• Title/Summary/Keyword: Masking

Search Result 747, Processing Time 0.027 seconds

CHD4 Conceals Aberrant CTCF-Binding Sites at TAD Interiors by Regulating Chromatin Accessibility in Mouse Embryonic Stem Cells

  • Han, Sungwook;Lee, Hosuk;Lee, Andrew J.;Kim, Seung-Kyoon;Jung, Inkyung;Koh, Gou Young;Kim, Tae-Kyung;Lee, Daeyoup
    • Molecules and Cells
    • /
    • v.44 no.11
    • /
    • pp.805-829
    • /
    • 2021
  • CCCTC-binding factor (CTCF) critically contributes to 3D chromatin organization by determining topologically associated domain (TAD) borders. Although CTCF primarily binds at TAD borders, there also exist putative CTCF-binding sites within TADs, which are spread throughout the genome by retrotransposition. However, the detailed mechanism responsible for masking the putative CTCF-binding sites remains largely elusive. Here, we show that the ATP-dependent chromatin remodeler, chromodomain helicase DNA-binding 4 (CHD4), regulates chromatin accessibility to conceal aberrant CTCF-binding sites embedded in H3K9me3-enriched heterochromatic B2 short interspersed nuclear elements (SINEs) in mouse embryonic stem cells (mESCs). Upon CHD4 depletion, these aberrant CTCF-binding sites become accessible and aberrant CTCF recruitment occurs within TADs, resulting in disorganization of local TADs. RNA-binding intrinsically disordered domains (IDRs) of CHD4 are required to prevent this aberrant CTCF binding, and CHD4 is critical for the repression of B2 SINE transcripts. These results collectively reveal that a CHD4-mediated mechanism ensures appropriate CTCF binding and associated TAD organization in mESCs.

Improved SITM Attack on the PRESENT Blockcipher (블록암호 PRESENT에 대한 향상된 SITM 공격)

  • Park, Jonghyun;Kim, Hangi;Kim, Jongsung
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.32 no.2
    • /
    • pp.155-162
    • /
    • 2022
  • The SITM (See-In-The-Middle) attack proposed in CHES 2020 is a type of analysis technique that combines differential cryptanalysis and side-channel analysis, and can be applied even in a harsh environment with a low SNR (Signal-to-Noise Ratio). This attack targets partial 1st or higher order masked block cipher, and uses unmasked middle round weakness. PRESENT is a lightweight blockcipher proposed in CHES 2007, designed to be implemented efficiently in a low-power environment. In this paper, we propose SITM attacks on 14-round masked implementation of PRESENT while the previous attacks were applicable to 4-round masked implementation of PRESENT. This indicates that PRESENT has to be implemented with more than 16-round masking to be resistant to our attacks.

A Method for Region-Specific Anomaly Detection on Patch-wise Segmented PA Chest Radiograph (PA 흉부 X-선 영상 패치 분할에 의한 지역 특수성 이상 탐지 방법)

  • Hyun-bin Kim;Jun-Chul Chun
    • Journal of Internet Computing and Services
    • /
    • v.24 no.1
    • /
    • pp.49-59
    • /
    • 2023
  • Recently, attention to the pandemic situation represented by COVID-19 emerged problems caused by unexpected shortage of medical personnel. In this paper, we present a method for diagnosing the presence or absence of lesional sign on PA chest X-ray images as computer vision solution to support diagnosis tasks. Method for visual anomaly detection based on feature modeling can be also applied to X-ray images. With extracting feature vectors from PA chest X-ray images and divide to patch unit, region-specific abnormality can be detected. As preliminary experiment, we created simulation data set containing multiple objects and present results of the comparative experiments in this paper. We present method to improve both efficiency and performance of the process through hard masking of patch features to aligned images. By summing up regional specificity and global anomaly detection results, it shows improved performance by 0.069 AUROC compared to previous studies. By aggregating region-specific and global anomaly detection results, it shows improved performance by 0.069 AUROC compared to our last study.

