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Well-posedness and dynamics of fractional Fitz Hugh-Nagumo systems on R^(N) driven by nonlinear noise

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Science China Mathematics 2021年第11期64卷 2395-2436页

作者： Renhai wang Boling Guo bixiang wang Institute of Applied Physics and Computational Mathematics Beijing 100088China Department of Mathematics New Mexico Institute of Mining and TechnologySocorroNM 87801USA

This article is concerned with the well-posedness as well as long-term dynamics of a wide class of non-autonomous,non-local,fractional,stochastic Fitz Hugh-Nagumo systems driven by nonlinear noise defined on the entire space *** well-posedness is proved for the systems with polynomial drift terms of arbitrary order as well as locally Lipschitz nonlinear diffusion terms by utilizing the pathwise and mean square uniform *** mean random dynamical system generated by the solution operators is proved to possess a unique weak pullback mean random attractor in a Bochner *** existence of invariant measures is also established for the autonomous systems with globally Lipschitz continuous diffusion *** idea of uniform tail-estimates of the solutions in the appropriate spaces is employed to derive the tightness of a family of probability distributions of the solutions in order to overcome the non-compactness of the standard Sobolev embeddings on RNas well as the lack of smoothing effect on one component of the *** results of this paper are new even when the fractional Laplacian is replaced by the standard Laplacian.

关键词： fractional Fitz Hugh-Nagumo system weak pullback mean random attractor invariant measure nonlinear noise unbounded domain

基于改进YOLOv5的船舶多尺度SAR图像检测算法

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数据采集与处理 2024年第1期39卷 120-131页

作者：李生辉李晓飞宋璋晗王必祥南京邮电大学宽带无线通信技术教育部工程研究中心南京210003

针对复杂场景下合成孔径雷达(Synthetic aperture radar, SAR)图像船舶目标像素尺度差异大和船舶密集排列造成目标漏检的问题,提出一种基于改进YOLOv5的船舶多尺度SAR图像检测算法。对于YOLOv5的颈部网络,采用双向特征金字塔结构(Bi-dir... 详细信息

针对复杂场景下合成孔径雷达(Synthetic aperture radar, SAR)图像船舶目标像素尺度差异大和船舶密集排列造成目标漏检的问题,提出一种基于改进YOLOv5的船舶多尺度SAR图像检测算法。对于YOLOv5的颈部网络,采用双向特征金字塔结构(Bi-directional feature pyramid network, BiFPN)提升网络多尺度特征融合能力,并在其自下而上的特征融合支路中,基于深度可分离卷积(Depthwise separable convolution, DSC)和通道MLP构建EC-MLP(Enhanced channel-MLP)模块,从而丰富语义信息,提供更充分的船舶目标上下文特征;引入全局注意力机制(Global attention mechanism, GAM),使网络对输入特征进行针对性提取并运算,减少网络的信息丢失;此外,使用SIoU损失函数进一步提高网络的训练收敛速度和检测精度。在SSDD和HRSID数据集上与其他8种方法(Faster R-CNN、Libra R-CNN、FCOS、YOLOv5s、PP-YOLOv2、YOLOX-s、PP-YOLOE-s和YOLOv7-tiny)进行对比实验。实验结果表明:改进后算法在SSDD数据集上的AP50达到了96.7%,在HRSID数据集上AP50达到了95.6%,优于对比方法。

关键词：合成孔径雷达船舶目标检测双向特征金字塔网络深度可分离卷积全局注意力机制

Global existence theory for the two-dimensional derivative Ginzburg-Landau equation

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Chinese Science Bulletin 1998年第5期43卷 393-395页

作者： Zhenchao Cao Boling Guo bixiang wang Xiamen Univ Math Inst Xiamen 361005 Peoples R China Inst Appl Phys & Computat Math Beijing 100088 Peoples R China

The generalized derivative Ginzburg-Landau equation in two spatial dimensions is discussed. The existence and uniqueness of global solution are obtained by Galerkin method and by a priori estimates on the solution in ... 详细信息

关键词： Ginzburg-Landau equation global existence.

