• Journal of Power Electronics
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• v.9 no.5
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• pp.708-717
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• 2009

In this paper a new zero voltage transition PWM bridgeless PFC is introduced. The auxiliary circuit provides soft switching condition for all semiconductor devices. Also, in the resonant path of the auxiliary circuit, only two semiconductor devices exist. Therefore the resonant conduction losses are low. Furthermore, the auxiliary circuit semiconductor elements consist of only one diode and one switch. The proposed auxiliary circuit is applied to a bridgeless PFC converter to further reduce conduction and switching losses. In this paper, the operating modes of this converter are explained and the resulting ideal and simulation waveforms are shown. The presented experimental results justify the theoretical analysis.

• Geomechanics and Engineering
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• v.6 no.4
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• pp.377-389
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• 2014

The vacuum consolidation method which was proposed by Kjellman in 1952 has been studied extensively and used successfully since early 1980 throughout the world, especially in East and Southeast Asia. Despite the increased successful use, different opinions still exist, especially in connection to distribution of vacuum with depth and time in vertical drains and in soil during preloading of soft ground. Porewater pressure measurements from actual cases of field vacuum and vacuum-fill preloading as well as laboratory studies have been examined. It is concluded that (a) a vacuum magnitude equal to that in the drainage blanket remains constant with depth and time within the vertical drains, (b) as expected, vacuum does not develop at the same rate within the soil at different depths; however, under ideal conditions vacuum is expected to become constant with depth in soil after the end of primary consolidation, and (c) there exists a possibility of internal leakage in vacuum intensity at some sublayers of a soft clay and silt deposit. A case history of vacuum loading with sufficient subsurface information is analyzed using the ILLICON procedure.

• Ocean Systems Engineering
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• v.7 no.2
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• pp.75-87
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• 2017

A breakwater has always been an ideal option to prevent shoreline erosion due to wave action as well as to maintain the tranquility in the lagoon area. The effects of the impinging wave on the structure could be analyzed and evaluated by several physical and numerical methods. An alternate approach to the numerical methods in the prediction of performance of a breakwater is Artificial Intelligence (AI) tools. In the recent decade many researchers have implemented several Artificial Intelligence (AI) tools in the prediction of performance, stability number and scour of breakwaters. This paper is a comprehensive review which serves as a guide to the current state of the art knowledge in application of soft computing techniques in breakwaters. This study aims to provide a detailed review of different soft computing techniques used in the prediction of performance of different breakwaters considering various combinations of input and response variables.

• International Journal of Oral Biology
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• v.46 no.4
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• pp.200-207
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• 2021

In case of gingival recession and alveolar bone defects due to tooth loss for a long period of time in a single tooth in the maxillary anterior region, it is not easy to obtain aesthetic results with a single implant prosthesis. For aesthetic restoration, it is important to preserve hard and soft tissues through alveolar bone augmentation as well as restore harmony with adjacent teeth and soft tissues by placing the implant in an ideal location. In this case, an implant was placed using guided bone regeneration and a connective tissue graft simultaneously with immediate implantation after extraction from the maxillary anterior region where only residual root was left for a long period of time.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.6A
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• pp.611-616
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• 2006

In this paper, we propose a practical implementation method of a soft bit decision expression for an R-QAM (Gray coded Rectangular Quadrature Amplitude Modulation) signal based on the Max-Log-MAP algorithm. The parameters of the soft decision expression for the practical implementation can be obtained with simple arithmetic functions associated with some deterministic parameters such as a received value, distances between symbols, and the order of modulation on a signal space. Also, we analyze the performance of an iterative decoding scheme for the QAM signal with I/Q phase unbalance. The unbalance results from the non-ideal characteristic of components such as a phase shifter between in-phase and quadrature paths for quadrature modulator/demondulator.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.4
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• pp.347-358
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• 2013

When analyzing soft tissue of the profile, Subnasale is often used as an important reference point. But there are few studies on the ideal position of the Subnasale. Therefore, the purpose of this study is to present an objective reference of the esthetic face relating to the change of Subnasale position in Koreans' profile, and also to determine whether there is concordance between professionals and laypersons in their perception of facial attractiveness. The one determined as appropriate profile portion by experts of pictures taken in women in 20s was selected. The photograph was modified changing the Subnasale anteroposteriorly on the plane perpendicular to the true vertical line, while maintaining the nasolabial angle. The photographs were presented to a group of professionals (9 orthodontists) and 126 laypersons, who were asked to assess the facial attractiveness of the photographs on a VAS independently. The conclusion was obtained. 1. The ideal position of the Subnasale is when the ratio of the distance Lateral canthus~Subnasale : Subnasale~Pronasale is 1.769 : 1. 2. The ideal degrees between the true vertical line passing through Nasion and Subnasale is $5.5^{\circ}$ 3. The professionals recognized every change in the ratio, but the laypersons couldn't differentiate between the change from 1.571 : 1 to 1.769 : 1.

