• Title/Summary/Keyword: 대조도 증강

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Quantitative Analysis of Spatial Resolution for the Influence of the Focus Size and Digital Image Post-Processing on the Computed Radiography (CR(Computed Radiography)에서 초점 크기와 디지털영상후처리에 따른 공간분해능의 정량적 분석)

  • Seoung, Youl-Hun
    • Journal of Digital Convergence
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    • v.12 no.11
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    • pp.407-414
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    • 2014
  • The aim of the present study was to carry out quantitative analysis of spatial resolution for the influence of the focus size and digital image post-processing on the Computed Radiography (CR). The modulation transfer functions of an edge measuring method (MTF) was used for the evaluation of the spatial resolution. The focus size of X-ray tube was used the small focus (0.6 mm) and the large focus (1.2 mm). We evaluated the 50% and 10% of MTF for the enhancement of edge and contrast by using multi-scale image contrast amplification (MUSICA) in digital image post-processing. As a results, the edge enhancement than the contrast enhancement were significantly higher the spatial resolution of MTF 50% in all focus. Also the spatial resolution of the obtained images in a large focus were improved by digital image processing. In conclusion, the results of this study should serve as a basic data for obtain the high resolution clinical images, such as skeletal and chest images on the CR.

Evaluation of the Cause of Internal Jugular Vein Obstruction on Head and Neck Contrast Enhanced 3D MR Angiography Using Contrast Enhanced Computed Tomography (조영증강 전산화단층촬영술을 이용한 두경부 조영증강 삼차원 자기공명혈관촬영술에서 내경정맥 폐쇄의 원인 평가)

  • Gweon, Hye-Mi;Chung, Tae-Sub;Suh, Sang-Hyun
    • Investigative Magnetic Resonance Imaging
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    • v.15 no.1
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    • pp.41-47
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    • 2011
  • Purpose : To evaluate the cause of internal jugular vein (IJV) obstruction on contrast enhanced 3D MR angiography (CE-MRA) using contrast enhanced computed tomography (CE-CT). Materials and Methods : A total number of 30 patients were enrolled, who underwent both head and neck CE-MRA and CE-CT from 2005 to 2008. We defined obstruction group which had IJV obstruction and control group which had no IJV obstruction on CE-MRA. The following parameters were measured from axial images of CE-CT: 1) diameter of IJV; 2) distance between the styloid process and ipsilateral lateral mass of the atlas; 3) maximum area of lateral mass of the atlas. Each parameter was compared between obstruction group and control group. Results : The diameter of IJV and distance between the styloid process and lateral mass of the atlas at IJV obstruction side in obstruction group were $1.6{\pm}1.0\;mm$ and $4.1{\pm}2.1\;mm$ respectively, which resulted in statistical significance (p<0.01). The maximum area of lateral mass of the atlas at IJV obstruction side in obstruction group was $103.4{\pm}25.3\;mm^2$ which is significantly larger than in control group (p<0.05). Conclusion : We found that the cause of IJV obstruction on CE-MRA could be narrow space between the styloid process and the lateral mass of the atlas, which was related with asymmetric larger area of lateral mass of atlas.

Two-Stage Contrastive Learning for Representation Learning of Korean Review Opinion (두 단계 대조 학습 기반 한국어 리뷰 의견 표현벡터 학습)

  • Jisu Seo;Seung-Hoon Na
    • Annual Conference on Human and Language Technology
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    • 2022.10a
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    • pp.262-267
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    • 2022
  • 이커머스 리뷰와 같은 특정 도메인의 경우, 텍스트 표현벡터 학습을 위한 양질의 오픈 학습 데이터를 구하기 어렵다. 또한 사람이 수동으로 검수하며 학습데이터를 만드는 경우, 많은 시간과 비용을 소모하게 된다. 따라서 본 논문에서는 수동으로 검수된 데이터없이 양질의 텍스트 표현벡터를 만들 수 있도록 두 단계의 대조 학습 시스템을 제안한다. 이 두 단계 대조 학습 시스템은 레이블링 된 학습데이터가 필요하지 않은 자기지도 학습 단계와 리뷰의 특성을 고려한 자동 레이블링 기반의 지도 학습 단계로 구성된다. 또한 노이즈에 강한 오류함수와 한국어에 유효한 데이터 증강 기법을 적용한다. 그 결과 스피어먼 상관 계수 기반의 성능 평가를 통해, 베이스 모델과 비교하여 성능을 14.03 향상하였다.