Effects of dietary fiber on human health

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Food Science and Human Wellness 2022年第1期11卷 1-10页

作者： Yang He bixiang wang Liankui Wen Fengzhong wang Hansong Yu Dongxia Chen Xin Su Chi Zhang Institute of Food Science and Technology Chinese Academy of Agricultural Sciences(CAAS)Beijing 100193China Department of Food Science and Engineering Jilin Agricultural UniversityChangchun 130118China Division of Soybean Processing Soybean Research&Development CenterChinese Agricultural Research SystemChangchun 130118China

Dietary fiber(DF)is believed to provide important health benefits and it has become a research *** exists in most natural foods,including fruits(16.74%-91.24%),vegetables(6.53%-85.19%),grains(9.76%-69.20%)and so *** has different physicochemical properties such as water holding capacity(WHC)(2.01-25.03 g/g),water swelling capacity(WSC)(0.95-23.90 mL/g),oil holding capacity(OHC)(0.65-29.00 g/g),glucose adsorption capacity(GAC)(0.17-4.65 mmol/g),cholesterol adsorption capacity(CAC)(0.03-37.10 mg/g)and viscosity,which make it exhibits different physiological functions such as reducing the risk of obesity,diabetes,cancer,and intestinal *** the basis of consulting related databases,the physicochemical properties of DF and its derived physiological functions are *** is found that DF has effect on the prevention and treatment of obesity due to good WHC,WSC,OHC and *** GAC can relieve the symptoms of *** physicochemical properties of WHC and WSC can reduce the risk of *** WHC,WSC and viscosity are beneficial to intestinal health.

关键词： Dietary fiber Physicochemical properties Human health

Geochemical Characteristics of Granitoids in the Eastern Sector of the Northern Tianshan Mountains in Xinjiang

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Acta Geologica Sinica(English Edition) 1990年第1期64卷 55-67页

作者： wang bixiang Li Zhaonai Zhao Guangzan wang Fubao Zhang Shuizhe Fei Wenheng Institute of Geology, Chinese Academy of Geological Sciences, Beijing Institute of Geology Chinese Academy of Geological Sciences Beijing

The granitioids in question are located in the geosynclinal fold belt of the Northern Tianshan Mountains.The magmas are intruded into a Carboniferous marine volcanic-sedimentary rock series. forming a contempo-raneous. intermediate-basic to acid. composite intrusion. With a whole-rock Rb-Sr isochron age of 315.7 Ma. itis considered to be of middle Heicynian age. The granitoids have a SiO_2 content of 48-78%, a calc-alkali indexof 60 and silica-alkali indices ρ=2.2-2.4 and σ=1.5-2. From basic to acid compositions, the total REE con-tent increases from 38 to 143 ppm. δEu ranges from 0.47 to 0.86 and the Eu anomalies are negative. Thenormalized curves of REE of various rock types are very similar. These coupled with the characteristics of traceelement geochemistry show that the intrusion is an island arc-continental margin, calc-alkaline one. Theδ^(18)O values range from 5.8 to 8.9‰ and the ^(87)Sr/^(86)Sr initial ratio is 0.705. The materials of the intrusion arecomposed of a mixture of the magmas at the top of the upper mantle and in the lower crust, This indicates thatthe rocks might be consanguineous. differentiated and evolved products and possess the characteristics of Ⅰtype granites.

关键词： Geochemical Characteristics of Granitoids in the Eastern Sector of the Northern Tianshan Mountains in Xinjiang

MELT AND FLUID INCLUSIONS IN IGNEOUS ROCKS IN CENTRAL XIZANG (TIBET)

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Science in China,Ser.B 1986年第7期29卷 771-784页

作者：王碧香 Institute of Geology Chinese Academy of Geological Sciences Beijing

Through a study of the characteristics and composition of melt and fluid inclusions in volcanic rocks and their associated granites in the subduction zone of the Tibetan plate, it has been found that the characteristics of the inclusions in quite a few minerals of various rock types are closely related to the nature of molten magmas, thickness of strata and cooling speed. Therefore, their characteristics may be used to discriminate different lithofacies types. In this paper the evolution and crystallization of magmas are discussed on the basis of the glass composition of the inclusions measured using the electron probe, and the gas composition and its parameters are used in elucidating the physico-chemical conditions of rock and ore formation.