Speed Prediction and Analysis of Nearby Road Causality Using Explainable Deep Graph Neural Network (설명 가능 그래프 심층 인공신경망 기반 속도 예측 및 인근 도로 영향력 분석 기법)

  • Kim, Yoo Jin;Yoon, Young
    • Journal of the Korea Convergence Society
    • /
    • v.13 no.1
    • /
    • pp.51-62
    • /
    • 2022
  • AI-based speed prediction studies have been conducted quite actively. However, while the importance of explainable AI is emerging, the study of interpreting and reasoning the AI-based speed predictions has not been carried out much. Therefore, in this paper, 'Explainable Deep Graph Neural Network (GNN)' is devised to analyze the speed prediction and assess the nearby road influence for reasoning the critical contributions to a given road situation. The model's output was explained by comparing the differences in output before and after masking the input values of the GNN model. Using TOPIS traffic speed data, we applied our GNN models for the major congested roads in Seoul. We verified our approach through a traffic flow simulation by adjusting the most influential nearby roads' speed and observing the congestion's relief on the road of interest accordingly. This is meaningful in that our approach can be applied to the transportation network and traffic flow can be improved by controlling specific nearby roads based on the inference results.

Semantic Occlusion Augmentation for Effective Human Pose Estimation (가려진 사람의 자세추정을 위한 의미론적 폐색현상 증강기법)

  • Hyun-Jae, Bae;Jin-Pyung, Kim;Jee-Hyong, Lee
    • KIPS Transactions on Software and Data Engineering
    • /
    • v.11 no.12
    • /
    • pp.517-524
    • /
    • 2022
  • Human pose estimation is a method of estimating a posture by extracting a human joint key point. When occlusion occurs, the joint key point extraction performance is lowered because the human joint is covered. The occlusion phenomenon is largely divided into three types of actions: self-contained, covered by other objects, and covered by background. In this paper, we propose an effective posture estimation method using a masking phenomenon enhancement technique. Although the posture estimation method has been continuously studied, research on the occlusion phenomenon of the posture estimation method is relatively insufficient. To solve this problem, the author proposes a data augmentation technique that intentionally masks human joints. The experimental results in this paper show that the intentional use of the blocking phenomenon enhancement technique is strong against the blocking phenomenon and the performance is increased.

Study for the Pseudonymization Technique of Medical Image Data (의료 이미지 데이터의 비식별화 방안에 관한 연구)

  • Baek, Jongil;Song, Kyoungtaek;Choi, Wonkyun;Yu, Khiguen;Lee, Pilwoo;In, Hanjin;Kim, Cheoljung;Yeo, Kwangsoo;Kim, Soonseok
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
    • /
    • v.6 no.6
    • /
    • pp.103-110
    • /
    • 2016
  • The recent frequent cases of damage due to leakage of medical data and the privacy of medical patients is increasing day by day. The government says the Privacy Rule regulations established for these victims, such as prevention. Medical data guidelines can be seen 'national medical privacy guidelines' is only released. When replacing the image data between the institutions it has been included in the image file (JPG, JPEG, TIFF) there is exchange of data in common formats such as being made when the file is leaked to an external file there is a risk that the exposure key identification information of the patient. This medial image file has no protection such as encryption, This this paper, introduces a masking technique using a mosaic technique encrypting the image file contains the application to optical character recognition techniques. We propose pseudonymization technique of personal information in the image data.

Semantic Pre-training Methodology for Improving Text Summarization Quality (텍스트 요약 품질 향상을 위한 의미적 사전학습 방법론)

  • Mingyu Jeon;Namgyu Kim
    • Smart Media Journal
    • /
    • v.12 no.5
    • /
    • pp.17-27
    • /
    • 2023
  • Recently, automatic text summarization, which automatically summarizes only meaningful information for users, is being studied steadily. Especially, research on text summarization using Transformer, an artificial neural network model, has been mainly conducted. Among various studies, the GSG method, which trains a model through sentence-by-sentence masking, has received the most attention. However, the traditional GSG has limitations in selecting a sentence to be masked based on the degree of overlap of tokens, not the meaning of a sentence. Therefore, in this study, in order to improve the quality of text summarization, we propose SbGSG (Semantic-based GSG) methodology that selects sentences to be masked by GSG considering the meaning of sentences. As a result of conducting an experiment using 370,000 news articles and 21,600 summaries and reports, it was confirmed that the proposed methodology, SbGSG, showed superior performance compared to the traditional GSG in terms of ROUGE and BERT Score.

