• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.11B no.2
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• pp.34-39
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• 2001

This paper described the forces analysis of a hybrid linear pulse motor (HLPM) with high accuracy and repeatability. The HLPM is fed from a phase current by microstepping drive. The finite element method (FEM) is employed for calculating the force. The forces between mover(forcer) and stator(platen) have been calculated using the virtual work method. The detent force, rate of tooth width to tooth pitch and magnetic saturation were analyzed to considered the distortion characteristics of static thrust. The thrust to displacement produced a high pulsating force while the normal force is much higher than the thrust force.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.5
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• pp.746-750
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• 2015

In this paper, we propose a simulator to evaluate the performance of the semi-active laser guidance or the quadrant photodetector and to simulate the laser power reflected from a target. The laser pulse repetition frequency was generated and synchronized with the laser pulse repetition(PRF) code. To evaluate the performances of the proposed methods, we implemented a prototype system and performed experiments. As a result, the generated high voltage was variable in the range of DC 3V to 340V and has the rate of change of 2000 V/s. PRF code can be generated within 50ms ∼ 100ms and the error is implemented within 0.3ns. The laser output is synchronized with the PRF code and has a dynamic range of 23.6dB.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.8
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• pp.789-797
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• 2009

Gyroscope's deadzone is a region where can not detect the rate even though the actual rotation is applied. This paper analyzed the cause of deadzone by modeling/simulation and introduced pulse dithering method to overcome. From the testing of 3-axis fiber optic gyro system using 900m fiber, it confirmed deadzone could be effectively eliminated by combination of three factors, dither amplitude, dither frequency, and gyro loop gain.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.657-659
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• 1993

We have developed a repetitive TEA $CO_2$ laser excited by a magnetic switch pulse source, and have measured the laser output energy for the mixing ratio of the laser gas mixture in single pulse. As a result of experiments, we have obtained the laser output energy of 252 mJ($\eta_{intrinsic}$=7.8%) in $CO_2:N_2$:He=1:1:8(1 atm.). At a repetition-rate frequency of 10 Hz, an average laser power of 1.5 W was obtained.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.10a
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• pp.915-916
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• 2005

The high power RF system for the PEFP 20MeV proton accelerator composed of the 3MeV RFQ and the 20MeV DTL has been installed. The klystron for the RFQ was tested up to 600kW and operated routinely to drive the RFQ in a pulse mode operation. The klystron for the DTL which consists of 4 tanks was tested up to 800kW in pulse mode operation. The pulse width and repetition rate was 50${\mu}s$ and 1Hz respectively. The high power RF system has been operated to drive each accelerating structure and will be used to accelerate 20MeV proton beam.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.204-207
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• 2005

We discuss two possibilities of using femtosecond pulse lasers as a new interferometric light source fer enhanced precision surface profile metrology. First, a train of ultra-fast laser pulses yields repeated low temporal coherence, which allows performing unequal-path scanning interferometry that is not feasible with white light. Second, high spatial coherence of femtosecond pulse lasers enables to test large size optics in non-symmetric configurations with relatively small size reference surfaces. These two advantages are verified experimentally using Fizeau and Twyman-Green type scanning interferometers.

• Bulletin of the Korean Chemical Society
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• v.17 no.2
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• pp.143-146
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• 1996

A continuous potential pulse is applied to a silver-working electrode on a pulsed amperometric detector (PAD) for detection of free cyanide and sulfide. The moving phase is 0.1 M sodium hydroxide, 0.5 M sodium acetate and 5% (v/v) ethylenediamine mixture, and the flow rate is 0.7 mL/min. Optimized pulse conditions include a -200 mV (vs. Ag/AgCl reference electrode) detection potential(Ed) for 60 msec and 50 mV cleaning potential (Ec) for 120 msec. The silver working electrode surface is not poisoned by cyanide or sulfide, and the PAD maintains long-term stability without loss of sensitivity and reproducibility at these pulse conditions. The detection limit of cyanide and sulfide separated by ion chromatography using an anion exchange column is 0.1 ppm and 0.05 ppm, respectively.

• Science of Emotion and Sensibility
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• v.12 no.3
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• pp.299-306
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• 2009

In this study, pulse waves were measured at radial artery using non-invasive tonometric pulse pressure measurement system, SphygmoCor(AtCor, Australia), according to subject's posture. Then it was analysed whether the pulse wave parameters, which contain heart activities, change among three different postures (upright stand, sit, and supine). And it was also verified that the pulse wave parameters change among blood pressure level groups(hypotensive, normotensive, and hypertensive). As a results, posture effects were verified in time information of pulse wave rather than amplitude. But some parameters calculated by ratio of two amplitude, such as augmented index(AI) and ratio of central aortic pulse and radial artery pulse, showed significant difference according to postures. In post hoc test, time to the $1^{st}$ and $2^{nd}$ pulse peak(P_$T_1$, and P_$T_2$), ED(ejection duration), and HR(heart rate) showed significant difference among posture groups with each other. In comparison of blood pressure groups, it was verified that the parameters related to amplitude of pulse wave showed significant difference rather than time information.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.4053-4064
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• 2012

The purpose of this study was to examine the effects of aroma foot reflexology and foot reflexology on blood pressure, pulse rate and blood lipid level of elderly essential hypertensive patients in a rural area. The research method was a non-equivalent control group pretest-posttest quasi-experimental design and the participants were consisted of 71 elderly patients with essential hypertension who were being registered at C health Clinic(G gun, Chungnam province). Here, we compared experimental group I(aroma foot reflexology) 24 persons, experimental group II(foot reflexology) 27 persons and control group(conventional treatment) 20 persons to measure the effect. The data were analyzed with SPSS/WIN 12.0. The systolic blood pressure(p<.05), the diastolic blood pressure(p<.05), and the pulse rates(p<.01) of experimental group I and II after intervening respectively with aroma foot reflexology, and foot reflexology for 6 weeks were significantly decreased than the control group, but the blood lipid level was no significant difference among 3 groups(p>.05). In conclusion, both of aroma foot reflexology and foot reflexology had positive effects to decrease the blood pressure and pulse rates of the elderly essential hypertensive patients in a rural area and would be utilized as a nursing intervention for them.

• Journal of Chest Surgery
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• v.13 no.4
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• pp.455-461
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• 1980

This is one case report of surgically treated ventricular septal defect [VSD] with aortic insufficiency [AI] at department of thoracic and cardiovascular surgery, Hanyang university hospital. He had had progressive dyspnea on exertion and palpitation for 3 years prior to admission to our hospital. On examination, the blood pressure was 120/0 mmHg and the pulse rate 88 times/min. Bobbing motion of the head, Water hammer pulse, Corringan`s pulse, Quincke`s pulse and to and fro murmur were present. The heart murmur was consistent with .VSD and AI. Cardiomegaly was seen in chest X-ray. EKG, echocardiogram, aortogram and right heart catheterization was performed. On Sep. 9, 1980, open heart surgery was performed under the impression of VSD with AI. Infracrystal type VSD measuring 2 x 1.5 cm in diameter was closed with Teflon patch graft through the transverse ventriculotomy. AI was due to prolapsed, elongated right coronary and noncoronary cusp, especially noncoronary cusp. The prolapsed, elongated aortic leaflets were plicated by placing three 8-figure sutures between the free edge and the base of the leaflet [Frater`s method] through a transverse aortotomy. Postoperatively, he made an uneventful recovery, his blood pressure was 120/70 mmHg and showed no signs AI or residual shunt at discharge.