• Title/Summary/Keyword: Fluid-bed

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Direct Open Venous Drainage: An Alternative Choice for Flap Congestion Salvage

  • Park, Su Han;Choi, Woo Young;Son, Kyung Min;Cheon, Ji Seon;Yang, Jeong Yeol
    • Archives of Craniofacial Surgery
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    • v.16 no.3
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    • pp.143-146
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    • 2015
  • In this report, we present a scalp defect reconstruction with lateral arm free flap. We highlight the difficulty in obtaining a recipient vein and the venous drainage managed through an open end of the donor vein. A 52-year-old woman presented with a pressure sore on the left scalp. A lateral arm free flap was transferred to cover this $8{\times}6cm$ defect. The arterial anastomosis was successful, but no recipient vein could be identified within the wound bed. Instead, we used a donor venous end for the direct open venous drainage. In order to keep this exposed venous end patent, we applied heparin-soaked gauze dressing to the wound. Also, the vein end was mechanically dilated and irrigated with heparin solution at two hour intervals. Along with fluid management and blood transfusion, this management was continued for the five days after the operation. The flap survived well without any complication. Through this case, we were able to demonstrate that venous congestion can be avoided by drainage of the venous blood through an open vessel without the use of leeches.

Discussion on the Practical Use of CFD for Grate Type Waste Incinerators (회격자식 소각로의 열유동 해석과 결과 분석에 대한 고찰)

  • Ryu C.;Choi S.
    • Journal of computational fluids engineering
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    • v.7 no.3
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    • pp.17-26
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    • 2002
  • Computational fluid dynamic(CFD) analysis has been frequently applied to the waste incinerators to understand the flow performance for various design and operating parameters. Since the computational modeling inevitably requires many simplifications and complicated sub-models, validity of the results should be carefully evaluated. In this study, major computational modeling and procedure of usual simulation methods for the grate-type waste incinerators were assessed. Usual simulation method does not explicitly incorporate the waste combustion, simply by assuming the combustion gas properties from the waste bed which is treated as an inlet plane. However, effect of this arbitrary assumption on the overall flow pattern is not significant, since the flow pattern is dominated by strong pattern of jet flows of the secondary air. Thus, this method is valid in understanding the effect of flow-related parameters. In analyzing the results, deriving conclusive information directly from temperature and chemical species concentration should be avoided, since the model prediction for the gaseous reaction and the radiation reveals significant discrepancies against the actual phenomena. Use of quantitative measures such as residence time is very efficient in evaluating the flow performance.

A Study on Velocity Profiles between Two Baffles in a Horizontal Circular Tube

  • Chang, Tae-Hyun;Lee, Chang-Hoan
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.2
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    • pp.136-142
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    • 2015
  • The shell and tube heat exchanger is an essential part of a power plant for recovering transfer heat between the feed water of a boiler and the wasted heat. The baffles are also an important element inside the heat exchanger. Internal materials influence the flow pattern in the bed. The influence of baffles in the velocity profiles was observed using a three-dimensional PIV (Particle Image Velocimetry) around baffles in a horizontal circular tube. The velocity of the particles was measured before the baffle and between them in the test tube. Results show that the velocity vectors near the front baffle flow along the vertical wall, and then concentrate on the upper opening of the front baffle. The velocity profiles circulate in the front and rear baffle. These profiles are related to the Reynolds number (Re) or the flow intensity. Velocity profiles at lower Re number showed complicated mixing to obtain the velocities and concentrate on the lower opening of the rear baffle as front wall. Numerical simulations were performed to investigate the effects of the baffle and obtain the velocity profiles between the two baffles. In this study, a commercial CFD package, Fluent 6.3.21 with the turbulent flow modeling, k-${\epsilon}$ are adopted. The path line and local axial velocities are calculated between two baffles using this program.

