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Infrared small target detection based on density peaks searching and weighted multi-feature local difference

Optoelectronics Letters 2024年

作者： JI Bin FAN Pengxiang WANG Mengli LIU Yang xu jiafeng School of Computer Science and Technology， Anhui University of Technology

In order to solve the problems of unknown target size， fuzzy edges， background interference and low contrast in infrared small target detection， this paper proposes an infrared small target detection method based on density peaks searching and weighted multi-feature local difference. Firstly， for the interference problem of high brightness clutter on the density peaks searching to obtain candidate targets， this paper adopts the improved high-boost filter for preprocessing， which effectively eliminates the background clutter and high brightness background interference in the infrared image， and improves the probability of the true target being captured in the density peaks searching process. Secondly， triple-layer windows are used to extract features from the area around the candidate target， which solves the problem of uncertain size of small targets. Additionally， by calculating the multiple feature local differences between triple-layer windows， the problem of blurred edges and low contrast for the targets are also resolved. In order to balance the contribution degree of different feature local differences to target detection， this paper introduces the intra-class distance to calculate the weight of each feature local differences， realizes the weighted fusion of multi-feature local differences， obtains the weighted multi-feature local difference of each candidate target， and extracts the real target from the candidate target through the interquartile range. Experiments on many different types of infrared image sequences consisting of publicly available datasets such as SIRST and IRSTD-1K show that the method proposed in this paper is applicable to a wide range of complex types with good robustness and detection performance.

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人工智能时代公安院校教师的身份重塑

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辽宁警察学院学报 2024年第3期26卷 85-91页

作者：徐佳峰中国人民警察大学移民管理学院广东广州510663

人工智能时代背景下,人工智能技术助力教师的开展教学,也将塑造全新的教师角色。智能技术的应用给公安教育的发展带来新机遇的同时也对教师提出了更高的要求。一方面,人工智能在公安工作广泛应用,公安教育数字化水平不断提升,人才培养... 详细信息

人工智能时代背景下,人工智能技术助力教师的开展教学,也将塑造全新的教师角色。智能技术的应用给公安教育的发展带来新机遇的同时也对教师提出了更高的要求。一方面,人工智能在公安工作广泛应用,公安教育数字化水平不断提升,人才培养多元化需求日益凸显。另一方面,人工智能冲击着传统的公安教育,教师角色面临知识传递权威性的挑战、课堂教学主导性的考验和坚守核心价值观的威胁等三重困境。面对人工智能的挑战,公安院校教师应当实现三个身份重塑:从传统知识权威到学习创新引领者,从课堂主导者到个性化学习促进者,从价值观守护者到灵魂塑造推动者。

关键词：人工智能公安教育角色重塑

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烧结料面裂缝产生原因及其与点火温度的关系

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烧结球团 2024年第2期49卷 25-30,98页

作者：郭会良薛玉卿玄振法徐佳锋李胜山东泰山钢铁集团有限公司山东济南271100

为保证烧结矿具有良好的冶金性能,同时提高料层透气性,本文通过分析料面裂缝的形状、长度和生长规律,研究裂缝产生的原因及其与点火温度之间的关系,采用光学显微镜查看裂缝处烧结矿的微观组织,并对裂缝处烧结矿进行力学分析。结果表明:... 详细信息

为保证烧结矿具有良好的冶金性能,同时提高料层透气性,本文通过分析料面裂缝的形状、长度和生长规律,研究裂缝产生的原因及其与点火温度之间的关系,采用光学显微镜查看裂缝处烧结矿的微观组织,并对裂缝处烧结矿进行力学分析。结果表明:在一定范围内,随着点火温度的升高,裂缝条数呈增加趋势,当点火温度大于1150℃时,裂缝条数反而呈减少趋势;随着点火温度的升高,裂缝产生的位置逐渐后移,即点火温度越高,裂缝的产生时间越晚;随着点火温度的升高,烧结矿中FeO质量分数呈下降趋势,但当温度超过1150℃后,烧结矿中FeO质量分数反而呈上升趋势;裂缝处烧结矿内有大量针状铁酸钙,存在适当的晶间裂缝和孔洞,且赤铁矿含量适中,质量优于内部的烧结矿;裂缝的产生能改善料层内部空气流通,增加料层透气性,进而改善烧结矿质量。理论计算结果表明,固熔物的斥力大于引力(F引