• Archives of Plastic Surgery
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• v.34 no.6
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• pp.759-764
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• 2007

Purpose: Various types of flaps, with their own advantages and disadvantages, have been described for reconstruction of soft tissue defect with exposure of tendons, bones, or joints in the hand or foot. Local flaps with random vascularity have a limitation by their length. Free flaps are time-consuming procedure that may require the sacrifice of some major vessels. The ideal flap for covering soft tissue defects of the hand or foot must provide subcutaneous tissue that tendons can glide through which, supply enough subcutaneous tissue for cover of vital neural, bony, vascular and joint structures, and it has to be aesthetically pleasing. The adipofascial flap fulfills these criteria. It allows immediate or early closure of difficult wound of hand and foot in an easy way, and is especially indicated for small to medium-sized defects. Methods: From October 2005 to December 2006, seven cases underwent this procedure to reconstruct soft tissue defect on hand or foot. Results: All flaps survived completely, and no complications were observed. Conclusion: The adipofascial flap is a convenient flap for coverage of soft tissue with exposure of vital structure in the hand or foot, and provide several advantages, as following; easy and safe, short operating time, one stage procedure, thinness and good pliability of the flap, preservation of the major vascular pedicles, skin preservation at the donor site, thus preserve the shape of the limb and minimize donor site scar.

• Journal of Periodontal and Implant Science
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• v.48 no.5
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• pp.274-283
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• 2018

Purpose: Numerous indices have been proposed to analyse wound healing in oral soft tissues, but each has specific shortcomings. A new method of analysis, the Early Wound Healing Score (EHS), was evaluated in the present study. The aim was to assess more accurately early healing by primary intention of surgical incisions in periodontal soft tissues. Methods: Twenty-one patients were treated with different surgical procedures comprising 1 or 2 vertical releasing incisions as part of a surgical access flap. Twenty-four hours after surgery, early wound healing at the vertical releasing incisions was assessed using the EHS. This score assessed clinical signs of re-epithelialization (CSR), clinical signs of haemostasis (CSH), and clinical signs of inflammation (CSI). Since complete wound epithelialization was the main outcome, the CSR score was weighted to be 60% of the total final score. Accordingly, a score of 0, 3, or 6 points was possible for the assessment of CSR, whereas scores of 0, 1, or 2 points were possible for CSH and CSI. Higher values indicated better healing. Accordingly, the score for ideal early wound healing was 10. Results: Thirty vertical releasing incisions were assessed in 21 patients. At 24 hours after incision, 16 vertical releasing incisions (53.33%) received the maximum score of CSR, while 6 cases (20%) received an EHS of 10. None of the cases received 0 points. Conclusion: The EHS system may be a useful tool for assessing early wound healing in periodontal soft tissue by primary intention after surgery.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.4
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• pp.354-359
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• 2018

In a single implant restoration of maxillary anterior teeth, it is difficult to accomplish an aesthetic restoration of the implant prosthesis in the case of gingival recession and bone defect problems. To maintain aesthetic stability in the long term, it is important to place the implant in the ideal position as well as the recovery of the soft tissue and harmony with the prosthesis. Not only ideal implant position but also the harmony with surrounding soft tissues are important to fabricate aesthetic implant prosthesis for these cases. for these cases, a 47- years -old male with lowered level of osseous crest and gingival recession on maxillary anterior tooth was treated with guided bone regeneration and gingival recontouring.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.428-434
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• 2005

Extensive and complicated defects on the body call for an omnipotent tool for a perfect reconstruction. Flaps derived from the omentum has many advantages over the conventional flaps. From 1999 to 2004, Omental flaps were applied for various soft tissue reconstructions. Among total 20 total 7 cases were for immediate reconstruction, 2 cases for chronic infection, 3 cases for simultaneous reconstruction of two defects, 4 cases for functional joint reconstruction and 4 cases were for flow- through revascularization. Among these cases, 3 cases were operated with minimal incision harvest technique. There were no complete flap failures, partial necrosis of the distal parts were noted on three cases. The omental flap is indicated on a large contaminated defect reconstruction due to its large size, well-vascularized, and malleable properties. The omental flap provides several additional advantages over other flaps, which are; the availability of the one staged simultaneous reconstruction of two defects with one flap, providing gliding function for the joint motion, and a flow-through characteristics with long vascular pedicle. But there are some serious shortcomings, including a long abdominal scar and intraabdominal problems. However, these are rare and can be minimized with our minimal incision technique. Due to its unique characteristics. the omentum is one of the ideal tissues for the reconstruction of the complicated soft tissue defects due to its unique characteristics.