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Performance Analysis of Bandwidth Aware Hybrid Powered 5G Cloud Radio Access Network
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作者 Md.Al-Hasan Mst.Rubina Aktar +3 位作者 Fahmid Al Farid Md.Shamim Anower Abu Saleh Musa Miah Md.Hezerul Abdul Karim 《Computers, Materials & Continua》 2026年第4期2146-2160,共15页
The rapid growth in available network bandwidth has directly contributed to an exponential increase in mobile data traffic,creating significant challenges for network energy consumption.Also,with the extraordinary gro... The rapid growth in available network bandwidth has directly contributed to an exponential increase in mobile data traffic,creating significant challenges for network energy consumption.Also,with the extraordinary growth of mobile communications,the data traffic has dramatically expanded,which has led to massive grid power consumption and incurred high operating expenditure(OPEX).However,the majority of current network designs struggle to efficientlymanage a massive amount of data using little power,which degrades energy efficiency performance.Thereby,it is necessary to have an efficient mechanism to reduce power consumption when processing large amounts of data in network data centers.Utilizing renewable energy sources to power the Cloud Radio Access Network(C-RAN)greatly reduces the need to purchase energy from the utility grid.In this paper,we propose a bandwidth-aware hybrid energypowered C-RAN that focuses on throughput and energy efficiency(EE)by lowering grid usage,aiming to enhance the EE.This paper examines the energy efficiency,spectral efficiency(SE),and average on-grid energy consumption,dealing with the major challenges of the temporal and spatial nature of traffic and renewable energy generation across various network setups.To assess the effectiveness of the suggested network by changing the transmission bandwidth,a comprehensive simulation has been conducted.The numerical findings support the efficacy of the suggested approach. 展开更多
关键词 5G bandwidth renewable energy energy efficiency spectral efficiency C-RAN
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Read-Write Dependency Aware Register Allocation
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作者 Sheng Xiao Yong Chen +1 位作者 Jing He Xi Yang 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期3527-3540,共14页
Read-write dependency is an important factor restricting software efficiency.Timing Speculative(TS)is a processing architecture aiming to improve energy efficiency of microprocessors.Timing error rate,influenced by th... Read-write dependency is an important factor restricting software efficiency.Timing Speculative(TS)is a processing architecture aiming to improve energy efficiency of microprocessors.Timing error rate,influenced by the read-write dependency,bottlenecks the voltage down-scaling and so the energy efficiency of TS processors.We proposed a method called Read-Write Dependency Aware Register Allocation.It is based on the Read-Write Dependency aware Interference Graph(RWDIG)conception.Registers are reallocated to loosen the read-write dependencies,so resulting in a reduction of timing errors.The traditional no operation(Nop)padding method is also redesigned to increase the distance value to above 2.We analyzed the dependencies of registers and maximized the average distance value of read and write dependencies.Experimental results showed that we can reduce all read-write dependency by Nop padding,as well as the overhead timing errors.An energy saving of approximately 7%was achieved. 展开更多
关键词 read-write dependency timing speculative energy efficiency
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Unified Bandwidth Scheduling in Centralized Fixed Access Network(C-FAN)
