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同步辐射计算机断层技术衬度误差机理分析

物理学报 2006年第8期55卷 4065-4069页

作者：汪敏胡小方伍小平中国科学技术大学中国科学院材料力学行为和设计重点实验室合肥230027

基于同步辐射X射线的优越特性及计算机断层重建技术对材料无损检测等优点,同步辐射计算机断层重建技术已被广泛应用.对该技术衬度误差的形成机理及形式进行了分析研究,并给出了四种基本误差形式.数值模拟结果证实了分析的正确性.

关键词：同步辐射计算机断层衬度误差

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物体内部三维位移场分析的数字图像相关方法

物理学报 2006年第10期55卷 5135-5139页

作者：汪敏胡小方伍小平中国科学技术大学中国科学院材料力学行为和设计重点实验室合肥230026

提出了物体内部三维位移场的数字图像相关分析方法,对物体变形前后,或连续变形的两个相邻状态的内部三维结构的数字图像,通过相关运算获得三维位移场.文中给出了三维相关法的体搜索窗口、相关函数及亚像素运算的相关系数拟合函数.数字... 详细信息

提出了物体内部三维位移场的数字图像相关分析方法,对物体变形前后,或连续变形的两个相邻状态的内部三维结构的数字图像,通过相关运算获得三维位移场.文中给出了三维相关法的体搜索窗口、相关函数及亚像素运算的相关系数拟合函数.数字模拟结果证明了三维相关法的正确性及可靠性.位移计算精度为0·02像素.

关键词：数字图像相关三维相关亚像素

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电阻率二维神经网络反演

地球物理学报 2006年第2期49卷 584-589页

作者：徐海浪吴小平中国科学院壳幔物质与环境实验室

由于非线性特性地球物理反演一直以来都是一个比较困难的问题.近十年来,非线性反演方法如人工神经网络、遗传算法在地球物理数据解释中得到越来越多的应用,但目前基本仍限于一维反演问题.对于二维反问题,反演参数较多,神经网络反演运用... 详细信息

由于非线性特性地球物理反演一直以来都是一个比较困难的问题.近十年来,非线性反演方法如人工神经网络、遗传算法在地球物理数据解释中得到越来越多的应用,但目前基本仍限于一维反演问题.对于二维反问题,反演参数较多,神经网络反演运用较少.本文利用BP神经网络优化方法,实现了电阻率二维非线性反演.与传统线性化的迭代反演比较,神经网络反演能够克服传统方法的不足、获得更好的反演结果.

关键词：电阻率二维反演反向传播网络

Investigation of high rate mechanical flow followed by ignition for high-energy propellant under dynamic extrusion loading

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Defence Technology（防务技术） 2024年第2期32卷 336-347页

作者： Liying Dong Yanqing wu Kun Yang xiao Hou State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

Investigating the ignition response of nitrate ester plasticized polyether(NEPE) propellant under dynamic extrusion loading is of great significant at least for two cases. Firstly, it helps to understand the mechanism and conditions of unwanted ignition inside charged propellant under accident ***, evaluates the risk of a shell crevice in a solid rocket motor(SRM) under a falling or overturning scene. In the present study, an innovative visual crevice extrusion experiment is designed using a dropweight apparatus. The dynamic responses of NEPE propellant during extrusion loading, including compaction and compression, rapid shear flow into the crevice, stress concentration, and ignition reaction, have been firstly observed using a high-performance high-speed camera. The ignition reaction is observed in the triangular region of the NEPE propellant sample above the crevice when the drop weight velocity was 1.90 m/s. Based on the user material subroutine interface UMAT provided by finite element software LS-DYNA, a viscoelastic-plastic model and dual ignition criterion related to plastic shear dissipation are developed and applied to the local ignition response analysis under crevice extrusion conditions. The stress concentration occurs in the crevice location of the propellant sample, the shear stress is relatively large, the effective plastic work is relatively large, and the ignition reaction is easy to occur. When the sample thickness decreases from 5 mm to 2.5 mm, the shear stress increases from 22.3 MPa to 28.6 MPa, the critical value of effective plastic work required for ignition is shortened from 1280 μs to 730 μs, and the triangular area is easily triggering an ignition reaction. The propellant sample with a small thickness is more likely to stress concentration, resulting in large shear stress and effective work, triggering an ignition reaction.

