plastic strains are uniform, except in the arc start and stop regions, along the weld. Therefore, the plastic strain-based "inherent shrinkage model" is effective and accurate to describe welding-induced distortion. This paper presents the theoretical background and numerical verification of this root cause.

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A Prototype of Robotic External Fixation System for Surgery of Bone Deformity Correction

  • Kim, Yoon-Hyuk;Joo, Sang-Min;Lee, Soon-Geul
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.2448-2450
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    • 2005
  • A robotic external fixation system for the surgery of bone deformity correction was developed to simulate the execution process of mal-unioned femur by the adjustment of the joints of the fixation system. An inverse kinematics analysis algorithm was developed to calculate the necessary rotations and translations at each joint of the robotic system. The computer graphic model was developed for validation of the analysis result and visualization of the surgical process. For given rotational and angular deformity case, the surgical execution process using the robotic system was well matched with the pre-operative planning. The final residual rotational deformities were within $1.0^{\circ}{\sim}1.6^{\circ}$ after surgical correction process. The presented robotic system with computer-aided planning can be useful for knowledge-based fracture treatment and bone deformity correction under external fixation.

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Variable selection in L1 penalized censored regression

  • Hwang, Chang-Ha;Kim, Mal-Suk;Shi, Joo-Yong
    • Journal of the Korean Data and Information Science Society
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    • 제22권5호
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    • pp.951-959
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    • 2011
  • The proposed method is based on a penalized censored regression model with L1-penalty. We use the iteratively reweighted least squares procedure to solve L1 penalized log likelihood function of censored regression model. It provide the efficient computation of regression parameters including variable selection and leads to the generalized cross validation function for the model selection. Numerical results are then presented to indicate the performance of the proposed method.

하악전돌 교정을 위한 Activator 개선에 관한 연구 (A Study on the Orthodontic Activator for Mal-Occulsion)

  • 신무학
    • 대한치과기공학회지
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    • 제5권1호
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    • pp.31-34
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    • 1983
  • 1) 종래의 activator 보다 간결한 장치. 2) 상.하악체를 고정한 불편을 덜고 심미적인 면에서 우수하였다. 3) 저작기능을 회복하여 하시에도 장착이 가능하였다. 4) 짧은 시간에 소기의 효과를 얻을 수 있었음. 장착 2주부터 교합관계 Reduction 및 순측 pushed wire bow로 수정하였고 6주부터 현저한 변화를 얻었다. 5) 복잡한 appliance가 요구되지 않았으며 비용 역시 경감되고 수번의 수정이 요구되지 않았음.

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리얼타임기반의 온라인 모바일 RPG 시스템 개발 (An On-line Mobile RPG System Development based on Real time)

  • 김송민;이말례
    • 한국정보통신학회논문지
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    • 제13권5호
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    • pp.1003-1007
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    • 2009
  • 본 논문에서는 리얼타임기반의 모바일 RPG 시스템"을 개발하였다. 이 시스템은 리얼타임 기반 게임 엔진, 게임 시스템 라이브러리, 네트워크 기반의 아이템 트레이드 서버, 클라이언트 툴들을 포함하고 있다. 기반 엔진은 미국 시장 진출을 위해 Microsoft Windows CE 기반의 스마트 폰 플랫폼을 개발하였다.