关键词： TIBET MELT AND FLUID INCLUSIONS IN IGNEOUS ROCKS IN CENTRAL XIZANG

On the construction of Approximate Inertial Manifolds

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Journal of Mathematical Research with Applications 1995年第3期 367-368页

作者： wang bixiang(Dept. of Math., Lanzhou University, Lanzhou 730000)

ＯｎｔｈｅＣｏｎｓｔｒｕｃｔｉｏｎｏｆＡｐｐｒｏｘｉｍａｔｅＩｎｅｒｔｉａｌＭａｎｉｆｏｌｄｓＷａｎｇＢｉｘｉａｎｇ（Ｄｅｐｔ．ｏｆＭａｔｈ．，ＬａｎｚｈｏｕＵｎｉｖｅｒｓｉｔｙ，Ｌａｎｚｈｏｕ７３００００）Ｏｎｔｈ... 详细信息

ＯｎｔｈｅＣｏｎｓｔｒｕｃｔｉｏｎｏｆＡｐｐｒｏｘｉｍａｔｅＩｎｅｒｔｉａｌＭａｎｉｆｏｌｄｓＷａｎｇＢｉｘｉａｎｇ（Ｄｅｐｔ．ｏｆＭａｔｈ．，ＬａｎｚｈｏｕＵｎｉｖｅｒｓｉｔｙ，Ｌａｎｚｈｏｕ７３００００）ＯｎｔｈｅＣｏｎｓｔｒｕｃｔｉｏｎｏｆＡｐ...

关键词： contraction principle approximate inertial manifold reaction diffusion equa-tion.

UpperSemicontinuityofAtractorsfortheReactionDifusionEquation

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Communications in Nonlinear Science and Numerical Simulation 1996年第2期 40-43页

作者： Boling GUO & bixiang wang (Institute of Applied Physics and Computational Mathematics, P. O. Box 8009, Beijing 100088, P. R. China)

ＵｐｐｅｒＳｅｍｉｃｏｎｔｉｎｕｉｔｙｏｆＡｔｒａｃｔｏｒｓｆｏｒｔｈｅＲｅａｃｔｉｏｎＤｉｆｕｓｉｏｎＥｑｕａｔｉｏｎ１ＢｏｌｉｎｇＧＵＯ＆ＢｉｘｉａｎｇＷＡＮＧ（ＩｎｓｔｉｔｕｔｅｏｆＡｐｐｌｉｅｄＰｈｙｓｉｃｓ... 详细信息

ＵｐｐｅｒＳｅｍｉｃｏｎｔｉｎｕｉｔｙｏｆＡｔｒａｃｔｏｒｓｆｏｒｔｈｅＲｅａｃｔｉｏｎＤｉｆｕｓｉｏｎＥｑｕａｔｉｏｎ１ＢｏｌｉｎｇＧＵＯ＆ＢｉｘｉａｎｇＷＡＮＧ（ＩｎｓｔｉｔｕｔｅｏｆＡｐｐｌｉｅｄＰｈｙｓｉｃｓａｎｄＣｏｍｐｕｔａｔｉｏｎａｌＭ...

关键词： AMS

随机时滞Schrodinger格系统的不变测度

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中国科学：数学 2022年第9期52卷 1015-1032页

作者：陈章王碧祥杨莉山东大学数学学院济南250100 Department of Mathematics New Mexico Institute of Mixing and TechnologySocorroNM 87801USA

本文研究随机时滞Schrodinger格系统,其漂移和扩散系数是局部Lipschitz连续的.首先,建立一些解的一致估计,包括高阶矩估计和一致尾端估计.其次,运用Arzelà-Ascoli定理和二分法技巧证明解的概率分布族在空间C([-ρ,0];l^(2))中的胎紧性... 详细信息

本文研究随机时滞Schrodinger格系统,其漂移和扩散系数是局部Lipschitz连续的.首先,建立一些解的一致估计,包括高阶矩估计和一致尾端估计.其次,运用Arzelà-Ascoli定理和二分法技巧证明解的概率分布族在空间C([-ρ,0];l^(2))中的胎紧性.最后,利用Krylov-Bogolyubov方法证明系统Markov半群不变测度的存在性.

关键词：不变测度随机离散Schrodinger方程非线性噪声时滞尾端估计