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Correlation Degree and Correlation Coefficient of Multi-Output Functions 被引量:1
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作者 JUGui-zhi ZHAOYa-qun 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第1期195-198,共4页
We present definitions of the correlation degree and correlation coefficient of multi-output functions. Two relationships about the correlation degree of multi-output functions are proved. One is between the correlati... We present definitions of the correlation degree and correlation coefficient of multi-output functions. Two relationships about the correlation degree of multi-output functions are proved. One is between the correlation degree and independency, the other is between the correlation degree and balance. Especially the paper discusses the correlation degree of affine multioutput functions. We demonstrate properties of the correlation coefficient of multi-output functions. One is the value range of the correlation coefficient, one is the relationship between the correlation coefficient and independency, and another is the sufficient and necessary condition that two multi-output functions are equivalent to each other. 展开更多
关键词 Key words multi output functions independency correlation degree BALANCE correlation coefficient
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Walsh Spectral Characteristics and the Auto-Correlation Function Characteristics of Forming Orthomorphic Permutations of Multi-Output Functions 被引量:4
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作者 ZHAO Yaqun WANG Jue 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1895-1898,共4页
Orthomorphic permutations have good characteristics in cryptosystems. In this paper, by using of knowledge about relation between orthomorphic permutations and multi-output functions, and conceptions of the generalize... Orthomorphic permutations have good characteristics in cryptosystems. In this paper, by using of knowledge about relation between orthomorphic permutations and multi-output functions, and conceptions of the generalized Walsh spectrum of multi-output functions and the auto-correlation function of multi-output functions to investigate the Walsh spectral characteristics and the auto-correlation function characteristics of orthormophic permutations, several results are obtained. 展开更多
关键词 orthomorphic permutation multi-output functions walsh spectral auto-correlation function
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Relationship between Multi-Output Partially Bent Functions and Multi-Output Bent Functions 被引量:2
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作者 ZHAO Yaqun JU Guizhi WANG Jue 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1887-1890,共4页
In this paper, the definition of multl-output partially Bent functions is presented and some properties are discussed. Then the relationship between multi-output partially Bent functions and multi-output Bent function... In this paper, the definition of multl-output partially Bent functions is presented and some properties are discussed. Then the relationship between multi-output partially Bent functions and multi-output Bent functions is given in Theorem 4, which includes Walsh spectrum expression and function expression. This shows that multi-output partially Bent functions and multi-output Bent functions can define each other in principle. So we obtain the general method to construct multi-output partially Bent functions from multi-output Bent functions. 展开更多
