• Title/Summary/Keyword: Collaborative representation method

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Facial Gender Recognition via Low-rank and Collaborative Representation in An Unconstrained Environment

  • Sun, Ning;Guo, Hang;Liu, Jixin;Han, Guang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.9
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    • pp.4510-4526
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    • 2017
  • Most available methods of facial gender recognition work well under a constrained situation, but the performances of these methods have decreased significantly when they are implemented under unconstrained environments. In this paper, a method via low-rank and collaborative representation is proposed for facial gender recognition in the wild. Firstly, the low-rank decomposition is applied to the face image to minimize the negative effect caused by various corruptions and dynamical illuminations in an unconstrained environment. And, we employ the collaborative representation to be as the classifier, which using the much weaker $l_2-norm$ sparsity constraint to achieve similar classification results but with significantly lower complexity. The proposed method combines the low-rank and collaborative representation to an organic whole to solve the task of facial gender recognition under unconstrained environments. Extensive experiments on three benchmarks including AR, CAS-PERL and YouTube are conducted to show the effectiveness of the proposed method. Compared with several state-of-the-art algorithms, our method has overwhelming superiority in the aspects of accuracy and robustness.

An improved kernel principal component analysis based on sparse representation for face recognition

  • Huang, Wei;Wang, Xiaohui;Zhu, Yinghui;Zheng, Gengzhong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.6
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    • pp.2709-2729
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    • 2016
  • Representation based classification, kernel method and sparse representation have received much attention in the field of face recognition. In this paper, we proposed an improved kernel principal component analysis method based on sparse representation to improve the accuracy and robustness for face recognition. First, the distances between the test sample and all training samples in kernel space are estimated based on collaborative representation. Second, S training samples with the smallest distances are selected, and Kernel Principal Component Analysis (KPCA) is used to extract the features that are exploited for classification. The proposed method implements the sparse representation under ℓ2 regularization and performs feature extraction twice to improve the robustness. Also, we investigate the relationship between the accuracy and the sparseness coefficient, the relationship between the accuracy and the dimensionality respectively. The comparative experiments are conducted on the ORL, the GT and the UMIST face database. The experimental results show that the proposed method is more effective and robust than several state-of-the-art methods including Sparse Representation based Classification (SRC), Collaborative Representation based Classification (CRC), KCRC and Two Phase Test samples Sparse Representation (TPTSR).

An Analysis of Collaborative Visualization Processing of Text Information for Developing e-Learning Contents

  • SUNG, Eunmo
    • Educational Technology International
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    • v.10 no.1
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    • pp.25-40
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    • 2009
  • The purpose of this study was to explore procedures and modalities on collaborative visualization processing of text information for developing e-Learning contents. In order to investigate, two research questions were explored: 1) what are procedures on collaborative visualization processing of text information, 2) what kinds of patterns and modalities can be found in each procedure of collaborative visualization of text information. This research method was employed a qualitative research approaches by means of grounded theory. As a result of this research, collaborative visualization processing of text information were emerged six steps: identifying text, analyzing text, exploring visual clues, creating visuals, discussing visuals, elaborating visuals, and creating visuals. Collaborative visualization processing of text information came out the characteristic of systemic and systematic system like spiral sequencing. Also, another result of this study, modalities in collaborative visualization processing of text information was divided two dimensions: individual processing by internal representation, social processing by external representation. This case study suggested that collaborative visualization strategy has full possibility of providing ideal methods for sharing cognitive system or thinking system as using human visual intelligence.