A Selective and Sensitive Determination Method of Fe(II) ion using DTPA in Luminol-H2O2 System (Fe(II)-DTPA 착물의 촉매작용을 이용한 루미놀 화학발광 시스템의 선택적 Fe(II) 정량)

  • Lee, Sang Hak;Kim, Kyung Min;Hong, Suk Joo;Kim, Gyu-Man;Jo, Hae Jin;Jang, Taek Gyun;Kim, Young Ho
    • Applied Chemistry
    • /
    • v.15 no.2
    • /
    • pp.113-116
    • /
    • 2011
  • A sensitive and selective determination method of Fe(II) ion by luminol-H2O2 system using a chelating reagent has been presented. A metal ion-chelating ligand complex such as Fe(II)-diethylenetriamine pentaacetic acid (DTPA) produced higher chemiluminescence (CL) intensity as well as longer lifetime in luminol-H2O2 system than metal exist as free ions. Furthermore, the catalytic activity of Cu(II) and Pb (II) complexes with chelating reagents in luminol-H2O2 system was lost since chelating reagents act as a masking agent although free Cu(II) and Pb(II) ions have high catalytic activity. On the optimized conditions, the calibration curve of Fe(II) ion was linear over the range from 1.0×10-7 to 2.0×10-5 M with correlation coefficient of 0.996. The detection limit was calculated to be 4.0×10-8 M.

Quality Characteristics of Rice Paper Roll with Frozen Rainbow Trout Oncorhynchus mykiss Meat Treated with Polysaccharide and TGase (다당류 및 TGase를 처리한 동결 무지개송어(Oncorhynchus mykiss)를 활용한 라이스페이퍼롤의 품질 특성)

  • Hye Min Park;Jong Bong Lee;Byoung Kyu An;Woo Jin Lee;Jung-Jin In;Hyeong Gu Han;Seung Ah Son;Yeon Joo Bae;Kil Bo Shim
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.56 no.5
    • /
    • pp.585-595
    • /
    • 2023
  • This study was conducted to optimize the rice paper roll processing conditions with frozen rainbow trout Oncorhynchus mykiss meat (RPR-FRT) treated with polysaccharide and TGase using a response surface methodology and to examine their quality characteristics. The RSM results for the RPR-FRT showed that the optimum condition for the garlic-pepper mixture was 21.2 g and that for starch was 22.6 g based on 150 g of RPR-FRT. The RPR-FRT contained 58.47 g/100 g of moisture, 8.57 g/100 g of crude protein, 3.28 g/100 g of crude lipid, and 1.00 g/100 g of ash. The vitamin E content was 1,010.91 ㎍/100 g. Based on their contents, the samples could be considered good supplements for P, Cr, and Se. The RPR-FRT contained unsaturated fatty acids (75.84%), DHA (10.33%), and EPA (2.56%). Anserine, arginine, glycine, and taurine accounted for 41.93%, 11.27%, 7.13%, and 7.00% of free amino acids in the RPR-FRT, respectively. The sulfur compounds in the RPR-FRT constituted 73.16% of the total flavor compounds. The RPR-FRT prepared using the optimum conditions was superior in masking off-flavor and showed improved nutritional content.

Speech Reinforcement Based on Soft Decision Under Far-End Noise Environments (원단 잡음 환경에서 Soft Decision에 기반한 새로운 음성 강화 기법)

  • Choi, Jae-Hun;Chang, Joon-Hyuk
    • The Journal of the Acoustical Society of Korea
    • /
    • v.27 no.7
    • /
    • pp.379-385
    • /
    • 2008
  • In this paper, we propose an effective speech reinforcement technique under the near-end and the far-end noise environments. In general, since the intelligibility of the far-end speech for the near-end listener is significantly reduced under near-end noise environments, we require a far-end speech reinforcement approach to avoid this phenomena. Specifically, based on the estimated background noise spectrum of the near-end, we reinforce the far-end speech spectrum by incorporating the more general cases under the near-end with background noise. Also, we propose the novel approach to reinforce the actual speech signal except for the noise signal in the far-end noisy speech signal. The performance of the proposed algorithm is evaluated by the CCR (Comparison Category Rating) test of the method for subjective determination of transmission quality in ITU-T P.800 under various noise environments and shows better performances compared with the conventional method.