• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1779-1781
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• 1998

We are going to design the Square Pulse Generator use of PCPS (Photo-Conductive Power Switch) for Blumlein lain. The circeuit is made of LC device and it is simulated by Schematics Evaluation Version 8.0 of MicroSim. After charged by DC voltage 15[kV]. When the switch is ON, Square pulse is generated after pause time 1.7857[${\mu}s$]. The square pulse is maximum peak voltage 13.987[kV], pulsed width 3.4017[${\mu}s$], rising time 0.7474[${\mu}s$], falling time 1.1718[${\mu}s$].

• Journal of the Korean Society for Precision Engineering
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• v.27 no.1
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• pp.99-104
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• 2010

Magnesium and magnesium alloys, the lightest structural materials, have been received plenty of global attention recently. These alloys could be applied in various fields, especially the electronics industry, because of their excellent electromagnetic interference shielding. However, the welding technique of magnesium alloys has not been established. This study is related to the welding of AZ31B magnesium alloy by a short-pulsed a Nd:YAG laser. Two types of pulse waves, square pulse and variable pulse, were used to control weld defects. Results show that the crack and porosity, generated in the weld, had not been controlled by general square pulse. But through the application of variable pulse, the defects could be prevented and the good weld zone was obtained.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.506-514
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• 2007

In this study, carrot juice was treated with high voltage pulsed electric fields (PEF) and the changes in its physical and chemical properties during storage at $4^{\circ}C$ and $25^{\circ}C$ were investigated. The sterility fur bacteria, yeast and mold in carrot juice increased with increasing electric field strength and treatment temperature. While yeast and mold were completely inactivated at 65kV/cm with a treatment time of $200{\mu}s$ in a continuous PEF treatment system, bacteria were reduced by four log cycles. The results also showed that square wave pulse treatment was more effective for inactivating microorganisms than exponential decay pulse, and this effect was more apparent for carrot juice of lower pH. Although we observed significant changes in physical and chemical properties such as soluble solid content, pH, acidity, color, and carotene retention when the PEF treated samples were stored at the ambient temperature $(20^{\circ}C)$, no significant physical and chemical changes were found at the cold storage temperature $(4^{\circ}C)$ during 28 days of storage. The results indicate that the PEF treated carrot juice is appropriate for commercial refrigerated storage.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.49 no.4
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• pp.111-119
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• 2012

Time Stretched Pulse (TSP) is used for transmitting and analyzing the impulse signal over the designated spatial place. However, if transfer functions of transmitter and receiver are unknown, performance investigation of free field in temporal domain is barely possible due to the overlap between the direct and indirect signal from the space. Generally, the free field or hemi-free field is evaluated by the Annex A of ISO 3745 in which utilizing the inverse square law with one-third octave band signals. In this paper, the author performs analysis of free field via applying TSP with inverse square law and the results are compared with the one-third octave band signals. According to the analysis of deviation between the corresponding signal and inverse square law model, the proposed TSP method provides the comparable performance index to the one-third octave band signal with reduced measuring time. Provided that the pre-whitening can be implementable by employing the speaker and microphone transfer function, further analyses from TSP compression are able to be performed such as multipath separation from time domain data. The anechoic chamber used in this experiment is verified conformance with ISO 3745 for free field and hemi-free field condition for limited frequency of the signal.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.609-612
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• 2002

A new reset waveform is proposed for reducing the reset period. A square pulse is applied to the address electrode while reset pulse ramps and before a discharge between the sustain electrodes occurs. The square pulse induces a discharge between the address electrode and the X electrode, and the induced wall charge is opposite to the applied ramp pulse. Thus, the next discharge between the sustain electrodes becomes weaker. The weaker discharge lowers background luminance and improves contrast ratio. Thus, the new reset waveform can reduce ramp up time in the ramp reset waveform The experimental results show that the ramp up time can be reduced by about 90% compared with the conventional ramp reset waveform.

