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基于改进Adam算法的胃肠镜图像分类方法
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作者 孙海静 崔佳琪 +3 位作者 邵一川 赵骞 张乐 李刚 《沈阳大学学报(自然科学版)》 2026年第1期53-60,90,共9页
提出一种针对胃肠镜图像分类任务优化的改进Adam算法。该算法通过引入学习率衰减和自适应梯度正则化,有效提升了模型在胃肠镜图像上的分类性能和收敛速度。学习率衰减根据梯度变化调节学习率,以加快收敛并减少振荡;自适应梯度正则化能... 提出一种针对胃肠镜图像分类任务优化的改进Adam算法。该算法通过引入学习率衰减和自适应梯度正则化,有效提升了模型在胃肠镜图像上的分类性能和收敛速度。学习率衰减根据梯度变化调节学习率,以加快收敛并减少振荡;自适应梯度正则化能够减少过拟合,提高泛化能力。为验证改进后算法的有效性,在公开的Kvasir数据集上进行了实验,取得了67.67%的准确率,与Adam、SGD、AdamW等算法相比有所提高。 展开更多
关键词 深度学习 改进adam算法 学习率衰减 自适应梯度正则化 胃肠镜图像分类
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基于优化Adam算法的GPR全波形反演
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作者 邓欢 曹礼刚 +1 位作者 庞荣 胡俊 《物探化探计算技术》 2026年第1期47-57,共11页
探地雷达(GPR)时间域双参数全波形反演一直受反演精度欠佳、参数相互干扰、计算量巨大以及容易陷入局部极小值等问题困扰。为了应对这些问题,将Adam算法引入了GPR时间域全波形反演。此方法由于无需进行迭代步长的计算,大大降低了内存占... 探地雷达(GPR)时间域双参数全波形反演一直受反演精度欠佳、参数相互干扰、计算量巨大以及容易陷入局部极小值等问题困扰。为了应对这些问题,将Adam算法引入了GPR时间域全波形反演。此方法由于无需进行迭代步长的计算,大大降低了内存占用和计算的复杂程度,进而提升了反演的效率与精度。首先对参数调节因子在反演中所产生的影响展开分析;其次探讨单尺度与多尺度串行反演策略的优势和不足。为了获取适用于全波形反演(FWI)的Adam超参数,对不同的超参数给Adam算法反演效果带来的影响进行了测试,并提出了更契合全波形反演的优化参数,并采用Overthrust模型的合成数据测试。实验结果表明,相较于采用预设参数的Adam算法与L-BFGS算法的全波形反演,优化超参数的Adam算法在收敛速度与反演精度上均展现出优势。最后,针对含脱空病害的公路模型,采用均匀介质为初始模型进行反演,参数优化的Adam算法反演结果仍略微优于L-BFGS算法。 展开更多
关键词 全波形反演 GPR 多尺度 adam 参数优化
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基于AMESim和ADAMS的矿用管路安装车工作臂联合仿真分析
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作者 樊浩 周海 王士伟 《液压气动与密封》 2026年第2期69-75,共7页
矿用管路安装车是一种用于煤矿井下的管道辅助安装设备。为研究管路安装车工作臂在抓举管路过程中液压系统的动态特性,在分析工作臂的工作原理和工作要求的基础上,基于AMESim和ADAMS软件建立工作臂的机液联合仿真分析模型,设定工作臂的... 矿用管路安装车是一种用于煤矿井下的管道辅助安装设备。为研究管路安装车工作臂在抓举管路过程中液压系统的动态特性,在分析工作臂的工作原理和工作要求的基础上,基于AMESim和ADAMS软件建立工作臂的机液联合仿真分析模型,设定工作臂的仿真工况,采用PID位移反馈控制,分析负载敏感控制系统的优势。仿真结果表明:工作臂各液压缸位移响应很好地跟踪PID控制信号,液压系统动态特性变化稳定连续,满足管路安装车工作要求。 展开更多
关键词 矿用管路安装车 液压系统 AMESIM adamS 联合仿真
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基于ADAMS的水田搅浆刀运动仿真和分析
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作者 孙振雨 李会荣 +4 位作者 王盛春 李宁 张迪 董可宏 李正仁 《农机化研究》 北大核心 2026年第4期103-109,共7页
水田搅浆刀作为搅浆机主要工作部件,在水稻春季整地时起到打碎土壤、埋覆秸秆、形成泥浆的作用,其运动状态决定了地块的打浆埋茬质量,开展搅浆刀运动状态的研究对于提高稻田整地质量很有必要。为此,应用SolidWorks软件对搅浆机进行建模... 水田搅浆刀作为搅浆机主要工作部件,在水稻春季整地时起到打碎土壤、埋覆秸秆、形成泥浆的作用,其运动状态决定了地块的打浆埋茬质量,开展搅浆刀运动状态的研究对于提高稻田整地质量很有必要。为此,应用SolidWorks软件对搅浆机进行建模并简化处理,通过ADAMS软件对搅浆刀作业时运动状态进行仿真,间隔0.1 s记录搅浆刀0~1.0 s的11个运动状态。当搅浆机前进速度1.0 m/s、刀辊转速270 r/min、搅浆刀回转半径230 mm时,ADAMS仿真显示搅浆刀的运动轨迹为余摆线,符合相关理论。通过ADAMS软件后处理,对搅浆刀的位移、速度、加速度、角速度和角加速度等曲线进行分析。其中,搅浆刀的速度呈现规律性的波动状态,由4318.96 mm/s开始逐渐降低到最小值2712.03 mm/s,然后逐渐提高到最大值4712.02 mm/s,随后再降低、提高,随时间呈规律性变化,波动周期0.222 s;搅浆刀在0.046 s首次与泥土接触,0.066 s完全切入泥土,0.120 s完全离开泥土,整个过程时长0.074 s。根据搅浆刀ADAMS后处理数据推导出关于时间的速度函数,并据此计算搅浆刀0.1~0.8 s瞬时速度,与后处理结果进行对比,结果显示:误差率分别为0.37%、1.48%、0.59%、0.34%、3.68%、0.63%、7.10%、0.15%,平均误差率1.79%。 展开更多
关键词 水田搅浆机 搅浆刀 adamS软件 运动仿真
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基于ADAMS的水田打浆机侧边齿轮传动系统仿真和分析
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作者 孙振雨 《农机化研究》 北大核心 2026年第2期276-283,292,共9页
水田打浆机是进行稻田春季打浆埋茬的重要整地机具,为确保机具安全,对1JS320型水田打浆机侧边齿轮传动系统进行研究,包括计算齿轮传动效率、查看齿轮接触受力、分析齿轮运动规律;在打浆机额定作业载荷基础上,进行空载荷、半载荷和超载... 水田打浆机是进行稻田春季打浆埋茬的重要整地机具,为确保机具安全,对1JS320型水田打浆机侧边齿轮传动系统进行研究,包括计算齿轮传动效率、查看齿轮接触受力、分析齿轮运动规律;在打浆机额定作业载荷基础上,进行空载荷、半载荷和超载荷作业情况对比分析,为检验打浆机不同作业条件下打浆效率提供数据支撑;同时,阐述了齿轮传动系统实时传动比与对应载荷、特定时间的关系,以及齿轮振动情况。在SolidWorks软件中创建齿轮传动系统模型,应用ADAMS软件进行动力学仿真,在后处理基础上对主要仿真结果进行分析,结果表明:主动轮角速度稳定保持在1620(°)/s附近,载荷越大角速度越平稳;从动轮角速度振荡分布在1757.35(°)/s附近,载荷越大角速度震动越剧烈;不同载荷下,从动轮系统综合传动比0.919,小于理论传动比0.923;4条传动比曲线沿理论传动比直线上下震荡分布,位于直线上部和下部的曲线形状基本一致;齿轮间接触力随从动轮载荷的增加而变大,载荷每增加3930 N,接触力分别增加61.5、52.2 N;齿轮间最大接触力4551.8 N,小于许用应力,可安全使用。 展开更多
关键词 水田打浆机 侧边齿轮传动系统 adamS 仿真分析
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油莎豆收获机振动挖掘装置设计与试验——基于EDEM-ADAMS耦合
