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The Existence of Meromorphic Solutions to Non-Linear Delay Differential Equations
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作者 Mingyue Wu 《Open Journal of Applied Sciences》 2023年第12期2329-2342,共14页
In this paper, we study the existence of the transcendental meromorphic solution of the delay differential equations , where a(z) is a rational function, and are polynomials in w(z) with rational c... In this paper, we study the existence of the transcendental meromorphic solution of the delay differential equations , where a(z) is a rational function, and are polynomials in w(z) with rational coefficients, k is a positive integer. Under the assumption when above equations own transcendental meromorphic solutions with minimal hyper-type, we derive the concrete conditions on the degree of the right side of them. Specially, when w(z)=0 is a root of , its multiplicity is at most k. Some examples are given here to illustrate that our results are accurate. 展开更多
关键词 non-linear Delay differential Equations Painlevé Type Equations Nevanlinna Theory Meromorphic Function Solutions Minimal Hypertype
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Determination of Trace Nickel in Manganese Dioxide by Differential Pulse Polarography
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作者 杨生恕 俞征 《Rare Metals》 SCIE EI CAS CSCD 1995年第3期230-233,共4页
DeterminationofTraceNickelinManganeseDioxidebyDifferentialPulsePolarographyYangShengshuandYuZheng(杨生恕)(俞征)(D... DeterminationofTraceNickelinManganeseDioxidebyDifferentialPulsePolarographyYangShengshuandYuZheng(杨生恕)(俞征)(DeptofChemistry,Gu... 展开更多
关键词 trace NICKEL MANGANESE dioxide differential PULSE polarogra-phy
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Oscillation Criteria of second Order Non-Linear Differential Equations
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作者 Hishyar Kh. Abdullah 《Open Journal of Applied Sciences》 2012年第4期120-122,共3页
In this paper we are concerned with the oscillation criteria of second order non-linear homogeneous differential equation. Example have been given to illustrate the results.
关键词 component OSCILLATORY SECOND order differential EQUATIONS non-linear.
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Double Elzaki Transform Decomposition Method for Solving Non-Linear Partial Differential Equations
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作者 Moh A. Hassan Tarig M. Elzaki 《Journal of Applied Mathematics and Physics》 2020年第8期1463-1471,共9页
In this paper, we discuss a new method employed to tackle non-linear partial differential equations, namely Double Elzaki Transform Decomposition Method (DETDM). This method is a combination of the Double ELzaki Trans... In this paper, we discuss a new method employed to tackle non-linear partial differential equations, namely Double Elzaki Transform Decomposition Method (DETDM). This method is a combination of the Double ELzaki Transform and Adomian Decomposition Method. This technique is hereafter provided and supported with necessary illustrations, together with some attached examples. The results reveal that the new method is very efficient, simple and can be applied to other non-linear problems. 展开更多
关键词 Double Elzaki Transform Adomian Decomposition Method non-linear Partial differential Equations
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ON THE BOUNDEDNESS AND PERIODICITY OF THESOLUTIONS OF A CERTAIN VECTOR DIFFERENTIALEQUATION OF THIRD-ORDER
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作者 Cemil Tune(University of Yuzuncu Yil, Faculty of Education, 65080, VAN, TURKEY) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第2期163-170,共8页
There are given sufficient conditions for the ultimate boundedness of solutions and for the existence of periodic solutions of a certain vector differential equation of third-order.
