• Title/Summary/Keyword: transfer free

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Free Tissue Transfer in Sickle Cell Disease: A Case Report and Systematic Review

  • Anne Huang;Ronak A. Patel;Lawrence J. Gottlieb
    • Archives of Plastic Surgery
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    • v.50 no.3
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    • pp.315-324
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    • 2023
  • Hemoglobinopathies such as sickle cell disease (SCD) are traditionally considered a relative contraindication to free tissue transfer, due to concerns that erythrocyte sickling will increase the risk of microvascular thrombosis and flap failure. This article describes a case report with the successful use of free tissue transfer in a patient with SCD and provides a systematic literature review on free tissue transfer in SCD. A retrospective chart review was performed of a patient with SCD who underwent free tissue transfer at the authors' institution. A systematic literature review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed using the keywords "free tissue transfer," "free flap," or "microsurgery" and "sickle cell" on PubMed, Ovid/Medline, and Scopus. A 29-year-old male with delayed presentation of an electrical burn to the face and scalp underwent wound closure with a free anterolateral thigh flap. Key management principles included red blood cell transfusion to keep hemoglobin S under 30% and hemoglobin greater than 10 g/dL, maintenance of hydration, normothermia, adequate analgesia, and postoperative anticoagulation. Systematic literature review identified 7 articles describing 13 cases of free tissue transfer in 10 patients with SCD, with combined complete free flap success in 10 of the 13 flaps. Free tissue transfer can be successfully performed in patients with SCD. However, evidence on the optimal management of this unique patient population in the perioperative period after free tissue transfer is limited to case reports in the literature.

Free Vibration Analysis of Double Cylindrical Shells Using Transfer of Influence Coefficent (영향계수의 전달에 의한 2중 원통형 셸의 자유진동해석)

  • Choi, Myung-Soo;Yeo, Dong-Jun
    • Journal of Power System Engineering
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    • v.21 no.5
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    • pp.48-54
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    • 2017
  • The transfer influence coefficient method which is an vibration analysis algorithm based on the transfer of influence coefficient is applied to the free vibration analysis of double cylindrical shells. After the computational programs for the free vibration analysis of double cylindrical shells were made using the transfer influence coefficient method and the transfer matrix method, we compared the results using the transfer influence coefficient method with those by the transfer matrix method. The transfer influence coefficient method provided the good computational results in the free vibration analysis of double cylindrical shells. In particular, The results of the transfer influence coefficient method are superior to those of the transfer matrix method when the stiffness of internal springs connecting a inside cylindrical shell and a outside cylindrical shell is very large.

Free Vibration Analysis of Timoshenko Arcs with Elastic Supports Using Transfer of Influence Coefficient (영향계수의 전달을 이용한 탄성 지지된 티모센코 호의 자유진동 해석)

  • Choi, Myung-Soo;Yeo, Dong-Jun
    • Journal of Power System Engineering
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    • v.21 no.2
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    • pp.70-76
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    • 2017
  • When Timoshenko arcs considering the shear deformation and rotatory inertia have elastic supports, the authors analyze in-plane free vibration of them by the transfer influence coefficient method. This method finds the natural frequencies of them using the transfer of influence coefficient after obtaining the transfer matrix of arc element from numerical integration of the differential equations governing the vibration of arc. In this study, two computer programs were made by the transfer influence coefficient method and the transfer matrix method for analyzing free vibration of Timoshenko arcs. From numerical results of four computational models, we confirmed that the transfer influence coefficient method is a reliable method when analyzing the free vibration of Timoshenko arcs. In particular, the transfer influence coefficient method is a effective method when analyzing the free vibration of arcs with rigid supports.