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作者 孙奎 裴明昊 +2 位作者 徐向东 戚江涛 宋立新 《农机化研究》 北大核心 2026年第3期40-47,共8页
针对油莎豆收获时机械作业难度大、能耗高等问题,设计了一种旋耕挖掘与振动挖掘相结合的油莎豆振动挖掘装置,对其关键部件进行了结构和参数设计,建立了油莎豆、草和土槽离散元模型,通过EDEM-ADAMS耦合方法对油莎豆挖掘过程进行模拟,以... 针对油莎豆收获时机械作业难度大、能耗高等问题,设计了一种旋耕挖掘与振动挖掘相结合的油莎豆振动挖掘装置,对其关键部件进行了结构和参数设计,建立了油莎豆、草和土槽离散元模型,通过EDEM-ADAMS耦合方法对油莎豆挖掘过程进行模拟,以旋耕刀转速、振动筛振幅和振频为试验因素,以油莎豆输送效率、沙土输送效率、漏沙率和作业功率为试验指标进行正交仿真试验设计,探究各作业参数对挖掘效果的影响。仿真试验表明:当旋耕刀转速为370 r/min、振幅为9 mm、振频为12.5 Hz时,油莎豆输送效率可达97.8%。此条件下田间试验的油莎豆破损率、根—草粉碎率和根—草带土率分别为2.67%、65.51%、59.52%,满足油莎豆收获农艺要求,可为油莎豆振动挖掘装置优化研究提供参考。 展开更多
关键词 油莎豆收获 旋耕挖掘 振动挖掘 破损率 EDEM-adamS耦合 仿真
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A Superimposed Pilot with Transition Band Channel Estimation Scheme for OTFS
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作者 He Xiandeng Shu Kai Yi Yunhui 《China Communications》 2026年第1期107-124,共18页
The orthogonal time frequency space(OTFS)modulation is a novel modulation scheme that can effectively cope with the high Doppler expansion caused by high mobility.Since it modulates data on delay-Doppler(DD)domain and... The orthogonal time frequency space(OTFS)modulation is a novel modulation scheme that can effectively cope with the high Doppler expansion caused by high mobility.Since it modulates data on delay-Doppler(DD)domain and makes full use of the sparse characteristics of DD domain,it has been widely studied to design efficient channel estimation and signal detection schemes.In this paper,we design a novel superimposed pilot pattern with transition band,which replaces the traditional embedded pilot(EP)guard zero-symbols,and perform a two-stage channel estimation.In the first stage,we fully utilize the dispersion characteristics of OTFS signal in DD domain,and use threshold decision to make coarse channel estimation.In the second stage,we use the results of the coarse estimation for iterative signal detection and accurate channel estimation.During the second stage,we make full use of the sparsity of the channel in DD domain,remodel the received signal into the form of sparse channel vector multiplied by channel coefficient matrix,and introduce Doppler index segmentation factor(DISF)to subdivide the Doppler index to solve the problem of fractional Doppler.Simulations reveal that,the scheme proposed in this paper has higher spectral efficiency compared with traditional EP scheme and lower peak-to-average power ratio(PAPR)compared with traditional superimposed pilot scheme. 展开更多
关键词 channel estimation OTFS signal detection superimposed pilot
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Unified physics-informed subspace identification and transformer learning for lithium-ion battery state-of-health estimation
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作者 Yong Li Hao Wang +3 位作者 Chenyang Wang Liye Wang Chenglin Liao Lifang Wang 《Journal of Energy Chemistry》 2026年第1期350-369,I0009,共21页
The growing use of lithium-ion batteries in electric transportation and grid-scale storage systems has intensified the need for accurate and highly generalizable state-of-health(SOH)estimation.Conventional approaches ... The growing use of lithium-ion batteries in electric transportation and grid-scale storage systems has intensified the need for accurate and highly generalizable state-of-health(SOH)estimation.Conventional approaches often suffer from reduced accuracy under dynamically uncertain state-of-charge(SOC)operating ranges and heterogeneous aging stresses.This study presents a unified SOH estimation framework that integrates physics-informed modeling,subspace identification,and Transformer-based learning.A reduced-order model is derived from