• Title/Summary/Keyword: Fringe analysis

Search Result 239, Processing Time 0.023 seconds

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

  • 이해중;황운봉;박현철
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.16 no.5
    • /
    • pp.864-872
    • /
    • 1992
  • Two double-exposure holograms are made in the different view angle at the same time, using laser, by overlapping before and after the static deformation. These images are transfered to the computer. The fringe patterns of holograms are recognized by image processing and each component of the displacement and strain at each point of the specimen is obtained by vector analysis, and the results were presented in the graphical form. For the verification of all the ment process, the two experimental cases, the in-plane displacement by tension load and the out-of-plane displacement by bending load, are measured. These results are compared with the exact solution.

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

  • Li, Yongchun;Zheng, Sheng;Huang, Yao;Liu, Dejian
    • Journal of The Korean Astronomical Society
    • /
    • v.52 no.2
    • /
    • pp.49-55
    • /
    • 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
    • /
    • v.43 no.1
    • /
    • pp.6-15
    • /
    • 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
    • Research in Plant Disease
    • /
    • v.28 no.2
    • /
    • pp.57-60
    • /
    • 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
    • /
    • v.18 no.3
    • /
    • pp.129-137
    • /
    • 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.

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

  • Park, Hee-Ok
    • Journal of Korean Academy of Nursing Administration
    • /
    • v.12 no.4
    • /
    • pp.521-531
    • /
    • 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.

  • PDF

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

  • Choi, Jung Soo;Kim, Busob
    • Journal of Technologic Dentistry
    • /
    • v.34 no.4
    • /
    • pp.473-482
    • /
    • 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
    • /
    • v.7 no.5
    • /
    • pp.529-536
    • /
    • 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.

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

  • 김정훈
    • Spatial Information Research
    • /
    • v.10 no.1
    • /
    • pp.153-164
    • /
    • 2002
  • This used a new method to capture the neighbouring relationship among parcels. To define the neighbouring relationship, all the surrounding parcels in the study area can be identified as neighbours of the current parcel as long as they touch each other even at a point. To examine neighbouring parcels on all polygons of the study area, this study used ArcViews avenue programming which visited each polygon in turn and produced an outfile containing the parcel record ID and the contents of each of the adjacent parcels. The second thing is to translate the record IDs of neighbouring parcels into land use. For this, this study used the Lookup function in Excel to obtain neighbouring land use. To deal with how to calculate the ratio of each land use to neighbouring land uses, this study used Visual Basic. finally, this study considered a term of neighbour land use as the ratio of the number of urban use adjacent parcels to the total number of adjacent parcels. This study shows that GIS and spatial analysis can be applied to land use change in the urban fringe area at a very detailed level using municipal parcel data which occupies about 80% of administrative affairs, especially at the local government level in Korea. The results of analysis can be useful for local government to understand its situation and to manage land use efficiently in the urban fringe. The methodology developed in this study is especially useful for an empirical approach.

  • PDF

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

  • Kim, Soo-yang;Choi, Jae-Hyuk;Rho, Bum-Seok;Kim, Junsoo;Kang, Jun;Lee, Won-Ju
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.27 no.1
    • /
    • pp.179-186
    • /
    • 2021
  • In this study, we attempted to comparatively analyze the structural characteristics of soot generated from marine engines to review the possibility of recycling crankcase soot by classifying it as exhaust soot and crankcase soot. The annealing procedure was performed in an argon gas atmosphere at 2,000℃ and 2,700℃, and Raman spectroscopy and High-Resolution Transmission Electron Microscopy(HRTEM) were used to analyze the structural properties of the samples. Furthermore, digital image processing techniques were utilized to quantitatively analyze the acquired HRTEM images. The Raman analysis demonstrated a relatively high G/D ratio in the exhaust soot and annealing conditions at 2,700℃. In the HRTEM images, both soot were able to identify similar forms of graphite nanostructures, but there were limitations in that they could not quantitatively derive differences in the degree of graphite depending on the type of soot and annealing temperature. Thus, digital image processing quantitatively analyzed the length and tortuosity of the fringe of the HRTEM image, which is consistent with the Raman analysis. This meant that the exhaust soot had a more graphite structure than the crankcase soot, and that annealing at a higher temperature improved the graphite structure. This study confirmed that both the crankcase soot and exhaust soot can be recycled as a graphite materials.