关键词 multi-output partially Bent functions multi-output Bent functions Walsh spectrum CONSTRUCTING
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Multi-group pin power reconstruction method based on colorset form functions 被引量:1
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作者 HUANG Hao 《Nuclear Science and Techniques》 SCIE CAS CSCD 2009年第1期60-64,共5页
A multi-group pin power reconstruction method that fully exploits nodal information obtained from global coarse mesh solution has been developed.It expands the intra-nodal flux distributions into nonseparable semi-ana... A multi-group pin power reconstruction method that fully exploits nodal information obtained from global coarse mesh solution has been developed.It expands the intra-nodal flux distributions into nonseparable semi-analytic basis functions,and a colorset based form function generating method is proposed,which can accurately model the spectral interaction occurring at assembly interface.To demonstrate its accuracy and applicability to realistic problems, the new method is tested against two benchmark problems,including a mixed-oxide fuel problem.The results show that the new method is comparable in accuracy to fine-mesh methods. 展开更多
关键词 群组管理 LWR 二维多群辐射 输运过程 原子核
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In-plane dynamic Green's functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic half-space 被引量:3
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作者 Ba Zhenning Kang Zeqing Liang Jianwen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2018年第2期293-309,共17页
The dynamic stiffness method combined with the Fourier transform is utilized to derive the in-plane Green’s functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic(TI)half-s... The dynamic stiffness method combined with the Fourier transform is utilized to derive the in-plane Green’s functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic(TI)half-space.The loaded layer is fixed to obtain solutions restricted in it and the corresponding reactions forces,which are then applied to the total system with the opposite sign.By adding solutions restricted in the loaded layer to solutions from the reaction forces,the global solutions in the wavenumber domain are obtained,and the dynamic Green’s functions in the space domain are recovered by the inverse Fourier transform.The presented formulations can be reduced to the isotropic case developed by Wolf(1985),and are further verified by comparisons with existing solutions in a uniform isotropic as well as a layered TI halfspace subjected to horizontally distributed loads which are special cases of the more general problem addressed.The deduced Green’s functions,in conjunction with boundary element methods,will lead to significant advances in the investigation of a variety of wave scattering,wave radiation and soil-structure interaction problems in a layered TI site.Selected numerical results are given to investigate the influence of material anisotropy,frequency of excitation,inclination angle and layered on the responses of displacement and stress,and some conclusions are drawn. 展开更多
关键词 Green's functions transversely isotropic medium multi-layered half-space stiffness method dynamic response
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Development and Experiment of Multi- functional Wood Dehumidification Dryer 被引量:2
