• Title/Summary/Keyword: NLM

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A Trend Study on Collection Development Policy for Science and Technology Information Resources (과학기술정보 장서개발정책에 관한 동향연구)

  • Lee, Seon-Hee;Choi, Hee-Yoon
    • The Journal of the Korea Contents Association
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    • v.9 no.5
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    • pp.337-345
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    • 2009
  • World leading national science technology information institutes provide scientists with R&D information for increasing national competitiveness. Collection development policy is the guidelines for the science technology information institutes that identify information resources and connect them together to build an information network for supporting R&D. In order to draw main elements of the collection development policy for national level science and technology information institutes, this paper analyzed the policies of National Library of Medicine (NLM), British Library (BL), Canada Institute for Scientific and Technological Information (CISTI), and Korea Institute of Science and Technology Information(KISTI). The results of this study can be used as the guidelines for the science and technology information institutes for establishing collection development policy.

An approximated implementation of affine projection algorithm using Gram-Scheme orthogonalization (Gram-Schmidt 직교화를 이용한 affine projection 알고리즘의 근사적 구현)

  • 김은숙;정양원;박선준;박영철;윤대희
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.9B
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    • pp.1785-1794
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    • 1999
  • The affine projection algorithm has known t require less computational complexity than RLS but have much faster convergence than NLMS for speech-like input signals. But the affine projection algorithm is still much more computationally demanding than the LMS algorithm because it requires the matrix inversion. In this paper, we show that the affine projection algorithm can be realized with the Gram-Schmidt orthogonalizaion of input vectors. Using the derived relation, we propose an approximate but much more efficient implementation of the affine projection algorithm. Simulation results show that the proposed algorithm has the convergence speed that is comparable to the affine projection algorithm with only a slight extra calculation complexity beyond that of NLMS.

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Scheme for Reducing Harmonics in Output Voltage of Modular Multilevel Converters with Offset Voltage Injection

  • Anupom, Devnath;Shin, Dong-Cheol;Lee, Dong-Myung
    • Journal of Power Electronics
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    • v.19 no.6
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    • pp.1496-1504
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    • 2019
  • This paper proposes a new THD reduction algorithm for modular multilevel converters (MMCs) with offset voltage injection operated in nearest level modulation (NLM). High voltage direct current (HVDC) is actively introduced to the grid connection of offshore wind powers, and this paper deals with a voltage generation technique with an MMC for wind power generation. In the proposed method, third harmonic voltage is added for reducing the THD. The third harmonic voltage is adjusted so that each of the pole voltage magnitudes maintains a constant value with a maximum number of (N+1) levels, where N is the number of sub-modules per arm. By using the proposed method, the THD of the output voltage is mitigated without increasing the switching frequency. In addition, the proposed method has advantageous characteristics such as simple implementation. As a part of this study, this paper compares the THD results of the conventional method and the proposed method with offset voltage injection to reduce the THD. In this paper, simulations have been carried out to verify the effectiveness of the proposed scheme, and the proposed method is implemented by a HILS (Hardware in the Loop Simulation) system. The obtained results show agreement with the simulation results. It is confirmed that the new scheme achieved the maximum level output voltage and improved the THD quality.

A Comparison of the Rudin-Osher-Fatemi Total Variation model and the Nonlocal Means Algorithm

  • Adiya, Enkhbolor;Choi, Heung-Kook
    • Proceedings of the Korea Multimedia Society Conference
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    • 2012.05a
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    • pp.6-9
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    • 2012
  • In this study, we compare two image denoising methods which are the Rudin-Osher-Fatemi total variation (TV) model and the nonlocal means (NLM) algorithm on medical images. To evaluate those methods, we used two well known measuring metrics. The methods are tested with a CT image, one X-Ray image, and three MRI images. Experimental result shows that the NML algorithm can give better results than the ROF TV model, but computational complexity is high.

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Noise Reduction of the Distribution Line Communication System using NLMS Adaptive Filters (NLMS 적응필터를 이용한 배전선 반송통신 시스템의 잡은 저감)

  • 정원용;최태원;김석순;이수흠;고희석
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.8 no.6
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    • pp.63-70
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    • 1994
  • 컴퓨터나 정밀기기기의 빈번한 운용으로 배전선 반송통신 시스템의 신뢰도는 그 어느 때보다 크게 요구된다. 배전선에 나타나는 여러 종류의 잡음은 반송통신 정보를 쉽게 오염시켜 전체 시스템에 큰 영향을 미치게 된다. 본 논문에서는 평활 잡음과 60[Hz] 전원 주파수에 동기된 고조파 잡음제거를 위해 LMS와 NLMS알고리즘을 이용한 적응필터를 사용하였고 컴퓨터 시뮬레이션을 수행해 본 결과 신호 대 잡음비의 관점에서 LMS보다 NLMS의 탁월한 효과를 확인하였다.