Free Tissue Transfer in the Treatment of Infected Diabetic Foot Ulcers (유리 조직 이식술을 이용한 당뇨병성 족부 궤양의 치료)

  • Song, June-Young;Kim, Ki-Soo;Kim, Hee-Dong;Park, In-Suk
    • Archives of Reconstructive Microsurgery
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    • v.10 no.2
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    • pp.154-162
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    • 2001
  • Diabetic foot ulcer is a serious complication which result from long-standing diabetes. Especially, severe infected diabetic foot ulcer results in unwanted lower extremity amputation. The diabetic patient is considered the relative contraindication for microsurgery because of the severe peripheral vascular disease. Recently, microvascular free tissue transfer technique applied to diabetic foot ulcer. It is well known that free tissue transfer provides immediate soft tissue coverage and control of infection. So it is possible that preservation of the lower extremity through free tissue transfer. A retrospective study of diabetic patients who had infected foot ulcer from 1999 to 2000 with foot defects reconstructed with free tissue transfer were reviewed. Thirteen patients were studied with mean follow-up of 12.7 months. There were two deaths during follow-up period. There were two failures after free flap surgery. All eleven survived patients were ambulatory. There was no recurrence of ulcer. No patient need amputation above the ankle joint. We have found that free tissue transfer for infected diabetic foot ulcer is very effective surgical technique. Careful patient selection and regular follow-up is important.

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A Study for Increasing Satisfaction of Transfer Facilities, Services & Transit Tour by Analyzing Air Passengers' Behaviors (항공여객 특성분석을 통한 환승시설·서비스 및 환승투어 만족도 제고 연구)

  • Kim, Kwang-Ok;Kim, Kee-Woong;Kim, Kwang-Il;Kim, Nam-Sun;Park, Sung-Sik
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.23 no.2
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    • pp.89-97
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    • 2015
  • The volume of transfer passengers now faces a crisis because the number of Chinese and Japanese passengers, the majority of transfer through Korea, is decreasing. This paper is analyzing the their air travel behaviors as well as characteristics of their transfer behaviors at airport. According to the research, it is suggested that transfer passengers perceive the importance of duty-free stores but their satisfaction of using duty-free stores during their transfer at Icheon airport was proven to be low. Considering the characteristics of transfer service quality at Incheon airport, waiting time of transfer is important but not satisfactory for them. Moreover, information of free transfer tour to city downtown and paid-in transfer tour for medical tourism is not known very well among North East Asian passengers. Thus, it is necessary to do detailed research of North East Asian transfer passengers, who have transferred through Incheon airport more than twice a year, to find out their exact needs of transfer tour in Korea.

Free Vibration Analysis of Plate Structures Using Finite Element-Transfer Stiffness Coefficient Method

  • Park, Myung-Soo
    • Journal of Mechanical Science and Technology
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    • v.17 no.6
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    • pp.805-815
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    • 2003
  • In order to execute efficiently the free vibration analysis of 2-dimensional structures like plate structures, the author developed the finite element-transfer stiffness coefficient method. This method is based on the combination of the modeling techniques in the FEM and the transfer technique of the stiffness coefficient in the transfer stiffness coefficient method. Numerical results of the simply supported and the elastic supported rectangular plates showed that the present method can be successfully applied to the free vibration analysis of plate structures on a personal computer. We confirmed that, in the case of analyzing the free vibration of rectangular plate structures, the present method is superior to the FEM from the viewpoint of computation time and storage.

Free Vibration Analysis of Curved Beams Regarded as Discrete System Using Finite Element-Transfer Stiffness Coefficient Method (유한요소-전달강성계수법에 의한 이산계 곡선보의 자유진동해석)

  • Choi, Myung-Soo;Yeo, Dong-Jun
    • Journal of Power System Engineering
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    • v.21 no.1
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    • pp.37-42
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    • 2017
  • A curved beam is one of the basic and important structural elements in structural design. In this paper, the authors formulated the computational algorithm for analyzing the free vibration of curved beams using the finite element-transfer stiffness coefficient method. The concept of the finite element-transfer stiffness coefficient method is the combination of the modeling technique of the finite element method and the transfer technique of the transfer stiffness coefficient method. And, we confirm the effectiveness the finite element-transfer stiffness coefficient method from the free vibration analysis of two numerical models which are a semicircle beam and a quarter circle beam.

