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Journal of Computer and Communications 2024年第1期12卷 1-10页

作者： Huichao Shang penglei li Xiangqian Peng School of Mechanical and Electrical Engineering Zhongyuan University of Technology Zhengzhou China School of Mechanical and Electrical Engineering Hunan University of Science and Technology Xiangtan China

To address the issue of deteriorated PCB image quality in the quality inspection process due to insufficient or uneven lighting, we proposed an image enhancement fusion algorithm based on different color spaces. Firstly, an improved MSRCR method was employed for brightness enhancement of the original image. Next, the color space of the original image was transformed from RGB to HSV, followed by processing the S-channel image using bilateral filtering and contrast stretching algorithms. The V-channel image was subjected to brightness enhancement using adaptive Gamma and CLAHE algorithms. Subsequently, the processed image was transformed back to the RGB color space from HSV. Finally, the images processed by the two algorithms were fused to create a new RGB image, and color restoration was performed on the fused image. Comparative experiments with other methods indicated that the contrast of the image was optimized, texture features were more abundantly preserved, brightness levels were significantly improved, and color distortion was prevented effectively, thus enhancing the quality of low-lit PCB images.

关键词： Low-lit PCB Images Spatial Transformation Image Enhancement Image Fusion HSV

不同吹扫模式下HI分解膜反应器多目标性能优化

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工程热物理学报 2024年第3期45卷 615-621页

作者：孔锐陈林根夏少军李鹏蕾戈延林海军工程大学动力工程学院武汉430033 武汉工程大学热科学与动力工程研究所武汉430205 武汉工程大学机电工程学院武汉430205 湖北省绿色化工装备工程技术研究中心武汉430205

建立了不同吹扫模式下碘化氢(HI)分解膜反应器有限时间热力学模型,将吹扫气流率、反应进口压力、渗透膜厚度、反应器长度作为决策变量,以HI转化率最大、H_(2)回收率最大、总熵产率最小为目标开展多目标优化。通过研究发现,在给定的决策... 详细信息

建立了不同吹扫模式下碘化氢(HI)分解膜反应器有限时间热力学模型,将吹扫气流率、反应进口压力、渗透膜厚度、反应器长度作为决策变量,以HI转化率最大、H_(2)回收率最大、总熵产率最小为目标开展多目标优化。通过研究发现,在给定的决策变量变化范围内HI转化率和H_(2)回收率最大两者具有一致性,但两者无法与总熵产率最小同时达到最优;相比顺流吹扫模式,逆流吹扫模式下Pareto前沿目标值均具有较高的HI转化率和H_(2)回收率。使用不同的决策方法选取最优解,顺流模式下的TOPSIS决策点和逆流模式下的liNMAP决策点具有较小的偏差因子可作为反应器参数设计最优解。

关键词：有限时间热力学 HI分解膜反应器 HI转化率 H_(2)回收率总熵产率多目标优化

推广种植业适度规模化经营中存在的问题及对策——以商丘睢阳区为例

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农业技术与装备 2024年第4期 56-58页

作者：李朋磊河南开封科技传媒学院河南开封475000

以睢阳区域农村地区为研究区域,以推广种植业适度规模化为研究课题,结合睢阳区域农业发展具体实际,探索了推广种植业适度规模化经营的对策,以期走出一条农业发展新道路,为商丘市农业发展提供新思路。

关键词：种植业适度规模化对策

Multi-objective optimization for membrane reactor for steam methane reforming heated by molten salt

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Science China(Technological Sciences) 2022年第6期65卷 1396-1414页

作者： CHEN linGen li penglei XIA ShaoJun KONG Rui GE Yanlin Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China College of Power Engineering Naval University of EngineeringWuhan 430033China Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan 430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China

