• Title/Summary/Keyword: Fringe

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Absolute phase identification algorithm in a white light interferometer using a cross-correlation of fringe scans (백색광 간섭기에서 간섭 무늬의 상호 상관관계 함수를 이용한 절대 위상 측정 알고리즘)

  • Kim, Jeong-Gon
    • Journal of Sensor Science and Technology
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    • v.9 no.4
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    • pp.316-326
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    • 2000
  • A new signal processing algorithm for white light interferometry has been proposed and investigated theoretically. The goal of the algorithm is to determine the absolute optical path length of an interferometer with very high precision (<< one optical wavelength). The algorithm features cross-correlation of interferometer fringe scans and hypothesis testing. The hypothesis test looks for a zero order fringe peak candidate about which the cross-correlation is symmetric minimizing the uncertainty of misidentification. The shot noise limited performance of the proposed signal processing algorithm has been analyzed using computer simulations. Simulation results were extrapolated to predict the misidentification rate at Signal to-Shot noise ratio (SNR) higher than 31 dB. Root-mean-square phase error between the computer-generated zero order fringe peak and the estimated zero order fringe peak has been calculated for the changes of three different parameters (SNR, fringe scan sampling rate, coherence length of light source). Results of computer simulations showed the ability of the proposed signal processing algorithm to identify the zero order fringe peak correctly. The proposed signal processing algorithm uses a software approach, which is potentially inexpensive, simple and fast.

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An Efficient 3D Measurement Method that Improves the Fringe Projection Profilometry (Fringe Projection Profilometry를 개선한 효율적인 3D 측정 기법)

  • Kim, Ho-Joong;Cho, Tai-Hoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.10
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    • pp.1973-1979
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    • 2016
  • As technologies evolve, diverse 3D measurement techniques using cameras and pattern projectors have been developed continuously. In 3D measurement, high accuracy, fast speed, and easy implementation are very important factors. Recently, 3D measurement using multi-frequency fringe patterns for absolute phase computation has been widely used in the fringe projection profilometry. This paper proposes an improved method to compute the object's absolute phase using the reference plane's absolute phase and phase difference between the object and the reference plane. This method finds the object's absolute phase by adding the difference between the reference plane's wrapped phase and the object's wrapped phase to the reference plane's absolute phase already obtained in the calibration stage. Through this method, there is no need to obtain multi-frequency fringe patterns about new object for the absolute phase computation. Instead, we only need the object's phase difference relative to the reference planes's phase in the measurement stage.

Land Use Management Issues of the Urban Fringe in the UK

  • Kim, Soo-Bong;Kim, Yong-Bum;Jung, Eung-Ho
    • Journal of Environmental Science International
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    • v.12 no.5
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    • pp.511-519
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    • 2003
  • It is difficult to define the urban fringe using a specific geographical designation in the physical planning system because the existence of the urban fringe is certainly not equal in all directions from the inner urban area to the rural area, and is often a discontinuous spatial phenomenon from the inner fringe to the urban shadow. Nevertheless, the urban fringe raises land use management issues which stem from its own peculiar set of land use characteristics. For example, in the UK, how the public can enjoy access to the countryside in the urban fringe while at the same time recognising and acknowledging the importance of landowners and farmers property rights\ulcorner how can a poor quality environment and degraded landscape be improved aesthetically and physically to meet the multiple recreational needs of a diverse population when local authorities are confronted with limited ability to fund and acquire land for these purposes\ulcorner The challenge of addressing these land use management issues necessitates approaches which build a coalition of interest groups and public and non-government organizations in the management processes in order to improve the physical, economic and social environments and facilitate the management mechanism.

Fringe Field Effects on Transient Characteristics of Nano-Electromechanical (NEM) Nonvolatile Memory Cells

  • Han, Boram;Choi, Woo Young
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.5
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    • pp.609-614
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    • 2014
  • The fringe field effects on the transient characteristics of nano-electromechanical (NEM) memory cells have been discussed by using an analytical model. The influence of fringe field becomes stronger as the size of a cell decreases. By using the proposed model, the dependency of NEM memory transient characteristics on cell parameters has been evaluated.

