• 제목/요약/키워드: Multiple injection

검색결과 408건 처리시간 0.031초

Study of Magnetic Helicity Injection in the Active Region NOAA 9236 Producing Multiple CME Events

  • Park, Sung-Hong;Cho, Kyung-Suk;Bong, Su-Chan;Park, Young-Deuk
    • 천문학회보
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    • 제36권2호
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    • pp.84.1-84.1
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    • 2011
  • In this study, we intend to inquire of how the temporal variation and spatial distribution of magnetic helicity injection in a CME-producing solar active region are related to the CME occurrence. We therefore investigate long-term (a few days) variation of magnetic helicity injection in the active region NOAA 9236 which produced multiple CME events. As a result, it is found that a noticeable increase in helicity of negative sign was first made for the first ~1.5 days and then 6 CMEs occurred while the relatively more injection of oppositely signed (positive) helicity was taking place for the next ~2 days. Afterwards, 2 CMEs in the region occurred while a more negative helicity is being injected again compared to a positive helicity. In addition, from helicity flux density maps, we found that the CMEs originated from this active region seem to be involved with the interaction of two magnetic field systems characterized by opposite signs of helicity.

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Numerical Study on the Air-Cushion Unit for Transportation of Large-Sized Glass Plate

  • Jun, Hyun-Joo;Kim, Kwang-Sun;Im, Ik-Tae
    • 반도체디스플레이기술학회지
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    • 제6권1호
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    • pp.59-64
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    • 2007
  • Non-contact transportation of a large-sized glass plate using air cushion for the vertical sputtering system of liquid crystal display (LCD) panel was considered. The objective of the study was to design an air pad unit which was composed of multiple injection and exhaust holes and mass flow supplying pipe. The gas was injected through multiple small holes to maintain the force for levitating glass plate. After hitting the plate, the air was vented through exhaust holes. Complex flow field and resulting pressure distribution on the glass surface were numerically studied to design the air injection pad. The exhaust hole size was varied to obtain evenly distributed pressure distribution at fixed diameter of the injection hole. Considering the force for levitating glass plate, the diameter of the exhaust hole of 30 to 40 times of the gas injection hole was recommended.

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LDM-MIMO ATSC 3.0 방송 시스템의 Core-Layer 신호를 위한 저복잡도 HPGA 복호 기법들 (Low-Complexity HPGA Decoding Methods for Core-Layer Signal in LDM-MIMO ATSC 3.0 Broadcasting Systems)

  • 김승현;;정태진
    • 방송공학회논문지
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    • 제27권1호
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    • pp.146-149
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    • 2022
  • 본 레터는 Layered-Division-Multiplexing Multiple-Inputs-Multiple-Outputs ATSC 3.0 방송 시스템의 Core-Layer신호에 대한 저복잡도 Hybrid-Partial-Gaussian-Approximation(HPGA) 복호 기법들을 제안하고자 한다. 제안된 HPGA 기법들은 각 수신 안테나 신호의 Injection-Level 값에 따라 기존의 제안된 GA 및 PGA 기법들을 선택적으로 사용하여 기존의 PGA 기법에 비해 큰 성능 저하 없이 복호 복잡도를 크게 줄일 수 있는 장점을 갖는다.

군정의 주입량의 정밀 제어를 위한 유량조절밸브의 개도 및 최소 펌프 소요양정 (Valve Openings and Minimum Pump Head for Precise Operation of Multiple Groundwater Injection Wells)

  • 박남식;장치웅;조광우
    • 한국수자원학회논문집
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    • 제48권10호
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    • pp.869-877
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    • 2015
  • 해수침투 방지나 대수층 인공함양을 위하여 다수의 관정을 통하여 대수층으로 물을 주입하는 공법이 있다. 이러한 공법의 경우 소기의 목적을 달성하기 위해서는 관정의 위치와 주입량, 그리고 결과되는 관정의 지하수위 등이 별도의 지하수 모델링을 통하여 결정된다. 주입수는 통상 관망을 통하여 관정으로 공급되는 데 이 때 관망에는 관정별 주입량을 조절하기 위한 밸브가 설치된다. 본 연구에서는 다수의 주입 관정이 연결된 관망에서 사전에 산정된 주입량 분포를 준수하기 위한 밸브 개도와 주입관망 가동에 필요한 펌프 최소 소요양정 산정방안을 제시하였다. 본 연구결과는 주입군정 운영의 정밀도를 향상시키는 데 기여할 수 있다.

