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Dynamic terahertz multi-channel beam steering with dual-frequency multiplexing based on magneto-optical metasurfaces
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作者 Dan Zhao Fei Fan +5 位作者 Hao Wang Pengxuan Li Zhen Xu Jining Li Yunyun Ji Shengjiang Chang 《Advanced Photonics Nexus》 2025年第3期149-157,共9页
With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A mag... With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A magnetic phase-coding meta-atom(MPM)is formed by the heterogeneous integration of La:YIG magneto-optical(MO)materials and Si microstructures.The MPM couples the magnetic induction phase of spin states with the propagation phase and can simultaneously satisfy the required output phase for dual frequencies under various external magnetic fields to realize the dynamic beam steering among multiple channels at 0.25 and 0.5 THz.The energy ratio of the target direction can reach 96.5%,and the nonreciprocal one-way transmission with a max isolation of 29.8 dB is realized due to the nonreciprocal phase shift of the MO layer.This nonreciprocal mechanism of magnetic induction reshaping of wavefront significantly holds promise for advancing integrated multi-functional THz devices with the characteristics of low-crosstalk,multi-channel,and multi-frequency,and has great potential to promote the development of THz large-capacity and high-speed communication. 展开更多
关键词 TERAHERTZ multi-channel DUAL-FREQUENCY nonreciprocal transmission beam steering dynamics
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Terahertz active multi-channel vortices with parity symmetry breaking and near/far field multiplexing based on a dielectric-liquid crystal-plasmonic metadevice
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作者 Yiming Wang Fei Fan +3 位作者 Huijun Zhao Yunyun Ji Jing Liu Shengjiang Chang 《Opto-Electronic Advances》 2025年第5期48-58,共11页
Vortex beams carrying orbital angular momentum(OAM)are of great significance for high-capacity communication and super-resolution imaging.However,there is a huge gap between the free-space vortices(FVs)and plasmonic v... Vortex beams carrying orbital angular momentum(OAM)are of great significance for high-capacity communication and super-resolution imaging.However,there is a huge gap between the free-space vortices(FVs)and plasmonic vortices(PVs)on chips,and active manipulation as well as multiplexing in more channels have become a pressing demand.In this work,we demonstrate a terahertz(THz)cascaded metadevice composed of a helical plasmonic metasurface,a liquid crystal(LC)layer,and a helical dielectric metasurface.By spin-orbital angular momentum coupling and photon state superposition,PVs and FVs are generated with mode purity of over 85%on average.Due to the inversion asymmetric design of the helical metasurfaces,the parity symmetry breaking of OAM is realized(the topological charge numbers no longer occur in positive and negative pairs,but all are positive),generating 6 independent channels associated with the decoupled spin states and the near-/far-field positions.Moreover,by the LC integration,dynamic mode switching and energy distribution can be realized,finally obtaining up to 12 modes with a modulation ratio of above 70%.This active tuning and multi-channel multiplexing metadevice establishes a bridge connection between the PVs and FVs,exhibiting promising applications in THz communication,intelligent perception,and information processing. 展开更多
关键词 TERAHERTZ optical vortex plasmonic metasurface near/far field multi-channel liquid crystal
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Multi-Channel Electrolyte Supply for Electrochemical Trepanning of Blisks Using Rotational Feeding Combined with Shift Feeding
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作者 Gaopan Lei Dong Zhu +3 位作者 Mingzhu Ren Erhao Jiao Yongquan Xie Mingfu Li 《Chinese Journal of Mechanical Engineering》 2025年第2期440-458,共19页
