• 제목/요약/키워드: Response Threshold

검색결과 423건 처리시간 0.031초

Electrooptic Response of Reflective Liquid Crystal Cell

  • Lee, Geon-Joon;C. H. Oh;Lee, Y. P.;T. K. Lim
    • 한국진공학회지
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    • 제12권S1호
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    • pp.33-35
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    • 2003
  • The electrooptic properties of the reflected light in a reflective mode, $45^{\circ}C$twisted nematic liquid crystal (TNLC) cell were investigated in the voltage regions near and away from the Freedericksz transition threshold. The measured reflectivity away from the threshold voltage ($V_th$) could not be described by the model which assurnes a constant tilt angle as well as a linearized distribution of twist angle across the cell, although the data are well fitted near $V_th$. We found that in the voltage region away from $V_th$, the model considering the distributions of the tilt angle and the twist angle should be applied for the calculation of the reflectivity. The director-axis distributions were obtained from the numerical integration of the Euler-Lagrange equation.

소음으로 인한 청력소실에 대한 마늘 추출물 diallyl disulfide(DADS)의 효과 (Protective Effect of Diallyl disulfide(DADS) from Garlic Extract on Noise Induced Hearing Loss in the Guinea pigs)

  • 윤민영;조남근;황우준;장철호
    • Journal of Acupuncture Research
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    • 제19권2호
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    • pp.105-113
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    • 2002
  • Objective : The purpose of this study is to investigate the protective effect of DADS on the noise induced hearing loss Methods : Twenty healthy guinea pigs (DADS pretreated group and control) were exposed to 100dB a collected environmental noise for 9 hours. An auditory evoked brainstem response (ABR) threshold was measured before and after a noise exposure. For morphological study, cochlea was studied by scanning electron microscope (SEM). Results : The DADS pretreated group showed statistically significant less changes in ABR threshold and SEM findings compared the control group. Conclusion : From these results suggest that the DADS from garlic may have a protective effect in noise induced hearing loss.

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수종 생약 수증기 증류물의 탈취작용 (Deodorizing Responses of the Steam Distillate from Some Medicinal Plants)

  • 신국현;이은방;송영진;김운자
    • 생약학회지
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    • 제23권3호
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    • pp.153-157
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    • 1992
  • The deodorizing responses of the steam distillate from some medicinal plants(G-3) on three representative malodors were evaluated by estimating the best estimate threshold(BET) of odor responses. With a single spray of G-3, the BETs of malodors such as ammonia, acetic acid, and ethyl acetate were found to increase 4.11, 32.6 and 13.1 fold, respectively, which indicated G-3 possessed a potent deodorizing activity. The deodorizing potency of G-3 was also demonstrated to be as high as and even higher than those of the commercial deodorizing agents.

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Stochastic procedures for extreme wave induced responses in flexible ships

  • Jensen, Jorgen Juncher;Andersen, Ingrid Marie Vincent;Seng, Sopheak
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제6권4호
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    • pp.1148-1159
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    • 2014
  • Different procedures for estimation of the extreme global wave hydroelastic responses in ships are discussed. Firstly, stochastic procedures for application in detailed numerical studies (CFD) are outlined. The use of the First Order Reliability Method (FORM) to generate critical wave episodes of short duration, less than 1 minute, with prescribed probability content is discussed for use in extreme response predictions including hydroelastic behaviour and slamming load events. The possibility of combining FORM results with Monte Carlo simulations is discussed for faster but still very accurate estimation of extreme responses. Secondly, stochastic procedures using measured time series of responses as input are considered. The Peak-over-Threshold procedure and the Weibull fitting are applied and discussed for the extreme value predictions including possible corrections for clustering effects.

