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Research on Robust Measurement Method of Heart Rate Using Remote Photoplethysmography Based on Adversarial Learning Network with High and Low Frequency Features

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IEEE Transactions on Circuits and systems for Video Technology 2025年

作者： Zhai, Dezhao Chen, Wei Ding, Yinghao Yu, Ming Li, Qinwei Wu, Hang Tianjin University of Technology Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin300384 China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of Technology China People's Liberation Army Systems Engineering Institute Academy of Military Sciences Tianjin300161 China Civil Aviation University of China Tianjin Key Laboratory for Advanced Signal Processing Tianjin300300 China Nankai University School of Artificial Intelligence Tianjin300381 China

Remote Photoplethysmography (rPPG) is a non-contact method for measuring heart rate (HR) through facial video, breaking the constraints of contact measurements and offering broad application prospects. However, in real monitoring scenarios, the distance of subjects and facial illumination often vary. This leads to degradation of rPPG signals due to changes in facial resolution and light intensity. This paper presents the High and Low Frequency Feature Adversarial Learning Network (HLFF-AL), which utilizes feature space interpolation and composite feature capture to perform multi-band global and local signal extraction. By adopting an adversarial learning strategy, it enhances the capability to capture semantic information of rPPG under varying resolutions and lighting, bridging the differences in rPPG signal generation due to resolution changes. While maintaining accuracy in HR measuring, the robustness of the network is improved to achieve robust measurement of HR via rPPG. Even under high-resolution conditions, the Mean Absolute Error (MAE) for the three public datasets - unchanging lighting (COHFACE, UBFC-rPPG) and varying lighting (BUAA-MIHR) - reached 1.10 bpm, 1.64 bpm, and 4.41 bpm, respectively, with a mere 0.29 bpm difference in MAE between high and low resolutions on the BUAA-MIHR dataset. This demonstrates that HLFF-AL can predict more robust rPPG signals in various resolutions and lighting scenarios, achieving competitive results compared to state-of-the-art methods. © 1991-2012 IEEE.

关键词： Heart

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Flow control for a Two-Stage Proportional Valve with Hydraulic Position Feedback

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Chinese Journal of Mechanical Engineering 2020年第6期33卷 64-76页

作者： He Wang Xiaohu Wang Jiahai Huang Long Quan Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of EducationTaiyuan University of TechnologyTaiyuan030024China Shanxi Transportation Technology Research&Development Co. LtdTaiyuan030024China

The current research mainly focuses on the flow control for the two-stage proportional valve with hydraulic position feedback which is named as Valvistor ***,the Valvistor valve is a proportional throttle valve and the flow fluctuates with the change of load *** flow fluctuation severely restricts the application of the Valvistor *** this paper,a novel flow control method the Valvistor valve is provided to suppress the flow fluctuation and develop a high performance proportional flow *** mathematical model of this valve is established and *** proportional-integral-derivative(PID)controller is adopted in the closed-loop flow control *** feedback is obtained by the flow inference with back-propagation neural network(BPNN)based on the spool displacement in the pilot stage and the pressure differential across the main *** results show that inference with BPNN can obtain the flow data fast and *** the flow control method,the flow can keep at the set point when the pressure differential across the main orifice *** flow control method is effective and the Valvistor valve changes from proportional throttle valve to proportional flow *** the developed proportional flow valve,the settling time of the flow is very short when the load pressure changes *** performances of hysteresis,linearity and bandwidth are in a high *** linear mathematical model can be verified and the assumptions in the system modeling is reasonable.

关键词： Flow control Proportional valve Hydraulic position feedback Back-propagation neural network

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Cu/Ag composite nanotrough embedded polyacrylonitrile film: Transparent conducting electrodes with excellent flexibility and a high quality factor

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Organic Electronics 2025年 144卷

作者： Qinjun Sun Jian Zhao Hua Ding Xiaoqian Wang Qianwen Hu LiYan Gao Yuying Hao College of Physics and Optoelectronics Shanxi Key Laboratory of Photovoltaic Technology and Application Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan 030024 China Graduate School Shanxi Key Laboratory of Photovoltaic Technology Taiyuan University of Technology Taiyuan 030024 China

With high flexibility, conductivity and transparency, metal nanotroughs (NTRs) are considered to be the most promising candidates for flexibility transparent electrode. Here, we report metal NTR films fabricated by electro-spun and thermal evaporation. By optimizing steam treatment time, copper-silver ratio, coverage rate, and transfer process, smooth and continuous metal NTR films were obtained. The Cu/Ag NTR-polyacrylonitrile (PAN) film displayed superior photoelectric properties: transmitted 94.4 % of visible light (550 nm), showed a low sheet resistance of 2.48 Ω/□ and a very high quality factor of 2.27 × 10 −1 (Ω/□) −1 . Meanwhile, the relative change rate of resistance was less than 0.002 under a bending radius of 5 mm after 10,000 cycles. The results indicate that composite metal nanotroughs provide a new way for the preparation of high performance flexible transparent electrode.