Rotational feeding combined with shift feeding electrochemical trepanning(RF-SF ECTr)is an effective method for machining aeroengine blisks.However,given the variable relative motion of the electrodes and the complex ... Rotational feeding combined with shift feeding electrochemical trepanning(RF-SF ECTr)is an effective method for machining aeroengine blisks.However,given the variable relative motion of the electrodes and the complex flow channels around the bending and twisting blades,the accessibility and uniformity of the flow field are poor in blisk RF-SF ECTr using the traditional electrolyte supply(TES)mode,resulting in poor machining stability and low machining efficiency.To improve the distribution of the flow field,a new multi-channel electrolyte supply(MCES)mode is proposed for blisk RF-SF ECTr,in which the position and volume of the electrolyte supply are controlled effectively by setting multiple inlet channels in the liquid inlet area.A flow-field simulation comparison between TES and MCES shows that better accessibility and uniformity of the flow-field distribution are achieved under MCES.To clarify further the flow-field distribution characteristics under RF-SF ECTr,a series of flow-field simulations was conducted at different machining depths.Based on the obtained dynamic change law for the flow field,to enhance further its uniformity and accessibility,a global coverage strategy for the electrolyte supply and a flow-field structure optimization method for MCES are proposed,which involve optimizing the number,diameter,and location of the inlet channels.After many simulations,the optimal MCES structure was achieved whereby the electrolyte covers all positions effectively in the processing area.To verify the proposed method as effective and correct,a series of RF-SF ECTr experiments was carried out.Under the optimized MCES mode,the feeding rate was increased from 0.8 mm/min with the TES mode to 2.0 mm/min,and the processing stability and efficiency were improved significantly.The methods presented here offer an effective guide for flow-field optimization when machining other components with complex spatial structures. 展开更多
关键词 Electrochemical trepanning Blisk Rotational feeding Flow field optimization multi-channel electrolyte supply
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Analysis of the effect of multi-channel continuous nursing intervention on patients post-radical gastrectomy
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作者 Huan-Li Luo Huan-Ling Luo 《World Journal of Gastrointestinal Surgery》 2025年第4期110-119,共10页
BACKGROUND Radical gastrectomy(RGE)for gastric carcinoma(GC)has exerted definite therapeutic efficacy in treating patients with GC.However,a notable risk of postoperative complications(POCs)persists among middle-aged ... BACKGROUND Radical gastrectomy(RGE)for gastric carcinoma(GC)has exerted definite therapeutic efficacy in treating patients with GC.However,a notable risk of postoperative complications(POCs)persists among middle-aged and elderly patients with compromised physiological functions.Hence,developing and implementing reliable nursing interventions to optimize the comprehensive management of these patients is deemed imperative.AIM To analyze the association of multi-channel continuous nursing intervention with POCs,negative emotions(NEs),and quality of life(QoL)of patients undergoing RGE for GC.METHODS This retrospective study selected 99 patients who underwent RGE for GC in our hospital from May 2020 to May 2023.Participants were categorized into the control(n=49 cases)and research groups(n=50 cases)receiving routine and multi-channel continuous nursing care,respectively.Comparative analysis involved data on postoperative rehabilitation(time to first anal exhaust,oral feeding and ambulation,and hospital stay),complications(nausea and vomiting,delayed gastric emptying,and abdominal distension),NEs[Self-rating Anxiety(SAS)/Depression Scale(SDS)],treatment compliance,self-efficacy,and QoL[World Health Organization QoL Brief Version(WHOQOL-BREF)].RESULTS Compared to the control group,the research group demonstrated earlier first postoperative anal exhaust,oral feeding,and ambulation,shorter hospital stay,lower POC rate,and more reduced SAS and SDS scores postintervention,which was significantly lower than the baseline.The treatment compliance scores were significantly higher in the research group than in the control group in terms of medication adherence,daily exercise,reasonable diet,and regular review.Further,the research group demonstrated increased self-efficacy scores in terms of positive attitude,self-stress relief,and self-decision-making,as well as the overall score postintervention,which were higher than the control group.Moreover,the research group reported notably higher WHOQOL-BREF scores in domains such as physiology,psychology,social relations,and environment.CONCLUSION Multi-channel continuous nursing intervention prevents POCs in patients undergoing RGE for GC as well as significantly alleviates patients’NEs and boosts their QoL. 展开更多