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作者 谢拥群 张壁光 +1 位作者 常建民 霍光青 《Forestry Studies in China》 CAS 2001年第2期60-64,共5页
A multi functional wood dehumidification dryer has been developed recently. The dryer can carry out air dehumidification by using only one refrigeration system, in which heat supplying and moisture air are exhausted ... A multi functional wood dehumidification dryer has been developed recently. The dryer can carry out air dehumidification by using only one refrigeration system, in which heat supplying and moisture air are exhausted by changing the position of several air dampers. In this paper, the work principles and characteristics of the dehumidification dryer are introduced, and the testing results about the thermal engineering performance of the dehumidification dryer, as well as the experiment results of drying several species of lumbers are expounded. 展开更多
关键词 multi function dehumidification dryer heat pump refrigeration system
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IMPROVEMENT OF THE ALGORITHM PRINCIPLES FOR MINIMIZATION OF MULTI-OUTPUT FUNCTIONS
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作者 陈苏 许道荣 《Journal of Electronics(China)》 1993年第2期116-123,共8页
In this paper,the application of extraction principle for logic function minimiza-tion to multi-output case is studied.A defect in original algorithm in dealing with multi-outputextrema is made up,and on this base,thr... In this paper,the application of extraction principle for logic function minimiza-tion to multi-output case is studied.A defect in original algorithm in dealing with multi-outputextrema is made up,and on this base,three kinds of less-than terms in different conditions aredefined.In addition,three kinds of generalized definition of less-than terms are given,so as to findout more efficiently the covers with minimal number of terms and irredundant function outputs.This work makes the multi-output extraction principle closer to perfection.An algorithm basedon the work is presented. 展开更多
关键词 multi-OUTPUT function MINIMIZATION Reduction of PLA MINIMAL AND-OR expression
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Solution of Multi-Delay Dynamic Systems by Using Hybrid Functions
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作者 K. Maleknejad R. Ezzati T. Damercheli 《Applied Mathematics》 2014年第13期2016-2027,共12页
In this paper, we present a method for finding the solution of the linear multi-delay systems (MDS) by using the hybrid of the Block-Pulse functions and the Bernoulli polynomials. In this approach, the MDS is reduced ... In this paper, we present a method for finding the solution of the linear multi-delay systems (MDS) by using the hybrid of the Block-Pulse functions and the Bernoulli polynomials. In this approach, the MDS is reduced to a system of linear algebraic equations by expanding various time functions for the hybrid functions and using operational matrices. To demonstrate the validity and the applicability of the technique, some examples are presented. 展开更多
关键词 Block-Pulse functions BERNOULLI POLYNOMIALS multi-Delay SYSTEMS
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Robust ranking of multi-criteria alternatives using value functions compatible with holistic preference information
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作者 SLOWINSKI Roman GRECO Salvatore2 +1 位作者 FIGUEIRA José Rui MOUSSEAU Vincent 《重庆邮电大学学报(自然科学版)》 2008年第3期324-334,共11页