Herpes Zoster Meningitis Confirmed by Detection of Varicella-Zoster Virus DNA Using the Polymerase Chain Reaction -A case report- (중합효소 연쇄반응을 이용한 Varicella-Zoster Virus DNA 검출로 확인된 대상포진 수막염 -증례 보고-)

  • Heo, Hu Man;Choi, Yu Sun;Park, Seong Kyu
    • The Korean Journal of Pain
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    • v.18 no.2
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    • pp.210-213
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    • 2005
  • Acute viral meningitis and myositis are rare complications of varicella-zoster virus (VZV) reactivation. A 71-years-old immunocompetent man, who presented with lower back pain radiating to the left lower extremities, developed vesicles on the L5 dermatomal area. The next day, he had complained of aberrant vesicles on the trunk, face and scalp, with generalized myalgia, headache and dizziness. He was confirmed with VZV meningitis and myositis, as demonstrated by the presence of VZV DNA in the blood and cerebral spinal fluid using a polymerase chain reaction (PCR) amplification. PCR has been used in patients with a VZV infection associated neurological symptoms, and provides a useful tool for the early diagnosis of VZV-associated neurological disease. The patient was treated with bed rest, with intravenous acyclovir for the VZV infection, and intravenous Patient-controlled Analgesia for pain management and the prevention of postherpetic neuralgia. When he visited the outpatient department 3 months later, the skin lesion, leg pain, headache and myalgia had all improved, without sequelae. Here, this case is reported, with a discussion of the relevant literature on its diagnosis and management.

On the Sediment Transport Characteristics of the Bottom Turbulent Boundary Layer (저면난류경계층(底面亂流境界層)의 저질이동특성(底質移動特性))

  • Kim, Nam Hyeong;Kiyoshi, Takikawa
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.13 no.2
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    • pp.267-277
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    • 1993
  • A finite element method(FEM) is presented and applied to the two-dimensional bottom turbulent boundary layer. The time-dependent incompressible motion of a viscous fluid is formulated by using the well-known Navier-Stokes equations and vorticity equation in terms of the velocity and pressure fields. The general numerical formulation is based on Galerkin method and solved by introducing the mixing length theory of Prandtl for eddy kinematic viscosity of a turbulent flow field. Numerical computations of the transport of sediment on an arbitrary sea-bed due to wave motion in the turbulent boundary layer are carried out. The results obtained by the FEM made clear the difference in characteristic features between the boundary layer due to oscillatory flow and the boundary layer due to wave motion.

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A Decomposition Based MDO by Coordination of Disciplinary Subspace Optimization (분야별 하부시스템의 최적화를 통합한 분해기반 MDO 방법론)

  • Jeong, Hui-Seok;Lee, Jong-Su
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.9
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    • pp.1822-1830
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    • 2002
  • The paper describes the development of a decomposition based multidisciplinary design optimization (MDO) method that coordinates each of disciplinary subspace optimization (DSO). A multidisciplinary design system considered in the present study is decomposed into a number of subspaces based on their own design objective and constraints associated with engineering discipline. The coupled relations among subspaces are identified by interdisciplinary design variables. Each of subsystem level optimization, that is DSO would be performed in parallel, and the system level coordination is determined by the first order optimal sensitivities of subspace objective functions with respect to interdisciplinary design variables. The central of the present work resides on the formulation of system level coordination strategy and its capability in decomposition based MDO. A fluid-structure coupled design problem is explored as a test-bed to support the proposed MDO method.

A numerical study on design parameters of pyrolysis-melting incinerator (열분해 용융 소각로 설계인자 도출을 위한 수치해석적 연구)

  • Shin, Dong-Hoon;Jeon, Byung-Il;Lee, Jin-Ho;Hwang, Jung-Ho;Ryu, Tae-Oo;Park, Dae-Gyu
    • 한국연소학회:학술대회논문집
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    • 2003.12a
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    • pp.243-250
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    • 2003
  • The present study discuss about numerical methods to analyze design parameters of pyrolysis-melting incineration system. Various numerical methods of different viewpoint are introduced to simulate the performance of the system. Process analysis of the overall system is the beginning procedure of basic design process. Heat and material flow of each element are connected and are influential to each other, hence, an appropriate process modeling should be executed to prevent from unacceptable process design concepts that may results in system failure. Models to simulate performance of each elementary facility generate valuable informations on design and operation parameters, and, derive the basic design concept to be optimized. A pyrolysis model derived from waste bed combustion model is introduced to simulate the mass conversion and heat transfer in the pyrolysis process. CFD(Computational fluid dynamics) is an effective method to optimize the thermal reacting flow in various reactors such as combustor and heat exchanger. Secondary air jets arrangement and the shape of the combustor could be optimized by CFD technology.

