• 제목/요약/키워드: Thermal threshold

검색결과 294건 처리시간 0.03초

미세 유체 상 PDMS 고분자 필름의 펨토초 레이저 어블레이션 및 천공 임계치 연구 (fs-laser Ablation and Optoperforation Threshold for PDMS Thin Film on $\mu$-channel)

  • 우숙이;;윤태오;정세채;박일홍
    • 한국정밀공학회지
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    • 제27권2호
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    • pp.29-33
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    • 2010
  • We have investigated fs-laser ablation as well as optoperforation threshold of PDMS (Polydimethylsiloxane) thin lid cover on ${\mu}$-channel with changing the flow medium from water to hemoglobin. The ablation threshold is found to be independent of both PDMS thin film thickness and flow medium, but the optoperforation threshold is dependent on the films thickness. The observation that the ablation process is well described with simple two-temperature model supposed that the cover lid PDMS of $\mu$-channel be processed with minimized thermal effects by fs-laser with low laser fluence.

극저주파 자기장으로 유도한 생쥐의 통각과민에 $\alpha_2$-수용체의 관련성 (Involvement of $\alpha_2$-Receptor in Extremely Low Frequency Magnetic Field-induced Hyperalgesia in Mice)

  • 정지훈;박해자;김정수;송현주;손의동
    • 약학회지
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    • 제48권5호
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    • pp.285-290
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    • 2004
  • The purpose of this study is to prove how magnetic field (MF) acts on sympathetic neuro-transmissions using thermal response. Mice were divided into two groups and each one was exposed to MF (20 G, 24 hrs) or sham. Every vehicle or drugs were treated a half hour before the thermal response test. The pain threshold was lowered by MF (20 G, 24 hrs) alone. This reduction of pain threshold by MF was not blocked by a single treatment of $\alpha$-receptor antagonist (prazosin), $\alpha$$_2$-receptor agonist (clonidine, guanabenz), $\beta$$_1$-receptor antagonist (atenolol) or $\beta$$_1$,$\beta$$_2$-receptor antagonist (propranolol). But administration of $\alpha$$_2$-receptor antagonist (yohimbine) completely inhibited the decrease in pain threshold by MF. Moreover, it increased by high dose of yohimbine over normal condition. These results suggest that MF acts on sympathetic nerve terminal to induce hyperalgesia, in which pre-synaptic az receptor might be involved.

정량적 평가도구를 이용한 성인 요통검사 (Examination of Adult Low Back Pain Using the Quantitative Sensory Testing)

  • 이동진
    • 대한통합의학회지
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    • 제3권2호
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    • pp.39-46
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    • 2015
  • Purpose: For this study, low back pain was analyzed by determining the influences of pain threshold, proprioceptive sense, and balance ability. Method: A total of 80 college students participated in this study with 30 adults regarded as normal and 50 adults regarded as having lower back pain. Measurements for participants regarding pain threshold, proprioception, and balance ability were conducted from April 10 to May 16, 2014. Result: Results from this study show significant differences between groups for back with regards to cold pain threshold, warm pain threshold measurements. There were also significant differences in proprioception for extension measurements. Finally, there were significant differences when comparing groups regarding balance for total balance score. Conclusion: With this data, practicing physical therapists can realize that a difference may exist between the patient's perception of treatment received and the actual treatment given by professionals due to differences in threshold, proprioception and balance ability. It is important for physical therapists to understand the reliance on objective data showing the effects of threshold, proprioception and balance ability on patients with back pain.

고전압맥동전류에 의한 일차 및 이차통각과민대의 RIII 반사의 변화 (Change of RIII Reflex of Primary and Secondary Hyperalgesia Site by High Voltage Pulsed Current)

