• Title/Summary/Keyword: Feature representation

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Robust appearance feature learning using pixel-wise discrimination for visual tracking

  • Kim, Minji;Kim, Sungchan
    • ETRI Journal
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    • v.41 no.4
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    • pp.483-493
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    • 2019
  • Considering the high dimensions of video sequences, it is often challenging to acquire a sufficient dataset to train the tracking models. From this perspective, we propose to revisit the idea of hand-crafted feature learning to avoid such a requirement from a dataset. The proposed tracking approach is composed of two phases, detection and tracking, according to how severely the appearance of a target changes. The detection phase addresses severe and rapid variations by learning a new appearance model that classifies the pixels into foreground (or target) and background. We further combine the raw pixel features of the color intensity and spatial location with convolutional feature activations for robust target representation. The tracking phase tracks a target by searching for frame regions where the best pixel-level agreement to the model learned from the detection phase is achieved. Our two-phase approach results in efficient and accurate tracking, outperforming recent methods in various challenging cases of target appearance changes.

A Morpheme-unit Korean Feature-Based Brammer (KFG) with the X-bar Theoretic Notion of Headedness (X-바 이론의 중심어 개념을 도입한 형태소 단위의 한국어 자질 기반 문법)

  • Park, So-Yeong;Hwang, Yeong-Suk;Im, Hae-Chang
    • Journal of KIISE:Software and Applications
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    • v.26 no.10
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    • pp.1247-1259
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    • 1999
  • 본 논문에서는 한국어 문장형성원리를 간결하게 제시할 수 있도록 X-바 이론의 중심어 개념을 도입한 한국어 자질기반 문법을 제안한다. 제안하는 문법은 어절에 관계없이 나타나는 한국어의 문법현상을 명확히 설명할 수 있도록 어절 대신 형태소를 기본단위로 한다. 그리고, 한국어의 구문범주가 지닌 의미정보와 기능정보를 자질을 이용하여 독립적으로 표현하며, 구문범주간의 결합관계를 바탕으로 하는 자질연산을 수행하여 문장을 분석한다. 또한, 한국어의 부분자유어순과 생략현상에 대해 견고하게 분석할 수 있도록 자질연산을 이진결합중심의 CNF(Chomsky Normal Form)로 제한한다. 이렇게 구성된 한국어 자질기반 문법은 규칙을 직관적이고도 간단하게 기술하며, 한국어의 다양한 문장들을 견고하게 분석한다. SERI Test Suites 97과 신문기사에서 746문장을 추출하여 실험한 결과 94%~99%의 적용율을 보였다.Abstract In this paper, we propose a Korean feature-based grammar(KFG) which adopts the X-bar theoretic notion of headedness for a precise representation of Korean syntactic structure. In order to explain various language phenomena in a given sentence, we use not the word but the morpheme as a constituent unit of KFG. We use features manifesting both the syntactic information and the semantic information of Korean syntactic categories, and feature operations based on the association relationship between two categories. In addition, we restrict feature operations to CNF(Chomsky Normal Form) binary form, which provides a robust representation for properties in Korean such as the frequent ellipsis and the partial free-order. The KFG is intuitive, simple, and versatile in representing most Korean sentences. The experimental result shows 94%~99% coverage on 746 sentences extracted from SERI Test Suites 97 and newspaper sentences.

Face Image Synthesis using Nonlinear Manifold Learning (비선형 매니폴드 학습을 이용한 얼굴 이미지 합성)

  • 조은옥;김대진;방승양
    • Journal of KIISE:Software and Applications
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    • v.31 no.2
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    • pp.182-188
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    • 2004
  • This paper proposes to synthesize facial images from a few parameters for the pose and the expression of their constituent components. This parameterization makes the representation, storage, and transmission of face images effective. But it is difficult to parameterize facial images because variations of face images show a complicated nonlinear manifold in high-dimensional data space. To tackle this problem, we use an LLE (Locally Linear Embedding) technique for a good representation of face images, where the relationship among face images is preserving well and the projected manifold into the reduced feature space becomes smoother and more continuous. Next, we apply a snake model to estimate face feature values in the reduced feature space that corresponds to a specific pose and/or expression parameter. Finally, a synthetic face image is obtained from an interpolation of several neighboring face images in the vicinity of the estimated feature value. Experimental results show that the proposed method shows a negligible overlapping effect and creates an accurate and consistent synthetic face images with respect to changes of pose and/or expression parameters.

