• Title/Summary/Keyword: threshold effect

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The Effects of Low Level Laser Therapy on Current Perception in Trigeminal Neuralgia Patients (삼차신경통 환자에서 저출력레이저 조사에 따른 전류인지역치의 변화효과)

  • Heo, Jun-Young;Tae, Il-Ho;Ko, Myung-Yun;Ahn, Yong-Woo
    • Journal of Oral Medicine and Pain
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    • v.33 no.1
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    • pp.97-103
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    • 2008
  • The purpose of this study was to examine the effect of LLLT on current perception threshold in trigeminal neuralgia patients. Affected site and non-affected site was irradiated by GaAlAs diode laser. Current perception threshold was evaluated with $Neurometer^{(R)}$ CPT/C before and after LLLT. As an outcomes,CPT were obtained. We made a comparision of these values and the results were as follows. 1. There were no significant difference in CPT between affected site and non-affected site before and after LLLT irradiation. 2. There were no significant difference in CPT between affected site and non-affected site after LLLT irradiation. 3. But, CPT values of $A{\beta}$ fiber incresed slightly on both site after LLLT irradiation

Effects of Acupuncture-Like Transcutaneous Electrical Nerve Stimulation and Silver Spike Point Therapy on Pressure Pain Sensitivity (침형 경피신경 전기자극과 은침 전기자극 치료가 압통 역치에 미치는 효과)

  • Kim, Yuh-Jin;Lee, Eun-Joo;Cho, Ji-Sook;Yi, Chung-Hwi
    • Physical Therapy Korea
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    • v.2 no.2
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    • pp.66-72
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    • 1995
  • The purpose of this study was to determine a more effective method for shoulder pain reduction. Forty-five normal subjects were randomly assigned to one of 3 groups a control group, an acupuncture-like transcutaneous electrical nerve stimulation(ALTENS) group, and a silver spike point(SSP) group. Each person in the ALTENS and SSP groups was measured for pressure pain threshold before and after a 20 minute treatment. The control group was also checked for pressure pain threshold before and after a 20 minute period but no "treatment" was given. The major findings were as follows ; 1)The ALTENS and SSP groups showed significant differences before and after treatment but the control group showed no significant difference. 2)When the three groups were compared, the only significant difference was between the SSP group and the control group. As mentioned above, it may be concluded that both ALTENS and SSP therapy were effective in reducing shoulder pain when measured directly after treatment. However, SSP did not show any superior effect. Further study should be done to determine the effective the maintained pain reduction with post-treatment time lapse.

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Fabrication and Electrical Properties of Local Damascene FinFET Cell Array in Sub-60nm Feature Sized DRAM

  • Kim, Yong-Sung;Shin, Soo-Ho;Han, Sung-Hee;Yang, Seung-Chul;Sung, Joon-Ho;Lee, Dong-Jun;Lee, Jin-Woo;Chung, Tae-Young
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.6 no.2
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    • pp.61-67
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    • 2006
  • We fabricate local damascene FinFET cell array in sub-60nm feature sized DRAM. The local damascene structure can remove passing-gate-effects in FinFET cell array. p+ boron in-situ doped polysilicon is chosen for the gate material, and we obtain a uniform distribution of threshold voltages at around 0.7V. Sub-threshold swing of 75mV/d and extrapolated off-state leakage current of 0.03fA are obtained, which are much suppressed values against those of recessed channel array transistors. We also obtain a few times higher on-state current. Based on the improved on- and off-state current characteristics, we expect that the FinFET cell array could be a new mainstream structure in sub-60nm DRAM devices, satisfying high density, low power, and high-speed device requirements.

Deformational Characteristics of Cohesive Soils Using Resonant Column / Torsional Shear Testing Equipment (공진주/비틂 전단(RC/TS)시험기를 이용한 점성토의 변형특성)

  • 김동수
    • Geotechnical Engineering
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    • v.11 no.1
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    • pp.113-126
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    • 1995
  • Both resonant column (RC) and torsional shear(TS) tests were performed at small to intermediate strain levels to investigate deformational characteristics of cohesive soils. The effects of variables such as strain amplitude, loading frequency, and number of loading cycles were studied. Plasticity index was found to be an important variables in evaluating these effects. Soils tested include undisturbed silts and clays and compacted subgrade soils. At small strains below the elastic threshold, shear modulus is independent of number of loading cycles and strain amplitude. Small strain material damping exists wi th ranges be tween 1.1% and 1.7% for 75 tests. The elastic threshold strain increases as confining pressure and plasticity index increases. Above the cyclic threshold strain, the modulus of cohesive soil decreases with increasing number of cycles while damping ratio is almost independent of number of load cycles. Moduli and damping ratios of cohesive soils obtanined by RC test are higher than those from 75 test because of the frequency effect. Shear modulus of cohesive soil increases linearly as a function of the logarithm of loading frequency.

