• Title/Summary/Keyword: Z-contrast technique

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Crystallographic Characterization of the (Bi, La)4Ti3O12 Film by High-Resolution Electron Microscopy (고분해능 전자현미경법을 이용한 (Bi, La)4Ti3O12 박막의 결정학적 특성 평가)

  • Lee, Doek-Won;Yang, Jun-Mo;Park, Tae-Su;Kim, Nam-Kyung;Yeom, Seung-Jin;Park, Ju-Chul;Lee, Soun-Young;Park, Sung-Wook
    • Korean Journal of Materials Research
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    • v.13 no.7
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    • pp.478-483
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    • 2003
  • The crystallographic characteristics of the $(Bi, La)_4$$Ti_3$$O_{12}$ thin film, which is considered as an applicable dielectrics in the ferroelectric RAM device due to a low crystallization temperature and a good fatigue property, were investigated at the atomic scale by high resolution transmission electron microscopy and the high resolution Z-contrast technique. The analysis showed that a (00c) preferred orientation and a crystallization of the film were enhanced with the diffraction intensity increase of the (006) and (008) plane as the annealing temperature increased. It indicated a change of the atomic arrangement in the (00c) plane. Stacking faults on the (00c) plane were also observed. Through the comparison of the high-resolution Z-contrast image and the $Bi_4$$Ti_3$$O_{12}$ atomic model, it was evaluated that the intensity of the Bi atom was different according to the atomic plane, and it was attributed to a substitution of La atom for Bi at the specific atom position.

A Study on NDE technique using Acoustic Reflection Microscope (반사형 음향 현미경을 이용한 비파괴 검사 기술에 관한 연구)

  • Moon, Geon;Ko, Dae-Sik;Kim, Jang-Gwon;Jun, Gye-Seok
    • The Journal of the Acoustical Society of Korea
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    • v.6 no.3
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    • pp.23-30
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    • 1987
  • In this paper, the characteristic response of reflected signals of acoustic reflection microscope, V(z) phenomenon, has been studied and a new type of NDE technique has been presented. 10 Won coin, aluminium, IC component, and kevlar-epoxy samples have been used for the experiment of NDE and the acoustic microscope operating at a center frequency of 3 MHz has been used in the focused or defocused mode of operation. In experiment, it has been shown that the acoustic microscope has the resolution of $500\mu m$ and the defects present on the surface and near surface of samples have been detected by acoustic transducer and imaged on a monitor, and the variation of the contrast of image for samples has been in good agreement with V(z) phenomenon.

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A Comparative Study of between Cultivar and Wild type of Angelica tenuissima in korea (한국산(韓國産) 재배고본(栽培藁本)과 야생고본(野生藁本)에 대한 비교(比較) 연구(硏究))

  • Han, Sin-Hee;Lee, Jung-Hoon;Kil, Gi-Jung
    • The Korea Journal of Herbology
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    • v.22 no.3
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    • pp.1-7
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    • 2007
  • Objectives : This research was observed by examining the external and internal parts and the quantity of the surface components of the wild type and cultivar of Angelica tenuissima in korea. Methods : The slice of the tested material made by paraffin section technique was colored with Safranine Malachite Green contrast methods, and then observed and photographed by the microscope and examined the quantity of the surface components. Results : 1. The cultivar has comparatively many thick roots while the wild type has many radicles, with its root and stem constituting the major part, and the size of its root is small. 2. In case of ferulic acid, the wild type contains 0.066% of it, while the cultivar, 0.031%, The wild type contains 4.258% of z-ligustilide and the cultivar, 1.956%. Conclusions : It was thought that there might be also some differences in their genetic characteristics, etc. On this, however, further in-depth study is needed.

