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A multispectral image compression and encryption algorithm based on tensor decomposition and chaos

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High Technology Letters 2022年第2期28卷 134-141页

作者： XU Dongdong du limin Electronin Information Engineering College Changchun UniversityChangchun 130022P.R.China

A multi spectral image compression and encryption algorithm that combines Karhunen-Loeve(KL) transform,tensor decomposition and chaos is proposed for solving the security problem of multi-spectral image compression and ***,in order to eliminate residual spatial redundancy and most of the spectral redundancy,the image is performed by KL ***,to further eliminate spatial redundancy and reduce block effects in the compression process,two-dimensional discrete 9/7 wavelet transform is performed,and then Arnold transform and encryption processing on the transformed coefficients are ***,the tensor is decomposed to keep its intrinsic structure intact and eliminate residual space ***,differential pulse filters are used to encode the coefficients,and Tent mapping is used to implement confusion diffusion encryption on the code *** experimental results show that the method has high signal-to-noise ratio,fast calculation speed,and large key space,and it is sensitive to keys and plaintexts with a positive effect in spectrum assurance at the same time.

关键词： Karhunen-Loeve(KL)transform tensor decomposition differential pulse filter Tent map

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汽车型面语义设计与光影解构

时代汽车 2024年第11期 109-111页

作者：李超杜丽敏易康比亚迪汽车工业有限公司汽车工程研究院高级曲面设计部广东深圳518118

“流光塑影,赋形达意”是对汽车造型意图表达的最高诠释,造型意图表现形式分为型面语义和光影表达,型面语义涵盖了型面风格、断面关系、特征轮廓形态三大部分;光影的虚实及流动变化一定程度上反映了型面体量、特征饱满程度、主次协调关... 详细信息

“流光塑影,赋形达意”是对汽车造型意图表达的最高诠释,造型意图表现形式分为型面语义和光影表达,型面语义涵盖了型面风格、断面关系、特征轮廓形态三大部分;光影的虚实及流动变化一定程度上反映了型面体量、特征饱满程度、主次协调关系等视觉表征信息。型面表达是汽车造型设计的最终呈现形式,通过“找形”来塑造型面特征的丰富变化,推敲模型比例与姿态;利用“塑形”展现形态肌理和光影的高级感,潜移默化地演变成高辨识度的设计符号,最终形成具有情感语义的品牌基因。本文旨在通过对造型意图的表达方式-型面语义和光影解构的研究,提升A面设计的高级感和精致感,探究光影与型面的共生关系,形成具有技术参数意义的曲面设计策略。

关键词：型面语义光影形态肌理型面体量

全身振动训练改善脑卒中后跌倒风险的Meta分析

同方期刊数据库博看期刊评论

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黑龙江医学 2024年第18期48卷 2262-2266页

作者：杜利民徐刚刘建赵澎天津市儿童医院康复科天津300074

目的:系统评价全身振动训练对脑卒中后跌倒风险的临床疗效。方法:检索公开发表的关于全身振动训练治疗脑卒中后跌倒风险的随机对照试验文献,并用RevMan 5.4软件进行Meta分析。结果:研究共纳入21篇文献,共计1093例患者。经Meta分析发现,... 详细信息

目的:系统评价全身振动训练对脑卒中后跌倒风险的临床疗效。方法:检索公开发表的关于全身振动训练治疗脑卒中后跌倒风险的随机对照试验文献,并用RevMan 5.4软件进行Meta分析。结果:研究共纳入21篇文献,共计1093例患者。经Meta分析发现,与传统康复组相比,全身振动训练可以改善脑卒中后“起立-行走”计时测试(TUGT)[WMD=-1.77,95%CI(-2.69,-0.86),P=0.0001]、改良Ashworth量表(MAS)[WMD=-0.33,95%CI(-0.41,-0.25),P<0.0001]情况,而对于特异性活动平衡信心量表没有影响[WMD=1.14,95%CI(-1.99,4.27),P=0.48]。亚组分析显示,全身振动训练可显著改善脑卒中后亚急性期MAS评分[WMD=-0.38,95%CI(-0.47,-0.30),P<0.00001],而对后遗症期无明显改善[WMD=-0.08,95%CI(-0.26,0.10),P=0.36]。结论:全身振动训练对脑卒中后TUGT、痉挛有积极影响,有助于降低跌倒风险,而对跌倒恐惧心理无显著作用。在亚急性期进行全身振动训练,可能会更好地改善脑卒中后患者的痉挛障碍。