  • 김수현;최석주;이정우;정진규;김태열;김계엽
    • 대한임상전기생리학회지
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    • 제4권1호
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    • pp.1-12
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    • 2006
  • This study conducted RIII reflex measurement to examine degree of pain depending on polarity of high voltage pulsed current of primary and secondary hyperalgesia site in hyperalgesia rat by local thermal injury. Hind paw which was injury site was taken as primary hyperalgeisa site, sole which was injury adjacent site was taken as secondary hyperalgesia site, and mechanical pain threshold, thermal pain threshold and root mean square of RIII reflex were measured. This study was conducted with control group I of hyperalgesia rat at hind paw by thermal injury and experimental groups divided into cathodal high voltage treatment group II, anodal high voltage treatment group III and alternate high voltage treatment group IV, applied active electrode of high voltage pulsed current to hind paw directly, placed reference electrode on the sole of injury adjacent site and applied pulse frequency. It measured RIII reflex and obtained the following results: Root mean square of RIII reflex at primary hyperalgeisa site was significantly reduced in group II after 2 days of hyperalgesia. Group II showed significant decrease after 5 and 6 days of hyperalgesia. Root mean square of RIII reflex at secondary hyperalgesia site showed significant reduction in group II after 6 days of hyperalgesia. Consequently it was found that application of high voltage pulsed current of hyperalgesia site reduced RIII reflex at primary hyperalgeisa site and secondary hyperalgesia site by electrical stimuli. Effects by polarity of high voltage pulsed current showed the greatest reduction of pain threshold when cathodal active electrode was used.

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고온건강경보시스템 기준 설정에 관한 연구( I ) - 기준 설정 및 검증 - (Study on the Establishment of Threshold Criteria for Heat Health Watch Warning System in Korea; Part I : Establishment of Criteria and Verification)

  • 박종길;정우식;김은별
    • 한국환경과학회지
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    • 제18권7호
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    • pp.767-780
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    • 2009
  • This study investigates the standard, duration period and excess mortality of extreme heat using the standardized daily mortality data from 1991 to 2004, establishing a standard threshold Criteria for Heat Health Watch Warning System in Korea. It ultimately aims to provide the guidance in building up Heat Health Watch Warning System for Korea by suggesting the standard to quantify thermal stress from heat. The standard threshold Criteria for Heat Health Watch Warning System for Seoul metropolitan city takes into account both daily maximum temperature and daily maximum heat index(HI) and consists of four phases; caution, extreme caution, danger, and extreme danger. Extreme caution phase and danger phase are used as the advisory and warning of extreme heat, respectively. Since the nationwide distribution of the frequency of extreme heat day and the excess mortality rate shows little difference across regions, the standard threshold Criteria for Heat Health Watch Warning System for Seoul metropolitan city can be used for other regions.

폴리이미드 표면에서의 열적 스트레스에 의한 TN셀의 잔류 DC 특성 연구 (Study on the residual DC characteristic of Twisted Nematic liquid Crystal Display on the Polyimide Surface by the Thermal Stress)

  • 배유한;김상훈;황정연;강형구;이휘원;김종환;김영환;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.451-452
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    • 2005
  • In this study, the threshold voltage and the response time of thermal stressed TN-LCDs showed the same performances on none thermal stressed TN-LCDs. There was little change in TN cells. Also, while increasing thermal stress time, the transmittances of TN-LCDs on the rubbed PI surface were almost the same, But the thermal stability of TN cell was deteriorated.

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적외선 영상의 화염 검출을 위한 최적 문턱치 분석 (Analysis on Optimal Threshold Value for Infrared Video Flame Detection)

  • 정수영;김원호
    • 한국위성정보통신학회논문지
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    • 제8권4호
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    • pp.100-104
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    • 2013
  • 본 논문은 열영상 기반의 화염 검출을 위한 기존의 문턱치 설정 기법들을 분석하고 최적 문턱치 설정 방안을 제시한다. 기존의 열영상 기반의 화염검출 알고리즘들은 보통 고정 문턱치를 이용하여 화염 후보영역을 추출하고 후처리를 통해 화염 검출을 최종 판정하므로 화염 후보영역의 결정 과정은 최종 화재 검출 결과에 많은 영향을 준다. 따라서 카메라의 종류나 운영 환경에 따라 입력 영상의 대비와 밝기의 변화가 발생하기 때문에 화염 검출 문턱치는 입력영상의 특성에 연동하여 설정되어져야 한다. 따라서 최적 문턱치 설정 방안을 제시하기 위해 고정 명암도, 평균값, 표준편차 및 최대값을 이용한 문턱치 설정 기법들을 비교 분석하였다. 결론적으로 최적 문턱치는 평균과 표준편차의 합보다 크며 최대값 보다는 작은 값으로 설정 한다면 화염 검출 정확도가 기존 고정 문턱치 방식에 비해 크게 개선될 것으로 기대된다.

