• 제목/요약/키워드: fringe analysis

검색결과 239건 처리시간 0.028초

홀로그래피 간섭계를 이용한 미소변위 측정 (Small Displacement Measurement by Holographic Interferometry)

  • 이해중;황운봉;박현철
    • 대한기계학회논문집
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    • 제16권5호
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    • pp.864-872
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    • 1992
  • 본 연구에서는 이중노출 홀로그래피 간섭계의 원리를 이용하여 임의의 2차원 적 변형에 있어서 면외 변위와 면변위(in-plane displacement) 각각에 대한 홀로그램 을 제작하고 이를 컴퓨터에 입력하여 간섭무늬를 해석함으로써 변위와 변형률의 정량 화를 시도하였다.

AN INTERFERENCE FRINGE REMOVAL METHOD BASED ON MULTI-SCALE DECOMPOSITION AND ADAPTIVE PARTITIONING FOR NVST IMAGES

  • Li, Yongchun;Zheng, Sheng;Huang, Yao;Liu, Dejian
    • 천문학회지
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    • 제52권2호
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    • pp.49-55
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    • 2019
  • The New Vacuum Solar Telescope (NVST) is the largest solar telescope in China. When using CCDs for imaging, equal-thickness fringes caused by thin-film interference can occur. Such fringes reduce the quality of NVST data but cannot be removed using standard flat fielding. In this paper, a correction method based on multi-scale decomposition and adaptive partitioning is proposed. The original image is decomposed into several sub-scales by multi-scale decomposition. The region containing fringes is found and divided by an adaptive partitioning method. The interference fringes are then filtered by a frequency-domain Gaussian filter on every partitioned image. Our analysis shows that this method can effectively remove the interference fringes from a solar image while preserving useful information.

Current taxonomic status of Eurema mandarina (Pieridae: Lepidoptera) in Korea

  • Kim, Sung-Soo;Choi, Sei-Woong;Park, Jeong Sun;Kim, Iksoo
    • International Journal of Industrial Entomology and Biomaterials
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    • 제43권1호
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    • pp.6-15
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    • 2021
  • We investigated the taxonomic status of the Korean populations of Eurema hecabe (Linnaeus, 1758) based on morphology and nuclear triose phosphate isomerase (Tpi). Up to now, the Korean population of E. hecabe was classified into E. mandarina (de l'Orza, 1869) based on morphological characteristics. A previous study raised the possibility of the Jeju-do population to be E. hecabe based on the color of forewing's fringe. However, morphological examination showed that the Korean population found in southern areas (Gyeonsang and Jeolla provinces), including Jeju-do is E. mandarina. In particular, the external morphology of autumn seasonal type of the Korean population was almost same as the Japanese mainland population, which is known as E. mandarina. Furthermore, sequence analysis of Tpi gene from nine individuals of E. mandarina collected in South Korean localities including Jeju-do clearly showed that all Korean specimens truly belong to E. mandarina.

Morphological and Molecular Characterization of Pseudocercospora chionanthi-retusi Causing Leaf Spot on Chionanthus retusus in Korea

  • Choi, In-Young;Abasova, Lamiya;Choi, Joon-Ho;Shin, Hyeon-Dong
    • 식물병연구
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    • 제28권2호
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    • pp.57-60
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    • 2022
  • Leaves of Chionanthus retusus were found to be damaged by leaf spot disease associated with a fungus in Iksan, Korea. Leaf spots were angular to irregular, vein-limited, scattered, 1-8 mm diameter, brownish-gray to dark brown when dry, with heavy fructification. The pathogen causes premature defoliation of C. retusus plant and was identified as Pseudocercospora chionanthi-retusi based on morphological and molecular-phylogenetic analyses. The phylogenetic tree was constructed using multi-locus DNA sequence data of partial actin (actA), partial translation elongation factor 1-alfa (tef1), partial DNA-directed RNA polymerase II second largest subunit (rpb2) genes, and internal transcribed spacer regions. Current study provides detail morphological description of P. chionanthi-retusi on C. retusus in Korea, with supports of phylogenetic analysis and pathogenicity test.

