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Multi-frequency formation mechanism and modulation strategy of self-priming enhanced submerged pulsed waterjet 被引量:1
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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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5G/IMS跨省网络冲突治理关键技术与实践
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作者 段俊娜 项朝君 +3 位作者 魏利朋 崔静 马淼娜 罗望东 《数字通信世界》 2026年第2期71-73,81,共4页
针对全国性5G/IMS网络在跨省、跨专业协同运维中的AS路径冲突、IP地址冲突等系统性风险,本文提出“全局一致性”理论模型,创立了跨域协同式无损操作法,并构建了跨专业故障快速定界范式。该体系在全国网络运营中成功应用,已预警并化解10... 针对全国性5G/IMS网络在跨省、跨专业协同运维中的AS路径冲突、IP地址冲突等系统性风险,本文提出“全局一致性”理论模型,创立了跨域协同式无损操作法,并构建了跨专业故障快速定界范式。该体系在全国网络运营中成功应用,已预警并化解10余起重大潜在故障,实现重大操作“零事故”,故障平均定位时间从小时级降至分钟级。 展开更多
关键词 5G/imS高可用性 跨域网络 冲突治理 故障定界
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GC-IMS结合多元统计学比较不同产区市售酱香型白酒挥发性风味成分
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作者 冯雪莹 倪慧 +3 位作者 侯强川 叶明波 郭壮 王玉荣 《中国酿造》 北大核心 2026年第1期282-287,共6页
该研究将4个产自茅台镇和4个产自其他地区的市售酱香型白酒作为研究对象,采用气相色谱-离子迁移谱(GC-IMS)技术结合多元统计学方法,比较分析了不同产区市售酱香型白酒挥发性风味成分的差异。结果表明,8个白酒样品中共检出51种挥发性风... 该研究将4个产自茅台镇和4个产自其他地区的市售酱香型白酒作为研究对象,采用气相色谱-离子迁移谱(GC-IMS)技术结合多元统计学方法,比较分析了不同产区市售酱香型白酒挥发性风味成分的差异。结果表明,8个白酒样品中共检出51种挥发性风味成分,包括酯类24种、醇类9种、醛类10种和酮类8种。主成分分析(PCA)结果表明,茅台镇和其他产区酱香型白酒挥发性风味成分存在差异。基于相对气味活度值(ROAV)共筛选出6种关键挥发性风味化合物(ROAV>1),其中,对茅台镇酱香型白酒香气贡献更突出的为异戊酸乙酯、辛酸乙酯和乙酸异戊酯,ROAV分别为82.25、5.56、1.52,对其他产区酱香型白酒香气贡献更突出的为己酸乙酯、戊酸乙酯和丁酸乙酯,ROAV分别为33.19、32.55、10.48。 展开更多
关键词 酱香型白酒 茅台镇和其他地区 气相色谱-离子迁移谱 多元统计学分析 关键差异挥发性风味化合物
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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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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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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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基于GC-IMS分析不同精炼程度山茶油风味差异的研究
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作者 黄泽宇 曾慧琳 +2 位作者 马思婷 吉贵林 黎冬明 《粮食与油脂》 北大核心 2026年第2期53-57,共5页
为探究精炼工艺对山茶油风味物质的影响,采用气相色谱-离子迁移谱(GC-IMS)技术对毛油、脱胶油、脱色油及成品油中的挥发性成分进行检测。结果表明:在不同精炼程度的山茶油中共鉴定出68种挥发性物质,包括醛类20种、酮类13种、醇类12种、... 为探究精炼工艺对山茶油风味物质的影响,采用气相色谱-离子迁移谱(GC-IMS)技术对毛油、脱胶油、脱色油及成品油中的挥发性成分进行检测。结果表明:在不同精炼程度的山茶油中共鉴定出68种挥发性物质,包括醛类20种、酮类13种、醇类12种、酯类7种、酸类5种、杂环类6种及其他类5种。醛类为山茶油主要风味成分,随着精炼的进行,青草香型醛类增加,而脂肪香型醛类减少。主成分分析(PCA)显示,成品油与其他样品在风味上差异较大,表明脱色之后的精炼工序对风味具有较大的影响。研究结果可为优化山茶油适度精炼和保留特征风味提供理论依据。 展开更多
关键词 山茶油 气相色谱-离子迁移谱 精炼工艺 挥发性成分 风味物质
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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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基于iMES和复杂连线设备的图形前处理控制单元设计方法
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作者 周进群 胡忠华 崔兴强 《机电工程技术》 2026年第4期124-131,共8页
