• 제목/요약/키워드: advancing

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전자기 가진력에 의한 BLDC 전동기의 진동 특성 해석 (Vibration Analysis for BLDC Motor by Electromagnetic Exciting Force)

  • 정희준;신판석;우성현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.118-120
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    • 2007
  • This paper deals with the vibration analysis of characteristics for BLDC motor by electromagnetic exciting force. Vibration analysis of electric machine is mainly divided into mechanical and electrical approach. However, it need to execute coupling analysis of mechanical and electrical computation because the vibration sources have relation to each other. Magnetic fields is calculated from Maxwell stress method with electromagnetic finite element method. And magnetic radial force is calculated from previous magnetic fields. With coupled electromagnetic and structure finite element, the vibratory behavior between the phase commutation advancing technique and pulse-width control is investigated in single phase brushless dc motor.

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고령사회에 대응한 보건의료체계 개편의 시급성 (The Urgency of Reforming the Healthcare System for the Aged Society)

  • 박은철
    • 보건행정학회지
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    • 제28권2호
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    • pp.105-106
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    • 2018
  • Korea, which entered the aged society in 2018, is accelerating the progress of the aged society due to the rapid decrease in birth. Although the low birth rate is the important issue, comprehensive measures to cope with the aged society should be established. In particular, the reform of the healthcare system in response to the aged society is very urgent. The reorganization of the healthcare system in response to the aged society should focus on improving the functional abilities of the elderly and should be transformed into integrated older person-centered health service. The benefit package of National Health Insurance should be diversified and appropriate payment of each benefit package should be applied. The ageism should be overcame, and it is important to recognize that the measures for the older person are investments in future society. The reform of healthcare system for older person are very urgent in Korea, which is advancing into a rapidly aged society.

주택건설공사 감리의 고객만족도에 관한 연구 -대구·경북지역을 중심으로- (A Study on the Satisfaction Degree of Clients on the Supervision in the House Construction Work - Focusing in Taegu, Kyungbuk Province -)

  • 이호;이택운
    • 한국산업융합학회 논문집
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    • 제10권4호
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    • pp.291-298
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    • 2007
  • In 1994, the house construction work was separated from design part to prevent incomplete work and to improve quality. During that time, the supervision in the house construction work has made a great development in the quantity phase, but there is no study case about the satisfaction degree of clients on the supervision job. This study presents the improvement schemes of the supervision job rationality, the revision of supervision system and supervisor's improved construction management ability. also, This paper aims at advancing our construction field and enhancing competitive power by seeking for solutions to problems and improving current system to a reasonable supervision in the house construction work comparing and analyzing by questionnaire in Taegu, Kyungbuk area. The further study will be needed about the whole Korean construction market.

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기후변화 대응 에어러솔 연구 발전을 위한 정책 연구 (Policy Studies for Advancing Aerosol Research on Climate Change in Korea)

  • 김지영;이용섭;신임철
    • 대기
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    • 제20권1호
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    • pp.49-61
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    • 2010
  • Atmospheric aerosols play a crucial role for changing climate, resulting in a wide range of uncertainty for future climate prediction. In this paper we review current international research status and trend of climate-related aerosol science. There have been carried out a number of campaigns (including ACE-Asia, TRACE-P, ABC, and so on) and special experiments with some modeling studies over Korea, East Asia, and the Northwestern Pacific to characterize the various properties (physical, chemical, optical, and radiative) of Asian aerosols and evaluate their climate forcing impacts. But some parts of the aerosol research may need to be improved, advanced, or newly launched. Especially, a chemical transport model (CTM) embedded by a general circulation model (GCM) should be developed by the national scientific community with a high research priority, actively collaborating with international community in order to estimate direct and indirect global radiative forcing due to anthropogenic and natural aerosols.

열손실에 의한 확산-열 불안정성의 가속화 (Acceleration in Diffusive-thermal Instability by Heat Losses)

  • 박준성;박정;김정수
    • 한국연소학회지
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    • 제12권2호
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    • pp.34-41
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    • 2007
  • The dynamic behaviors of counterflow non-premixed flame have been investigated experimentally to study effects of heat losses and Lewis number on edge flame oscillation, which result from the advancing and retreating edge flame motion of outer flame edge at low strain rate flame. For low strain rate flame, lateral conduction heat loss in addition to radiation heat loss could be more remarkable than the others. Oscillatory instabilities appear at fuel Lewis number greater than unity. But excessive lateral conduction heat loss causes edge flame instability even at fuel Lewis number less than unity. The excessive heat loss caused by the smaller burner diameter in which the flame length is an indicator of lateral conduction heat loss extends the region of flame oscillation and accelerates oscillatory instability in comparison to the previous study with the burner diameter of 26mm. Extinction behaviors quite different from the previous study are also addressed.