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作者 Li Jun Lu Xiang +3 位作者 Wang Xiang Chang Tianghai Sanjay Kumar Bose Shen Gangxiang 《China Communications》 2025年第1期196-215,共20页
Time Division Multiplexing-Passive Optical Networks(TDM-PONs)play a vital role in Fiberto-the-Home(FTTH)deployments.To improve the service quality of home networks,FTTH is expanding to the Fiber-to-the-Room(FTTR)scena... Time Division Multiplexing-Passive Optical Networks(TDM-PONs)play a vital role in Fiberto-the-Home(FTTH)deployments.To improve the service quality of home networks,FTTH is expanding to the Fiber-to-the-Room(FTTR)scenario,where fibers are deployed to connect individual rooms(i.e.,Fiber In-premises Network(FIN)in the ITU-T G.9940 standard).In this scenario,a point-to-multipoint(P2MP)fiber network is deployed as FTTR FIN to offer gigabit access to each room,which forms a two-tier cascaded network together with the FTTH segment.To optimize the capacity utilization of the cascaded network and reduce the overall system cost,a centralized architecture,known as Centralized Fixed Access Network(C-FAN),has been introduced.C-FAN centralizes the medium access control(MAC)modules of both the FTTH and FTTR networks at the FTTH’s Optical Line Terminal(OLT)for unified control and management of the cascaded network.We develop a unified bandwidth scheduling protocol by extending the ITU-T PON standard for both the upstream and downstream directions of C-FAN.We also propose a unified dynamic bandwidth allocation(UDBA)algorithm for efficient bandwidth allocation for multiple traffic flows in the two-tier cascaded network.Simulations are conducted to evaluate the performance of the proposed control protocol and the UDBA algorithm.The results show that,in comparison to the conventional DBA algorithm,the UDBA algorithm can utilize upstream bandwidth more efficiently to reduce packet delay and loss,without adversely impacting downstream transmission performance. 展开更多
关键词 ARCHITECTURE dynamic bandwidth allocation FTTH FTTR PON
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Tunable working bandwidth terahertz switch based on magnetic valley photonic crystal
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作者 Mingxia Hou Hongming Fei +1 位作者 Han Lin Mingda Zhang 《Chinese Physics B》 2025年第5期627-634,共8页
Terahertz(THz)switches are essential components of THz communication systems.THz switches based on conventional waveguides and photonic crystal structures are sensitive to manufacturing defects and sharp bending,resul... Terahertz(THz)switches are essential components of THz communication systems.THz switches based on conventional waveguides and photonic crystal structures are sensitive to manufacturing defects and sharp bending,resulting in high scattering losses.In addition,THz switches with tunable working bandwidths have not yet been demonstrated.Here,we design THz switches based on a topological valley photonic crystal(VPC)structure using magnetic materials,which can achieve high forward transmittance based on the unique spin–valley locking effect.The broad working bandwidth allows selective turning on and off at a designed wavelength region by controlling the applied magnetic field.The designed THz switch can achieve an extinction ratio of up to 31.66 dB with an insertion loss of less than 0.13 dB.The 3-dB bandwidth is up to 49 GHz.This tunable THz switch can be experimentally fabricated by current fabrication techniques and thus can find broad applications in THz communication systems. 展开更多
关键词 terahertz switch magnetic material valley photonic crystal tunable bandwidth
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Equivalent Bandwidth Concept and Its Usage in the Network Selection
