• Ocean and Polar Research
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• v.25 no.spc3
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• pp.385-392
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• 2003

A new type of soft ground breakwater was recently developed, which does not need ground improvement because of light weight and structural characteristics. The various studies about consolidation settlements and lateral behavior of proposed soft ground breakwater have been conducted. But, the systematic investigations on the construction performance and long-term settlements of new type breakwater has not been accomplished. In this study, construction simulation of soft ground breakwater with soil box model test and experiments of the long-term wave loaded breakwater were performed. The results of test shows that it is possible to compensate differential settlements by dead loading and/or suction pressure, and to reduce the consolidation settlements by preloading method. It was also found that the vertical and lateral displacements of long-term wave loaded breakwater were negligible.

• Archives of Reconstructive Microsurgery
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• v.18 no.1
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• pp.16-22
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• 2009

The purpose of this study was to present the clinical result of anterolateral thigh free flap for pretibial soft tissue lesion after chronic tibia osteomyelitis. From December 2006 to September 2008, Five patients were included in our study. 4 of 5 were superficial or localized types of chronic tibia osteomyelitis, based on the classification of Cierny and Mader. Average age at the surgery was 45 years, three were males and two were females. All had a history of chronic tibia osteomyelitis and subsequent pretbial soft tissue lesions coming from previous operations or pus drainage. Pretibial soft tissue defects included small ulcers, fibrotic, bruisable soft tissue and small bony exposures, but not large-sized bony exposures nor active pus discharge. After complete debridement of large sized pretibial soft tissue lesions and decortication of anterior tibial cortical dead bone, anterolateral thigh free flap was applied to cover remained large pretibial soft tissue defect and to prevent the recurrence of infection. All flaps survived and provided satisfactory coverage of soft tissue defect on pretibial region for 16 months' mean follow up period. No patients has had recurrence of osteomyelitis. Anterolateral thigh free flap could be recommend for large sized pretibial soft tissue defect of supreficial or localized types of chronic tibia osteomyelitis after through debridement.

• Archives of Reconstructive Microsurgery
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• v.16 no.2
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• pp.86-92
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• 2007

Failure of reattachment of finger is inevitable in replantation surgery and that failure rate is about 10 % are reported in many authors. Management of the failed finger replantation is challenge to microsurgeons. We report 7 cases of thumb reconstruction after failure of replantation. The reconstructive surgery composed with early debridement of soft tissue that are under gangrenous processing, extract the phalangeal bone without any soft tissues. Osteosynthesis of the extracted phalangeal bone with host phalangeal bone. The exposed bony portion covered with vascularized flaps such as reverse radial forearm pedicled flap, free radial forearm flap and neurovascular island finger flap. This procedure underwent within a week after vascular insufficiency developed. All of the flaps are survived, bone union achieved within 3 months. The function and external appearance of the reconstructed thumb were encouraging; pinch power was average 1.2 pounds. Early removal of necrotizing soft tissue followed by covering none vascular phalangeal bone which extracted from the dead phalanx with vascularized flap is one of the useful alterative solutions in failed replantation surgery in hand.

• Journal of Power Electronics
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• v.11 no.5
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• pp.662-668
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• 2011

This paper presents an analysis of a 4th order LCLC resonant converter with a capacitive output filter using the state-space approach. The analysis of the converter shows that there are four intervals in a half period. In each interval, the state-space equations are obtained. Due to the soft switching of the converter, an exact equation for the Zero Voltage Switching (ZVS) time and the maximum dead time of the inverter switches are presented. The simulation and experimental results obtained from a 10kv, 370w prototype confirm the validity of the theoretical analysis.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.3
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• pp.348-352
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• 1996

Soft tissue defects in oral & maxillofacial region caused by tumor resection, trauma, congenital deformities have been treated in autogenous soft tissue flap, allogenic material, free dermal graft, fascia graft. Of these methods, autogenous dermis graft had initially been applied in hernia treatment at the beginning of nineteenth century and have been applied in soft tissue augmentation coverage of vital structure, dead space removal and reconstruction of fascia. A fat graft is used in reconstruction of orbit at the enucleation, restoration of facial contours, etc. In this case, patient with chin soft tissue defect in traffic accident was treated in autogenous dermis-fat graft from patient's abdominal and gluteal region. Chin defect was reconstructed favorably. There was no severe atrophy of grafted area 12 months postoperatively. We will report the result that is favorable esthetically with literature review.

