• 제목/요약/키워드: Co-occurrence Analysis

검색결과 463건 처리시간 0.028초

Semantic Network Analysis on the MIS Research Keywords: APJIS and MIS Quarterly 2005~2009

  • Lee, Sung-Joon;Choi, Jun-Ho;Kim, Hee-Woong
    • Asia pacific journal of information systems
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    • 제20권4호
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    • pp.25-51
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    • 2010
  • This study compares and contrasts the intellectual development of the MIS field in Korea from 2005 to 2009 to that of international trends by using a keyword co-occurrence network analysis of the two flagship journals: APJIS and MIS Quarterly. From 316 research articles in these two journals, 132 unique and most frequently co-occurred keywords were put into analysis. The results of structural equivalence show a mild correlation between APJIS and MIS Quarterly. The e-commerce, trust, and technology adoption are the high frequency keywords in both journals. In Korea e-learning, purchasing, and recommendation systems turn out to be important keywords while outsourcing, research method, quantitative method, design research, information theory, and empirical research are in average international journals. This connotes that the Korean scholarship tends to focus more on practically oriented topics, but the clustering and relational mapping of research topics in each journal show a mild level of overlap with distinctive orientations due to intrinsic disparities depending on the concerned journals' geographical scopes, namely domestic or global.

동시단어분석을 이용한 품질경영분야 지식구조 분석 (The Analysis of Knowledge Structure using Co-word Method in Quality Management Field)

  • 박만희
    • 품질경영학회지
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    • 제44권2호
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    • pp.389-408
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    • 2016
  • Purpose: This study was designed to analyze the behavioral change of knowledge structures and the trends of research topics in the quality management field. Methods: The network structure and knowledge structure of the words were visualized in map form using co-word analysis, cluster analysis and strategic diagram. Results: Summarizing the research results obtained in this study are as follows. First, the word network derived from co-occurrence matrix had 106 nodes and 5,314 links and its density was analyzed to 0.95. Average betweenness centrality of word network was 2.37. In addition, average closeness centrality and average eigenvector centrality of word network were 0.01. Second, by applying optimal criteria of cluster decision and K-means algorithm to word co-occurrence matrix, 106 words were grouped into seven clusters such as standard & efficiency, product design, reliability, control chart, quality model, 6 sigma, and service quality. Conclusion: According to the results of strategic diagram analysis over time, the traditional research topics of quality management field related to reliability, 6 sigma, control chart topics in the third quadrant were revealed to be declined for their study importance. Research topics related to product design and customer satisfaction were found to be an important research topic over analysis periods. Research topic related to management innovation was emerging state and the scope of research topics related to process model was extended to research topics with system performance. Research topic related to service quality located in the first quadrant was analyzed as the key research topic.

DEVELOPMENT OF A PRACTICAL METHOD FOR THE ESTIMATION OF WELD INDUCED CRACK IN THICK PLATE WELDMENTS

  • Lee, Jae-Myung;Yoon, Dong-Ryul;Heo, Hee-Young;Jang, Tae-Won;Lee, Jae-Won
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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    • pp.396-401
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    • 2002
  • A practical method for evaluating the possibility of the occurrence of cracking in actual thick-plate T-joint weldments is presented in this study. Systematic experiments based on the method of the design of experiment are conducted in order to investigate the crack tendency in relation to typical welding parameters such as diffusible hydrogen, restraint intensity, preheating temperature and so on. The elastic analysis using the [mite element techniques is employed to quantify the restraint intensities of the specimens. The defined restraint intensities are treated in numerical way for the sake of considering the most uncertain factor among some major factors that govern the cracking phenomena due to welding. The critical plane for judgment of the crack occurrence or crack density is presented as a function of typical welding parameters including determined restraint intensities. The results of numerical estimation by the proposed method for the experimental specimens show the usefulness as a practical tool in welding induced crack problem having extensive uncertainties.

