• Title/Summary/Keyword: Threshold Effect

Search Result 1,513, Processing Time 0.023 seconds

Relation of Threshold Voltage and Scaling Theory for Double Gate MOSFET (DGMOSFET의 문턱전압과 스켈링 이론의 관계)

  • Jung, Hak-Kee
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.16 no.5
    • /
    • pp.982-988
    • /
    • 2012
  • This paper has presented the relation of scaling theory and threshold voltage of double gate(DG) MOSFET. In the case of conventional MOSFET, current and switching frequency have been analyzed based on scaling theory. To observe the possibility of application of scaling theory for threshold voltage of DGMOSFET, the change of threshold voltage has been observed and analyzed according to scaling theory. The analytical potential distribution of Poisson equation has been used, and this model has been already verified. To solve Poisson equation, charge distribution such as Gaussian function has been used. As a result, it has been observed that threshold voltage is grealty changed according to scaling factor and change rate of threshold voltages is traced for scaling of doping concentration in channel. This paper has explained for the best modified scaling theory reflected the influence of two gates as using weighting factor when scaling theory has been applied for channel length and channel thickness.

Estimation of Genetic Parameters for Calving Ease by Heifers and Cows Using Multi-trait Threshold Animal Models with Bayesian Approach

  • Lee, D.H.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.15 no.8
    • /
    • pp.1085-1090
    • /
    • 2002
  • Genetic parameters for birth weights (BWT), calving ease scores observed from calves born by heifers (CEH), and calving ease scores observed from calves born by cows (CEC) were estimated using Bayesian methodology with Gibbs sampling in different threshold animal models. Data consisted of 77,458 records for calving ease scores and birth weights in Gelbvieh cattle. Gibbs samplers were used to obtain the parameters of interest for the categorical traits in two univariate threshold animal models, a bivariate threshold animal model, and a three-trait linear-threshold animal model. Samples of heritabilities and genetic correlations were calculated from the posterior means of dispersion parameters. In a univariate threshold animal model with CEH (model 1), the posterior means of heritabilities for calving ease was 0.35 for direct genetic effects and 0.18 for maternal genetic effects. In the other univariate threshold model with CEC (model 2), the posterior means of heritabilities of CEC was 0.28 for direct genetic effects and 0.18 for maternal genetic effects. In a bivariate threshold model with CEH and CEC (model 3), heritability estimates were similar to those in unvariate threshold models. In this model, genetic correlation between heifer calving ease and cow calving ease was 0.89 and 0.87 for direct genetic effect and maternal genetic effects, respectively. In a three-trait animal model, which contained two categorical traits (CEH and CEC) and one continuous trait (BWT) (model 4), heritability estimates of CEH and CEC for direct (maternal) genetic effects were 0.40 (0.23) and 0.23 (0.13), respectively. In this model, genetic correlation estimates between CEH and CEC were 0.89 and 0.66 for direct genetic effects and maternal effects, respectively. These estimates were greater than estimates between BWT and CEH (0.82 and 0.34) or BWT and CEC (0.85 and 0.26). This result indicates that CEH and CEC should be high correlated rather than estimates between calving ease and birth weight. Genetic correlation estimates between direct genetic effects and maternal effects were -0.29, -0.31 and 0.15 for BWT, CEH and CEC, respectively. Correlation for permanent environmental effects between BWT and CEC was -0.83 in model 4. This study can provide genetic evaluation for calving ease with other continuous traits jointly with assuming that calving ease from first calving was a same trait to calving ease from later parities calving. Further researches for reliability of dispersion parameters would be needed even if the more correlated traits would be concerned in the model, the higher reliability could be obtained, especially on threshold model with property that categorical traits have little information.

The Pressure Pain Threshold's Comparison Following Time Progress After IMS to the Trigger Point (동통 유발점에 대한 Intramuscular Stimulation(IMS) 후 시간 경과에 따른 압통 역치에 대한 비교)

  • Hong, Soon-Il;Lee, Hae-Deok
    • Journal of Korean Physical Therapy Science
    • /
    • v.3 no.4
    • /
    • pp.181-187
    • /
    • 1996
  • The purpose of this study is to help understand the pressure pain threshold's comparison following time progress after IMS to the trigger point and recognize this methode' effect for treating these kind of myofascial pain syndrome in clinic. Resently, myofascial pain syndrome is a disease that keeps the highest rate of patients visiting the Department of Rehabilitation Medicine. and so one should understand the change of IMS'effect following time progress for patients to be dealt rightly in clinic. In addition, the theory and treatment of myofascial pain syndrome needs to be understood or to be dealt rightly for therapists to treat and to approach to the right moment in right mode for the patients with myofascial pain syndrome. Therefore, one should know where to stimulate and why one stimulate trigger point and what effect one obtain after IMS.

  • PDF

Cross-media Approaches to Risk Management of Environmental Pollution in Korea (한국에서의 환경오염에 의한 위해성관리의 종합적 접근방법)

  • Chong, Yong
    • Environmental Analysis Health and Toxicology
    • /
    • v.4 no.1_2
    • /
    • pp.55-65
    • /
    • 1989
  • Nevertheless the serious environmental pollution in Korea has been discussed in concern with health effect, the significant effect are not determined easily. Toxicological method has been used to establish safe levels of exposure for environmental pollutants to have threshold health effect below which significant effects are unlikely to occur. However the conventional method cannot to establish safe levels of exposure for non-threshold pollutants have been used to express comprehensive pollution degree, not in detailed toxic effects. Acceptable exposure or risk levels are decides by policymakers who consider descriptions and estimates of risks together with social and economic benefits. This paper focuses on the concept development of risk assessment and describes some risks of environmental pollution based on the surveyed date in Korea. The current concepts of risk assessment in policy descisions can be explored and areas for possible improvement, given current scientific knowledge are identified. The experience of foreign countries can provide a realistic basis for evaluating the existing data of environmental pollutants. To improve the environmental quality, risk regulation should be managed as soon as possible in Korea.

