• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권6호
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• pp.636-643
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• 2000

Facial asymmetry is the most frequent disease in craniofacial deformities. And the primary causing area of that is mostly placing in mandible. That is to say, it is known that primarily, mandible grows excessively or deficiently, and other facial region involving maxilla undergoes compensatory growth secondarily, so asymmetric face develops. In facial asymmetry, the surgical correction of undergrowth is more difficult than that of overgrowth and the reason of it is the postoperative relapse caused by stress of surrounding soft tissues. It means the stress of surrounding soft tissues occurring after bone lengthening and reducing above stress is the same meaning with reducing postoperative relapse. Among various areas, mandibular ramus is the most difficult area to lengthen vertically and maintain its length. The reason of it is considered by many authors as the stress of surrounding pterygomasseteric sling which is enveloping lower border of mandible and interrupting elongation of ramal height. So we applied two different surgical procedures in which pterygomasseteric slings have different stress respectively to monkeys which have similar masticatory function and anatomy to human being and compared relapse by radiographic film and observed periodically the histochemical change of masseteric muscle fiber. So we could see the following results. The relapse was less in EVRO group in which we separated pterygomasseric sling in inferior border and didn't approximate muscle sling after vertical lengthening to minimize the stress of soft tissues than IVRO group in which we elongated ramal height preserving pterygomassetric sling. Of course, we could see a problem in EVRO group such as bone resorption in inferior border caused by uncovering the periosteum of inferior border. But we expect that such problem will be solved by developing periosteum substitutes for covering the exposed bone and minimizing the surgical trauma. In histochemical study of masseteric muscle fiber, the fiber constituents of EVRO group in which we minimized soft tissue stress was changed immediately after operation and maintained it for 1 year, whereas that of IVRO group in which we preserved soft tissue stress was changed in more portion after operation and recovered it by 1 year. By the histochemical results, we can see that the recovery of fiber constituents reflect the recovery of muscle stress and it is closely related with relapse phenomenon.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 F
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• pp.1989-1992
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• 1997

A new soft switching single stage AC-DC full bridge boost converter with unit input power factor and isolated output is presented. Due to using of the non-dissipative snubber in the primary side, a single stage high-power factor isolated full bridge boost converter has a significant reduction of switching losses in main switching devices and output rectifiers of the primary and secondary side, respectively. The non-dissipative snubber adopted in this study is consisted of a snubber capacitor C. and a snubber inductor $L_r$, a fast recovery snubber diode $D_r$, a commutation diode $D_p$. This paper presents the complete operating principles, theoretical analysis and simulation results.

• 한국농공학회논문집
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• 제47권5호
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• pp.51-61
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• 2005

In this study, borehole records were analyzed to verify the amplification of seismic motion at the soft reclaimed ground before and after the main event of the 1995 Hyogoken Nambu Earthquake at Port Island, Japan. From the analysis, it was shown that the amplification of seismic motion occurred near the soft ground surface (within 30 m below) where confining stress is low. Moreover, it was found that recovery of dynamic soil stiffness at the liquefied ground began gradually 3 hours after the liquefaction and completed in 10 days, when the ground exhibited the same seismic motion characteristics as those before the liquefaction.

• 한국자기공명학회논문지
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• 제5권1호
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• pp.19-28
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• 2001

Miscibility and morphology in blends of bisphenol-A type polycarbonate and poly (ester-ether) elastomer with different compositions are studied by solid-state NMR spectroscopy. $^{13}$ C Solid-state NMR of CP/MAS/TOSS/DD, CP/MAS/DD, inversion recovery CP/MAS/DD, and 2D rotor driven spin diffusion techniques are used to identify the miscibility, morphology, and transesterification in blends. The blends of PC /BT elastomer with 15% to 42% of soft segment seem to be single phase miscible mixing and those of PC/PBT and PC/PBT elastomer with 62% of soft segment are cocontinuous two phase immiscible mixing. No significant transesterification reactions are observed in blends with different compositions.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.493-496
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• 1999

A new soft switching single stage AC-DC full bridge boost converter with unit input power factor and isolated output is presented in this paper. Due to the use of a non-dissipative snubber on the primary side, a single stage high-power factor isolated full bridge boost converter has a significant reduction of switching losses in the main switching devices. The non-dissipative snubber adopted in this study consists of a snubber capacitor Cr, a snubber inductor Lr, a fast recovery snubber diode Dr, and a commutation diode Dr, and a commutation diode Dp. This paper presents the complete operating principles, theoretical analysis and experimental results.

• Journal of Mechanical Science and Technology
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• 제15권9호
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• pp.1281-1291
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• 2001

The hereditary integral form of a quasi-linear viscoelastic law has been employed. Four new concepts have been employed: 1. a reduced relaxation function with a non-linear exponential function of time, 2. an inverse method to determine the scale factor of the elastic response, 3. an instant elastic recovery strain during unloading, and 4. the results of a constitutive model for cyclic tests may be a function of the Heavyside class. These concepts have been supported by agreement between measured and predicted responses of soft connective tissue to three types of multiple cyclic tests which include rest periods of no extension and alternations between different strain levels. Such agreement has not been attained in the previous studies. Chun and Hubbard (2001) is our companion experimental analysis paper.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권4호
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• pp.407-418
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• 2014

As the high-throughput requirement in the next generation communication system increases, it becomes essential to implement high-throughput SISO (Soft-Input Soft-Output) decoder with minimal hardware resources. In this paper, we present the comparison results between cascaded radix-4 ACS (Add-Compare-Select) and LUT (Look-Up Table)-based radix-4 ACS in terms of delay, area, and power consumption. The hardware overhead incurred from the retiming technique used for high speed radix-4 ACS operation is also analyzed. According to the various analysis results, high-throughput radix-4 SISO decoding architecture based on simple path metric recovery circuit is proposed to minimize the hardware resources. The proposed architecture is implemented in 65 nm CMOS process and memory requirement and power consumption can be reduced up to 78% and 32%, respectively, while achieving high-throughput requirement.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.168-171
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• 2005

The conception of the passive lossless snubber with the simpler is presented. Thus a necessity condition of the passive lossless soft switching converter with the simplest topology is directed. A novel passive regenerative snubber called soft snubber applied to a hard switching converter is proposed. The passive snubber consists of a snubber inductor, two snubber rectifiers, and a snubber capacitor. The losses are reduced by inserting a snubber inductor in the series path of the rectifier during it's turn off. It is so simple that can make energy reset or capacitor discharged directly without producing any current circulation. To show the superiority of this converter is verified through the experiment with a 640W, 100kHz prototype converter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.1226-1228
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• 2004

A novel lossless passive snubber is proposed for soft switching the boost type converters. The proposed snubber does not use any auxiliary switches. but uses two identical snubber capacitors which are charged in parallel at turn off of the main switch and discharged in series at turn on automatically, and the discharged energy is recovered effectively (more than $95[\%]$ recovery) into the output capacitor. Thus, the snubber provides zero voltage switching for the converter main switch, reducing both the turn off losses and the electromagnetic interference(EMI) noise, whitch improves the converter performance. The experimental results of a 20[kHz] 600[W] DC-DC boost converter and a single-phase AC-DC boost rectifier with the new snubber are presented.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 추계학술대회 논문집
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• pp.133-136
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• 2002

This paper presents m improved soft switching Buck converter using an energy recovery snubber which is composed of a tapped inductor, two snubber capacitors and three snubber diodes. The proposed Buck converter achieves zero voltage turn-of in the main power switch md freewheeling diode. The operating Principle of the Proposed Buck converter is described through the simulation, relevant equation and analysis.