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作者 Ma Anhua Pan Su Zhou Weiwei 《China Communications》 2025年第2期213-225,共13页
Maximize the resource utilization efficiency and guarantee the quality of service(QoS)of users by selecting the network are the key issues for heterogeneous network operators,but the resources occupied by users in dif... Maximize the resource utilization efficiency and guarantee the quality of service(QoS)of users by selecting the network are the key issues for heterogeneous network operators,but the resources occupied by users in different networks cannot be compared directly.This paper proposes a network selection algorithm for heterogeneous network.Firstly,the concept of equivalent bandwidth is proposed,through which the actual resources occupied by users with certain QoS requirements in different networks can be compared directly.Then the concept of network applicability is defined to express the abilities of networks to support different services.The proposed network selection algorithm first evaluates whether the network has enough equivalent bandwidth required by the user and then prioritizes network with poor applicability to avoid the situation that there are still residual resources in entire network,but advanced services can not be admitted.The simulation results show that the proposed algorithm obtained better performance than the baselines in terms of reducing call blocking probability and improving network resource utilization efficiency. 展开更多
关键词 call blocking probability equivalent bandwidth heterogeneous network network applicability
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Hollow engineering in CoNi@Air@C@MoS_(2) multicomponent composites derived from bimetallic CoNi Prussian blue analogs for ultra-wide bandwidth and strong electromagnetic wave absorption
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作者 Ziqing Yang Qiqin Liang +8 位作者 Xiaosi Qi Beibei Zhan Xiu Gong Yunpeng Qu Junfei Ding Jing-Liang Yang Yanli Chen Qiong Peng Wei Zhong 《Journal of Materials Science & Technology》 2025年第9期35-43,共9页
In recent years,two-dimensional layered transition metal dichalcogenides-based multicomponent com-posites(MCCs)acting as electromagnetic wave(EMW)materials have received intensive investiga-tions.However,the vulcanica... In recent years,two-dimensional layered transition metal dichalcogenides-based multicomponent com-posites(MCCs)acting as electromagnetic wave(EMW)materials have received intensive investiga-tions.However,the vulcanication of metal greatly hindered their enhancement of EMW absorption per-formances(EMWAPs).Herein,a combined metal-organic frameworks-derived and hydrothermal strat-egy was presented to produce yolk-shell structure(YSS)CoNi@Air@C@MoS_(2) MCCs.The results showed that the thermal and hydrothermal treatments resulted in the generation of YSS and two-dimensional MoS_(2) nanosheets,which maintained the original morphology of CoNi Prussian blue analogues.The pro-tection of thick C layer well inhibited the vulcanization of inner CoNi alloy.The formed sheet-like MoS_(2) further optimized impedance matching characteristics,which led to the satisfactory EMWAPs of CoNi@Air@C@MoS_(2) MCCs.Furthermore,the EMWAPs could be further improved by optimizing the Ni:Co atom ratios CoNi@Air@C@MoS_(2) MCCs,which stemmed from their boosted impedance matching perfor-mances,EMW attention and polarization loss abilities.The absorption bandwidth and reflection loss val-ues for YSS CoNi@Air@C@MoS_(2) MCCs are 8 GHz and−60.83 dB,which covered almost all C-Ku bands.In general,our research work provided a valid strategy to produce YSS magnetic CoNi@Air@C@MoS_(2) MCCs with high efficiency,which well avoided the vulcanization of metal nanoparticles,made best of hollow engineering and atomic ratio optimization strategy to boost the comprehensive EMWAPs. 展开更多
