• Title/Summary/Keyword: sub-threshold

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Combined effects of food and exercise on anaphylaxis

  • Kim, Cheol Woo;Figueroa, Arturo;Park, Chan Ho;Kwak, Yi Sub;Kim, Kwi Baek;Seo, Dae Yun;Lee, Hyung Rock
    • Nutrition Research and Practice
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    • v.7 no.5
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    • pp.347-351
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    • 2013
  • Food-dependent exercise-induced anaphylaxis (FDEIAn) is induced by different types and various intensities of physical activity, and is distinct from food allergies. It has been shown that consumption of allergenic food followed by exercise causes FDEIAn symptoms. Intake of allergenic food or medication before exercise is a major predisposing factor for FDEIAn. Urticaria and severe allergic reactions are general symptoms of FDEIAn. Dermatological tests and serum IgE assays are the typical prescreening methods, and have been used for several decades. However, these screening tests are not sufficient for detecting or preventing FDEIAn. It has been found that exercise may stimulate the release of mediators from IgE-dependent mast cells that can result in FDEIAn when a certain threshold level has been exceeded. Mast cell degradation might be a major factor to induce FDEIAn but this has not been determined. A number of foods have been reported to be involved in the onset of FDEIAn including wheat, eggs, chicken, shrimp, shellfish, nuts, fruits, and vegetables. It is also known that aspirin increases the occurrence of type I allergy symptoms when combined with specific foods. Moreover, high intensity and frequent exercise are more likely to provoke an attack than low intensity and less frequent exercise. In this paper, we present the current views of the pathophysiological mechanisms underlying FDEIAn within the context of exercise immunology. We also present a detailed FDEIAn definition along with etiologic factors and medical treatment for cholinergic urticaria (UC) and exercise-induced anaphylaxis (EIA).

$TiO_2$ 채널 기반 산화물 트랜지스터

  • Choe, Gwang-Hyeok;Kim, Han-Gi
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2011.05a
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    • pp.60.2-60.2
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    • 2011
  • 본 연구에서는 Indium-free 및 gallium-free 기반의 산화물 TFT를 제작하기 위해 n-type $TiO_2$ 반도체 기반의 thin film transistor ($Mo/TiO_{2-x}/SiO_2/p+\;+Si$)를 oxygen deficient black $TiO_{2-x}$ 타겟을 이용하여 DC magnetron sputtering 공법으로 제작하고 그 특성을 분석하였다. DC magnetron sputtering 공법으로 성막된 $TiO_{2-x}$ semiconductor의 전기적, 광학적, 화학적 결합 에너지 및 구조적 특성 분석을 위해 semiconductor parameter analyzer (Aglient 4156-C), UV/Vis spectrometer, X-ray Photoelectron Spectroscopy, Transmission Electron Microscopy를 각각 이용하여 분석하였으며 이를 RTA 전/후 특성 비교를 통하여 관찰하였다. $TiO_{2-x}$ TFT의 소자 특성은 RTA 열처리 전/후 전형적인 insulator 특성에서 semiconductor 특성으로 변화되는 것을 관찰할 수 있었으며, 최적화된 열처리 공정에서 filed effect mobility 0.69 $cm^2$/Vs, on to off current ratio $2.04{\times}10^7$, sub-threshold swing 2.45 V/decade와 Vth 10.45 V를 확보할 수 있었다. 또한 RTA 열처리 후 밴드갭이 3.25에서 3.41로 확장되는 특성을 나타내었다. 특히 RTA 열처리 후 stoichiometric $TiO_2$ 상태와는 다른 $Ti^{2+}$, $Ti^{3+}$, $Ti^{4+}$ 등의 다양한 oxidation states가 관찰되었으며 이러한 oxidation states를 $TiO_{2-x}$ 박막에서의 oxygen deficient 상태와 연관시킴으로써 oxygen vacancy의 n-type dopant로의 거동을 확인하였다. $TiO_2$ 채널 기반의 TFT 특성을 통하여서 indium free 또는 gallium free 산화물 채널로써의 가능성을 확인하였다.