关键词：铁矿烧结料面裂缝点火温度化学成分 FeO 受力状态

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Experiments and insights of desalination by a freezing/thawing method at low subcooling

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Chinese Journal of Chemical Engineering 2020年第12期28卷 3011-3017页

作者： Jun Chen Jianjian Wu jiafeng xu Qing Yuan Bin Deng Changzhong Chen Zhi Li Hunan Provincial Key Laboratory of Xiangnan Rare-PreciousMetals Compounds and Applications College of Chemistry&Biology and Environmental EngineeringXiangnanUniversityChenzhou 423000China Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University of TechnologyDalian 116024China School of Chemistry and Chemical Engineering Liaocheng UniversityLiaocheng 252059China Shandong Provincial Key Laboratory of Molecular Engineering QiLu University of Technology(Shandong Academy of Sciences)Jinan 250353China

Desalination by freezing/thawing method was a very important method to obtain fresh water from *** this work,desalination by freezing/thawing method was conducted with initial sodium chloride of 3.5 wt% in consideration of stirring speed,freezing time and *** subcooling ranged from 1.2 K to 4 *** optimum conditions for desalination in this work were stirring speed of 200 r·min^−1,freezing time of 120 min,and subcooling of 3 *** results also showed that sodiumchloride cannot be effectively removed by once freezing/thawing *** maximumremoval efficiency of sodiumchloride was 64.3%.Two major reasons resulting in the impurity of obtained melted water by freezing/thawing method were *** first reason was the inevitable adhesion of salt solution to the surface of ice,which could be removed easily by distilled water *** second reason was that salt solution was heterogeneously wrapped in the accumulated ice,which was difficult to be removed by distilled water *** liquid flushing method was proposed to verify the conjecture,and the results were in accordance with the two reasons mentioned *** method,such as multiple flushing liquid method,was suggested to be used during the freezing/thawing process for effectively removing sodium chloride,and obtaining fresh water.

关键词： Desalination Ice Aqueous solution Separation Removal efficiency Mechanism

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Synergistic effect of V_(2)O_(5)and Bi_(2)O_(3) on the grain boundary structure of high-frequency NiCuZn ferrite ceramics

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Journal of Advanced Ceramics 2022年第6期11卷 912-921页

作者： Xiuyuan FAN Guohua BAI Zhenhua ZHANG Qiming CHEN Jiaying JINa jiafeng xua xuefeng ZHANG Mi YAN School of Materials Science and Engineering State Key Laboratory of Silicon MaterialsKey Laboratory of Novel Materials for Information Technology of Zhejiang ProvinceZhejiang UniversityHangzhou 310027China Institute of Advanced Magnetic Materials College of Materials&Environmental EngineeringHangzhou Dianzi UniversityHangzhou 310012China

High-frequency soft magnetic ferrite ceramics are desired in miniaturized and efficient power electronics but remain extremely challenging to deploy on account of the power loss(Pcv)at megahertz ***,we prepared NiCuZn ferrite with superior high-frequency properties by V_(2)O_(5)and Bi_(2)O_(3)synergistic doping,which proves to be a potent pathway to reduce Pcv of the ferrite at megahertz *** sample doped with 800 ppm V_(2)O_(5)and 800 ppm Bi_(2)O_(3)yielded the most optimized magnetic properties with a Pcv of 113 kW/m^(3)(10 MHz,5 mT,25℃),an initial permeability(μi)of 89,and a saturation induction(Bs)of 340 mT,which is at the forefront of the reported *** outstanding properties are closely related to the notable grain boundary structure,which features a new type of nano-Bi_(2)Fe_(4)O_(9)phase around ferrite grains and a Ca/Si/V/O amorphous *** results indicate great strides in correlating the grain boundary structure with multiple-ion doping and set the scene for the developing high-frequency soft magnet ferrites.