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Data Augmentation Strategy based on Token Cut-off for Using Triplet Loss in Unsupervised Contrastive Learning (비지도 대조 학습에서 삼중항 손실 함수 도입을 위한 토큰 컷오프 기반 데이터 증강 기법)

  • Myeongsoo Han;Yoo Hyun Jeong;Dong-Kyu Chae
    • Proceedings of the Korea Information Processing Society Conference
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    • 2023.05a
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    • pp.618-620
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    • 2023
  • 최근 자연어처리 분야에서 의미론적 유사성을 반영하기 위한 대조 학습 (contrastive learning) 관련 연구가 활발히 이뤄지고 있다. 이러한 대조 학습의 핵심은 의미론적으로 가까워져야 하는 쌍과 멀어져야 하는 쌍을 잘 구축하는 것이지만, 기존의 손실 함수는 문장의 상대적인 유사성을 풍부하게 반영하는데 한계가 있다. 이를 해결하기 위해, 이전 연구에서는 삼중 항 손실 함수 (triplet loss)를 도입하였으며, 본 논문에서는 이러한 삼중 항을 구성하기 위해 대조 학습에서의 효과적인 토큰 컷오프(cutoff) 데이터 증강 기법을 제안한다. BERT, RoBERTa 등 널리 활용되는 언어 모델을 이용한 실험을 통해 제안하는 방법의 우수한 성능을 보인다.

A Comparative study on the Effectiveness of Bloodstain Enhancing Reagents for the Development of Bloody Prints on the Cadaver Skin (혈흔 증강시약들의 시체피부 혈액지문에 대한 효과성 비교)

  • Mim, Dong-Ki;Kim, Da-Ye;Kim, Seung-Gap;Lee, Ga-Eul;Lee, Eun-Hye;Yu, Je-Seol
    • The Journal of the Korea Contents Association
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    • v.16 no.6
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    • pp.474-480
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    • 2016
  • Bloody fingerprints are important in many cases - especially in murder case. This study compared effectiveness of some reagents which had better quality of developing bloody fingerprints from human skin. Leuco crystal violet(LCV), hungarian red, amido black, coomassie blue, acid violet17, and crowle's double stain were used. Fingerprints were generated in the depletion series, and tissue method was used in applying all reagents. LCV showed the best result in this study.

The Effects of New Nonspecific Immunostimulators in Pig (면역기능 증강성 신물질에 대한 돼지에서의 면역 증강성 실험)

  • Jung Ji-Youn;Ahn Nam-Shik;Park Joon-Suk;Jo Eun-Hye;Hwang Jae-Woong;Park Jung-Ran;Kim Sun-Jung;Lee Yong-Geon;Jeong Yun-Hyeok;Chung Ji-Hye;Lee Seung-Ho;Park Young-Seok;Park Byung-Kwon
    • Journal of Food Hygiene and Safety
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    • v.21 no.2
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    • pp.113-117
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    • 2006
  • New nonspecific immunostimulators (Koko enterprise Co., Ltd., Korea) were evaluated for its effectiveness as a nonspecific immunostimulator in pigs. The effects of new nonspecific immunostimulators were determined by analysis of cytokines using ELISA and blood-chemistry. IFN-r which is one of the cell mediated immune cytokines significantly increased in DIR-vitamineral 0.2% group posttreatment 4 weeks and was significantly higher IMF 0.2%, DIR-vita 0.1% and DIR-vitamineral 0.2% groups than control group in 3 months. DIR-vitamineral 0.2% had a most strong effectiveness as a nonspecific immunostimulator in our treatment materials in pigs. IMF 0.2% and DIR-vita 0.1% were seen that there had effectiveness of a nonspecific immunostimulator in posttreatment 3 months. IgG IgM and Total Ig which were humoral immune globulins, were not significantly changed in posttreatment 4 weeks and 3 months. In conclusion, this study has demonstrated that new nonspecific immunostimulators had an immunostimulatory effect on pigs through cell mediated immune response.

