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Multi-frequency formation mechanism and modulation strategy of self-priming enhanced submerged pulsed waterjet
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作者 Haojie Jia Yanwei Liu +6 位作者 Weiqin Zuo Hongkai Han Ping Chang Mohammad Waqar Ali Asad Guozhong Hu Jian Miao Hani SMitri 《International Journal of Mining Science and Technology》 2025年第2期175-189,共15页
Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure throug... Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure through self-priming. However, their pressure frequency and cavitation characteristics remain unclear, resulting in an inability to fully utilize resonance and cavitation erosion to break coal and rock. In this study, high-frequency pressure testing, high-speed photography, and large eddy simulation(LES) are used to investigate the distribution of the pressure frequency band, evolution law of the cavitation cloud, and its regulation mechanism of a continuous waterjet, SOPW, and AFESOPW. The results indicated that the excitation of the plunger pump, shearing layer vortex, and bubble collapse corresponded to the three high-amplitude frequency bands of the waterjet pressure. AFESOPWs have an additional self-priming frequency that can produce a larger amplitude under a synergistic effect with the second high-amplitude frequency band. A better cavitation effect was produced after self-priming the annulus fluid, and the shedding frequency of the cavitation clouds of the three types of waterjets was linearly related to the cavitation number. The peak pressure of the waterjet and cavitation erosion effect can be improved by modulating the waterjet pressure oscillation frequency and cavitation shedding frequency. 展开更多
关键词 MULTI-FREQUENCY modulation SELF-PRimING Submerged waterjet CAVITATION
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Optimization strategies for operational parameters of Rydberg atom-based amplitude modulation receiver
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作者 Yuhao Wu Dongping Xiao +1 位作者 Huaiqing Zhang Sheng Yan 《Chinese Physics B》 2025年第1期280-287,共8页
The Rydberg atom-based receiver, as a novel type of antenna, demonstrates broad application prospects in the field of microwave communications. However, since Rydberg atomic receivers are nonlinear systems, mismatches... The Rydberg atom-based receiver, as a novel type of antenna, demonstrates broad application prospects in the field of microwave communications. However, since Rydberg atomic receivers are nonlinear systems, mismatches between the parameters of the received amplitude modulation(AM) signals and the system's linear workspace and demodulation operating points can cause severe distortion in the demodulated signals. To address this, the article proposes a method for determining the operational parameters based on the mean square error(MSE) and total harmonic distortion(THD) assessments and presents strategies for optimizing the system's operational parameters focusing on linear response characteristics(LRC) and linear dynamic range(LDR). Specifically, we employ a method that minimizes the MSE to define the system's linear workspace, thereby ensuring the system has a good LRC while maximizing the LDR. To ensure that the signal always operates within the linear workspace, an appropriate carrier amplitude is set as the demodulation operating point. By calculating the THD at different operating points, the LRC performance within different regions of the linear workspace is evaluated, and corresponding optimization strategies based on the range of signal strengths are proposed. Moreover, to more accurately restore the baseband signal, we establish a mapping relationship between the carrier Rabi frequency and the transmitted power of the probe light, and optimize the slope of the linear demodulation function to reduce the MSE to less than 0.8×10^(-4). Finally, based on these methods for determining the operational parameters, we explore the effects of different laser Rabi frequencies on the system performance, and provide optimization recommendations. This research provides robust support for the design of high-performance Rydberg atom-based AM receivers. 展开更多
关键词 Rydberg atom-based receiver amplitude modulation(AM) operating parameters OPTimIZATION
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Comprehensive pan-cancer analysis of NCOA family members:insights into tumorigenesis,genomic alterations,and immune modulation
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作者 Xin Li Wan-Rong Li Hao Jin 《Cancer Advances》 2025年第3期1-9,共9页