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Non-reciprocity of energy transfer derived from cubic stiffness-induced nonlinear phenomena

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Results in Physics 2025年 73卷

作者： Kong, Na Sun, Min Chen, Jianen Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin 300384 China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of Technology Tianjin 300384 China School of Science Tianjin Chengjian University Tianjin 300384 China

Introducing purely nonlinear elastic elements can induce rich dynamic behaviors, such as bifurcations, jumps and isolated resonance curves, to linear systems. Therefore, these elements are suitable for constructing strong non-reciprocity of vibration energy transfer. First, the energy transfer along reciprocal directions in a three-degree-of-freedom system is investigated, where three oscillators are connected by cubic springs. The semi-analytical solutions of the system are obtained using the complexification-averaging method and the least squares method. The results are compared against numerical solutions obtained by the Runge-Kutta method. The excitation amplitude range that produces strong non-reciprocity of vibration energy is analyzed. The jump phenomenon under combined excitation is investigated, and a trigger method for constructing non-reciprocity using an impulse is proposed. Then, an oscillator chain with cubic stiffness and scaling parameters is embedded into a multi-degree-of-freedom linear oscillator system to further explore the effect of cubic stiffness. Energy transfer along two directions is compared by exciting the leftmost oscillator and the rightmost oscillator. Moreover, the trigger effect of the impulse on non-reciprocity is demonstrated. The results show significant differences in vibration energy transfer within three distinct frequency bands. The critical points between reciprocal and non-reciprocal states are obtained, and the three stages of reciprocity related to excitation amplitude are analyzed. Lastly, the modulation effect of the cubic stiffness on non-reciprocity is conducted by comparing the energy of the output oscillator. © 2025 The Authors

关键词： Cubic stiffness Energy transfer Jump phenomenon Non-reciprocity

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Chaos generation by a hybrid integrated chaotic semiconductor laser

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Chinese Physics B 2018年第5期27卷 122-130页

作者： Ming-Jiang Zhang Ya-Nan Niu Tong Zhao Jian-Zhong Zhang Yi Liu Yu-Hang Xu Jie Meng Yun-Cai Wang An-Bang Wang Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of TechnologyTaiyuan 030024China Institute of Optoelectronic Engineering College of Physics&OptoelectronicsTaiyuan University of TechnologyTaiyuan 030024China

We design a hybrid integrated chaotic semiconductor laser with short-cavity optical *** can be assembled in a commercial butterfly shell with just three *** of them is coated by a transflective film to provide the optical feedback for chaos generation while insuring regular laser *** prove the feasibility of the chaos generation in this compact structure and provide critical external parameters for the fabrication by theoretical *** than the usual changeless internal parameters used in previous simulation research,we extract the real parameters of the chip by ***,the maps of the largest Lyapunov exponent with varying bias current and feedback intensity Kap demonstrate the dynamic characteristics under different external-cavity *** laser chip has its own optimal external cavity length(L)and feedback intensity(Kap)to generate chaos because of the different internal *** have acquired two ranges of optimal parameters(L=4 mm,0.12〈Kap〈0.2 and L=5 mm,0.07〈Kap〈0.12)for two different chips.

关键词： chaotic dynamic characteristics integrated chaotic semiconductor laser short-cavity optical feedback extraction of internal parameters

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controllable optical bistability in a three-mode optomechanical system with a membrane resonator

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Chinese Physics B 2018年第7期27卷 382-387页

作者： Jiakai Yan Xiaofei Zhu Bin Chen Department of Physics College of Physics and OptoelectronicsTaiyuan University of TechnologyTaiyuan 030024Chin Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan 030024China

We study the optical bistability （OB） in a three-mode cavity optomechanical system, where an oscillating membrane of perfect reflection is inserted between two fixed mirrors of partial transmission. By investigating the behavior of steady state solutions, we find that the left and right cavities will exhibit the bistable behavior simultaneously in this optomechanical system by adjusting the left and right coupling fields. In addition, one can control the OB threshold and the width of the OB curve via adjusting the coupling strength, the detuning, and the decay rate. Moreover, we further illustrate the OB appearing in the cavity by the effective potential as a function of the position.

