120 research outputs found
Face Anti-Spoofing by Learning Polarization Cues in a Real-World Scenario
Face anti-spoofing is the key to preventing security breaches in biometric
recognition applications. Existing software-based and hardware-based face
liveness detection methods are effective in constrained environments or
designated datasets only. Deep learning method using RGB and infrared images
demands a large amount of training data for new attacks. In this paper, we
present a face anti-spoofing method in a real-world scenario by automatic
learning the physical characteristics in polarization images of a real face
compared to a deceptive attack. A computational framework is developed to
extract and classify the unique face features using convolutional neural
networks and SVM together. Our real-time polarized face anti-spoofing (PAAS)
detection method uses a on-chip integrated polarization imaging sensor with
optimized processing algorithms. Extensive experiments demonstrate the
advantages of the PAAS technique to counter diverse face spoofing attacks
(print, replay, mask) in uncontrolled indoor and outdoor conditions by learning
polarized face images of 33 people. A four-directional polarized face image
dataset is released to inspire future applications within biometric
anti-spoofing field.Comment: 14pages,8figure
Measuring The User Experience And Its Importance To Customer Satisfaction: An Empirical Stusy For Telecom e-Service Websites
In telecom settings, using e-service website has become an increasingly common activity among mobile users. As an important channel, website users experience that quality plays a key role for e-service or business successes. With the use of an online structured questionnaire, a total of 20,040 were surveyed to answer the questions in thirty-one provinces in China. With methods of Principal Component Analysis, a five-factor e-service website user experience questionnaire was examined, and the factors of perceived functional completion, perceived websites performance, quality of interface and interaction, quality of content and information, and quality of online customer support or service were found effectively to measure e-service website user experience quality. In addition, all of these five aspects in e-service website user experience were found to be significant in predicting overall customer satisfaction
Unsupervised Feature Selection Algorithm via Local Structure Learning and Kernel Function
In order to reduce dimensionality of high-dimensional data, a series of feature selection algorithms have been proposed. But these algorithms have the following disadvantages: (1) they do not fully consider the nonlinear relationship between data features (2) they do not consider the similarity between data features. To solve the above two problems, we propose an unsupervised feature selection algorithm based on local structure learning and kernel function. First, through the kernel function, we map each feature of the data to the kernel space, so that the nonlinear relationship of the data features can be fully exploited. Secondly, we apply the theory of local structure learning to the features of data, so that the similarity of data features is considered. Then we added a low rank constraint to consider the global information of the data. Finally, we add sparse learning to make feature selection. The experimental results show that the proposed algorithm has better results than the comparison methods
RRNet: Relational Reasoning Network with Parallel Multi-scale Attention for Salient Object Detection in Optical Remote Sensing Images
Salient object detection (SOD) for optical remote sensing images (RSIs) aims
at locating and extracting visually distinctive objects/regions from the
optical RSIs. Despite some saliency models were proposed to solve the intrinsic
problem of optical RSIs (such as complex background and scale-variant objects),
the accuracy and completeness are still unsatisfactory. To this end, we propose
a relational reasoning network with parallel multi-scale attention for SOD in
optical RSIs in this paper. The relational reasoning module that integrates the
spatial and the channel dimensions is designed to infer the semantic
relationship by utilizing high-level encoder features, thereby promoting the
generation of more complete detection results. The parallel multi-scale
attention module is proposed to effectively restore the detail information and
address the scale variation of salient objects by using the low-level features
refined by multi-scale attention. Extensive experiments on two datasets
demonstrate that our proposed RRNet outperforms the existing state-of-the-art
SOD competitors both qualitatively and quantitatively.Comment: 11 pages, 9 figures, Accepted by IEEE Transactions on Geoscience and
Remote Sensing 2021, project: https://rmcong.github.io/proj_RRNet.htm
Sparse Nonlinear Feature Selection Algorithm via Local Structure Learning
In this paper, we propose a new unsupervised feature selection algorithm by considering the nonlinear and similarity relationships within the data. To achieve this, we apply the kernel method and local structure learning to consider the nonlinear relationship between features and the local similarity between features. Specifically, we use a kernel function to map each feature of the data into the kernel space. In the high-dimensional kernel space, different features correspond to different weights, and zero weights are unimportant features (e.g. redundant features). Furthermore, we consider the similarity between features through local structure learning, and propose an effective optimization method to solve it. The experimental results show that the proposed algorithm achieves better performance than the comparison algorithm
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