• Archives of Reconstructive Microsurgery
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• v.22 no.1
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• pp.38-41
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• 2013

A 31-year-old female patient presented with a skin and soft tissue defect measuring $8{\times}6cm$ in size with exposure of the extensor hallucis longus tendon and the first metatarsal bone after metatarsal lengthening for brachymetatarsia. The defect was covered with a distally based dorsalis pedis flap based on the distal communicating branch of the dorsalis pedis artery. Secondary defect was covered by a split thickness skin graft. There was congestion of the flap tip after the operation; however, it was resolved using medical leeches and anti-coagulants. No necrosis or infection was encountered and the contour of the flap was satisfactory. There was no donor site morbidity. Reverse dorsalis pedis flap has not been commonly used due to the anatomical variation and uncertainty, which is different from the reverse radial forearm flap. However, when faced with the challenge of a moderate soft tissue defect of the distal forefoot, we believe that the reverse dorsalis pedis flap offers a good option with various advantages.

• International Journal of Control, Automation, and Systems
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• v.4 no.5
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• pp.601-614
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• 2006

In this paper, a study on task assignment strategies for a complex real-time network system is presented. Firstly, two task assignment strategies are proposed to improve previous strategies. The proposed strategies assign tasks with meeting end-to-end real-time constraints, and also with optimizing system utilization through period modulation of the tasks. Consequently, the strategies aim at the optimizationto optimize of system performance with while still meeting real-time constraints. The proposed task assignment strategies are devised using the genetic algorithmswith heuristic real-time constraints in the generation of new populations. The strategies are differentiated by the optimization method of the two objectives-meeting end-to-end real-time constraints and optimizing system utilization: the first one has sequential genetic algorithm routines for the objectives, and the second one has one multiple objective genetic algorithm routine to find a Pareto solution. Secondly, the performances of the proposed strategies and a well-known existing task assignment strategy using the BnB(Branch and Bound) optimization are compared with one other through some simulation tests. Through the comparison of the simulation results, the most adequate task assignment strategies are proposed for some as system requirements-: the optimization of system utilization, the maximization of running tasktasks, and the minimization of the number of network node nodesnumber for a network system.

• Smart Structures and Systems
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• v.22 no.4
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• pp.469-479
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• 2018

The present research study utilizes a multi-objective optimization method for Pareto optimization of an eight-degree of freedom full vehicle vibration model, adopting a non-dominated sorting genetic algorithm II (NSGA-II). In this research, a full set of ride comfort as well as ride safety parameters are considered as objective functions. These objective functions are divided in to two groups (ride comfort group and ride safety group) where the ones in one group are in conflict with those in the other. Also, in this research, a special optimizing technique and combinational method consisting of weighted sum method and Pareto optimization are applied to transform Pareto double-objective optimization to Pareto full-objective optimization which can simultaneously minimize all objectives. Using this technique, the full set of ride parameters of three dimensional vehicle model are minimizing simultaneously. In derived Pareto front, unique trade-off design points can selected which are non-dominated solutions of optimizing the weighted sum comfort parameters versus weighted sum safety parameters. The comparison of the obtained results with those reported in the literature, demonstrates the distinction and comprehensiveness of the results arrived in the present study.

• Structural Engineering and Mechanics
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• v.74 no.2
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• pp.297-311
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• 2020

The main purpose of this study is to analyze the effects of external pressure on the vibration and buckling of functionally graded (FG) spherical panels resting of elastic medium. The material characteristics of the FG sphere continuously vary through the thickness direction based on the power-law rule. In accordance with first-order shear deformation shell theory and by the use of Ritz formulation the governing equations are presented. In this regard, the beam functions are applied in two-dimensions for different sets of boundary supports. The Winkler and Pasternak models of elastic foundations are also taken into account. In order to show the validity and applicability of the presented formulation, various comparison studies are given. Furthermore, a diverse range of numerical results is reported to check the impacts of geometrical and material parameters along with external pressure on the vibration and buckling analysis of FG spherical panels.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.2070-2075
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• 2004

Performance of a solid oxide fuel cell (SOFC) can be enhanced by converting thermal energy of its high temperature exhaust gas to mechanical power using a micro gas turbine (MGT). A MGT plays also an important role to pressurize and warm up inlet gas streams of the SOFC. In this study, the influence of performance characteristics of the tubular SOFC on the hybrid power system is discussed. For this purpose, detailed heat and mass transfer with reforming and electrochemical reactions in the SOFC are mathematically modeled, and their results are reflected to the performance analysis. The analysis target is 220kWe SOFC/MGT hybrid system based on the tubular SOFC developed by Siemens-Westinghouse. Special attention is paid to the ohmic losses in the tubular SOFC counting not only current flow in radial direction, but also current flow in circumferential direction through the anode and cathode.