Background:The nuclear receptor coactivator(NCOA)family,including NCOA1,NCOA2,and NCOA3,is critical in regulating gene expression through interactions with nuclear receptors and other transcription factors.These coact... Background:The nuclear receptor coactivator(NCOA)family,including NCOA1,NCOA2,and NCOA3,is critical in regulating gene expression through interactions with nuclear receptors and other transcription factors.These coactivators are implicated in various cancers,but their comprehensive roles across different cancer types remain poorly understood.Methods:We performed a pan-cancer bioinformatics analysis using data from The Cancer Genome Atlas and the Genotype-Tissue Expression project.We assessed the differential expression,copy number variations,mutations,methylation status,tumor mutation burden,microsatellite instability,and immune cell infiltration associated with NCOA family members across various cancers.Differential expression analysis was conducted using the DESeq2 package.Methylation data were analyzed using the ChAMP package,and immune cell infiltration was estimated using the CIBERSORT algorithm.Results:NCOA1 and NCOA2 were predominantly downregulated in multiple cancers,suggesting potential tumor suppressor roles,whereas NCOA3 was largely upregulated,indicating a consistent oncogenic function.These expression patterns significantly correlated with patient prognosis.Frequent copy number variations,particularly gains,and high mutation rates were observed in NCOA2.NCOA3 demonstrated consistent hypomethylation in tumors,which was associated with increased gene expression.Significant correlations were found between NCOA expression and tumor mutation burden,microsatellite instability,and immune cell infiltration,indicating their involvement in genomic instability and immune modulation.Conclusion:This comprehensive analysis reveals significant alterations in the expression,genomic,and epigenetic profiles of NCOA family members across various cancers.The findings highlight the multifaceted roles of NCOA1,NCOA2,and NCOA3 in tumorigenesis and their potential as biomarkers and therapeutic targets.Future research should focus on elucidating the mechanisms underlying the associations between NCOA expression,genomic alterations,and immune modulation to develop targeted cancer therapies. 展开更多
关键词 NCOA family immune modulation bioinformatics analysis cancer biomarkers
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Direct measurement and optimization of the polarization-dependent modulation depth in super-resolution structured illumination microscopy
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作者 Linbo Wang Simin Li +4 位作者 Xiaohu Chen Xin Jin Jie Zhang Hui Li Gang Wen 《Journal of Innovative Optical Health Sciences》 2025年第4期121-131,共11页
Maintaining the s-polarization state of laser beams is important to achieve high modulation depth in a laser-interference-based super-resolution structured illumination microscope(SR-SIM).However,the imperfect optical... Maintaining the s-polarization state of laser beams is important to achieve high modulation depth in a laser-interference-based super-resolution structured illumination microscope(SR-SIM).However,the imperfect optical components can depolarize the laser beams hence degenerating the modulation depth.Here,we first presented a direct measurement method designed to estimate the modulation depth more precisely by shifting illumination patterns with equal phase steps.This measurement method greatly reduces the dependence of modulation depths on the samples,and then developed a polarization optimization method to achieve high modulation depth at all orientations by actively and quantitatively compensating for the additional phase difference using a combination of waveplate and a liquid crystal variable retarder(LCVR).Experimental results demonstrate that our method can achieve illumination patterns with modulation depth higher than 0.94 at three orientations with only one LCVR voltage,which enables isotropic resolution improvement. 展开更多
关键词 Structured illumination microscopy DEPOLARIZATION modulation depth phase compensation
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Sustainable Carbon-Based Catalyst Materials Derived From Lignocellulosic Biomass for Energy Storage and Conversion:Atomic Modulation and Properties Improvement
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作者 Wei Li Ying Xu +4 位作者 Guanhua Wang Ting Xu Kui Wang Shangru Zhai Chuanling Si 《Carbon Energy》 2025年第5期55-100,共46页
