• Current Optics and Photonics
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• v.4 no.3
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• pp.238-246
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• 2020

The heat distribution in crystals in a 2-㎛ acousto-optic Q-switched Tm:LuAG laser pumped by pulsed-laser-diode (pulsed-LD) intermittent-pumping technology was analyzed using COMSOL software. The thermal lensing effect of the Tm:LuAG crystal can be mitigated by pulsed-LD intermittent-pumping techniques. An experimental setup using this kind of approach achieved maximum output energy of 8.31 mJ, minimum pulse width of 101.9 ns, and highest peak power of 81.55 kW, reached at a Q-switched repetition rate of 200 Hz. It offers significant improvement of performance of the output laser beam, compared to pulsed-LD double-ended pumping technology at the same repetition rate.

• Journal of the Korean institute of surface engineering
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• v.32 no.3
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• pp.467-471
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• 1999

BN films were grown on silicon (l00) substrate by magnetically enhanced activated reactive evaporation (ME-ARE) with pulsed DC power instead of r.f. for substrate biasing. The deposited films were analyzed using Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). FTIR results show that the intensity of absorption band of $sp^2$ bond of BN decreased and that of $sp^3$ bond of c-BN increased with increasing pulsed DC bias voltage applied to substrate. The initially grown layer at the interface was observed by TEM and considered to be of$ sp^2$-bonded BN. The cross-sectional and planar TEM micrographs show that the upper layer on the initial layer was the single phase c-BN. It is concluded that cubic boron nitride films could be synthesized by ME-ARE process with pulsed DC biasing.

• The Journal of Korean Physical Therapy
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• v.23 no.4
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• pp.53-58
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• 2011

Purpose: This study aims to examine the effects of pulsed ultrasound on skin inflammatory reaction induced by ultraviolet irradiation. Methods: Twenty subjects were selected for this study. Inflammatory reaction was induced by ultraviolet irradiation in two areas of the lumbar region of the subjects. Pulsed ultrasound (3 MHz) was applied to one of the two areas of inflammatory reaction at a pulse ratio of 1:4, intensity of $0.5W/cm^2$, once a day for 5 min, and pulsed ultrasound was not applied to the other area. Wound color (chromatic red), luminance (gray) and wound contraction (area) were measured using digital imaging processing method. Results: There was a significant difference in wound color (chromatic red) in the interaction between time and area. There was a significant difference in luminance in the interaction between time and area. There was a significant difference in wound contraction between the two areas. Conclusion: These results indicate that pulsed ultrasound increased the wound contraction rate and reduced the inflammatory reaction activity such as erythema induced by ultraviolet irradiation.

• Progress in Superconductivity and Cryogenics
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• v.21 no.1
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• pp.1-5
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• 2019

The pulsed field magnetization of the short-circuited soldered double pancake coil made of stabilized commercial high-Tc superconductor (HTS) tape is experimentally studied. The evolution of the shielding current induced by the pulsed field and the trapped field after the pulsed magnetization was measured at 77 K. It is shown that the trapped field in the coil is close to the value reached in the field cooling process and reduces weakly at 5-fold increasing of pulsed field amplitude. The current relaxation at t~2 ms after the pulse is defined by the current sharing between the tape's copper coating and the $YBa_2Cu_3O_{7-d}$ layer. In the intermediate time scale (1 s < t < 100 s) the flux creep in HTS layer dominates. At t > 100 s the current's relaxation is defined by the resistance of soldered joint between tapes.

• Korean Journal of Materials Research
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• v.14 no.9
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• pp.619-626
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• 2004

Pulsed metalorganic chemical vapor deposition (MOCVD) of conformal copper seed layers, for the electrodeposition Cu films, has been achieved by an alternating supply of a Cu(I) source and $H_2$ reactant at the deposition temperatures from 50 to $100^{\circ}C$. The Cu thickness increased proportionally to the number of cycles, and the growth rate was in the range from 3.5 to $8.2{\AA}/cycle$, showing the ability to control the nano-scale thickness. As-deposited films show highly smooth surfaces even for films thicker than 100 nm. In addition about a $90\%$ step coverage was obtained inside trenches, with an aspect ratio greater than 30:1. $H_2$, introduced as a reactant gas, can play an active role in achieving highly conformal coating, with increased grain sizes.

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.60-60
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• 2002

• Proceedings of the Materials Research Society of Korea Conference
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• 2001.05a
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• pp.104-104
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• 2001

• Journal of the Korean Professional Engineers Association
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• v.15 no.3
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• pp.12-18
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• 1982

Preliminary investigation have been made on what the capacity of high rate pulsed discharge of Ago-Zn button cells were associated with the changes of cathode construction feature, mix formulation, separator and electrolyte concentration.

• Proceedings of the Materials Research Society of Korea Conference
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• 1996.05a
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• pp.155-157
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• 1996

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.33.2-33
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• 2002