Improved Fault Detection Based on One-Class Classification and Feature Selection (단일 클래스 분류와 특징 선택에 기반한 향상된 이상 감지)

  • Cho, Hyun-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.8
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    • pp.216-223
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    • 2019
  • Fault detection during production processes is one of the required operational tasks to run production processes both safely and consistently. Unexpected operational events or undetected process faults can have a serious impact on the production systems and subsequently on the final products' quality. In addition, such situations may lead to malfunctions or breakdowns of production processes. To reliably detect such abnormalities, a new one-class classification-based detection scheme has recently been developed The proposed method consists of four steps:1) noise filtering, 2) feature selection, 3) nonlinear representation and 4) outlier detection. The performance of the proposed scheme was demonstrated using the multivariate data obtained from a simulation process. The results have shown that the proposed method produced reliable monitoring results and outperforms any existing methods with an average improvement of 25.4%. The use of proper feature selection in the proposed framework yielded better detection performance.

Comparisons of Linear Feature Extraction Methods (선형적 특징추출 방법의 특성 비교)

  • Oh, Sang-Hoon
    • The Journal of the Korea Contents Association
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    • v.9 no.4
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    • pp.121-130
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    • 2009
  • In this paper, feature extraction methods, which is one field of reducing dimensions of high-dimensional data, are empirically investigated. We selected the traditional PCA(Principal Component Analysis), ICA(Independent Component Analysis), NMF(Non-negative Matrix Factorization), and sNMF(Sparse NMF) for comparisons. ICA has a similar feature with the simple cell of V1. NMF implemented a "parts-based representation in the brain" and sNMF is a improved version of NMF. In order to visually investigate the extracted features, handwritten digits are handled. Also, the extracted features are used to train multi-layer perceptrons for recognition test. The characteristic of each feature extraction method will be useful when applying feature extraction methods to many real-world problems.

Cross-architecture Binary Function Similarity Detection based on Composite Feature Model

  • Xiaonan Li;Guimin Zhang;Qingbao Li;Ping Zhang;Zhifeng Chen;Jinjin Liu;Shudan Yue
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.8
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    • pp.2101-2123
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    • 2023
  • Recent studies have shown that the neural network-based binary code similarity detection technology performs well in vulnerability mining, plagiarism detection, and malicious code analysis. However, existing cross-architecture methods still suffer from insufficient feature characterization and low discrimination accuracy. To address these issues, this paper proposes a cross-architecture binary function similarity detection method based on composite feature model (SDCFM). Firstly, the binary function is converted into vector representation according to the proposed composite feature model, which is composed of instruction statistical features, control flow graph structural features, and application program interface calling behavioral features. Then, the composite features are embedded by the proposed hierarchical embedding network based on a graph neural network. In which, the block-level features and the function-level features are processed separately and finally fused into the embedding. In addition, to make the trained model more accurate and stable, our method utilizes the embeddings of predecessor nodes to modify the node embedding in the iterative updating process of the graph neural network. To assess the effectiveness of composite feature model, we contrast SDCFM with the state of art method on benchmark datasets. The experimental results show that SDCFM has good performance both on the area under the curve in the binary function similarity detection task and the vulnerable candidate function ranking in vulnerability search task.

Vehicle Recognition using Non-negative Tensor Factorization (비음수 텐서 분해를 이용한 차량 인식)

  • Ban, Jae Min;Kang, Hyunchul
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.5
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    • pp.136-146
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    • 2015
  • The active control of a vehicle based on vehicle recognition is one of key technologies for the intelligent vehicle, and the part-based image representation is necessary to recognize vehicles with only partial shapes of vehicles especially in urban scene where occlusions frequently occur. In this paper, we implemented a part-based image representation scheme using non-negative tensor factorization(NTF) and realized a robust vehicle recognition system using the NTF feature. The result shows that the proposed method gives more intuitive part-based representation and more robust recognition in urban scene.

A Study on Speaker Identification Using Hybrid Neural Network (하이브리드 신경회로망을 이용한 화자인식에 관한 연구)

  • Shin, Chung-Ho;Shin, Dea-Kyu;Lee, Jea-Hyuk;Park, Sang-Hee
    • Proceedings of the KIEE Conference
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    • 1997.11a
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    • pp.600-602
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    • 1997
  • In this study, a hybrid neural net consisting of an Adaptive LVQ(ALVQ) algorithm and MLP is proposed to perform speaker identification task. ALVQ is a new learning procedure using adaptively feature vector sequence instead of only one feature vector in training codebooks initialized by LBG algorithm and the optimization criterion of this method is consistent with the speaker classification decision rule. ALVQ aims at providing a compressed, geometrically consistent data representation. It is fit to cover irregular data distributions and computes the distance of the input vector sequence from its nodes. On the other hand, MLP aim at a data representation to fit to discriminate patterns belonging to different classes. It has been shown that MLP nets can approximate Bayesian "optimal" classifiers with high precision, and their output values can be related a-posteriori class probabilities. The different characteristics of these neural models make it possible to devise hybrid neural net systems, consisting of classification modules based on these two different philosophies. The proposed method is compared with LBG algorithm, LVQ algorithm and MLP for performance.

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