Carbon electrocatalyst materials based on lignocellulosic biomass with multi-components,various dimensions,high carbon content,and hierarchical morphology structures have gained great popularity in electrocatalytic ap... Carbon electrocatalyst materials based on lignocellulosic biomass with multi-components,various dimensions,high carbon content,and hierarchical morphology structures have gained great popularity in electrocatalytic applications recently.Due to the catalytic deficiency of neutral carbon atoms,the usage of single lignocellulosic-based carbon materials in electrocatalysis involving energy storage and conversion presents unsatisfactory applicability.However,atomic-level modulation of lignocellulose-based carbon materials can optimize the electronic structures,charge separation,transfer processes,and so forth,which results in substantially enhanced electrocatalytic performance of carbon-based catalysts.This paper reviews the recent advances in the rational design of lignocellulosic-based carbon materials as electrocatalysts from an atomic-level perspective,such as self/external heteroatom doping and metal modification.Then,through systematic discussion of the design principles and reaction mechanisms of the catalysts,the applications of the prepared lignocellulosic-based catalysts in rechargeable batteries and electrocatalysis are reviewed.Finally,the challenges in improving the catalytic performance of lignocellulosic-based carbon materials as electrocatalysts and the prospects in diverse applications are reviewed.This review contributes to the synthesis strategy of lignocellulose-based carbon electrocatalysts via atomic-level modulation,which in turn promotes the lignocellulose valorization for energy storage and conversion. 展开更多
关键词 atomic modulation carbon materials ELECTROCATALYSIS lignocellulosic biomass rechargeable batteries
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Large-angle stimulated Raman scattering induced by transverse density modulation
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作者 Z.M.Huang Qing Wang +12 位作者 R.J.Cheng X.X.Li S.Y.Lv D.J.Liu Z.Y.Xu S.T.Zhang Z.J.Chen Qiang Wang C.Z.Xiao Z.J.Liu L.H.Cao C.Y.Zheng X.T.He 《Matter and Radiation at Extremes》 2025年第5期64-72,共9页
Large-angle stimulated Raman scattering(LA-SRS)in a longitudinally inhomogeneous plasma with a transverse density modulation is studied using a three-wave coupled model and numerical simulations.The simulations show t... Large-angle stimulated Raman scattering(LA-SRS)in a longitudinally inhomogeneous plasma with a transverse density modulation is studied using a three-wave coupled model and numerical simulations.The simulations show that the scattering angle of SRS in a longitudinally inhomogeneous plasma can be significantly affected by transverse density modulation.Under transverse density modulation conditions,the laser focuses into underdense regions,owing to the transversely modulated refractive index.The angle of LA-SRS,neither a purely 90° angle side scattering nor purely backscattering,is almost consistent with the specific angle at which the density inhomogeneity vanishes.In modulated plasmas,the nonuniform distribution of laser intensity shifts the regions of scattering and gain compared with those in uniform plasmas,ultimately affecting the laser transmission.SRS is suppressed in weakly modulated regimes,whereas it is enhanced under strong modulation conditions,and a theoretical criterion distinguishing between strong and weak modulation is established. 展开更多
关键词 longitudinally inhomogeneous plasma transverse density modulation numerical simulationsthe transversely modulated refractive indexthe large angle stimulated Raman scattering three wave coupled model transverse density modulationunder
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Research onπ/4QPSK Modulation Communication Transmission System and FPGA Implementation
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作者 Yuhui Chu Yunjie Yuan +2 位作者 Xiaolei Cai Yanyan Wang Peijie Yin 《Journal of Electronic Research and Application》 2025年第2期12-17,共6页
This paper examines theπ/4QPSK modulation communication transmission system,analyzing the performance advantages and disadvantages ofπ/4QPSK in comparison to QPSK.It also presents a comprehensive FPGA implementation... This paper examines theπ/4QPSK modulation communication transmission system,analyzing the performance advantages and disadvantages ofπ/4QPSK in comparison to QPSK.It also presents a comprehensive FPGA implementation scheme for a modulation communication transmission system,integrating RS channel coding,framing,frequency conversion,and other modules.This design is based on practical research and development requirements.The Xilinx Spartan6 chip board was used for board-level verification.Theπ/4QPSK modulated signal was transmitted via D/A conversion and radio frequency,with the transmitted waveform was looped back for reception.After A/D processing,the correctness of the designed modulation transmission scheme was verified. 展开更多