关键词： optical bistability oscillating membrane optomechanical system

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High-performance chiral all-optical OR logic gate based on topological edge states of valley photonic crystal

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Chinese Physics B 2023年第7期32卷 392-398页

作者：王晓蓉费宏明林瀚武敏康丽娟张明达刘欣杨毅彪肖连团 College of Physics Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China School of Science RMIT UniversityMelbourneVictoria 3000Australia

For all-optical communication and information processing,it is necessary to develop all-optical logic gates based on photonic structures that can directly perform logic ***-optical logic gates have been demonstrated based on conventional waveguides and interferometry,as well as photonic crystal ***,any defects in those structures will introduce high scattering loss,which compromises the fidelity and contrast ratio of the information *** on the spin-valley locking effect that can achieve defect-immune unidirectional transmission of topological edge states in valley photonic crystals(VPCs),we propose a high-performance all-optical logic OR gate based on a VPC *** tuning the working bandwidth of the two input channels,we prevent interference between the two channels to achieve a stable and high-fidelity *** transmittance of both channels is higher than 0.8,and a high contrast ratio of 28.8 dB is ***,the chirality of the logic gate originated from the spin-valley locking effect allows using different circularly polarized light as inputs,representing“1”or“0”,which is highly desired in quantum *** device’s footprint is 18μm×12μm,allowing high-density on-chip *** addition,this design can be experimentally fabricated using current nanofabrication techniques and will have potential applications in optical communication,information processing,and quantum computing.

关键词： topological photonics topological edge state valley photonic crystal all-optical logic gate

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Bearing Fault Diagnosis with DDCNN Based on intelligent Feature Fusion Strategy in Strong Noise

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Computers, Materials & Continua 2023年第12期77卷 3423-3442页

作者： Chaoqian He Runfang Hao Kun Yang Zhongyun Yuan Shengbo Sang Xiaorui Wang College of Electronic Information and Optical Engineering Taiyuan University of TechnologyTaiyuan030024China Key Lab of Advanced Transducers and Intelligent Control System of the Ministry of Education Taiyuan030024China

intelligent fault diagnosis in modern mechanical equipment maintenance is increasingly adopting deep learning ***,conventional bearing fault diagnosis models often suffer from low accuracy and unstable performance in noisy environments due to their reliance on a single input ***,this paper proposes a dual-channel convolutional neural network(DDCNN)model that leverages dual data *** DDCNN model introduces two key ***,one of the channels substitutes its convolution with a larger kernel,simplifying the structure while addressing the lack of global information and shallow ***,the feature layer combines data from different sensors based on their primary and secondary importance,extracting details through small kernel convolution for primary data and obtaining global information through large kernel convolution for secondary *** experiments conducted on two-bearing fault datasets demonstrate the superiority of the two-channel convolution model,exhibiting high accuracy and robustness even in strong noise ***,it achieved an impressive 98.84%accuracy at a Signal to Noise Ratio(SNR)of−4 dB,outperforming other advanced convolutional models.

关键词： Fault diagnosis dual-data dual-channel feature fusion noise-resistance

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An automated pulmonary parenchyma segmentation method based on an improved region growing algorithm in PET-CT imaging

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Frontiers of Computer Science 2016年第1期10卷 189-200页

作者： Juanjuan ZHAO Guohua JI Xiaohong HAN Yan QIANG Xiaolei LIAO College of Computer Science and Technology Taiyuan University of Technology Taiyuan 030024 China Key Laboratory of Advanced Transducers and Intelligent Control Systems Taiyuan University of Technology Taiyuan 030024 China

To address the incomplete problem in pulmonary parenchyma segmentation based on the traditional methods, a novel automated segmentation method based on an eight- neighbor region growing algorithm with left-right scanning and four-corner rotating and scanning is proposed in this pa- per. The proposed method consists of four main stages： image binarization, rough segmentation of lung, image denoising and lung contour refining. First, the binarization of images is done and the regions of interest are extracted. After that, the rough segmentation of lung is performed through a general region growing method. Then the improved eight-neighbor region growing is used to remove noise for the upper, mid- dle, and bottom region of lung. Finally, corrosion and ex- pansion operations are utilized to smooth the lung boundary. The proposed method was validated on chest positron emis- sion tomography-computed tomography （PET-CT） data of 30 cases from a hospital in Shanxi, China. Experimental results show that our method can achieve an average volume overlap ratio of 96.21 ± 0.39% with the manual segmentation results. Compared with the existing methods, the proposed algorithm segments the lung in PET-CT images more efficiently and ac- curately.

关键词： pulmonary parenchyma segmentation bot-tom region of lung image binarization iterative threshold seeded region growing four-corner rotating and scanning,denoising contour refining PET-CT

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Absorption enhancement in organic solar cells based on the plasmonic hot spot effect

Absorption enhancement in organic solar cells based on the p...

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Asia Communications and Photonics Conference, ACP 2013

作者： Zhang, Ye Wang, Wenyan Cui, Yanxia Li, Zhanfeng Ji, Ting Hao, Yuying Key Laboratory of Advanced Transducers and Intelligent Control System College of Physics and Optoelectronics Taiyuan University of Technology Taiyuan 030024 China

By introducing metallic nanostrips in organic solar cells with the excitation of the plasmonic hot spot effect, we improve light absorption in active layer by 24 % in comparison with the corresponding planar device. &... 详细信息

ISBN: (纸本)9781557529893

关键词： Organic solar cells

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