• 제목/요약/키워드: engineering technique

검색결과 22,457건 처리시간 0.042초

A Developing Approach of 600 W SHF TWTA for Communications Using Cathode Ripple Reduction Technique

  • Hong, In-Pyo
    • Journal of electromagnetic engineering and science
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    • 제8권3호
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    • pp.119-128
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    • 2008
  • In this paper, we propose a developing approach of 600 W super high frequency(SHF) traveling wave tube amplifier (TWTA) for communications. Also, we make a TWTA called the experimental-TWTA(ETWTA), which uses a cathode ripple reduction technique to improve RF performance. After implementation, we discuss, and compare it with some other TWTAs. Its RF performance is better than that of other TWTAs. Therefore, this methodology can be used to develop the high power SHF TWTA for communications.

A Study on the Control of Vehicle Suspension by using Electro-Rheological Fluid via FLC Technique (FLC를 이용한 전기유전유체를 사용한 차량현가장치의 제어에 관한 연구)

  • Kim, Haak-Kyun;Heo, Hoon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 한국소음진동공학회 1996년도 춘계학술대회논문집; 부산수산대학교, 10 May 1996
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    • pp.203-208
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    • 1996
  • This paper consider the control for the vehicle suspension system using electro-rheological damper. The study is performed by using of FLC(Fuzzy Logic Controller). The model used in the simulation is quarter car and the road disturbance is regarded as white noise random process with zero mean. Proposed control technique shows good agreement compared with the result from the conventional on-off/bang-bang type control technique.

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Improved Viewing Quality of 3-D Images in Computational Integral Imaging Reconstruction Based on Lenslet Array Model

  • Shin, Dong-Hak;Lee, Byoung-Ho;Kim, Eun-Soo
    • ETRI Journal
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    • 제28권4호
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    • pp.521-524
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    • 2006
  • In this letter, we propose a novel computational integral imaging reconstruction technique based on a lenslet array model. The proposed technique provides improvement of viewing images by extracting multiple pixels from elemental images according to ray tracing based on the lenslet array model. To show the feasibility of the proposed technique, we analyze it according to ray optics and present the experimental results.

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Linearized Modeling Technique for Complex Dynamic Responses Using Proper Orthogonal Decomposition (적합직교분해법을 이용한 복잡한 동적응답의 선형화 모델링 기법)

  • Lee, Soo-Il;Hong, Sang-Hyuk
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 한국소음진동공학회 2008년도 춘계학술대회논문집
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    • pp.156-159
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    • 2008
  • Proper orthogonal decomposition is a statistical pattern analysis technique for finding the dominant components, called the proper orthogonal modes, in ensembles of spatially distributed data. We present recent ideas based on proper orthogonal decomposition (POD) and detailed experiments that yield new perspectives into the microscale structures. The linearized modeling technique based on POD is very useful to show the principal characteristics of the complex dynamic responses.

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A Split Time-Ratio Gray Scale Diving Technique for AMOLED Displays

  • Gupta, Mayank.Prakash.;Mazhari, B.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.1347-1350
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    • 2005
  • A modified Time-Ratio Gray Scale AMOLED drive technique is described in which the frame period is split into two half-frames, each of which is divided into binary weighted sub-frames and driven in the conventional time-ratio manner. The proposed technique improves aperture ratio by reducing TFT sizes in pixel circuits.

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Importance Sampling Technique for System Reliability Analysis of Bridge Structures (교량구조의 체계 신뢰성 해석을 위한 중요도 표본추출 기법)

  • 조효남;김인섭
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 한국전산구조공학회 1991년도 봄 학술발표회 논문집
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    • pp.34-42
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    • 1991
  • This study is directed for the development of an efficient system-level Importance Sampling Technique for system reliability analysis of bridge structures Many methods have been proposed for structural reliability assessment purposes, such as the First-order Second-Moment Method, the Advanced Second-Moment Method, Computer Simulation, etc. The Importance Sampling Technique can be employed to obtain accurate estimates of the required probability with reasonable computation effort. Based on the observation and the results of application, it nay be concluded that Importance Sampling Method is a very effective tool for the system reliability analysis.

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Non-Contacted Strain Analysis by Dual-beam Shearography (변형 해석을 위한 Dual-beam Shearography)

  • 김경석;정성욱;장호섭;최태호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.400-403
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    • 2002
  • This paper presents a shearographic technique for measuring in-plane strains. During the measurement, the test object is illuminated alternately with two laser beams, symmetrically with respect to the viewing direction. Employing a phase shift technique, the phase distributions due to object deformation for each beam are obtained separately. The difference of the two phase distributions depicts the derivative of in-plane surface displacements. The technique is equivalent to a system of many strain gages.

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A Study on the Classification of Inventory Items (재고품목의 분류에 관한 연구)

  • 이상도;이강우
    • Journal of Korean Society of Industrial and Systems Engineering
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    • 제13권21호
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    • pp.61-72
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    • 1990
  • In the past, a fundamental technique in inventory control system was to rank the items of a inventory from a distribution by value to draw an ABC curve. Unfortunately the use of ABC categorization technique has created problems and introduced some gross errors into the inventory control system. First, the author considers the possible applications of the technique in the real world and then attempts to discuss ABC fallacies through the literatures. Finally, an inventory categorization algorithm by the principal component analysis is derived and a numerical example is also presented to illustrate the algorithm.

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Computation of Equivalent Material Properties of Woven Fabric Composites Using Homogenization Technique (균질화기법을 이용한 WFC의 등가물성치 산출)

  • 이진희;장지현;윤민우
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 한국전산구조공학회 1997년도 가을 학술발표회 논문집
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    • pp.1-7
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    • 1997
  • Equivalent thermal conductivities and elasticity properties of woven fabric composites are computed using homogenization technique. The computational results show that the strength and thermal conductivity linearly increase with fiber volume fraction and that the variations of undulation of fibers has little effect on equivalent material properties. Homogenization technique is proved useful in the study of woven fabric composites and may find a lot more applications in the area.

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A study on the generation of SMD mounting position and orientation utilizing image processing technique (영상처리 기법을 이용한 SMD 장착위치 및 방향 생성에 관한 연구)

  • 구영모
    • Journal of Korean Society of Industrial and Systems Engineering
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    • 제22권50호
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    • pp.11-21
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    • 1999
  • In this paper, an algorithm to generate the mounting position and orientation of SMD is proposed. For the proposed algorithm, we used the image captured from PCB and utilized image processing technique. Pre-processing technique, threshold level determination method, divided recognition of the SMD pattern on a PCB, calculating mounting position and orientation are related topics of this research. All of the related topics were reviewed and the results of this research were obtained from applying the algorithm to the real Surface Mounting Machine(model:MCUl/CPM) made by Samsung Electronics Co.

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