关键词 π/4QPSK modulation FPGA
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Dynamic hybrid visual-thermal multimodal perception neuromorphic devices based on defect modulation of electrospun nanofibers
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作者 Shengkai Wen Yanan Liu +3 位作者 Yi Li Liang Xie Jun Li Jianhua Zhang 《International Journal of Extreme Manufacturing》 2025年第2期749-761,共13页
Neuromorphic devices,inspired by the intricate architecture of the human brain,have garnered recognition for their prodigious computational speed and sophisticated parallel computing capabilities.Vision,the primary mo... Neuromorphic devices,inspired by the intricate architecture of the human brain,have garnered recognition for their prodigious computational speed and sophisticated parallel computing capabilities.Vision,the primary mode of external information acquisition in living organisms,has garnered substantial scholarly interest.Notwithstanding numerous studies simulating the retina through optical synapses,their applications remain circumscribed to single-mode perception.Moreover,the pivotal role of temperature,a fundamental regulator of biological activities,has regrettably been relegated to the periphery.To address these limitations,we proffer a neuromorphic device endowed with multimodal perception,grounded in the principles of light-modulated semiconductors.This device seamlessly accomplishes dynamic hybrid visual and thermal multimodal perception,featuring temperature-dependent paired pulse facilitation properties and adaptive storage.Crucially,our meticulous examination of transfer curves,capacitance–voltage(C–V)tests,and noise measurements provides insights into interface and bulk defects,elucidating the physical mechanisms underlying adaptive storage and other functionalities.Additionally,the device demonstrates a variety of synaptic functionalities,including filtering properties,Ebbinghaus curves,and memory applications in image recognition.Surprisingly,the digital recognition rate achieves a remarkable value of 98.8%. 展开更多
关键词 neuromorphic devices electrospinning defect modulation dynamic hybrid multimodal perception adaptive storage
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Sequential-gated transformable nanoprodrug potentiates antitumor immunity through TME modulation and STING activation
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作者 Yongjuan Li Rongrong Zhu +5 位作者 Yichen Guo Yayun Wang Rong Ma Kunru Ma Yongxing Zhao Weijing Yang 《Chinese Chemical Letters》 2025年第9期458-465,共8页
Nanomaterials that can sequentially respond to internal and external stimuli,functioning as a sequential gate,have great potential for targeting different aspects of antitumor immunity.Herein,we construct a mannose-mo... Nanomaterials that can sequentially respond to internal and external stimuli,functioning as a sequential gate,have great potential for targeting different aspects of antitumor immunity.Herein,we construct a mannose-modified,pH and reactive oxygen species(ROS) sequential-responsive,transformable dualimmunofunction nanoprodrug(MpRTNP).This nanoprodrug encapsulates a transforming growth factor-β(TGF-β) receptor inhibitor SD-208(MpRTNP@SD),to simultaneously alleviate the immunosuppressive effects of TGF-β and tumor-associated macrophages(TAMs).In the weakly acidic tumor microenvironment(TME),the vesicle-micelle morphology transformation occurs owing to the protonation of PC7A,which is accompanied by SD-208 release to inhibit cancer-associated fibroblasts and regulatory T cells.The transformed micelles then target TAMs via mannose receptor-media ted endocytosis.Upon laser irradiation,the thioketal linker is cleaved,releasing conjugated chlorin e6 and generating ROS,which facilitates TAM polarization.The PC7A^(+) segment activates the stimulator of the interferon gene in TAMs with elevated phosphorylation of TANK binding kinase 1 and interferon regulatory factor 3,and type I interferon secretion.MpRTNP@SD displays superior abscopal effects and robust antitumor immunity,as evidenced by increased CD8^(+)/CD4^(+) T cell infiltration and reduced regulatory T cell(Treg) ratios.Mouse survival time is prolonged after combination with the CD47 antibody.This study provides a novel strategy for potent antitumor immunotherapy through pH and ROS sequential-gated spatiotemporal regulation of the TME. 展开更多
