检索结果-内蒙古大学图书馆

Astragalus polysaccharides combined with simvastatin as an immunostimulant enhances the immune adjuvanticity of oil-in-water emulsion and immune responses in mice

引用

VACCINE 2023年第10期41卷 1684-1693页

作者： xu, shuwen Wu, Zhiyong Cai, Gaofeng Zhang, Yue Peng, Song Jiao, Lina Liu, Zhenguang Yang, Yang Wang, Deyun Coll Vet Med Inst Tradit Chinese Vet Med Nanjing 210095 Jiangsu Peoples R China Nanjing Agr Univ Coll Vet Med MOE Joint Int Res Lab Anim Hlth & Food Safety Nanjing 210095 Jiangsu Peoples R China Nanjing Tradit Chinese Vet Med Res Ctr Nanjing 210095 Jiangsu Peoples R China

Oil-in-water emulsion-based adjuvants have demonstrated acceptable safety in many disease indica-tions, while their adjuvant activities for vaccines still need to be improved. Recently, the strategy of com-bining adjuvants with multiple types of immunostimulants has been shown to enhance immune responses. In this study, astragalus polysaccharides were combined with simvastatin as an immunostim-ulant to construct a compound O/W emulsion adjuvant. The formulations were optimized according to the OVA-specific antibody responses induced in mice. For this reason, high (5 mg/mL), medium (2.5 mg/mL), and low (1.25 mg/mL) concentrations of astragalus polysaccharides and high (10 mg/mL), medium (1 mg/mL), and low (0.1 mg/mL) concentrations of simvastatin were selected. The final optimal formulation of the immunostimulant was a high concentration of astragalus polysaccharides combined with a medium concentration of simvastatin. The optimal compound O/W emulsion adjuvant could induce effective humoral and cellular immune responses that were stronger and more stable than those induced by aluminum adjuvant and Freund's adjuvant. The OVA/HAPS-MSim-OE induced dramatically strong and persistent IgG expressions and Th1-polarized immune responses. What's more, the highest CD4+/CD8+lymphocyte ratios were observed in OVA/HAPS-MSim-OE group. In addition, compound O/ W emulsion adjuvant groups significantly promoted the secretion of IFN-c and IL-6, which also indicated that the compound O/W emulsion adjuvants could induce both enhanced Th1 and Th2-mediated immune responses but prefer the Th1-mediated ones. This study would contribute to an interesting and promising direction in the development of emulsion-based adjuvants. (c) 2023 Elsevier Ltd. All rights reserved.

关键词： Astragalus polysaccharides Simvastatin O W emulsion Ovalbumin Adjuvant

来源：评论

学校读者我要写书评

暂无评论

Special Section on Radar Detection and Interference Suppression

引用

Journal of Systems Engineering and Electronics 2024年第1期35卷 1-1页

作者： Wang, xuesong Cui, Guolong xu, shuwen Yang, Yong NUDT China College of Electronic Science China National Laboratory of Radar Signal Processing Xidian University China School of Electronic Science National University of Defense Technology China

来源：评论

学校读者我要写书评

暂无评论

基于标签传播算法的海面漂浮小目标检测方法

引用

电子与信息学报 2022年第6期44卷 2119-2126页

作者：许述文茹宏涛西安电子科技大学雷达信号处理国家重点实验室西安710071

在高分辨体制下海杂波与海面小目标具有复杂的特性,特别是对于雷达散射截面积较小的海面漂浮目标,传统的检测方法性能不佳。为了突破临界信杂比情况下的检测性能,可以提取雷达回波的一种或者多种特征,从而进行特征检测,该方法是实现临... 详细信息

在高分辨体制下海杂波与海面小目标具有复杂的特性,特别是对于雷达散射截面积较小的海面漂浮目标,传统的检测方法性能不佳。为了突破临界信杂比情况下的检测性能,可以提取雷达回波的一种或者多种特征,从而进行特征检测,该方法是实现临界信杂比情况下有效检测的重要途经。目前,在3维及以下的特征空间中可以使用凸包学习算法计算判决区域并有效地控制虚警概率,但是在3维以上的特征空间中凸包学习算法计算复杂度提高,难以进行检测。针对这个问题,该文提出一种基于标签传播算法的海面小目标检测方法,它突破了凸包学习算法的维数限制和决策域必须为凸集的形状限制,能够在高维特征空间进行检测并有效地控制虚警。经过实测数据集验证,基于标签传播算法的海面小目标检测方法在0.512 s和1.024 s的观测时间内分别获得了88.4%和92.0%的检测概率,相比于基于K近邻(KNN)的检测器有了3.3%和2.8%的检测概率提升。