关键词 Radical gastrectomy multi-channel continuous nursing Postoperative complications Negative emotions Quality of life
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Development of multi-channel observation and inversion for IP electrical sounding method 被引量:8
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作者 刘海飞 柳建新 +3 位作者 郭荣文 童孝忠 龚露 彭艳华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期816-823,共8页
In order to improve the exploration effect of deep non-ferrous mineral resources, multi-channel observation methods for induced polarization (IP) electrical sounding data and their inversion imaging technology are s... In order to improve the exploration effect of deep non-ferrous mineral resources, multi-channel observation methods for induced polarization (IP) electrical sounding data and their inversion imaging technology are studied. First of all, four multi-channel observation methods are developed based on conventional IP electrical method, namely three-electrode and four-electrode arrays of unilateral and bilateral current transmitting. Then the maximum smoothness constrained inversion method of the least squares sense for IP electrical sounding data is proposed, and the inversion software is programmed. Finally, the simulation and inversion results of geo-electrical model for the proposed observation methods are analyzed. And the comparison results show that three-electrode array of bilateral current transmitting gives the best result, but the intensity in field work is larger than others; unilateral three-electrode and four-electrode arrays give the better results. Taking detection results and convenience of field exploration work into consideration, these two methods are more suitable for practical application; bilateral observation method of four-electrode array is not suitable for the detection of the steep ore bodies. 展开更多
关键词 IP electrica-1 sounding multi-channel observation deep exploration inversion imaging
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Design of multi-channel data acquisition system based on LabVIEW and NI PXI-5105 被引量:4
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作者 解亚妮 张志杰 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第1期7-12,共6页
A data acquisition system based on LabVIEW and NI PXI-5105 is presented for multi-channel data acquisition. It can realize the functions of parameter setting, data acquisition and storage, waveform display and data an... A data acquisition system based on LabVIEW and NI PXI-5105 is presented for multi-channel data acquisition. It can realize the functions of parameter setting, data acquisition and storage, waveform display and data analysis using LabVIEW and NI-SCOPE device driver. The advantages of the system are that the setting is convenient, the operation is easy, the interface is friendly and the functions are practical. The experiment results show that the system has good stability and high reliability and is a powerful tool for multi-channel data acquisition. 展开更多
关键词 LABVIEW multi-channel data acquisition PXI-5105
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风电机组试验平台五自由度电液伺服控制系统设计
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作者 王甲 张永明 +1 位作者 陈国初 祝慧林 《轴承》 北大核心 2026年第1期50-57,共8页
风电轴承试验平台电液伺服控制系统通常采用PLC,DSP或成熟的信号采集卡与运动控制卡作为电控系统的核心,当需要控制的液压缸数量较多时会存在液压缸之间协同控制比较困难的问题。提出了一种基于Zynq的电液伺服加载控制系统:采用MKZ801F... 风电轴承试验平台电液伺服控制系统通常采用PLC,DSP或成熟的信号采集卡与运动控制卡作为电控系统的核心,当需要控制的液压缸数量较多时会存在液压缸之间协同控制比较困难的问题。提出了一种基于Zynq的电液伺服加载控制系统:采用MKZ801F.14型伺服阀放大器并设计了基于DAC71408芯片的多通道模数转换单元进行CSDM631型射流管电液伺服阀的驱动,解决了六轴同步驱动控制的问题;采用Block Design的方式设计控制系统,对多通道同步数据采集、多通道驱动信号同步发生单元进行了IP核设计;通过AMESim与Simulink联合仿真验证后,采用基于模型设计的方法进行自动代码生成并设计了API接口以配合多通道模数/数模单元的IP核,实现了复杂控制算法以及载荷模型的快速部署验证。试验结果表明,基于Zynq的电液伺服控制系统能够满足风电轴承试验平台5个自由度的电控要求。 展开更多
关键词 滚动轴承 风力发电机组 伺服控制系统 模型设计 多通道 数模转换
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A maximum-independent-set-based channel allocation algorithm for multi-channel wireless networks
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作者 余旭涛 施小翔 曾绍祥 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期12-18,共7页