关键词 Hollow engineering CoNi@Air@C@MoS_(2) Polarization loss Ultra-wide bandwidth Microwave absorption
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Pulse duration tunable ultra-narrow bandwidth mode-locked lasers
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作者 Weixi Li Lilong Dai +8 位作者 Qianqian Huang Meng Zou Xiangpeng Xiao Siyu Luo Siyu Chen Yingxiong Song Yunqi Liu Zhijun Yan Chengbo Mou 《Advanced Photonics Nexus》 2025年第3期168-175,共8页
Ultra-narrow bandwidth mode-locked lasers with tunable pulse duration can be versatile light sources for diverse applications.However,the spectral-temporal control of a narrow bandwidth mode-locked laser is challengin... Ultra-narrow bandwidth mode-locked lasers with tunable pulse duration can be versatile light sources for diverse applications.However,the spectral-temporal control of a narrow bandwidth mode-locked laser is challenging due to limited gain and nonlinearity,hindering practical applications of such lasers.We demonstrate a pulse duration widely tunable mode-locked ultra-narrow bandwidth laser using a composite filtering mechanism and a single-wall carbon nanotube.The laser pulse duration can be adjusted from 481 ps to 1.38 ns,which is the widest tuning range achieved in narrow-bandwidth passively mode-locked lasers.When the pulse duration is 1.38 ns,the corresponding spectral width reaches 4 pm(502 MHz).Numerical simulations support the experimental results and show that the evolution of long pulses in the laser cavity behaves similarly to a quasi-continuous wave with a low breathing ratio.We have not only designed a simple and flexible tunable scheme for the dilemma of spectral-temporal control in narrow-bandwidth mode-locked fiber lasers but also provided a unique and idealized light source for various applications that takes into account robust output. 展开更多
关键词 mode-locked fiber laser ultra-narrow bandwidth nanosecond pulse single-walled carbon nanotube spectral-temporal control
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Correction:Initiating Binary Metal Oxides Microcubes Electromagnetic Wave Absorber Toward Ultrabroad Absorption Bandwidth Through Interfacial and Defects Modulation
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作者 Fushan Li Nannan Wu +8 位作者 Hideo Kimura Yuan Wang Ben Bin Xu Ding Wang Yifan Li Hassan Algadi Zhanhu Guo Wei Du Chuanxin Hou 《Nano-Micro Letters》 2025年第11期530-533,共4页
Following publication of the original article[1],the authors found that they pasted the same data when drawing XRD for sample NCO-1 and NCO-2 in Fig.2a,however,the XRD of all four samples in the manuscript was tested,... Following publication of the original article[1],the authors found that they pasted the same data when drawing XRD for sample NCO-1 and NCO-2 in Fig.2a,however,the XRD of all four samples in the manuscript was tested,and XRD raw data were kept and can be offered.The correct Fig.2 has been provided in this Correction. 展开更多
关键词 binary metal oxides ultrabroad absorption bandwidth electromagnetic wave absorber interfacial modulation defects modulation XRD microcubes
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On the stability condition of active disturbance rejection control with time-varying bandwidth observer
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作者 Depeng Song Sen Chen +1 位作者 Wenchao Xue Zhiliang Zhao 《Control Theory and Technology》 2025年第3期464-478,共15页