如何实现PCB制造行业智能化、数字化转型升级,设计出有效可靠的控制单元,是一个亟待解决的问题,为此,以PCB制造的内层图形前处理多种类型连线设备为研究对象,提出了图形前处理控制单元系统。基于需求分析,引出iMES智能配方功能及设计,... 如何实现PCB制造行业智能化、数字化转型升级,设计出有效可靠的控制单元,是一个亟待解决的问题,为此,以PCB制造的内层图形前处理多种类型连线设备为研究对象,提出了图形前处理控制单元系统。基于需求分析,引出iMES智能配方功能及设计,实现配方精确和高效。以自动化转运产品和多连线设备数据实现采集为目标,对控制单元层的设备硬件布局作优化设计,提出了单元层的控制结构、不同类型设备的数据采集接口及自动物流接口设计方法。以实现多种连线设备配方下发准确为要求,设计了配方下发逻辑流程。通过内层前处理控制单元系统案例应用,实现了关键参数自动下发和采集,解决了面临的主要问题,提高生产效率26%。设计方法可应用于PCB制造的其他工序控制单元,促进PCB制造转型升级。 展开更多
关键词 imES 连线设备 控制单元 图形前处理
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基于GC-IMS对不同花期金银花挥发性成分的对比分析
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作者 吕瑞君 王蓉 高燕 《药学研究》 2026年第2期170-176,共7页
目的明确金银花的挥发性成分并比较不同花期金银花样品的挥发性成分差异。方法采用气相色谱-离子迁移谱联用技术(GC-IMS)对不同发育期金银花样品进行挥发性有机化合物分析,并运用OPLS-DA分析方法筛选代表性差异特征性成分,针对5个品种、... 目的明确金银花的挥发性成分并比较不同花期金银花样品的挥发性成分差异。方法采用气相色谱-离子迁移谱联用技术(GC-IMS)对不同发育期金银花样品进行挥发性有机化合物分析,并运用OPLS-DA分析方法筛选代表性差异特征性成分,针对5个品种、5个不同花期金银花开展系统性研究。结果通过GC-IMS检测出了72种挥发性化合物,银花期和金花期含苯甲醛二聚体等丰富成分,部分成分(如苯甲醛单体、反式-2,4-庚二烯醛单体等)随发育含量渐增。OPLS-DA结果显示不同花期金银花样品区分明显,并筛选出28个差异特征性成分,包括顺-3-己烯醇单体、正己醇单体、顺-3-己烯醇二聚体等。结论首次快速且全面呈现了不同花期、不同品种金银花挥发性成分异同,筛选出的28个挥发性成分可以作为其特征性成分进行区分。 展开更多
关键词 不同花期 金银花 挥发性成分 气相色谱-离子迁移谱联用技术
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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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Peak current reduction in presence of RF phase modulationin the dual RF system
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作者 Jiang Bocheng Zhang Yao Tsai Cheng-Ying 《强激光与粒子束》 北大核心 2026年第1期160-165,共6页
[Background]High harmonic cavities are widely used in electron storage rings to lengthen thebunch,lower the bunch peak current,thereby reducing the IBS effect,enhancing the Touschek lifetime,as well asproviding Landau... [Background]High harmonic cavities are widely used in electron storage rings to lengthen thebunch,lower the bunch peak current,thereby reducing the IBS effect,enhancing the Touschek lifetime,as well asproviding Landau damping,which is particularly important for storage rings operating with ultra-low emittance or atlow beam energy.[Purpose]To further increase the bunch length without additional hardware costs,the phasemodulation in a dual-RF system is considered.[Methods]In this paper,turn-by-turn simulations incorporating randomsynchrotron radiation excitation are conducted,and a brief analysis is presented to explain the bunch lengtheningmechanism.[Results]Simulation results reveal that the peak current can be further reduced,thereby mitigating IBSeffects and enhancing the Touschek lifetime.Although the energy spread increases,which tends to reduce thebrightness of higher-harmonic radiation from the undulator,the brightness of the fundamental harmonic can,in fact,beimproved. 展开更多
关键词 dual high-frequency system phase modulation beam bunch stretching intra-beam scattering
