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A Novel Multi-Stream Fusion Network for Underwater Image Enhancement

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China Communications 2024年第2期21卷 166-182页

作者： Guijin Tang lian Duan Haitao Zhao feng liu Jiangsu Key Laboratory of Image Processing and Image Communication Nanjing University of Posts and TelecommunicationsNanjing 210003China Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China

Due to the selective absorption of light and the existence of a large number of floating media in sea water, underwater images often suffer from color casts and detail blurs. It is therefore necessary to perform color correction and detail restoration. However,the existing enhancement algorithms cannot achieve the desired results. In order to solve the above problems, this paper proposes a multi-stream feature fusion network. First, an underwater image is preprocessed to obtain potential information from the illumination stream, color stream and structure stream by histogram equalization with contrast limitation, gamma correction and white balance, respectively. Next, these three streams and the original raw stream are sent to the residual blocks to extract the features. The features will be subsequently fused. It can enhance feature representation in underwater images. In the meantime, a composite loss function including three terms is used to ensure the quality of the enhanced image from the three aspects of color balance, structure preservation and image smoothness. Therefore, the enhanced image is more in line with human visual ***, the effectiveness of the proposed method is verified by comparison experiments with many stateof-the-art underwater image enhancement algorithms. Experimental results show that the proposed method provides superior results over them in terms of MSE,PSNR, SSIM, UIQM and UCIQE, and the enhanced images are more similar to their ground truth images.

关键词： image enhancement multi-stream fusion underwater image

基于化学成分对不锈钢板材拉伸试验过程的有限元模拟研究

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中国检验检测 2024年第1期32卷 12-15页

作者：王传玉刘凤莲韩方东丁卫平滨州市检验检测中心滨州256606 滨州市特种设备检验研究院滨州256606

采用材料性能模拟软件JMatPro 10.0和有限元分析软件ABAQUS 2021相结合,对不锈钢板材S30408、S31608拉伸试验过程性能数值进行模拟计算分析,将不同牌号不锈钢板材的元素含量输入JMatPro10.0得到出材料的泊松比、密度、弹性模量、屈服强... 详细信息

采用材料性能模拟软件JMatPro 10.0和有限元分析软件ABAQUS 2021相结合,对不锈钢板材S30408、S31608拉伸试验过程性能数值进行模拟计算分析,将不同牌号不锈钢板材的元素含量输入JMatPro10.0得到出材料的泊松比、密度、弹性模量、屈服强度、应力-应变关系等参数,输入ABAQUS 2021软件构建材料属性本构;通过建立几何模型、网格模型、构建材料属性及后续数据处理等得到拉伸时某一过程的Mises应力云图、应力-应变曲线,并结合实际拉伸试验进行了验证。经结果验证,模拟计算得出的应力-应变曲线与实际拉伸试验在弹性阶段、屈服阶段变化趋势以及抗拉强度数值大小方面基本吻合。该方法可用于分析不锈钢板材在塑性变形时的金属内部质点流动情况,为数值模拟计算分析应用于与钢铁行业新材料拉伸性能研究提供理论依据。

关键词：不锈钢板材元素含量材料参数拉伸试验过程有限元分析

霍乱弧菌O1群与O139群产毒株多酶恒温快速扩增检测方法的建立

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现代预防医学 2024年第4期51卷 705-712页

作者：丁卫平张士财伊廷存刘凤莲刘晓鹏赵志强霍胜楠钟棋宝蔡磊滨州市检验检测中心山东省食品药品检验研究院浙江工商大学食品与生物工程学院

目的建立一种霍乱弧菌O1群与O139群产毒株快速准确的检测方法。方法基于多酶恒温快速扩增技术，根据霍乱弧菌溶血素编码基因、霍乱毒素编码基因、O1群与O139群O抗原编码基因设计引物与探针，初步建立检测方法。以不同血清型霍乱弧菌... 详细信息