A Study on the Automatic Routing Using FRINGE (FRINGE를 이용한 자동배선에 관한 연구)

  • 박노경;전흥우;차균현
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.6
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    • pp.1034-1039
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    • 1987
  • In this paper, an automatic routing algorithm using Fringe is described. The concept of the Fringe is very simple, but it provides a powerful and flexible tool for doing single layer routing. The automatic routing program is coded using C language, and implemented on a VAX11/750 and IBM -PC AT computer. The usefulness of the routing algorithms is shown by the execution of the program on some examples.

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Material Stress Fringe Constant Measurement of Specimen under Pure Bending Load by Use of Photoelastic Phase Shifting Method (광탄성 위상이동법을 이용한 순수굽힘보 시편의 재료 응력 프린지 상수 측정)

  • Liu, Guan Yong;Kim, Myung Soo;Baek, Tae Hyun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.38 no.12
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    • pp.1387-1394
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    • 2014
  • In a photoelastic experiment, it is necessary to know the material stress fringe constant of the photoelastic specimen to determine the stresses from the measured isochromatic fringe orders. The material stress fringe constant can be obtained using a simple tension specimen and/or a circular disk under diametric compression. In these methods, there is generally a need to apply numerous loads to the specimen in response to the relationship of the fringe order. Then, the least squares method is used to obtain the material constant. In this paper, the fringe orders that appear on a four-point bending specimen are used to determine the fringe constant. This method requires four photoelastic fringes obtained from a circular polariscope by rotating the analyzer to 0, ${\pi}/4$, ${\pi}/2$, and $3{\pi}/4$ radians. Using the four-point bending specimen to determine the material stress fringe constant has an advantage because measurements can be made at different locations by applying a constant load. The stress fringe constant measured with this method is within the range suggested by the manufacturer of the photoelastic material.

A Study on the Correlation Results for Fringe Rotation and Delay Tracking of the VCS (VCS의 지연추적과 프린지 회전에 대한 상관결과 고찰)

  • Oh, Se-Jin;Yeom, Jae-Hwan;Roh, Duk-Gyoo;Oh, ChungSik;Jung, Jin-Seung;Chung, Dong-Kyu;Oyama, Tomoaki;Kawaguchi, Noriyuki;Kobayashi, Hideyuki;Kono, Yusuke;Ozeki, Kensuke;Onuki, Hirohumi
    • Journal of the Institute of Convergence Signal Processing
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    • v.13 no.4
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    • pp.220-232
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    • 2012
  • In this paper, we investigate the correlation result due to the problems of delay tracking and fringe rotation module in the VCS(VLBI Correlation Subsystem). The VCS, FX-type correlator, adopts the delay tracking and fringe rotation module in order to compensate the delay change and fringe phase of wave signal from the radio source by Doppler's effect. The phase of observed data is also compensated by means of delay tracking and fringe rotation in the correlator, but we confirmed that the phase is unstable by applying long integration period of AIPS(Astronomical Image Processing System) rather than correlator. And the delay value of observed data has the errors of several tens nanoseconds than normal case at the analysis of correlation result. In addition, we found that the phase of correlation results is not connected as the unit of FFT-segment because the initial fringe phase at the fringe rotation module is not correctly determined. In this paper, in order to solve these problems, the original direction of 90 degree phase jump is reversely modified when the bit-shift occurred at the delay tracking. And the initial fringe phase at the fringe rotation module is correctly modified by using the initial phase of observed data. In addition, the parameter calculation module was abnormally operated as designed in the fringe rotation. So, the logical program by the VCS is modified so as to calculate the parameters correctly. Through the experiments of correlation processing over the above problems, the modified proposal algorithm is adequately corrected to the data analysis results, so that the experimental results make it clear for us to operate the developed VCS hardware correlator normally.

