• Title/Summary/Keyword: Contrast correction

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Study on Defects in 2D Materials using Atomic Resolution TEM

  • Ryu, Gyeong-Hui;Park, Hyo-Ju;Kim, Jeong-Hwa;Kim, Na-Yeon;Lee, Jong-Yeong;Lee, Jong-Hun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.87.1-87.1
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    • 2016
  • The unique properties of 2D materials significantly rely on the atomic structure and defects. Thus study at atomic scale is crucial for in-depth understanding of 2D materials and provides insights into its future applications. Using aberration-corrected transmission electron microscopes, atomic resolution imaging of individual atoms has been achieved even at a low kV. Ongoing optimization of aberration correction improves the spatial resolution better than angstrom and moreover boosts the contrast of light atoms. I present the recent progress of the study on the atomic structure and defects of monolayer and multilayer graphene, hBN and MoS2. Furthermore, the defect formation mechanisms of graphene, hexagonal boron nitride and MoS2 are discussed.

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Binding energy of H2 to MOF-5: A Model Study

  • Lee, Jae-Shin
    • Bulletin of the Korean Chemical Society
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    • v.32 no.12
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    • pp.4199-4204
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    • 2011
  • Using models simulating the environment of two distinct adsorption sites of $H_2$ in metal-organic framework-5 (MOF-5), binding energies of $H_2$ to MOF-5 were evaluated at the MP2 and CCSD(T) level. For organic linker section modeled as dilithium 1,4-benzenedicarboxylate ($C_6H_4(COO)_2Li_2$), the MP2 and CCSD(T) basis set limit binding energies are estimated to be 5.1 and 4.4 kJ/mol, respectively. For metal oxide cluster section modeled as $Zn_4O(CO_2H)_6$, while the MP2 basis set limit binding energy estimate amounts to 5.4 kJ/mol, CCSD(T) correction to the MP2 results is shown to be insignificant with basis sets of small size. Substitution of benzene ring with pyrazine ring in the model for the organic linker section in MOF-5 is shown to decrease the $H_2$ binding energy noticeably at both the MP2 and CCSD(T) level, in contrast to the previous study based on DFT calculation results which manifested substantial increase of $H_2$ binding energies upon substitution of benzene ring with pyrazine ring in the similar model.

Retrospective Study of 143 Dogs with Alimentary Foreign Bodies (개에서 발생한 소화기계 이물에 대한 회고분석 - 143 증례)

  • Choi, Jihye;Keh, Seoyeon;Kim, Hyunwook
    • Journal of Veterinary Clinics
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    • v.32 no.1
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    • pp.49-55
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    • 2015
  • This study was retrospectively investigated the clinical features, diagnostic imaging, treatment, and prognosis of foreign bodies according to alimentary site and type of foreign body, in 143 dogs. Among 28 breeds, Maltese, Shih Tzu, and terriers including the Yorkshire terrier were presented with high prevalence. Bone was the most commonly identified (33%) foreign body regardless of alimentary site. Approximately 76% of foreign bodies were in the stomach and small intestine. All esophageal foreign bodies were diagnosed on survey radiography, with the most common location being the caudal thoracic esophageal segment. Further diagnostic examinations including ultrasonography or contrast studies were additionally performed to detect radiolucent foreign bodies and perforation or leakage in the stomach and intestine. However, most seeds could be identified based on the characteristic features such as hyperdense thin double lines and inner gas on survey radiography. In conclusion, complications such as peritonitis and intestinal perforation were mainly observed in cases with seeds and linear foreign bodies. Especially, fabric foreign bodies could be induce peritonitis and re-perforation with high prevalence after surgical correction.

The Design of Intramedia Synchronization based QoS (QoS 기반의 미디어내 동기화 설계)

  • Park, Hong-Jin;Lee, Jun-Yeon;Kim, Chang-Min
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.8
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    • pp.2042-2049
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    • 1999
  • In contrast to traditional data communication, the multimedia communication must support variable requirements to multimedia application service. Specially, it is a critical issue that the synchronization supports a continuous and temporal relationship media playout in a distributed environment. But the continuously generated media in source can't guarantee the constant interval on playout for the destination due to the inconsistent network transmission delay and transmission error. In this paper, we introduce a intramedia synchronization mechanism for the continuous and synchronous playout of multimedia stream such as audio and video across a communication network. The proposed mechanism is based on the user defined QoS(Quality of Service) and the playout correction algorithm to guarantee the continuous media playout at the receiver.

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Surgical Treatment of Sliding Hiatal Hernia by Incisional Gastropexy at Fundus and Pylorus in a Chihuahua Dog (치와와견에서 위저부 및 유문부의 절개성 위고정술을 통한 축성열공허니아의 수술적 치료)

  • Jang Ha-young;Yoon Hun-young;Kim Jun-young;Han Hyun-jung;Jeong Soon-wuk
    • Journal of Veterinary Clinics
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    • v.22 no.1
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    • pp.76-78
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    • 2005
  • A 1 year 2 months old, male Chihuahua dog weighing 0.92 kg was presented with a history of intermittent vomiting after eating since two weeks ago. Based on the history, clinical signs, physical examination, and contrast radiographs, the diagnosis of sliding hiatal hernia was made. Diaphragmatic plication, esophagopexy and left-sided gastropexy concurrently required for surgical correction but in this case, diaphragmatic plication and esophagopexy could not be applied because of the patient's special condition. Instead, left-sided gastropexy was performed with additional pyloropexy. To treat reflux esophagitis, cimetidine and sucralfate were administrated and patient was fed in an upright position. Two days after the surgery, the patient showed normal activity and after then there was not found recurrence or complication.

