• Title/Summary/Keyword: $V_T$

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The Evaluation and Countermeasures for the 2nd Arc Reduction for the High Speed Reclosing in 765kV Transmission Line (765kV 계통의 고속도 다상 재폐로 관련 2차 아크 검토 및 억제 방안)

  • Ahn, J.S.;Kim, J.Y.;Jin, J.Y.
    • Proceedings of the KIEE Conference
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    • 1995.07b
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    • pp.613-615
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    • 1995
  • KEPCO is now going on upgrading the highest system voltage from 345kV to 765kV since 1992. The main reason of this 765kV project is the bulk power transmission from the power generation sites at the East and West coasts to the Kyeong-in area. The first 765kV transmission lines will be constructed by 1998 and operated as 345kV level until 2001. This system needs a detailed evaluation of the 2nd arc in case of 765kV transmission line outages and the countermeasures for the fast arc reduction for the successful high speed reclosing. So, this paper deals with the simulation results of the 2nd arc characteristics using EMTP and comparison of Sh.R and HSGS for the reduction methods.

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Analysis of Insulator Failures Altar Installation of Arcing Horns in 154kV Transmission Lines (154kV 송전선로 Arcing Horn 적용에 따른 애자련 사고분석)

  • Cho, S.B.;Lee, H.K.
    • Proceedings of the KIEE Conference
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    • 1998.07e
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    • pp.1743-1745
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    • 1998
  • Insulators of 154kV T/L have been frequently damaged by fault currents. Arcing horn is a very effective and economic method for protection of insulators from the flashover. We developed arcing horns for 154kV T/L in order to protect insulators from the arc[1]. This paper analyzes the status of insulator failures in 154kV T/L after installation of the arcing horns.

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Effects of Cultivation Conditions on the Growth and Polyamine Composition in Methylobacterium extorquens AM1 Growing on Methanol (Methylobacterium extorquens AM1의 메탄올을 이용한 성장과 세포내 폴리아민 구성에 미치는 배양조건의 영향)

  • 엄치용;박기정;강빈구;김영민
    • Korean Journal of Microbiology
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    • v.29 no.6
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    • pp.387-391
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    • 1991
  • Methylobacterium extorquens AM1 growing on methanol as a sole source of carbon and energy was found to grow most rapidly (t$t_{d}$ =6h) at 30.deg.C in a mineral medium (pH 7.0) containing 0.5% (v/v) methanol which was agitated at 200 rpm (optimal cultivation condition). Cells grown under the optimal cultivation condition contained more spermidine, but less putrescine, than the cells grown on 2.5%(v/v) ( $t_{d}$ =8h ) or at 20.deg.C ( $t_{d}$ =8h ). Cells cultivated under the optimal condition was found to contain more spermidine than the cells grown at pH 6.0 (( $t_{d}$ =7h ) and pH 8.0 ($t_{d}$ =7.3h). the cells growing at the stationary phase under the optimal condition accumulated more spermine or putrescine than the cells growing at the same phase on 2.5%(v/v) methanol or at pH 6.0 and pH 8.0, respectively. M. extorquens AM1 grown in a medium agitated at 100 rpm ( $t_{d}$ =8.8h ) contained less spermidine and spermine than the cells grown under the optimal cultivation condition.

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MAX-MIN CONTROLLABILITY OF DELAY-DIFFERENTIAL GAMES IN HILBERT SPACES

  • Kang, Yong-Han;Jeong, Jin-Mun;Park, Jong-Yeoul
    • Journal of the Korean Mathematical Society
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    • v.38 no.1
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    • pp.177-191
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    • 2001
  • We consider a linear differential game described by the delay-differential equation in a Hilbert space H; (※Equations, See Full-text) U and V are Hilbert spaces, and B(t) and C(t) are families of bounded operators on U and V to H, respectively. A(sub)0 generates an analytic semigroup T(t) = e(sup)tA(sub)0 in H. The control variables g, and u and v are supposed to be restricted in the norm bounded sets (※Equations, See Full-text). For given x(sup)0 ∈ H and a given time t > 0, we study $\xi$-approximate controllability to determine x($.$) for a given g and v($.$) such that the corresponding solution x(t) satisfies ∥x(t) - x(sup)0∥ $\leq$ $\xi$($\xi$ > 0 : a given error).