We present two recent methods,called UTAGMS and GRIP,from the viewpoint of robust ranking of multi-criteria alternatives.In these methods,the preference information provided by a single or multiple Decision Makers(DMs... We present two recent methods,called UTAGMS and GRIP,from the viewpoint of robust ranking of multi-criteria alternatives.In these methods,the preference information provided by a single or multiple Decision Makers(DMs)is composed of holistic judgements of some selected alternatives,called reference alternatives.The judgements express pairwise comparisons of some reference alternatives(in UTAGMS),and comparisons of selected pairs of reference alternatives from the viewpoint of intensity of preference(in GRIP).Ordinal regression is used to find additive value functions compatible with this preference information.The whole set of compatible value functions is then used in Linear Programming(LP)to calculate a necessary and possible weak preference relations in the set of all alternatives,and in the set of all pairs of alternatives.While the necessary relation is true for all compatible value functions,the possible relation is true for at least one compatible value function.The necessary relation is a partial preorder and the possible relation is a complete and negatively transitive relation.The necessary relations show consequences of the given preference information which are robust because "always true".We illustrate this methodology with an example. 展开更多
关键词 信息处理 选择方案 函数 计算机技术
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Spectral Characteristics of the Best Affine Approach of Multi-Output m-Valued Logical Functions
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作者 ZHAO Yaqun YING Dinghai FENG Dengguo 《Wuhan University Journal of Natural Sciences》 CAS 2007年第1期185-188,共4页
This paper discusses the best affine approach (BAA) of multi-output m-valued logical functions. First, it gives the spectra of rate of accordance between multi-output m-valued logical functions and their affine func... This paper discusses the best affine approach (BAA) of multi-output m-valued logical functions. First, it gives the spectra of rate of accordance between multi-output m-valued logical functions and their affine functions, then analyzes the BAA of multi-output m-valued logical functions and finally gives the spectral characteristics of BAA of multi-output m-valued logical functions. 展开更多
关键词 multi-output m-valued logical functions linear spectrum cyclic spectrum BAA(best affine approach)
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MULTI-DIMENSIONAL GEOMETRIC BROWNIANMOTIONS, ONSAGER-MACHLUP FUNCTIONS, AND APPLICATIONS TO MATHEMATICAL FINANCE
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作者 胡耀忠 《Acta Mathematica Scientia》 SCIE CSCD 2000年第3期341-358,共18页
The solutions of the following bilinear stochastic differential equation are studied [GRAPHICS] where A(t)(k), B-t are (deterministic) continuous matrix-valued functions of t and w(1) (t),..., w(m) (t) are m independe... The solutions of the following bilinear stochastic differential equation are studied [GRAPHICS] where A(t)(k), B-t are (deterministic) continuous matrix-valued functions of t and w(1) (t),..., w(m) (t) are m independent standard Brownian motions. Conditions are given such that the solution is positive if the initial condition is positive. The equation the most probable path must satisfy is also derived and applied to a mathematical finance problem. 展开更多