Characterizing Hydraulic Properties by Grain-Size Analysis of Fluvial Deposits Depending on Stream Path in Korea

  • Oh, Yun-Yeong;Hamm, Se-Yeong;Chung, Sang Yong;Lee, Byeong Dae
    • Environmental Engineering Research
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    • 제18권3호
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    • pp.129-137
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    • 2013
  • The infiltration of rainwater into the surface soil is highly dependent on hydraulic variables, such as the infiltration rate, capillary fringe, moisture content, and unsaturated/saturated hydraulic conductivity. This study estimates the hydraulic conductivity (K) of fluvial deposits at three sites on the right and left banks of Nakdong River in Gyeongbuk Province, South Korea, including the Gumi, Waegwan, and Seongju bridge sites. The K values of 80 samples from 13 boreholes were estimated by using six grain-size methods (Hazen, Slichter, Kozeny, Beyer, Sauerbrei, and Pavchich formulae). The Beyer, Hazen, and Slichter methods showed a better relationship with K values along with an effective grain size than did the other three methods. The grain-size, pumping test, and slug test analyses resulted in different K values, but with similar K values in the grain-size analysis and pumping test. The lower K values of the slug test represent the uppermost fine sand layer.

병원간호사의 임금체계와 임금형태 분석;노동조합설립 병원을 중심으로 (An Analysis of Pay System and Pay Form of Hospital Nurses)

  • 박희옥
    • 간호행정학회지
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    • 제12권4호
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    • pp.521-531
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    • 2006
  • Purpose: The purpose of this study were to examine the pay system and pay form of hospital nurses. Methods: This study performed secondary analysis on the existing data and employed a case study design. Data were collected from May 1, 2005 to September 30, 2005. Analysis of the results was carried out using SPSS win 12.0 for frequency, percentage, mean and standard deviation. Results: All hospitals did have pay steps considering the seniority rule. Each hospital had a variety types of an allowances, the criteria of the payment, and the bonus. The majority of payment form was a monthly pay. Several suggestions could be drawn from this study. The pay system of the hospital nurses should reflect market pay and pay system should be set up according to the value of duty, performance, and expertness of hospital nurses and should be clear and lucid. Conclusion: Pay is a major function of human resource management and is a motive to nurses. Each hospital's pay system is different outwardly but it is the same as internally. Therefore pay system and form should reflect a value of the duty and the expertness and performance of nurses.

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압축하중시 RPI clasp의 3가지 다른 proximal plate 형태에 따른 지대치 주위조직의 광탄성 응력 분석 (Photoelastic Stress Analysis of the Abutment Surrounding Tissue According to Shape of the Proximal Plate of the RPI Clasp)

  • 최정수;김부섭
    • 대한치과기공학회지
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    • 제34권4호
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    • pp.473-482
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    • 2012
  • Purpose: The purpose of this study was to investigate the stress distribution of the surrounding tissues according to 3 proximal plate types of the RPI clasp. Methods: The removeable partial denture which mandibular right and left second premolars and mandibular molars were lost was attached to a three dimensional photo elastic epoxy resin model. Then 120N of vertical load was applied. After 3-dimensional photoelastic stress analysis was used to record the isochromatic fringe patterns. Results: Kratochvil type guiding plane exhibited little uniform stress distribution on load center and alveolar ridge, but higher stress concentration on buccal surface of second premolar. Krol type guiding plane exhibited the stress concentration on the front of load center and relatively higher stress concentration on buccal surface of first premolar. However, this type had no effect on canine. Researcher type guiding plane showed the stress concentration on second premolar and molar, but the little stress distribution on first premolar. Conclusion: In all types, excessive stress concentration was appeared and three types were not significant different.

Retrieving Phase from Single Interferogram with Spatial Carrier Frequency by Using Morlet Wavelet

  • Hongxin Zhang;Mengyuan Cui
    • Current Optics and Photonics
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    • 제7권5호
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    • pp.529-536
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    • 2023
  • The Morlet wavelet transform method is proposed to analyze a single interferogram with spatial carrier frequency that is captured by an optical interferometer. The method can retain low frequency components that contain the phase information of a measured optical surface, and remove high frequency disturbances by wavelet decomposition and reconstruction. The key to retrieving the phases from the low-frequency wavelet components is to extract wavelet ridges by calculating the maximum value of the wavelet transform amplitude. Afterwards, the wrapped phases can be accurately solved by multiple iterative calculations on wavelet ridges. Finally, we can reconstruct the wave-front of the measured optical element by applying two-dimensional discrete cosine transform to those wrapped phases. Morlet wavelet transform does not need to remove the spatial carrier frequency components manually in the processing of interferogram analysis, but the step is necessary in the Fourier transform algorithm. So, the Morlet wavelet simplifies the process of the analysis of interference fringe patterns compared to Fourier transform. Consequently, wavelet transform is more suitable for automated programming analysis of interference fringes and avoiding the introduction of additional errors compared with Fourier transform.