액정 소자의 열적 안전성에 관한 연구 (Study for thermal stability of Liquid Crystal Device)

  • 이상극;황정연;서대식;이준웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 제6회 학술대회 논문집 일렉트렛트 및 응용기술연구회
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    • pp.9-12
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    • 2004
  • In this study, we investigated about electrooptics characteristic of three kind of TN cell on the polyimide surface. Monodomain alignments of thermal stressed TN cell over temperature of liquid crystal isotropic phase were almost same that of no thermal stressed TN cells. However, the thermal stressed TN cell have many defects. Also, threshold voltage and response time of thermal stressed TN cells show same performances of no thermal stressed TN cells. There were little changes of value in these TN cells. However, transmittances of TN cells on the polyimide surface decrease with increasing thermal stress time. Finally, the residual DC voltage of the thermal stressed TN cell on the polyimide surface show decrease of characteristics as increasing thermal stress time. Therefore, thermal stability of TN cell was decreased by high thermal stress for the long times.

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프로젝션 TV 적용을 위한 액정 디스플레이의 열적 안전성에 관한 연구 (Study on Thermal Stability of Liquid Crystal Display for Projection TV Application)

  • 강희진;황정연;강형구;배유한;이휘원;김영환;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 춘계학술대회 논문집 디스플레이 광소자 분야
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    • pp.177-180
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    • 2005
  • We have investigated electro-optical characteristics in three kinds of TN cells on the polyimide surface. Transmittance of no thermal stressed TN cells were better than that of thermal stressed TN cells. Also. the threshold voltage and the response time of thermal stressed TN cells were same that of no thermal stressed TN cells. There were little change of value in these TN cells. On the other hand. transmittances of TN cells on the polyimide surface decreased by increasing thermal stress time. Moreover. the residual DC of the thermal stressed TN cells on the polyimide surface showed the characteristics of thermal stressed TN cells were weakened as increasing thermal stress temperature and time. Therefore. thermal stability of TN cells were decreased gradually by giving high thermal stress for a long time.

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The Effects of a Thermal Annealing Process in IGZO Thin Film Transistors

  • Kim, Hyeong-Jun;Park, Hyung-Youl;Park, Jin-Hong
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.289.2-289.2
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    • 2016
  • In-Ga-Zn-O(IGZO) receive great attention as a channel material for thin film transistors(TFTs) as next-generation display panel backplanes due to its superior electrical and physical properties such as a high mobility, low off-current, high sub-threshold slope, flexibility, and optical transparency. For the purpose of fabricating high performance IGZO TFTs, a thermal recovery process above a temperature of $300^{\circ}C$ is required for recovery or rearrangement of the ionic bonding structure. However diffused metal atoms from source/drain(S/D) electrodes increase the channel conductivity through the oxidation of diffused atoms and reduction of $In_2O_3$ during the thermal recovery process. Threshold voltage ($V_{TH}$) shift, one of the electrical instability, restricts actual applications of IGZO TFTs. Therefore, additional investigation of the electrical stability of IGZO TFTs is required. In this paper, we demonstrate the effect of Ti diffusion and modulation of interface traps by carrying out an annealing process on IGZO. In order to investigate the effect of diffused Ti atoms from the S/D electrode, we use secondary ion mass spectroscopy (SIMS), X-ray photoelectron spectroscopy, HSC chemistry simulation, and electrical measurements. By thermal annealing process, we demonstrate VTH shift as a function of the channel length and the gate stress. Furthermore, we enhance the electrical stability of the IGZO TFTs through a second thermal annealing process performed at temperature $50^{\circ}C$ lower than the first annealing step to diffuse Ti atoms in the lateral direction with minimal effects on the channel conductivity.

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