• Title/Summary/Keyword: Butterfly

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Microscopic versus Endoscopic Inlay Butterfly Cartilage Tympanoplasty

  • Lee, Se A;Kang, Hyun Tag;Lee, Yun Ji;Kim, Bo Gyung;Lee, Jong Dae
    • Korean Journal of Audiology
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    • v.23 no.3
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    • pp.140-144
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    • 2019
  • Background and Objectives: Inlay butterfly cartilage tympanoplasty makes the graft easy, and reduces operating time. The present study aimed to investigate the outcomes of microscopic versus endoscopic inlay butterfly cartilage tympanoplasty. Subjects and Methods: In this retrospective study, the outcomes of 63 patients who underwent inlay butterfly cartilage tympanoplasty with small to medium chronic tympanic membrane perforation were evaluated. Twenty-four patients underwent conventional microscopic tympanoplasty and 39 underwent endoscopic tympanoplasty. The outcomes were analyzed in terms of the hearing gain and graft success rate. Results: The surgical success rate was 95.8% in the patients who underwent conventional microscopic tympanoplasty and 92.3% in those who underwent endoscopic tympanoplasty. In both groups of patients, the postoperative air-bone gap (ABG) was significantly lower than the preoperative ABG. There were no significant differences between the preoperative and postoperative ABG values in either group. Conclusions: Endoscopic inlay tympanoplasty using the butterfly cartilage technique appears to be an effective alternative to microscopic tympanoplasty and results in excellent hearing.

Integrative Korean Medicine Treatment for Low Back Pain with Butterfly Vertebra: Two Clinical Cases

  • Dong-Hwan Lee;Oh-Bin Kwon;Jae-Young Lee;Hyo-Rim Kim;Tae-Jun Lee;Sung-Hwan Cho;Kang-Moo Goo;Ja-Yean Son;Seok-Gyu Yang;Yu-Ra Im
    • Journal of Acupuncture Research
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    • v.41
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    • pp.168-175
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    • 2024
  • The butterfly vertebra is a rare congenital anomaly of the spine, which arises from an asymmetric fusion defect in the embryonic vertebral column. This report delineates an integrative Korean medicine treatment administered to two patients who presented with low back pain associated with asymptomatic butterfly vertebrae. The patients received comprehensive treatment comprising acupuncture, Chuna therapy, pharmacopuncture, herbal medicine, and cupping therapy. The efficacy of the treatments was assessed utilizing diverse parameters, including a numerical rating scale, range of motion of the lumbar spine, Oswestry Disability Index, EuroQoL 5-Dimension 5-Level, and patient global impression of change. After the treatment, a notable improvement was noted in the evaluated indicators. These positive outcomes suggest that integrative Korean medicine treatment is suitable for patients experiencing low back pain associated with asymptomatic butterfly vertebrae.

Design of a Robust Controller for the Butterfly Valve with Considering the Friction (마찰을 고려한 버터플라이 밸브의 강인 제어기 설계)

  • Choi, Jeongju
    • Journal of the Korean Society for Precision Engineering
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    • v.30 no.8
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    • pp.824-830
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    • 2013
  • We propose a tracking control system for butterfly valves. A sliding mode controller with a fuzzy-neural network algorithm was applied to the design of the tracking control system. The control scheme used the real-time update law for the unmodeled system dynamics using a fuzzy-neural network algorithm. The performance of the proposed control system was assessed through a range of experiments.

Butterfly Log-MAP Decoding Algorithm

  • Hou, Jia;Lee, Moon Ho;Kim, Chang Joo
    • Journal of Communications and Networks
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    • v.6 no.3
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    • pp.209-215
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    • 2004
  • In this paper, a butterfly Log-MAP decoding algorithm for turbo code is proposed. Different from the conventional turbo decoder, we derived a generalized formula to calculate the log-likelihood ratio (LLR) and drew a modified butterfly states diagram in 8-states systematic turbo coded system. By comparing the complexity of conventional implementations, the proposed algorithm can efficiently reduce both the computations and work units without bit error ratio (BER) performance degradation.

RADIX-2 BUTTERFLY 연산회로의 설계

  • 최병윤;신경욱;유종근;임충빈;김봉열;이문기
    • Proceedings of the Korean Institute of Communication Sciences Conference
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    • 1986.04a
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    • pp.177-180
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    • 1986
  • A high performance Butterfly Arithmetic Unit for FFT processor using two adders is proposed in this papers, which is Based on the distributed and merged arithmetic. Due to simple and easy architecture to implement, this proposed processor is well suited to systolic FFT processor. Simulation was performance using YSLOG (Yonsei logic simulator) on IBM AT computer, to verify logic. By using 3um double Metal CMOS technology,Butterfly arithmetic have been achieved in 1.2 usec.