Antitumor and Immuno-potentiating activity against Mouse Sarcoma 180 by Crude Polysaccharides from Fruiting Body of Lentinus giganteus (대향고(Lentinus giganteus)의 자실체에서 추출한 조다당류가 생쥐의 Sarcoma 180에 미치는 항암 및 면역 증강효과)

  • Lee, Geon-Woo;Kim, Hye-Young;Hur, Hyun;Lee, Tae-Soo;Lee, U-Youn
    • The Korean Journal of Mycology
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    • v.36 no.1
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    • pp.75-83
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    • 2008
  • Lentinus giganteus, one of edible and medicinal mushroom belongs to Pleurotaceae of Agaricales, has been known to contain some inhibitive substances on Sarcoma 180 and curative effect on high blood pressure. Neutral saline soluble (0.9% NaCl), hot water soluble and methanol soluble substances (hereinafter referred to Fr. NaCl, Fr. HW and Fr. MeOH, respectively) were extracted from fruiting body of the mushroom. In vitro cytotoxicity tests, crude polysaccharides were not cytotoxic against cancer cell lines such as Sarcoma 180 and HepG2 at the concentration of $10{\sim}2,000\;{\mu}g/ml$, but crude polysaccharides from Fr. NaCl was toxic to NIH3T3 at the concentration of $10{\sim}2,000\;{\mu}g/ml$. Intraperitoneal injection with crude polysaccharides showed life prolongation effect of $14.3{\sim}67.5%$ in mice previously inoculated with Sarcoma 180, respectively. Fr. NaCl exhibited the immuno-potentiating activity of B lymphocyte by increasing the alkaline phosphatase activity by $1.53{\sim}1.68$ folds compared with control at the concentration of $50{\sim}200\;{\mu}g/ml$, respectively. The numbers of peritoneal exudate cells and circulating leukocytes were increased by 7.7 and 1.6 folds by injecting Fr. NaCl and Fr. MeOH into the mice at the concentration of 50 mg/ml body weight, respectively.

TAGS: Text Augmentation with Generation and Selection (생성-선정을 통한 텍스트 증강 프레임워크)

  • Kim Kyung Min;Dong Hwan Kim;Seongung Jo;Heung-Seon Oh;Myeong-Ha Hwang
    • KIPS Transactions on Software and Data Engineering
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    • v.12 no.10
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    • pp.455-460
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    • 2023
  • Text augmentation is a methodology that creates new augmented texts by transforming or generating original texts for the purpose of improving the performance of NLP models. However existing text augmentation techniques have limitations such as lack of expressive diversity semantic distortion and limited number of augmented texts. Recently text augmentation using large language models and few-shot learning can overcome these limitations but there is also a risk of noise generation due to incorrect generation. In this paper, we propose a text augmentation method called TAGS that generates multiple candidate texts and selects the appropriate text as the augmented text. TAGS generates various expressions using few-shot learning while effectively selecting suitable data even with a small amount of original text by using contrastive learning and similarity comparison. We applied this method to task-oriented chatbot data and achieved more than sixty times quantitative improvement. We also analyzed the generated texts to confirm that they produced semantically and expressively diverse texts compared to the original texts. Moreover, we trained and evaluated a classification model using the augmented texts and showed that it improved the performance by more than 0.1915, confirming that it helps to improve the actual model performance.