A channel allocation algorithm based on the maximum independent set is proposed to decrease network conflict and improve network performance. First, a channel allocation model is formulated and a series of the maximum... A channel allocation algorithm based on the maximum independent set is proposed to decrease network conflict and improve network performance. First, a channel allocation model is formulated and a series of the maximum independent sets (MISs) are obtained from a contention graph by the proposed approximation algorithm with low complexity. Then, a weighted contention graph is obtained using the number of contention vertices between two MISs as a weighted value. Links are allocated to channels by the weighted contention graph to minimize conflicts between independent sets. Finally, after channel allocation, each node allocates network interface cards (NICs) to links that are allocated channels according to the queue lengths of NICs. Simulations are conducted to evaluate the proposed algorithm. The results show that the proposed algorithm significantly improves the network throughput and decreases the end to end delay. 展开更多
关键词 wireless networks multi-channel channelaUocation maximum independent set
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基于Multi-Radio Multi-Channel传感器网络无冲突信道分配算法的研究 被引量:2
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作者 蔡凤丽 刘新永 《吉林工程技术师范学院学报》 2014年第5期95-96,共2页
为降低通信冲突和信道干扰,对Mult-i Radio Mult-i Channel传感器网络无冲突信道进行研究,结果证实在网络通信半径大于3倍的网络最大功率通信半径的前提下,Sensor节点规模满足2倍网络功率级数加1的环境下,网络无冲突信道分配的信道数达... 为降低通信冲突和信道干扰,对Mult-i Radio Mult-i Channel传感器网络无冲突信道进行研究,结果证实在网络通信半径大于3倍的网络最大功率通信半径的前提下,Sensor节点规模满足2倍网络功率级数加1的环境下,网络无冲突信道分配的信道数达到网络信道冲突图的最大值。文章通过对无冲突信道算法的运用,最终证实其可以有效地提高传感器网络的工作效率,大幅度提升网络的吞吐量。 展开更多
关键词 MULTI-RADIO multi-channel 传感器网络 无冲突信道信道分配
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基于PCIe的链式DMA控制器设计与实现
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作者 王洪良 郭振华 +3 位作者 牟奇 卢圣才 徐亚明 于泉泉 《计算机研究与发展》 北大核心 2026年第1期28-40,共13页
近年来,国产可编程门阵列(field programmable gate array,FPGA)厂商虽发展迅速,但在数据中心部署FPGA异构加速器时仍面临挑战。相较于赛灵思、英特尔等国际厂商,国产厂商普遍缺乏PCIe设备与主机间高速传输的解决方案,尤其在高性能直接... 近年来,国产可编程门阵列(field programmable gate array,FPGA)厂商虽发展迅速,但在数据中心部署FPGA异构加速器时仍面临挑战。相较于赛灵思、英特尔等国际厂商,国产厂商普遍缺乏PCIe设备与主机间高速传输的解决方案,尤其在高性能直接内存访问(direct memory access,DMA)控制器设计领域存在明显短板。为解决该问题,设计并实现了基于PCIe的多通道链式DMA控制器。采用独立描述符控制器管理各通道,共享数据搬移器,降低对FPGA逻辑资源的消耗。采用链式结构实现描述符管理,减少中断对CPU的压力,满足主机与设备连续高速传输的需求。创新性地构建内部信息异步与预处理的架构,实现数据流水化处理,显著提升带宽利用率以及传输性能。经测试,在PCIe Gen3x8下,主机与国产FPGA加速器之间的DMA带宽高达6.91 GBps(利用率86%),支持多达16通道且实现通道负载均衡,该设计有效支撑了国产FPGA异构加速器在数据中心场景下的规模化部署。 展开更多
关键词 PCIE FPGA 异构加速 多通道 链式DMA
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多通道协议ALG安全策略在视频会议系统中的会话保持技术实现
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作者 杨佳霈 《计算机应用文摘》 2026年第1期214-216,共3页
随着视频会议系统的广泛应用,确保其流畅、安全与稳定运行成为关键。由于系统依赖的SIP,H.323等通道应用层协议在数据传输中呈现的复杂性,提出了基于应用层网关的多通道协议ALG安全策略。该策略通过深度解析应用层协议、动态维护会话状... 随着视频会议系统的广泛应用,确保其流畅、安全与稳定运行成为关键。由于系统依赖的SIP,H.323等通道应用层协议在数据传输中呈现的复杂性,提出了基于应用层网关的多通道协议ALG安全策略。该策略通过深度解析应用层协议、动态维护会话状态并执行地址与端口转换,保障视频会议在复杂网络环境中的连续性和安全性。 展开更多
关键词 多通道协议ALG 视频会议系统 会话保持技术 安全策略
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Performance analysis of multi-channel order statistics detector for range-spread target 被引量:5
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作者 Shuwen Xu Penglang Shui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第5期689-699,共11页
The problem of two order statistics detection schemes for the detection of a spatially distributed target in white Gaussian noise are studied.When the number of strong scattering cells is known,we first show an optima... The problem of two order statistics detection schemes for the detection of a spatially distributed target in white Gaussian noise are studied.When the number of strong scattering cells is known,we first show an optimal detector,which requires many processing channels.The structure of such optimal detector is complex.Therefore,a simpler quasi-optimal detector is then introduced.The quasi-optimal detector,called the strong scattering cells’ number dependent order statistics(SND-OS) detector,takes the form of an average of maximum strong scattering cells with a known number.If the number of strong scattering cells is unknown in real situation,the multi-channel order statistics(MC-OS) detector is used.In each channel,a various number of maximums scattered from target are averaged.Then,the false alarm probability analysis and thresholds sets for each channel are given,following the detection results presented by means of Monte Carlo simulation strategy based on simulated target model and three measured targets.In particular,the theoretical analysis and simulation results highlight that the MC-OS detector can efficiently detect range-spread targets in white Gaussian noise. 展开更多