• Journal of Korean Medical classics
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• v.23 no.1
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• pp.101-114
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• 2010

In the perspective of the correspondence of heaven and man[天人相應], people live through Gi of heaven and earth[天地之氣], and the human body which is a small universe[小宇宙] itself receives influence while sympathizing with the Gi and heaven[天氣]. So with unexpected incident of the Eum and Yang, four season[陰陽四時], ups and downs of warmth of cold and chilliness of warm[寒熱溫涼] differs, and the position of Gi of human[人氣] changes, regimen and application of acupuncture, and images[象] of the pulse changes. In "Maekyojeongmiron(脈要精微論)", ups and downs of Eum and Yang changes by four season[四時], and correspondence of ups and downs of pulse law is explained with compass, carpenter's square, the beam of balance and the weight of balance[規矩權衡]. Compass[規] is a measure of instrument that can draw a circle, like regulating the measure and differing the center of the circle and diameter and drawing a circle, compass is a image of Gi of Yang[陽氣] that was staying deep inside the body in winter stretching out by big fault[太過不及] of year and energy[元氣] of human in spring. Carpenter's square[矩] is a instrument that draws direction, which is a image of Gi of Yang flourishing in summer and when it gets highly flourished, again the Gi of Eum[陰氣] comes alive and falls. The beam of balance[衡] is a scale, like a scale that tilts at once when one side is slightly heavy, the beam of balance is a image Gi of yang that is fully flourished in summer and about to descent again, which is just about to fall but not going down yet. The weight of balance [權] is a image of gi of yang which as descent to the bottom and staying in the deepest place. compass, carpenter's square, the beam of balance and the weight of balance is not a direct pulse image[脈象], but standard image of pulse of pulse corresponding to the Gi of human[人氣] that changes by four season, and the explanation includes the pulse image of four season like the taut, full, floating, deeply gather[弦鉤浮營] of "Okgijinjangron(玉機眞藏論)" or taut, full, skip, float, deep [弦鉤代毛石] of "Pyeong-ingisangron(平人氣象論)". So with compass, carpenter's square, the beam of balance and the weight of balance, can judge is human correspond in Eum and Yang, four seasons, this is importantly used in examination of pulse[診脈] with existence and nonexistence, and prognosis of illness.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.12
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• pp.573-578
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• 2003

In this study, new type of induction charging system for electrostatic spraying was manufactured and proposed to improve the electrical safety and charging efficiency. And parameters of proposed system to generate the maximum deposition current with electrical safety were selected and investigated. The selected parameters were frequency of square pulse and thickness of insulation material, outer diameter of device and thickness and positions of electrode. Charging quantity of water drop was measured by deposition current detected from sensing plate indirectly. The maximum deposition current for each parameter were 3.5[uA] at the frequency of 15[kHz] and thickness of 0.25[mm] insulating layer. And maximum deposition currents were 2.8[uA] and 3.0[uA] at 25[mm] outer diameter of charging device and 0.25[mm] thickness of electrode each. Effects of electrode position from spraying nozzle on deposition current was a little.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.11a
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• pp.69-69
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• 2012

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.132-135
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• 2001

The design of square pulse generators using pulse forming lines (PFLs) made up of identical L and C, was reviewed in this study. 14 different types of PFLs were analyzed utilizing PSpice simulation results. These PFLs were characterized with respect to their distinct features: the number of forming lines (single or double), the circuit relationship between PFL and load (parallel or series), the types of energy storage (voltage source, current source or a combination of both). The characteristic impedances, output parameters such as pulse width, voltage and current magnitudes, and powers were derived for each scheme. The merits and demerits of the output parameters were also included.

• Journal of Advanced Navigation Technology
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• v.10 no.4
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• pp.333-341
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• 2006

This paper analyzes the spectral power properties of various time hopping UWB signals and shows that the power spectral densities of the various signals could have to be determined by the PSD of the pulse used in the signal. The pulse design method by which the FCC emission mask can be utilized fully is proposed. The method combines the arbitrary derivative Gaussian pulse linearly. The coefficients of the linear combination are calculated by the LSE(Least Square Error) method. Various parameters such as the number of coefficients and the types of the basic pulses are considered when calculating the PSD and pulse shapes of the new pulses.