关键词 system of non-linear differential equations of the THIRD-ORDER ULTIMATE BOUNDEDNESS periodic solutions
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Determination of Consuming Rate for Pb-Ag-Ca Anode in Preparation of Electrolytic MnO_2 by Differential Pulse Polarography
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作者 俞征 杨生恕 《Rare Metals》 SCIE EI CAS CSCD 1995年第2期144-149,共6页
DeterminationofConsumingRateforPb-Ag-CaAnodeinPreparationofElectrolyticMnO_2byDifferentialPulsePolarographyY... DeterminationofConsumingRateforPb-Ag-CaAnodeinPreparationofElectrolyticMnO_2byDifferentialPulsePolarographyYuZhengandYangShen... 展开更多
关键词 Electrolyte MnSO4H2SO4 trace lead differential PULSE POLAROGRAPHY Pb-Ag-Ca ANODE Consuming RATE
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Measurements of NO_2 mixing ratios with topographic target light scattering-differential optical absorption spectroscopy system and comparisons to point monitoring technique
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作者 王杨 李昂 +6 位作者 谢品华 曾议 王瑞斌 陈浩 裴显 刘建国 刘文清 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期285-290,共6页
A topographic target light scattering-differential optical absorption spectroscopy(ToTaL-DOAS) system is developed for measuring average concentrations along a known optical path and studying surface-near distribution... A topographic target light scattering-differential optical absorption spectroscopy(ToTaL-DOAS) system is developed for measuring average concentrations along a known optical path and studying surface-near distributions of atmospheric trace gases.The telescope of the ToTaL-DOAS system points to targets which are located at known distances from the measurement device and illuminated by sunlight.Average concentrations with high spatial resolution can be retrieved by receiving sunlight reflected from the targets.A filed measurement of NO2 concentration is performed with the ToTaL-DOAS system in Shijiazhuang in the autumn of 2011.The measurement data are compared with concentrations measured by the point monitoring technique at the same site.The results show that the ToTaL-DOAS system is sensitive to the variation of NO2 concentrations along the optical path. 展开更多
关键词 差分光学吸收光谱法 DOAS系统 监测技术 测量点 NO2 光散射 地形 混合比
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鲁西郗山—关帝庙地区碱性杂岩体微量元素地球化学特征及其意义
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作者 王巧云 郝兴中 +4 位作者 兰君 王立功 陈磊 郭晶 胡创业 《山东国土资源》 2024年第3期23-32,共10页
本文在详细的岩相学观察基础上,分析研究岩体和矿物的微量元素及稀土元素的特征。结果表明,郗山—关帝庙碱性杂岩体富集Ba、U、Pb、Th及La、Ce,亏损Nb、Ta、Zr、Hf;Nb>Ta,富集轻稀土元素、亏损重稀土元素,轻重稀土分异显著,Ce、Eu无... 本文在详细的岩相学观察基础上,分析研究岩体和矿物的微量元素及稀土元素的特征。结果表明,郗山—关帝庙碱性杂岩体富集Ba、U、Pb、Th及La、Ce,亏损Nb、Ta、Zr、Hf;Nb>Ta,富集轻稀土元素、亏损重稀土元素,轻重稀土分异显著,Ce、Eu无明显异常,关帝庙岩体与郗山岩体的微量元素配分曲线均为右倾型,表明研究区内碱性岩体为同源岩浆,推测初始成岩物质来源于岩石圈地幔部分熔融,其母岩浆为碳酸盐化硅酸岩熔体。郗山岩体发现岩浆型磷灰石和热液型磷灰石,表明郗山岩体的岩浆经历了较强的结晶分异和一定程度的混合作用,并在热液阶段形成大量的轻稀土矿物。 展开更多
关键词 微量元素 岩浆结晶分异 岩浆—流体作用 郗山—关帝庙 鲁西