关键词 order statistics strong scattering cell multi-channel range-spread target
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A multi-channel chemical sensor and its application in detecting hydrothermal vents 被引量:2
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作者 Zhen Cai A J Mur Luis +3 位作者 Jiwan Han Kui Wang Huawei Qin Ying Ye 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第9期128-134,共7页
There are well-established chemical and turbidity anomalies in the plumes occurring vicinity of hydrothermal vents, which are used to indicate their existence and locations. We here develop a small, accurate multi-cha... There are well-established chemical and turbidity anomalies in the plumes occurring vicinity of hydrothermal vents, which are used to indicate their existence and locations. We here develop a small, accurate multi-channel chemical sensor to detect such anomalies which can be used in deep-sea at depths of more than 4 000 m. The design allowed five all-solid-state electrodes to be mounted on it and each (apart from one reference electrode) could be changed according to chemicals to be measured. Two experiments were conducted using the chemical sensors. The first was a shallow-sea trial which included sample measurements and in situ monitoring. pH, Eh, CO3^2- and SO4^2- electrodes were utilized to demonstrate that the chemical sensor was accurate and stable outside the laboratory. In the second experiment, the chemical sensor was integrated with pH, Eh, CO3^2- and H2S electrodes, and was used in 29 scans of the seabed along the Southwest Indian Ridge (SWIR) to detect hydrothermal vents, from which 27 sets of valid data were obtained. Hydrothermal vents were identified by analyzing the chemical anomalies, the primary judging criteria were decreasing voltages of Eh and H2S, matched by increasing voltages of pH and CO3^2- . We proposed that simultaneous detection of changes in these parameters will indicate a hydrothermal vent. Amongst the 27 valid sets of data, five potential hydrothermal vents were targeted using the proposed method. We suggest that our sensors could be widely employed by marine scientists. 展开更多
关键词 CHEMICAL sensor multi-channel HYDROTHERMAL VENTS detection CHEMICAL ANOMALIES SWIR
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A time-sharing multi-channel pulse amplitude analyzer 被引量:2
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作者 Lian-Jun Jiang Xiang Zhou +1 位作者 Tong-Yu Wu Ze-Jie Yin 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第4期91-96,共6页
A conventional multi-channel pulse amplitude analyzer acquires single energy spectrum,but provides no information on its tendency with time.To address the limitation,we propose a scheme of time-sharing multichannel pu... A conventional multi-channel pulse amplitude analyzer acquires single energy spectrum,but provides no information on its tendency with time.To address the limitation,we propose a scheme of time-sharing multichannel pulse amplitude analyzer(TSMCA).A dual-port random access memory is divided into two storage spaces,one for current energy spectrum data acquisition and another for previous energy spectrum data storage.The two tasks can be performed simultaneously,and the time-related variation tendency of energy spectrum can be obtained.A prototype system of TSMCA is designed.It performs nicely,with maximum channel number of 4096 in capacity of 2^(32)/Ch,minimal time-sharing slice of 25 ms,the differential nonlinearity of <1.5%,and the integral nonlinearity of <0.3%. 展开更多
关键词 multi-channel pulse AMPLITUDE ANALYZER MCA Time-sharing ADC DUAL-PORT RAM
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Cutaneous sensory nerve as a substitute for auditory nerve in solving deaf-mutes' hearing problem: an innovation in multi-channel-array skin-hearing technology 被引量:2
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作者 Jianwen Li Yan Li +2 位作者 Ming Zhang Weifang Ma Xuezong Ma 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第16期1532-1540,共9页