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Color Texture Analysis as a Tool for Quantitative Evaluation of Radiation-Induced Skin Injuries

  • Sung Young Lee;Jin Ho Kim;Ji Hyun Chang;Jong Min Park;Chang Heon Choi;Jung-in Kim;So-Yeon Park
    • Journal of Radiation Protection and Research
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    • 제48권3호
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    • pp.144-152
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    • 2023
  • Background: Color texture analysis was applied as a tool for quantitative evaluation of radiation-induced skin injuries. Materials and Methods: We prospectively selected 20 breast cancer patients who underwent whole-breast radiotherapy after breast-conserving surgery. Color images of skin surfaces for irradiated breasts were obtained by using a mobile skin analyzer. The first skin measurement was performed before the first fraction of radiotherapy, and the subsequent measurement was conducted approximately 10 days after the completion of the entire series of radiotherapy sessions. For comparison, color images of the skin surface for the unirradiated breasts were measured similarly. For each color image, six co-occurrence matrices (red-green [RG], red-blue [RB], and green-blue [GB] from color channels, red [R], green [G], blue [B] from gray channels) can be generated. Four textural features (contrast, correlation, energy, and homogeneity) were calculated for each co-occurrence matrix. Finally, several statistical analyses were used to investigate the performance of the color textural parameters to objectively evaluate the radiation-induced skin damage. Results and Discussion: For the R channel from the gray channel, the differences in the values between the irradiated and unirradiated skin were larger than those of the G and B channels. In addition, for the RG and RB channels, where R was considered in the color channel, the differences were larger than those in the GB channel. When comparing the relative values between gray and color channels, the 'contrast' values for the RG and RB channels were approximately two times greater than those for the R channel for irradiated skin. In contrast, there were no noticeable differences for unirradiated skin. Conclusion: The utilization of color texture analysis has shown promising results in evaluating the severity of skin damage caused by radiation. All textural parameters of the RG and RB co-occurrence matrices could be potential indicators of the extent of skin damage caused by radiation.

Texture Analysis for Classifying Normal Tissue, Benign and Malignant Tumors from Breast Ultrasound Image

  • Eom, Sang-Hee;Ye, Soo-Young
    • Journal of information and communication convergence engineering
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    • 제20권1호
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    • pp.58-64
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    • 2022
  • Breast ultrasonic reading is critical as a primary screening test for the early diagnosis of breast cancer. However, breast ultrasound examinations show significant differences in diagnosis based on the difference in image quality according to the ultrasonic equipment, experience, and proficiency of the examiner. Accordingly, studies are being actively conducted to analyze the texture characteristics of normal breast tissue, positive tumors, and malignant tumors using breast ultrasonography and to use them for computer-assisted diagnosis. In this study, breast ultrasonography was conducted to select 247 ultrasound images of 71 normal breast tissues, 87 fibroadenomas among benign tumors, and 89 malignant tumors. The selected images were calculated using a statistical method with 21 feature parameters extracted using the gray level co-occurrence matrix algorithm, and classified as normal breast tissue, benign tumor, and malignancy. In addition, we proposed five feature parameters that are available for computer-aided diagnosis of breast cancer classification. The average classification rate for normal breast tissue, benign tumors, and malignant tumors, using this feature parameter, was 82.8%.

한국 사회의 불평등 관련 연구 동향 분석안 (Analysis of Research Trends in Inequality of Korean Society)

  • 김용환
    • 한국문헌정보학회지
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    • 제55권2호
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    • pp.263-287
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    • 2021
  • 한국사회의 불평등과 관련된 연구는 다양한 영역에서 산발적으로 진행되어 왔다. 이 연구에서는 불평등 관련 연구 동향을 한국학술지인용색인을 통해 수집한 논문 데이터를 활용하여 기초 통계 분석, 단어 동시 출현 분석, 주 경로 분석을 통해 통합적으로 분석하였다. 기초 통계 분석을 통해 핵심저자, 저널, 논문을 파악할 수 있었다. 동시출현 분석을 통해 소득불평등, 교육불평등, 복지불평등, 불평등 정책이 핵심 주제로 확인되었다. 주 경로 분석을 통해 2004년 이후의 불평등 연구 흐름은 두 가지로 나타났다. 하나는 경제적 불평등에 관한 연구이고, 다른 하나는 건강 불평등 및 사회 구조적 불평등과 관련된 연구로 나타났다.