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基于多元素分析的贵州绿茶产地鉴别研究
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作者 罗玉航 况晓宇 +3 位作者 周绍均 袁付明 刘桂岚 阁世媚 《食品安全质量检测学报》 CAS 2024年第1期20-28,共9页
目的探究以多元素统计对贵州不同产地绿茶判别分析的有效性和可行性,筛选产地间差异性元素。方法采用电感耦合等离子体发射光谱法(inductively coupled plasma emission spectrometry,ICP-OES)和电感耦合等离子体质谱法(inductively cou... 目的探究以多元素统计对贵州不同产地绿茶判别分析的有效性和可行性,筛选产地间差异性元素。方法采用电感耦合等离子体发射光谱法(inductively coupled plasma emission spectrometry,ICP-OES)和电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry,ICP-MS)对贵州4个产地63个绿茶样品中47种元素进行定量分析,结合正交偏最小二乘法判别分析(orthogonal partial least squares discriminant analysis,OPLS-DA)建立贵州绿茶的产地判别模型。结果4个产地的绿茶中元素含量有明显的差异;K、P、Ca、Mg、Mn、Al和Fe元素含量规律相同,说明4个产地的茶叶对土壤中部分高含量元素的富集能力具有一致性;4个产地的污染物Pb、Cu、Cd、As和Cr的含量均低于茶叶相关标准的限量要求。基于元素含量建立的6组OPLS-DA分析模型可以有效区分产地,其中黔西南州与铜仁市模型(QXN-TR)参数最优,该模型用50.3%的变量可解释93.8%的组间差异,模型预测能力也能达到89.7%;6组模型中共筛选出20种差异性元素,在6组产地判别模型中未找到共有元素;稀土元素在4个产地的判别上贡献有限。结论综合结果表明,以多元素分析和统计学模型针对贵州不同产地的绿茶样本进行判别分析是可行的,整体区分效果良好;不同产地的绿茶间元素含量的差异不同;为贵州绿茶产地区分提供了思路和研究基础。 展开更多
关键词 绿茶 微量元素 产地判别 差异性元素 正交偏最小二乘法判别分析
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采用差分星座图的SDR设备射频指纹识别
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作者 安永丽 申俊峰 纪占林 《电讯技术》 北大核心 2024年第3期442-450,共9页
差分星座图(Differential Constellation Trace Figure,DCTF)在射频指纹(Radio Frequency Fingerprint,RFF)识别中具有良好的性能,但在低信噪比情况下会产生严重的模糊。为了提高DCTF的识别精度,设计了注意力残差卷积神经网络模型,即DCT... 差分星座图(Differential Constellation Trace Figure,DCTF)在射频指纹(Radio Frequency Fingerprint,RFF)识别中具有良好的性能,但在低信噪比情况下会产生严重的模糊。为了提高DCTF的识别精度,设计了注意力残差卷积神经网络模型,即DCTF-Res2Net模型。该模型在网络提取特征时加入注意力模块来提高DCTF的识别精度,并将标签平滑损失函数与网络模型结合,有效缓解了DCTF中的离群点对网络模型的干扰。在实验中,根据不同的传输方式和传输场景构建了完备的DCTF的数据集,并用DCTF-Res2Net模型对其进行分类。实验结果表明,在信噪比为5 dB的情况下,与传统的残差网络相比,所提出的DCTF-Res2Net模型可以达到更高的识别精度。 展开更多
关键词 射频指纹识别 物理层安全 差分星座图(DCTF) 注意力残差网络
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ON THE HOLOMORPHIC SOLUTION OF NON-LINEAR TOTALLY CHARACTERISTIC EQUATIONS WITH SEVERAL SPACE VARIABLES 被引量:5
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作者 陈化 罗壮初 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期393-403,共11页
In this paper the authors study a class of non-linear singular partial differential equation in complex domain Ct x Cxn. Under certain assumptions, they prove the existence and uniqueness of holomorphic solution near ... In this paper the authors study a class of non-linear singular partial differential equation in complex domain Ct x Cxn. Under certain assumptions, they prove the existence and uniqueness of holomorphic solution near origin of Ct x Cxn. 展开更多
关键词 non-linear SINGULAR partial differential equation HOLOMORPHIC SOLUTION
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Non-Linear Mathematical Model of the Interaction between Tumor and Oncolytic Viruses 被引量:1
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作者 Seetharaman Usha Vairamani Abinaya +1 位作者 Shunmugham Loghambal Lakshmanan Rajendran 《Applied Mathematics》 2012年第9期1089-1096,共8页