关键词：全身振动训练脑卒中偏瘫跌倒风险 Meta分析

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不同表型粗叶榕根部营养成分特征分析

分子植物育种 2024年第18期22卷 6138-6145页

作者：杜丽敏林旭俊杨丽薇黄国宁李晓斌郭霞海南省林业科学研究院(海南省红树林研究院) 海口571100

粗叶榕(Ficus hirta Vahl)具有复杂的遗传多样性,为了探究不同表型粗叶榕的差异,本研究以不同表型特征粗叶榕为研究对象,测定其根部不同营养物质、营养元素及氨基酸种类和含量特征,并比较不同表型与营养成分的关系。结果表明:三裂型粗... 详细信息

粗叶榕(Ficus hirta Vahl)具有复杂的遗传多样性,为了探究不同表型粗叶榕的差异,本研究以不同表型特征粗叶榕为研究对象,测定其根部不同营养物质、营养元素及氨基酸种类和含量特征,并比较不同表型与营养成分的关系。结果表明:三裂型粗叶榕根部总糖、粗蛋白、淀粉、补骨脂素含量均为最高,而七裂型粗叶榕根部粗蛋白、淀粉、补骨脂素、佛手柑内脂含量均为最低;三裂型粗叶榕根部Ca、Mn营养元素含量最高,而七裂型Mg、Cu营养元素含量最高,全缘型Fe元素含量最高,五裂型Sn元素含量最高;不同表型粗叶榕根部总氨基酸含量差异明显,其中三裂型总氨基酸含量和8种必需氨基酸含量均为最高,七裂型氨基酸总含量和必需氨基酸含量均为最低。从必需氨基酸与总氨基酸的占比来看,七裂型占比最高,不同表型粗叶榕根部必需氨基酸含量占比排序为:七裂型(2.15%)>五裂型(1.55%)>全缘型(1.33%)>三裂型(0.89%)。本研究为粗叶榕进一步开发利用提供理论依据。

关键词：粗叶榕营养元素氨基酸表型特征

电感耦合等离子体质谱法测定谷类产品中7种元素

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河南大学学报（自然科学版） 2024年第1期54卷 88-93页

作者：崔淑敏王通潘梦一李培洋张冠锡宋美荣李伟杜利敏河南农业大学理学院郑州450002 众平检测有限公司河南许昌461100 郑州市疾病预防控制中心郑州450007

为建立准确、快速地同时测定谷类产品中微量重金属元素含量的方法,采用电感耦合等离子体质谱法测定藜麦和绿豆芽等谷类产品中砷、镉、铅、锰、铜、锌和铁等7种微量重金属元素.以硝酸和双氧水消解样品,调谐优化仪器分析条件,锌、砷、铜... 详细信息

为建立准确、快速地同时测定谷类产品中微量重金属元素含量的方法,采用电感耦合等离子体质谱法测定藜麦和绿豆芽等谷类产品中砷、镉、铅、锰、铜、锌和铁等7种微量重金属元素.以硝酸和双氧水消解样品,调谐优化仪器分析条件,锌、砷、铜、锰和铁等5种元素选用KED模式,铅和镉选用STD模式,以标准曲线法进行测定.结果显示:砷、镉、铅、锰、铜、锌和铁的线性回归方程分别为y=1.49×10^(2)x+0、y=3.06×10^(2)x+0、y=1.0267×10^(4)x+0、y=1.029×10^(3)x+0、y=1.088×10^(3)x+0、y=2.67×10^(2)x+0和y=3.4×10^(1)x+0;砷、镉、铅、锰和铜的线性范围均为0.10~800.0μg·L^(-1),锌的线性范围为5.00~300.0μg·L^(-1),铁的线性范围为5.00~800.0μg·L^(-1),相关系数均在0.9994~0.9996之间;检出限在6.8×10^(-6)~2.6×10^(-2)mg·kg^(-1)之间;相对标准偏差(n=6)在0.26%~13.1%之间;回收率在89.2%~107%之间.该方法满足同时对藜麦和绿豆芽等谷类产品中砷、镉、铅、锰、铜、锌和铁等7种元素的快速准确测定.