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Resources for assigning MeSH IDs to Japanese medical terms

  • Tateisi, Yuka
    • Genomics & Informatics
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    • v.17 no.2
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    • pp.16.1-16.4
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    • 2019
  • Medical Subject Headings (MeSH), a medical thesaurus created by the National Library of Medicine (NLM), is a useful resource for natural language processing (NLP). In this article, the current status of the Japanese version of Medical Subject Headings (MeSH) is reviewed. Online investigation found that Japanese-English dictionaries, which assign MeSH information to applicable terms, but use them for NLP, were found to be difficult to access, due to license restrictions. Here, we investigate an open-source Japanese-English glossary as an alternative method for assigning MeSH IDs to Japanese terms, to obtain preliminary data for NLP proof-of-concept.

Expression of VEGF-C/VEGFR-3 in Human Laryngeal Squamous Cell Carcinomas and its Significance for Lymphatic Metastasis

  • Wang, Zhongliang;Chen, Yao;Li, Xiaofeng;Xu, Li;Ma, Wei;Chang, Lingmei;Ju, Funian
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.1
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    • pp.27-31
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    • 2012
  • Objectives: Expression of vascular endothelial growth factor C (VEGF-C)and vascular endothelial growth factor feceptor-3 (VEGFR-3) in laryngeal squamous carcinoma and its relationship to lymph node metastasis were investigated. Methods: VEGF-C and VEGFR-3 gene expression in 30 cases of normal laryngeal mucosa tissue (NLM), primary laryngeal carcinoma cell carcinomas (PLC) and cervical lymph nodes (CLN) was examined by reverse transcription polymerase chain reaction (RT-PCR). Protein levels of VEGF-C expression were determined by immunohistochemical staining in 60 cases of PLC. Results: Expression of VEGF-C and VEGFR-3 different among NLM, PLC and CLN in the same patient. In PLC, expression was significantly higher in lymph node positive group than in the lymph node negative group and associated with histological grade of differentiation; Expression of VEGF-C and VEGFR-3 was not linked with age, sex, site or T stage. Conclusions: A close correlation was found between VEGF-C/VEGFR-3 expression and lymph node metastasis in PLC, suggesting a role in metastasis of laryngeal carcinomas.

Rain Detection and Removal Algorithm using Motion-Compensated Non-local Means Filter for Video Sequences (동영상을 위한 움직임 보상 기반 Non-Local Means 필터를 이용한 우적 검출 및 제거 알고리즘)

  • Seo, Seung Ji;Song, Byung Cheol
    • Journal of Broadcast Engineering
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    • v.20 no.1
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    • pp.153-163
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    • 2015
  • This paper proposes a rain detection and removal algorithm that is robust against camera motion in video sequences. In detection part, the proposed algorithm initially detects possible rain streaks by using intensity properties and spatial properties. Then, the rain streak candidates are selected based on Gaussian distribution model. In removal part, a non-rain block matching algorithm is performed between adjacent frames to find similar blocks to the block that has rain pixels. If the similar blocks to the block are obtained, the rain region of the block is reconstructed by non-local means (NLM) filter using the similar neighbors. Experimental results show that the proposed algorithm outperforms the previous works in terms of subjective visual quality of de-rained video sequences.

Serum Carbohydrate Antigen 19-9 as an Indicator of Liver Metastasis in Colorectal Carcinoma Cases

  • Dong, Hang;Tang, Jie;Li, Long-Hao;Ge, Jun;Chen, Xin;Ding, Jing;Men, Hai-Tao;Luo, Wu-Xia;Du, Yang;Li, Cong;Zhao, Feng;Chen, Ye;Cheng, Ke;Liu, Ji-Yan
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.2
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    • pp.909-913
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    • 2013
  • Purpose: The liver is the organ to which colorectal carcinomas (CRCs) most commonly metastasize, and surgical resection has been established as the most effective and potentially curative treatment for CRC with liver metastasis (LM). Therefore, surveillance of LM is vital for improvement of prognosis of CRC patients. In this study, we aimed to explore the potential value of carbohydrate antigen 19-9 (CA 19-9), carcinoembryonic antigen (CEA), and marker enzymes in indicating LM with CRC. Methods: Three groups of eligible patients with metastatic cancers were retrospectively included: CRC patients with LM (CRC-LM) or without LM (CRC-NLM), and non-CRC patients with LM (NCRC-LM). All metastatic lesions were identified by CT or MRI. Data on characteristics of the patients, the primary site, the locations of metastasis, CA 19-9, CEA, and biochemical parameters were collected for analysis. Results: A total of 493 patients were retrospectively included. More alcohol consumption was found in CRC-LM than CRC-NLM. Some biochemical enzymes were found to be significantly higher in groups with LM than without (CRC-LM or NCRC-LM v.s CRC-NLM). Both CEA and CA 19-9 were much higher in CRC-LM than CRC-NLM or NCRC-LM. For CRC patients, CA 19-9, ${\gamma}$-glutamyl transpeptidase, CEA and alcohol consumption were identified as independent factors associated with LM. Conclusion: Our analysis suggested the CA 19-9 might be a potential valuable indicator for LM of CRC in the clinic.