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Self-healing capacity of damaged rock salt with different initial damage

  • Chen, Jie;Kang, Yanfei;Liu, Wei;Fan, Jinyang;Jiang, Deyi;Chemenda, Alexandre
    • Geomechanics and Engineering
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    • v.15 no.1
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    • pp.615-620
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    • 2018
  • In order to analyze the healing effectiveness of rock salt cracks affected by the applied stresses and time, we used the ultrasonic technology to monitor the ultrasonic pulse velocity (UPV) variations for different initial stress-damaged rock salts during self-healing experiments. The self-healing experiments were to create different conditions to improve the microcracks closure or recrystallized, which the self-healing effect of damaged salt specimens were analyzed during the recovery period about 30 days. We found that: The ultrasonic pulse velocity of the damaged rock salts increases rapidly during the first 9 days recovery, and the values gradually increase to reach constant values after 30 days. The damaged value and the healed value were identified based on the variation of the wave velocity. The damaged values of the specimens that are subject to higher initial damage stress are still keeping in large after 30 days recovery under the same recovery condition It is interesting that the damage and the healing were not in the linear relationship, and there also existed a damage threshold for salt cracks healing ability. When the damage degree is less than the threshold, the self-healing ratio of rock salt is increased with the increase in damage degree. However, while the damage degree exceeds the threshold, the self-healing ratio is decreased with the increase in damage.

Effects of Pre-eccentric Exercise on Exercise Induced Muscle Damage (사전 원심성 운동이 운동 유발 근 손상에 미치는 효과)

  • Kim, Byoung-Ju;Lim, Young-Eun;Yoon, Se-Won;Park, Seung-Kyu;Kim, Tae-Youl
    • The Journal of Korean Physical Therapy
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    • v.20 no.1
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    • pp.1-9
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    • 2008
  • Purpose: This study examined the effects of pre-eccentric exercise to the quadriceps for the prevention of delayed onset muscle soreness (DOMS) and recovery of muscular function, depending on the training intensities. Methods: Subjects were divided into one of three groups that control group, a low intensity eccentric exercise group (LIEE group) and a high intensity eccentric exercise group (HIEE group). Subjects who underwent pre-eccentric exercise undertook exercise at an intensity of 25% and 75% of maximal voluntary contractions, respectively. After undertaking pre-eccentric exercise for eight weeks, eccentric exercise was applied again to induce DOMS. Measurements were conducted to examine pain and muscular function changes before, immediately after, after the induction of DOMS, and at the first, third, fifth and seventh days after the induction of DOMS. Results: Subjects who underwent pre-eccentric exercise showed a significant difference from the control group for the changes in the visual analogue scale (VAS) pain threshold, pressure pain threshold and muscle thickness by isometric contraction from measuring DOMS, and in particular, pain threshold by isometric contraction had remarkable effect in the LIEE group of subjects. For the change of the root mean square values using mechanomyography (MMG) as the measurement of muscular function recovery, subjects who had undertaken pre-eccentric exercise group showed a significant difference as compared to the control group. Conclusion: Pre-eccentric exercise was very effective in preventing and recovering delayed onset muscle soreness and was helpful to prevent and recover from decreased muscular function. The difference based on the intensity of exercise was not great, but it was more effective in the low intensity eccentric exercise group of subjects. Therefore, it can be considered that pre-eccentric exercise has a high application value as a physical therapy intervention for prevention and rehabilitation of sports injuries.

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Tests for the Structure Change and Asymmetry of Price Volatility in Farming Olive Flounder (양식 넙치가격 변동성의 구조변화와 비대칭성 검증)

  • Kang, Seok-Kyu
    • The Journal of Fisheries Business Administration
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    • v.45 no.2
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    • pp.29-38
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    • 2014
  • This study is to analyse the timing of the structural change of price volatility and the asymmetry of price volatility during the period before and after the timing of the structural change of price volatility using Jeju Farming Olive Flounder's production area market price data from January 1, 2007 to June 30, 2013. The analysis methods of Quandt-Andrews break point test and Threshold GARCH model are employed. The empirical results of this study are summarized as follows: First, the result of Quandt-Andrews break point test shows that a single structural change in price volatility occurred on May 4, 2010 over the sample period. Second, during the period before structural change, daily price change rate has averagely positive value which means price increase, but during the period after structural change daily price change rate has averagely negative value which means price decrease. Also, daily volatility of price change rate during the period before structural change is higher than during the period after structural change. This indicates that price volatility decreases after structural change. Third, the estimation results of Threshold GARCH Model show that the volatility response against price increase is larger during the period after structural change than during the period before structural change. Also the result shows the volatility response against price decrease is larger during the period after structural change than during the period before structural change. And, irrespective of the timing of structural change, price increase has an larger effect on volatility than price decrease. This means volatility is asymmetric at price increase.