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Quantum-Mechanical Modeling and Simulation of Center-Channel Double-Gate MOSFET (중앙-채널 이중게이트 MOSFET의 양자역학적 모델링 및 시뮬레이션 연구)

  • Kim, Ki-Dong;Won, Tae-Young
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.7 s.337
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    • pp.5-12
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    • 2005
  • The device performance of nano-scale center-channel (CC) double-gate (DG) MOSFET structure was investigated by numerically solving coupled Schr$\"{o}$dinger-Poisson and current continuity equations in a self-consistent manner. The CC operation and corresponding enhancement of current drive and transconductance of CC-NMOS are confirmed by comparing with the results of DG-NMOS which are performed under the condition of 10-80 nm gate length. Device optimization was theoretically performed in order to minimize the short-channel effects in terms of subthreshold swing, threshold voltage roll-off, and drain-induced barrier lowering. The simulation results indicate that DG-MOSFET structure including CC-NMOS is a promising candidates and quantum-mechanical modeling and simulation calculating the coupled Schr$\"{o}$dinger-Poisson and current continuity equations self-consistently are necessary for the application to sub-40 nm MOSFET technology.

Hydrogen-Related Gate Oxide Degradation Investigated by High-Pressure Deuterium Annealing (고압 중수소 열처리 효과에 의해 조사된 수소 결합 관련 박막 게이트 산화막의 열화)

  • 이재성
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.41 no.11
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    • pp.7-13
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    • 2004
  • Experimental results are presented for the degradation of 3 nm-thick gate oxide under -2.5V $\leq$ V$_{g}$ $\leq$-4.0V stress and 10$0^{\circ}C$ conditions using P and NMOSFETs that are annealed with hydrogen or deuterium gas at high-pressure (5 atm). The degradation mechanisms are highly dependent on stress conditions. For low gate voltage, hole-trapping is found to dominate the reliability of gate oxide both in P and NMOSFETs. With increasing gate voltage to V$_{g}$ =-4.0V, the degradation becomes dominated by electron-trapping in NMOSFETs, however, the generation rate of "hot" hole was very low, because most of tunneling electrons experienced the phonon scattering before impact ionization at the Si interface. Statistical parameter variations as well as the gate leakage current depend on and are improved by high-pressure deuterium annealing, compared to corresponding hydrogen annealing. We therefore suggest that deuterium is effective in suppressing the generation of traps within the gate oxide. Our results therefore prove that hydrogen related processes are at the origin of the investigated oxide degradation.gradation.

Effects of Electroacupuncture and Manual-acupuncture at Combined Acupoints on Sex and Age in Rats (침(鍼)과 전침(電鍼) 자극 시 백서(白鼠)의 성별(性別)과 주령(週齡) 및 경혈배합(經穴配合)이 소장(小腸) 수송능(輸送能)에 미치는 영향)

  • Yun, Jeong-Ahn;Yu, Yun-Cho;Cho, Nam-Kun;Son, In-Chul;Lee, Ho-Sub;Lee, June-Mu;Kim, Kyung-Sik
    • Journal of Acupuncture Research
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    • v.24 no.1
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    • pp.179-193
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    • 2007
  • Objectives: It has been demonstrated that acupuncture treats diseases while that the widespread use of that clinically and experimentally. It also has shown that electro-acupuncture(EA) is more effective than manual-acupuncture (MA). The purpose of this study was to investigate effect of EA and MA at combined acupoints on sex and age in rats. Methods: This study measured the effects of acupuncture treatment on small intestinal motility in rats. MA and EA(intensity, 5 times muscle twitch threshold) was applied for 30 minutes to the combined left and right sides acupoints on ST36, ST37, ST39 under enflurane anesthesia. EA and MA applied to the ST36, ST37, ST39 acupoints produced an elevation of small intestinal motility. Results: In experimental groups of combined left and right sides acupoints, only specified groups show elevation of small intestinal motility in male rats, 5 weeks age. Furthermore, combined left and right sides acupoints in EA and MA show differences effects according to the sex, male and female, and the age as 5, 6, 7, 8 weeks. Conclusion : Although these different according to the sex and age in rats do not have a established tendency, the present study suggest that effect of EA and MA are experimentally dependent upon the sex and age on small intestinal motility in rats.