关键词： NiCuZn ferrite megahertz application grain boundary Bi_(2)Fe_(4)O_(9) ion doping

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Bat Algorithm Optimizer for Drilling Trajectory Designing under Wellbore Stability Constraints

Bat Algorithm Optimizer for Drilling Trajectory Designing un...

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第37届中国控制会议

作者： jiafeng xu Xin Chen School of Automation China University of Geosciences Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems China University of Geosciences

In the process of deep geological resources exploration, there are often some complex stratigraphic situations. A threedimension drilling trajectory is designed by using the geological environment data. The trajectory should be sure that the target position is reachable. And it can avoid the area prone to be in an accident. In order to solve this problem, this paper discusses a three-dimensional wellbore trajectory design optimization model suitable for shale gas horizontal mining. Considering the wellbore stability and dogleg severity as constraints, the minimum drilling length is taken as the objective function. Depending on the Mohr-Coulomb criterion, the range of azimuth angle and inclination angle of safety trajectory can be determined. It can be seen as a constraint on the wellbore derrick segment. As for the optimization algorithm, bat algorithm（BA） optimizer combined with a penalty function method is applied to this optimization model. Finally, the case study shows that the BA performs well in the wellbore optimization design. It obtains the trade-off result between the safe and efficient drilling demands. And, it provides a basic model idea for the real-time trajectory optimization while drilling.

关键词： Drilling Trajectory Designing Wellbore Stability Bat Algorithm

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Refinement of α′Martensite by Oxygen in Selective Laser Melted Ti-6Al-4V

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 777-792页

作者： Hasfi FNurly Jinhu Zhang Dechun Ren Yusheng Cai Haibin Ji Dongsheng xu Zhicheng Dong Hao Wang Qingmiao Hu jiafeng Lei Rui Yang School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials and Chemistry/Interdisciplinary Centre for Additive Manufacturing University of Shanghai for Science and TechnologyShanghai 200093China Centre for Adaptive System Engineering ShanghaiTech UniversityShanghai 201210China

Oxygen is crucial in influencing the microstructure evolution of selective laser melted(SLMed)Ti–6Al–4V,significantly impacting its applicability in various ***,this study investigates the influnce of oxygen on microstructure evolution,particularlyα′martensite transformation and refinement *** alloys,Ti–6Al–4V–xO(x=0.11,0.16,0.21,and 0.25 wt%),were fabricated by the SLM *** martensite start temperature(M_(s))of Ti–6Al–4V,as evaluated by computation,is 656.8°C,and oxygen was found to increase the M_(s) by about 10°C per 0.1 wt%.The SLMed alloy samples exhibit[001]_(β)growth texture along the build *** analysis of martensite morphology suggests internal twinning on{1011}planes as the lattice invariant strain,which becomes more predominant with increasing oxygen *** of α′martensite plates by oxygen is due to increased lattice distortion,reduced prior β grain size,and oxygen segregation toβgrain *** findings contribute to improving the understanding of the effect of oxygen on the transformation mechanism ofα′martensite during SLM of Ti–6Al–4V.

关键词： Selective laser melting α′Martensite Martensite start temperature Oxygen Ti-6Al-4V

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Inverse Kinematic Control Method of Redundant Manipulators with Joint Limits Constraints

Inverse Kinematic Control Method of Redundant Manipulators w...