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Two Cases of Spontaneous Intracranial Hypotension Treated with Epidural Blood Patch (자발성 두개내 저압환자의 경막외 혈액봉합술 치험 2예)

  • Cho, Soung-Kyung;Joo, Hyun-Chul;Park, Chan-Hong;Kim, Bong-Il;Lee, Sang-Hwa;Oh, Hee-Jong
    • The Korean Journal of Pain
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    • v.12 no.1
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    • pp.152-156
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    • 1999
  • Spontaneous intracranial hypotension (SIH) is a rare syndrome which causes postural headache associated with low cerebrospinal fluid (CSF) pressure, without preceding events such as lumbar puncture, back trauma, operative procedure or illness. The headche is usually accompanied by nausea, vomiting, tinnitus, neck stiffness, vertigo, photophobia and in rare cases diplopia, transient visual obscuration. Brain MRI may show subdural effusion, downward displacement of brain and diffuse and continuous meningeal enhancement when enhanced by gadolinium. Low opening pressure was shown through lumbar puncture. The value of protein and cell count of CSF may be slightly elevated. This syndrome usually resolves itself spontaneously or with strict bed rest. When the headache is persistent or incapacitating, more aggressive treatment may be necessary. We treated two cases of SIH in which epidural blood patch produced immediate and complete relief of the symptoms.

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Use of HCI Program for Optimization of Operating Conditions in Analytical and Preparative Chromatography (분석 및 분리용 크로마토그래피에서 조업조건의 최적화를 위한 HCI 프로그램의 이용)

  • Lee, Ju-Won;Lee, Min-U;No, Gyeong-Ho
    • KSBB Journal
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    • v.14 no.4
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    • pp.408-413
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    • 1999
  • To separate mixtures analytically and preparatively by LC (Liquid Chormatography), the operating conditions of analytical chromatography should be determined. The HCI program was utilized to find the optimum operating condition accurately and rapidly, and to reduce the number of experiments. In an analytical chromatography, based on the resolution and analysis time, the experimental conditons of deoxyribonucleosides and phopholipids were fixed in terms of taxol was calculated, and the collection time was predicted for the mixture of 5'-IMP and 5'-GMP from the elution profile when and purity wer known.

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Analysis of Services and Cost in CVA Patients by Severity in Hospital-based Home Health Care (병원중심 가정간호 뇌혈관질환자의 중증도별 서비스 특성 및 비용 분석)

  • 장인순;황나미
    • Journal of Korean Academy of Nursing
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    • v.31 no.4
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    • pp.619-630
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    • 2001
  • Purpose: The purpose of this study was to analyze the differences in terms of services and cost between CVA without typical diseases (Group I), and CVA with typical diseases (Group II), in their Hospital-based home health care. Method: The subjects of this study were 308 CVA patients who used home care nursing during the second phase demonstration project of their hospital-based home health care. Results: The results of the study was as follows 1. Group II had more home visit (15.3/12.7) (p>0.05), and cases of death when home care (16.8/11.4) (p<0.05). 2. Group II needed more services than Group I such as bladder irrigation, skin care, bed sore care, glycerin enema, finger enema, lung care, urine sugar test, monitoring and surveillance of fluid infusion and R.O.M exercise (p<0.05). 3. The variables that showed statistical significance in the regression analysis were family style, OPD visit, level of consciousness, patient's state on termination of home care, and some extend of home health care services (R2=0.373, 0.205). Conclusion: Home nursing care needs to be planned by severity in Hospital-based home health care for CVA patients.

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