전기 치수 자극에 의해 유발된 동통 반응의 측정 (Measurement of the pain responses induced by electric pulp test)

  • 안선회;남기창;김수찬;김재성;이승종;김덕원
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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    • pp.727-730
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    • 2003
  • Electric pulp test is a method to examine the vitality of dental pulp using the electrical stimulation. During the pulp test, the current stimulates intradental nerve, and makes patients painful. Some studies were accomplished to measure the responses of subjects by stimulating over the sensory threshold. In this study, we examined the time delay between pain feeling and stimulation stop in clinical situation. And we measured the activated responses(EMG in anterior belly of digastric muscle, voice, and finger span). As a result, it was verified that the minimum and maximum delay was EMG and voice, respectively. By reducing the excessive stimulus time, the unnecessary pain can be minimized using EMG that has the minimum delay.

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통각유발물질에 의한 척수후각세포의 반응에 미치는 Clonidine의 영향 (Effect of Clonidine on the Changes in Dorsal Horn Cell Activity Induced by Chemical Algogenics)

  • 이광훈;김진혁;신홍기;김기순
    • The Korean Journal of Physiology
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    • 제22권2호
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    • pp.245-257
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    • 1988
  • The present study was undertaken to investigate the effect of clonidine on the response of the dorsal horn cells to intra-arterially administered bradykinin $(BK:40{\mu}g)$ and $K^+(4mg)$ in spinal cats and cats with intact spinal cord. The change in the activities of low threshold (LT), high threshold (HT) and wide dynamic range (WDR) cells induced by BK and $K^+$ were determined before and after treatment of animals with clonidine. Also studied was mechanism of inhibitory action of clonidine on the responses of dorsal horn cells to the chemical algogenics. Number of WDR cell responded to intra-arterially administered BK and $K^+$ was greater in spinal animals than in cats with intact spinal cord. Following administration of BK or $K^+$ no change was observed in the activity of LT cell whereas activity of HT cell increased invariably. The increased response of HT cell to BK and $K^+$ was markedly suppressed by clonidine. On the other hand, such inhibitory actions of clonidine were almost completely blocked by yohimbine. The majority of WDR cells were activated by $K^+$ while response of WDR cells to BK was diverse (excitatory, inhibitory or mixed). These results indicate that clonidine inhibits responses of the dorsal horn cells not only to thermal or mechanical stimulations but also to chemical algogenics, and that the inhibitory action of clonidine is generally mediated through excitation of ${\alpha}_2-adrenoreceptors$.

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구조물의 안전성 모니터링을 위한 통계/확률기반 적응형 임계치 설정 알고리즘 개발 (Development of Statistical/Probabilistic-Based Adaptive Thresholding Algorithm for Monitoring the Safety of the Structure)

  • 김태헌;박기태
    • 한국구조물진단유지관리공학회 논문집
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    • 제20권4호
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    • pp.1-8
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    • 2016
  • 최근의 건축물은 복합적인 기능과 형태를 보이고 있으며, 크기가 거대해짐에 따라 구조물 건전성 감시(Structural Health Monitoring)기술의 수요 또한 증가하고 있다. 구조물마다 고유한 동특성을 가지고 있으며, 다양한 외력의 영향을 받기 때문에 구조물의 건전성을 평가하는 다양한 방법들이 연구되고 있다. 전문가에 의지하여 접근 가능한 지점에 대한 육안 검사 및 비파괴 검사를 벗어나 사각지대가 없는 온라인 계측 시스템의 구비와 함께 자동으로 위험요소를 검출하는 시스템이 요구되고 있다. 본 연구에서는 비선형적인 구조물의 응답을 고려하기 위해 관리도 기법, 평균제곱근편차, 일반 극치 분포 등과 같은 통계적 기법을 이용하여 이상거동을 판별에 활용할 수 있는 신호 특징 추출과 적응형 임계치 설정 알고리즘을 제안하였으며, 강제진동 실험과 실제 운용중에 있는 구조물의 지진 계측 시스템의 가속도 응답을 이용하여 성능을 검증하였다.

