• Title/Summary/Keyword: Time Duration

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Operating characteristics of high Tc superconducting current limiting fuse at various voltages (고온 초전도 한류퓨즈의 전압별 동작특성)

  • Choi, Hyo-Sang;Hyun, Ok-Bae;Kim, Hye-Rim;Hwang, Si-Dole;Park, Kwon-Bae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.05c
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    • pp.161-163
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    • 2001
  • We present the basic properties of a superconducting current limiting fuse (SCLF) based on YBCO/Au films. The SCLFs consists of YBCO stripes covered with Au layers for current shunt. Under the source voltage of 100 $V_{rms}$, the longer the duration time of fault current was, the shorter its discharge time was. The duration time of fault current and its discharge time were reduced by increased voltages in the range of 200 - 300 $V_{rms}$. We thought that this was because the quench propagation was limited by local melting generated with higher voltage.

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A Real Time Automated Diagnosis Algorithm of Electrocardiogram Based-on Microcomputer (마이크로 컴퓨터를 이용한 실시간 ECG 자동진단 알고리즘)

  • 윤형로;최경훈
    • Journal of Biomedical Engineering Research
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    • v.6 no.1
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    • pp.55-64
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    • 1985
  • The cardiac activation process using three dimensional ventricular model is simulated.To study this theme, we constructed a cardiac ventricular model and simulated the cardiac activation process using the action potential duration and the activation time. The cardiac ventricular model is generated by the logical combination of the elliptic equations. The action potential duration could be obtained from the fact that it is linearly distributed between model cells. The cardiac activation process was simulated by the law of "all-or-none" Based on the activation time and the action potential do-ration the cardiac potential at the arbitrary time after the activation of the model cell was computed. To test the validity of model, the comparison of the results of model simulation with the physiological data was performed. In conclusion, this model shows the simular results which is comparable to the real conduction of the cardiac excitation.xcitation.

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Control and Parameter Estimation of Uncertain Robotic Systems by An Iterative Learning Method (불확실한 로보트 시스템의 제어와 파라미터 추정을 위한 반복학습제어)

  • 국태용;이진수
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.40 no.4
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    • pp.427-438
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    • 1991
  • An iterative learning control scheme for exact-tracking control and parameter estimation of uncertain robotic system is preented. In the learning control structure, the control input converges globally and asymtotically to the desired input as iteration increases. Since convergence of parameter errors depends only on the persistent exciting condition of system trajectories along the iteration independently of the time-duration of trajectories, it may be achieved with system trajectories with small duration. In addition, the proposd learning control schemes are applicable to time-varying parametric systems as well as time-invariant systems, because the parameter estimation is performed at each fixed time along the iteration. In the parameter estimator, the acceleration information as well as the inversion of estimated inertia matrix are not used at all, which makes the proposed learning control schemes more feasible.

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Characteristics of a superconductive fuse according to applied voltages (초전도 퓨즈의 전압별 특성)

  • Choi, Hyo-Sang
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.05b
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    • pp.169-172
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    • 2004
  • We present the basic properties of a superconducting current limiting fuse (SCLF) based on YBCO/Au films. The SCLFs consists of YBCO stripes covered with Au layers for current shunt. Under the source voltage of 100 $V_{rms}$, the longer the duration time of fault current was, the shorter its discharge time was. The duration time of fault current and its discharge time were reduced by increased voltages in the range of 200 - 300 $V_{rms}$. We thought that this was because the quench propagation was limited by local melting generated with higher voltage.

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대기시간이 서비스 품질평가에 영향을 미치는 과정에 있어서 매개변수 및 조절변수에 관한 연구

  • Jo, Jeong-Eun;Kim, Su-Uk
    • Proceedings of the Korean Society for Quality Management Conference
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    • 2006.04a
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    • pp.14-19
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    • 2006
  • This study examined the effect of waiting in a service queue on the evaluation of service quality focused on its overall process, mediators and moderators The conceptual model of this paper integrates key variables derived from previous studies of consumer waiting behavior. Data obtained from actual customers in service queue at a hospital was used to test the theoretical framework. First, results from the path analysis confirm that negative affect and acceptability of the wait function as mediators in the process that the perceived duration of the wait affects customer's evaluation of overall service quality. Second, the analysis of the data, with the use of moderate regression shows that disconfirmation of wait time expectations, transaction importance, stability of wait time and wait environment work as moderate variables for the relationship between perceived duration of wait and negative affect. For the relationship between perceived wait time and acceptability of the wait, on the other hand, only transaction import ante shows a significant effect as a moderator.

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Time-Domain Read-Out Circuit for Inductive Sensor Applications (인덕티브 센서 응용을 위한 시간 영역 리드아웃 회로)

  • Jong-Yeob Oh;Sung-Hun Jo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.18 no.4
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    • pp.625-640
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    • 2023
  • This paper propose a circuit that can measure the inductance of an inductive sensor used in IOT applications. The circuit was constructed using the characteristics of an RL low-pass filter circuit, comparator, current control switch, and capacitor, and the inductance value within the range 1[nH] < L ≤ 1[H] can be derived through the duration time during the output voltage of the RL low-pass filter circuit is greater than the reference voltage.