关键词 Drug delivery Stimulus-responsive nanoprodrug Tumor microenvironment modulation STING activation Cancer immunotherapy
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Scutellaria barbata D.Don extracts alleviate SARS-CoV-2 induced acute lung injury by inhibiting virus replication and bi-directional immune modulation
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作者 Yan Ran Zinuo Chen +4 位作者 Carolina Q.Sacramento Lingyuan Fan Qinghua Cui Lijun Rong Ruikun Du 《Virologica Sinica》 2025年第3期430-438,共9页
The emergence of SARS-CoV-2 variants and drug-resistant mutants emphasizes the urgent need to develop novel antiviral agents.In the present study,we examined the therapeutic effect of the Chinese medicinal herb,Scutel... The emergence of SARS-CoV-2 variants and drug-resistant mutants emphasizes the urgent need to develop novel antiviral agents.In the present study,we examined the therapeutic effect of the Chinese medicinal herb,Scutellaria barbata D.Don(SBD),against SARS-CoV-2 infection both in vitro and in vivo.Using a viral replicon particle(VRP)-based mouse model of SARS-CoV-2 infection,our study revealed that SBD extracts can reduce viral load in mouse lungs and alleviate the viral induced pneumonia.In vitro antiviral determination further validated the direct acting antiviral efficacy of SBD extracts against SARS-CoV-2 replication.Mechanistic studies demonstrated that SBD can act against SARS-CoV2 replication by targeting both 3-chymotrypsin-like and papain-like cysteine proteases,via a combination of multiple active constituents.Moreover,SBD can modulate the host inflammation response in a bi-directional manner,which also contribute to the mitigation of viral induced acute lung injury.In summary,our study provides SBD as a promising therapeutic agent to combat SARS-CoV-2 infections that merit further development. 展开更多
关键词 SARS-CoV-2 Scutellaria barbata D.Don ANTIVIRAL Bi-directional immune modulation
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Improved Spectral Amplitude Modulation Based on Sparse Feature Adaptive Convolution for Variable Speed Fault Diagnosis of Bearing
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作者 Jiawei Lin Changkun Han +3 位作者 Wei Lu Liuyang Song Peng Chen Huaqing Wang 《Journal of Dynamics, Monitoring and Diagnostics》 2025年第1期31-43,共13页
Difficulty in extracting nonlinear sparse impulse features due to variable speed conditions and redundant noise interference leads to challenges in diagnosing variable speed faults.Therefore,an improved spectral amplit... Difficulty in extracting nonlinear sparse impulse features due to variable speed conditions and redundant noise interference leads to challenges in diagnosing variable speed faults.Therefore,an improved spectral amplitude modulation(ISAM)based on sparse feature adaptive convolution(SFAC)is proposed to enhance the fault features under variable speed conditions.First,an optimal bi-damped wavelet construction method is proposed to learn signal impulse features,which selects the optimal bi-damped wavelet parameters with correlation criterion and particle swarm optimization.Second,a convolutional basis pursuit denoising model based on an optimal bi-damped wavelet is proposed for resolving sparse impulses.A model regularization parameter selection method based on weighted fault characteristic amplitude ratio assistance is proposed.Then,an ISAM method based on kurtosis threshold is proposed to further enhance the fault information of sparse signal.Finally,the type of variable speed faults is determined by order spectrum analysis.Various experimental results,such as spectral amplitude modulation and Morlet wavelet matching,verify the effectiveness and advantages of the ISAM-SFAC method. 展开更多
关键词 bearing fault diagnosis feature enhancement sparse representation spectral amplitude modulation variable speed
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A Novel Secrecy Enhancing Scheme for Spatial Modulation in the Presence of Imperfect CSI
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作者 Shang Pingping Chen Junqi +4 位作者 Tao Zhuofan Xie Longhui Wan Xiangkui Guan Liang Qin Jiangyi 《China Communications》 2025年第6期291-299,共9页
