• 제목/요약/키워드: local embedding

검색결과 63건 처리시간 0.027초

Robust ROI Watermarking Scheme Based on Visual Cryptography: Application on Mammograms

  • Benyoussef, Meryem;Mabtoul, Samira;El Marraki, Mohamed;Aboutajdine, Driss
    • Journal of Information Processing Systems
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    • 제11권4호
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    • pp.495-508
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    • 2015
  • In this paper, a novel robust medical images watermarking scheme is proposed. In traditional methods, the added watermark may alter the host medical image in an irreversible manner and may mask subtle details. Consequently, we propose a method for medical image copyright protection that may remedy this problem by embedding the watermark without modifying the original host image. The proposed method is based on the visual cryptography concept and the dominant blocks of wavelet coefficients. The logic in using the blocks dominants map is that local features, such as contours or edges, are unique to each image. The experimental results show that the proposed method can withstand several image processing attacks such as cropping, filtering, compression, etc.

발톱에 발생한 역행조갑 환자의 치험례 (A Case of Retronychia on Toenail)

  • 최석민;김철한;강상규;탁민성
    • Archives of Plastic Surgery
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    • 제37권2호
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    • pp.178-181
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    • 2010
  • Purpose: Retronychia is the embedding of the nail into proximal nail fold. Retronychia starts with disruption of the longitudinal growth of the nail. With the growth of a new nail, the old one is pushed upwards and backwards. This leads to embedding of the top nail into the ventral aspect of the proximal nail fold and results with chronic paronychia. We present a case of retronychia that was rarely reported in the literature. Methods: A 46-year old female presented with a 3-month history of painful right first, 2nd, 3rd toenail changes. Although she was initially treated with broad spectrum antibiotics, she did not response to therapy. Later, she presented to our department because of progressively worsening pain that impaired her walking. Physical examination revealed with proximal nail fold erythema, painful swelling, yellowish nail discoloration, and distal onycholysis. Bacterial and fungus culture showed no organism. Treatment was surgical nail avulsion under local anesthesia. Results: The postoperative course was uneventful. 10 months later, the patient had a normal growing nail and was free of symptoms. Conclusion: We report a case of retronychia on toenail. Retronychia is a proximal nail plate ingrowth into the proximal nail fold which is associated with multiple generations of nail plate misaligned beneath the proximal nail. Management consisted of simple avulsion of superimposed nail. Retronychia is suspected with a persistent paronychia, particularly in the setting of trauma. Avulsion of the top nail confirms the diagnosis and may be curative if the underlying nail appears healthy.

Differential Diagnosis of CT Images in Children with Neuroblastomas and Ganglioneuroblastomas

  • Zhuang, Bo;Lv, Deng-Kun;Gao, Si-Ju;Meng, Jing-Jing
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권23호
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    • pp.10509-10512
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    • 2015
  • Objective: To investigate the differential features of CT images in children with neuroblastomas (N) and ganglioneuroblastomas (G). Materials and Methods: Clinical data of 12 children in group G and 15 in group N undergoing CT examination and definitely diagnosed by pathology were retrospectively analyzed. The focal conditions were observed and compared in the two groups, including location, size, boundaries, morphology, enhanced degree and mode, abdominal vascular involvement, presence or absence of spanning the midline, infiltration of peripheral organs, angiography manifestations in tumors or surroundings, presence or absence of calcification and vascular tumor emboli as well as metastases of distal organs and lymph nodes. Results: In group N, the incidence of tumors in the adrenal area was conspicuously higher than in group G (P<0.05), while that of tumors with regular morphology and clear boundaries was significantly lower than in group G (P<0.01); Angiography manifestation rate and incidences of vascular embedding, lymph node metastasis, infiltration and organic metastasis in group N were all markedly higher than in group G (P<0.05). There was no statistical significance between the two groups in terms of focal size, presence or absence of calcification and spanning the midline, and enhanced degree and mode, as well as vascular tumor emboli (P>0.05). Conclusions: Mostly located in adrenal areas and with vascular embedding as a primary manifestation, the neuroblastoma extremely readily metastases to lymph nodes and other organs as well as infiltrating local tissues, with dilation on angiography frequent in or around the tumors. With vascular displacement as a primary manifestation, ganglioneuroblastoma has a regular morphology and clear boundaries.

