• Journal of Korea Water Resources Association
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• v.41 no.7
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• pp.711-723
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• 2008

In this study, Hydrologic regime alterations(magnitude, magnitude and duration of annual extreme, frequency and duration of high and low pulse, rate and frequency of water condition changes, Range of Variability Approach) were analyzed by using Indicators of Hydrologic Alterations at the 11 major multi-purpose dam. The analysis result of the magnitude of monthly water conditions during drought season, inflow was $6.38m^3/sec{\sim}39.84m^3/sec$ and outflow was $20.36m^3/sec{\sim}49.43m^3/sec$, was increased $1.84%{\sim}200.98%$. The analysis result of the magnitude of monthly water conditions during flood season, inflow was from $79.06m^3/sec{\sim}137.12m^3/sec$ and outflow was from $65.32m^3/sec{\sim}80.16m^3/sec$, was decreased from $18.19%{\sim}40.39%$. The analysis result of the magnitude and duration of annual extreme, 1-day minimum was increased $82.86%{\sim}2,950%$, but 1-day maximum was decreased $34.78%{\sim}83.96%$. The analysis result of the frequency and duration of high and low pulse, low pulse count was decreased $29.67%{\sim}99.07%$ and high pulse count was also decreased $4.6%{\sim}92.35%$ after dam operation. Hydrograph rise rate was decreased $15.84%{\sim}79.31%$ and fall rate was $1.97%{\sim}107.10%$. RVA of 1-day minimum was increased $0.60{\sim}2.67$, also RVA of 1-day maximum was decreased $0.50{\sim}1.00$.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.10a
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• pp.3-11
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• 1998

Response of tall buildings to near-field ground motions with distinct low-frequency pulses can differ dramatically from, for example, the response to the 1940 El Centro ground motion. For the same peak ground acceleration (PGA) and duration of shaking, ground motions with a pulse-like characteristic can generate much higher base shear, inter-story drifts and roof displacement in a high-rise building as compared to ground motions without the characteristic pulse. Also, the ductility demand is much higher and the effectiveness of supplemental damping is lower for pulse-like ground motions. This paper presents a simple interpretation of the response characteristics for two recorded and one synthetic near-field pulse-like ground motions.

• Journal of Korea Water Resources Association
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• v.41 no.2
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• pp.163-172
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• 2008

Hydrologic regimes play a major role in determining the biotic composition, structure, and function of river ecosystem. In this study, hydrologic regimes were analyzed on down stream effects of the Young-Chun dam construction using the Indicators of Hydrologic Alterations(IHA). The analysis results were as follows ; (1) Monthly mean flows were decreased during drought and flood season on the pre and post dam, (2) Magnitude and Duration of Annual Exterm Conditions, annual minima 1-day means was $3.48m^3/sec$, $0.89m^3/sec$ and annual maxima 1-day mean was $833.1m^3/sec$, $672.1m^3/sec$ on the pre and post dam (3) Timing of Annual Exterm conditions, Julian date of the annual minima 1-day means was 180th(June) in the pre dam, 257th(September) in the post dam, Julian date of the annual maxima 1-day means was 209th(July) in the pre dam, 217th(August) in the post dam, (4) Frequency and Duration of High and Low Pulse, Low Puls counts and duration were 3 times and 23 days in the pre dam, High Pulse counts and duration were 4 times and 2 days in the pre dam. (5) Rate and Frequency of Water Condition Changes, rise rates was 39.27 %, 19.36 % and fall rates -15.85 %, -8.16 % in the pre and post dam, respectively (6) Coefficient of Variation, annual exteram water conditions were decreased from 0.9054 to 0.6314 and from 1.0440 to 0.9617, Timing of Annual Exterm conditions were incereased for minima flow from 0.269 to 0.282, for maxima form 0.069 to 0.153.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1400-1404
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• 2005