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A study of Recess Channel Array Transistor with asymmetry channel for high performance and low voltage Mobile 90nm DRAMs (고성능 저전압 모바일향 90nm DRAM을 위한 비대칭 채널구조를 갖는 Recess Channel Array Transistor의 제작 및 특성)

  • Kim, S.B.;Lee, J.W.;Park, Y.K.;Shin, S.H.;Lee, E.C.;Lee, D.J.;Bae, D.I.;Lee, S.H.;Roh, B.H.;Chung, T.Y.;Kim, G.H.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.163-166
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    • 2004
  • 모바일향 90nm DRAM을 개발하기 위하여 비대칭 채널 구조를 갖는 Recess Channel Array Transistor (RCAT)로 cell transistor를 구현하였다. DRAM cell transistor에서 junction leakage current 증가는 DRAM retention time 열화에 심각한 영향을 미치는 요인으로 알려져 있으며, DRAM의 minimum feature size가 점점 감소함에 따라 short channel effect의 영향으로 junction leakage current는 더욱 더 증가하게 된다. 본 실험에서는 short channel effect의 영향에 의한 junction leakage current를 감소시키기 위하여 Recess Channel Array Transistor를 도입하였고, cell transistor의 채널 영역을 비대칭으로 형성하여 data retention time을 증가시켰다. 비대칭 채널 구조을 이용하여 Recess Channel Array Transistor를 구현한 결과, sub-threshold 특성과 문턱전압, Body effect, 그리고, GIDL 특성에는 큰 유의차가 보이지 않았고, I-V특성인 드레인 포화전류(IDS)는 대칭 채널 구조인 transistor 대비 24.8% 정도 증가하였다. 그리고, data retention time은 2배 정도 증가하였다. 본 실험에서 얻은 결과는 향후 저전압 DRAM 개발과 응용에 상당한 기여를 할 것으로 기대된다.

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Interface Treatment Effect of High Performance Flexible Organic Thin Film Transistor (OTFT) Using PVP Gate Dielectric in Low Temperature (저온 공정 PVP게이트 절연체를 이용한 고성능 플렉서블 유기박막 트랜지스터의 계면처리 효과)

  • Yun, Ho-Jin;Baek, Kyu-Ha;Shin, Hong-Sik;Lee, Ga-Won;Lee, Hi-Deok;Do, Lee-Mi
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.24 no.1
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    • pp.12-16
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    • 2011
  • In this study, we fabricated the flexible pentacene TFTs with the polymer gate dielectric and contact printing method by using the silver nano particle ink as a source/drain material on plastic substrate. In this experiment, to lower the cross-linking temperature of the PVP gate dielectric, UV-Ozone treatment has been used and the process temperature is lowered to $90^{\circ}C$ and the surface is optimized by various treatment to improve device characteristics. We tried various surface treatments; $O_2$ Plasma, hexamethyl-disilazane (HMDS) and octadecyltrichlorosilane (OTS) treatment methods of gate dielectric/semiconductor interface, which reduces trap states such as -OH group and grain boundary in order to improve the OTFTs properties. The optimized OTFT shows the device performance with field effect mobility, on/off current ratio, and the sub-threshold slope were extracted as $0.63cm^2 V^{-1}s^{-1}$, $1.7{\times}10^{-6}$, and of 0.75 V/decade, respectively.