关键词 multi-dimensional geometric Brownian motions Onsager-Machlup functions most probable path POSITIVITY most likely interest rate
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Optimality for Multi-Objective Programming Involving Arcwise Connected d-Type-I Functions
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作者 Guolin Yu Min Wang 《American Journal of Operations Research》 2011年第4期243-248,共6页
This paper deals with the optimality conditions and dual theory of multi-objective programming problems involving generalized convexity. New classes of generalized type-I functions are introduced for arcwise connected... This paper deals with the optimality conditions and dual theory of multi-objective programming problems involving generalized convexity. New classes of generalized type-I functions are introduced for arcwise connected functions, and examples are given to show the existence of these functions. By utilizing the new concepts, several sufficient optimality conditions and Mond-Weir type duality results are proposed for non-differentiable multi-objective programming problem. 展开更多
关键词 multi-Objective Programming Pareto Efficient Solution Arcwise Connected d-Type-I functions OPTIMALITY Conditions Duality
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Multi-objective optimization about functions of the East Lake in Wuhan
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作者 LI Xin-min LI Rong 《汉口学院学报》 2009年第3期49-52,共4页
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基于“生态-气候适应性-游憩”多功能耦合的复合绿地生态网络格局优化
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作者 周媛 黎贝 +5 位作者 李朋瑶 姚婧 陈明坤 唐密 张莉 陈娟 《生态学报》 CAS CSCD 北大核心 2024年第13期5854-5866,共13页
城市生态环境问题日益突出,如何构建多功能耦合的绿地生态网络格局是促进人居环境可持续发展的重要议题。以成都市为研究区,基于“源-汇”理论,综合运用形态学空间格局分析(Morphological Spatial Pattern Analysis,MSPA)、景观连通性... 城市生态环境问题日益突出,如何构建多功能耦合的绿地生态网络格局是促进人居环境可持续发展的重要议题。以成都市为研究区,基于“源-汇”理论,综合运用形态学空间格局分析(Morphological Spatial Pattern Analysis,MSPA)、景观连通性指数、电路理论等方法对生物多样性保护、热环境改善、游憩服务构建单因子网络,分析源地、廊道、生态战略点等空间要素特征,形成基于“生态-气候适应性-游憩”多层级、多功能复合生态网络优化格局。结果表明:(1)筛选出“源”-“汇”景观(生态159—29个,气候适应性30—14个,游憩208—40个)。生物迁徙廊道在研究区中部、西南部呈团簇状分布;气候适应性廊道呈中部集聚、东西稀疏的分布特征;游憩廊道相对密集,以中心城区为核心向四周扩散。(2)多层级“源-汇”景观网络中,总长度上,游憩廊道>生物迁徙廊道>气候适应性廊道;总面积上,生物迁徙廊道>游憩廊道>气候适应性廊道。一、二级廊道的适宜宽度为生态廊道200、100m,气候适应性廊道100、60m;游憩廊道60、30m。(3)叠加多目标廊道获得生态关键点753个,干扰点2371个。游憩源地中8.18%的面积应退让给生态廊道和气候适应性廊道。多功能耦合的生态网络优化格局可激活不同景观资源的潜在价值,对协调生态保护与城市发展的双向需求,实现绿地资源在城市空间中的最优配置具有重要意义。 展开更多
关键词 生物多样性保护 热环境改善 游憩服务 绿地生态网络 多功能耦合
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基于NSGA-Ⅱ与RBF神经网络的DPF结构参数优化
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作者 贾德文 郭岩琦 +2 位作者 雷基林 毕玉华 聂学选 《中国工程机械学报》 北大核心 2024年第1期1-6,共6页
为降低某型号柴油机颗粒捕集器(DPF)在运行过程中的流动阻力,并使其保持较高的捕集效率。采用试验设计方法抽取代表性样本集,并分析影响因素对DPF捕集性能影响的显著性。利用径向基函数(RBF)神经网络构建所选变量与目标函数映射关系代... 为降低某型号柴油机颗粒捕集器(DPF)在运行过程中的流动阻力,并使其保持较高的捕集效率。采用试验设计方法抽取代表性样本集,并分析影响因素对DPF捕集性能影响的显著性。利用径向基函数(RBF)神经网络构建所选变量与目标函数映射关系代理模型,并结合第二代非劣排序遗传算法(NSGA-Ⅱ)与结合熵权的优劣解距离排序法(TOPSIS)得到关于目标函数的一组最优解。结果表明:该型号DPF平均压降降低了14.58%,且DPF平均捕集效率保持99%以上。 展开更多
关键词 柴油机颗粒捕集器 多目标优化 捕集性能 RBF神经网络 NSGA-Ⅱ遗传算法
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矿渣-粉煤灰地聚物注浆材料配比优化方法研究
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作者 张永杰 李嘉兵 +3 位作者 邓沛宇 龙康 甘泽同 田湘 《硅酸盐通报》 CAS 北大核心 2024年第10期3726-3735,共10页
