• 제목/요약/키워드: FIV

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Successful Management of Immune-Mediated Hemolytic Anemia Secondary to Infection with Cytauxzoon felis and Feline Immunodeficiency Virus

  • Choi, Hyeong-Il;Kim, Joonyong;Han, Jae-Ik;Kim, Ha-Jung
    • 한국임상수의학회지
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    • 제37권4호
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    • pp.223-226
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    • 2020
  • Cytauxzoonosis is caused by Cytauxzoon felis (C. felis) in wild and domestic cats. However, cytauxzoonosis is uncommon in Asia. Additionally, clinical reports of C. felis infection along with associated complications are rare. A seven-year-old neutered male Maine Coon cat was presented with acute dyspnea and lethargy despite the absence of a history of overseas travel. Mild regenerative anemia and autoagglutination were detected in hematological investigations. The parasitic and viral PCR assays revealed infection with C. felis and feline immunodeficiency virus (FIV). Thoracic radiographs showed pleural effusion with secondary bacterial infection. Ultimately, a diagnosis of infection-induced secondary immune-mediated hemolytic anemia (IMHA) and pyothorax was established. The cat was treated with a combination of atovaquone, prednisolone, and cyclosporine over 6 months and the final treatment was completed 8 months after initiation of therapy. This is the first report of its kind demonstrating successful management of feline IMHA and fatal pyothorax induced by FIV and C. felis in South Korea.

한국표준원전 증기발생기의 관막음 집중 영역 근방에서의 유체유발진동 특성해석 (Characteristics of Flow-induced Vibration for KSNP Steam Generator Tube at Concentrated Tube Plugging Zone)

  • 유기완;조봉호;박치용;박수기
    • 한국소음진동공학회논문집
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    • 제13권6호
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    • pp.452-459
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    • 2003
  • The characteristics of fluid-elastic instability and effects of turbulent excitations for the KSNP steam generator tubes were investigated numerically. The information for the thermal-hydraulic data of the steam generator has been obtained by using the ATHOS3-MOD1 code and the flow-induced vibration(FIV) analysis has been conducted by using the PIAT(program for Integrity assessment of SG tube) code. The KSNP steam generator has the concentrated plugging zone at the vicinity of the stay cylinder inside the SG. To investigate the cause of the concentrated tube plugging zone, the FIV analysis has been performed for various column and row number of the steam generator tubes. From the results of FIV analysis the stability ratio due to the fluid-elastic instability and vibrational amplitude due to the turbulent excitation in the concentrated plugged zone have a trend of larger values than those of the outer concentrated tube Plugging zone.

Two-way fluid-structure interaction simulation for steady-state vibration of a slender rod using URANS and LES turbulence models

  • Nazari, Tooraj;Rabiee, Ataollah;Kazeminejad, Hossein
    • Nuclear Engineering and Technology
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    • 제51권2호
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    • pp.573-578
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    • 2019
  • Anisotropic distribution of the turbulent kinetic energy and the near-field excitations are the main causes of the steady state Flow-Induced Vibration (FIV) which could lead to fretting wear damage in vertically arranged supported slender rods. In this article, a combined Computational Fluid Dynamics (CFD) and Computational Structural Mechanic (CSM) approach named two-way Fluid-Structure Interaction (FSI) is used to investigate the modal characteristics of a typical rod's vibration. Performance of an Unsteady Reynolds-Average Navier-Stokes (URANS) and Large Eddy Simulation (LES) turbulence models on asymmetric fluctuations of the flow field are investigated. Using the LES turbulence model, any large deformation damps into a weak oscillation which remains in the system. However, it is challenging to use LES in two-way FSI problems from fluid domain discretization point of view which is investigated in this article as the innovation. It is concluded that the near-wall meshes whiten the viscous sub-layer is of great importance to estimate the Root Mean Square (RMS) of FIV amplitude correctly as a significant fretting wear parameter otherwise it merely computes the frequency of FIV.