The current use of hearing aids and artificial cochleas for deaf-mute individuals depends on their auditory nerve. Skin-hearing technology, a patented system developed by our group, uses a cutaneous sensory nerve to s... The current use of hearing aids and artificial cochleas for deaf-mute individuals depends on their auditory nerve. Skin-hearing technology, a patented system developed by our group, uses a cutaneous sensory nerve to substitute for the auditory nerve to help deaf-mutes to hear sound. This paper introduces a new solution, multi-channel-array skin-hearing technology, to solve the problem of speech discrimination. Based on the filtering principle of hair cells, external voice sig- nals at different frequencies are converted to current signals at corresponding frequencies using electronic multi-channel bandpass filtering technology. Different positions on the skin can be stimulated by the electrode array, allowing the perception and discrimination of external speech signals to be determined by the skin response to the current signals. Through voice frequen- cy analysis, the frequency range of the band-pass filter can also be determined. These findings demonstrate that the sensory nerves in the skin can help to transfer the voice signal and to dis- tinguish the speech signal, suggesting that the skin sensory nerves are good candidates for the replacement of the auditory nerve in addressing deaf-mutes' hearing problems. Scientific hearing experiments can be more safely performed on the skin. Compared with the artificial cochlea, multi-channel-array skin-hearing aids have lower operation risk in use, are cheaper and are more easily popularized. 展开更多
关键词 nerve regeneration peripheral nerve skin-hearing multi-channel electrode array aid DEAF band-pass filter voice NSFC grant neural regeneration
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Receding Horizon Estimation for Linear Discrete-time Systems with Multi-channel Observation Delays 被引量:2
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作者 Chunyan Han Chaochao Li +1 位作者 Fang He Yue Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第2期478-484,共7页
This paper investigates the receding horizon state estimation for the linear discrete-time system with multi-channel observation delays. The receding horizon estimation is designed by the reorganized observation techn... This paper investigates the receding horizon state estimation for the linear discrete-time system with multi-channel observation delays. The receding horizon estimation is designed by the reorganized observation technique and the linear unbiased estimation method. The estimation gains are developed by solving a set of Riccati equations, and a stability result about the state estimation is shown. Finally, an example is given to illustrate the efficiency of the receding horizon state estimation. 展开更多
关键词 multi-channel OBSERVATION DELAYS receding HORIZON ESTIMATION reorganized OBSERVATION STABILITY analysis
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A Multi-Gap Multi-Channel Gas Switch for the Linear Transformer Driver 被引量:3
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作者 刘轩东 梁天学 +4 位作者 孙凤举 姜晓峰 李佳 孙福 邱爱慈 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第6期725-729,共5页
A multi-gap and multi-channel gas switch with convexo-convex discal planet electrodes was designed and investigated. Eight gaps are formed in series by a trigger electrode, six intermediate electrodes and two high vol... A multi-gap and multi-channel gas switch with convexo-convex discal planet electrodes was designed and investigated. Eight gaps are formed in series by a trigger electrode, six intermediate electrodes and two high voltage electrodes with a uniform gap length of 5 ram. The self breakdown and triggered breakdown performance of the switch are reported. Both the delay time and jitter decrease with the increase in the trigger voltage, switching coefficient and the decrease in the trigger isolating resistor. The delay time of the switch is about 40 ns, and the jitter is less than 2 ns when charged with 4-85 kV and triggered by a voltage pule of -75 kV. The inductance of the switch is about 30 nH. 展开更多
关键词 multi-gap multi-channel gas spark closing switch linear transformer driver delay time JITTER
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Multi-channel 28-GHz millimeter-wave signal generation on a silicon photonic chip with automated polarization control 被引量:2
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作者 Ruiyuan Cao Yu He +4 位作者 Qingming Zhu Jingchi Li Shaohua An Yong Zhang Yikai Su 《Journal of Semiconductors》 EI CAS CSCD 2019年第5期33-39,共7页
