Time-varying channel estimation in reconfigurable intelligent surface assisted communication system by Kai SHAO, Ben LU, Guangyu WANG

“…Aiming at the key problems need to be solved, such as cascade channel sparse representation, time-varying channel parameter tracking and signal reconstruction, for time-varying cascade channels estimation of reconfigurable intelligent surface (RIS) assisted communication system, a Khatri-Rao and hierarchical Bayesian Kalman filter (KR-HBKF) algorithm was proposed.Firstly, the Khatri-Rao product and Kronecker product transformations were used to obtain the sparse representation of RIS cascaded channels based on the sparse characteristics of channels, thus the RIS cascaded channel estimation problem was transformed into a low-dimensional sparse signal recovery problem.Then, according to the state evolution model of RIS cascaded channel, the time correlation parameter was introduced into the prediction model of HBKF algorithm, and the improved HBKF was applied to solve the problem of time-varying channel parameter tracking and signal reconstruction for completing the time-varying cascaded channels estimation.The sparsity and time correlation of the channel were comprehensively considered in the KR-HBKF algorithm, thus better estimation accuracy could be obtained with small pilot overhead.Compared with the traditional compressed sensing algorithm, the simulation results show that the proposed algorithm has about 5 dB estimated performance improvement, and better robustness performance under different time-varying channel conditions.…”
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Presynaptic Ionotropic Receptors Controlling and Modulating the Rules for Spike Timing-Dependent Plasticity by Matthijs B. Verhoog, Huibert D. Mansvelder

“…Furthermore, we will discuss how interaction between different types of ionotropic receptors may create “timing” windows during which particular timing rules lead to synaptic changes.…”
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Impact of Microwave Time on the Structure and Functional Properties of Glycosylated Soy 7S Globulins by Jixin Zhang, Tao Cui, Lan Zhang, Huiqing Xu, Jingguo Xu, Jun Wang

“…This study explores the mechanism of how microwave processing time affects the structure and functional properties of glycosylated soybean 7S protein and identifies 60 s as the optimal microwave processing time. …”
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A real-time detection method for multi-scale ships in complex scenes by Weina ZHOU, Lu LIU

“…Ship detection plays an important role in tasks such as military reconnaissance, maritime target tracking, and maritime traffic control.However, due to the influence of variable sizes of ships and complex background of sea surface, detecting multi-scale ships remains a challenge in complex sea surfaces.To solve this problem, an improved YOLOv4 method based on multi-layers information interactive fusion and attention mechanism was proposed.Multi-layers information interactive fusion (MLIF) and multi-attention receptive field (MARF) were applied and combined reasonably to build a bidirectional fine-grained feature pyramid.MLIF was used to fuse feature of different scales, which not only concatenated high-level semantic features from deep layers, but also reshaped richer features from shallower layers.MARF consisted of receptive field block (RFB) and attention mechanism module, which effectively emphasized the important features and suppressed unnecessary ones.In addition, to further evaluate the performance of the proposed method, experiments were carried out on Singapore maritime dataset (SMD).The results illustrate that the method proposed can effectively solve the problem of difficult detection of multi-scale ships in complex marine environment, and meet the real-time requirements at the same time.…”
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Reconstruction in time-warped weighted shift-invariant spaces with application to spline subspaces by Jun Xian, Yongjin Li

“…In the spline subspace, we give a reconstruction formula in a time-warped spline subspace.…”
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Becoming a leader in psychiatry and mental health: now is the time to step forward by Juan Oms, Roberto Martinez Caballero, Jorge Betancourt, Marcos A. Sanchez-Gonzalez

“…This review explores the barriers to integrating leadership into psychiatric education, including limited time and resources, the absence of formal leadership curricula, and the undervaluation of leadership skills within medical training.Evidence from existing leadership development programs demonstrates the positive impact of leadership education on reducing burnout and enhancing empathy among medical professionals. …”
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A Time Modulated Printed Dipole Antenna Array for Beam Steering Application by Ruchi Gahley, Banani Basu

“…This paper presents time modulated beam steered antenna array without phase shifters. …”
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An Efficient Alternating Segment Parallel Difference Method for the Time Fractional Telegraph Equation by Lifei Wu, Xiaozhong Yang

“…This implies that the parallel difference schemes are efficient for solving the time fractional telegraph equation.…”
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Numerical investigation of singularly perturbed time lag parabolic differential-difference equations by Imiru Takele Daba, Wondwosen Gebeyaw Melesse, Fasika Wondimu Gelu, Guta Demisu Kebede

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Real-Time Classification of Deep and Non-Deep Sleep With Comparative Intervention Experiments by Mo Xia, Hongxi Xue, Boning Li, Jianting Cao

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Analytical Threshold for Chaos of Piecewise Duffing Oscillator with Time-Delayed Displacement Feedback by Zhang Ming-Xin, Wang Jun, Shen Yong-Jun, Zhang Jian-Chao

“…The effects of excitation frequency and time delay of the displacement feedback are analytically discussed. …”
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Time Domain Response of Uniform RC Lines with RC Termination at Both Ends by Muhammad Taher Abuelma'atti

“…The time domain response of uniform RC lines with RC termination at both ends is obtained from the approximate poles of the transfer function. …”
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Factors Leading to a Lack of Leisure Time in High School Students in Croatia by Martina Lončar, Luka Pongračić, Aleksandra Tonković

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Coherent Signal DOA Estimation Method Based on Space–Time–Coding Metasurface by Guanchao Chen, Xiaolong Su, Lida He, Dongfang Guan, Zhen Liu

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Missed Lung Cancers on the Scout View: Do We Look Every Time? by Sarfraz Ahmed Nazir, Rachel Benamore, Fergus Gleeson

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Autobiographical Memory Retrieval and Hippocampal Activation as a Function of Repetition and the Passage of Time by Lynn Nadel, Jenna Campbell, Lee Ryan

“…We tested this hypothesis utilizing fMRI, comparing the effect of memory retrieval versus the mere passage of time on hippocampal activation. While undergoing fMRI scanning, participants retrieved remote autobiographical memories that had been previously retrieved either one month earlier, two days earlier, or multiple times during the preceding month. …”
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Filter Realization of the Time-Domain Average Denoising Method for a Mechanical Signal by Wuwei Feng, Cuizhu Wang, Xin Chen, Yuzhou Shi, Meng Jiang, Di Wang

“…Time-domain averaging (TDA) is an effective signal processing technique in fault diagnosis that can extract the periodic components of interest from signals mixed with noise interference while suppressing other irrelevant periodic signals. …”
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Exponential Convergence for Cellular Neural Networks with Time-Varying Delays in the Leakage Terms by Zhibin Chen, Junxia Meng

“…We consider a class of cellular neural networks with time-varying delays in the leakage terms. By applying Lyapunov functional method and differential inequality techniques, we establish new results to ensure that all solutions of the networks converge exponentially to zero point.…”
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Research of production technology as a factor influencing the time of the product assembly cycle by V. S. Ponomareva, O. V. Khomutskaya

“…Nowadays the organization of domestic serial production of high-tech products requires a lot of time. On the one hand, the reason is the restructuring of logistics chains with foreign suppliers, on the other hand, the building of cooperation in the country. …”
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Anti-Unwinding Attitude Control with Fixed-Time Convergence for a Flexible Spacecraft by Chutiphon Pukdeboon, Anuchit Jitpattanakul

“…This paper investigates the fixed-time attitude tracking control problem for flexible spacecraft with unknown bounded disturbances. …”
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