• Title/Summary/Keyword: Thermal threshold

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

  • Woo, Suk-Yi;Sidhu, M.S.;Yoon, Tae-Oh;Jeoung, Sae-Chae;Park, Il-Hong
    • Journal of the Korean Society for Precision Engineering
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    • v.27 no.2
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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.

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

  • 정지훈;박해자;김정수;송현주;손의동
    • YAKHAK HOEJI
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    • v.48 no.5
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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.

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

  • Lee, Dongjin
    • Journal of The Korean Society of Integrative Medicine
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    • v.3 no.2
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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.

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

  • Kim, Su-Hyon;Choi, Sug-Ju;Lee, Jung-Woo;Jeong, Jin-Gyu;Kim, Tae-Youl;Kim, Gye-Yeop
    • Journal of the Korean Academy of Clinical Electrophysiology
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    • v.4 no.1
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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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Study on the Establishment of Threshold Criteria for Heat Health Watch Warning System in Korea; Part I : Establishment of Criteria and Verification (고온건강경보시스템 기준 설정에 관한 연구( I ) - 기준 설정 및 검증 -)

  • Park, Jong-Kil;Jung, Woo-Sik;Kim, Eun-Byul
    • Journal of Environmental Science International
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    • v.18 no.7
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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.

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

  • Bae, Yu-Han;Kim, Sang-Hoon;Hwang, Jeoung-Yeon;Kang, Hyung-Ku;Lee, Whee-Won;Kim, Jong-Hwan;Kim, Young-Hwan;Seo, Dae-Shik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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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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Analysis on Optimal Threshold Value for Infrared Video Flame Detection (적외선 영상의 화염 검출을 위한 최적 문턱치 분석)

  • Jeong, Soo-Young;Kim, Won-Ho
    • Journal of Satellite, Information and Communications
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    • v.8 no.4
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    • pp.100-104
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    • 2013
  • In this paper, we present an optimal threshold setting method for flame detection of infrared thermal image. Conventional infrared flame detection methods used fixed intensity threshold to segment candidate flame regions and further processing is performed to decide correct flame detection. So flame region segmentation step using the threshold is important processing for fire detection algorithm. The threshold should be change in input image depends on camera types and operation conditions. We have analyzed the conventional thresholds composed of fixed-intensity, average, standard deviation, maximum value. Finally, we extracted that the optimal threshold value is more than summation of average and standard deviation, and less than maximum value. it will be enhance flame detection rate than conventional fixed-threshold method.

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

  • Lee, Sang-Keuk;Hwang, Jeoung-Yeon;Seo, Dae-Shik;Lee, Joon-Ung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.04a
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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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Study on Thermal Stability of Liquid Crystal Display for Projection TV Application (프로젝션 TV 적용을 위한 액정 디스플레이의 열적 안전성에 관한 연구)

  • Kang, Hee-Jin;Hwang, Jeoung-Yeon;Kang, Hyung-Ku;Bae, Yu-Han;Lee, Whee-Won;Kim, Young-Hwan;Seo, Dae-Shik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.05a
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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
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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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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