关键词：电感耦合等离子体质谱法测定谷类产品微量重金属元素

Fabrication of micro spherulitic particles of carbamazepine-hesperetin cocrystal via QESD with enhanced manufacturability and dissolution

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PARTICUOLOGY 2024年第10期93卷 11-21页

作者： Ouyang, Jinbo Liu, Lishan Ning, Zichen Gong, Zhuoshan Zhou, limin He, Feiqiang Gao, Zhi Xu, Li du, Shichao Yang, Huaiyu East China Univ Technol Jiangxi Prov Key Lab Funct Organ Polymers Nanchang 330013 Peoples R China Qilu Univ Technol Sch Pharmaceut Sci Jinan 250353 Peoples R China Loughborough Univ Dept Chem Engn Loughborough LE11 3TU Leics England

Granulation is an effective method for improving the flowability of drugs, particularly when they are in needle form. Carbamazepine-hesperetin (CBZ-HPE) cocrystal is a needle-like crystal with low solubility and poor flowability, which limits its application. To address this issue, this study aimed to obtain CBZHPE microspheres using the quasi-emulsion solvent diffusion (QESD) technique. The preparation process was monitored using polarized light microscopy, and the formation mechanism was elucidated using the radial distribution function (RDF). The microspheres were extensively characterized using PXRD, DSC, TGA, and SEM. Furthermore, the effects of surfactants, contents, and rotational speeds on the morphology and particle size distribution of microspheres were analyzed to determine the optimal experimental conditions. Based on these findings, naringenin and quercetin, the active ingredients of traditional Chinese medicine, were chosen to successfully prepare CBZ-HPE multicomponent microspheres. This research provides a foundation for increasing drug powder properties and drug conjugation through the preparation of microspheres. (c) 2024 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

关键词： Carbamazepine-hesperetin cocrystal Quasi -emulsion solvent diffusion (QESD) technique Microspheres Flowability Dissolution rate SPHERICAL CRYSTALLIZATION AGGLOMERATION

Experimental Data-Driven Flow Field Prediction for Compressor Cascade based on Deep Learning and l_(1)Regularization

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Journal of Thermal Science 2024年第5期33卷 1867-1882页

作者： LIU Tantao GAO limin LI Ruiyu School of Power and Energy Northwestern Polytechnical UniversityXi'an 710012China School of Aerospace Engineering Xi'an Jiaotong UniversityXi'an 710049China

For complex flows in compressors containing flow separations and adverse pressure gradients,the numerical simulation results based on Reynolds-averaged Navier-Stokes(RANS)models often deviate from experimental measurements more or *** improve the prediction accuracy and reduce the difference between the RANS prediction results and experimental measurements,an experimental data-driven flow field prediction method based on deep learning and l_(1)regularization is proposed and applied to a compressor cascade flow *** inlet boundary conditions and turbulence model parameters are calibrated to obtain the high-fidelity flow *** Saplart-Allmaras and SST turbulence models are used independently for mutual *** contributions of key modified parameters are also analyzed via sensitivity *** results show that the prediction error can be reduced by nearly 70%based on the proposed *** flow fields predicted by the two calibrated turbulence models are almost the same and nearly independent of the turbulence *** corrections of the inlet boundary conditions reduce the error in the first half of the *** turbulence model calibrations fix the overprediction of flow separation on the suction surface near the tail edge.

关键词： experimental data-driven compressor cascade deep learning l_(1)regularization

cKBET:assessing goodness of batch effect correction for single-cell RNA-seq

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Frontiers of Computer Science 2024年第1期18卷 215-228页

作者： Yameng ZHAO Yin GUO limin LI School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China

Single-cell RNA sequencing reveals the gene structure and gene expression status of a single cell,which can reflect the heterogeneity between ***,batch effects caused by non-biological factors may hinder data integration and downstream *** the batch effect can be evaluated by visualizing the data,which actually is subjective and *** this work,we propose a quantitative method cKBET,which considers the batch and cell type information *** cKBET method accesses batch effects by comparing the global and local fraction of cells of different batches in different cell *** verify the performance of our cKBET method on simulated and real biological data *** experimental results show that our cKBET method is superior to existing methods in most *** general,our cKBET method can detect batch effect with either balanced or unbalanced cell types,and thus evaluate batch correction methods.

关键词： single-cell RNA-seq dataset b batch effect assessment cKBET method

A Grouped Scale-adaptive Phase-based Stereo Matching Method

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A Grouped Scale-adaptive Phase-based Stereo Matching Method