A Study on the Consumer's Dissatisfaction for the Clothing Product -with YWCA Consumer's claims- (시판 의류제품에 관련된 소비자 불만에 관한 연구 -YMCA 소비자 고발자료를 중심으로-)

  • Choi, Hae Woon;Cha, Ok Seon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.17 no.4
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    • pp.550-564
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    • 1993
  • The purpose of this study is to investigate the consumer's claims related to clothing merchandise. By th origination stage of claims, details of claims, and treatments of claims purchasing places of clothing merchandise, the consumer's claims are analyzed which were lodged to in consumer's complaint center, Seoul YWCA, in 1981-1990. To analyze these data statistically, frequency and percentile are used. The results of analysis for consumer's claims are as next : 1. Concerning the sex distinction, female complainers are more than male complainers. About the age bracket, twenties and thirties are the most numerous. The originations of claims being various. It is laundry and dry cleaning stage out of them that rank first, and total numbers of claims for clothing products continually have increased during 1981-1990. Out of the clothing items, outerwears are of the first rank and formal wear and coat are highest in rank of outerwears. For claims about purchasing places, agency ranked first and market, department store, custome-made and discount store came after in order. 2. Concerning the contents, quality of clothing product ranks first, inferior service, price, contrast, unfair transaction ranks in order. There are claims about quality of clothing product that color change ranks first and damage and form change rank in order. 3. The treatments of claims are that counsel, exchange, refund, repair and correction rank in order.

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Recognition of Passport MRZ Information Using Combined Neural Networks (결합 신경망을 이용한 여권 MRZ 정보 인식)

  • Kim, Jinho
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.15 no.4
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    • pp.149-157
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    • 2019
  • In case of reading passport using a smart phone in contrast with a dedicated passport reading system, MRZ(Machine Readable Zone) character recognition can be hard when the character strokes were broken, touched or blurred according to the lighting condition, and the position and size of MRZ character lines were varied due to the camera distance and angle. In this paper, the effective recognition algorithm of the passport MRZ information using a combined neural network recognizer of CNN(Convolutional Neural Network) and ANN( Artificial Neural Network), is proposed under the various sized and skewed passport images. The MRZ line detection using connected component analysis algorithm and the skew correction using perspective transform algorithm are also designed in order to achieve effective character segmentation results. Each of the MRZ field recognition results is verified by using five check digits for deciding whether retrying the recognition process of passport MRZ information or not. After we implement the proposed recognition algorithm of passport MRZ information, the excellent recognition performance of the passport MRZ information was obtained in the experimental results for PC off-line mode and smart phone on-line mode.

Efficient Method of Detecting Blurry Images

  • Tsomko, Elena;Kim, Hyoung-Joong;Paik, Joon-Ki;Yeo, In-Kwon
    • Journal of Ubiquitous Convergence Technology
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    • v.2 no.1
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    • pp.27-39
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    • 2008
  • In this paper we present a simple, efficient method for detecting the blurry photographs. Recently many digital cameras are equipped with various auto-focusing functions to help users take well-focused pictures as easily as possible. In addition, motion compensation devices are able to compensate motion causing blurriness in the images. However, digital pictures can be degraded by limited contrast, inappropriate exposure, imperfection of auto-focusing or motion compensating devices, unskillfulness of the photographers, and so on. In order to decide whether to process the images or not, or whether to delete them or not, reliable measure of image degradation to detect blurry images from sharp ones is needed. This paper presents a blurriness/sharpness measure, and demonstrates its feasibility by using extensive experiments. This method is fast, easy to implement and accurate. Regardless of the detection accuracy, the proposed measure in this paper is not demanding in computation time. Needless to say, this measure can be used for various imaging applications including auto-focusing and astigmatism correction.

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Tonal Implementation of English Topic and Focus (영어 화제와 초점의 억양 실현 양상)

  • Kang, Sun-Mi;Ok, Eu-Rom;Kim, Kee-Ho
    • Speech Sciences
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    • v.10 no.4
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    • pp.41-55
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    • 2003
  • This paper investigates the tonal patterns of English information structure composed of topic and focus. It has been argued in previous theories that there is a significant relationship between English topic-focus structure and intonation. The English topic is marked with L+H* pitch accent and focus is marked with H* pitch accent. These theories, however, are oversimplified ones since they do not consider the contextual differences of topic and focus. To examine more concrete tonal patterns of English topic and focus, we classified topic into two subcategories of reminding topic and old-information topic. Focus was categorized into three: information focus, contrastive focus, and reference focus. The overall results show that native English speakers are inclined to use both the L+H* and H* pitch accent for the topic and focus of an utterance. We also observe a tendency to deaccentuate the topics given as old information and to mark the topics given as noun phrase with H* pitch accent. As for the intonation of focus, H* pitch accent is the most frequent type of accent, but L+H* also shows a high percentage of implementation especially in the context of correction or contrast.

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A Study on Urban Change Detection Using D-DSM from Stereo Satellite Data

  • Jang, Yeong Jae;Oh, Kwan Young;Lee, Kwang Jae;Oh, Jae Hong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.5
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    • pp.389-395
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    • 2019
  • Unlike aerial images covering small region, satellite data show high potential to detect urban scale geospatial changes. The change detection using satellite images can be carried out using single image or stereo images. The single image approach is based on radiometric differences between two images of different times. It has limitations to detect building level changes when the significant occlusion and relief displacement appear in the images. In contrast, stereo satellite data can be used to generate DSM (Digital Surface Model) that contain information of relief-corrected objects. Therefore, they have high potential for the object change detection. Therefore, we carried out a study for the change detection over an urban area using stereo satellite data of two different times. First, the RPC correction was performed for two DSMs generation via stereo image matching. Then, D-DSM (Differential DSM) was generated by differentiating two DSMs. The D-DSM was used for the topographic change detection and the performance was checked by applying different height thresholds to D-DSM.