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Broad Wings around Hα and Hβ in the S-type Symbiotic Stars

  • Chang, Seok-Jun;Lee, Hee-Won;Lee, Ho-Gyu
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.86.4-87
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    • 2017
  • Symbiotic stars are binary systems composed of a hot white dwarf and a mass losing giant. Many symbiotic stars are known to exhibit broad wings around Balmer emission line. We show high resolution spectra of S-type symbiotic stars, Z Andromedae and AG Draconis, obtained with the ESPaDOnS and the 3.6 m Canada-France-Hawaii Telescope, in which we find prominent broad wings around Balmer lines. We adopt Monte-Carlo technique to consider two types of wing formation mechanisms, which are Thomson scattering by free electron in H II region and Raman scattering by atomic hydrogen in H I region. We find that Thomson wings of $H{\alpha}$ and $H{\beta}$ have the same widths in the Doppler space due to the cross section independent of wavelength. In contrast, Raman $H{\alpha}$ wings are 3 times broader widths than $H{\beta}$ counterparts, which is attributed to the different cross sections and branching ratios. Our CFHT data show that $H{\alpha}$ wings of Z Andromedae and AG Draconis are broader than $H{\beta}$ wings, lending strong support to the Raman scattering origin of Balmer wings in these objects.

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Perfusion RRI of the Brain Using Oxygen Inhalation (산소 호흡을 이용한 뇌의 관류 자기공명영상)

  • 최순섭
    • Investigative Magnetic Resonance Imaging
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    • v.4 no.2
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    • pp.113-119
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    • 2000
  • Purpose : To know the possibility of clinical application of MRI using oxygen inhalation as a perfusion MRI Materials and methods : Two healthy volunteers and three patients of one moyamoya disease, one acute infarction and one meningioma were studied using a 1.5 Tesla MRI unit. Oxygen (15 liters/min) mixed with room air was given using face mask from 8 second to 35 second during the study. Images were acquired 25 times (scan time per study were 1.6 seconds) using susceptibility contrast EPI (echo planar image) sequence. Difference maps were acquired by early (study 12-18), and late (study 19-25) O2 inhalation image groups minus pre-O2 inhalation image group (study 3-9) with a Z-score of 0.7-1.0 using VB31C program of Magneton Vision. The resulting perfusion images were created by superimposition of difference maps on corresponding T1 weighted anatomic images. On moyamoya patient, similar perfusion images were acquired after Gd-DTPA injection, and compared with O2 inhalation perfusion images. Results ; The author can get the perfusion images of the brain by oxygen inhalation with susceptibility contrast EPI sequence at the volunteers, and the patient of moyomoya disease, acute infarction and meningioma. On moyamoya patient, perfusion images with O2 inhalation are similar with perfusion images by Gd-DTPA injection. Conclusion 1 This study has demonstrated that the susceptibility contrast EPI by oxygen inhalation can be used as the clinically useful perfusion MRI technique

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A study of Satellite Image-Based Stereoscopic Vision System (위성영상 관련 입체도시시스템 개발에 관한 연구)

  • 김감래;김훈정;김주용
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2004.04a
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    • pp.239-243
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    • 2004
  • It does not exist almost that Most satellite image has both high spectral and spatial resolution. In order to apply the satellite image for to be actual, we need numerical and analytical technique development to improve the resolution. Specially in the function of solid illustration, we represent the solid image through the image generation to solid screen. The main function includes magnification, reduction, screen center movement, Panning, territory magnification. The method to process the image includes histogram and contrast modulation. Afterwards, we will develop the function includes 3-dimension cursor to control the elevation position and calculate the ground coordination automatically. There is the layer control includes the representation and the edition of 3D vector, extraction the Z value by On the Ground and digital elevation.