낙뢰 간접영향에 대한 항공전자장비의 환경시험 (Environmental Test of Avionics Equipment for Lightning Indirect Effect)

  • 정덕영;양현덕
    • 항공우주시스템공학회지
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    • 제7권2호
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    • pp.55-59
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    • 2013
  • Before avionics equipment are installed in aircraft, several environmental tests such as temperature, vibration, lightning, fire etc. must be conducted. One of the environmental tests is to substantiate protection designs of lightning indirect effect. It can be showed through RTCA DO-160G, section22 "Lightning Induced Transient Susceptibility" test. An additional test of aircraft level is required as well after installation of avionics equipment.

Characteristics of Semiconductor Laser Using Optical Injection Locking Scheme

  • Kim, Jung-Tae
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2004년도 SMICS 2004 International Symposium on Maritime and Communication Sciences
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    • pp.66-69
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    • 2004
  • We have investigated the spectral characteristics of semiconductor lasers locked to the external light injected from a modulated laser. The numerical model for semiconductor lasers under the external optical injection is based on the Lang's equation and has been extended in order to take into account the simultaneous injection of the multiple sidebands of the current-modulated laser. In this paper, we have analyzed characteristics of semiconductor laser using optical injection locking

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성대주입에 의한 성대수술 -수술수기 및 주입물질을 중심으로- (Phonosurgical Vocal Fold Injection)

  • 최홍식;김성수
    • 대한후두음성언어의학회지
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    • 제12권1호
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    • pp.5-10
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    • 2001
  • 성대 내 주입에 의한 음성수술은 적절한 접근방법을 통해 적절한 주입물을 선택한다면 여러가지 음성장애에 대한 매우 우수한 치료중의 하나이다. 자가지방이 성대내주입술과 내시경적 성대내주입술은 최근에 개발된 수술방법이다. 성대 내 주입물질을 다룰 때 반드시 세심한 주의를 기울여야하고, 환자의 요구에 맞게 환자의 현 상태에 가장 적합한 주입물을 선택하도록 하여야 하며, 시술 시에는 주입하려고 하는 정확한 위치에 주입하여야 한다.

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다재 사출성형 전문가 시스템 개발 (Development of an Expert System for Multi-component Injection Molding)

  • 강신일
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1999년도 춘계학술대회논문집
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    • pp.213-217
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    • 1999
  • An expert system is developed for rational and efficient design of multi-component injection molding which is a fairly new manufacturing technique to produce plastic parts by injecting two or more materials sequentially using multiple injection units in a single machine into a single rotary mold. The knowledge base used in the present design system is primarily composed of two parts ; knowledge from domain expert and knowledge from CAE analysis. The present expert system has hour main modules ; general design guidelines for injection molding specific guidelines for multi-component injection molding redesign guidelines from the result of the CAE analysis and finally troubleshooting for multi-component injection molding. To show the validity of the present design methodology two shop floor design problems were tested ; design and fabrication of timing belt cover and power window's assist knob by using multi-component injection molding.

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쌍대비교에 기초한 다속성 효용함수의 결정 및 사출성형설계에 대한 응용 (Determination of a Multiattribute Utility Function Based on the Pairwise Comparison and the Application to Injection Molding Design)

  • 박종천;김경모
    • 소성∙가공
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    • 제12권5호
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    • pp.465-472
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    • 2003
  • Engineering design can be viewed as a decision making process, which involves the nonlinear tradeoffs task among the multiple conflicting attributes and considers the robustness of design. In order to obtain best engineering design, methodology for accurate assessment of his/her preference about the multiple attributes is required. Conventionally, intuitive procedures based on lottery questions are used to elicit the designer's preference structure: however, they can lead to inconsistent and inexact preference results due to the rank reversal problems derived from the designer's big cognitive burden. In this paper, alternatively, a design methodology based on multiattribute utility function through the pairwise comparison among alternatives is presented. The proposed procedure is applied to an actual injection mold design with the aid of the CAE simulation and the result is discussed.

AMESim기반 CRDi용 인젝터의 2단분사 동적거동 특성해석 (Analysis of Dynamic Characteristics in Two-stage Injection for CRDi Injectors Based on AMESim Environment)

  • 조인수;권지원;이진욱
    • 한국분무공학회지
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    • 제17권2호
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    • pp.57-63
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    • 2012
  • For reduction of CO, NOx and soot emission emitted by diesel diffusion combustion, the authors focused on injection actuator to improve fuel availability inside combustion chamber. In this study, it was investigated the internal dynamic characteristics of two-stage injection with diesel injectors with different driving type for the common rail direct injection by using the AMESim simulation code. The analysis parameter defined such as fuel pressure, injection hole's diameter and driven voltage. As the results, it was shown that the piezo-driven injector had a faster response and had better control capability than the solenoid-driven injector. It was found the piezo-driven injector can be utilized effectively as multiple injector than solenoid-driven injector.