This paper presents the temperature control of aluminum plate by using Peltier element. Peltier effect is heat pumping phenomena by electric energy as one of the thermoelectric effect. So if current is charged to Peltier element, it absorbs heat from low temperature side and emits heat to high temperature side. In this experiment, Peltier element is used to control the temperature of small aluminum plate with current control and operating cooling fan only while cooling duration. Operating cooling fan only while cooling duration is proper to get more rapid heating and cooling duration. As a result of experiment, it takes about 100sec period to repeating temperature between $35^{\circ}C$ and $70^{\circ}C$ and about 80sec from $40^{\circ}C$ to $70^{\circ}C$ in ambient air temperature $25^{\circ}C$ and while operating cooling fan only in cooling duration. Future aim is to apply this temperature control method in actuating SMHA(special metal hydride actuator) which is applicable in Siver project acting in low frequency range by using Peltier element for heating and cooling.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.4
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• pp.60-67
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• 2005

Compared with conventional welding, laser spot welding offers a unique combination of high speed, precision and low heat distortion. This combination of advantages is attractive for manufacturing industries including automotive and electronics companies. In this paper, a real time monitoring scheme fur a pulsed Nd:YAG laser spot welding was suggested. Acoustic emission (AE) signals were collected during welding and analyzed for given process conditions such as laser power and pulse duration. A back propagation artificial neural network, with AE frequency content inputs, was used to predict the weldability of stainless steel sheets.

• The Journal of Korean Obstetrics and Gynecology
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• v.31 no.1
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• pp.57-83
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• 2018

Purpose: This research has been carried out to find out correlation between test results of ABR-2000 and other diagnostic equipments to enhance significance of accurate diagnosis and clinical usage of ABR-2000. Methods: Duration of the 31 months from December 2012 to June 2015, records of 564 outpatients at gynecology department have been selected. The 564 patients were tested, using all 3 different test equipments of ABR-2000, DSOM, and 3D Blood Pressure Pulse Analyzer (3D-MAC) without test errors or mis-recordings. Correlation between 3D Blood pressure Pulse Analyzer, DSOM and ABR-2000 were analyzed by frequency & ratio factor of statistic data records of patients groups devided by 8 different disease symptom and by comparison of the groups in the form of Regulation and Graph presented on ABR-2000 equipment. Results: 1. The indicator L in all 1, 2, and 3 quadrant in the graph means the activity and reactivity of the upper body biodynamics detection rate is low and which result is very common symptom among gynecological patients. 2. The portion of patients with hypermenorrhea, endometritis, and menstrual pain symptom among the indicator L group in the reactivity 1-3 quadrantin is significantly high. 3. When 3D Mac analyzer indicates H, diastole decreases while systole increases and tachycardia increases then the blood circulation is expected to increase. In case of indication L, diastole increases and systole decreases then, the blood circulation is expected to decrease.

• Journal of Acupuncture Research
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• v.17 no.2
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• pp.209-220
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• 2000

Spasticity, an abnormal increase in resting muscle tone, is one of the most common symptoms of stroke, and its management is becoming a major issue in rehabilitation. The aims of this study are to determine the effects of electroacupuncture(EA), TENS and neuromuscular electric stimulation(NMES) on spasticity, as well as the possibility of tissue comliance method as a spasticity scale. 45 stroke patients participated in a study of the effects on hemiplegic spasticity of EA, TENS and NMES. Spasticity was measured by modified Ashworth scale on the upper extremity and tissue compliance measurement, penetration mm/kg, on Susamni(LI10) area at just before and after stimulation, and 30 minutes, 1 hour, 2 hours and 24 hours after stimulation. The acupuncture points were applied to Kokchi(LI11), Susamni(LI10), Hapkok(LI4) and Oegwan(TE5) of the affected limb. The electrodes were placed unilaterally on LI11 to LI10 and TE5 to LI4. EA with biphasic wave, 60Hz, 0.4 msec pulse duration and low intensity was applied continuously for 20 minutes. TENS with high frequency, low intensity was applied. NMES was applied with spasticity program for 20 minutes. Each electric stimulation was done on extensor muscles group of forearm for 20 minutes. EA and NMES groups were found to produce a statistically significant decrease(p〈0.05) of spasticity and these effects lasted up to 30 minutes after stimulation. There was no definite correlation between the modified Ashworth scale and tissue compliance measurement. But tissure compliance method was found to be possible as a quantitative measurement on spasticity. There was no significant correlation between the effects of EA and NMES and the characteristics of patient, but significant correlation between the effects of EA and NMES and the modified Ashworth scale.