Free Vibration Analysis of Axisymmetric Conical Shell

  • Choi, Myung-Soo;Yeo, Dong-Jun;Kondou, Takahiro
    • Journal of Power System Engineering
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    • v.20 no.2
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    • pp.5-16
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    • 2016
  • Generally, methods using transfer techniques, like the transfer matrix method and the transfer stiffness coefficient method, find natural frequencies using the sign change of frequency determinants in searching frequency region. However, these methods may omit some natural frequencies when the initial frequency interval is large. The Sylvester-transfer stiffness coefficient method ("S-TSCM") can always obtain all natural frequencies in the searching frequency region even though the initial frequency interval is large. Because the S-TSCM obtain natural frequencies using the number of natural frequencies existing under a searching frequency. In this paper, the algorithm for the free vibration analysis of axisymmetric conical shells was formulated with S-TSCM. The effectiveness of S-TSCM was verified by comparing numerical results of S-TSCM with those of other methods when analyzing free vibration in two computational models: a truncated conical shell and a complete (not truncated) conical shell.

Effects of Combustor-Level High Inlet Turbulence on the Endwall Flow and Heat/Mass Transfer of a High-Turning Turbine Rotor Cascade

  • Lee, Sang-Woo;Jun, Sang-Bae;Park, Byung-Kyu;Lee, Joon-Sik
    • Journal of Mechanical Science and Technology
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    • v.18 no.8
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    • pp.1435-1450
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    • 2004
  • Experimental data are presented which describe the effects of a combustor-level high free-stream turbulence on the near-wall flow structure and heat/mass transfer on the endwall of a linear high-turning turbine rotor cascade. The end wall flow structure is visualized by employing the partial- and total-coverage oil-film technique, and heat/mass transfer rate is measured by the naphthalene sublimation method. A turbulence generator is designed to provide a highly-turbulent flow which has free-stream turbulence intensity and integral length scale of 14.7% and 80mm, respectively, at the cascade entrance. The surface flow visualizations show that the high free-stream turbulence has little effect on the attachment line, but alters the separation line noticeably. Under high free-stream turbulence, the incoming near-wall flow upstream of the adjacent separation lines collides more obliquely with the suction surface. A weaker lift-up force arising from this more oblique collision results in the narrower suction-side corner vortex area in the high turbulence case. The high free-stream turbulence enhances the heat/mass transfer in the central area of the turbine passage, but only a slight augmentation is found in the end wall regions adjacent to the leading and trailing edges. Therefore, the high free-stream turbulence makes the end wall heat load more uniform. It is also observed that the heat/mass transfers along the locus of the pressure-side leg of the leading-edge horseshoe vortex and along the suction-side corner are influenced most strongly by the high free-stream turbulence. In this study, the end wall surface is classified into seven different regions based on the local heat/mass transfer distribution, and the effects of the high free-stream turbulence on the local heat/mass transfer in each region are discussed in detail.

Endwall Heat (Mass) Transfer in a Turbine Cascade Under Combustor-Level High Free-Stream Turbulence (연소기 출구 난류 상태에서의 터빈 익열 끝벽 열(물질)전달 특성)

  • Jun, Sang-Bae;Lee, Sang-Woo;Park, Byung-Kyu
    • Proceedings of the KSME Conference
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    • 2001.06d
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    • pp.759-764
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    • 2001
  • Heat (mass) transfer characteristics have been investigated on the endwall of a large-scale linear turbine cascade passage under a combustor-level high free-stream turbulence with a large length scale. Local heat (mass) transfer coefficients are measured by using the naphthalene sublimation technique. The result shows that local heat (mass) transfer on the endwall is greatly enhanced in the central region of the turbine passage, but there is no noticeable change in the local heat (mass) transfer in the region suffering severe heat load. Under the high free-stream turbulence, the local heat (mass) transfer coefficient shows more uniform distribution and its average value across the whole endwall region is increased by 26% of that at low turbulence condition. The heat (mass) transfer data on the endwall strongly supports that well-organized vortices near the endwall tends to suffer an suppression by the high free-stream turbulence.

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