A mathematical modeling of tumor therapy with oncolytic viruses is discussed. The model consists of two coupled, deterministic differential equations allowing for cell reproduction and death, and cell infection. The m... A mathematical modeling of tumor therapy with oncolytic viruses is discussed. The model consists of two coupled, deterministic differential equations allowing for cell reproduction and death, and cell infection. The model is one of the conceptual mathematical models of tumor growth that treat a tumor as a dynamic society of interacting cells. In this paper, we obtain an approximate analytical expression of uninfected and infected cell population by solving the non-linear equations using Homotopy analysis method (HAM). Furthermore, the results are compared with the numerical simulation of the problem using Matlab program. The obtained results are valid for the whole solution domain. 展开更多
关键词 MATHEMATICAL Modeling non-linear differential Equations Numerical Simulation HOMOTOPY Analysis Method TUMOR Cells ONCOLYTIC Viruses
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Distribution of selenium and arsenic in differentiated multicellular eukaryotic fossils and their significance
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作者 Jie Long Shixi Zhang Kunli Luo 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第3期821-833,共13页
We present variation patterns of trace elements within different sequences of the Ediacaran Doushantuo Formation(DST,635-551 million years ago),and inside the cells of the earliest differentiated multicellular eukaryo... We present variation patterns of trace elements within different sequences of the Ediacaran Doushantuo Formation(DST,635-551 million years ago),and inside the cells of the earliest differentiated multicellular eukaryotic fossils of the Weng'an biota in the Weng'an County of Guizhou Province.The results showed that selenium is the most enriched and significantly varied trace element among the 22 trace elements throughout the DST,followed by arsenic.The highest selenium and arsenic content sequences are consistent with the first appeared sequence of the earliest differentiated multicellular eukaryotic fossils Megasphaera at the middle to upper parts of the DST.Nanoman secondary ion mass spectrometry analyses show that selenium and arsenic have an inhomogeneous and punctate distribution in the nucleus and cytoplasm.The nucleus has anomalously enriched levels of selenium and arsenic among the organelles.The selenium and arsenic concentrations exhibit a positive correlation with the diversity of fossilized Megasphaera.These new findings give us a clue that the anomalous enrichment of selenium and arsenic might contributes to the cell differentiation in Ediacaran Doushantuo period. 展开更多
关键词 trace elements enrichment Weng'an BIOTA EDIACARAN Megasphaera Cell differentiation