Based on the objective reality of channel estimation error,this paper introduces a novel artificial noise(AN)aided spatial modulation(SM)secrecyenhancing scheme under imperfect channel state information(CSI).In the pr... Based on the objective reality of channel estimation error,this paper introduces a novel artificial noise(AN)aided spatial modulation(SM)secrecyenhancing scheme under imperfect channel state information(CSI).In the proposed scheme,SM is used to activate one antenna from the transmit antennas,and the information symbols will be transmitted with the designed AN at each timeslot.By utilizing the legitimate channel’s imperfect CSI,AN is generated across two adjacent timeslots.Because the CSI is known at the legitimate receiver,then it can perfectly cancel the AN.However,the eavesdropper knows nothing of the legitimate channel’s CSI,so it can not recover any useful information from the AN.At the receiver,a new detection scheme that detects across two adjacent timeslots is also proposed.With imperfect CSI,the secrecy rate of the proposed scheme is derived over Rayleigh fading channels in order to investigate the performance.Moreover,based on the secrecy performance analysis,the lower bound of the ergodic secrecy rate(ESR),the corresponding closed form of the lower bound,and the approximated expression are also derived.The simulation results verified in this paper prove that the proposed scheme with imperfect CSI can achieve satisfactory performance. 展开更多
关键词 artificial noise ergodic secrecy rate imperfect channel state information physical layer security spatial modulation
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The promise of synthetic bacteria in cancer immunotherapy:Revitalizing tumor immunity via IL-10R modulation
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作者 Jiahe Li Allen P.Liu 《hLife》 2025年第10期459-461,共3页
The immune system is the body's main cancer surveillance system.Unlike surgery,radiation,and chemotherapy,which are typically nonspecific,cancer immunotherapy holds tremendous promise as it harnesses the high spec... The immune system is the body's main cancer surveillance system.Unlike surgery,radiation,and chemotherapy,which are typically nonspecific,cancer immunotherapy holds tremendous promise as it harnesses the high specificity of a person's immune system to kill cancer cells selectively.This promising approach includes checkpoint inhibitors,chimeric antigen receptor (CAR)-T cell therapy,cancer vaccines,cytokines,and monoclonal antibodies,among others.Cancer immunotherapy has progressed tremendously,resulting from basic science discoveries in the molecular and cellular biology of T cells. 展开更多
关键词 IL R modulation checkpoint inhibitorschimeric cancer immunotherapy monoclonal antibodiesamong immune system tumor immunity synthetic bacteria cancer surveillance
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A Biomimetic Stress Field Modulation Strategy Inspired by Scorpion Compound Slit Sensilla Enabled High-Accuracy and Low-Power Positioning Sensor for Identifying the Load Incident Angles
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作者 Junqiu Zhang Yu Chen +11 位作者 Haoran Li Jiqi Gao Xiangbo Gu Jiachao Wu Xiaojing Qin Kejun Wang Bin Zhu Daobing Chen Tao Sun Jianhua Fan Zhiwu Han Luquan Ren 《Journal of Bionic Engineering》 2025年第2期727-738,共12页
Numerous arthropods evolve and optimize sensory systems, enabling them to effectively adapt complex and competitive habitats. Typically, scorpions can precisely perceive the prey location with the lowest metabolic rat... Numerous arthropods evolve and optimize sensory systems, enabling them to effectively adapt complex and competitive habitats. Typically, scorpions can precisely perceive the prey location with the lowest metabolic rate among invertebrates. This biological phenomenon contrasts sharply with engineered systems, which generally associates high accuracy with substantial energy consumption. Inspired by the Scorpion Compound Slit Sensilla (SCSS) with a stress field modulation strategy, a bionic positioning sensor with superior precision and minimal power consumption is developed for the first time, which utilizes the particular Minimum Positioning Units (MPUs) to efficiently locate vibration signals. The single MPU of the SCSS can recognize the direction of collinear loads by regulating the stress field distribution and further, the coupling action of three MPUs can realize all-angle vibration monitoring in plane. Experiments demonstrate that the bionic positioning sensor achieves 1.43 degrees of angle-error-free accuracy without additional energy supply. As a proof of concept, two bionic positioning sensors and machine learning algorithm are integrated to provide centimeter (cm)-accuracy target localization, ideally suited for the man-machine interaction. The novel design offers a new mechanism for the design of traditional positioning devices, improving precision and efficiency in both the meta-universe and real-world Internet-connected systems. 展开更多
关键词 Scorpion Compound Slit Sensilla(SCSS) Vibration Source Stress Field modulation Strategy High-accuracy and low-power Positioning Sensor Minimum Positioning Unit(MPU)