simplified electrochemical dynamics,providing an interpretable and computationally efficient representation of battery behavior.Subspace identification across a wide SOC and SOH range yields degradation-sensitive features,which the Transformer uses to capture long-range aging dynamics via multi-head self-attention.Experiments on LiFePO4 cells under joint-cell training show consistently accurate SOH estimation,with a maximum error of 1.39%,demonstrating the framework’s effectiveness in decoupling SOC and SOH effects.In cross-cell validation,where training and validation are performed on different cells,the model maintains a maximum error of 2.06%,confirming strong generalization to unseen aging trajectories.Comparative experiments on LiFePO_(4)and public LiCoO_(2)datasets confirm the framework’s cross-chemistry applicability.By extracting low-dimensional,physically interpretable features via subspace identification,the framework significantly reduces training cost while maintaining high SOH estimation accuracy,outperforming conventional data-driven models lacking physical guidance. 展开更多
关键词 Lithium-ion battery Transformer learning Physics-informed modeling Subspace identification State-of-health estimation
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Single broadband source depth estimation using Stokes parameters in shallow water
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作者 Yizheng Wei Chao Sun +1 位作者 Lei Xie Mingyang Li 《Chinese Physics B》 2026年第2期451-460,共10页
Presented in this study is a novel method for estimating the depth of single underwater source in shallow water,utilizing vector sensors.The approach leverages the depth distribution of the broadband Stokes parameters... Presented in this study is a novel method for estimating the depth of single underwater source in shallow water,utilizing vector sensors.The approach leverages the depth distribution of the broadband Stokes parameters to estimate source depth accurately.Unlike traditional matched field processing(MFP)and matched mode processing(MMP),the proposed approach can estimate source depth directly from the data received by sensors without requiring complete environmental information.Firstly,the broadband Stokes parameters(BSP)are established using the normal mode theory.Then the nonstationary phase approximation is used to simplify the theoretical derivation,which is necessary when dealing with broadband integrals.Additionally,range terms of the BSP are eliminated by normalization.By analyzing the depth distribution of the normalized broadband Stokes parameters(NBSP),it is found that the NBSP exhibit extreme values at the source depth,which can be used for source depth estimation.So the proposed depth estimation method is based on searching the peaks of the NBSP.Simulations show that this method is effective in relatively simple shallow water environments.Finally,the effect of source range,frequency bandwidth,sound speed profile(SSP),water depth,and signal-to-noise ratio(SNR)are studied.The findings indicate that the proposed method can accurately estimate the source depth when the SNR is greater than-5 d B and does not need to consider model mismatch issues.Additionally,variations in environmental parameters have minimal impact on estimation accuracy.Compared to MFP,the proposed method requires a higher SNR,but demonstrates superior robustness against fluctuations in environmental parameters. 展开更多
关键词 broadband source depth estimation shallow water POLARIZATION Stokes parameters
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UAV-to-Ground Channel Modeling:(Quasi-)Closed-Form Channel Statistics and Manual Parameter Estimation
