• Title/Summary/Keyword: mixed mode

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Mixed mode exciting resonant inverter and control IC applicable to high Performance electronic ballast (고성능 전자식 안정기에 적합한 공진형 인버터의 혼합형 구동방식과 제어 IC)

  • Ryoo, Tae-Ha;Chae, Gyun;Hwang, Jong-Tae;Cho, Gyu-Hyeong
    • Proceedings of the KIEE Conference
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    • 1999.07f
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    • pp.2786-2788
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    • 1999
  • In this paper, a mixed mode exciting resonant inverter topology applicable to high performance electronic ballast is presented. Mixed mode exciting technique combines the attractive features of self exciting resonant inverter with those of external exciting one. The control IC is designed and manufactured by using a 0.8um CMOS process for 5V operation and has only 8 pins. This performs the operations of filament preheating, dimming control, output power regulation and protections. The mixed mode exciting resonant inverter with control IC has very simple structure, high performance and expensive manufacturing cost.

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An elliptical fracture criterion for mixed mode fracture I+II emanating from notches

  • El Minor, H.;Pluvinage, G.;Azari, Z.
    • Structural Engineering and Mechanics
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    • v.26 no.1
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    • pp.87-97
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    • 2007
  • Some mixed mode fracture criterion may be converted in to elliptical or ellipsoidal formula with the aid of mathematical translation. Hence, the crack initiation in mixed mode fracture I+II emanating from notches, has been studied using notched circular ring specimens. On the basis of Irwin (1957) theory, a new criteria in mixed mode fracture I+II, based fracture elliptic criterion and notch stress intensity factors has been developed.

A Study on the mixed mode of Gyro (자이로의 혼합모드 연구)

  • 노영환;방효충;이상용;황규진
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.30-30
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    • 2000
  • In the three axis control of satellite by using reaction wheel and gyro, a Gyro carries out measuring of the attitude angie and the attitude angular velocity. The Gyro is operated by the electronic part and the mechanic actuator. The digital part of the electronic part is consisted of the FPGA (Field Programmable Gate Array), which is one of the methods for designing VLSI (Very Large Scale Integrated Circuit), and the mechanic actuator processes the input/output data by the dynamic model. In the research of the mixed mode of Gyro, the simulation is accomplished by SABER of the mixed mode simulator and the results for the practical implementation of the satellite ACS (Attitude Control System) interfaced with the data processing are proposed.

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Design of 2 Axles Fatigue Test JIG for the Materialization of Mixed Mode (Mode I+II) (혼합모드(Mode I+II)구현을 위한 2축 피로시험 JIG 설계)

  • Choi, Seong-Dae;Cheong, Seon-Hwan;Kim, Gi-Man;Kim, Jam-Kyu;Choi, Myoung-Su;Kim, Woo-Jae
    • Journal of the Korean Society of Industry Convergence
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    • v.11 no.2
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    • pp.59-64
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    • 2008
  • Elements of a mechanical structure are getting from multi-axles stress. so fatigue characteristic experiment Shall execute in multi-axles stress state. it is very hard to apply according to forms of a testing machine and implementation. In this study, 2 axles fatigue testing machine did a design and Development. a new JIG developed to realize a mixed mode. a stress state in mixed mode of a specimen had each other comparison using the Finite element method to examine propriety of a new JIG.

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Crack tip plastic zone under Mode I, Mode II and mixed mode (I+II) conditions

  • Ayatollahi, M.R.;Sedighiani, Karo
    • Structural Engineering and Mechanics
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    • v.36 no.5
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    • pp.575-598
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    • 2010
  • The shape and size of the plastic zone around the crack tip are analyzed under pure mode I, pure mode II and mixed mode (I+II) loading for small scale yielding and for both plane stress and plane strain conditions. A new analytical formulation is presented to determine the radius of the plastic zone in a non-dimensional form. In particular, the effect of T-stress on the plastic zone around the crack tip is studied. The results of this investigation indicate that the stress field with a T-stress always yields a larger plastic zone than the field without a T-stress. It is found that under predominantly mode I loading, the effect of a negative T-stress on the size of the plastic zone is more dramatic than a positive T-stress. However, when mode II portion of loading is dominating the effect of both positive and negative T-stresses on the size of the plastic zone is almost equal. For validating the analytical results, several finite element analyses were performed. It is shown that the results obtained by the proposed analytical formulation are in very good agreements with those obtained from the finite element analyses.