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基于KOA-TCN-LSTM检测算法的STBC-OOFDMIM系统
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作者 王惠琴 张红彦 +1 位作者 王真 唐崎涵 《华中科技大学学报(自然科学版)》 北大核心 2025年第9期176-185,共10页
针对光正交频分复用索引调制(OOFDM-IM)系统在激活子载波较多时存在误码性能不理想的问题,提出了一种基于空时分组编码(STBC)的STBC-OOFDM-IM方案.该方案通过空间分集技术将信息符号在多个发射天线间进行正交编码,结合索引调制的频谱效... 针对光正交频分复用索引调制(OOFDM-IM)系统在激活子载波较多时存在误码性能不理想的问题,提出了一种基于空时分组编码(STBC)的STBC-OOFDM-IM方案.该方案通过空间分集技术将信息符号在多个发射天线间进行正交编码,结合索引调制的频谱效率优势,实现了空频联合分集增益.理论分析表明:编码后系统在保持传输速率不变的同时,可获得显著的误码性能改善.进一步提出了基于开普勒优化的级联型时间卷积网络与长短期记忆网络(KOA-TCN-LSTM)检测算法.该算法将TCN的局部时序特征提取能力与LSTM的长期依赖建模能力相结合,通过端到端学习直接建立接收信号到发射信号的映射关系.此外,引入KOA优化算法对网络超参数进行全局寻优,有效解决了传统梯度下降易陷入局部最优的问题.仿真结果表明:在弱湍流条件下,当误码率为1×10^(-4)时,(2,1,2)系统的信噪比在编码后改善了约3.8 dB.所提检测算法在获得近似最大似然性能的同时,计算复杂度和时间开销有效降低,这为大气激光通信系统的实用化提供了有效的技术途径. 展开更多
关键词 无线光通信 光正交频分复用索引调制(OOFDM-im) 正交空时编码 TCN-LSTM网络 开普勒优化算法(KOA)
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Index modulation aided generalized space-time block coding:A unified MIMO framework 被引量:1
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作者 Zhiqin Wang Hui Liu +3 位作者 Lixia Xiao Liuke Li Guochao Song Tao Jiang 《Digital Communications and Networks》 CSCD 2024年第5期1459-1470,共12页
In this paper,Index Modulation(IM)aided Generalized Space-Time Block Coding(GSTBC)is proposed,which intrinsically exploits the benefits of IM concept,diversity gain and spatial multiplexing gain.Specifically,the infor... In this paper,Index Modulation(IM)aided Generalized Space-Time Block Coding(GSTBC)is proposed,which intrinsically exploits the benefits of IM concept,diversity gain and spatial multiplexing gain.Specifically,the information bits are partitioned into U groups,with each being modulated by IM symbols(i.e.Spatial Modulation(SM),Quadrature SM(QSM),etc).Next,the structure of GSTBC is invoked for each K IM symbol,and a total ofμ=U/K GSTBC codes are transmitted via T time slots.A Block Expectation Propagation(B-EP)detector is designed for the proposed IM-GSTBC structure.Moreover,the theoretical Average Bit Error Probability(ABEP)is derived for our IM-GSTBC system,which is confirmed by the simulation results and helpful for performance evaluation.Simulation results show that our proposed IM-GSTBC system is capable of striking an efficient trade-off between spatial multiplexing gain,spatial diversity gain as well as implementation cost imposed for both small-scale and large-scale MIMO antenna configurations. 展开更多
关键词 Index modulation(im) Generalized space time block coding(GSTBC) Spatial multiplexing gain Diversity gain Block expectation propagation(B-EP)
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Design of Protograph LDPC-Coded MIMO-VLC Systems with Generalized Spatial Modulation 被引量:4
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作者 Dai Lin Fang Yi +1 位作者 Guan Yongliang Mohsen Guizani 《China Communications》 SCIE CSCD 2024年第3期118-136,共19页
This paper investigates the bit-interleaved coded generalized spatial modulation(BICGSM) with iterative decoding(BICGSM-ID) for multiple-input multiple-output(MIMO) visible light communications(VLC). In the BICGSM-ID ... This paper investigates the bit-interleaved coded generalized spatial modulation(BICGSM) with iterative decoding(BICGSM-ID) for multiple-input multiple-output(MIMO) visible light communications(VLC). In the BICGSM-ID scheme, the information bits conveyed by the signal-domain(SiD) symbols and the spatial-domain(SpD) light emitting diode(LED)-index patterns are coded by a protograph low-density parity-check(P-LDPC) code. Specifically, we propose a signal-domain symbol expanding and re-allocating(SSER) method for constructing a type of novel generalized spatial modulation(GSM) constellations, referred to as SSERGSM constellations, so as to boost the performance of the BICGSM-ID MIMO-VLC systems.Moreover, by applying a modified PEXIT(MPEXIT) algorithm, we further design a family of rate-compatible P-LDPC codes, referred to as enhanced accumulate-repeat-accumulate(EARA) codes,which possess both excellent decoding thresholds and linear-minimum-distance-growth property. Both analysis and simulation results illustrate that the proposed SSERGSM constellations and P-LDPC codes can remarkably improve the convergence and decoding performance of MIMO-VLC systems. Therefore, the proposed P-LDPC-coded SSERGSM-mapped BICGSMID configuration is envisioned as a promising transmission solution to satisfy the high-throughput requirement of MIMO-VLC applications. 展开更多
关键词 bit-interleaved coded modulation generalized spatial modulation multiple-input multipleoutput protograph LDPC codes visible light communication