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作者 Zeng Linzhou Liao Xuewen +3 位作者 Xie Wenwu Ma Zhangfeng Xiong Baiping Jiang Hao 《China Communications》 2026年第1期47-66,共20页
(Quasi-)closed-form results for the statistical properties of unmanned aerial vehicle(UAV)airto-ground channels are derived for the first time using a novel spatial-vector-based method from a threedimensional(3-D)arbi... (Quasi-)closed-form results for the statistical properties of unmanned aerial vehicle(UAV)airto-ground channels are derived for the first time using a novel spatial-vector-based method from a threedimensional(3-D)arbitrary-elevation one-cylinder model.The derived results include a closed-form expression for the space-time correlation function and some quasi-closed-form ones for the space-Doppler power spectrum density,the level crossing rate,and the average fading duration,which are shown to be the generalizations of those previously obtained from the two-dimensional(2-D)one-ring model and the 3-D low-elevation one-cylinder model for terrestrial mobile-to-mobile channels.The close agreements between the theoretical results and the simulations as well as the measurements validate the utility of the derived channel statistics.Based on the derived expressions,the impacts of some parameters on the channel characteristics are investigated in an effective,efficient,and explicable way,which leads to a general guideline on the manual parameter estimation from the measurement description. 展开更多
关键词 channel characteristics geometry-based stochastic model manual parameter estimation UAV channel modeling
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非小细胞肺癌患者血清SOX11、ProGRP、ADAM12表达与临床病理特征及预后的关系
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作者 徐海亮 申思 杨泽西 《临床肺科杂志》 2026年第3期417-423,共7页
目的探讨非小细胞肺癌(NSCLC)患者血清转录因子性别决定区Y框蛋白11(SOX11)、胃泌素释放肽前体(ProGRP)、去整合素金属蛋白酶12(ADAM12)表达与临床病理特征及预后的关系。方法选取2020年3月至2022年3月本院收治的符合手术治疗指征的134... 目的探讨非小细胞肺癌(NSCLC)患者血清转录因子性别决定区Y框蛋白11(SOX11)、胃泌素释放肽前体(ProGRP)、去整合素金属蛋白酶12(ADAM12)表达与临床病理特征及预后的关系。方法选取2020年3月至2022年3月本院收治的符合手术治疗指征的134例NSCLC患者及134例无肺部疾病的体检者为研究对象,分别纳入NSCLC组和健康组;其中31例患者随访期间发生局部复发或远处转移,纳入复发转移组,其余103例患者术后病情稳定,纳入无复发转移组。采用ELISA法检测血清SOX11、ProGRP、ADAM12水平;采用多因素Logistic回归分析NSCLC患者术后局部复发或远处转移的影响因素;采用ROC曲线评估SOX11、ProGRP、ADAM12对NSCLC患者术后局部复发或远处转移的预测价值。结果NSCLC组血清SOX11、ProGRP和ADAM12水平较健康组显著升高(P<0.05)。SOX11、ProGRP和ADAM12表达与TNM分期有关(P<0.05)。对于血清SOX11、ProGRP、ADAM12水平,ⅢA期NSCLC患者高于Ⅰ~Ⅱ期NSCLC患者,其中接受辅助化疗的Ⅰ~Ⅱ期NSCLC患者低于未接受辅助化疗的Ⅰ~Ⅱ期NSCLC患者(P<0.05)。复发转移组患者处于ⅢA期人数占比高于无复发转移组患者,复发转移组术后血清SOX11、ProGRP、ADAM12水平显著高于术前(P<0.05),无复发转移组术后血清SOX11、ProGRP、ADAM12水平低于术前(P<0.05);与无复发转移组比较,复发转移组术后血清SOX11、ProGRP、ADAM12水平显著升高(P<0.05),ⅢA期及SOX11、ProGRP、ADAM12均为NSCLC患者术后局部复发或远处转移的危险因素(P<0.05)。SOX11、ProGRP、ADAM12联合预测NSCLC患者术后局部复发或远处转移的AUC为0.953(95%CI:0.916~0.989),优于SOX11(Z=2.532,P<0.001)、ProGRP(Z=3.476,P<0.001)、ADAM12(Z=2.680,P<0.001)单一预测的AUC。结论NSCLC患者血清SOX11、ProGRP、ADAM12水平升高,三者与TNM分期密切相关,三者联合预测NSCLC患者术后局部复发或远处转移的价值较高。 展开更多
关键词 非小细胞肺癌 SOX11 PROGRP adam12 临床病理特征 预后
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Enhancing Underwater Monocular Depth Estimation with Lpg-Lap Unet for Target Tracking Mission
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作者 YAO Peng WANG Yalu 《Journal of Ocean University of China》 2026年第1期161-170,共10页
