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Reconstructive Trends in Post-Ablation Patients with Esophagus and Hypopharynx Defect

  • Ki, Sae Hwi;Choi, Jong Hwan;Sim, Seung Hyun
    • Archives of Craniofacial Surgery
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    • v.16 no.3
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    • pp.105-113
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    • 2015
  • The main challenge in pharyngoesophageal reconstruction is the restoration of swallow and speech functions. The aim of this paper is to review the reconstructive options and associated complications for patients with head and neck cancer. A literature review was performed for pharynoesophagus reconstruction after ablative surgery of head and neck cancer for studies published between January 1980 to July 2015 and listed in the PubMed database. Search queries were made using a combination of 'esophagus' and 'free flap', 'microsurgical', or 'free tissue transfer'. The search query resulted in 123 studies, of which 33 studies were full text publications that met inclusion criteria. Further review into the reference of these 33 studies resulted in 15 additional studies to be included. The pharyngoesophagus reconstruction should be individualized for each patient and clinical context. Fasciocutaneous free flap and pedicled flap are effective for partial phayngoesophageal defect. Fasciocutaneous free flap and jejunal free flap are effective for circumferential defect. Pedicled flaps remain a safe option in the context of high surgical risk patients, presence of fistula. Among free flaps, anterolateral thigh free flap and jejunal free flap were associated with superior outcomes, when compared with radial forearm free flap. Speech function is reported to be better for the fasciocutaneous free flap than for the jejunal free flap.

Collision-Free Motion Planning of a Robot Using Free Arc concept (프리아크 개념을 이용한 로봇의 충돌회피 동작 계획)

  • Lee, Seok-Won;Nam, Yun-Seok;Lee, Beom-Hee
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.3
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    • pp.317-328
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    • 2000
  • This paper presents an effective approach to collision-free motion planning of a robot in the work-space including time-varying obstacles. The free arc is defined as a set composed of the configuration points of the robot satisfying collision-free motion constraint at each sampling time. We represent this free arc with respect to the new coordinate frame centered at the goal configuration and there for the collision-free path satisfying motion constraint is obtained by connecting the configuration points of the free arc at each sampling mined from the sequence of free arcs the optimality is determined by the performance index. Therefore the complicated collision-free motion planning problem of a robot is transformed to a simplified SUB_Optimal Collision Avoidance Problem(SOCAP). We analyze the completeness of the proposed approach and show that it is partly guaranteed using the backward motion. Computational complexity of our approach is analyzed theoretically and practical computation time is compared with that of the other method. Simulation results for two cally and practical computation time is compared with that of the other method. Simulation results for two SCARA robot manipulators are presented to verify the efficacy of the proposed method.

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Numerical Analysis of Free-Surface Flows Using Improved Adaptable Surface Particle Method Based on Grid System (개선된 격자기반 적합 표면입자법을 이용한 자유표면유동 수치해석)

  • Shin, Young-Seop
    • Journal of the Society of Naval Architects of Korea
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    • v.58 no.2
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    • pp.90-96
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    • 2021
  • In this study, the method of determining the state of grid points in the adaptable surface particle method based on grid system developed as a free-surface tracing method was improved. The adaptable surface particle method is a method of determining the state of the grid point according to the shape of the free-surface and obtaining the intersection of the given free-surface and grid line where the state of the grid point changes. It is difficult to determine the state of grid points in the event of rapid flow, such as collision or separation of free-surfaces, and this study suggests a method for determining the state of current grid points using the state of surrounding grid points where the state of grid point are known. A grid layer value was assigned sequentially to a grid away from the free-surface, centering on the boundary cell where the free-surface exists, to identify the connection information that the grid was separated from the free-surface, and to determine the state of the grid point sequentially from a grid away from the free-surface to a grid close to the free-surface. To verify the improved method, a numerical analysis was made on the problem of dam break in which a sudden collision of free-surface occurred and the results were compared, and the results were relatively reasonable.

Automatic Panelizing Algorithms of Free-form Buildings

  • Lee, Donghoon;Lim, Jeeyoung;Habimana, Gilbert;Lee, Taick-Oun;Kim, Sunkuk
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.425-428
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    • 2015
  • New technologies using a CNC machine are being developed to reduce the production cost of free-form buildings. For production of free-form members using such technologies, vast free-form buildings should be first split into multiple panels that are productible. Taking into consideration of the curved surface of free-form members, the segmented free-form panels may vary in shape and size, which may cause a lot of errors. In addition, it is time-consuming for the work. However, the current panelizing work is completed with the trials and errors of engineers and architectural designers even in large-scale projects, which results in increased construction duration and cost. Thus, it is necessary to develop a technology for panelizing free-form panels so as to maximize the economic feasibility of production technologies for free-form concrete members. The study intends to develeop automatic panelizing algorithms of free-form buildings considering the curved surface and size of free-form panels and the production conditions. The developed algorithms will be useful in applying the production technologies of free-form buildings using CNC machine and reducing the cost.