目的建立一种霍乱弧菌O1群与O139群产毒株快速准确的检测方法。方法基于多酶恒温快速扩增技术，根据霍乱弧菌溶血素编码基因、霍乱毒素编码基因、O1群与O139群O抗原编码基因设计引物与探针，初步建立检测方法。以不同血清型霍乱弧菌及其它细菌DNA为模板，验证检测方法的特异性与灵敏度。结果配制反应体系时，按试剂盒说明书推荐加入量0.6μL加入探针时可成功扩增溶血素编码基因、霍乱毒素编码基因及O1群与O139群O抗原编码基因4个目的基因，针对上述4个基因分别优化探针加入量为1.0μL、1.0μL、1.0μL、0.8μL时扩增效率更高。对优化探针加入量的检测方法进行方法特异性验证时，各引物探针组合不与非目标菌DNA产生交叉反应。进行检测方法的灵敏度分析时，不同目的基因的基因组检测灵敏度为70 fg或290 fg。上述实验结果证明检测方法的灵敏度及特异性满足设计要求。结论建立了一种霍乱弧菌O1群与O139群产毒株检测的新方法，该方法特异性强、灵敏度高、检测时间短，可适用于霍乱弧菌的常规检测及快检，对霍乱的预防具有一定的积极作用。

关键词：多酶恒温快速扩增霍乱弧菌产毒株检测

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弹塑性颗粒物质准静态变形的细观力学行为

岩土工程学报 2007年第4期29卷 524-530页

作者：刘连峰中国地质大学(北京)工程技术学院力学教研室北京100083

本文介绍了对由弹塑性圆球组成的粒度多分散系统进行的轴向准静态加载和卸载的数值模拟成果。首先介绍了基于理论接触力学导出的颗粒弹塑性接触模型,进而阐明了基于颗粒离散元法对颗粒物质准静态变形模拟的基本方法。研究发现:弹塑性球... 详细信息

本文介绍了对由弹塑性圆球组成的粒度多分散系统进行的轴向准静态加载和卸载的数值模拟成果。首先介绍了基于理论接触力学导出的颗粒弹塑性接触模型,进而阐明了基于颗粒离散元法对颗粒物质准静态变形模拟的基本方法。研究发现:弹塑性球颗粒系统在加载时其轴向刚度对颗粒间产生的塑性变形量及颗粒间的摩擦均很敏感。然而,颗粒间的摩擦对轴向加载时系统产生的水平应力没有很强的影响。数值模拟还提供了颗粒量级上的微力学内部变量的信息。这里引入并介绍了结构异性张量、滑动接触比率以及平均配位数。通过对这些参数的研究表明:在卸载的全过程中,颗粒间相对滑移出现,相互作用的颗粒数减少,系统内部结构产生不可恢复变形。因此,尽管在卸载应力应变曲线的初始段约为线性,但这并不意味着颗粒系统的响应如传统连续力学中假定的那样为弹性。

关键词：离散单元法颗粒物质细观力学理想弹塑性加载和卸载

Emerging materials and transistors for integrated circuits

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National Science Review 2024年第3期11卷 7-8页

作者： Ming liu lian-Mao Peng Lab of Nanofabrication and Novel Device Integration Institute of Microelectronics Chinese Academy of Sciences Key Laboratory for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics School of Electronics Peking University

The device technology for integrated circuits(ICs) has received a great deal of attention in the past decade since the mainstream silicon-based complementary metal-oxide-semiconductor(CMOS) field-effect transistor(FET) for modern ICs had been encountering development bottlenecks due to the combination of power constraints, physics, cost and fabrication processes.

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A vibration isolator with a controllable quasi-zero stiffness region based on nonlinear force design

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1279-1294页

作者： Xinyu lian Bing liu Huaxia DENG Xinglong GONG CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China

To achieve stability optimization in low-frequency vibration control for precision instruments,this paper presents a quasi-zero stiffness(QZS)vibration isolator with adjustable nonlinear ***,the stress-magnetism coupling model is established through meticulous theoretical *** controllable QZS interval is constructed via parameter design and magnetic control,effectively segregating the high static stiffness bearing section from the QZS vibration isolation ***,a displacement control scheme utilizing a magnetic force is proposed to regulate entry into the QZS working range for the vibration isolation *** results demonstrate that the operation within this QZS region reduces the peak-to-peak acceleration signal by approximately 66.7%compared with the operation outside this region,thereby significantly improving the low frequency performance of the QZS vibration isolator.

