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Gamma oscillations and their role in orchestrating balance and communication following stroke

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Neural Regeneration Research 2025年第2期20卷 477-478页

作者： Montana Samantzis Cong Wang Matilde Balbi Queensland Brain Institute The University of QueenslandBrisbaneQLDAustralia Engineering Research Centre of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghaiChina

Induced brain oscillations in the gamma range have recently garnered attention due to their reported neuroprotective effects in the treatment of Alzheimer’s *** method differs from pharmacological approaches by tapping into the neuronal population dynamics that underlie the homeostatic processes in the brain that are crucial for the recovery of ***,induced gamma-range oscillations have been used to improve cerebral blood flow,motor function,and synaptic plasticity in a mouse model of focal stroke,highlighting the broad potential of recruiting intrinsic recovery processes for the treatment of neurological *** open questions,such as the frequency specificity of the benefits,will shed light on the intrinsic processes involved and allow clinicians to optimize recovery after stroke.

关键词： protective specificity Alzheimer

Diffusion Based Molecular communication:Principle,Key Technologies,and Challenges

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China communications 2017年第2期14卷 1-18页

作者： Jiaxing Wang Bonan Yin Mugen Peng Key Laboratory of Universal Wireless communication Ministry of Education Beijing University of Posts and TelecommunicationsBeijing 100876 China

Molecular communication(MC) is a kind of communication technology based on biochemical molecules for internet of bio-nano things, in which the biochemical molecule is used as the information carrier for the interconnection of nano-devices. In this paper, the basic principle of diffusion based MC and the corresponding key technologies are comprehensively surveyed. In particular, the state-ofthe-art achievements relative to the diffusion based MC are discussed and compared, including the system model, the system performance analysis with key influencing factors, the information coding and modulation techniques. Meanwhile, the multi-hop nano-network based on the diffusion MC is presented as well. Additionally, given the extensiveness of the research area, open issues and challenges are presented to spur future investigations, in which the involvement of channel model, information theory, self-organizing nano-network, and biochemical applications are put forward.

关键词： molecular communication diffusion nano-networks information molecule

Effects of the Lithologic Character of Manufactured Sand on Properties of Concrete

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Journal of Wuhan University of Technology(Materials Science) 2014年第6期29卷 1213-1218页

作者：王稷良 YANG Zhifeng LIU Yihan Research Institute of Highway ministry of communication

Six representative parent rocks of sand, including limestone, quartzite, gneisses, granite, Basalt and Marble were selected to conduct a systematical research on the effects of various lithologies of manufactured sand on the workability, mechanism properties, volume stability and durability of manufacturedsand concrete. The experimental results show that the strength of manufactured-sand concrete is slightly higher than that of natural-sand concrete. Furthermore, substituting 15% cement of the concrete mixture with equal quantity of the six different lithology stone powder respectively, the data indicated that they can improve the concrete’s workability, postpone the plastic cracking time, enhance the anti-cracking grade, and have no obvious effect on the properties of antifreeze and sulfate attack resistance but reduce the capability to resist chloride ion penetration. Moreover, the differences in concrete’s workability, mechanism properties, volume stability and durability caused by various lithologies of manufactured sand and stone powder were not significant and the influence of lithology variety on the macro properties of concrete could be neglected eventually.

关键词： manufactured sand lithologic character workability volume stability durability

Pilot-Free End-to-End Underwater Acoustic communication System Based on Autoencoder

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Journal of communications and Information Networks 2024年第3期9卷 233-243页

作者： Yizhe Wang Deqing Wang Liqun Fu School of Informatics and Key Laboratory of Underwater Acoustic Communication and Marine Information Technology of Ministry of EducationXiamen UniversityXiamen 361005China

The long delay spreads and significant Doppler effects of underwater acoustic(UWA)channels make the design of the UWA communication system more *** this paper,we propose a learning-based end-to-end framework for UWA communications,leveraging a double feature extraction network(DFEN)for data *** DFEN consists of an attentionbased module and a mixer-based module for channel feature extraction and data feature extraction,*** the diverse nature of UWA channels,we propose a stack-network with a two-step training strategy to enhance *** avoiding the use of pilot information,the proposed network can learn data mapping that is robust to UWA *** results show that our proposed algorithm outperforms the baselines by at least 2 dB under bit error rate(BER)10^(−2)on the simulation channel,and surpasses the compared neural network by at least 5 dB under BER 5×10^(−2)on the experiment channels.

关键词： underwater acoustic communications autoencoder time-varying channel

Joint Optimization of Resource Allocation and Trajectory Based on User Trajectory for UAV-Assisted Backscatter communication System

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China communications 2024年第2期21卷 197-209页

作者： Peizhong Xie Junjie Jiang Ting Li Yin Lu School of communication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing 210003China

The Backscatter communication has gained widespread attention from academia and industry in recent years. In this paper, A method of resource allocation and trajectory optimization is proposed for UAV-assisted backscatter communication based on user trajectory. This paper will establish an optimization problem of jointly optimizing the UAV trajectories, UAV transmission power and BD scheduling based on the large-scale channel state signals estimated in advance of the known user trajectories, taking into account the constraints of BD data and working energy consumption, to maximize the energy efficiency of the system. The problem is a non-convex optimization problem in fractional form, and there is nonlinear coupling between optimization *** iterative algorithm is proposed based on Dinkelbach algorithm, block coordinate descent method and continuous convex optimization technology. First, the objective function is converted into a non-fractional programming problem based on Dinkelbach method,and then the block coordinate descent method is used to decompose the original complex problem into three independent sub-problems. Finally, the successive convex approximation method is used to solve the trajectory optimization sub-problem. The simulation results show that the proposed scheme and algorithm have obvious energy efficiency gains compared with the comparison scheme.