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第37届中国控制会议

作者： Ting Fei Xin Chen jiafeng xu School of Automation China University of Geosciences Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems

For the control problem of redundant manipulators with joint limits constraints, a novel method combining the simplified clamping weighted least-norm method and the typical gradient projection method is proposed in this paper. The method solves the problem that the manipulability of the redundant manipulator is poor caused by the clamping weighted least-norm method and makes the joint velocity change more smoothly. The proposed novel method is implemented on a kinematic redundant manipulator with four degree-of-freedom（DOF） which belongs to the dulcimer music-playing robot. The numerical simulation results show that the joint positions are well-bounded within the joint limits and the manipulator has a good performance for tracking a given trajectory.

关键词： Redundant manipulators Joint limits Inverse kinematic control

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连杆衬套强力旋压成形的多目标优化与决策

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锻压技术 2022年第2期47卷 119-125页

作者：张冰徐嘉锋许昌职业技术学院信息工程学院河南许昌461000

为了减小连杆衬套强力旋压成形的圆柱度误差和壁厚偏差,提出了基于加权相对距离的最优解决策策略。介绍了连杆衬套的强力旋压成形工艺,以减小圆柱度误差和壁厚偏差为目标建立了多目标优化模型。使用RBF神经网络和有限元仿真软件拟合了... 详细信息

为了减小连杆衬套强力旋压成形的圆柱度误差和壁厚偏差,提出了基于加权相对距离的最优解决策策略。介绍了连杆衬套的强力旋压成形工艺,以减小圆柱度误差和壁厚偏差为目标建立了多目标优化模型。使用RBF神经网络和有限元仿真软件拟合了工艺参数与目标参数之间的函数关系,经验证RBF神经网络的拟合精度较高。使用非支配排序遗传算法对多目标优化模型进行求解,得到了Pareto前沿解集。建立了理想解和不理想解的概念,提出了基于加权相对距离的最优解决策方法。经生产验证,优化后的圆柱度误差均值比厂家生产的圆柱度误差均值减小了23.16%,壁厚偏差均值减小了23.94%,且两个质量参数的标准差也有所下降。实验结果说明:优化后的连杆衬套圆柱度误差和壁厚偏差均有所减小,且生产稳定性有所提高。

关键词：连杆衬套强力旋压圆柱度误差壁厚偏差 Pareto前沿解加权相对距离非支配排序遗传算法

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带有时间戳的着色逻辑Petri网

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计算机科学与探索 2024年第7期18卷 1776-1791页

作者：王嘉丰徐贤华东理工大学信息科学与工程学院上海200237

针对扩展着色逻辑Petri网存在的表达能力弱以及适用范围窄的问题,提出了一个新的Petri网模型,即带有时间戳的着色逻辑Petri网。首先,将颜色进行实例化以及将变量用于构建有向边上的表达式使得模型能够传递复杂的数据流。其次,引入全局... 详细信息

针对扩展着色逻辑Petri网存在的表达能力弱以及适用范围窄的问题,提出了一个新的Petri网模型,即带有时间戳的着色逻辑Petri网。首先,将颜色进行实例化以及将变量用于构建有向边上的表达式使得模型能够传递复杂的数据流。其次,引入全局时间以及令牌的时间戳等概念为变迁使能规则增加时间上的约束,使得模型能够用于模拟实时系统。再次,定义库所约束函数并为变迁使能规则增加输出库所上的约束,使得模型能够适用于存储资源有限的场景。接着,提出基于逻辑变迁输入输出矩阵的匹配法,降低逻辑输入变迁的使能判定计算开销并简化逻辑输出变迁的使能判定计算过程。然后,重新定义适用于三类变迁的使能判定条件以及适用于三类库所的标记更新方法,解决原有模型语义在新模型中不适用的问题。最后,通过实例说明新的Petri网模型具有更强的表达能力和适用范围,它能够适用于传递复杂数据流、存储资源有限、实时的且包含批处理选择结构的系统。

关键词： Petri网时间戳着色令牌逻辑变迁

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