• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2009년도 춘계학술대회 논문집
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• pp.149-149
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• 2009

실제 산업에서 가장 많이 사용하고 있는 in-line type system에서 Al-doped ZnO (AZO) 막을 bipolar pulsed DC sputtering을 이용해 증착하였다. 약 30 nm/sec의 속도로 기판을 타겟 좌우로 swing 하면서 동적 증착 공정을 한 AZO 박막의 columnar structure가 정적 증착일 때와 다른 형태의 zigzag-type columnar structure가 형성되었다. 투명전도막의 가장 중요한 특성인 비저항과 투과도가 동적 증착 공정일 때의 박막과 정적 증착 공정일 때의 박막이 각각 $2.5{\times}10^{-3}{\Omega}{\cdot}cm$, 78.5%와 $1.65{\times}10^{-3}{\Omega}{\cdot}cm$, 83.9% 였다. 이렇게 성장하는 막의 구조 형태에 따라 달라지는 특성 변화는 양산하는 현장에서 매우 중요한 것이며, 동적 증착 공정에서의 박막 특성 개선에 정적 증착 공정과는 다른 방법의 연구가 필요할 것이다.

• 대한후두음성언어의학회지
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• 제20권1호
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• pp.25-30
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• 2009

Introduction: 585 nm Pulsed dye laser (PDL) laryngeal surgery is based on the photodynamic characteristics of selective photothermolysis and photoangiolysis and recently considered to be the treatment for a variety of benign laryngeal disease. Objective: To review the indications and outcome of office-based 585nm PDL surgery and summarize new developments. Method: Retrospective study involving 402 patients was performed, The PDL surgery could be applied to various laryngeal diseases such as laryngeal papilloma, vocal fold dysplasia, laryngeal granuloma, vocal polyp, capillarectasia, scarred vocal fold and sulcus vocalis. Results : The physiologic properties of the vascular specificity of PDL provide many advantages and appear to be effective for laryngeal treatment. The PDL resulted in precise, selective coagulation of the microvasculature without damage to the surrounding tissue. Therefore PDL surgery is safe and effective for office-based treatment of benign laryngeal disease and for all patients regardless of their overall medical condition. Conclusion: PDL surgery provides potential benefits and advantage for treating common benign laryngeal disease.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 E
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• pp.1900-1902
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• 1997

In order to obtain various waveforms of current pulse applied at the flashlamp, we have fabricated a Pulsed Nd:YAG laser by PFN with multiple-mesh formed LC network. we have obtained various waveforms of current pulse by adjusting the values of L and C, compared these waveforms of current pulse with laser beam, and then analyzed the laser output energy. We have got relations for $E_{TH}$ and $E_L$ at each mesh which supplies energy with flashlamp and found that output of Pulsed Nd:YAG Laser for 2-mesh, 5-mesh coincided with computer's simulation, PSPICE.

• 한국분말재료학회지
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• 제12권1호
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• pp.24-29
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• 2005

Nano Fe-6.5wt%Si powders have been synthesized by mechano-chemical process (MCP) for an application of soft magnetic core. Owing to hard and brittle characteristics of Fe-6.5Si nano powders having large surface area, it is very difficult to reach high density more than 70% of theoretical density (~7.4 g/$cm_3$) by cold compaction. To overcome such problem a magnetic pulsed compaction (MPC), which is one of dynamic compaction techniques, was applied. The green density was achieved about 78% (~5.8 g/$cm_3$) by MPC at room temperature.

• Journal of international Conference on Electrical Machines and Systems
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• 제1권3호
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• pp.282-288
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• 2012

A special pulsed electromagnetic actuator is presented whose plunger consists of two parts made of carbon steel and permanent magnet, respectively. The actuator exhibits a high holding force and small consumption of energy. The movement of the plunger is controlled by short current pulses. The static characteristics and other operation properties of the device are modeled numerically.

