• The Optical Journal
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• v.13 no.2 s.72
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• pp.45-48
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• 2001

향후 DPSS레이저 기술은 FPSS 레이저와 같은 수 키로와트 급 고출력 레이저의 실용화에 집중되고 있다. 키로 와트급 DPSS 레이저가 보편화 될 경우 현재 비반도체 레이저 시장에서 가장 큰 부분을 차지하고 있는 재료 가공용 고출력 레이저 시장의 대부분이 DPSS레이저로 대체되어 시장 규모가 엄청나게 증가할 것이다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.731-732
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• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.417-418
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.373-374
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• 2008

• Laser Solutions
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• v.6 no.1
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• pp.9-16
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• 2003

Micromachining using the DPSS 3rd Harmonic Laser (355nm) has outstanding advantages as a UV source in comparison with Excimer lasers in various aspects such as maintenance cost, maskless machining, high repetition rate and so on. It also has the greater absorptivity of many materials in contrast to other IR sources. In this paper, the process for micro-drilling of blind hole in Cu/PI/Cu substrate with the DPSS UV laser and the scanning device is investigated by the experimental methods. It is known that there is a large gap between the ablation threshold of copper and that of PI. We use the Archimedes spiral path for the blind hole with different energy densities to ablate the different material. Finally, the blind via hole of diameter 100$\mu\textrm{m}$ and 50$\mu\textrm{m}$ was drilled.

• Laser Solutions
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• v.15 no.4
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• pp.16-19
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• 2012

Due to the fact that the dimensions of circuit lines of IC substrates have been forecast to reduce rapidly, engraving the circuit line patterns with laser has emerged as a promising alternative. To engrave circuit line patterns in an IC substrate, we used a projection ablation technique in which a metal (INVAR) mask and a DPSS UV laser instead of an excimer laser are used. Results showed that the circuit line patterns engraved in the IC substrate have a width of about 15um and a depth of $13{\mu}m$. This indicates that the projection ablation with a metal mask and a DPSS UV laser could feasibly replace the semi-additive process (SAP).

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.411-414
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• 2011

This paper describes a tripple-mode DC-DC buck converter with DPSS Fucntion. The DC-DC buck converter operate in PWM(Pulse Width Modulation) mode at moderate to heavy loads(80mA~500mA), in PFM(Pulse Frequency Modulation)at light loads(1mA~80mA), and in LDO(Low Drop Out) mode at the sleep mode(<1mA). In PFM mode DPSS(Dynamic Partial Shutdown Strategy) is also employed to increase the efficiency at light loads. The triple-mode converter can thus achieve high efficiencies over wide load current range. The proposed DC-DC converter is designed in a CMOS 0.18um technology. It has a maximum power efficiency of 97.02% and maximum output current of 500mA. The input and output voltages are 3.3V and 2.5V, respectively. The chip size is $1465um{\times}895um$ including pads.

• Laser Solutions
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• v.8 no.1
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• pp.1-8
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• 2005

• Journal of the Institute of Convergence Signal Processing
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• v.14 no.2
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• pp.70-76
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• 2013

In this paper, we propose the bandpass form of discrete prolate spheroidal sequences(DPSS) which have the maximal energy concentration in a given passband and as such are very appropriate to obtain a projection of signals. The basic properties of the bandpass DPSS are also presented. Assuming a signal satisfies the finite time support and the essential band-limitedness conditions with a known center frequency, signal representation and interpolation techniques for band-limited signals using the bandpass DPSS are introduced where the reconstructed signal has minimal out-of-band energy. Simulation results are given to present the usefulness of the bandpass DPSS for efficient representation of band-limited signal.

• Bulletin of the Korean Chemical Society
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• v.26 no.6
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• pp.899-902
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• 2005

Indirect electrochemical oxidation of phenol by $Ce^{4+}$ was investigated in sulfuric acid solutions. It was found that electrode fouling during oxidation of phenol can be controlled by adjusting the time interval (TI) of double potential steps (DPSs). While the electroactivity was greatly decreased after several DPSs of a relatively long TI, repeated DPSs with a short potential pulse showed substantial amounts of electroactivity after a few hundreds or thousands DPS, suggesting that the formation of an insulating layer can be controlled by adjusting a potential program. Effectiveness of the consecutive application of DPSs for phenol decomposition was confirmed by GC-MS.