지역문화와 기술이 융합된 새로운 스마트시티 구축 (Building a New Smart City: Integrating Local Culture and Technology)

  • 심기백;황우성;최명렬
    • 디지털융복합연구
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    • 제17권9호
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    • pp.193-198
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    • 2019
  • 스마트시티의 도시 환경은 최신 기술로 인해 더욱 편리해지고 있지만, 삶의 만족도는 기존 도시보다 향상되지 못하고 있다. 이는 스마트시티를 건설할 때 기술에만 집중할 뿐 지역 문화의 중요성을 간과했기 때문이다. 본 논문은 캄보디아에서 스마트시티에 적용되는 기술로 지역 문화를 활성화 할 수 있는 가능성을 모색하기 위한 연구를 진행한다. ICT, IoT 기술 등을 사용하여 다양한 문화 프로그램을 연계하는 방법 및 문화유산의 효과적 계승을 돕기 위한 플랫폼을 제안한다. 그러므로, 스마트 시티와 문화와의 융합은 지역 고유의 콘텐츠를 발전시키고 도시의 시민과 관광객의 방문을 유도하여 경제적 이익을 창출할 것이다. 또한, 사회 구성원으로서의 정체성 확립을 돕고, 첨단 기술과 지역 문화가 통합된 스마트시티 구축의 방법론은 유사한 다른 도시에 적용을 가능케 함으로 지역사회와 국제사회에 기여한다.

특징 공간상에서 의 확률적 해석에 기반한 부분 인식 기법에 관한 연구 (A partially occluded object recognition technique using a probabilistic analysis in the feature space)

  • 박보건;이경무;이상욱;이진학
    • 한국통신학회논문지
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    • 제26권11A호
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    • pp.1946-1956
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    • 2001
  • 본 논문에서는 관계 벡터 공간상의 특징 대응에 관한 확률적 해석에 기반한 새로운 부분 인식 기법을 제안한다. 효과적인 인식을 위해 물체를 관계 속성 그래프(Attributed Relational Graph; ARG)와 관계 벡터 공간들의 집합으로 표현한다. 또한 잡음이나 특징 소실로 인한 왜곡을 관계 벡터 공간에서의 관계 벡터 분포에 대한 왜곡으로 확률적으로 모델링한다. 제안하는 부분 인식 기법은 두 단계로 이루어진다. 우선 지역적인 특징(local feature)과 구조적인 일관성(structural consistency)을 사용하여 후보집합을 추출한다. 이렇게 추출된 후보집합 각각에 대해 관계 벡터 공간상에서의 에러 분석과 반복적인 voting 알고리즘을 통해 특징 소실을 검출한다. 실제 영상에 대한 실험 결과를 통해 제안한 알고리즘이 잡음이나 가리어짐이 심한 경우에도 강건한 성능을 보임을 알 수 있으며, 릴렉세이션(relaxation) 기법과 수행 시간 비교 분석을 통해 계산량 측면에서의 성능 향상을 확인할 수 있다.

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Question Similarity Measurement of Chinese Crop Diseases and Insect Pests Based on Mixed Information Extraction

  • Zhou, Han;Guo, Xuchao;Liu, Chengqi;Tang, Zhan;Lu, Shuhan;Li, Lin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제15권11호
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    • pp.3991-4010
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    • 2021
  • The Question Similarity Measurement of Chinese Crop Diseases and Insect Pests (QSM-CCD&IP) aims to judge the user's tendency to ask questions regarding input problems. The measurement is the basis of the Agricultural Knowledge Question and Answering (Q & A) system, information retrieval, and other tasks. However, the corpus and measurement methods available in this field have some deficiencies. In addition, error propagation may occur when the word boundary features and local context information are ignored when the general method embeds sentences. Hence, these factors make the task challenging. To solve the above problems and tackle the Question Similarity Measurement task in this work, a corpus on Chinese crop diseases and insect pests(CCDIP), which contains 13 categories, was established. Then, taking the CCDIP as the research object, this study proposes a Chinese agricultural text similarity matching model, namely, the AgrCQS. This model is based on mixed information extraction. Specifically, the hybrid embedding layer can enrich character information and improve the recognition ability of the model on the word boundary. The multi-scale local information can be extracted by multi-core convolutional neural network based on multi-weight (MM-CNN). The self-attention mechanism can enhance the fusion ability of the model on global information. In this research, the performance of the AgrCQS on the CCDIP is verified, and three benchmark datasets, namely, AFQMC, LCQMC, and BQ, are used. The accuracy rates are 93.92%, 74.42%, 86.35%, and 83.05%, respectively, which are higher than that of baseline systems without using any external knowledge. Additionally, the proposed method module can be extracted separately and applied to other models, thus providing reference for related research.