An Action Unit co-occurrence constraint 3DCNN based Action Unit recognition approach

  • Jia, Xibin;Li, Weiting;Wang, Yuechen;Hong, SungChan;Su, Xing
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권3호
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    • pp.924-942
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    • 2020
  • The facial expression is diverse and various among persons due to the impact of the psychology factor. Whilst the facial action is comparatively steady because of the fixedness of the anatomic structure. Therefore, to improve performance of the action unit recognition will facilitate the facial expression recognition and provide profound basis for the mental state analysis, etc. However, it still a challenge job and recognition accuracy rate is limited, because the muscle movements around the face are tiny and the facial actions are not obvious accordingly. Taking account of the moving of muscles impact each other when person express their emotion, we propose to make full use of co-occurrence relationship among action units (AUs) in this paper. Considering the dynamic characteristic of AUs as well, we adopt the 3D Convolutional Neural Network(3DCNN) as base framework and proposed to recognize multiple action units around brows, nose and mouth specially contributing in the emotion expression with putting their co-occurrence relationships as constrain. The experiments have been conducted on a typical public dataset CASME and its variant CASME2 dataset. The experiment results show that our proposed AU co-occurrence constraint 3DCNN based AU recognition approach outperforms current approaches and demonstrate the effectiveness of taking use of AUs relationship in AU recognition.

공기 정보를 이용한 비정상 SIP 패킷 공격탐지 기법 (Abnormal SIP Packet Detection Mechanism using Co-occurrence Information)

  • 김득용;이형우
    • 한국산학기술학회논문지
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    • 제11권1호
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    • pp.130-140
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    • 2010
  • SIP(Session Initiation Protocol)는 IP 기반의 VoIP(Voice over IP) 서비스를 실현하기 위한 시그널링 프로토콜이다. 그러나 SIP 프로토콜은 기존의 IP 망을 활용하기 때문에 많은 보안 취약점이 존재한다. 특히 SIP 헤더의 정보를 변경하여 전송하는 SIP Malformed 메시지 공격 같은 경우 VoIP 서비스의 오작동을 유발하거나, 악성코드를 삽입하여 SIP 클라이언트 시스템내 개인정보를 유출하는 등 심각한 문제점을 보이고 있어 이에 대한 대체 방안이 제시되어야 한다. 이에 본 논문에서는 SIP Malformed 메시지 공격탐지에 대한 기존의 연구를 분석하고, 언어 처리에서 단어의 연관성을 분석하는 기법으로 사용되는 공기 정보(Co-occurrence Information)와 네트워크에서 발생하는 실제 SIP 세션 상태 정보를 반영하여 SIP 연관규칙 패턴을 생성하는 기법을 제안하였다. 본 논문에서 제안한 공기정보 기반 SIP 연관규칙 패턴을 이용하여 SIP 비정상메시지 공격을 탐지한 결과 평균 87%의 탐지율을 보였다.

칼라 영역의 크기와 뭉침을 기술하는 칼라 동시발생 히스토그램을 이용한 영상검색 (Image Retrieval Using the Color Co-occurrence Histogram Describing the Size and Coherence of the Homogeneous Color Region)

  • 안명석;조석제
    • 정보처리학회논문지B
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    • 제13B권3호
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    • pp.275-282
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    • 2006
  • 칼라 영상을 효과적으로 검색하기 위해 칼라의 분포와 화소 간 위치 정보를 이용하여 영상을 검색하는 방법이 연구되었다. 본 논문에서는 적은 빈 개수로 칼라 분포와 화소 간 위치 정보를 효율적으로 기술하여 영상을 검색할 수 있는 기술자를 제안한다. 이는 칼라 동시발생 히스토그램의 대각성분과 비 대각성분에 가중치를 주어 에너지를 변형하고, 의미가 약한 값의 빈을 제거한 것이다. 분석을 통해 칼라 동시발생 히스토그램의 대각성분과 비 대각성분은 같은 칼라를 가지는 영역의 크기 정보와 그 영역 간의 뭉침 정보를 기술하며, 비 대각성분이 대각성분에 비해 영상검색에 더 우수한 특성을 나타낸다는 것을 확인하였다. 그래서, 비 대각성분의 가중치를 대각성분의 가중치에 비해 높게 주면 영상검색을 효과적으로 할 수 있다는 사실을 밝혔다. 64 레벨로 칼라 양자화된 RGB 칼라 좌표계에서의 실험영상에서, 가중치가 0.7에서 0.9인 제안한 기술자가 기존의 기술자에 비해 우수하게 영상을 검색함을 알 수 있었다.