• Journal of the Korean Institute of Oriental Medical Informatics
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• v.13 no.1
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• pp.1-13
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• 2007

Korean medicine industry general means all industry activities related to Korean medicine. It covers material resources such as herbs and products made herbs, medical instruments, Korean medical servics and related information service based on Korean medicine theories. Also according to industrial strategy, Korean medicine industry was to define and branch. The industrial strategy of Korean medicine industry was based on kowledge, high-end, intensive techology, and global denand. By the industrial strategy of Korean Medicine industry, a study on the optimal industry construction of Korean medicine industry was standardizaition in the basic research and promoted bouds, efficiency in the group industrial, detention of global fund and global technology, and intenational division of product process. It is the optimal industry construction of Korean medicine industry by the industrial strategy of Korean medicine industry. At once adjustment to the optimal industry construction of Korean medicine industry by the industrial strategy of Korean medicine industry was internationalization in the positive adjustment.

• Journal of Power Electronics
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• v.13 no.6
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• pp.1058-1069
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• 2013

This paper proposes and designs a new output filter called an LCFL filter for application to three phase three wire shunt active power filters (SAPF). This LCFL filter is derived from a traditional LCL filter by replacing its capacitor with a C-type filter, and then constructing an L-C-type Filter-L (LCFL) topology. The LCFL filter can provide better switching ripple attenuation capability than traditional passive damped LCL filters. The LC branch series resonant frequency of the LCFL filter is set at the switching frequency, which can bypass most of the switching harmonic current generated by a SAPF converter. As a result, the power losses in the damping resistor of the LCFL filter can be reduced when compared to traditional passive damped LCL filters. The principle and parameter design of the LCFL filter are presented in this paper, as well as a comparison to traditional passive damped LCL filters. Simulation and experimental results are presented to validate the theoretical analyses and effectiveness of the LCFL filter.

• Archives of Plastic Surgery
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• v.47 no.1
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• pp.97-101
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• 2020

Although the success rate of deep inferior epigastric perforator (DIEP) flaps has increased, late flap failures still occur and have a low salvage rate. The present article describes a case of salvage of a case of late flap failure using the pedicle vein as a vein graft source. A 50-yearold woman underwent a bilateral DIEP free flap procedure. On postoperative day 6, she experienced flap compromise and underwent emergency flap revision. In the flap revision, flap venous drainage and the superficial inferior epigastric vein were completely obstructed. A Fogarty catheter was used to remove a thrombus from the completely obstructed pedicle vein, and this pedicle vein was used as a graft source and was ligated in retrograde fashion to the flap vein stump. After injection of urokinase into the arterial branch, venous flow to the flap was restored. At a 6-month follow-up visit in the outpatient clinic, only partial fat necrosis at the flap was noted. By dissecting various perforators in the initial operation, decisions regarding immediate revision can be made with more confidence. Additionally, the combined procedures performed in this case may be helpful even for practitioners treating cases of late flap compromise.

• Archives of Reconstructive Microsurgery
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• v.7 no.1
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• pp.10-14
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• 1998

When covering a skin defect of the finger with a local flap is difficult, a vascular island flap is often used. For a palmar skin defect, it is desirable to add a sensory supply to the flap. This report describes a neurovascular island flap that was used to repair a palmar skin defect, the donor skin coming from the dorsal region of the middle phalanx. This flap is elevated with a vascular pedicle of the palmar digital artery and its dorsal skin branch, including the dorsal digital veins, palmar digital nerve and its cutaneous branches. The advantage of this flap are that it can be transferred with ease and without any tension. No special manipulation is required under a microscope and operation can be performed under a simple nerve-block. There if little possibility that the flap itself undergoes ischemic change or congestion. The disadvantage of this flap are that a skin graft is required at the donor skin site and one palmar digital aretery is lost. We think that this neurovascular island flap is one of the useful methods for skin defects that are difficult to cover with a local flap.

• Steel and Composite Structures
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• v.35 no.2
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• pp.295-306
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• 2020

This paper deals with free vibration analysis of non-uniform column resting on elastic foundations and subjected to follower force at its free end. The internal pores and graphene platelets (GPLs) are distributed in the matrix according to different patterns. The model is proposed with material parameters varying in the thickness of column to achieve graded distributions in both porosity and nanofillers. The elastic modulus of the nanocomposite is obtained by using Halpin-Tsai micromechanics model. The differential quadrature method as an efficient and accurate numerical approach is used to discretize the governing equations and to implement the boundary conditions. It is observed that the maximum vibration frequency obtained in the case of symmetric porosity and GPL distribution, while the minimum vibration frequency is obtained using uniform porosity distribution. Results show that for better understanding of mechanical behavior of nanocomposite column, it is crucial to consider porosities inside the material structure.