• Geomechanics and Engineering
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• v.5 no.3
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• pp.195-221
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• 2013

A centrifuge model study is carried out to investigate the behavior of pile subject to negative skin friction induced by pile installation, ground water drawdown and surcharge loading. A single end-bearing pile is examined as the induced negative skin friction would induce the most severe stress on the pile structural material as compared to friction piles. In addition, the behavior of the pile under simultaneous negative skin friction and dead/live loads is examined. To facilitate detailed interpretations of the test results, the model setup is extensively instrumented and involves elaborate test control schemes. To further examine the phenomenon of negative skin friction on an end-bearing pile, finite element analyses were conducted. The numerical analysis is first validated against the centrifuge test data and subsequently extended to examine the effects of pile slenderness ratio, surcharge intensity and pile-soil stiffness ratio on the degree of mobilization of negative skin friction induced on the pile. Finally experimental and numerical studies are conducted to examine the effect of applied transient live load on pile subject to negative skin friction.

• Journal of Trauma and Injury
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• v.20 no.2
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• pp.119-124
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• 2007

Purpose: Management of the soft tissue defect in the lower extremity caused by trauma has always been difficult. Coverage with local and free muscle flaps after complete surgical excision of necrotic soft tissue and bone is a major strategy for treatment. There is no doubt that muscle provides a good blood supply, thus improving bone healing and increasing resistance to bacterial inoculation. However, accompanying problems are seen in cases with shallow dead space. This research was conducted to assess the efficacy of raising anterolateral thigh flaps and transferring them to the defect after complete debridement of non-viable, infected, and scar tissue as an alternative way to use local or free muscle flaps. Methods: From March 2005 to October 2007, 18 cases of soft tissue defect on lower extremities were re-surfaced with an anterolateral thigh perforator free flap. Results: The follow-up period ranged from 1 to 31 months with a mean of 15.9 months. All flaps survived completely. Satisfactory aesthetic and functional results were achieved. Under a two-point discrimination test, 13 patients had sensory recovery from 11 mm to 20 mm after 6 months postoperatively. Conclusion: Reconstruction of the lower extremity with anterolateral thigh perforator free flaps after appropriate debridement is a good alternative way to use local or free muscle flaps.

• Journal of the Korean Arthroscopy Society
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• v.6 no.2
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• pp.192-194
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• 2002

The goal of surgery of chronic osteomyelitis is removal of dead bone and achieving a viable and vascular environment. During saucerization, the sequestrum could be checked and resected completely. But it can causes vascular injury by massive soft tissue dissection in saucerization of chronic osteomyelitis. Recently, we experienced medulloscopy in the treatment of chronic osteomyelitis and it is possible for us to visualize the sequestrum, to do complete resection of dead bone and to reduce vascular injury during operation.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.6
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• pp.25-32
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• 2011

This paper proposes high efficiency current-mode DC-DC buck converter that are suitable for portable devices. The current-mode DC-DC buck converter using adjustable Dead-time control method improves the power efficiency 2~5%. The buck converter has been implemented with a standard 0.35${\mu}m$ CMOS process. The size of this chip is 0.97$mm^2$. The input range of the fabricated DC-DC buck converter is 2.5V~3.3V, and the output is 1.8V. The maximum loading current of the converter is 500mA and the peak efficiency is 93% at 200mA loads.

• Journal of Power Electronics
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• v.18 no.4
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• pp.975-984
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• 2018

This work presents a high efficiency phase shifted full bridge (PSFB) DC-DC converter for use in the second stage of a battery charger for neighborhood electrical vehicle (EV) applications. In the design of the converter, Lithium-ion battery cells are preferred due to their high voltage and current rates, which provide a high power density. This requires wide range output voltage regulation for PSFB converter operation. In addition, the battery charger works with a light load when the battery charge voltage reaches its maximum value. The soft switching of the PSFB converter depends on the dead time optimization and load condition. As a result, the converter has to work with soft switching at a wide range output voltage and under light conditions to reach high efficiency. The operation principles of the PSFB converter for the continuous current mode (CCM) and the discontinuous current mode (DCM) are defined. The performance of the PSFB converter is analyzed in detail based on wide range output voltage and load conditions in terms of high efficiency. In order to validate performance analysis, a prototype is built with 42-54 V / 15 A output values at a 200 kHz switching frequency. The measured maximum efficiency values are obtained as 94.4% and 76.6% at full and at 2% load conditions, respectively.