Weighted Collaborative Representation and Sparse Difference-Based Hyperspectral Anomaly Detection

  • Wang, Qianghui;Hua, Wenshen;Huang, Fuyu;Zhang, Yan;Yan, Yang
    • Current Optics and Photonics
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    • v.4 no.3
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    • pp.210-220
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    • 2020
  • Aiming at the problem that the Local Sparse Difference Index algorithm has low accuracy and low efficiency when detecting target anomalies in a hyperspectral image, this paper proposes a Weighted Collaborative Representation and Sparse Difference-Based Hyperspectral Anomaly Detection algorithm, to improve detection accuracy for a hyperspectral image. First, the band subspace is divided according to the band correlation coefficient, which avoids the situation in which there are multiple solutions of the sparse coefficient vector caused by too many bands. Then, the appropriate double-window model is selected, and the background dictionary constructed and weighted according to Euclidean distance, which reduces the influence of mixing anomalous components of the background on the solution of the sparse coefficient vector. Finally, the sparse coefficient vector is solved by the collaborative representation method, and the sparse difference index is calculated to complete the anomaly detection. To prove the effectiveness, the proposed algorithm is compared with the RX, LRX, and LSD algorithms in simulating and analyzing two AVIRIS hyperspectral images. The results show that the proposed algorithm has higher accuracy and a lower false-alarm rate, and yields better results.

Robust Face Recognition under Limited Training Sample Scenario using Linear Representation

  • Iqbal, Omer;Jadoon, Waqas;ur Rehman, Zia;Khan, Fiaz Gul;Nazir, Babar;Khan, Iftikhar Ahmed
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.7
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    • pp.3172-3193
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    • 2018
  • Recently, several studies have shown that linear representation based approaches are very effective and efficient for image classification. One of these linear-representation-based approaches is the Collaborative representation (CR) method. The existing algorithms based on CR have two major problems that degrade their classification performance. First problem arises due to the limited number of available training samples. The large variations, caused by illumintion and expression changes, among query and training samples leads to poor classification performance. Second problem occurs when an image is partially noised (contiguous occlusion), as some part of the given image become corrupt the classification performance also degrades. We aim to extend the collaborative representation framework under limited training samples face recognition problem. Our proposed solution will generate virtual samples and intra-class variations from training data to model the variations effectively between query and training samples. For robust classification, the image patches have been utilized to compute representation to address partial occlusion as it leads to more accurate classification results. The proposed method computes representation based on local regions in the images as opposed to CR, which computes representation based on global solution involving entire images. Furthermore, the proposed solution also integrates the locality structure into CR, using Euclidian distance between the query and training samples. Intuitively, if the query sample can be represented by selecting its nearest neighbours, lie on a same linear subspace then the resulting representation will be more discriminate and accurately classify the query sample. Hence our proposed framework model the limited sample face recognition problem into sufficient training samples problem using virtual samples and intra-class variations, generated from training samples that will result in improved classification accuracy as evident from experimental results. Moreover, it compute representation based on local image patches for robust classification and is expected to greatly increase the classification performance for face recognition task.

PLCS-based Architecture and Operation Method for Interoperability in SBA Integrated Collaborative Environment (상호운용성 제공을 위한 PLCS 기반 SBA 통합협업환경 아키텍처 및 운용 방안)

  • Kim, Hwang-Ho;Choi, Jin-Young;Wang, Ji-Nam
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.33 no.3
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    • pp.87-92
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    • 2010
  • In this paper, we suggest a PLCS-based architecture and operation method for providing interoperability in SBA integrated collaborative environment. Specifically, the suggested architecture is based on the distributed collaborative environment which employes the PLCS application protocol and integrated repository for representing and sharing product data information between collaborators remotely located. As an example of data representation, a military vehicle system is considered and two kinds of information, including state and activity/process, are explained. We expect that the suggested architecture can be used as a reference model to develop an efficient SBA integrated collaborative environment.

Optimal sensor placement for health monitoring of high-rise structure based on collaborative-climb monkey algorithm

  • Yi, Ting-Hua;Zhou, Guang-Dong;Li, Hong-Nan;Zhang, Xu-Dong
    • Structural Engineering and Mechanics
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    • v.54 no.2
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    • pp.305-317
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    • 2015
  • Optimal sensor placement (OSP) is an integral component in the design of an effective structural health monitoring (SHM) system. This paper describes the implementation of a novel collaborative-climb monkey algorithm (CMA), which combines the artificial fish swarm algorithm (AFSA) with the monkey algorithm (MA), as a strategy for the optimal placement of a predefined number of sensors. Different from the original MA, the dual-structure coding method is adopted for the representation of design variables. The collaborative-climb process that can make the full use of the monkeys' experiences to guide the movement is proposed and incorporated in the CMA to speed up the search efficiency of the algorithm. The effectiveness of the proposed algorithm is demonstrated by a numerical example with a high-rise structure. The results show that the proposed CMA algorithm can provide a robust design for sensor networks, which exhibits superior convergence characteristics when compared to the original MA using the dual-structure coding method.