필지중심 토지이용변화패튼엔 관한 연구 (A Study on the patterns of land use change based on the digital parcels)

  • 김정훈
    • Spatial Information Research
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    • 제10권1호
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    • pp.153-164
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    • 2002
  • 이 연구는 수도권 주변지역을 대상으로 토지이용변화의 결정변수를 찾는 과정에서 인접하고 있는 필지들이 당해필지의 토지이용변화에 어느 정도 영향을 미치는가 하는 것을 분석하기 위해 수행되어졌다. 그리드 셀(Cell)과 달리 지적을 기본도로 해서 인접필지를 추출할 경우 불규칙적인 필지형상과 필지면적 그리고 당해 필지에 면하고 있는 길이 또한 다양하기 때문에 일반적인 원칙을 가지고 접근하기가 어렵다 연구수행중 인접필지를 어떻게 추출하느냐 하는 것이 큰 관건이었다. 그래서 이 논문은 별도로 인접필지를 추출하는 방법을 정리하고 과 결과를 활용하여 실제 사례지역의 토지이용변화패튼과 인접필지 토지이용분포패튼을 살펴보고자 한다. 이 연구는 우선 Avenue프로그램을 응용하여 수치지적도 폴리곤(이하 필지)이 기본적으로 가지고 있는 ID와 인접필지 ID를 찾아내었다. 그리고 인접필지 ID를 현재 이용되고 있는 토지용도로 바꾸었다 이것을 위해서 이 연구는 EXCEL의 Lookup기능을 사용했다. 인접필지의 토지용도를 얻은 후, 다음 단계는 당해필지에 영향을 푸는 인접필지 토지용도 감을 어떻게 정하느냐 하는 것이다 이것을 위해서 이 연구는 Visual Basic을 사용하였다. 인접하고 있는 필지들의 토지용도를 모두 다 합하고 각 해당용도마다 전체필지 중에 차지하는 비율을 구하였다. 최종적으로 이 연구는 당해필지에 인접하고 있는 총 인접필지 중에 도시적 용도 즉 대지, 공장, 공공시설로 이용되고 있는 비율감의 합을 인접필지의 토지이용과 관련된 종속변수 감으로 정하였다. 이 분석은 대도시 주변지역의 토지이용변화패튼을 이해하는데 활용될 수 있을 것이다. 또한 자방자치단체가 행정구역내에 일어나고 있는 토지이용변화현상을 이해하고 효율적으로 관리할 수 있는 방안을 마련하는 데도 활용될 수 있을 것이다.

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디젤 엔진에서 생성된 크랭크케이스 수트의 재활용 가능성 연구 (Study on the Possibility of Recycling Crankcase Soot from Diesel Engine)

  • 김수양;최재혁;노범석;김준수;강준;이원주
    • 해양환경안전학회지
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    • 제27권1호
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    • pp.179-186
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    • 2021
  • 본 연구에서는 선박용 디젤 엔진에서 발생되는 크랭크케이스 수트(soot)의 재활용 가능성을 검토하기 위하여, 수트를 배기관에서 발생하는 수트와 크랭크케이스에서 발생한 수트로 분류하고, 열처리에 따른 수트의 구조적 특성을 분석하였다. 열처리는 아르곤 가스 분위기에서 2,000℃와 2,700℃로 열처리를 수행하였고, 샘플의 구조적 특성 분석을 위해 라만분광법(Raman spectroscopy)과 고분해능 전자현미경(HRTEM)을 활용하였다. 또한, 취득한 HRTEM 이미지를 정량적으로 분석하기 위해 디지털 이미지 처리(Digital Image Processing) 기법을 활용하였다. 라만 분석 결과, 배기 수트와 2,700℃로 열처리한 수트에서 상대적으로 높은 G/D ratio가 나타났다. HRTEM 이미지에서는 두 수트 모두 유사한 형태의 흑연화된 나노 구조를 확인할 수 있었으나, 수트의 종류와 열처리 온도차에 따른 흑연화 정도의 차이를 정량적으로 도출할 수 없는 한계가 있었다. 이에 Digital Image Processing을 통해 HRTEM 이미지의 fringe의 길이와 곡률을 정량적으로 분석하였으며, 라만 분석과 일치하는 결과를 도출할 수 있었다. 이는 배기 수트가 크랭크케이스 수트에 비해 더 흑연화 된 구조를 가지는 것을 의미하며, 더 높은 온도에서 열처리 할 경우 흑연의 구조로 더 잘 발달함을 의미한다. 본 연구의 결과로 크랭크케이스 수트 역시 배기 수트와 마찬가지로 흑연계 재료로 재활용이 가능함을 확인하였다.