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ON FREE AND TORSION-FREE AUTOMATA

  • Park, Chin-Hong
    • Journal of applied mathematics & informatics
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    • v.1 no.1
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    • pp.75-78
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    • 1994
  • In this paper we define free torsion-free and torsion-free completely on an automaton. We prove some properties of them which are important

Recent Progress in Pb-free Solders and Soldering Technology: Fundamentals, Reliability Issues and Applications

  • Kang Sung Kwon
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2004.09a
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    • pp.1-26
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    • 2004
  • The implementation of Pb-free solder technology is making good progress in electronic industry. Further understanding on fundamental issues on Pb-free solders/processes is required to reduce reliability risk factors of Pb-free solder joints. Several reliability issues including thermal fatigue, impact reliability, IMC growth, spalling, void formation are reviewed for Pb-free solder joints. Several applications of Pb-free technology are discussed, such as Pb-free, CBGA, CuCGA, flip chips, and wafer bumping by IMS.

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Free-range Poultry Production - A Review

  • Miao, Z.H.;Glatz, P.C.;Ru, Y.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.1
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    • pp.113-132
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    • 2005
  • With the demand for free-range products increasing and the pressure on the intensive poultry industry to improve poultry welfare especially in western countries, the number of free-range poultry farms has increased significantly. The USA, Australia and European countries have developed Codes of Practice for free-range poultry farming which detail the minimum standards of husbandry and welfare for birds. However, the performance and liveability of free-range birds needs to be improved and more knowledge is required on bird husbandry, feed supply, disease control and heat wave management. This review examines the husbandry, welfare, nutrition and disease issues associated with free-range poultry systems and discusses the potential of incorporating free-range poultry into a crop-pasture rotation system.

The Metabolites of a Marine Mollusk Mytilus edulis:- Isolation of Taurine and Compositions of Free Fatty Acids and Free Amino acids-

  • Cho, Yong-Jin;Son, Byeng-Wha;Choi, Hong-Dae
    • Natural Product Sciences
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    • v.1 no.1
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    • pp.5-9
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    • 1995
  • The metabolites of marine mollusk Mytilus edulis were isolated and characterized, revealing the presence of the rare free fatty acids and proteinogenic amino acids together with a non-proteinogenic free amino acid, taurine. The free fatty acids in this organism were particularly interesting for the presence of both unusual n-6 acid [20:4 (n-6)] and triple bond containing acid (2,5-octadecadiynoic acid). In addition to the proteinogenic amino acids commonly found in proteins, non-proteinogenic free amino acid taurine was isolated and the structure was determined by its physicochemical properties. Recently taurine has been given much interest in the molecular level because of diverse biological activities and the medicinal properties. Furthermore, the result of the analyses of analyses of free amino acids showed that glycine, glutamic acid, serine and alanine, which were considered to be related to the taste of this organism, are predominantly present.

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Power System Stabilizer using the Free Model

  • Kim, Ho-Chan;Oh, Seong-Bo;Lee, Kwang-Yeon
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.139.3-139
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    • 2001
  • The free-model concept is introduced as an alternative intelligent system technique to design a controller with input and output data only. The idea of free model comes from the Taylor series approximation, where an output can be estimated when such data as position, velocity, and acceleration are known. The parameters in the free model can be estimated using the input-output data and a controller can be designed based on the free model. The free model thus developed is shown to be controllable, observable, and robust. The accuracy of the free-model approximation can be improved by increasing the observation window and the order of the free model. The LQR method is applied to the free model to design power system stabilizers ...

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Study on the two-dimensional Formation Control of Free Surface of Magnetic Fluid by Electromagnetic Force (전자기력에 의한 자성유체의 2차원 자유표면 형상 제어에 관한 연구)

  • 안창호;지병걸;이은준;박명관
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.979-982
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    • 2003
  • In this study, because of change in electromagnetic force, deformation of the free surface motion of a magnetic fluid is changed. Deformation of the free surface motion of a magnetic fluid for the change in electromagnetic force is discussed and carried out theoretically and experimentally on the basis of Rosensweig Ferrohydrodynamic Bernoulli Equation. Objective of this study explicates free surface motion by electromagnetic force and planes to designed controller. To control free surface of magnetic fluid, it embody designed two-dimensional free surface form of magnetic fluid. By using this characteristics, they applied to oscillator for surface control, flow control, boundary layer control. Strength of magnetic field and height of free surface of magnetic fluid measure as a hall-effect sensor. As performing height control of magnetic fluid, the result will be presented possibility of free surface deformation control.

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