A study on the expression types and aesthetic formativeness of tassels and fringe in modern bag design (현대 가방 디자인에 나타난 술 장식의 표현유형과 미적 조형성 연구)

  • Kwon, Giyoung
    • The Research Journal of the Costume Culture
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    • v.28 no.4
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    • pp.429-445
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    • 2020
  • The purpose of this study is to provide ideas for the development of bag design by analyzing the expression types and aesthetic formativeness of modern bag design using tassels and fringe given the newtro trend pursuing analog sensitivity in modern society. The methods and scope of this study are as follows. First, the related literature and internet data were reviewed in order to examine the expression types and characteristics of the bags of the West and East. Next, the definition and characteristics of tassel and fringe decoration in terms of the history of clothing were analyzed. Finally, the expression types and aesthetic formativeness of tassels and fringe were derived through the analysis of modern bag design shown in the fashion collections since 2010. The bags decorated with the tassels and fringe bring a variety of visual effects depending on the attachment position, direction and material composition, concentrating the gaze and radiating original style. In this study, the expression of tassels and fringe in modern bag design was classified into three types: surface decoration, shape variability, and object combination. Next, the aesthetic formativeness of modern bag design using tassels and fringe as decorative elements appeared through the mixture of heterogeneous materials and playfulness through imagination, exaggeration through extension of length and volume, and retro characteristics through reinterpretation of tradition. This study is expected to contribute to creative ideas of modern bag design which requires a global sense, which has been used in various cultures for a long time.

Deformation Measurement of Electronic Components in Mobile Device Using High Sensitivity Shadow Moiré Technique (고감도 그림자 무아레 기법을 이용한 모바일 전자부품의 변형 측정)

  • Yang, Hee-Gul;Joo, Jin-Won
    • Journal of the Microelectronics and Packaging Society
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    • v.24 no.1
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    • pp.57-65
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    • 2017
  • The electronic components in mobile device are composed of electronic chips and various other materials. These components become extremely thin and the constituent materials have different coefficient of thermal expansion, so that considerable warpages occurs easily due to temperature change or external load. Shadow $moir{\acute{e}}$ is non-contact, whole field technique for measuring out-of-plane displacement, but the measurement sensitivity is not less than $50{\mu}m/fringe$, which is not suitable for measuring the warpage of the electronic components. In this paper, we implemented a measurement method with enhanced sensitivity of $25{\mu}m/fringe$ by investigating and optimizing various experimental conditions of the shadow $moir{\acute{e}}$. In addition, four $moir{\acute{e}}$ fringe patterns recorded by the phase shift are processes to obtain a $moir{\acute{e}}$ fringe patterns with a sensitivity four times higher. The measurement technique is applied to small electronic components of a smart phone for measuring warpage with a high sensitivity of $5{\mu}m/fringe$ at room temperature and at the temperature of $100^{\circ}C$.

Development of Integrated fringe Analysis System: For Severe Noise-ridden Interferometric Image Analysis (통합 프린지 해석 시스템 개발 : 심한 잡음을 포함하는 간섭 이미지 해석용)

  • Kang, Min-Gu;Joo, Won-Jong;Cha, Dong-Jin;Kang, Bo-Sun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.11
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    • pp.1534-1541
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    • 2003
  • A new window-based, user-friendly fringe analysis system is developed, especially for analyzing noisy interferograms. The system integrates three major techniques, that is fringe tracking, Phase shifting, and Fourier transform, into a single shell by employing a unified procedure. Since the system is made in a modular fashion and all processing modules can be shared for any technique, a user can select necessary modules and easily edit the applying order of them based on the user's analysis strategy, which should be changed depending on the noise level of the image. The system provides a high-level GUI and a variety of image handling tools and therefore users can easily access the system and produce the optimal results without giving up in the middle of a process even for severely noise-contaminated interferometric images.