关键词： NEPE propellant Crevice extrusion Shear flow Sample thickness Ignition reaction

Optimal proportioning of iron ore in sintering process based on improved multi-objective beluga whale optimisation algorithm

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Journal of Iron and Steel Research International 2024年第7期31卷 1597-1609页

作者： Zong-ping Li Xu-dong Li Xue-tong Yan wu Wen xiao-xin Zeng Rong-jia Zhu Ya-hui Wang Ling-zhi Yi Zhongye Changtian International Engineering Co. Ltd.Changsha 410205HunanChina College of Automation and Electronic Information Xiangtan UniversityXiangtan 411105HunanChina College of Electrical and Information Engineering Hunan UniversityChangsha 410082HunanChina

Proportioning is an important part of sintering,as it affects the cost of sintering and the quality of sintered *** address the problems posed by the complex raw material information and numerous constraints in the sintering process,a multi-objective optimisation model for sintering proportioning was established,which takes the proportioning cost and TFe as the optimisation ***,an improved multi-objective beluga whale optimisation(IMOBWO)algorithm was proposed to solve the nonlinear,multi-constrained multi-objective optimisation *** algorithm uses the con-strained non-dominance criterion to deal with the constraint problem in the ***,the algorithm employs an opposite learning strategy and a population guidance mechanism based on angular competition and two-population competition strategy to enhance convergence and population *** actual proportioning of a steel plant indicates that the IMOBWO algorithm applied to the ore proportioning process has good convergence and obtains the uniformly distributed Pareto ***,compared with the actual proportioning scheme,the proportioning cost is reduced by 4.3361¥/t,and the TFe content in the mixture is increased by 0.0367%in the optimal compromise ***,the proposed method effectively balances the cost and total iron,facilitating the comprehensive utilisation of sintered iron ore resources while ensuring quality assurance.

关键词： Sintering process Proportioning Iron ore Multi-objective beluga whale optimisation algorithm Proportioning cost

基于矩阵操作的必然性QoS约束副本放置方法

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系统工程理论与实践 2012年第12期32卷 2796-2801页

作者：付伟叶清吴晓平海军工程大学信息安全系武汉430033

如何提供严格有保障的数据服务质量,为每个数据访问请求提供满足必然性QoS约束的数据服务,是数据网格成功的关键.在副本放置模型的基础上,给出了QoS约束形式化的描述方法.并得出必然性QoS约束满足的形式化定义.针对必然性QoS约束的副本... 详细信息

如何提供严格有保障的数据服务质量,为每个数据访问请求提供满足必然性QoS约束的数据服务,是数据网格成功的关键.在副本放置模型的基础上,给出了QoS约束形式化的描述方法.并得出必然性QoS约束满足的形式化定义.针对必然性QoS约束的副本放置问题.在矩阵表示的基础上,利用矩阵操作给出一种有效的副本放置算法.分析和实验表明,该算法能够很好地解决各种规模条件下必然性QoS约束的副本放置问题,并具有稳定性和可扩展性的特点,在多种网络拓扑和访问模式下均能获得满足必然性QoS约束的副本策略.