  • PDF

Surface Treatment Effect on Electrical Characteristics of Ink-Jet Printed Pentacene OTFTs Employing Suspended Source/Drain Electrode

  • Park, Young-Hwan;Kim, Yong-Hoon;Kang, Jung-Won;Oh, Myung-Hwan;Han, Jeong-In
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2007.08b
    • /
    • pp.1312-1314
    • /
    • 2007
  • The effect of gate insulator surface treatment on electrical characteristics of bottom contact (BC) and suspended source/drain (SSD) organic thinfilm transistors (OTFTs) was studied. Triisopropylsilylethynyl pentacene was used as an active material and was printed by ink-jet printing method. In case of the BC OTFTs, threshold voltage was shifted from positive to near zero, and the fieldeffect mobility was increased when the gate insulator surface was treated with hexamethyldisilazane. However, in case of SSD OTFT, threshold voltage shift was not observed and the field-effect mobility was decreased.

  • PDF

Investigation of Solvent Effect on the Electrical Properties of TIPS Pentacene Organic Thin-film Transistors

  • Kim, Kyung-Seok;Chung, Kwan-Soo;Kim, Yong-Hoon;Han, Jeong-In
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2006.08a
    • /
    • pp.1150-1153
    • /
    • 2006
  • In this paper, we investigated the effect of solvent on electrical properties of triisopropylsilyl (TIPS) pentacene organic thin-film transistors (OTFTs). The TIPS pentacene was spin coated by using chlorobenzene, p-xylene, chloroform and toluene as solvent. Fabricated OTFT with chlorobenzene showed field-effect mobility of $0.01\;cm^2/V{\cdot}s$, on/off ratio $4.3{\times}10^3$ and threshold voltage of 5.5 V. In contrast, with chloroform the mobility was $5.8{\times}10^{-7}\;cm^2/Vs$, on/off ratio $1.1{\times}10^2$ and threshold voltage of 1.7 V.

  • PDF

A New Semi-Empirical Model for the Backgating Effect on the Depletion Width Modulation in GaAs MESFET's

  • Murty, Neti V.L. Narasimha;Jit, S.
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.8 no.1
    • /
    • pp.104-109
    • /
    • 2008
  • A simple and efficient way of modeling backgating in GaAs MESFET's is presented through depletion width modulation of Schottky junction and channel-substrate interface. It is shown semi-empirically that such a modulation of depletion widths causes serious troubles in designing precision circuits since backgating drastically reduces threshold voltage of MESFET as well as drain current. Finally, some of the results are compared with reported experimental results. This model may serve as a starting point for rigorous characterization of backgating effect on various device parameters of GaAs MESFET's.

Enhancement of Pulsed-Laser Ablation by Phase Explosion of Liquid (액체의 상폭발 과정에 의한 펄스 레이저 용발률의 증진)

  • Kim, Dong-Sik;Lee, Ho
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.25 no.11
    • /
    • pp.1483-1491
    • /
    • 2001
  • Enhancement of pulsed-laser ablation by an artificially deposited liquid film is presented. Measurements of ablation rate, ablation threshold, and surface topography arc performed. Correlation between material ablation and photoacoustic effect is examined by the optical beam deflection method. The dependence of ablation rate on liquid-film thickness and chemical composition is also examined. The results indicate that photomechanical effect in the phase explosion of liquid is responsible for the enhanced ablation. The low critical temperature of liquid induces explosive vaporization with localized photoacoustic excitation in the superheat limit and increases the ablation efficiency. Experiments were carried out utilizing a Q-swiched Nd:YAG laser at near-threshold laser fluences with negligible plasma effect (up to ∼100 MW/cm$^2$).

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

  • Yoon, Min-Young;Cho, Nam-Geun;Hwang, Woo-Jun;Jang, Chul-Ho
    • Journal of Acupuncture Research
    • /
    • v.19 no.2
    • /
    • pp.105-113
    • /
    • 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.

  • PDF

Effect of Post Annealing in Oxygen Ambient on the Characteristics of Indium Gallium Zinc Oxide Thin Film Transistors

  • Jeong, Seok Won
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.27 no.10
    • /
    • pp.648-652
    • /
    • 2014
  • We have investigated the effect of electrical properties of amorphous InGaZnO thin film transistors (a-IGZO TFTs) by post thermal annealing in $O_2$ ambient. The post-annealed in $O_2$ ambient a-IGZOTFT is found to be more stable to be used for oxide-based TFT devices, and has better performance, such as the on/off current ratios, sub-threshold voltage gate swing, and, as well as reasonable threshold voltage, than others do. The interface trap density is controlled to achieve the optimum value of TFT transfer and output characteristics. The device performance is significantly affected by adjusting the annealing condition. This effect is closely related with the modulation annealing method by reducing the localized trapping carriers and defect centers at the interface or in the channel layer.