FIV 시험루프의 유동기인 진동 신호분석 (Flow-Induced Vibration Signal Analysis of the FIV Test Loop)

  • 이강희;강흥석;윤경호;송기남
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.601-606
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    • 2004
  • Vibration spectrums of the test loop according to flow conditions were analyzed in order to identify the sources of vibration at peak frequencies. While a flow condition of the sweep test was changed by varying pump rotational speed from 450 rpm to 1500 rpm by the step 150 rpm, midspan acceleration of the test section in width-direction and dynamic pressure perturbation in the test section were measured. Other sources of vibration due to the flow structure interactions, such as acoustic resonance, blade pulsing frequency and bellows wrinkles, were investigated. Pressure perturbation in the section and acoustic resonance due to branch pipe give major effects to the vibration of the test section in high frequency range of 1.5 kHz to 2.8 kHz.

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고층건물의 풍하중 유발 진동해석 (Wind Load Induced Vibration Analysis for Tall Structure)

  • 김동현;김유성;김요한;김동만;이종욱
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 춘계학술대회 논문집
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    • pp.658-659
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    • 2009
  • In this study, fluid-induced vibration (FIV) analyses have been conducted for tall building structure. In order to investigate the aeroelastic responses of tall building due to wind load, advanced computational analysis system based n computational fluid dynamics(CFD) and computational structural dynamics (CSD) has been developed. Fluid domains are modeled using the computational grid system with local grid deforming technique. A fully implicit time marching scheme based on the Newmark direct integration method is used for computing the coupled aeroelastic governing equations of tall structure for fluid-structure interaction (FSI) problems. Detailed aeroelastic responses and results are presented to show the physical phenomenon of the tall building.

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원통 내부의 전열관 배열에 따른 유체부가질량특성 수치해석 (Numerical Analysis of Hydrodynamic mass for various Tube Arrays in a circular cylindrical shell)

  • 양금희;유기완;박치용
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2011년도 춘계학술대회 논문집
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    • pp.693-699
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    • 2011
  • The outermost SG tubes have more structural problems than inside tubes. Many studies have used a uniform added mass coefficient for all of the SG tubes during the FIV analysis. The purpose of this study is to find out the added mass coefficients for each tube in a cylindrical shell. When a number of tubes are increased, added mass coefficients are also increased. And added mass coefficients at outermost tubes are less than those of inside tubes. According to gap changes between outermost tube and cylindrical shell, added mass coefficients are decreased with increasing the gap. When the gap has very large value, it shows that the added mass coefficient is asymptotically converged to the value of the tube array in a free fluid field.

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Nonlinear Characteristics of Low-speed Flow Induced Vibration for the Safety Design of Micro Air Vehicle

  • 장태진;김동현;이인
    • 한국소음진동공학회논문집
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    • 제12권11호
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    • pp.873-881
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    • 2002
  • The fluid induced vibration (FIV) phenomena of an equivalent airfoil system of MAV have been investigated in low Reynolds number flow region. Unsteady flows with viscosity are computed using two-dimensional incompressible Navier-Stokes equations. The present fluid/structure interaction analysis is based on one of the most accurate computational approach with computational fluid dynamics (CFD) and computational structural dynamics (CSD) techniques. The highly nonlinear fluid/structure interaction phenomena due to severe flow separations have been analyzed for the low Reynolds region that has a dominancy of flow viscosity. The effects of Reynolds number and initial angle of attack on the fluid/structure coupled vibration instability are shown and the qualitative trend of FIV phenomenon is investigated.

Status of selected feline infectious diseases in Gwangju, Korea

  • Juyeon Choi;Kyu-Sung Ahn;Ah-Jin Ahn;SungShik Shin
    • 대한수의학회지
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    • 제63권4호
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    • pp.31.1-31.4
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    • 2023
  • From 2008 to 2017, blood samples from 280 and fecal samples from 149 stray cats in Gwangju, South Korea, were examined for feline immunodeficiency virus (FIV), feline leukemia virus (FeLV), Dirofilaria immitis, and Giardia infections using commercial diagnostic tests. Overall, the combined prevalence of FeLV, FIV, D. immitis, and Giardia was 8.6%, 1.4%, 0.4%, and 2.0%, respectively. FeLV exhibited the highest prevalence rate among the 4 pathogens surveyed, both in the 2008-2009 (9.6%) and 2015-2017 (6.3%) surveys. The results of the feline Giardia study represent the first prevalence report of Giardia infection among stray cats in Korea.