With the growing adoption of artificial intelligence algorithms and neural networks,online learning and adaptive methods for updating the bandwidth have become increasingly prevalent.However,the conditions required to... With the growing adoption of artificial intelligence algorithms and neural networks,online learning and adaptive methods for updating the bandwidth have become increasingly prevalent.However,the conditions required to ensure closed-loop stability when employing a time-varying bandwidth,as well as the supporting mathematical foundations,remain insufficiently studied.This paper investigates the stability condition for active disturbance rejection control(ADRC)with a time-varying bandwidth extended state observer(ESO).A new stability condition is derived,which means that the upper bound of rate of change for ESO bandwidth should be restricted.Moreover,under the proposed condition,the closed-loop stability of ADRC with a time-varying bandwidth observer is rigorously proved for nonlinear uncertainties.In simulations,the necessity of the proposed condition is illustrated,demonstrating that the rate of change of ESO bandwidth is crucial for closed-loop stability. 展开更多
关键词 Active disturbance rejection control Time-varying bandwidth Extended state observer Closed-loop stability Rate of change
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Enhancing Bandwidth Allocation Efficiency in 5G Networks with Artificial Intelligence
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作者 Sarmad K.Ibrahim Saif A.Abdulhussien +1 位作者 Hazim M.ALkargole Hassan H.Qasim 《Computers, Materials & Continua》 2025年第9期5223-5238,共16页
The explosive growth of data traffic and heterogeneous service requirements of 5G networks—covering Enhanced Mobile Broadband(eMBB),Ultra-Reliable Low Latency Communication(URLLC),and Massive Machine Type Communicati... The explosive growth of data traffic and heterogeneous service requirements of 5G networks—covering Enhanced Mobile Broadband(eMBB),Ultra-Reliable Low Latency Communication(URLLC),and Massive Machine Type Communication(mMTC)—present tremendous challenges to conventional methods of bandwidth allocation.A new deep reinforcement learning-based(DRL-based)bandwidth allocation system for real-time,dynamic management of 5G radio access networks is proposed in this paper.Unlike rule-based and static strategies,the proposed system dynamically updates itself according to shifting network conditions such as traffic load and channel conditions to maximize the achievable throughput,fairness,and compliance with QoS requirements.By using extensive simulations mimicking real-world 5G scenarios,the proposed DRL model outperforms current baselines like Long Short-Term Memory(LSTM),linear regression,round-robin,and greedy algorithms.It attains 90%–95%of the maximum theoretical achievable throughput and nearly twice the conventional equal allocation.It is also shown to react well under delay and reliability constraints,outperforming round-robin(hindered by excessive delay and packet loss)and proving to be more efficient than greedy approaches.In conclusion,the efficiency of DRL in optimizing the allocation of bandwidth is highlighted,and its potential to realize self-optimizing,Artificial Intelligence-assisted(AI-assisted)resource management in 5G as well as upcoming 6G networks is revealed. 展开更多
关键词 5G bandwidth allocation DRL for 5G AI-based resource management QoS optimization for 5G networks dynamic spectrum allocation SON
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三相四线制逆变器独立中线模块的高带宽复合控制策略与参数优化设计方法
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作者 赵景涛 雷家兴 +2 位作者 郑舒 吴志 陈永华 《中国电机工程学报》 北大核心 2026年第3期1165-1177,I0025,共14页