Adaptive Hyperspectral Image Classification Method Based on Spectral Scale Optimization

  • Zhou, Bing;Bingxuan, Li;He, Xuan;Liu, Hexiong
    • Current Optics and Photonics
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    • v.5 no.3
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    • pp.270-277
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    • 2021
  • The adaptive sparse representation (ASR) can effectively combine the structure information of a sample dictionary and the sparsity of coding coefficients. This algorithm can effectively consider the correlation between training samples and convert between sparse representation-based classifier (SRC) and collaborative representation classification (CRC) under different training samples. Unlike SRC and CRC which use fixed norm constraints, ASR can adaptively adjust the constraints based on the correlation between different training samples, seeking a balance between l1 and l2 norm, greatly strengthening the robustness and adaptability of the classification algorithm. The correlation coefficients (CC) can better identify the pixels with strong correlation. Therefore, this article proposes a hyperspectral image classification method called correlation coefficients and adaptive sparse representation (CCASR), based on ASR and CC. This method is divided into three steps. In the first step, we determine the pixel to be measured and calculate the CC value between the pixel to be tested and various training samples. Then we represent the pixel using ASR and calculate the reconstruction error corresponding to each category. Finally, the target pixels are classified according to the reconstruction error and the CC value. In this article, a new hyperspectral image classification method is proposed by fusing CC and ASR. The method in this paper is verified through two sets of experimental data. In the hyperspectral image (Indian Pines), the overall accuracy of CCASR has reached 0.9596. In the hyperspectral images taken by HIS-300, the classification results show that the classification accuracy of the proposed method achieves 0.9354, which is better than other commonly used methods.

Analysis of Representations in the Problem-Solving Process: The ACODESA (Collaborative Learning, Scientific Debate and Self Reflection) Method (ACODESA(Collaborative Learning, Scientific Debate and Self Reflection) 방법을 적용한 문제해결 과정에서 나타난 표상의 분석)

  • Kang, Young Ran;Cho, Cheong Soo
    • Education of Primary School Mathematics
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    • v.18 no.3
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    • pp.203-216
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    • 2015
  • This study analyzed changes of representations which had come up in the problem-solving process of math-gifted 6th grade students that ACODESA had been applied. The class was designed on a ACODESA procedure that enhancing the use of varied representations, and conducted for 40minutes, 4 times over the period. The recorded videos and interviews with the students were transcribed for analysing data. According to the result of the analysis, which adopted Despina's using type of representation, there appeared types of 'adding', 'elaborating', and 'reducing'. This study found that there is need for a class design that can make personal representations into that of public through small group discussions and confirmation in the problem-solving process.

A Hybrid Recommendation System based on Fuzzy C-Means Clustering and Supervised Learning

  • Duan, Li;Wang, Weiping;Han, Baijing
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.7
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    • pp.2399-2413
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    • 2021
  • A recommendation system is an information filter tool, which uses the ratings and reviews of users to generate a personalized recommendation service for users. However, the cold-start problem of users and items is still a major research hotspot on service recommendations. To address this challenge, this paper proposes a high-efficient hybrid recommendation system based on Fuzzy C-Means (FCM) clustering and supervised learning models. The proposed recommendation method includes two aspects: on the one hand, FCM clustering technique has been applied to the item-based collaborative filtering framework to solve the cold start problem; on the other hand, the content information is integrated into the collaborative filtering. The algorithm constructs the user and item membership degree feature vector, and adopts the data representation form of the scoring matrix to the supervised learning algorithm, as well as by combining the subjective membership degree feature vector and the objective membership degree feature vector in a linear combination, the prediction accuracy is significantly improved on the public datasets with different sparsity. The efficiency of the proposed system is illustrated by conducting several experiments on MovieLens dataset.