关键词：数据网格必然性QoS 副本放置

Feature Matching via Topology-Aware Graph Interaction Model

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 113-130页

作者： Yifan Lu Jiayi Ma xiaoguang Mei Jun Huang xiao-ping Zhang the Electronic Information School Wuhan UniversityWuhan 430072China IEEE Tsinghua Berkeley Shenzhen Institute Shenzhen 518071China the Department of Electrical Computer and Biomedical EngineeringToronto Metropolitan UniversityToronto ON M5B 2K3Canada

Feature matching plays a key role in computer vision. However, due to the limitations of the descriptors, the putative matches are inevitably contaminated by massive *** paper attempts to tackle the outlier filtering problem from two aspects. First, a robust and efficient graph interaction model,is proposed, with the assumption that matches are correlated with each other rather than independently distributed. To this end, we construct a graph based on the local relationships of matches and formulate the outlier filtering task as a binary labeling energy minimization problem, where the pairwise term encodes the interaction between matches. We further show that this formulation can be solved globally by graph cut algorithm. Our new formulation always improves the performance of previous localitybased method without noticeable deterioration in processing time,adding a few milliseconds. Second, to construct a better graph structure, a robust and geometrically meaningful topology-aware relationship is developed to capture the topology relationship between matches. The two components in sum lead to topology interaction matching(TIM), an effective and efficient method for outlier filtering. Extensive experiments on several large and diverse datasets for multiple vision tasks including general feature matching, as well as relative pose estimation, homography and fundamental matrix estimation, loop-closure detection, and multi-modal image matching, demonstrate that our TIM is more competitive than current state-of-the-art methods, in terms of generality, efficiency, and effectiveness. The source code is publicly available at http://***/YifanLu2000/TIM.

关键词： Feature matching graph cut outlier filtering topology preserving

从礼器到日常用器——论两汉时期青铜容器的变化

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厦门大学学报（哲学社会科学版） 2006年第3期56卷 58-64页

作者：吴小平厦门大学历史系福建厦门361005

汉代是中国古代铜器发展史的重要时期,其间青铜容器完成了从礼器到日常用器、从周制转变为汉制的过程。主要体现在:器类方面,传统礼器逐渐消亡,日常用器种类增多;纹饰内容方面,从以神仙世界的灵异纹饰为主逐渐过渡到以人间的吉祥图案为... 详细信息

汉代是中国古代铜器发展史的重要时期,其间青铜容器完成了从礼器到日常用器、从周制转变为汉制的过程。主要体现在:器类方面,传统礼器逐渐消亡,日常用器种类增多;纹饰内容方面,从以神仙世界的灵异纹饰为主逐渐过渡到以人间的吉祥图案为主;铭文的内涵也由物勒工名转变为吉祥语言。从总体上看,西汉早期青铜容器还处在周制阶段,西汉晚期汉制才得到确立,西汉中期为过渡阶段。

关键词：礼器日常用器汉代青铜容器

单斜地形条件对激电对称四极测深拟断面图的影响

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地球物理学进展 2016年第5期31卷 2166-2171页

作者：吴小平湖南软件职业学院软件与信息工程学院湘潭411100

激电测深方法是一种典型的地球物理勘探方法.它被广泛应用于金属矿勘探及地下水勘探中.对称四极测深方法是野外激电测深的主要方法之一.理论上,激发极化方法很少受到地形的影响,主要是因为激发极化方法的基础是地下极化体受到激发电流... 详细信息

激电测深方法是一种典型的地球物理勘探方法.它被广泛应用于金属矿勘探及地下水勘探中.对称四极测深方法是野外激电测深的主要方法之一.理论上,激发极化方法很少受到地形的影响,主要是因为激发极化方法的基础是地下极化体受到激发电流的激发而产生的极化效应,从而产生二次极化电流,极化率与激发电流的大小没有直接的相关性.但在实际的应用中,由于地形条件的变化,可能导致测深装置的装置系数发生变化,人为的因素可能导致测深的拟断面图发生畸变,影响测深结果的解译.作者通过理论模型的推导方法,形象直观的演示了单斜地形条件下,对称四极激电测深拟断面图发生变形的过程.并通过新疆某地钨矿实例,说明了单斜地形条件下,对实测对称四极激电测深拟断面图进行修正的重要性.

关键词：单斜地形激电测深对称四极拟测深点位拟断面图