• Title/Summary/Keyword: fringe

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Speckle Interferometry and Automatic Fringe Analysis for Small Displacement Measurement (미세변위 측정을 위한 스펙클 간섭계의 구성과 자동 Fringe 해석)

  • 김성근;길상근;박한규
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.8
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    • pp.1282-1289
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    • 1989
  • Dual field speckle interferometry that is sensitive to the surface displacement of the object is constructed, and fringe patterns that have the displacement-informations are analysed using digital image processing. From 10\ulcorner to 80\ulcorner with respect to each specklegrams are obtained by double-exposure techniques, which are analysed by the proposed system and algorithm. Up to 10\ulcorner displacement, near measurable lower bound of Speckle Interferometry, fringe visibility is decreased due to decreasing fringe density, therefore relative errors are produced over 10% but over that displacement, relative errors are produced below 5%. Particularly, it is observed that spatial frequencies of each displacement are comparatively linear.

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Development of Image Processing Technique for Photoelastic Fringe Analysis (광탄성 프린지해석을 위한 영상처리기법 개발)

  • 백태현;이재춘
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.10
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    • pp.2577-2584
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    • 1994
  • A method of digital image processing thechnique, which can multiply and sharpen isochromatic fringes in photoelasticity on both occasions, is developed. To test the method, photoelastic fringe patterns of a disk compressed by two diametrically opposite cocentrated loads are simulated and these patterns are processed to yield sharpened lines. The method is then aplied to measurement of residual stresses in glass bar. The procedure is proved to be capable of extraction sharpened lines accurately from photoelastic multiplied fringes, and yields good experimental results consistently and precisely.

Simulation for Electro-Optic Characteristics of the Fringe-Field Driven Reflective Hybrid Aligned Nematic Liquid Crystal Display with One Polarizer (1매의 편광판으로 구성된 Fringe-Field 구동형 반사형 Hybrid Aligned Nematic 액정디스플레이의 전기-광학 특성에 관한 시뮬레이션)

  • 박지혁;정태봉;이종문;김용배;이승희
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.10
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    • pp.908-913
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    • 2003
  • We have performed computer simulation to obtain electro-optic characteristics of reflective hybrid aligned nematic liquid crystal displays (LCDs) driven by fringe field. The results show that the optimal retardation value (dΔn) of the cell is 0.289 ${\mu}$m, which allows for the cell to have a practical cell gap of larger than 3 ${\mu}$m when manufacturing. A reflectance of the dark state is only 0.114 % for an incident light 550 nm. At this condition, the light efficiency of white state reaches 92.7 %. The display with optimized cell parameters shows that the contrast ratio greater than 5 exists over 600 of polar angle in all directions and lower driving voltage than that of fringe-field driven homogeneously aligned reflective LCD.

Study on transmittance improvement of 90 twisted nematic liquid crystal display driven by fringe-electric frield (Fringe 전기장 구동 Twisted Nematic 액정 디스플레이의 투과율 향상 연구)

  • Ryu, Je-Woo;Lee, Ji-Youn;Lim, Young-Jin;Jeon, Yeon-Mun;Lee, Seung-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.06a
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    • pp.446-447
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    • 2006
  • We investigated the electro-optic characteristics of a fringe-field driven twisted nematic (TN) display using a LC with negative dielectric anisotropy depending on electrode structures. The fringe-field driven TN mode known to exhibit wide viewing angle and excellent color characteristics over a wide viewing range and high transmittance. However, when the electrode width and distance between them is large enough, the transmittance is lower than the conventional vertical field-driven TN mode. By narrowing the electrode width and distance, the transmittance reaches the same value of the conventional TN mode.

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Phase calcuation error analysis of 3D shape measurement system using phase-shifted fringe projection method (위상이동 간섭무늬 투영을 이용한 3차원 형상측정 시스템의 위상계산오차 해석)

  • 류현미;김석성;홍석경;연규황
    • Korean Journal of Optics and Photonics
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    • v.13 no.3
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    • pp.182-188
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    • 2002
  • We have analyzed the phase-calculation-error of a three-dimensional shape measurement system using the projection of phase shifted fringe patterns. In this study, we have dealt various errors; an error caused by the variation of quantization levels, an error caused by the defocus of fringe pattern projected images, an error caused by phase-shifting errors, an error caused by the intensity variation of the background and modulation amplitude of fringe pattern projected images during the projection of multiple patterns, an error caused by the distortion of sinusoidal shape of a fringe pattern. The results will contribute to the design of a three-dimensional shape measurment system and give an important meaning to the calculation and the analysis of the accuracy of a system.

Electro-Optic Characteristics according to Distance between Pixel Electrodes in Fringe In-plane field Switching mode (화소 전극 간 거리가 Fringe In-plane field Switching mode의 전기 광학 특성에 미치는 영향)

  • Kim, Min-Su;Park, Ji-Woong;Jung, Jun-Ho;Ha, Kyung-Su;Lim, Young-Jin;Lee, Myong-Hoon;Lee, Seung-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.337-338
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    • 2008
  • We have studied electro-optic characteristics of a high performance liquid crystal display using Fringe In-plane field Switching (FIS) mode. The strong electric fields cause more liquid crystals to reorient almost in plane above and between the pixel electrodes. As a result, the operation voltage is lower and transmittance is higher than those of Fringe Field Switching (FFS) and In-Plane Switching (IPS) modes. Apparently, the transmittance depends on voltage applied at the configurations of FIS mode which are proposed. Therefore, we have studied certain length of between electrodes for maximum transmittance and light intensity.