• KIEE International Transactions on Electrophysics and Applications
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• 제3C권6호
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• pp.241-245
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• 2003

ZnO thin films on (l00) p-type Si and sapphire substrates have been deposited by a pulsed laser deposition technique using an Nd:YAG laser with a wavelength of 266 nm. The influence of the deposition parameters such as oxygen pressure, substrate temperature and laser energy density on the properties of the grown films was studied. The experiments were performed for substrate temperatures in the range of 200∼50$0^{\circ}C$ and oxygen pressure in the range of 100∼700 sccm. All of the films grown in this experiment show strong c-axis orientation with (002) textured ZnO peak. With increasing substrate temperature, the FWHM (full width at half maximum) and surface roughness were decreased. In the case of using sapphire substrate, the intensity of PL spectra increased with increasing ambient oxygen flow rate. We investigated the structural and morphological properties of ZnO thin films using X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM).

• Bulletin of the Korean Chemical Society
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• 제25권12호
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• pp.1859-1862
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• 2004

Europium doped yttrium vanadate ($YVO_4$:Eu) phosphor thin films were grown using a pulsed laser deposition (PLD) technique on silicon substrate. The structural characterization carried out on a series of ($YVO_4$:Eu films at post annealing temperature in the range of 550 $^{\circ}C$-1150 $^{\circ}C$ indicating that films were preferentially (200) oriented at post annealing temperature above 950 $^{\circ}C.$ Photoluminescence of thin film increased with the increase of post annealing temperature and ambient oxygen pressure though the thin film has the powder-like surface morphology at oxygen pressure above 200 mTorr. Photoluminescence decay from $^5D_1$ level of $Eu^{3+}$ show the great concentration dependency, which can be used as a good parameter to control the composition of ($YVO_4$:Eu thin film.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.368-369
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• 2006

By means of magnetic pulsed compaction and sintering of weakly aggregated alumina based nanopowders the jet forming nozzle samples for the hydroabrasive cutting were fabricated. The ceramics was obtained from pure alumina, as well as from alumina, doped by $TiO_2$, MgO and AlMg. It was shown that the samples sintered from AlMg doped $Al_2O_3$ powder have the best mechanical properties and structural characteristics: relative density ${\sim}0.97$, channel microhardness. - 18-20 GPa, channel surface roughness ${\sim}0.7\;{\mu}m$, average crystallite size ${\sim}1\;{\mu}m$.

• 한국분말재료학회지
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• 제10권4호
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• pp.275-280
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• 2003

Synthesis and characteristics of Cu nanopowder were considered by in-situ characterization method using SMPS in pulsed wire evaporation process. With increasing pressure in chamber, particle size and degree of agglomeration increased by increase of collision frequency. Also, it was found from the XRD analyses and BET measurements that crystallite size and particle size decreased with elevating applied voltage. However, SMPS measurements and TEM observation revealed the increase of particle size and degree of agglomeration with increase of applied voltage. These results suggested that particle growth and agglomeration depend on overheating factor in chamber at the early stage and thermal coagulation in filtering system during powder formation until collection.

• 한국세라믹학회지
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• 제56권1호
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• pp.1-23
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• 2019

Dielectric materials with inherently high power densities and fast discharge rates are particularly suitable for pulsed power capacitors. The ongoing multifaceted efforts on developing these capacitors are focused on improving their energy density and storage efficiency, as well as ensuring their reliable operation over long periods, including under harsh environments. This review article summarizes the studies that have been conducted to date on the development of high-performance dielectric ceramics for employment in pulsed power capacitors. The energy storage characteristics of various lead-based and lead-free ceramics belonging to linear and nonlinear dielectrics are discussed. Various strategies such as mechanical confinement, self-confinement, core-shell structuring, glass incorporation, chemical modifications, and special sintering routes have been adopted to tailor the electrical properties and energy storage performances of dielectric ceramics. In addition, this review article highlights the challenges and opportunities associated with the development of pulsed power capacitors.