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DOUBLE PAIRWISE (r, s)(u, v)-SEMICONTINUOUS MAPPINGS

  • Lee, Eun Pyo;Lee, Seung On
    • Journal of the Chungcheong Mathematical Society
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    • v.27 no.4
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    • pp.603-614
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    • 2014
  • We introduce the concepts of ($\mathcal{T}^{{\mu}{\gamma}}$, $\mathcal{U}^{{\mu}{\gamma}}$)-double (r, s) (u, v)-semiclosures and ($\mathcal{T}^{{\mu}{\gamma}}$, $\mathcal{U}^{{\mu}{\gamma}}$)-double (r, s)(u, v)-semiinteriors. Using the notions, we investigate some of characteristic properties of double pairwise (r, s)(u, v)-semicontinuous, double pairwise (r, s)(u, v)-semiopen and double pairwise (r, s)(u, v)-semiclosed mappings.

T.O.V.A. PROFILES OF CLINICALLY REFERRED CHILDREN WITH SYMPTOMS OF INATTENTION (주의산만을 주소로 소아정신과를 내원한 아동의 인지적 특성 - T.O.V.A. 양상을 중심으로 -)

  • Lee, Soo-Jin;Lee, Hye-Ran;Ko, Ryo-Won;Shin, Yee-Jin
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.11 no.2
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    • pp.290-296
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    • 2000
  • Objective:This study aims to investigate the cognitive characteristics of clinically referred children with symptoms of inattention, cach as having ADHD, tic disorder, and emotional disorder. Methods:65 boys(38 with ADHD, 17 with Tic disorder, and 10 with Emotional disorder) were individually assessed using the KEDI-WISC(FIQ, VIQ, PIQ) and T.O.V.A.(errors of omission, errors of commission, reaction time, variability, anticipatory response, multiple response), and the results of those tests were analyzed. Results:There was significant difference among three diagnostic groups of the VIQ of KEDIWISC and the reaction time of T.O.V.A. after the correction of the effect of age difference. Conclusion:The findings suggest that the reaction time of T.O.V.A. might be the useful variable to differentiate the ADHD from other psychiatric disorders and the effect of age and IQ difference should be considered carefully to diagnose in clinical setting.

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Psychophysiological Characteristics of Insomnia Patients Measured by Biofeedback System (바이오피드백을 이용하여 측정한 불면증 환자의 정신생리적 특징)

  • Huh, Sung-Young;Lee, Jin-Seong;Kim, Sung-Gon;Kim, Ji-Hoon;Jung, Woo-Young
    • Sleep Medicine and Psychophysiology
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    • v.22 no.2
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    • pp.70-76
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    • 2015
  • Background and Objectives: Insomnia is the most prevalent sleep disorder in the general population and is considered to be a disorder of hyperarousal. The aim of this study was to measure the psychophysiological responses in insomnia patients using a biofeedback system, and to compare them with results from normal healthy subjects. Materials and Methods: Eighty patients with primary insomnia (35 males and 45 females, average age $49.71{\pm}12.91years$) and 101 normal healthy controls (64 males and 37 females, average age $27.65{\pm}2.77$) participated in this study. Electromyography (EMG), heart rate (HR), skin conductance (SC), skin temperature (ST), and respiratory rate (RR) were recorded using a biofeedback system during 5 phases (baseline, stress 1, recovery 1, stress 2, recovery 2) of a stress reactivity test, and average values were calculated. Difference in values between the two groups in each corresponding phase was analyzed with independent t-test, and change in values across phases of the stress reactivity test was analyzed with paired t-test (all two-tailed, p<0.05). Results: Compared to normal controls, insomnia patients had higher EMG in all 5 phases (baseline : $7.72{\pm}3.88{\mu}V$ vs. $4.89{\pm}1.73{\mu}V$, t = -6.06, p<0.001 ; stress 1 : $10.29{\pm}5.16{\mu}V$ vs. $6.63{\pm}2.48{\mu}V$, t = -5.84, p<0.001 ; recovery 1 : $7.87{\pm}3.86{\mu}V$ vs. $5.17{\pm}2.17{\mu}V$, t = -5.61, p<0.001 ; stress 2 : $10.22{\pm}6.07{\mu}V$ vs. $6.98{\pm}2.98{\mu}V$, t = -4.37, p<0.001 ; recovery 2 : $7.88{\pm}4.25{\mu}V$ vs. $5.17{\pm}1.99{\mu}V$, t = -5.27, p<0.001). Change in heart rate across phases of the stress reactivity test were higher in normal controls than in insomnia patients (stress 1-baseline : $6.48{\pm}0.59$ vs. $3.77{\pm}0.59$, t = 3.22, p = 0.002 ; recovery 1- stress 1 : $-5.36{\pm}0.0.59$ vs. $-3.16{\pm}0.47$, t = 2.91, p = 0.004 ; stress 2-recovery 1 : $8.45{\pm}0.61$ vs. $4.03{\pm}0.47$, t = 5.72, p<0.001 ; recovery 2-stress 2 : $-8.56{\pm}0.65$ vs. $4.02{\pm}0.51$, t = -5.31, p<0.001). Conclusion: Psychophysiological profiles of insomnia patients in a stress reactivity test were different from those of normal healthy controls. These results suggest that the sympathetic nervous system is more highly activated in insomnia patients.