Accurately estimating depth from underwater monocular images is essential for the target tracking task of unmanned underwater vehicles.This work proposes a method based on the Lpg-Lap Unet architecture.First,the Unet ... Accurately estimating depth from underwater monocular images is essential for the target tracking task of unmanned underwater vehicles.This work proposes a method based on the Lpg-Lap Unet architecture.First,the Unet architecture integrates Laplacian pyramid depth residuals and Sobel operators to improve the boundary details in depth images,which may suffer from the feature loss caused by upsampling and the blurriness of underwater images.Multiscale local planar guidance layers then fully exploit the intermediate depth features,and a comprehensive loss function ensures robustness and accuracy.Experimental results on benchmarks demonstrate the effectiveness of Lpg-Lap Unet and its superior performance over state-of-the-art models.An underwater target tracking system is then designed to further validate its real-time capabilities in the AirSim simulation platform. 展开更多
关键词 underwater monocular depth estimation Laplacian pyramid multiscale local planar guidance underwater target tracking
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Photovoltaic Parameter Estimation Using a Parallelized Triangulation Topology Aggregation Optimization with Real-World Dataset Validation
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作者 Jun Zhe Tan Rodney H.G.Tan +4 位作者 Nor Ashidi Mat Isa Sew Sun Tiang Chun Kit Ang Kuo-Ping Lin Wei Hong Lim 《Computer Modeling in Engineering & Sciences》 2026年第2期691-736,共46页
Accurate estimation of photovoltaic(PV)parameters is essential for optimizing solar module perfor-mance and enhancing resource efficiency in renewable energy systems.This study presents a process innovation by introdu... Accurate estimation of photovoltaic(PV)parameters is essential for optimizing solar module perfor-mance and enhancing resource efficiency in renewable energy systems.This study presents a process innovation by introducing,for the first time,the Triangulation Topology Aggregation Optimizer(TTAO)integrated with parallel computing to address PV parameter estimation challenges.The effectiveness and robustness of TTAO are rigorously evaluated using two standard benchmark datasets(KC200GT and R.T.C.France solar cells)and a real-world dataset(Poly70W solar module)under single-,double-,and triple-diode configurations.Results show that TTAO consistently achieves superior accuracy by producing the lowest RMSE values and faster convergence compared to state-of-the-art metaheuristic algorithms.In addition,the integration of parallel computing significantly enhances computational efficiency,reducing execution time by up to 85%without compromising accuracy.Validation using real-world data further demonstrates TTAO’s adaptability and practical relevance in renewable energy systems,effectively bridging the gap between theoretical modeling and real-world implementation for PV system monitoring and optimization,contributing to climate mitigation through improved solar energy performance. 展开更多
关键词 Photovoltaic(PV) parameters estimation triangulation topology aggregation optimizer(TTAO) parallel computing OPTIMIZATION
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Estimation of cross-sectional areas of individual tree stems using remotely collected data
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作者 Gabriel Lessa Lavagnoli Gilson Fernandes da Silva +3 位作者 Giovanni Correia Vieira André Quintao Almeida Adriano Ribeiro de Mendonca Carlos Pedro Boechat Soares 《Journal of Forestry Research》 2026年第1期216-229,共14页