Temperature Reliability Analysis based on SiC UMOSFET Structure (SiC UMOSFET 구조에 따른 온도 신뢰성 분석)

  • Lee, Jeongyeon;Kim, Kwang-Soo
    • Journal of IKEEE
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    • v.24 no.1
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    • pp.284-292
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    • 2020
  • SiC-based devices perform well in high-voltage environments of more than 1200V compared to silicon devices, and are particularly stable at very high temperatures. Therefore, 1700V UMOSFET has been actively researched and developed for the use of electric power systems such as electric vehicles and aircrafts. In this paper, we analysed thermal variations of critical variables (breakdown voltage (BV), on-resistance (Ron), threshold voltage (vth), and transconductance (gm)) for the three type 1700V UMOSFETs-Conventional UMOSFET (C-UMOSFET), Source Trench UMOSFET (ST-UMOSFET), and Local Floating Superjunction UMOSFET (LFS-UMOSFET). All three devices showed BV increase, Ron increase, vth decrease, and gm decrease with increasing temperature. However, there are differences in BV, Ron, vth, gm according to the structural differences of the three devices, and the degree and cause of the analysis were compared. All results were simulated using sentaurus TCAD.

Extreme value modeling of structural load effects with non-identical distribution using clustering

  • Zhou, Junyong;Ruan, Xin;Shi, Xuefei;Pan, Chudong
    • Structural Engineering and Mechanics
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    • v.74 no.1
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    • pp.55-67
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    • 2020
  • The common practice to predict the characteristic structural load effects (LEs) in long reference periods is to employ the extreme value theory (EVT) for building limit distributions. However, most applications ignore that LEs are driven by multiple loading events and thus do not have the identical distribution, a prerequisite for EVT. In this study, we propose the composite extreme value modeling approach using clustering to (a) cluster initial blended samples into finite identical distributed subsamples using the finite mixture model, expectation-maximization algorithm, and the Akaike information criterion; (b) combine limit distributions of subsamples into a composite prediction equation using the generalized Pareto distribution based on a joint threshold. The proposed approach was validated both through numerical examples with known solutions and engineering applications of bridge traffic LEs on a long-span bridge. The results indicate that a joint threshold largely benefits the composite extreme value modeling, many appropriate tail approaching models can be used, and the equation form is simply the sum of the weighted models. In numerical examples, the proposed approach using clustering generated accurate extrema prediction of any reference period compared with the known solutions, whereas the common practice of employing EVT without clustering on the mixture data showed large deviations. Real-world bridge traffic LEs are driven by multi-events and present multipeak distributions, and the proposed approach is more capable of capturing the tendency of tailed LEs than the conventional approach. The proposed approach is expected to have wide applications to general problems such as samples that are driven by multiple events and that do not have the identical distribution.

Comparison of Topographical Parameter for DTED and Grid DEM from 1:50,000 Digital Map (DTED와 1:50,000 수치지형도에 의한 격자 DEM의 지형 매개변수 비교)

  • Kim, Yeon-Jun;Shin, Ke-Jong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.5 no.3
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    • pp.19-32
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    • 2002
  • Topographic information is indispensable in the applications that require elevational data. These applications are exemplified by watershed partition, extraction of drainage networks, viewshed analysis, derivation of geomorphologic features, quantification of landslide-terrain, and identification of topographic settings susceptible to landsliding. Therefore, we study the accuracy of data on topographic parameters derived from digital elevation models(DEMs). This research wished to analyze the effect that data source and grid size get in topography parameter using gridded DEM. An analysis of topography parameter extract and compared drainage basin, watershed slope, stream network using DEM is constructed by digital map and DTED DEM. Especially, when extract stream network from gridded DEM, received much effects according to threshold value of flowaccumulation regardless of DEM grid size. Therefore, this study applied equal threshold value of flowaccumulation for two data sources, and compare and analyzed stream network.

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