A Study on the Applicability of Load Duration Curve for the Management of Nonpoint Source Pollution in Seohwacheon Basin (서화천 유역 비점오염원 관리를 위한 부하지속곡선 적용성 연구)

  • KAL, Byung-Seok;MUN, Hyun-Saing;HONG, Seon-Hwa;PARK, Chun-Dong;MIN, Kyeong-Ok;PARK, Jae-Beom
    • Journal of the Korean Association of Geographic Information Studies
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    • v.23 no.3
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    • pp.174-191
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    • 2020
  • In this study, we analyzed the vulnerable areas of non-point source pollutants and management pollutants and management time by subwatershed curves in the Seohwacheon basin located upstream of Daecheongho. First, in order to create a load duration curve, a long-term flow model SWAT was constructed to create a flow duration curve, and the result was multiplied by the target water quality to create a load duration curve. For the target water quality, monitoring data values measured from November 2017 were used for the management of nonpoint source pollutants in Seohwacheon, and a value corresponding to 60 percentile of the measured data was set as the target water quality. At this time, the target water quality was limited to"slightly good"(II) when the calculated value exceeded"slightly good"(II) of the river living environment standard. The vulnerable areas of non-point source of pollution were selected using the excess rate exceeding the target water quality, and the excess pollutant was judged as a management substance and the management time was selected through seasonal evaluation.

Design of Road Surface Drainage Facilities Based on Varied Flow Analysis (부등류 해석을 기반으로 한 노면배수시설 설계)

  • Ku, Hye-Jin;Kim, Jin-Soo;Park, Hyung-Seop;Jun, Kyung-Soo
    • Journal of Korea Water Resources Association
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    • v.41 no.12
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    • pp.1173-1185
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    • 2008
  • The design methods of the road surface drainage facilities were compared for the improvement of design method. We have developed four computational design models classified by the methods to determine the duration of design rainfall and to analyze the flow of a linear drainage channel. The critical duration was determined by assuming the critical duration to be 10 minutes or by finding the duration of design storm being similar to the travel time of flow by trial and error. The flow of a linear drainage channel was analyzed as the uniform flow or the varied flow. The design models were applied to the artificial road surface drainage facilities with various channel slopes and road shoulder slopes. If the rainfall intensity of the 10 minutes duration was applied, the outlet spacing obtained from the design based on the varied flow analysis was larger than the uniform flow analysis only when the channel slope and the road shoulder slope was small. On the other hands, if the duration of design rainfall was determined by calculating the travel time, the varied flow analysis brought about larger outlet spacing than the uniform analysis for all conditions. However, the model of the critical duration concept and the varied flow analysis resulted in smaller outlet spacing than the current design method employing the rainfall of 10 minutes duration and the uniform flow analysis.

Stochastic Method to Assess Voltage Sag Performance Considering Sag Duration in Large Power System (대규모 계통에서의 순간전압강하 지속시간을 고려한 추계적 평가 방법)

  • Lee, Myeong-Cheol;Park, Chang-Hyun
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.30 no.2
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    • pp.85-92
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    • 2016
  • The paper presents a method to assess system voltage sag performance considering sag durations as well as magnitudes. In general, voltage sag assessment for large power systems is performed only considering sag magnitudes at sensitive load points. However some equipment can be affected by certain sag durations. The duration of the voltage sag is depend on the time of fault current flow in the system. Therefore, the duration can be determined by analyzing the operating characteristic of the protection system. In this paper, an effective method to evaluate sag durations regarding the characteristics and failure rates of the protection system is described. The proposed method can be used to assess the long-term performance of the voltage sags in large power system.

Reinterpretation of the Perception of Place Cues in the Reduced Closure Duration of Stop Consonant Clusters (폐쇄자음군의 폐쇄구간 축소에 따른 위치성 지각에 대한 재해석)

  • 이석재
    • MALSORI
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    • no.45
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    • pp.1-14
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    • 2003
  • This paper criticizes S. Kim (1992), claiming that the perception of place cues in the reduced stop consonant clusters ('reducing' means 'cutting off' the acoustic silence in stop clusters) largely depends on the acoustic characteristics such as formant transition and noise frequency distribution of stop burst, rather than the closure duration time as advocated by S. Kim (1992). The claim is based on the perception test conducted upon 111 stimuli over 10 subjects. The finding is that, when the closure duration is cut off up to the point where only one stop is perceived, place of the second stop, not the first one, in the cluster is in most cases perceived regardless of the places of the first and second stops. It is likely that the place cues of the stop in the prevocalic position mask those in the postvocalic position.

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