关键词：高分辨海杂波特征检测标签传播算法可控虚警

来源：评论

学校读者我要写书评

暂无评论

Knowledge-Aided Adaptive Gradient Test for Radar Targets in Correlated Compound Gaussian Sea Clutter With Lognormal Texture

引用

IEEE GEOSCIENCE AND REMOTE SENSING LETTERS 2023年 20卷 1页

作者： xue, Jian Yan, Jiali Pan, Meiyan xu, shuwen Xian Univ Posts & Telecommun Sch Commun & Informat Engn Xian 710121 Peoples R China Xian Univ Posts & Telecommun Sch Artificial Intelligence Xian 710121 Peoples R China Xian Elect Engn Res Inst Xian 710100 Peoples R China Xidian Univ Natl Lab Radar Signal Proc Xian 710071 Peoples R China

This letter deals with the knowledge-aided adaptive detection problem of radar targets in nonhomogeneous correlated compound Gaussian sea clutter. The lognormal distribution is used as the prior distribution of the clutter texture to match the non-Gaussianity of sea clutter. In addition, in order to ensure the estimation accuracy of the covariance matrix structure of sea clutter, a convex combination estimator (CCE) is proposed by jointly exploiting the prior information and the current secondary data. Then, a knowledge-aided adaptive detector is designed on the basis of the complex parameter Gradient test and the CCE. Numerical experiments verify the effectiveness of the proposed CCE and adaptive detector in comparison with their counterparts, respectively.

关键词： Compound Gaussian sea clutter convex combination estimator (CCE) covariance matrix structure knowledge-aided

来源：评论

学校读者我要写书评

暂无评论

基于WGAN-GP-CNN的海面小目标检测

引用

信号处理 2024年第6期40卷 1082-1097页

作者：时艳玲陶平许述文南京邮电大学通信与信息工程学院江苏南京210003 西安电子科技大学雷达信号处理全国重点实验室陕西西安710071

针对传统基于统计理论的海面小目标检测方法在复杂海面环境中性能不高的问题,该文提出了一种改进的检测方法。首先通过分析海杂波和目标回波的特征,将检测问题转化为特征空间的分类任务。鉴于海面小目标样本数量有限,存在样本不平衡的问... 详细信息

针对传统基于统计理论的海面小目标检测方法在复杂海面环境中性能不高的问题,该文提出了一种改进的检测方法。首先通过分析海杂波和目标回波的特征,将检测问题转化为特征空间的分类任务。鉴于海面小目标样本数量有限,存在样本不平衡的问题,该文引入了一种基于梯度惩罚的沃瑟斯坦生成对抗网络(Wasserstein Generative Adversarial Network with Gradient Penalty,WGAN-GP)来增强目标数据,从而在数量上平衡目标样本与海杂波样本。同时,对原始WGAN-GP网络的损失函数进行了改进,引入相位损失以确保生成数据能够反映真实数据的相位信息。基于这些数据,进一步提取了生成目标和海杂波的高维特征,并将其送入卷积神经网络(Convolutional Neural Network,CNN)进行训练。为了应对高维特征空间中虚警概率难以控制的问题,对CNN算法进行了改进,通过设置Softmax分类器的阈值,实现了虚警概率可控。最后,借助公开的IPIX雷达数据集进行实验验证,所提的WGAN-GP-CNN检测器在积累时间为1.024 s,虚警概率为0.001时,平均检测概率达到0.8683,具有良好的检测效果。

关键词：海杂波小目标检测虚警可控生成对抗网络卷积神经网络

来源：评论

学校读者我要写书评

暂无评论

Sea-Land Segmentation Algorithm Based on Multiframe Radar Echoes

引用

IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 2023年 61卷 1页

作者： xu, shuwen Bai, Xiaohui Ren, Qinghui Li, Dongchen Xidian Univ Natl Key Lab Radar Signal Proc Xian 710071 Peoples R China Syst Engn Res Inst Beijing 100096 Peoples R China