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Analysis of non-linear reaction-diffusion processes with Michaelis-Menten kinetics by a new Homotopy perturbation method
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作者 Devaraj Shanthi Vembu Ananthaswamy Lakshmanan Rajendran 《Natural Science》 2013年第9期1034-1046,共13页
This paper demonstrates the approximate analytical solution to a non-linear singular two-point boundary-value problem which describes oxygen diffusion in a planar cell. The model is based on diffusion equation contain... This paper demonstrates the approximate analytical solution to a non-linear singular two-point boundary-value problem which describes oxygen diffusion in a planar cell. The model is based on diffusion equation containing a non-linear term related to Michaelis-Menten kinetics of enzymatic reaction. Approximate analytical expression of concentration of oxygen is derived using new Homotopy perturbation method for various boundary conditions. The validity of the obtained solutions is verified by the numerical results. 展开更多
关键词 Oxygen Diffusion MICHAELIS-MENTEN non-linear differential EQUATIONS NEW HOMOTOPY PERTURBATION Method Numerical Simulation
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Trace Representations of S-boxes and Their Application
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作者 ZengXiang-yong FuJian-ming +1 位作者 LiuHe-guo ZhangHuan-guo 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第2期173-176,共4页
In the paper, we use trace representations of Boolean functions to obtain that a class mappings including functions F(x)=x d over field GF(2 n), with W(d)=n-1, have desirable cryptographic properties. Therefore we gen... In the paper, we use trace representations of Boolean functions to obtain that a class mappings including functions F(x)=x d over field GF(2 n), with W(d)=n-1, have desirable cryptographic properties. Therefore we generalize an important result of Nyberg. As application, we use these conclusions to analyze cryptographic property of the S-box of AES (the Advanced Encryption Standard) and give its several equivalent representations, proving that the composition of inversion function of AES and any invertible affine transformations is impossible to satisfy strict avalanche criterion,any order propagation criteria and any order correlation immunity. 展开更多
关键词 替换盒 Boolean函数 数据加密 迹函数 对称密码系统
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一种永磁同步电机效率优化控制策略研究 被引量:3
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作者 王红 于新红 《电子设计工程》 2023年第16期16-20,共5页
为提升永磁同步电机的效率指标,提出一种基于跟踪微分器的效率优化控制策略,该策略通过建立损耗模型,分析损耗功率与定子磁链的极值关系,在直接转矩控制下重构损耗功率函数,将损耗功率函数的电机参数个数降到最少,利用跟踪微分器来求解... 为提升永磁同步电机的效率指标,提出一种基于跟踪微分器的效率优化控制策略,该策略通过建立损耗模型,分析损耗功率与定子磁链的极值关系,在直接转矩控制下重构损耗功率函数,将损耗功率函数的电机参数个数降到最少,利用跟踪微分器来求解永磁同步电机不同运行工况下的最优定子磁链。该控制策略不仅能实现控制系统的全局效率最优,而且具有良好的动态特性和较强的鲁棒性。通过与传统损耗模型控制策略进行仿真实验结果对比分析,验证了所提控制策略的有效性。 展开更多
关键词 永磁同步电机 损耗模型 跟踪微分器 最优定子磁链
