• 제목/요약/키워드: Jong-Hwa AN

검색결과 1,244건 처리시간 0.032초

앉은 자세 보정을 위한 등 근육 EMG 분류 (The back muscle's EMG classification for Sitting posture modification)

  • 홍성찬;백승화;유종현;백승은
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 D
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    • pp.2789-2791
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    • 2003
  • Today, many people are sitting on chair in their life. If a sitting posture is not correct, there is some trouble with the waist. And if it goes on long time, sometimes it cause the hurts of waist or the deformded spinal column. A crouched posture is an obstacle to breath and it give rise to drowsiness because the lack of oxygen. Sitting posture is a habit so people can't feel it oneself and look over some kind of risks. It analyzes a condition of muscles by measuring EMG of spinal both side of spin al-bones. It can have a right sitting posture by the analyzing that increasing of muscles tention in one or the other side of muscles when the posture inclines on one side or ahead.

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Zigbee 환경에서 Upper Node와의 거리를 고려한 효율적인클러스터 헤더 선출기법 (An efficient cluster header election scheme considering distancefrom upper node in zigbee environment)

  • 박종일;이경화;신용태
    • 센서학회지
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    • 제19권5호
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    • pp.369-374
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    • 2010
  • It is important to efficiently elect the cluster header in Hierarchical Sensor Network, because it largely affects on the lifetime of the network. Therefore, recent research is focused on the lifetime extension of the whole network for efficient cluster header election. In this paper, we propose the new Cluster Header Election Scheme in which the cluster is divided into Group considering Distance from Upper Node, and a cluster header will be elected by node density of the Group. Also, we evaluate the performance of this scheme, and show that this proposed scheme improves network lifetime in Zigbee environment.

자속 센서를 이용한 농형 유도전동기의 진동검출 기법 (A Method for Vibration Detection of Squirrel Cage Induction Motors Using the Flux Sensor)

  • 황돈하;이상화;한상보;선종호;강동식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 제38회 하계학술대회
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    • pp.1057-1058
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    • 2007
  • This paper proposes an alternative vibration detection method in a squirrel-cage induction motor using flux sensors. The air-gap flux will be changed when mechanical vibration occurs by bearing fault as well as broken rotor bar and air-gap eccentricity. For detecting those flux variations due to vibration, search coils are installed at stator slots. The induction motor with 380 [V], 7.5 [kW], 4 [Poles], 1,760 [rpm] ratings is used. Magnitudes and distortion of the induced voltage from flux sensors are used to discriminate faulted types. As a result, the flux sensor has been proven to be useful for vibration detection. It is compared to the result with vibration sensor as well.

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멀티톤/멀티채널의 FXLMS 알고리즘을 이용한 변압기 소음제어에 관한 연구 (A study of transformer noise control using multi-tone/multi-channel of filtered LMS algorithm)

  • 박우용;김성중;이부원;이종화;김봉기;이욱륜;이준신;안경덕;김영달
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 제38회 하계학술대회
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    • pp.379-380
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    • 2007
  • 본 연구에서는 대용량변압기의 주 소음원인 120[Hz]와 240{Hz] 및 360[Hz] 주파수에 대한 다중음을 다채널(4채널)의 FXLMS 알고리즘을 적용한 변압기 소음 감쇠시스템을 구축하고 현장실험을 통해 소음이 저감되는 것을 확인하였다.

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원자힘 주사현미경 TiO 탐침을 이용한 고온 초전도 단일채널 자속 흐름 트랜지스터의 제작 및 특성 해석 (Fabrication and Characterization of $High-T_c$ Superconducting Single Channel Flux Flow Transistor using the Atomic Force Microscope TiO Cantilever Tip)

  • 고석철;강형곤;임성훈;이종화;이해성;한병성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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    • pp.101-104
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    • 2004
  • We have fabricated a channel of superconducting flux flow transistor(SFFT) using the voltage-biased atomic force microscope(AFM) TiO tip and performed numerical simulations for the SFFT controlled by the magnetic field with a control current. The critical current density in a channel of the fabricated SFFT was decreased with the applied current by a control line. By comparing the measured with theoretical results, we showed a possibility of fabrication of an SFFT with a nano-channel using AFM anodization process technique.