In modern radar applications, data-driven sea-land segmentation of complex environments based directly on radar returns without the help of electronic charts and other information has attracted researchers' attention due to the solidification of exogenous information and defect of nonreal timeness. However, the sea-land segmentation based on radar echoes still faces two problems: first, complex clutter environment with mixed ground and sea clutter leads to a large dynamic range of clutter power, which makes power-based segmentation unreliable;and second, stable segmentation features are difficult to obtain when echoes in a single scan period are limited. In the case of multiframe radar echoes, this article first unwraps the phases of two adjacent echo sequences and extracts a new similarity measure for sea-land segmentation based on the covariance of phase difference sequences between sea clutter and ground clutter. Then, inspired by the idea of iteration, this article proposes a method to iterate the covariance matrix by iterating the clutter map of the characteristic differences of multiframe echoes to distinguish between sea and ground clutter more effectively. Experimental results based on the measured data show that the proposed sea-land segmentation method based on multiframe echoes can effectively separate sea and land areas and ensure the quality of the segmentation results, and after several consecutive scan periods, the proposed sea-land segmentation method is more accurate and robust than other sea-land segmentation methods.

关键词： Clutter Radar Radar clutter Image segmentation Spaceborne radar Radar imaging Object detection Clutter map multiframe radar echoes sea clutter sea-land segmentation

来源：评论

学校读者我要写书评

暂无评论

Theory and Design of Joint Time-Vertex Nonsubsampled Filter Banks

引用

IEEE TRANSACTIONS ON SIGNAL PROCESSING 2021年 69卷 1968-1982页

作者： Jiang, Junzheng Feng, Hairong Tay, David B. xu, shuwen Guilin Univ Elect Technol Sch Informat & Commun Guilin 541004 Peoples R China Natl & Local Joint Engn Res Ctr Satellite Nav Pos Guilin 541004 Peoples R China Deakin Univ Sch Informat Technol Waurn Ponds Vic 3216 Australia Xidian Univ Natl Lab Radar Signal Proc Xian 710071 Peoples R China

Graph signal processing (GSP) is a field that deals with data residing on irregular domains, i.e. graph signals. In this field, the graph filter bank is one of the most important developments, owing to its ability to provide multiresolution analysis of graph signals. However, most of the current research on graph filter bank focuses on static graph signals. The research does not exploit the temporal correlations of time-varying signals in real-world applications, such as in wireless sensor networks. In this paper, the theory and design of joint time-vertex nonsubsampled filter bank are developed, using a generalized product graph framework. Several methods are proposed to design the filter bank with perfect reconstruction, while still achieving filters with good spectral characteristics. A notable feature of the designed filter bank is that it can be completely realized in a distributed manner. The subband filters are either of polynomial type or defined implicitly via iterative equations. In either case, implementing the subband filters requires only the exchange of information between neighboring nodes. The filter banks are therefore of low implementation complexity and suitable for processing large time-varying datasets. Numerical examples will demonstrate the effectiveness of the proposed designed methods. Application in time-varying graph signal denoising will show the superiority of joint time-vertex filter bank over other methods.

关键词： Signal processing Laplace equations Two dimensional displays Spectral analysis Wireless sensor networks Topology Noise reduction Graph signal processing graph filter bank generalized product graph framework joint time-vertex filter bank distributed processing denoising

来源：评论

学校读者我要写书评

暂无评论

基于N-K和SNA的高层住宅火灾事故风险因素分析及控制

引用

防灾减灾工程学报 2025年第1期45卷 128-136,178页

作者：武乾杨建宏徐树文西安建筑科技大学土木工程学院陕西西安710055

高层住宅火灾安全防控是一个复杂系统问题,从系统层面确定其风险耦合形式及关键风险因素对提升我国高层住宅消防安全水平具有重要意义。为分析高层住宅火灾事故风险因素并提出防控策略,通过收集2015~2023年我国发生的162起高层住宅火灾... 详细信息