We investigated the impact of convexity and isoperimetric deficits on the accuracy of sectional area estimates of tree stems using traditional methods(caliper,tape,formulas based on stem diameter and circumference).In... We investigated the impact of convexity and isoperimetric deficits on the accuracy of sectional area estimates of tree stems using traditional methods(caliper,tape,formulas based on stem diameter and circumference).In two complementary experiments,the use of photographs to estimate cross-sectional areas was first validated,then the use of a caliper and diameter tape was computer-simulated.The results indicated that the photographic method offers high precision,with mean relative errors below 0.1%,minimal deviation,and no significant bias,and the traditional methods led to substantial and systematic errors,with deviations from circularity and convexity significantly increasing the errors in area estimation. 展开更多
关键词 Tree cross-sectional area measurement Isoperimetric decit Convexity decit Photographic estimation Forest mensuration Stem geometry Error analysis
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High-sensitivity phase estimation with a two-mode squeezed coherent state based on a Mach–Zehnder interferometer
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作者 Pengxiang Ruan Jun Liu +3 位作者 Chenlu Li Qingli Jing Mingming Zhang Dong-Xu Chen 《Chinese Physics B》 2026年第2期389-400,共12页
A scheme is proposed based on a Mach-Zehnder interferometer with high phase sensitivity,utilizing a two-mode squeezed coherent state,generated by four-wave mixing,as input.The phase sensitivity of this scheme easily s... A scheme is proposed based on a Mach-Zehnder interferometer with high phase sensitivity,utilizing a two-mode squeezed coherent state,generated by four-wave mixing,as input.The phase sensitivity of this scheme easily surpasses the Heisenberg limit when intensity difference detection is applied.Under phase-matching conditions,the quantum Cramér-Rao bound significantly exceeds the Heisenberg limit.Additionally,the scheme exhibits robustness against photon loss.When compared with the modified SU(1,1)interferometer with two coherent state inputs,this approach demonstrates superior measurement sensitivity,evaluated through various detection methods and the quantum Cramér-Rao bound.This work holds potential applications in quantum metrology. 展开更多
关键词 two-mode squeezed coherent state phase estimation quantum Cramér–Rao bound Heisenberg limit
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Time Delay Estimation of Target Echo Signal Based on Multi-bright Spot Echoes
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作者 Ge Yu Fan Du +1 位作者 Xiukun Li Yan Li 《哈尔滨工程大学学报(英文版)》 2026年第1期312-325,共14页
Accurate time delay estimation of target echo signals is a critical component of underwater target localization.In active sonar systems,echo signal processing is vulnerable to the effects of reverberation and noise in... Accurate time delay estimation of target echo signals is a critical component of underwater target localization.In active sonar systems,echo signal processing is vulnerable to the effects of reverberation and noise in the maritime environment.This paper proposes a novel method for estimating target time delay using multi-bright spot echoes,assuming the target’s size and depth are known.Aiming to effectively enhance the extraction of geometric features from the target echoes and mitigate the impact of reverberation and noise,the proposed approach employs the fractional order Fourier transform-frequency sliced wavelet transform to extract multi-bright spot echoes.Using the highlighting model theory and the target size information,an observation matrix is constructed to represent multi-angle incident signals and obtain the theoretical scattered echo signals from different angles.Aiming to accurately estimate the target’s time delay,waveform similarity coefficients and mean square error values between the theoretical return signals and received signals are computed across various incident angles and time delays.Simulation results show that,compared to the conventional matched filter,the proposed algorithm reduces the relative error by 65.9%-91.5%at a signal-to noise ratio of-25 dB,and by 66.7%-88.9%at a signal-to-reverberation ratio of−10 dB.This algorithm provides a new approach for the precise localization of submerged targets in shallow water environments. 展开更多