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Monitoring Technique of Pumpkin Fruit Flies Using Terpinyl Acetate-Protein Diet Lure and Development of Its Spraying Formulation for The Fly Control (Terpinyl acetate-단백질먹이 유인제를 이용한 호박과실파리류 연중발생 모니터링 기술 및 살포용 방제 제형 개발)

  • Kim, Yonggyun;Ahn, Jeong Joon
    • Korean journal of applied entomology
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    • v.59 no.1
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    • pp.15-22
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    • 2020
  • Two tephritid fruit flies are infesting pumpkins in Korea. Both are classified into genus of Zeugodacus. The striped fruit fly, Z. scutellata, males are attracted to a lure called Cuelure (CL), which has been used to monitor the occurrence of this fruit fly in the crop field. In contrast, no effective male lure was not developed to monitor the pumpkin fruit fly, Z. depressa. Protein diet lure has been used to attract females of most fruit flies. The addition of terpinyl acetate (TA) was effective to increase the attractiveness of Z. depressa. This study aimed to monitor the occurrence of Z. depressa in pumpkin field with TA-protein diet lure. To validate the efficiency of TA-protein diet lure, Z. scutellata was monitored in a year of 2019 using CL and TA-protein diet lures, and the yearly monitoring data were compared. The occurrence patterns derived from both lures were similar except late season after October. The extended catches of TA-protein diet lure might be explained by the adult diapause induction of Z. scutellata at late September. Monitoring Z. depressa with TA-protein diet lure gave two peaks at mid July and August-September, in which more than 80% catches were females. Based on the attractiveness of TA-protein diet lure, its wettable powder with an addition of spinosad insecticide was formulated and sprayed to pumpkin crops. After 7 days post-spray, the control efficacy recorded more than 70%. However, the control efficacies decreased as the time progressed after the spray. These results demonstrated the application of TA-protein diet lure for monitoring occurrence of Z. depressa in pumpkin-cultivating field conditions. The wettable powder containing spinosad can be applied to develop a new control agent against two pumpkin fruit flies.

Application of Dual-Energy Spectral Computed Tomography to Thoracic Oncology Imaging

  • Cherry Kim;Wooil Kim;Sung-Joon Park;Young Hen Lee;Sung Ho Hwang;Hwan Seok Yong;Yu-Whan Oh;Eun-Young Kang;Ki Yeol Lee
    • Korean Journal of Radiology
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    • v.21 no.7
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    • pp.838-850
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    • 2020
  • Computed tomography (CT) is an important imaging modality in evaluating thoracic malignancies. The clinical utility of dual-energy spectral computed tomography (DESCT) has recently been realized. DESCT allows for virtual monoenergetic or monochromatic imaging, virtual non-contrast or unenhanced imaging, iodine concentration measurement, and effective atomic number (Zeff map). The application of information gained using this technique in the field of thoracic oncology is important, and therefore many studies have been conducted to explore the use of DESCT in the evaluation and management of thoracic malignancies. Here we summarize and review recent DESCT studies on clinical applications related to thoracic oncology.

Research on Local and Global Infrared Image Pre-Processing Methods for Deep Learning Based Guided Weapon Target Detection

  • Jae-Yong Baek;Dae-Hyeon Park;Hyuk-Jin Shin;Yong-Sang Yoo;Deok-Woong Kim;Du-Hwan Hur;SeungHwan Bae;Jun-Ho Cheon;Seung-Hwan Bae
    • Journal of the Korea Society of Computer and Information
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    • v.29 no.7
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    • pp.41-51
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    • 2024
  • In this paper, we explore the enhancement of target detection accuracy in the guided weapon using deep learning object detection on infrared (IR) images. Due to the characteristics of IR images being influenced by factors such as time and temperature, it's crucial to ensure a consistent representation of object features in various environments when training the model. A simple way to address this is by emphasizing the features of target objects and reducing noise within the infrared images through appropriate pre-processing techniques. However, in previous studies, there has not been sufficient discussion on pre-processing methods in learning deep learning models based on infrared images. In this paper, we aim to investigate the impact of image pre-processing techniques on infrared image-based training for object detection. To achieve this, we analyze the pre-processing results on infrared images that utilized global or local information from the video and the image. In addition, in order to confirm the impact of images converted by each pre-processing technique on object detector training, we learn the YOLOX target detector for images processed by various pre-processing methods and analyze them. In particular, the results of the experiments using the CLAHE (Contrast Limited Adaptive Histogram Equalization) shows the highest detection accuracy with a mean average precision (mAP) of 81.9%.