Immuno-stimulating and Antitumor Effects on Mouse Sarcoma 180 by Crude Polysaccharides Extracted from Fruiting Body of Hericium erinaceus (노루궁뎅이(Hericium erinaceus) 자실체 추출 조다당류의 생쥐 Sarcoma 180에 대한 면역증강 및 항암 효과)

  • Choi, Yon-Il;Lee, Jae-Seong;Lee, U-Youn;Lee, Tae-Soo
    • Journal of Life Science
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    • v.20 no.4
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    • pp.623-631
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    • 2010
  • Hericium erinaceus, an edible and medicinal mushroom belonging to the Basidiomycota family, has been used for curing gastric ulcers and stomach cancers in human beings and is also known to have good inhibitory effects on sarcoma 180 and Ehrlich carcinoma in mice. Neutral saline soluble (0.9% NaCl), hot water soluble and methanol soluble substances (hereinafter referred to as Fr. NaCl, Fr. HW and Fr. MeOH, respectively) were extracted from the fruiting body of the mushroom. In in vitro cytotoxicity tests, crude polysaccharides were not cytotoxic against cell lines such as Sarcoma 180, HepG2, HT-29 and NIH3T3 at concentrations of $10{\sim}2,000\;{\mu}g/ml$. Intraperitoneal injection with crude polysaccharides exhibited a life prolongation effect of 29.1~54.1% in mice previously inoculated with Sarcoma 180. Fr. Na increased the numbers of spleen cells by 2.9 fold at a concentration of $50\;{\mu}g/ml$ compared with the control. Fr. Na improved the immuno-potentiating activity of B lymphocytes by increasing alkaline phosphatase activity by 5.5 fold compared with the control at a concentration of $200\;{\mu}g/ml$. Fr. NaCl increased the numbers of peritoneal exudate cells and circulating leukocytes by 4 and 2.3 folds at a concentration of 50 mg/kg, respectively. Therefore, the crude polysaccharides extracted from the fruiting body of H. erinaceus could improve antitumor activities in mice.

Immuno-potentiating and Antitumor Effects against Mouse Sarcoma 180 by Crude Polysaccharides Extracted from Fruiting Body of Russula rosacea (장미무당버섯(Russula rosacea)의 자실체에서 추출한 조다당류의 생쥐 Sarcoma 180에 대한 면역증강 및 항암 효과)

  • Choi, Yon-Il;Lee, Geon-Woo;Hur, Hyun;Lee, U-Youn;Lee, Tae-Soo
    • The Korean Journal of Mycology
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    • v.36 no.1
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    • pp.84-92
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    • 2008
  • Russula rosacea, one of edible and medicinal mushroom belonging Agaricales of Basidiomycota, has been known to have good inhibitory effects on sarcoma 180 and Ehrlich carcinoma of mice. Neutral saline soluble (0.9% NaCl), hot water soluble and methanol soluble substances (hereinafter referred to Fr. NaCl, Fr. HW and Fr. MeOH, respectively) were extracted from fruiting body of the mushroom. In vitro cytotoxicity tests, crude polysaccharides were not cytotoxic against cancer cell lines such as Sarcoma 180, HepG2, HT-29 and NIH3T3 at the concentration of $10{\sim}2000\;{\mu}g/ml$. Intraperitoneal injection with crude polysaccharides exhibited life prolongation effect of $21.4{\sim}45%$ in mice previously inoculated with Sarcoma 180. Fr. HW improved the immuno-potentiation activity of B lymphocyte by increasing the alkaline phosphatase activity by 6.8 fold compared with control at the concentration of $500\;{\mu}g/ml$. In case of Fr. NaCl, the numbers of peritoneal exudate cells and circulating leukocytes were increased by 6 and 2.6 folds at the concentration of 50 mg/kg, respectively. Therefore, the antitumor effect against mice Sarcoma 180 by Russula rosacea could be due to immunomodulating activity.