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A Study on the Small Disturbance Measurement of Liquid Film Thickness by $Moir\acute{e}$ Fringe ($Moir\acute{e}$ Fringe에 의한 액막 두께 미소 변위 측정 연구)

  • Jeon, H.S.;Kim, K.H.
    • Journal of ILASS-Korea
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    • v.2 no.4
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    • pp.29-35
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    • 1997
  • Liquid film thickness is measured by $moir\acute{e}$ topography which monitored liquid surface. $Moir\acute{e}$ fringe measurement techniques share the inherent simplicity found in optical interferometric techniques have the advantage of use over a greater range of displacement. $Moir\acute{e}$ fringe are the geometric interference patterns observed when two dense line grating are superposed. Light transmitted through a fixed line grating is deviated by the liquid film surface, producing a distored image of the grating. The $moir\acute{e}$ fringe produced by projection of this optically distored grating onto a second stationary grating permit visualization of the liquid surface and measurement of the liquid film thickness. This study measured the small amplitude of liquid film thickness to the $moir\acute{e}$ fringe pattern produced when spherical metal was dropped glycerin put)1 And the measurement of liquid film thickness flowing down an inclined plate are required to calculate the liquid slope in a position.

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Evaluating Employee Fringe Benefits Provided by the Entrepreneurs in BSCIC Industrial Estates

  • Md. Mokarremul Hoque Helal MRIDHA;Md. KAMRUZZAMAN;Md. Alamgir HOSSAIN;Renhong WU
    • Asian Journal of Business Environment
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    • v.13 no.4
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    • pp.7-17
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    • 2023
  • Purpose: The objective of this study is to evaluate the fringe benefits provided by the entrepreneurs in BSCIC (Bangladesh Small and Cottage Industries Corporation) industrial estates in light of the relevant labor laws of Bangladesh. Research question: Fringe benefits are one of the major factors in compensation that play a vital role in employee satisfaction. However, the issue has yet to be taken into consideration in the industrial units. So, the question arises: what is the present condition of employee fringe benefits in industrial estates? Research design, data, and methods: To conduct this mixed-methods research, a total of 222 respondents were selected randomly from employees and entrepreneurs. Two sets of self-administered questionnaires and KIIs were used to collect primary data, while SPSS was used to analyze the data. Major findings and conclusions: The study shows that the conditions of leave and holidays do not comply with labor laws. Further, aspects of maternity leaves, disability/death benefits, retirement benefits, and other financial and non-financial benefits are found not to be at a satisfactory level and do not comply with the existing labor laws. However, the benefits relating to environmental issues are found to be satisfactory. It is expected that the study findings will contribute to the existing literature related to fringe benefits and will help stakeholders and policymakers in formulating and monitoring compensation packages.

An Analysis of the Urban Fringe Management Initiative's Operational Process in UK Using the Actor Network Theory - A Case Study of Thames Chase Community Forest Initiative - (행위자연계망이론을 통한 영국 도시교외지역 관리시책의 운영과정 특성 분석 -테임즈 체이스 마을 숲 조성 시책을 사례로-)

  • Kim, Yong-Bum;Park, Jae-Hong;Chun, Sung-Hwan
    • Journal of Korean Society of Rural Planning
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    • v.13 no.1 s.34
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    • pp.97-109
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    • 2007
  • The purpose of this research was to investigate and analyse how Community Forest Initiatives as urban fringe management initiatives made alliances with a variety of interest groups, enrol them in the urban fringe management processes using the Actor Network Theory. The Thames Chase Community Forest Initiative was selected and its area of operation included a $97 km^2$ area of green-belt area in East London. It was a instrument far improving and protecting the unique characteristics of the countryside landscape from urban developments as well as evaluating the impact of forestry inclusion in land use planning in the urban fringe. It was operated through a tiered structure comprising the Thames Chase Joint Committee and the management team. They employed a variety of devices to speak with one voice to bring about an effective operation process and to secure the enrolment of a variety of interest groups in its operational processes. Of note, the initiative's actor network impacted on improvement to and management of the countryside landscape despite not owning any land itself. As a result, when urban fringe management initiatives will be launched in South Korea to achieve a more effective and efficient urban fringe management, local councillors and representatives from public and non-government bodies should be more responsive to local communities' views and needs and work more vigorously on their behalf through lobbying, seeking media support, and so on. Moreover, better understanding and communication between local authorities' officers and management initiatives' teams are essential to avoid duplication of work practice.

Measurement of Isochromatic Fringe Distribution of a TV Glass Panel by Use of Photoelastic 4-step Phase Shifting Method (광탄성 4단계 위상이동법을 이용한 TV유리패널의 등색프린지 분포측정)

  • Baek, Tae-Hyun;Kim, Myung-Soo;Cho, Seong-Ho
    • Journal of the Korean Society for Nondestructive Testing
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    • v.25 no.1
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    • pp.1-8
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    • 2005
  • This paper presents the experimental results measured by photoelastic 4-step phase shifting method for the isochromatic fringe distribution in a TV glass panel. In the conventional photoelastic method, the isochromatic fringe orders are measured manually point by point. The 4-step phase shifting method uses four images obtained from a circular polariscope by rotating the analyzer to $0^{\circ},\;45^{\circ},\;90^{\circ}$, and $135^{\circ}$. In order to use the 4-step phase shifting method, the elements of a polariscope should be aligned to isoclinic direction at a point and/or along a line where isochromatic fringe distribution is measured. Experimental results obtained from the 4-step phase shifting method are compared with those measured by the Senarmont compensation method. Both results are well agreed. Then, isochromatic fringe distributions in the TV glass panel that is heat-treated before and after are compared. Maximum and minimum isochromatic fringe orders in the TV glass panel with before- and after-heat treatment are changed approximately two times.