• 제목/요약/키워드: Bias-stress

검색결과 291건 처리시간 0.036초

화상 환자에서 신속 순차 시각 제시를 이용한 주의깜빡임에 관한 예비연구 (A Preliminary Study of Attentional Blink of Rapid Serial Visual Presentation in Burn Patients with Posttraumatic Stress Disorder)

  • 김대희;전보라;서정훈;조용석;임해준;허준;김도헌;전욱;김종현;정명훈;최인근;이병철
    • 생물정신의학
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    • 제17권2호
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    • pp.79-85
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    • 2010
  • Objectives : Trauma patients have attentional bias which enforces traumatic memories and causes cognitive errors. Understanding of such selective attention may explain many aspects of the posttraumatic stress disorder(PTSD) symptoms. Methods : We used the rapid serial visual presentation(RSVP) method to verify attentional blink in burn patients with PTSD. International affective picture system(IAPS) was used as stimuli and distracters. In the 'neutral test', patients have been presented series of pictures with human face picture as target stimuli. Each picture had 100ms interval. However the distance between target facial pictures was randomized and recognition of second facial picture accuracy was measured. In the 'stress test', the first target was stress picture which arouses patient emotions instead of the facial picture. Neutral and Stress tests were done with seven PTSD patients and 20 controls. In '85ms test' the interval was reduced to 85ms. The accuracy of recognition of second target facial picture was rated in all three tests. Eighty-five ms study was done with eighteen PTSD patients. Results : Attentional blinks were observed in 100-400ms of RSVP. PTSD patients showed increased recognition rate in the 'stress test' compared with the 'neutral test'. When presentation interval was decreased to 85 ms, PTSD patient showed decrease of attentional blink effect when target facial picture interval was 170ms. Conclusion : We found attentional blink effect could be affected by stress stimulus in burn patients. And attentional blink may be affected by stimulus interval and the character of stimulus. There may be some other specific mechanism related with selective attention in attentional blink especially with facial picture processing.

주성분 회귀분석 및 인공신경망을 이용한 AE변수와 응력확대계수와의 상관관계 해석 (Analysis on Correlation between AE Parameters and Stress Intensity Factor using Principal Component Regression and Artificial Neural Network)

  • 김기복;윤동진;정중채;박휘립;이승석
    • 비파괴검사학회지
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    • 제21권1호
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    • pp.80-90
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    • 2001
  • AE 신호와 재료의 기계적 물성과의 관계를 정량적으로 제시할 수 있는 방법을 개발하였다. 재료의 여러 가지 기계적 성질들 중 피로균열 거동에 관련된 응력확대계수를 중심으로 AE 신호와 같은 다변량 데이터의 처리에 많이 사용되고 있는 주성분 회귀분석과 비선형적 문제 해결에 적합한 신경회로망 기법을 이용하였다. 이를 위하여 강교량 부재인 SWS490B 강에 대한 피로균열전파 실험을 수행하였으며 표준 CT 시편에 대한 피로균열진전 시 발생하는 AE 신호의 각 변수와 응력확대계수와의 관계를 고찰하였다. 통계분석 방법인 변수선택법을 적용한 결과 AE 카운트(RC), 에너지(EN), 신호지속시간(ED)의 각각에 대한 유의성이 높은 것으로 나타났으나 전반적으로 전체 AE 변수를 모두 이용할 경우 통계적 유의성이 높은 것으로 나타났다. 부재의 반복하중 시 발생하는 피로균열진전을 정량적으로 도출할 수 있는 응력확대계수 추정모델을 개발하고 평가하였다. 미지 시료에 대하여 개발된 모델의 응력확대계수 예측 성능을 분석한 결과 주성분 회귀모델과 인공신경망 모델 모두 우수한 예측성능을 나타내었으나 전반적으로 인공신경망 모델이 주성분 회귀모델보다 다소 양호한 것으로 분석되었다.

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Suppression of Gate Oxide Degradation for MOS Devices Using Deuterium Ion Implantation Method

  • Lee, Jae-Sung
    • Transactions on Electrical and Electronic Materials
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    • 제13권4호
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    • pp.188-191
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    • 2012
  • This paper introduces a new method regarding deuterium incorporation in the gate dielectric including deuterium implantation and post-annealing at the back-end-of-the process line. The control device and the deuterium furnace-annealed device were also prepared for comparison with the implanted device. It was observed that deuterium implantation at a light dose of $1{\times}10^{12}-1{\times}10^{14}/cm^2$ at 30 keV reduced hot-carrier injection (HCI) degradation and negative bias temperature instability (NBTI) within our device structure due to the reduction in oxide charge and interface trap. Deuterium implantation provides a possible solution to enhance the bulk and interface reliabilities of the gate oxide under the electrical stress.

Improvement on the Stability of Amorphous Indium Gallium Zinc Oxide Thin Film Transistors Using Amorphous Oxide Multilayer Source/Drain Electrodes

  • Lee, Sang Yeol
    • Transactions on Electrical and Electronic Materials
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    • 제17권3호
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    • pp.143-145
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    • 2016
  • In order to find suitable source and drain (S/D) electrodes for amorphous InGaZnO thin film transistors (a-IGZO TFTs), the specific contact resistance of interface between the channel layers and various S/D electrodes, such as Ti/Au, a-IZO and multilayer of a-IGZO/Ag/a-IGZO, was investigated using the transmission line model. The a-IGZO TFTs with a-IGZO/Ag/a-IGZO of S/D electrodes had good performance and low contact resistance due to the homo-junction with channel layer. The stability was measured with different electrodes by a positive bias stress test. The result shows the a-IGZO TFTs with a-IGZO/Ag/a-IGZO electrodes were more stable than other devices.