关键词 Multi-bright spot echoes Time-delay estimation Target echo signal Frequency sliced wavelet transform Fractional order fourier transform
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Ugonin J Inhibits EMT and Migration in Prostate Cancer by Suppressing ADAM9 Expression
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作者 Jo-Yu Lin Tien-Huang Lin +5 位作者 Ya-Jing Jiang Liang-Wei Lin Kuan-Ying Lai Yi-Chin Fong Chih-Chuang Liaw Chih-Hsin Tang 《Oncology Research》 2026年第3期523-538,共16页
Background:Prostate cancer(PCa)is the most prevalent malignancy in men and often correlates with distant metastasis in its advanced stages.The study aimed to investigate the effects of Ugonin J,a natural compound isol... Background:Prostate cancer(PCa)is the most prevalent malignancy in men and often correlates with distant metastasis in its advanced stages.The study aimed to investigate the effects of Ugonin J,a natural compound isolated from Helminthostachys zeylanica,on PCa metastasis.Methods:The effects of Ugonin J on cell motility were assessed using migration and invasion assays.Reverse Transcription Quantitative PCR(RT-qPCR)and Western blotting were used to evaluate the impact of Ugonin J on mRNA and protein expression.RNA sequencing(RNA-seq)analysis was performed to investigate candidate mechanisms.Differential gene expression analysis in PCa patients was conducted using multiple databases.Results:Here,we reveal that Ugonin J blocks migration and invasion in PCa cells without affecting cell viability.RNA-seq analysis suggests that epithelial-mesenchymal transition(EMT)is potentially involved in Ugonin J’s anti-motility effects.Ugonin J also suppresses the expression of mesenchymal markers N-cadherin,β-catenin,Snail,and Slug while upregulating the expression of the epithelial marker E-cadherin.Furthermore,among 13 A disintegrin and metalloproteinase(ADAM)proteins,A disintegrin and metalloproteinase domain-containing protein 9(ADAM9)is the most downregulated following Ugonin J treatment,according to our RNA-seq data.Importantly,clinical data revealed that ADAM9 expression are higher in PCa patients than in healthy controls and are associated with distant metastasis.Transfection with ADAM9 cDNA reverses Ugonin J-regulated downregulation of EMT,migration,and invasion in PCa cells.Ugonin J inhibits ADAM9-dependent motility by downregulating the phosphoinositide 3-kinase(PI3K),protein kinase B(Akt)and nuclear factor-κB(NF-κB)pathways.Conclusions:Our evidence suggests that Ugonin J is a novel therapeutic candidate for further development as a treatment for metastatic PCa. 展开更多
关键词 Prostate cancer Ugonin J epithelial-mesenchymal transition(EMT) a disintegrin and metalloproteinase domain-containing protein 9(adam9)
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Advanced Meta-Heuristic Optimization for Accurate Photovoltaic Model Parameterization:A High-Accuracy Estimation Using Spider Wasp Optimization
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作者 Sarah M.Alhammad Diaa Salama AbdElminaam +1 位作者 Asmaa Rizk Ibrahim Ahmed Taha 《Computers, Materials & Continua》 2026年第3期2269-2303,共35页
