Publications by authors named "Pengwen Xiong"

Article Synopsis
  • This study addresses the issue of subjective and resource-heavy methods in classroom quality analysis by proposing a computer vision-based solution that utilizes Dense 3D Convolutional Residual Networks (D3DCNN_ResNet) for recognizing student expressions and behaviors in English classrooms.
  • The D3DCNN_ResNet combines target detection via Single Shot Multibox Detector (SSD) with advanced 3D convolution techniques, successfully tested on the CK+ dataset for expressions and the KTH dataset for behaviors.
  • The results indicate exceptional performance, achieving 97.94% accuracy for expression recognition and 98.86% for behavior recognition, suggesting the model's potential to enhance educational strategies by offering real-time feedback on student engagement.
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. Overcomplete dictionaries are widely used in compressed sensing (CS) to improve the quality of signal reconstruction. However, dictionary learning under theℓ0-norm orℓ1-norm constraint inevitably produces dictionary atoms that are negatively correlated with the original signal; meanwhile, when we use a sparse linear combination of dictionary atoms to represent a signal, it is suboptimal for the dictionary atoms to "cancel each other out" by addition and subtraction to approximate the sample.

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This work proposes a scalable gamma non-negative matrix network (SGNMN), which uses a Poisson randomized Gamma factor analysis to obtain the neurons of the first layer of a network. These neurons obey Gamma distribution whose shape parameter infers the neurons of the next layer of the network and their related weights. Upsampling the connection weights follows a Dirichlet distribution.

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Early warning on the ship deficiency is crucial for enhancing maritime safety, improving maritime traffic efficiency, reducing ship fuel consumption, etc. Previous studies focused on the ship deficiency exploration by mining the relationships between the ship physical deficiencies and the port state control (PSC) inspection results with statistical models. Less attention was paid to discovering the correlation rules among various parent ship deficiencies and subcategories.

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Maritime surveillance videos provide crucial on-spot kinematic traffic information (traffic volume, ship speeds, headings, etc.) for varied traffic participants (maritime regulation departments, ship crew, ship owners, etc.) which greatly benefits automated maritime situational awareness and maritime safety improvement.

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Herein, the problem of target tracking in wireless sensor networks (WSNs) is investigated in the presence of Byzantine attacks. More specifically, we analyze the impact of Byzantine attacks on the performance of a tracking system. First, under the condition of jointly estimating the target state and the attack parameters, the posterior Cramer-Rao lower bound (PCRLB) is calculated.

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In order to improve the precision and stability of puncture surgical operations to assist doctors in completing fine manipulation, a new of type puncturing needle sensor is proposed based on a fiber Bragg grating (FBG). Compared with the traditional puncture needle sensor, the new type of puncturing needle sensor is able to sense not only the axial force, but also the torque force during the puncture process. A spoke-type structure is designed near the needle tip.

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