关键词： energy efficiency joint optimization UAV-assisted backscatter communication user trajectory

Fractional Fourier domain hopped communication method based on chirp modulation for underwater acoustic channels

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Journal of Systems Engineering and Electronics 2017年第3期28卷 449-456页

作者： Xingbin Tu Xiaomei Xu Zheguang Zou Liangliang Yang Jianming Wu College of Ocean and Earth Science Xiamen UniversityXiamen 361102China Key Laboratory of Underwater Acoustic communication and Marine Information Technology Ministry of EducationXiamen 361005China

To improve the data rate of underwater acoustic frequency-hopped communications, frequency hopping is applied to different orders of fractional Fourier domain (FrFD), to enable non-intrusive, bandwidth-limited acoustic communications. An FrFD frequency-hopped communication method based on chirp modulation, namely multiple chirp shift keying-FrFD hopping (MCSK-FrFDH), is proposed for underwater acoustic channels. Validated by both simulations and experimental results, this method can reach a bandwidth efficiency twice more than conventional frequency-hopped methods with the same data rate and anti-multipath capability, suggesting that the proposed method achieves a better performance than the traditional frequency hopped communication in underwater acoustic communication channels. Results also show that in practical scenarios, the MCSK-FrFDH system with longer symbol length performs better at the low signal-to-noise ratio (SNR), while the system with larger frequency sweeping range performs better at a high SNR.

关键词： underwater acoustic communication fractional Fourier domain (FrFD) frequency hopping chirp signal

Actively mode-locked fiber ring laser based on photonic crystal fiber

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Chinese Optics Letters 2006年第6期4卷 342-344页

作者：何理杨伯君宋学鹏张晓光于丽 Key Laboratory of Optical communication and Lightwave Technologies ministry of Education Key Laboratory of Optical communication and Lightwave Technologies ministry of Education

A wavelength tunable, high repetition rate mode-locked fiber ring laser was demonstrated. In the experiment, photonic crystal fiber （PCF） is used as an intracavity compression medium. The high nonlinearity and anomalous dispersion of PCF can cause intracavity compression and result in significant reduction in the pulse width. The pulses duration at the repetition rate of 9.99 GHz was less than 10 ps over the range of 1532-1565 nm.

关键词： Crystals Dispersions Fiber lasers Laser mode locking Laser pulses

Task-Oriented Semantic communication with Foundation Models

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China communications 2024年第7期21卷 65-77页

作者： Chen Mingkai Liu Minghao Zhang Zhe Xu Zhiping Wang Lei Key Laboratory of Broadband Wireless communication and Sensor Network Technology Ministry of EducationNanjing University of Posts and TelecommunicationsNanjing 210003China School of Ocean Information Engineering Jimei UniversityXiamen 361021China Key Laboratory of Underwater Acoustic communication and Marine Information Technology(Xiamen University) Ministry EducationXiamen 361005China

In the future development direction of the sixth generation(6G)mobile communication,several communication models are proposed to face the growing challenges of the *** rapid development of artificial intelligence(AI)foundation models provides significant support for efficient and intelligent communication *** this paper,we propose an innovative semantic communication paradigm called task-oriented semantic communication system with foundation ***,we segment the image by using task prompts based on the segment anything model(SAM)and contrastive language-image pretraining(CLIP).Meanwhile,we adopt Bezier curve to enhance the mask to improve the segmentation ***,we have differentiated semantic compression and transmission approaches for segmented ***,we fuse different semantic information based on the conditional diffusion model to generate high-quality images that satisfy the users'specific task ***,the experimental results show that the proposed system compresses the semantic information effectively and improves the robustness of semantic communication.

关键词： diffusion model foundation model joint source-channel coding task-oriented semantic communication

Guaranteeing Wireless communication Reliability via an Extended Hybrid Carrier System

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China communications 2023年第7期20卷 192-202页

作者： Ge Song Xiaojie Fang Xuejun Sha School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China Engineering Research Center for Dedicated communication System Ministry of EducationHarbin 150080China

In this paper,we propose an extended hybrid carrier system based on the weighted fractional Fourier transform to ensure the reliability of wireless *** proposed scheme improves the dispersion and compensation capabilities of the hybrid carrier system for channel fading through the design of the signal power distribution,which has greatly reduced the probability of high-power distortion of the signal and improved the bit error rate performance as a *** analysis has shown the superiority of the extended hybrid carrier *** a lower cost of computational complexity increment,the proposed scheme obtains a performance improvement without occupying additional time-frequency physical *** with the existing hybrid carrier scheme,numerical simulation results have shown that the proposed extended hybrid carrier scheme has better anti-fading performance under the doubly-selective channel and improves the reliability of the wireless communication system effectively.

关键词： extended hybrid carrier weighted frac-tional Fourier transform bit error rate doubly-selective channel