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Downstream flow characteristics of butterfly valves (대용량 버터플라이 밸브 후단 유동 특성)

  • Choi, Seok-Ho;Paek, Min-Su;Moon, Kil-Ho
    • 유체기계공업학회:학술대회논문집
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    • 2003.12a
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    • pp.573-576
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    • 2003
  • In butterfly control valve, a multi-hole orifice is attached downstream of valve to stabilize flow fluctuation. The computational simulation is conducted to analyze valve flow characteristics. The results show that the velocity distribution of downstream of valve with the orifice is improved compared to non-orifice case. Test result in site is 60% reduction in vibration.

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CHARACTERISTIC OF BUTTERFLY VALVE FLOW WITH DIFFERENT DESIGN FACTORS (설계인자 변경에 따른 버터플라이 밸브 유동 특성에 관한 연구)

  • Lee, J.W.;Choi, H.K.;Yoo, G.J.
    • 한국전산유체공학회:학술대회논문집
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    • 2009.11a
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    • pp.170-176
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    • 2009
  • Flow control butterfly valve(FCBV) is known to have difficulty in controlling flow rate along valve opening due to its high flow rate. In low opening condition, the butterfly valve also has some shortcomings such as noise, vibration and erosion which are mostly caused by cavitation effects. Therefore, the FCBV requires proper remedies to reduce cavitation effects and to improve flow control performance. Numerical analysis is applied to FCBV flow to find effects of design factors such as seat diameter and valve opening rate. Cases with 3 different sizes of seat diameter and various valve opening rate are selected for the numerical analysis. From the analysis results, it is found that the FCBV with small seat diameter shows better pressure loss performance and reduced cavitation effects.

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CHARACTERISTIC OF BUTTERFLY VALVE FLOW WITH DIFFERENT DESIGN FACTORS (설계인자 변경에 따른 버터플라이 밸브 유동 특성에 관한 연구)

  • Lee, J.W.;Choi, H.K.;Yoo, G.J.
    • Journal of computational fluids engineering
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    • v.15 no.1
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    • pp.64-70
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    • 2010
  • Flow control butterfly valve(FCBV) is known to have difficulty in controlling flow rate along valve opening due to its high flow rate. In low opening condition, the butterfly valve also has some shortcomings such as noise, vibration and erosion which are mostly caused by cavitation effects. Therefore, the FCBV requires proper remedies to reduce cavitation effects and to improve flow control performance. Numerical analysis is applied to FCBV flow to find effects of design factors such as seat diameter and valve opening rate. Cases with 3 different sizes of seat diameter and various valve opening rate are selected for the numerical analysis. From the analysis results, it is found that the FCBV with small seat diameter shows better pressure loss performance and reduced cavitation effects.

Numerical and Experimental Study on the Wake Flow of a Butterfly-Type Valve (원관내 버터플라이 밸브 후류에 대한 수치해석 및 실험적 연구)

  • Shim, Jo-Seph;Huh, Hyeung-Suk;Suh, Young-Kweon
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2002.05a
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    • pp.220-224
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    • 2002
  • In this paper, flow in the wake region of a butterfly valve is studied numerically and experimentally. The disk angle of the valve is fixed as $30^{\circ}$ and the free stream velocity as 0.13m/s in the experiment. Numerical analysis is performed in similitude of the experiment. The standard LES model is used to represent the turbulence effect in the commercial code Fluent 5.5. It is shown that the numerical result is similar to the experimental result for the wake flow of a butterfly-type valve.

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CHAOS IN PRODUCTION PLANNING

  • Haghighirad, Farzad;Makui, Ahmad;Ashtiani, Behzad
    • Journal of applied mathematics & informatics
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    • v.26 no.3_4
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    • pp.739-750
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    • 2008
  • A phenomenon which is seen in some of the manufacturing systems and production planning is chaos and the butterfly effect. The butterfly effect points out that in case of the presence of nonlinear relations in system and incorrect estimation of initial values of variables, the error in the estimates of system state will be intensified, and after a while there will be a large distance between available state of system and reality. Using mathematical means and computer simulation, we have tried to demonstrate that in a production system the numerical combination of Cycle Time (CT), Adjustment Time between existing and desired Work In Progress (WIP), and Adjustment Time between current and desired inventory can lead to chaos and butterfly effect in the behavior of the inventory state variable. Our paper concludes with a discussion of a hypothesis that emerged from this research.

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