带独立中线模块的三相四线制逆变器具有零序电流小、输出中点电压与三相电压控制解耦等优势,其正常运行的基础是中点电压稳定。传统的比例-积分(proportional integral,PI)双环控制策略受制于其有限带宽,对中点电压波动的抑制效果不足,... 带独立中线模块的三相四线制逆变器具有零序电流小、输出中点电压与三相电压控制解耦等优势,其正常运行的基础是中点电压稳定。传统的比例-积分(proportional integral,PI)双环控制策略受制于其有限带宽,对中点电压波动的抑制效果不足,易引起输出共模扰动、降低波形质量。为此,提出一种内环状态反馈和外环PI复合的中点电压控制策略及基于目标响应驱动的控制参数优化设计方法。所提策略在离散域建立受控对象的精细化数学模型,基于系统整体设计理念,通过预设目标传递函数逆向获得所有控制参数的解析表达式,并分析系统可实现控制带宽与闭环零极点位置之间的量化关系;在此基础上,研究不同控制带宽下系统对零序电流低频分量的抑制效果及采样延时和噪声对控制性能的影响规律,为实际应用中控制参数的最优设计提供指导;同时,分析滤波参数宽幅变化对系统闭环控制性能的影响。实验结果表明,所提方法可在不放大噪声的同时显著提高控制带宽,进而有效抑制不对称/谐波负载扰动下的中点电压波动、提高输出波形质量,且具有较高的参数鲁棒性。 展开更多
关键词 独立中线模块 中点电压波动 状态反馈控制 高带宽
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苏北盆地地震激发接收因素分析
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作者 薛野 《西安石油大学学报(自然科学版)》 北大核心 2026年第1期50-57,共8页
苏北盆地以隐蔽式复杂油藏勘探开发为主,对地震资料精度要求高。针对区内障碍物密集、近地表岩性复杂、表层吸收衰减作用强等复杂地表条件,系统开展了地震激发与接收因素试验,优选出“黏土或粉质黏土激发岩性、4 kg炸药药量、单井”激... 苏北盆地以隐蔽式复杂油藏勘探开发为主,对地震资料精度要求高。针对区内障碍物密集、近地表岩性复杂、表层吸收衰减作用强等复杂地表条件,系统开展了地震激发与接收因素试验,优选出“黏土或粉质黏土激发岩性、4 kg炸药药量、单井”激发方式,建立了优势岩性逐点井深设计技术,提出在城镇区利用可控震源辅助提高中浅层资料完整性以及利用低频检波器加强低频信息采集的技术对策;与前期资料相比,新采集单炮记录地震有效频带低频端由8 Hz拓宽至2 Hz、深层反射信噪比更高,新资料处理剖面频带宽度拓宽15 Hz,信噪比提高40%,火成岩下成像质量有较大提高。 展开更多
关键词 苏北盆地 地震采集 激发接收 频带宽度 信噪比 成像质量
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考虑节点功率和平均链路带宽的无线虚拟网络智能映射算法
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作者 张震 胡贵恒 盖昊宇 《兰州文理学院学报(自然科学版)》 2026年第1期50-55,共6页
针对无线虚拟网络智能映射常因资源分配不合理和映射效率低下,导致虚拟网络请求难以高效、合规地映射到物理网络的问题,提出一种考虑节点功率和平均链路带宽的无线虚拟网络智能映射算法.首先,计算物理网络和虚拟网络的节点功率资源和链... 针对无线虚拟网络智能映射常因资源分配不合理和映射效率低下,导致虚拟网络请求难以高效、合规地映射到物理网络的问题,提出一种考虑节点功率和平均链路带宽的无线虚拟网络智能映射算法.首先,计算物理网络和虚拟网络的节点功率资源和链路带宽资源,并设定其对应的约束条件;其次,按照可用资源将映射节点从高到低排列,同时找出虚拟网络的独立链路集;然后,在条件约束下,排除无效迭代计算过程,直接找出与虚拟节点对应的物理节点、与虚拟链路对应的物理链路,从而高效地完成无线虚拟网络的智能映射.实验结果表明,所提方法在物理网络平均收益和虚拟网络平均接受率方面表现良好,同时在虚拟网络消耗和链路映射平均跳数方面也有显著的优化效果. 展开更多
关键词 平均链路带宽 独立链路集 无线虚拟网络映射 权值系数 节点功率
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A distributed on-demand bandwidth-constrained multicast routing protocol for wireless ad hoc networks 被引量:1
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作者 余燕平 倪玲玲 郑元琰 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期5-11,共7页
To meet the bandwidth requirement for the multicasting data flow in ad hoc networks, a distributed on- demand bandwidth-constrained multicast routing (BCMR) protocol for wireless ad hoc networks is proposed. With th... To meet the bandwidth requirement for the multicasting data flow in ad hoc networks, a distributed on- demand bandwidth-constrained multicast routing (BCMR) protocol for wireless ad hoc networks is proposed. With this protocol, the resource reservation table of each node will record the bandwidth requirements of data flows, which access itself, its neighbor nodes and hidden nodes, and every node calculates the remaining available bandwidth by deducting the bandwidth reserved in the resource reservation table from the total available bandwidth of the node. Moreover, the BCMR searches in a distributed manner for the paths with the shortest delay conditioned by the bandwidth constraint. Simulation results demonstrate the good performance of BCMR in terms of packet delivery reliability and the delay. BCMR can meet the requirements of real time communication and can be used in the multicast applications with low mobility in wireless ad hoc networks. 展开更多
关键词 wireless ad hoc networks multicast routing bandwidth satisfaction on-demand multicast routing distributed multicast routing QoS multicast routing
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采用螺纹质量块结构的宽频带高温压电加速度传感器
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作者 杨凯博 樊青青 +1 位作者 马军 李俊红 《压电与声光》 北大核心 2026年第1期107-113,共7页
高温压电加速度传感器在核电、航空航天等领域有着重要应用。发动机等设备故障信号的特征频率主要集中在高频范围,因此,传感器需具备宽频域响应能力以实现对高频故障信号的有效监测。然而,现有国产高温加速度传感器存在频带窄的问题,难... 高温压电加速度传感器在核电、航空航天等领域有着重要应用。发动机等设备故障信号的特征频率主要集中在高频范围,因此,传感器需具备宽频域响应能力以实现对高频故障信号的有效监测。然而,现有国产高温加速度传感器存在频带窄的问题,难以满足实际应用需求。为此,本文设计了一种剪切式高温压电加速度传感器,采用具有高温稳定性的硼酸氧钙钇(YCOB)晶体作为压电敏感元件,并结合解析建模与有限元仿真方法对其性能进行系统分析与优化。此外,采用内置螺纹孔的质量块以增强连接稳定性,从而提升整体抗振性能。实验结果表明,该传感器在频率1 kHz下的电荷灵敏度为1.2 pC/g,谐振频率约为11 kHz,3 dB带宽可达6 kHz。该研究提升了传感器的频域响应范围,增强了其对高频故障信号的监测能力,具有良好的工程应用前景。 展开更多