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열손실에 의한 확산-열 불안정성의 가속화 (Acceleration in Diffusive-thermal Instability by Heat Losses)

  • 박준성;박정;이기만;김정수;김성초
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2007년도 제34회 KOSCO SYMPOSIUM 논문집
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    • pp.145-152
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    • 2007
  • The dynamic behaviors of counterflow non-premixed flame have been investigated experimentally to study effects of heat losses on edge flame oscillation, which result from the advancing and retreating edge flame motion of outer flame edge at low strain rate flame. For low strain rate flame, lateral conduction heat loss in addition to radiation heat loss could be more remarkable than the others. Oscillatory instabilities appear at fuel Lewis number greater than unity. But excessive lateral conduction heat loss causes edge flame instability even at fuel Lewis number less than unity. The dramatic change of burner diameters in which flame length is an indicator of lateral conduction heat loss was applied to examine the onset condition of edge flame oscillation and flame oscillation modes. Especially, extinction behaviors quite different from the previous study were observed.

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용접구조물의 안전시공을 위한 현장기술과 용접기술 동향 (Field Welding Technology for Safe Manufacture of Welding Structure & Recent trend of Welding Technology)

  • 유택인
    • 기술사
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    • 제34권2호
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    • pp.37-41
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    • 2001
  • In recent days, welding technology developed in various field of industry, a ship, a building, a structure, a high pressure vessel ect. A welding structure should be base on a safety Welding engineers and welding technicians have a problem in acquiring welding technology, because young people avoid state of the art, beginning their careers In this field. The optimum welding state depends upon the most welding condition, mechanical properties of the base metal, welding processes and arc stability. Base on these fact, the suitable parameters of welding condition can be found through various welding experiments. Therefore, it Is very Important for welding professional engineers to take an active role In advancing new welding technology

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공공데이터를 이용한 맞춤형 영농 어플리케이션 설계 및 구현 (Design and Implementation of Customized Farming Applications using Public Data)

  • 고주영;윤성욱;김현기
    • 한국멀티미디어학회논문지
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    • 제18권6호
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    • pp.772-779
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    • 2015
  • Advancing information technology have rapidly changed our service environment of life, culture, and industry. Computer information communication system is applied in medical, health, distribution, and business transaction. Smart is using new information by combining ability of computer and information. Although agriculture is labor intensive industry that requires a lot of hands, agriculture is becoming knowledge-based industry today. In agriculture field, computer communication system is applied on facilities farming and machinery Agricultural. In this paper, we designed and implemented application that provides personalized agriculture related information at the actual farming field. Also, this provides farmer a system that they can directly auction or sell their produced crops. We designed and implemented a system that parsing information of each seasonal, weather condition, market price, region based, crop, and disease and insects through individual setup on ubiquitous environment using location-based sensor network and processing data.

Bed Combustion in a Furnace Enclosure - a Model for the MSW Incinerator

  • Ryu, Chang-Kook;Shin, Dong-Hoon;Choi, Sang-Min
    • 한국연소학회지
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    • 제7권1호
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    • pp.58-64
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    • 2002
  • The bed combustion in an incinerator interacts with the gas flow region through heat and mass transfer. Combined bed combustion and gas flow simulations are performed to investigate this coupled interaction for various operating conditions and furnace configurations. Radiation onto the bed from the furnace is interrelated with the combustion characteristics in the bed, and is also affected by the flow pattern in the gas flow region. Since the contribution of gaseous emission to the total radiation is significant, an adequate flow pattern in a well-designed furnace shape would lead to an increased heat influx on the bed, especially in the early stage of the waste combustion. Advancing the initiation point of the waste combustion can also reduce the size of the lower gas temperature region above the bed, which can be achieved by controlling operating conditions such as the waste feeding rate, the bed height and the primary air flow distribution.

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$ZnO/TiO_2$ 박막 제작과 유전율 특성 (Electric Permittivity Properties and $ZnO/TiO_2$Thin Film Fabrication)

  • 김창석;최창주;이우선;오무송;김태성;김병인
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.290-294
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    • 2001
  • In this study, ZnO is evaporated to be coated on n-type Si wafer substrate. Refractive coefficient of thin film that is evaporating TiO$_2$ onto ZnO increases linearly as thickness is getting thinner to have high value and high angle and it satisfies theoretical equation I(x)=Io exp (-$\alpha$x) theory that represents the strength of photon energy advancing through ZnO thin film. And dielectric constant of TiO$_2$ thin film evaporated onto ZnO is high and $\varepsilon$$_2$ is smaller than $\varepsilon$$_1$. The specimen TiO$_2$ thin film evaporated onto ZnO has much higher dielectric constant when photon energy is increased.

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