CONDITIONAL INTEGRAL TRANSFORMS AND CONVOLUTIONS OF BOUNDED FUNCTIONS ON AN ANALOGUE OF WIENER SPACE

  • Cho, Dong Hyun
    • Journal of the Chungcheong Mathematical Society
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    • v.26 no.2
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    • pp.323-342
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    • 2013
  • Let $C[0,t]$ denote the function space of all real-valued continuous paths on $[0,t]$. Define $Xn:C[0,t]{\rightarrow}\mathbb{R}^{n+1}$ and $X_{n+1}:C[0,t]{\rightarrow}\mathbb{R}^{n+2}$ by $X_n(x)=(x(t_0),x(t_1),{\cdots},x(t_n))$ and $X_{n+1}(x)=(x(t_0),x(t_1),{\cdots},x(t_n),x(t_{n+1}))$, where $0=t_0$ < $t_1$ < ${\cdots}$ < $t_n$ < $t_{n+1}=t$. In the present paper, using simple formulas for the conditional expectations with the conditioning functions $X_n$ and $X_{n+1}$, we evaluate the $L_p(1{\leq}p{\leq}{\infty})$-analytic conditional Fourier-Feynman transforms and the conditional convolution products of the functions which have the form $${\int}_{L_2[0,t]}{{\exp}\{i(v,x)\}d{\sigma}(v)}{{\int}_{\mathbb{R}^r}}\;{\exp}\{i{\sum_{j=1}^{r}z_j(v_j,x)\}dp(z_1,{\cdots},z_r)$$ for $x{\in}C[0,t]$, where $\{v_1,{\cdots},v_r\}$ is an orthonormal subset of $L_2[0,t]$ and ${\sigma}$ and ${\rho}$ are the complex Borel measures of bounded variations on $L_2[0,t]$ and $\mathbb{R}^r$, respectively. We then investigate the inverse transforms of the function with their relationships and finally prove that the analytic conditional Fourier-Feynman transforms of the conditional convolution products for the functions, can be expressed in terms of the products of the conditional Fourier-Feynman transforms of each function.

Clinical study on C.V.A patients in Hospital attached to college of oriental medicine and N.M.C. department oriental medicine (대학부속한방병원 및 국립의료원 한방진료부 뇌졸증환자에 대한 한방치료 현황 분석)

  • Shin, Hyun-Kyoo
    • Korean Journal of Oriental Medicine
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    • v.1 no.1
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    • pp.1-14
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    • 1995
  • The clinical study was carried out on 1737 cases of inpatient and outpatient which have been diagnosed as C.V.A at hospital attached to 8 colleges of oriental medicine in Korea or National Medical Center from January 1st 1994 to December 31st 1994. The results were as follows; 1. In this study, the case of Occlusive C.V.D was 70.1%, Cerebral hemorrhage was 20.5%, Transient ischemic attack (T.I.A) was 5.3%, Subdural hemorrhage was 3.0%, Subarachnoid hemorrhage was 0.8% 2. It was confirmed by C.T (20%), E.K.G. (19%), X-ray (19%), Urinalysis (19%), Hematoscopy (20%). 3. The mean days of hospital treatment was 27.88 days, mean days of ambulation was 70.34 days. The mean days of hospital treatment of Occlusive C.V.D, Cerebral hemorrhage, T.I.A., Subdural hemorrhage, Subarachnoid hemorrhage were 25.79, 39.32, 12.49, 16.23, 23.40 days, respectively. The mean days of ambulation of Occlusive C.V.D, Cerbral hemorrhage, T.I.A., Subdural hemorrhage, Subarachnoid hemorrhage were 74.40, 93.68, 69.10, 29.75, 32.57 days, respectavely. 4. Oriental medical treatment of C.V.A was mainly Acupuncture (25%), Paper of Chinese herbs (22%), Chinese physiotherapy (14%), Extract of Chinese herbs (11%). 5. Oriental medical physiotherapy for C.V.A was mostly E.S.T., Kinesiatrics, electric negative therapy, others Aerohydrotherapy, interferential current therapy (I.C.T.), Carbon, Samhogi, T.E.N.S., Ultra-sound, Infra-red, Microwave, T.D.P., Ultraviolet, S.S.P., Chinese herbs beth, Prarffin bath, Magnetic treatment and tractions.

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