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Impact of Well Thickness on Static and Dynamic Behavior of InGaN Light-emitting Diode with Single Quantum Well
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作者 CHEN Guichu HE Longfei PENG Kun 《发光学报》 北大核心 2026年第2期314-320,共7页
In this paper,we present a circuit model of single-quantum-well InGaN/GaN light-emitting diodes based on the standard rate equations.Two rate equations describe carrier transport processes occurring in sep-arate confi... In this paper,we present a circuit model of single-quantum-well InGaN/GaN light-emitting diodes based on the standard rate equations.Two rate equations describe carrier transport processes occurring in sep-arate confinement heterostructure and quantum well respectively,and the third equation describes the varied photons in quantum well.By using the presented model,impacts of quantum well thickness on the static and dynamic performances are investigated.Simulated results show that LED with 4 nm well exhibits better lightcurrent(L-I)performance,but LED with 3 nm well presents wider 3 dB modulation bandwidth.It reveals that high carrier density in quantum well is detrimental to the static performance,but beneficial to the dynamic performance. 展开更多
关键词 single quantum well rate equations circuit model L-I performance modulation bandwidth
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基于解剖特征的左侧乳腺癌放疗心脏剂量学分析:3D-CRT、IMRT与VMAT技术比较
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作者 郑博雅 任毅 +6 位作者 朱志坚 王加阳 张青 李硕 韩济华 骆红蕾 宋亚颀 《肿瘤学杂志》 2026年第2期134-140,共7页
[目的]比较三维适形放疗(three dimensional-conformal radiotherapy,3D-CRT)、调强适形放疗(intensity-modulated radiotherapy,IMRT)和容积调强放疗(volumetric modulated arc therapy,VMAT)3种技术在乳腺癌术后放疗中的心脏剂量学差... [目的]比较三维适形放疗(three dimensional-conformal radiotherapy,3D-CRT)、调强适形放疗(intensity-modulated radiotherapy,IMRT)和容积调强放疗(volumetric modulated arc therapy,VMAT)3种技术在乳腺癌术后放疗中的心脏剂量学差异,重点评估其对左前降支冠状动脉(left anterior descending coronary artery,LAD)的剂量学影响,为临床优选放疗方案提供依据。[方法]研究共纳入20例左侧乳腺癌保乳术后患者。基于每例患者的CT定位图像,分别制定3D-CRT(切线野技术)、IMRT(7野均分方案)和VMAT(双弧旋转照射)3种放疗计划。评估心脏平均剂量(Dmean)、心脏V20和LAD V40等关键剂量参数,并分析其与计划靶区(planning target volume,PTV)与心脏距离、心脏体积等解剖因素的相关性。[结果]VMAT在心脏保护方面显著优于其他两组(P<0.001):其中VMAT心脏Dmean中位数为3.49 Gy,低于IMRT(3.50 Gy)和3D-CRT(4.56 Gy);心脏V20中位数为1.13%,较IMRT(1.62%)和3D-CRT(4.05%)更低;且LAD V40中位数为0,显著低于3D-CRT的39.49%和IMRT的5.34%(P<0.001)。VMAT组所有病例的LAD V40均满足临床指南要求(达标率100.0%),而3D-CRT和IMRT组达标率仅分别为5.0%和75.0%。相关性分析显示,各计划PTV心脏距离与LAD V40均呈负相关(P<0.05),当距离<6 mm时,3D-CRT的LAD V40超标率达85.0%以上。[结论]VMAT技术可显著降低心脏及LAD的受照剂量,尤其PTV与心脏距离较近时优势更为明显。PTV与心脏距离是影响LAD受照剂量的重要解剖因素,可作为个体化放疗技术选择的参考依据。 展开更多
关键词 乳腺肿瘤 心脏保护 适形放疗 调强适形放疗 容积调强放疗 左前降支冠状动脉 剂量学分析 解剖因素 个体化治疗
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