We propose and experimentally demonstrate an integrated silicon photonic scheme to generate multi-channel millimeter-wave(MMW) signals for 5 G multi-user applications. The fabricated silicon photonic chip has a footpr... We propose and experimentally demonstrate an integrated silicon photonic scheme to generate multi-channel millimeter-wave(MMW) signals for 5 G multi-user applications. The fabricated silicon photonic chip has a footprint of 1.1 × 2.1 mm^2 and integrates 7 independent channels each having on-chip polarization control and heterodyne mixing functions. 7 channels of4-Gb/s QPSK baseband signals are delivered via a 2-km multi-core fiber(MCF) and coupled into the chip with a local oscillator(LO) light. The polarization state of each signal light is automatically adjusted and aligned with that of the LO light, and then 7 channels of 28-GHz MMW carrying 4-Gb/s QPSK signals are generated by optical heterodyne beating. Automated polarizationcontrol function of each channel is also demonstrated with ~7-ms tuning time and ~27-dB extinction ratio. 展开更多
关键词 multi-channel millimeter-wave(MMW) generation SILICON PHOTONIC integrated circuits SILICON polarization control(SPC)
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Joint channel assignment and cross-layer routing protocol for multi-radio multi-channel Ad Hoc networks 被引量:2
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作者 Yang Lu Junming Guan +1 位作者 Zhen Wei Qilin Wu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1095-1102,共8页
To study multi-radio multi-channel (MR-MC) Ad Hoc networks based on 802.11, an efficient cross-layer routing protocol with the function of joint channel assignment, called joint channel assignment and cross-layer ro... To study multi-radio multi-channel (MR-MC) Ad Hoc networks based on 802.11, an efficient cross-layer routing protocol with the function of joint channel assignment, called joint channel assignment and cross-layer routing (JCACR), is presented. Firstly, this paper introduces a new concept called channel utilization percentage (CUP), which is for measuring the contention level of different channels in a node’s neighborhood, and deduces its optimal value for determining whether a channel is overloaded or not. Then, a metric parameter named channel selection metric (CSM) is designed, which actually reffects not only the channel status but also corresponding node’s capacity to seize it. JCACR evaluates channel assignment by CSM, performs a local optimization by assigning each node a channel with the smaller CSM value, and changes the working channel dynamically when the channel is overloaded. Therefore, the network load balancing can be achieved. In addition, simulation shows that, when compared with the protocol of weighted cumulative expected transfer time (WCETT), the new protocol can improve the network throughput and reduce the end-to-end average delay with fewer overheads. 展开更多
关键词 Ad Hoc network multi-radio multi-channel channel assignment routing protocol channel utilization percentage.
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Multi-Channel Iterative FDE for Single Carrier Block Transmission over Underwater Acoustic Channels 被引量:3
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作者 HE Chengbing HUO Siyu +2 位作者 ZHANG Qunfei WANG Han HUANG Jianguo 《China Communications》 SCIE CSCD 2015年第8期55-61,共7页
Recently, single carrier block transmission(SCBT) has received much attention in high-rate phase-coherent underwater acoustic communication.However,minimum-mean-square-error(MMSE) linear FDE may suffer performance los... Recently, single carrier block transmission(SCBT) has received much attention in high-rate phase-coherent underwater acoustic communication.However,minimum-mean-square-error(MMSE) linear FDE may suffer performance loss in the severely time dispersive underwater acoustic channel. To combat the channel distortion, a novel multi-channel receiver with maximum ratio combining and a low complex T/4 fractional iterative frequency domain equalization(FDE) is investigated to improve diversity gain and the bit error rate(BER) performance. The proposed method has been verified by the real data from a lake underwater acoustic communication test in November 2011. At 1.8 km, the useful data rates are around 1500 and 3000 bits/s for BPSK and QPSK respectively. The results show the improvements of system performance. Compared with MMSE FDE system, the output SNR improvement is 6.9 d B, and the BER is from 10-3 to no error bits for BPSK. The output SNR improvement is 5.3 d B, and the BER is from 1.91×10-2 to 2.2×10-4for QPSK. 展开更多
关键词 underwater acoustic communi-cation single carrier multi-channel frequency domain equalization iterative processing
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