Face Authentication using Multi-radius LBP Matching of Individual Major Blocks in Mobile Environment (개인별 주요 블록의 다중 반경 LBP 매칭을 이용한 모바일 환경에서의 얼굴인증)

  • Lee, Jeong-Sub;Ahn, Hee-Seok;Keum, Ji-Soo;Kim, Tai-Hyung;Lee, Seung-Hyung;Lee, Hyon-Soo
    • Journal of Broadcast Engineering
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    • v.18 no.4
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    • pp.515-524
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    • 2013
  • In this paper, we propose a novel face authentication method based on LBP matching of individual major blocks in mobile environment. In order to construct individual major blocks from photos, we find the blocks that have the highest similarity and use different numbers of blocks depending on the probability distribution by applying threshold. And, we use multi-radius LBP histograms in the determination of individual major blocks to improve performance of generic LBP histogram based approach. By using the multi-radius LBP histograms in face authentication, we can successfully reduce the false acceptance rate compare to the previous methods. Also, we can see that the proposed method shows low error rate about 7.72% compare to the pervious method in spite of use small number of blocks about 44.59% only.

Super-Resolution Algorithm Using Motion Estimation for Moving Vehicles (움직임 추정 기법을 이용한 움직이는 차량의 초고해상도 복원 알고리즘)

  • Kim, Seung-Hoon;Cho, Sang-Bock
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.49 no.4
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    • pp.23-31
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    • 2012
  • This paper proposes a motion estimation-based super resolution algorithm to restore input low-resolution images of large movement into a super-resolution image. It is difficult to find the sub-pixel motion estimation in images of large movement compared to typical experimental images. Also, it has disadvantage which have high computational complexity to find reference images and candidate images using general motion estimation method. In order to solve these problems for the traditional two-dimensional motion estimation using the proposed registration threshold that satisfy the conditions based on the reference image is determined. Candidate image with minimum weight among the best candidates for super resolution images, the restoration process to proceed with to find a new image registration algorithm is proposed. According to experimental results, the average PSNR of the proposed algorithm is 31.89dB and this is better than PSNR of traditional super-resolution algorithm and it also shows improvement of computational complexity.

Spectrum Reuse Schemes with Power Control for Device-to-Device Communication in LTE-Advanced Cellular Network

  • Chhorn, Sok;Yoon, Seok-Ho;Seo, Si-O;Kim, Seung-Yeon;Cho, Choong-Ho
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.12
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    • pp.4819-4834
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    • 2015
  • The spectral efficiency of cellular networks can be improved when proximate users engage in device-to-device (D2D) communications to communicate directly without going through a base station. However, D2D communications that are not properly designed may generate interference with existing cellular networks. In this paper, we study resource allocation and power control to minimize the probability of an outage and maximize the overall network throughput. We investigate three power control-based schemes: the Partial Co-channel based Overlap Resource Power Control (PC.OVER), Fractional Frequency Reuse based Overlap Resource Power Control (FFR.OVER) and Fractional Frequency Reuse based Adaptive Power Control (FFR.APC) and also compare their performance. In PC.OVER, a certain portion of the total bandwidth is dedicated to the D2D. The FFR.OVER and FFR.APC schemes combine the FFR techniques and the power control mechanism. In FFR, the entire frequency band is partitioned into two parts, including a central and edge sub-bands. Macrocell users (mUEs) transmit using uniform power in the inner and outer regions of the cell, and in all three schemes, the D2D receivers (D2DRs) transmit with low power when more than one D2DRs share a resource block (RB) with the macrocells. For PC.OVER and FFR.OVER, the power of the D2DRs is reduced to its minimum, and for the FFR.APC scheme, the transmission power of the D2DRs is iteratively adjusted to satisfy the signal to interference ratio (SIR) threshold. The three schemes exhibit a significant improvement in the overall system capacity as well as in the probability of a user outage when compared to a conventional scheme.