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韭菜子不同炮制品特异性气味的GC-IMS比较 被引量:4
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作者 周芃 郭小红 +3 位作者 李杰 陈娟 赵迪加 吴文辉 《中华中医药学刊》 北大核心 2025年第5期61-65,I0018-I0021,共9页
目的对比分析韭菜子生品、酒炙品、盐炙品、醋炙品、清炒品、盐酒共炙品以及蒸熟品等不同炮制方法下特异性气味的差异,建立一种可从气味上区分韭菜子不同炮制品的方法,并为进一步研究韭菜子的炮制化学转化提供参考。方法采用气相色谱—... 目的对比分析韭菜子生品、酒炙品、盐炙品、醋炙品、清炒品、盐酒共炙品以及蒸熟品等不同炮制方法下特异性气味的差异,建立一种可从气味上区分韭菜子不同炮制品的方法,并为进一步研究韭菜子的炮制化学转化提供参考。方法采用气相色谱—离子迁移质谱(Gas chromatography-ion migration mass spectrometry,GC-IMS)技术对韭菜子不同炮制品的挥发性有机物进行检测,并结合VOCal、Reporter、Gallery Plot、Dynamic PCA等软件对GC-IMS谱图进行差异分析、指纹分析、动态主成分分析、相似度分析以及差异物质的定性分析。结果GC-IMS图谱的差异分析显示不同炮制方法下的韭菜子特异性气味成分存在显著差异,明确定性的差异物有54种。其中,香叶醇(Geraniol)、乙酰甲醇(1-hydroxy-2-propanone)、正戊醇(1-pentanol)、2-甲基丙醇(2-Methylpropanol)、烯丙基硫醚(diallyl sulfide)、3-甲基-3-丁烯-1-醇(Methyl-3-but-3-en-1-ol)、乙醇(Ethanol)、丙酸(Propanoic acid)、2-乙酰呋喃(2-acetylfuran)、2,5-二甲基呋喃(2,5-Dimethylfuran)、乙酸乙酯(ethyl acetate)、二烯丙基二硫M(Diallyl disulfide M)、正戊基呋喃(2-Pentylfuran)、己酸M(Hexanoic acid M)、己酸乙酯(Ethyl hexanoate)可作为韭菜子生品的特异性气味的特征挥发物质;2-羟基丙酸乙酯(ethyl 2-hydroxypropanoate)和β-罗勒烯(beta-Ocimene)可作为酒炙或盐酒共炙等辅料为酒的韭菜子炮制品的特异性气味的特征挥发物质;戊醛(pentanal)可作为醋炙韭菜子的特异性气味的特征挥发物质;呋喃甲醇(Furfuryl alcohol)、3-羟基-2-丁酮(3-hydroxy-2-butanone)、丁内酯(Butyrolactone)和芳樟醇(Linalool)可作为蒸熟韭菜子的特异性气味的特征挥发物质;辛醇(Octanol)可作为清炒韭菜子的特异性气味的特征挥发物质。PCA结果显示各组样品分离度良好,且具有相同辅料的样品相似度更大。结论韭菜子经不同方法炮制后其特异性气味成分存在明显差异,GC-IMS技术可作为一种区别韭菜子不同炮制品特异性气味的方法,并为进一步研究韭菜子的炮制转化提供参考。 展开更多
关键词 韭菜子 炮制 气相色谱—离子迁移质谱 特异性气味
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VMAT与IMRT治疗局部晚期非小细胞肺癌的疗效及剂量学比较
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作者 余杰 华松 +2 位作者 刘瀚文 杨峥 贾彦召 《实用癌症杂志》 2025年第12期2000-2004,共5页
目的探讨局部晚期非小细胞肺癌(NSCLC)患者治疗中应用容积旋转调强放疗(VMAT)与适形调强放疗(IMRT)的疗效及计量学差异。方法采用回顾性研究,选取2022年5月至2024年5月接受同步放化疗的150例局部晚期NSCLC患者,患者均接受顺铂+依托泊苷... 目的探讨局部晚期非小细胞肺癌(NSCLC)患者治疗中应用容积旋转调强放疗(VMAT)与适形调强放疗(IMRT)的疗效及计量学差异。方法采用回顾性研究,选取2022年5月至2024年5月接受同步放化疗的150例局部晚期NSCLC患者,患者均接受顺铂+依托泊苷化疗方案,并依据放疗技术不同分为IMRT组(n=77)和VMAT组(n=73),IMRT组应用IMRT,VMAT组应用VMAT。比较2组临床疗效、PTV和危及器官剂量学参数以及放射性损伤发生情况。结果IMRT组治疗总有效率(48.05%)与VMAT组总有效率(58.90%)比较,差异无统计学意义(P>0.05)。IMRT组适形度指数(CI)及各个靶区剂量均低于VMAT组,均匀性指数(HI)高于VMAT组,差异有统计学意义(P<0.05);IMRT组心脏、肺、食管及脊髓照射剂量均高于VMAT组,差异有统计学意义(P<0.05)。VMAT组放射性损伤总发生率(6.85%)显著低于IMRT组(18.18%),差异有统计学意义(P<0.05)。结论对局部晚期NSCLC患者应用IMRT或VMAT技术进行放疗的临床效果相当,但与IMRT相比,VMAT技术可以有效提高靶区适形度和均匀性,且可在提高靶区照射剂量的同时减少危及器官受照射剂量,降低放射性损伤的发生风险。 展开更多
关键词 非小细胞肺癌 局部晚期 适形调强放疗 容积旋转调强放疗 剂量
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High photoelectric conversion efficiency and fast relaxation time of FA_(0.4)MA_(0.6)PbI_(3) applied in ultrafast modulation of terahertz waves 被引量:2
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作者 Zhibo Xu Ying Zeng +5 位作者 Xinran Zhao Xiaoyin Chen Aoyu Fan Furi Ling Jiang Li Jianquan Yao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期299-305,共7页
Active control of terahertz(THz)waves is attracting tremendous attentions in terahertz communications and active photonic devices.Perovskite,due to its excellent photoelectric conversion performance and simple manufac... Active control of terahertz(THz)waves is attracting tremendous attentions in terahertz communications and active photonic devices.Perovskite,due to its excellent photoelectric conversion performance and simple manufacturing process,has emerged as a promising candidate for optoelectronic applications.However,the exploration of perovskites in optically controlled THz modulators is still limited.In this work,the photoelectric properties and carrier dynamics of FA_(0.4)MA_(0.6)PbI_(3)perovskite films were investigated by optical pumped terahertz probe(OPTP)system.The ultrafast carrier dynamics reveal that FA_(0.4)MA_(0.6)PbI_(3)thin film exhibits rapid switching and relaxation time within picosecond level,suggesting that FA_(0.4)MA_(0.6)PbI_(3)is an ideal candidate for active THz devices with ultrafast response.Furthermore,as a proof of concept,a FA_(0.4)MA_(0.6)PbI_(3)-based metadevice with integrating plasma-induced transparency(PIT)effect was fabricated to achieve ultrafast modulation of THz wave.The experimental results demonstrated that the switching time of FA_(0.4)MA_(0.6)PbI_(3)-based THz modulator is near to 3.5 ps,and the threshold of optical pump is as low as 12.7μJ cm^(-2).The simulation results attribute the mechanism of ultrafast THz modulation to photo-induced free carriers in the FA_(0.4)MA_(0.6)PbI_(3)layer,which progressively shorten the capacitive gap of PIT resonator.This study not only illuminates the potential of FA_(0.4)MA_(0.6)PbI_(3)in THz modulation,but also contributes to the field of ultrafast photonic devices. 展开更多
关键词 Terahertz modulation Perovskites METAMATERIALS Plasmon-induced transparency
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