Accurate parameter extraction of photovoltaic(PV)models plays a critical role in enabling precise performance prediction,optimal system sizing,and effective operational control under diverse environmental conditions.W... Accurate parameter extraction of photovoltaic(PV)models plays a critical role in enabling precise performance prediction,optimal system sizing,and effective operational control under diverse environmental conditions.While a wide range of metaheuristic optimisation techniques have been applied to this problem,many existing methods are hindered by slow convergence rates,susceptibility to premature stagnation,and reduced accuracy when applied to complex multi-diode PV configurations.These limitations can lead to suboptimal modelling,reducing the efficiency of PV system design and operation.In this work,we propose an enhanced hybrid optimisation approach,the modified Spider Wasp Optimization(mSWO)with Opposition-Based Learning algorithm,which integrates the exploration and exploitation capabilities of the Spider Wasp Optimization(SWO)metaheuristic with the diversityenhancing mechanism of Opposition-Based Learning(OBL).The hybridisation is designed to dynamically expand the search space coverage,avoid premature convergence,and improve both convergence speed and precision in highdimensional optimisation tasks.The mSWO algorithm is applied to three well-established PV configurations:the single diode model(SDM),the double diode model(DDM),and the triple diode model(TDM).Real experimental current-voltage(I-V)datasets from a commercial PV module under standard test conditions(STC)are used for evaluation.Comparative analysis is conducted against eighteen advanced metaheuristic algorithms,including BSDE,RLGBO,GWOCS,MFO,EO,TSA,and SCA.Performance metrics include minimum,mean,and maximum root mean square error(RMSE),standard deviation(SD),and convergence behaviour over 30 independent runs.The results reveal that mSWO consistently delivers superior accuracy and robustness across all PV models,achieving the lowest RMSE values of 0.000986022(SDM),0.000982884(DDM),and 0.000982529(TDM),with minimal SD values,indicating remarkable repeatability.Convergence analyses further show that mSWO reaches optimal solutions more rapidly and with fewer oscillations than all competing methods,with the performance gap widening as model complexity increases.These findings demonstrate that mSWO provides a scalable,computationally efficient,and highly reliable framework for PV parameter extraction.Its adaptability to models of growing complexity suggests strong potential for broader applications in renewable energy systems,including performance monitoring,fault detection,and intelligent control,thereby contributing to the optimisation of next-generation solar energy solutions. 展开更多
关键词 modified Spider Wasp Optimizer(mSWO) photovoltaic(PV)modeling meta-heuristic optimization solar energy parameter estimation renewable energy technologies
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基于ADAMS的固定式仿形控深割胶机研制 被引量:1
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作者 张喜瑞 孙鹤鸣 +3 位作者 刘俊孝 张志富 郭杰 张丽娜 《农业工程学报》 北大核心 2025年第22期62-71,共10页
针对天然橡胶割胶作业中树皮表面凹凸不平导致进刀深度不稳定的问题,该研究设计了一种集成仿形控深装置的固定式割胶机。通过对关键结构的设计和理论分析,确定了影响割胶进刀深度稳定性的重要因素。利用三维激光扫描技术构建橡胶树高精... 针对天然橡胶割胶作业中树皮表面凹凸不平导致进刀深度不稳定的问题,该研究设计了一种集成仿形控深装置的固定式割胶机。通过对关键结构的设计和理论分析,确定了影响割胶进刀深度稳定性的重要因素。利用三维激光扫描技术构建橡胶树高精度模型,结合ADAMS仿真软件进行动力学仿真与三水平正交试验,以仿形部件的曲率半径、拉簧刚度系数和扭簧刚度系数作为试验因素,以进刀深度合格率作为评价指标,通过响应面优化得到了最佳参数组合:仿形部件曲率半径12.35 mm、拉簧刚度系数87.19 N/m、扭簧刚度系数10.04 N·m/rad时,进刀深度合格率达95.33%。通过上述优化,该装置能自适应不同凹凸的树皮表面,确保割胶时进刀深度稳定,从而减少树皮损伤。林间试验表明,该装置可精准跟踪树皮表面凹凸变化,平均进刀深度合格率91.77%,相对于不具备仿形部件的割胶机进刀深度合格率提高了12.51个百分点,橡胶树皮损伤降低。研究结果为复杂表面自适应控制提供了解决方案,可为固定式仿形控深割胶机设计提供参考。 展开更多
关键词 仿形 adamS 割胶机 进刀深度 三维激光扫描
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