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基于残差原型网络的辐射源个体识别 被引量:1
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作者 王春升 王永民 +1 位作者 许华 朱华丽 《系统工程与电子技术》 EI CSCD 北大核心 2023年第7期2249-2258,共10页
利用深度学习进行通信辐射源识别分类时,现有算法在较低信噪比下的识别能力还不足,且均着重关注各类辐射源个体的类间距离,忽视了类内紧密性。针对此问题,结合残差网络和原型学习基本思想,提出残差原型网络,对输入信号的差分星座轨迹图... 利用深度学习进行通信辐射源识别分类时,现有算法在较低信噪比下的识别能力还不足,且均着重关注各类辐射源个体的类间距离,忽视了类内紧密性。针对此问题,结合残差网络和原型学习基本思想,提出残差原型网络,对输入信号的差分星座轨迹图进行识别。此外,在基于距离的交叉熵损失函数基础上加入原型损失,通过提高类内紧密度的方式进一步扩增了类间距离。通过对5种ZigBee设备的实验,结果表明所提算法在相同信噪比条件下相较于其他算法具有更好的识别性能,在信噪比高于8 dB时,可达到99%以上的准确率。 展开更多
关键词 残差原型网络 原型学习 辐射源个体识别 差分星座轨迹图
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胆管癌患者微量金属质量分数与肿瘤进展的关系
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作者 张宏龙 严俊 李汛 《兰州大学学报(医学版)》 2023年第11期33-41,共9页
目的探讨微量金属在胆管癌患者肿瘤组织与肿瘤旁组织中的分布差异,分析微量金属质量分数与肿瘤分化程度和淋巴结转移的关系,为胆管癌的靶向治疗提供依据。方法选择兰州大学第一医院2012年1月—2015年12月通过病理学检测诊断为胆管癌的... 目的探讨微量金属在胆管癌患者肿瘤组织与肿瘤旁组织中的分布差异,分析微量金属质量分数与肿瘤分化程度和淋巴结转移的关系,为胆管癌的靶向治疗提供依据。方法选择兰州大学第一医院2012年1月—2015年12月通过病理学检测诊断为胆管癌的住院患者为研究对象,术中收集配对肿瘤组织和肿瘤旁健康组织,使用电感耦合等离子体质谱仪分析Cd、Co、Fe、Mn、Ni、Pb、Se、Zn 8种微量金属质量分数。采用Logistic回归和贝叶斯核机器回归模型探讨微量金属质量分数与胆管癌肿瘤分化程度和淋巴结转移的关系。结果肿瘤组织显示比肿瘤旁组织更低的Cd、Co、Fe、Ni质量分数(P<0.05)。发现肿瘤分化不良和淋巴结转移阳性的胆管癌患者拥有更低的Cd、Fe、Ni、Pb质量分数(P<0.05),并且肿瘤组织中Cd(OR=1.00,95%CI:[0.99,1.00])和Fe质量分数(OR=0.97,95%CI:[0.94,0.99])与胆管癌分化程度呈负相关关系(P<0.05)。贝叶斯核机器回归模型显示混合金属质量分数与胆管癌患者肿瘤分化程度和淋巴结转移呈显著负相关关系,且Cd、Ni是相关性最大的金属。结论微量金属质量分数的变化可能与胆管癌进展有关。 展开更多
关键词 胆管癌 微量金属 肿瘤组织 肿瘤旁组织 肿瘤分化不良 淋巴结转移
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基于差分星座轨迹图的多任务802.11b/g信号识别方法
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作者 谢星丽 谢跃雷 《电讯技术》 北大核心 2023年第11期1771-1778,共8页
针对802.11b/g无线信号的调制方式识别和辐射源个体识别问题,提出了一种基于差分星座轨迹图的多任务卷积神经网络识别方法。将调制识别和辐射源个体识别看作两个相互关联的学习任务,通过共享参数的深度网络提取差分星座轨迹图的特征,并... 针对802.11b/g无线信号的调制方式识别和辐射源个体识别问题,提出了一种基于差分星座轨迹图的多任务卷积神经网络识别方法。将调制识别和辐射源个体识别看作两个相互关联的学习任务,通过共享参数的深度网络提取差分星座轨迹图的特征,并由结构不同的两个分支网络进行分类识别,同时对这两个任务进行联合优化训练并相互促进学习。实验中使用6个不同的路由器进行验证,结果表明相比于单任务模型的识别方法,多任务模型所用的训练时长和模型所占内存均比两个单任务模型之和少,同时对辐射源个体、调制方式的识别率分别平均提高了1.17%和3%。 展开更多
关键词 辐射源识别 调制方式识别 差分星座轨迹图 多任务学习 深度学习
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锑原位掺杂SiO_(2)@PDA-Sb复合材料修饰电极用于海水中Zn离子检测
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作者 常粟淮 兰旺荣 +1 位作者 程薛霖 黄旭光 《应用海洋学学报》 CSCD 北大核心 2023年第1期118-127,共10页
本研究提出了一种用于检测海水中锌离子(Zn^(2+))含量的电化学检测方法。该方法首先应用水热法合成SiO_(2)@PDA-Sb复合材料,然后将该复合材料修饰到玻碳电极上制备SiO_(2)@PDA-Sb-Nafion/GCE,利用差分脉冲阳极溶出伏安法(DPASV)对珠江... 本研究提出了一种用于检测海水中锌离子(Zn^(2+))含量的电化学检测方法。该方法首先应用水热法合成SiO_(2)@PDA-Sb复合材料,然后将该复合材料修饰到玻碳电极上制备SiO_(2)@PDA-Sb-Nafion/GCE,利用差分脉冲阳极溶出伏安法(DPASV)对珠江口海水水样中Zn^(2+)进行测定。研究结果表明,Zn^(2+)在SiO_(2)@PDA-Sb-Nafion/GCE上具有较强的溶出峰。在最优条件下,SiO_(2)@PDA-Sb-Nafion/GCE对Zn^(2+)浓度在1~1000 nmol/L范围内可实现灵敏、准确的检测,Zn^(2+)的检测出限为0.71 nmol/L。加标回收率实验显示Zn^(2+)加标回收率为93.19%~100.12%,表明该方法可应用于现场海水样品Zn^(2+)测定。本方法具有电极制作简单、稳定性和抗干扰性良好,能够提高现有测定方法的检测限和精确度,在现场海水检测痕量Zn^(2+)具有较好的应用前景。 展开更多
关键词 海洋化学 锑原位掺杂 差分脉冲阳极溶出伏安法 痕量锌离子 海水
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