A New Reference Pixel Prediction for Reversible Data Hiding with Reduced Location Map

  • Chen, Jeanne;Chen, Tung-Shou;Hong, Wien;Horng, Gwoboa;Wu, Han-Yan;Shiu, Chih-Wei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권3호
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    • pp.1105-1118
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    • 2014
  • In this paper, a new reversible data hiding method based on a dual binary tree of embedding levels is proposed. Four neighborhood pixels in the upper, below, left and right of each pixel are used as reference pixels to estimate local complexity for deciding embeddable and non-embeddable pixels. The proposed method does not need to record pixels that might cause underflow, overflow or unsuitable for embedment. This can reduce the size of location map and release more space for payload. Experimental results show that the proposed method is more effective in increasing payload and improving image quality than some recently proposed methods.

Comparative Study of Dimension Reduction Methods for Highly Imbalanced Overlapping Churn Data

  • Lee, Sujee;Koo, Bonhyo;Jung, Kyu-Hwan
    • Industrial Engineering and Management Systems
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    • 제13권4호
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    • pp.454-462
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    • 2014
  • Retention of possible churning customer is one of the most important issues in customer relationship management, so companies try to predict churn customers using their large-scale high-dimensional data. This study focuses on dealing with large data sets by reducing the dimensionality. By using six different dimension reduction methods-Principal Component Analysis (PCA), factor analysis (FA), locally linear embedding (LLE), local tangent space alignment (LTSA), locally preserving projections (LPP), and deep auto-encoder-our experiments apply each dimension reduction method to the training data, build a classification model using the mapped data and then measure the performance using hit rate to compare the dimension reduction methods. In the result, PCA shows good performance despite its simplicity, and the deep auto-encoder gives the best overall performance. These results can be explained by the characteristics of the churn prediction data that is highly correlated and overlapped over the classes. We also proposed a simple out-of-sample extension method for the nonlinear dimension reduction methods, LLE and LTSA, utilizing the characteristic of the data.

Robust Image Hashing for Tamper Detection Using Non-Negative Matrix Factorization

  • Tang, Zhenjun;Wang, Shuozhong;Zhang, Xinpeng;Wei, Weimin;Su, Shengjun
    • Journal of Ubiquitous Convergence Technology
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    • 제2권1호
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    • pp.18-26
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    • 2008
  • The invariance relation existing in the non-negative matrix factorization (NMF) is used for constructing robust image hashes in this work. The image is first re-scaled to a fixed size. Low-pass filtering is performed on the luminance component of the re-sized image to produce a normalized matrix. Entries in the normalized matrix are pseudo-randomly re-arranged under the control of a secret key to generate a secondary image. Non-negative matrix factorization is then performed on the secondary image. As the relation between most pairs of adjacent entries in the NMF's coefficient matrix is basically invariant to ordinary image processing, a coarse quantization scheme is devised to compress the extracted features contained in the coefficient matrix. The obtained binary elements are used to form the image hash after being scrambled based on another key. Similarity between hashes is measured by the Hamming distance. Experimental results show that the proposed scheme is robust against perceptually acceptable modifications to the image such as Gaussian filtering, moderate noise contamination, JPEG compression, re-scaling, and watermark embedding. Hashes of different images have very low collision probability. Tampering to local image areas can be detected by comparing the Hamming distance with a predetermined threshold, indicating the usefulness of the technique in digital forensics.

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Histomorphological changes in the common carotid artery of the male rat in induced hypogonadism

  • Cheruiyot, Isaac;Olabu, Beda;Kamau, Martin;Ongeti, Kevin;Mandela, Pamela
    • Anatomy and Cell Biology
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    • 제51권4호
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    • pp.284-291
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    • 2018
  • The role of androgens in the development of cardiovascular diseases remains controversial. The current study therefore sought to determine the changes in the histomorphology of the common carotid artery of the male rat in orchidectomy-induced hypogonadism. Twenty-two Rattus norvegicus male rats aged 2 months were used. The rats were randomly assigned into baseline (n=4), experimental (n=9), and control (n=9) groups. Hypogonadism was surgically induced in the experimental group by bilateral orchiectomy under local anesthesia. At experiment weeks 3, 6, and 9, three rats from each group (experimental and control) were euthanized, their common carotid artery harvested, and routine processing was done for paraffin embedding, sectioning, and staining. The photomicrographs were taken using a digital photomicroscope for morphometric analysis. Orchidectomy resulted in the development of vascular fibrosis, with a significant increase in collagen fiber density and decrease in smooth muscle and elastic fiber density. Moreover, there was development of intimal hyperplasia, with fragmentation of medial elastic lamellae in the common carotid artery of the castrated rats. Orchidectomy induces adverse changes in structure of the common carotid artery of the male rat. These changes may impair vascular function, therefore constituting a possible structural basis for the higher incidences of cardiovascular diseases observed in hypogonadism.