关键词 硼酸氧钙钇(YCOB) 压电加速度传感器 高温 宽频带 剪切式
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双星并联光纤激光网络通信带宽自调节研究
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作者 王莉 李丹 沈玲玲 《激光杂志》 北大核心 2026年第1期143-148,共6页
为了有效优化双星并联光纤激光网络通信性能,提出一种双星并联光纤激光网络通信带宽自调节方法。将双星并联光纤激光网络通信带宽利用率最大化和通信节点的最坏延迟总和最小作为目标函数,以通信时延和误码率等作为约束条件,构建双星并... 为了有效优化双星并联光纤激光网络通信性能,提出一种双星并联光纤激光网络通信带宽自调节方法。将双星并联光纤激光网络通信带宽利用率最大化和通信节点的最坏延迟总和最小作为目标函数,以通信时延和误码率等作为约束条件,构建双星并联光纤激光网络通信带宽自调节模型。对粒子群方法展开改进,应用改进后的PSO方法对模型求解,确定通信带宽最优自调节方案。实验结果表明,所提方法在单次迭代时间上仅需5.1 ms,内存占用为35 MB,有效降低平均队列长度,提升上行信道利用率和带宽利用率,有效确保双星并联光纤激光网络的稳定性和可靠性。 展开更多
关键词 双星并联 光纤激光网络 通信带宽 自调节
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基于前馈修正-总误差补偿的频带扩展式复合振动台控制方法研究
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作者 丁振 梁建文 +4 位作者 韩庆华 吴昊 芦燕 刘铭劼 纪金豹 《工程力学》 北大核心 2026年第3期44-55,共12页
频带扩展式复合振动台(FBECST)作为一种新型地震模拟振动台,为同时实现长行程、宽频带激励提供了有效途径。FBECST由长行程振动台(主台)和高频振动台(扩展台)上下叠合而成,系统复杂度高。设计合适的补偿控制方法是实现FBECST高精度跟踪... 频带扩展式复合振动台(FBECST)作为一种新型地震模拟振动台,为同时实现长行程、宽频带激励提供了有效途径。FBECST由长行程振动台(主台)和高频振动台(扩展台)上下叠合而成,系统复杂度高。设计合适的补偿控制方法是实现FBECST高精度跟踪控制的前提。该文提出了一种基于前馈修正的总误差补偿控制方法,并分析了所提出方法的收敛性和稳定性;结合增益裕度理论给出了总误差反馈增益的取值方法;以逆补偿控制(IC)和离线迭代控制(OIC)为基准方法,对比验证了所提出方法的有效性和优势。一系列试验结果表明:所提出方法在时域和频域上的性能表现均优于IC和OIC,尤其在地震波的复现能力方面,所提出方法的优势更为显著。所提出方法仅需1次辨识和算法设计即可实现对FBECST系统的高精度补偿控制,对待测试件的影响极小。该文可为FBECST基于模型的补偿控制方法研究及工程应用提供有力支持。 展开更多
关键词 复合振动台 频带扩展 前馈修正 总误差补偿 增益裕度 稳定性分析
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高频宽带换能器1-3型匹配层研究
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作者 夏榕健 仲林建 夏铁坚 《声学技术》 北大核心 2026年第1期201-206,共6页
研究了一种用于制作高频水声换能器的铝-聚合物1-3型匹配层,并计算了其等效参数,进一步利用等效电路法进行计算,并建立了有限元模型开展有限元仿真,确定了满足设计需求的结构与参数。最终制作了一款换能器样品,并进行了水下发射电压响... 研究了一种用于制作高频水声换能器的铝-聚合物1-3型匹配层,并计算了其等效参数,进一步利用等效电路法进行计算,并建立了有限元模型开展有限元仿真,确定了满足设计需求的结构与参数。最终制作了一款换能器样品,并进行了水下发射电压响应测试。实测结果表明,该换能器工作频段为150~400 kHz,带内响应起伏为6 dB,发射响应峰值为169.8 dB,相对带宽为90.9%,在300 kHz时的指向性角度为6.3°。该匹配层的试验结果可作为后续弧形匹配层换能器研究的基础。 展开更多
关键词 高频换能器 宽带 1-3型匹配层 复合材料
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多向激励下的动力反共振隔振带宽优化研究
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作者 田雨 邓家磊 龙新华 《噪声与振动控制》 北大核心 2026年第1期29-33,48,共6页
旋翼气动载荷所致叶频及其倍频桨毂力和力矩是直升机振动的主要原因之一。在机体和主减速器之间安装动力反共振隔振器,可以降低直升机机体振动。然而,激励力多向性及直升机在不同飞行工况下叶频不一致会导致动力反共振隔振失效。为了解... 旋翼气动载荷所致叶频及其倍频桨毂力和力矩是直升机振动的主要原因之一。在机体和主减速器之间安装动力反共振隔振器,可以降低直升机机体振动。然而,激励力多向性及直升机在不同飞行工况下叶频不一致会导致动力反共振隔振失效。为了解决这一问题,通过对四撑杆杠杆式主减速器隔振平台进行动力学建模分析,提出一种基于粒子群算法的多向激励下复杂结构反共振点优化方法,用于实现动力反共振隔振器三向反共振频率及带宽的协同优化。数值结果表明,经优化的动力反共振隔振器组合具有多自由度振动传递控制的特点,能够在8 Hz左右的带宽内实现有效减振。此外,还通过结构的参数分析研究机身质量与撑杆刚度对系统隔振效果的影响。 展开更多
关键词 振动与波 动力反共振 带宽优化 多向激励 粒子群算法
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PREDICTION-BASED BANDWIDTH ALLOCATION FOR VBR TRAFFIC
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作者 金志刚 舒炎泰 +1 位作者 刘嘉焜 Oliver W W Yang 《Transactions of Tianjin University》 EI CAS 2001年第4期221-225,共5页
A prediction based bandwidth allocation scheme for transporting MPEG VBR traffic is proposed by using the FARIMA (p,d,q) (fractional autoregressive integrated moving average) model.FARIMA (p,d,q) model is capable of ... A prediction based bandwidth allocation scheme for transporting MPEG VBR traffic is proposed by using the FARIMA (p,d,q) (fractional autoregressive integrated moving average) model.FARIMA (p,d,q) model is capable of capturing both the long range and short range dependence in the video traffic.A method is suggested to simplify the FARIMA model fitting procedure and hence to reduce the time of traffic modeling and prediction.The simulation experiments show that this scheme can significantly reduce the requirement of buffer size and the frame loss rate. 展开更多
关键词 bandwidth allocation PREDICTION FARIMA model
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