地聚物作为绿色环保、价格低廉的注浆材料,要达到良好可注性需兼顾强度和流动性等注浆性能指标。为此,以液固比、水玻璃掺量和水玻璃模数为试验因素开展室内配比优化试验,构建了抗压强度、流动度和终凝时间的多元二阶响应面回归模型,并... 地聚物作为绿色环保、价格低廉的注浆材料,要达到良好可注性需兼顾强度和流动性等注浆性能指标。为此,以液固比、水玻璃掺量和水玻璃模数为试验因素开展室内配比优化试验,构建了抗压强度、流动度和终凝时间的多元二阶响应面回归模型,并通过方差分析获得单因素及其交互作用对各注浆性能指标的影响规律。试验因素对注浆性能指标的影响程度依次为液固比、水玻璃掺量、水玻璃模数,液固比和水玻璃掺量交互作用对抗压强度的影响显著,其余两因素交互作用对注浆性能指标的影响均不显著。采用层次分析法并结合专家赋值法获取各注浆性能指标相对权重,构建多目标满意度函数对矿渣-粉煤灰地聚物注浆材料配比进行优化,据此对注浆性能指标综合最佳配比的浆液结石体进行SEM测试。结果表明,体系中仍能观测到少量球形未反应粉煤灰颗粒,矿渣颗粒和水泥颗粒基本反应完全,低聚态凝胶类反应产物重新排列和沉积延伸,相互交叉搭接构成致密且完整的空间网络状结构。 展开更多
关键词 地聚物注浆材料 多目标优化 响应面法 满意度函数 微观结构
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基于GA-SA组合算法的山区复杂环境无人机起降点选址
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作者 李章萍 贺亚蒙 《科学技术与工程》 北大核心 2024年第2期850-857,共8页
针对山区复杂环境下的物流链前端无人机货运起降点选址和任务分配进行研究。首先以建设成本最小和运输时间满意度最大为目标,综合考虑无人机自身性能和禁飞空域等因素,构建多约束条件下多目标函数的起降点选址和任务分配模型。采用遗传... 针对山区复杂环境下的物流链前端无人机货运起降点选址和任务分配进行研究。首先以建设成本最小和运输时间满意度最大为目标,综合考虑无人机自身性能和禁飞空域等因素,构建多约束条件下多目标函数的起降点选址和任务分配模型。采用遗传算法(genetic algorithm, GA)和模拟退火算法(simulated annealing algorithm, SA)的组合算法进行求解,首先通过遗传算法得出较优的可行解,再以此解作为退火算法的初始解进行模型求解。仿真结果表明,构建的多约束模型能够实现预期效果,并且采用的算法解决此类问题时具有良好的适用性。 展开更多
关键词 无人机货运 多约束条件 多目标函数 起降点选址 组合算法
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基于改进YOLOv7-tiny的大尺寸导光板缺陷检测
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作者 刘霞 王洪玎 +3 位作者 肖铭 龚烨飞 刘继承 李小伟 《化工自动化及仪表》 CAS 2024年第6期1001-1009,1034,共10页
针对导光板缺陷种类多、尺寸小、人工检测效率低的问题,提出一种基于改进YOLOv7-tiny的大尺寸导光板缺陷检测方法。首先,通过对导光板图像进行滑窗剪切以解决图像分辨率过大的问题;然后,对小样本缺陷使用多角度数据增强技术丰富数据量... 针对导光板缺陷种类多、尺寸小、人工检测效率低的问题,提出一种基于改进YOLOv7-tiny的大尺寸导光板缺陷检测方法。首先,通过对导光板图像进行滑窗剪切以解决图像分辨率过大的问题;然后,对小样本缺陷使用多角度数据增强技术丰富数据量以解决样本不均衡的问题;最后,将轻量级卷积注意力模块(CBAM)整合到YOLOv7-tiny主干特征提取部分,使模型在通道和空间上对小目标缺陷的特征提取能力得到增强;选取WIoUv2损失函数计算定位损失,增强网络对困难示例的关注度,提高算法对低质量锚框的检测能力。实验结果表明,所提方法的均值平均精度为85.8%、召回率为81.3%,与原始YOLOv7-tiny相比,分别提高了5.4%和8.1%。 展开更多
关键词 小目标缺陷检测 YOLOv7-tiny 多角度数据增强 特征提取 注意力机制 损失函数
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基于NSGA-Ⅱ传感位置优化的曲面重构及误差补偿方法
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作者 尚秋峰 张晓旭 《光子学报》 EI CAS CSCD 北大核心 2024年第2期26-36,共11页
通过优化光纤布拉格光栅形状传感技术中传感点位置和补偿重构结果来提高薄层合金板三维形状重构精度。通过ANSYS workbench建立合金板仿真模型,提取应变和位移模态振型,根据模态置信准则、转换矩阵稳定性和模态振型相似性分别设计了三... 通过优化光纤布拉格光栅形状传感技术中传感点位置和补偿重构结果来提高薄层合金板三维形状重构精度。通过ANSYS workbench建立合金板仿真模型,提取应变和位移模态振型,根据模态置信准则、转换矩阵稳定性和模态振型相似性分别设计了三个目标函数,采用快速和精英机制的多目标遗传算法优化传感器位置。将镍钛合金板弯曲成不同曲率半径的弧形,利用光纤布拉格光栅中心波长漂移量和线性插值算法计算得出不同形状下的结构应变,重构合金板形状,均方根误差和最大误差相较于单目标优化算法分别减小30%和15%。利用粒子群优化径向基函数神经网络算法拟合误差与位移的关系实现误差补偿,均方根误差和最大误差比无补偿时分别减小了90%和70%,最大相对百分比误差仅为5%,提高了三维形状重构算法精度。 展开更多
关键词 光纤传感 光纤布拉格光栅 粒子群优化径向基函数 形状重构 模态法 多目标优化 误差补偿
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氨基化-多壁碳纳米管QuEChERS-液相色谱-串联质谱法测定热带水果中110种农药及其代谢物残留量 被引量:2
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作者 潘永波 张妙宜 +2 位作者 万娜 王彬 潘灿平 《农药学学报》 CAS CSCD 北大核心 2024年第1期189-202,共14页
建立基于氨基化-多壁碳纳米管(amino-functionalized multi-walled carbon nanotubes,NH2-MWCNTs)改进的QuEChERS净化方法,结合液相色谱-串联质谱(LC-MS/MS)测定3种热带水果中110种农药及其代谢物残留量。样品经乙腈提取,采用欧洲标准(E... 建立基于氨基化-多壁碳纳米管(amino-functionalized multi-walled carbon nanotubes,NH2-MWCNTs)改进的QuEChERS净化方法,结合液相色谱-串联质谱(LC-MS/MS)测定3种热带水果中110种农药及其代谢物残留量。样品经乙腈提取,采用欧洲标准(EN.15662)萃取缓冲体系QuEChERS盐包提取,NH2-MWCNTs改良的分散固相萃取(d-SPE)净化管净化,多反应监测模式(MRM)分析,基质匹配标准曲线外标法定量。结果表明:在0.002~0.2 mg/L范围内110种农药及其代谢物具有良好的线性关系,决定系数(R2)均高于0.9902,定量限(LOQ)为0.005~0.05 mg/kg,添加回收率为61%~120%,相对标准偏差(RSD)为0.30%~15%(n=6)。该方法净化效果好,能在短时间内可靠地分析样品。灵敏度、正确度、精密度均满足日常检测定性、定量需求,适用于荔枝、龙眼和香蕉等热带水果中农药多残留的快速检测。 展开更多
关键词 氨基化-多壁碳纳米管 QUECHERS 液相色谱-串联质谱 热带水果 农药多残留
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