关键词： low frequency nonlinear vibration isolator quasi-zero stiffness(QzS)

Recent advances in fabrication and functions of neuromorphic system based on organic field effect transistor

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International Journal of Extreme Manufacturing 2024年第2期6卷 273-295页

作者： Yaqian liu Minrui lian Wei Chen Huipeng Chen School of Physics and Electronic Engineering Zhengzhou University of Light IndustryHenan 450002People’s Republic of China Institute of Optoelectronic Display National&Local United Engineering Lab of Flat Panel Display TechnologyFuzhou UniversityFuzhou 350002People’s Republic of China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207People’s Republic of China Department of Chemistry National University of Singapore3 Science Drive 3Singapore 117543Singapore Department of Physics National University of Singapore3 Science Drive 3Singapore 117543Singapore

The development of various artificial electronics and machines would explosively increase the amount of information and data,which need to be processed via in-situ *** synapse devices can store and process signals in a parallel way,thus improving fault tolerance and decreasing the power consumption of artificial *** organic field effect transistor(OFET)is a promising component for bioinspired neuromorphic systems because it is suitable for large-scale integrated circuits and flexible *** this review,the organic semiconductor materials,structures and fabrication,and different artificial sensory perception systems functions based on neuromorphic OFET devices are ***,a summary and challenges of neuromorphic OFET devices are *** review presents a detailed introduction to the recent progress of neuromorphic OFET devices from semiconductor materials to perception systems,which would serve as a reference for the development of neuromorphic systems in future bioinspired electronics.

关键词： organic field effect transistor neuromorphic systems synaptic transistor sensory perception systems device fabrication

Comparison of thermal shock resistance capabilities of the rotary swaged pure tungsten,potassium-doped tungsten,and W-La2O3 alloys

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Tungsten 2024年第4期6卷 759-766页

作者： Tao Yang Hao Wang Fan feng Xiang liu Xue-Yu Gong You-Yun lian Jian-Bao Wang School of Nuclear Science and Technology University of South China Southwestern Institute of Physics

Tungsten-based materials are one of the most important candidates for the plasma facing materials（PFMs） of future fusion reactors,and it is necessary to study the properties of tungsten-based materials under the service conditions of fusion devices to ensure the long-term steady-state operation of future fusion *** this paper,different tungsten-based materials made by the same rotary swaging process are selected to simulate the transient thermal loads on the PFMs of a fusion reactor using an electron beam,and thermal load experiments are carried out by changing the power density of a loading pulse and the pulse *** is found that different tungsten-based materials made by the same process have large differences in thermal shock resistance,and the doped tungsten materials（W-K and W-La2O3） are significantly better than the pure tungsten materials with the increase in thermal shock power density and the number of cycles,especially the W-K materials,which have excellent performance.

关键词： Electron beam Rotary swaging Thermal shock Tungsten materials

A condition-based maintenance policy for reconfigurable multi-device systems

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Advances in Manufacturing 2024年第2期12卷 252-269页

作者： Shu-lian Xie feng Xue Wei-Min Zhang Jia-Wei Zhu School of Mechanical Engineering Tongji UniversityShanghai201804People’s Republic of China

The exploration of component states for optimizing maintenance schedules in complex systems has garnered significant interest from ***,current literature usually overlooks the critical aspects of system flexibility and *** implementation of system reconfiguration can effectively mitigate system downtime and enhance production *** study proposes a dynamic condition-based maintenance policy considering reconfiguration for reconfigurable systems.A double-layer decision rule was constructed for the devices and *** achieve the best overall maintenance effect of the system,the remaining useful life probability distribution and recommended maintenance time of each device were used to optimize the concurrent maintenance time window of the devices and determine whether to reconfigure them.A comprehensive maintenance efficiency index was introduced that simultaneously considered the maintenance cost rate,reliability,and availability of the system to characterize the overall maintenance *** reconfiguration cost was included in the maintenance *** proposed policy was tested through numerical experiments and compared with different-level *** results show that the proposed policy can significantly reduce the downtime and maintenance costs and improve the overall system reliability and availability.

关键词： Condition-based maintenance(CBM) Reconfigurable system Remaining useful life Maintenance cost System reliability