高层住宅火灾安全防控是一个复杂系统问题,从系统层面确定其风险耦合形式及关键风险因素对提升我国高层住宅消防安全水平具有重要意义。为分析高层住宅火灾事故风险因素并提出防控策略,通过收集2015~2023年我国发生的162起高层住宅火灾较大事故案例,结合专家访谈和已有的事故致因分类模型,将高层住宅火灾事故风险因素分为5类一级风险因素和26个二级风险因素;基于N-K模型求解出风险因素耦合值,将风险耦合形式量化并进行耦合致险性评价;利用社会网络分析(Social Network Analysis,SNA)可视化风险因素间的作用关系,分析其中心度和可达性,挖掘出风险因素的发展态势和诱发其他风险因素出现的可能性;结合N-K和SNA对各风险节点的出度进行修正,确定高层住宅火灾事故的关键风险因素。结果表明:多风险因素耦合导致事故发生的概率较大;火灾事故的起因在较大程度上是居民方的原因,开发商、物业、社区、监管单位四方的风险易使灾情扩大、程度升级;防控开发商-监管单位两风险因素耦合可有效避免事故发生;开发商、社区、监管单位风险因素的出现易连通各风险节点,引发耦合效应;从开发商、物业、社区及监管单位角度出发进行防控是重点。

关键词：安全工程高层住宅火灾事故 N-K模型社会网络分析风险耦合

来源：评论

学校读者我要写书评

暂无评论

Persymmetric Detection of Radar Targets in Nonhomogeneous and Non-Gaussian Sea Clutter

引用

IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 2022年 60卷 1页

作者： xue, Jian xu, shuwen Liu, Jun Xian Univ Posts & Telecommun Sch Commun & Informat Engn Xian 710121 Peoples R China Xidian Univ Natl Lab Radar Signal Proc Xian 710071 Peoples R China Xidian Univ Collaborat Innovat Ctr Informat Sensing & Underst Xian 710071 Peoples R China Univ Sci & Technol China Dept Elect Engn & Informat Sci Hefei 230026 Peoples R China

This article addresses the detection problem of radar targets embedded in nonhomogeneous and non-Gaussian sea clutter. Nonhomogeneity leads to insufficiency of secondary data for estimating the clutter speckle covariance matrix, and non-Gaussianity causes sea clutter to become spiky. In this article, the persymmetry of the clutter covariance matrix is adopted to alleviate the requirement of secondary data, and the prior distribution of clutter texture is exploited to tackle the clutter non-Gaussianity. Based on such clutter knowledge, three adaptive detectors are proposed according to the principles of the generalized likelihood ratio test, the Wald test, and the Rao test. It is proven that three detectors ensure constant false alarm rate (CFAR) properties with respect to both the clutter speckle covariance matrix and the clutter power mean. Simulation experiments show that three detectors outperform their competitors.

关键词： Clutter Detectors Covariance matrices Speckle Radar clutter Radar Radar detection Non-Gaussian nonhomogeneous persymmetric detection radar targets sea clutter

来源：评论

学校读者我要写书评

暂无评论

Polarimetric Adaptive Radar Target Detection in Sea Clutter with Lognormal Texture

SSRN

引用

SSRN 2024年

作者： xue, Jian Yan, Jiali xu, shuwen Liu, Jun School of Communications and Information Engineering Xi’an University of Posts and Telecommunications Xi’an710121 China National Laboratory of Radar Signal Processing and Collaborative Innovation Center of Information Sensing and Understanding Xidian University Xi’an710071 China Department of Electronic Engineering and Information Science University of Science and Technology of China Hefei230027 China

This paper addresses the problem of polarimetric adaptive coherent detection for maritime radar targets in the non-Gaussian sea clutter background. First, the radar sea clutter data at multiple polarimetric channels are modelled using the compound Gaussian model with an unknown speckle covariance matrix and a lognormal-distributed texture. Then, three adaptive polarimetric coherent detectors are derived based on estimation of unknown parameters and the two-step versions of generalized likelihood ratio test (GLRT), complex parameter Rao and Wald tests. All the proposed detectors exploit the clutter texture distribution information and the polarimetric information of radar data to enhance the detection performance. Finally, simulation experiments on simulated and measured radar data are utilized to evaluate the performance of the proposed detectors. The experimental results indicate that three proposed detectors outperform their competitors, and that their performance is affected by polarimetric channel parameters, i.e., the number of secondary data, the correlation of target signal or clutter speckle, the difference of signal-to-clutter ratio. Moreover, the proposed detectors approximately exhibit the constant false alarm rate property in relation to the average clutter power and the speckle covariance matrix. © 2024, The Authors. All rights reserved.

关键词： Textures

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：