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적응 FNN 제어기를 이용한 SynRM 드라이브의 효율 최적화 제어 (Efficiency Optimization Control of SynRM Drive using Adative FNN Controller for)

  • 최정식;이정철;이홍균;남수명;고재섭;김종관;정동화
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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    • pp.1459-1461
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    • 2005
  • This paper is proposed an efficiency optimization control algorithm for a synchronous reluctance motor which minimizes the copper and iron losses. The design of the speed controller based on fuzzy-neural networks(FNN) controller that is implemented using fuzzy control and neural networks. The control performance of the adaptive FNN controller is evaluated by analysis for various operating conditions. Simulation results are presented to show the validity of the proposed algorithm

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Goodness of Fit Test of Normality Based on Kullback-Leibler Information

  • Kim, Jong-Tae;Lee, Woo-Dong;Ko, Jung-Hwan;Yoon, Yong-Hwa;Kang, Sang-Gil
    • Communications for Statistical Applications and Methods
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    • 제6권3호
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    • pp.909-918
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    • 1999
  • Arizono and Ohta(1989) studied goodness of fit test of normality using the entropy estimator proposed by Vasicek (1976) Recently van Es(1992) and Correa(1995) proposed an estimator of entropy. In this paper we propose goodness of fit test statistics for normality based on Vasicek ven Es and Correa. And we compare the power of the proposed test statistics with Kolmogorov-Smirnov Kuiper Cramer von Mises Watson Anderson-Darling and Finkelstein and Schefer statistics.

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痲痺性 斜視로 因한 上瞼下垂 患者 1例에 對한 臨床的 考察 (A Case of Treatment of Blepharoptosis)

  • 유미경;정동환;박수연;최정화;김종한
    • 한방안이비인후피부과학회지
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    • 제17권2호
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    • pp.159-164
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    • 2004
  • Blepharoptosis is the state that upper eyelid sagges, palpebal fissure becomes narrow due to disorder of a levator palpebrae superioris or innervation. It affects not only the physical vision but also mental shrink. In the view of oriental medicine, there are various causes, among them mainly cause is the deficiency of spleen Gi. The other hand, we treated a patient who suffered from blepharoptosis(with headache, exotropia, dizziness) differentiate from stagnation of Gi(energy) and blood stasis with Sungihwalhyeoltang(順氣活血湯) mostly. After about 40days of Sungihwalhyeoltang(順氣活血湯) centered treatment, acupunture, we observed an improvement Based on this experience, it is considered that stagnation of Gi(energy) and blood stasis can bring about blepharoptosis.

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아연도금강판의 CO₂ 용접특성(2);용접결함의 형성기구 (CO₂ Weldability of Zn Coated Steel Sheet(2);Mechanism of Weld Defect Formation)

  • 이종봉;안영호;박화순
    • Journal of Welding and Joining
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    • 제18권2호
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    • pp.191-191
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    • 2000
  • The mechanism of the blowhole and the pit formation in lap-jointed fillet CO₂ arc welds of Zn-coated steel sheet was established by the direct observation of the gas behavior in the molten pool with the high speed camera system. Main conclusions obtained are as follows1) Some blowholes were formed by incomplete back-filling to the pits at the last stage of the solidification. This type of blowhole was formed through four stages of gas in the molten pool, incubation, explosion, back-filling and completion of back-filling stage.2) Most of the pits was back-filled at the last stage of their formation. (Received September 27, 1999)

구획화재에서 연소효율 개념에 대한 실험적 고찰 (An Experimental Study on the Combustion Efficiency Concept in Compartment Fires)

  • 황철홍;박충화;고권현;박설현;김종현
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 2010년도 추계학술발표회 자료집
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    • pp.257-260
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    • 2010
  • 실제 규모 ISO 9705 표준 화재실에서 액체연료를 대상으로 연소효율 개념에 관한 실험적 연구가 수행되었다. 특히 구획 외부에서 측정되는 총괄연소효율과 구획 내부의 고온 상층부에서 측정된 국부연소효율 개념을 비교 검토하였다. 주요 결과로서, 총괄연소효율은 총괄당량비 증가에 따라 비교적 선형적인 감소경향을 보였다. 반면에 국부연소효율은 총괄당량비가 증가함에 따라 2차 곡선의 형태로 크게 감소됨을 확인하였다. 위 결과를 통해 국부연소 효율에 대한 정보는 구획 내부의 화재현상을 이해하는데 유용한 변수임을 알 수 있었다. 또한 국부연소효율은 구획화재의 상사과정에서 중요한 변수로 사용될 수 있음을 논의하였다.

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