Separation of Nattokinase from Bacillus subtilis Fermentation Broth by Expanded Bed Adsorption with Mixed-mode Adsorbent

  • Lu Miao-Hua;Lin Dong-Qiang;Wu Yuan-Chun;Yun Jun-Xian;Mei Le-He;Yao Shan-Jing
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.2
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    • pp.128-135
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    • 2005
  • Mixed-mode hydrophobic/ionic matrices exhibit a salt-tolerant property for adsorbing target protein from high-ionic strength feedstock, which allows the application of undiluted feedstock via an expanded bed process. In the present work, a new type of mixed-mode adsorbent designed for expanded bed adsorption, Fastline $PRO^{\circledR}$, was challenged for the capture of nattokinase from the high ionic fermentation broth of Bacillus subtilis. Two important factors, pH and ion concentration, were investigated with regard to the performance of nattokinase ad-sorption. Under initial fermentation broth conditions (pH 6.6 and conductivity of 10 mS/cm) the adsorption capacity of nattokinase with Fastline PRO was high, with a maximum capacity of 5,350 U/mL adsorbent. The elution behaviors were investigated using packed bed adsorption experiments, which demonstrated that the effective desorption of nattokinase could be achieved by effecting a pH of 9.5. The biomass pulse response experiments were carried out in order to evaluate the biomass/adsorbent interactions between Bacillus subtilis cells and Fastline PRO, and to demonstrate a stable expanded bed in the feedstock containing Bacillus subtilis cells. Finally, an EBA process, utilizing mixed-mode Fastline PRO adsorbent, was optimized to capture nattokinase directly from the fermentation broth. The purification factor reached 12.3, thereby demonstrating the advantages of the mixed-mode EBA in enzyme separation.

Stress intensity factor in cracked plate reinforced with a plate under mixed mode loading (혼합형 하중항에 있는 판재로 보강된 균열판의 응력세기계수)

  • Lee, Kang-Yong;Kim, Ok-Whan
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.22 no.3
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    • pp.569-578
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    • 1998
  • The mode I and II stress intensity factors have been calculated theoretically for the cracked plate reinforced with a plate by symmetric spot welding under remote mixed mode loading. This is the extension of authors' previous work for the reinforced cracked plate under remote normal stress. Regardless of loading types, the reinforcement effect gets better as one joining spot is closer to the crack tip and the others are closer to the crack surface, and optimum number of the joining spots can be existed. For the present model, the remote loading parallel to crack surface produces the mode I stress intensity factor.

Study on the Characteristics of Propagating Fatiguc Crack under Mixed-Mode Loading Condition (혼합모드하중상태에서 전파하는 피로크랙특성에 관한 연구)

  • 송삼홍;최진호;임진학
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1993.10a
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    • pp.644-649
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    • 1993
  • Practical structures are subject not only to tension but also to shear and torsional loading. In this study, the mode 1 and 2 stress intensity factors of specimens were calculated by using elastic finite element mothod. The stress fields at the crack tip subjected to mixed-mode loading were also studied by usingf eleatic finite element method and were compared with theoretical results. The three-point-bending, four-point-bending, and mixed-mode-loading experiment were carried out. And, crack propagation rate da/dN and crack growth direction were examined. Also, the elastic finite element method was applied to calculate the stress intensity factors of branch crack tip and we relate the stress intenity factor range of branch crack tip(the result of FEM) to crack propagation rate(the experimental result). The .DELTA. -da/dN relation corelated with that of mode 1.

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A Study on Source Mechanisms of Micro-Fracture Related to Rock Failure Through Acoustio Emission Measurement (음향 방사법 (AE)을 이용한 암석파괴와 관련된 미세균열원의 기구에 대한 연구)

  • 김교원
    • Proceedings of the Korean Geotechical Society Conference
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    • 1989.10a
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    • pp.1.2-17
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    • 1989
  • 花崗巖 Beam 試料에 대하여 4-Point Bending 試驗이 진행되는 동안 試料 破壤에 隋伴된 AE 信號를 Calibrated PZT Transducer와 6-Channel Recording System으로 기록하여 分析함으로서 微細 龜裂源의 特性과 機構를 糾明하였다. 微細 龜裂의 體積은 수 um3에서 150.000um3의 넓은 범위를 보였으며, 引張形 龜裂이 斷形에 비하여 大體的으로 큰 것으로 밝혀 졌다. 龜裂源에서의 强度는 Mode I 荷重 下에서 기록된 것이 Mixed Mode 試驗에서 얻어진 것보다 그 平均値가 약 3배 정도 크게 나타났으나, 전체 AE 數에 있어어는 反對로 Mixed Mode 試驗에서 기록된 것의 약 25% 밖에 되지 않아서 같은 크기의 破壤面을 形成하는데 必要한 에너지 要求量이 일정함을 暗示하였다. 미세 龜裂面의 方位는 垂直 및 水平에 近接한 傾斜를 가지며 走向은 최종 試料의 破壤面과 일치할 뿐만 아니라 龜裂源이 시료 破壤面에 집중되게 分布하여서 微細 龜裂이 試料龜裂을 야기시키는 原因임을 알 수 있었다. 또한, Mode I 荷重 下에서는 引張形의 微細龜裂이 압도적으로 優勢하였고, Mixed Mode 荷重 下에서는 引張과 斷形의 微細龜裂이 약 3,6:1 比率로 分布하여서 荷重 條件이 微細 龜裂의 機構와 密接한 關係가 있음을 알 수 있었다.

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