호텔 종사원의 조직몰입과 서비스품질의 관계 및 성의 조절효과 (The relationship between organizational commitment and service quality, and the moderating effect of gender in hotel)

  • 안관영
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2006년도 춘계공동학술대회
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    • pp.147-156
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    • 2006
  • Since IMF system was introduced once, downsizing has been usual phenomenon in business sphere. Downsizing influences the unemployed, and also the survivors such as in job stress, communication bias, lower organizational commitment and so on. This paper reviewed the relationship between organizational commitment and service quality, and the moderating effect of sex in hotel. Based on the responses from 494 hotel employees, the results of multiple regressional analysis showed that affective OC and normative OC have affirmative effects on service quality. The results of moderating analysis showed that continuance OC has an affirmative interactive-effect on responsiveness, assurance, and empathy with gender, and affective OC an negative interactive-effect on assurance.

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드레인 전압 바이어스에 대한 미세결정 실리콘 박막 트랜지스터의 전기적 안정성 분석 (Effect of drain bias stress on the stability of nanocrystalline silicon TFT)

  • 지선범;김선재;박현상;한민구
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1281_1282
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    • 2009
  • ICP-CVD를 이용하여 inverted staggered 구조를 갖는 미세결정 실리콘 (Nanocrystalline Silicon, nc-Si) 박막 트랜지스터(Thin Film Transistor, TFT)를 제작하였다. 또한, 소자의 특성과 전기적 안정성을 평가하였다. 실험 결과는 짧은 채널 길이를 갖는 nc-Si TFT가 긴 채널 길이의 소자보다 같은 드레인 전압 바이어스 하에서 덜 열화 됨을 알 수 있었다. 이는 드레인 전압 바이어스 하에서의 낮은 채널 캐리어 농도는 적은 defect state를 만들기 때문으로 짧은 채널 길이의 TFT가 긴 채널 길이의 TFT보다 $V_{TH}$ 열화가 적었다. 이러한 결과는 짧은 채널 길이의 nc-Si TFT가 디스플레이 분야에 있어 다양하게 응용될 것으로 기대된다.

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Study on the Stability of Organic Thin-Film Transistors Fabricated by Inserting a Polymeric Film as an Adhesion Layer

  • Hyung, Gun-Woo;Park, Il-Houng;Seo, Ji-Hoon;Seo, Ji-Hyun;Choi, Hak-Bum;Kim, Young-Kwan
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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    • pp.1348-1351
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    • 2007
  • We demonstrated that the threshold voltage shift owing to a gate-bias stress is originated from the trapped charges at the interface between semiconductor layer and dielectric layer, and such drawback can be settled by applying long-term delay time to the gate electrode.

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Frequency Dependence of OLED Voltage Shift Degradation

  • Kim, Hyun-Jong;Kim, Su-Hwan;Chang, Seung-Wook;Lee, Dong-Kyu;Jeong, Dong-Seob;Chung, Ho-Kyoon;Hong, Yong-Taek
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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    • pp.1108-1111
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    • 2007
  • OLED driving voltage shift can reduce the OLED display lifetime, especially for digitally driven AMOLED. By operating OLED at high frequency, we were able to suppress OLED voltage shift degradation, expecting improved AMOLED lifetime. We describe frequency dependence of voltage shift obtained from bias stress test of OLED.

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A novel integrated a-Si:H gate driver

  • Lee, Jung-Woo;Hong, Hyun-Seok;Lee, Eung-Sang;Lee, Jung-Young;Yi, Jun-Shin;Bae, Byung-Seong
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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    • pp.1176-1178
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    • 2007
  • A novel integrated a-Si:H gate driver with high reliability has been designed and simulated. Since the a-Si:H TFT is easily degraded by gate bias stress, we should optimize the circuit considering the threshold voltage shift. The conventional circuit shows voltage drop at the input stage by threshold voltage of the TFT, however, the proposed circuit dose not shows voltage drop and keeps constant regardless of threshold voltage shift of the TFT.

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GaAs MESFET의 온도변화에 다른 게이트 누설전류 특성 (Gate Leakage Current Characteristics of GaAs MESFETS′ with different Temperature)

  • 원창섭;김시한;안형근;한득영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.50-53
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    • 2001
  • In this study, gate leakage current mechanism has been analyzed for GaAs MESFET with different temperatures ranging from 27$^{\circ}C$ to 300$^{\circ}C$ . It is expected that the thermionic and field emission at the MS contact will dominate the current flow. Thermal cycle is applied to test the reliability of the device. From the results, it is proved that thermal stress gradually increases the gate leakage current at the same bias conditions and leads to the breakdown and failure mechanism which is critical in the field equipment. Finally the gate contact under the repeated thermal shock has been tested to check the quality of Schottky barrier and the current will be expressed in the analytical from to associate with the electrical characteristics of the device.

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