특발성 돌발성 난청으로 오인된 청신경 종양 1례 (A Case Report of Vestibular Schwannoma Misdiagnosed as Idiopathic Sudden Sensorineural Hearing Loss)

  • 고혜연;김재호;이마음;김민희
    • 한방안이비인후피부과학회지
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    • 제34권3호
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    • pp.80-91
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    • 2021
  • 1. 청신경 종양 진단의 표준 검사는 두부 가돌리늄 조영 증강 자기 공명 영상 촬영이며, 경제적 문제 등으로 조영 증강 자기 공명 영상 촬영이 어려울 경우에는 청성 뇌간 반응(auditory brainstem response) 검사를 시행할 수 있다. 2. 특발성 돌발성 난청으로 진단 받은 후, 한의 의료기관에 내원한 환자에서도 기존 검사결과를 검토하여 후미로성 질환을 배제한 후 치료를 시작해야한다. 3. 비조영 증강 자기 공명 영상 촬영을 통해 후미로성 질환을 배제한 환자에서도 임상적으로 후미로성 질환이 의심되는 경우에는 표준 검사인 가돌리늄 조영 증강 자기 공명 영상 재촬영을 통해 청신경종을 감별하는 것이 바람직하다. 4. 청신경 종양에서 한방 치료를 표준 치료와 병행하여 제반 증상에 대한 관리를 기대해 볼 수 있다.

흰쥐의 척수에서 Glutamate가 매개하는 Nociceptive Response에 있어서 Protein kinase C의 관련성 (The Involvement of Protein kinase C in Glutamate-Mediated Nociceptive Response at the Spinal Cord of Rats)

  • 김성정;박전희;이영욱;양성준;이종은;이병천;손의동;허인회
    • 약학회지
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    • 제43권2호
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    • pp.263-273
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    • 1999
  • When glutamate was infected intrathecally, the result is similar to those produced by TPA injected. The involvement of protein kinase C (PKC) in the nociceptive responses in rat dorsal horn neurons of lumbar spinal cord was studied. In test with formalin, a PKC inhibitor (chelerythrine) inhibited dose-dependently the formalin-induced behavior response. Neomycin also inhibited it significantly. But, a PKC activator (12-O-tetradecanoylphorbol-13-ester, TPA) showed reverse effect. When gluatamate was injected intrathecally, we observed the result is smilar to those produced by TPA injection. On the other hand, intrathecal injection of glutamate induced thermal and mechanical hyperalgesia. In Tail-flick test, we examined the involvement of PKC on the glutamate-indeced thermal hyperalgesia. Chelerythrine showed an inhibitory effect and TPA enhanced thermal response. Glutamate decreased the mechanical threshold significantly. A pretreatment of chelerythrine and neomycin inhibited glutamate-induced mechanical hyperalgesia, but the effect of neomycin was not significant. TPA had little effect on the mechanical nociceptive response. These results suggest that the PKC activation through metabotropic receptor at postsynaptic region of spinal cord dorsal horn neurons may influence on the persistent nociception produced by chemical stimulation with formalin, thermal and mechanical hyperalgesia induced by glutamate.

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Neuroticism and pain catastrophizing aggravate response to pain in healthy adults: an experimental study

  • Banozic, Adriana;Miljkovic, Ana;Bras, Marijana;Puljak, Livia;Kolcic, Ivana;Hayward, Caroline;Polasek, Ozren
    • The Korean Journal of Pain
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    • 제31권1호
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    • pp.16-26
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    • 2018
  • Background: The aim of this study was to investigate the association between neuroticism, pain catastrophizing, and experimentally induced pain threshold and pain tolerance in a healthy adult sample from two regions of the country of Croatia: the island of Korcula and city of Split. Methods: A total of 1,322 participants were enrolled from the Island of Korcula (n = 824) and the city of Split (n = 498). Participants completed a self-reported personality measure Eysenck Personality Questionnaire (EPQ) and pain catastrophizing questionnaire Pain Catastrophizing Scale (PCS), followed by a mechanical pain pressure threshold and tolerance test. We have explored the mediating role of catastrophizing in the relationship between neuroticism and pain intensity. Results: The results showed that pain catastrophizing partially mediated the relationship between neuroticism and pain intensity, suggesting the importance of pain catastrophizing in increasing vulnerability to pain. The results also indicated gender-related differences, marked by the higher pain threshold and tolerance in men. Conclusions: This study adds to the understanding of the complex interplay between personality and pain, by providing a better understanding of such mechanisms in healthy adults.