A membrane reactor for steam methane reforming heated by molten salt(MS-SMRMR)is studied based on finite time thermodynamics for decreasing carbon emissions and improving hydrogen production rate(HPR).Effects of flow directions of sweep gas and molten salt on MS-SMRMR are *** of temperatures,HPR,and local entropy generation rates(EGRs)of MS-SMRMR are *** particle swarm optimization algorithm is utilized to obtain the minimum of specific EGR(SEGR),ratio of EGR to ***-objective optimization about HPR maximization and EGR minimization is performed by utilizing *** EGR caused by the mass transfer process is the largest among all irreversible processes in the *** membrane length should be slightly shorter than the reactor length when the flow direction of sweep gas is different from that of reaction *** flow directions of molten salt and sweep gas are opposite to that of reaction mixture,SEGR is the *** with SEGR calculated by utilizing initial parameters,SEGRs after primary,twice and triple optimizations reduce by 1.2%,5.5%and 5.7%,*** can be further decreased by adjusting other operating *** front provides many optimization results,and it contains SEGR *** Pareto front,an optimum decision point is obtained based on decision-making of TOPSIS,and its EGR and HPR,respectively,increase by 7.12%and13.24%,compared with those obtained by using initial *** results have certain theoretical guiding significance for optimization designs of MS-SMRMR.

关键词： finite time thermodynamics steam methane reforming membrane reactor specific entropy generation rate multiobjective optimization

Total entropy generation rate minimization configuration of a membrane reactor of methanol synthesis via carbon dioxide hydrogenation

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Science China(Technological Sciences) 2022年第3期65卷 657-678页

作者： li penglei CHEN linGen XIA ShaoJun KONG Rui GE Yanlin Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan 430205China College of Power Engineering Naval University of EngineeringWuhan 430033China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China

The total entropy generation rate,internal exergy loss and exergy efficiency of the membrane reactor of methanol synthesis via carbon dioxide hydrogenation are compared,and the results show that the total entropy generation rate minimization is equivalent to the internal exergy loss minimization and the exergy efficiency maximization under the fixed inlet ***,this paper optimizes the membrane reactor with total entropy generation rate minimization as an optimization objective under a fixed methanol production *** optimal temperatures curves of exterior walls for three optimal membrane reactors with different boundary conditions are obtained by using optimal control theory and nonlinear *** influences of other geometric and operating parameters on optimization results of optimal membrane reactors are *** results indicate that when inlet temperatures of the reaction mixture and mixture in the permeable tube are unfixed,the optimizing curve of exterior wall temperature makes the total entropy generation rate of membrane reactor reduce by 12.39%compared with the total entropy generation rate of a reference membrane reactor with a linear exterior wall *** the inlet molar flow rate of sweep gas and gas hourly space velocity and increasing inlet pressure of reaction mixture,the inlet pressure of mixture in the permeable tube and heat transfer coefficients are favorable for decreasing the total entropy generation rate in the membrane *** the porosity of catalyst bed and reactor length increases,the minimum total entropy generation rate decreases first and then *** the perspective of engineering application,this paper establishes two membrane reactors(membrane reactor heated by three-stage furnaces of the same length and membrane reactor heated by threestage furnaces of different lengths),*** minimum total entropy generation rates of the two reactors are reduced by11.67%and 11.79%compare

关键词： membrane reactor methanol synthesis via carbon dioxide hydrogenation multi-stage furnaces finite-time thermo-dynamics entropy generation rate minimization optimal configuration

大功率船用柴油机空气电机启动过程瞬态特性仿真

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造船技术 2024年第3期52卷 5-11页

作者：刘楠童大鹏孙青柯李鹏蕾海军士官学校机电系安徽蚌埠233012

为提升大功率船用柴油机启动性能,采用GT-power软件建立船用柴油机稳态模型,增加空气电机启动系统模块,构建柴油机启动过程瞬态模型。基于仿真结果,分析环境排气背压、润滑油温度和压缩空气系统参数等对柴油机启动性能的影响规律。仿真... 详细信息

为提升大功率船用柴油机启动性能,采用GT-power软件建立船用柴油机稳态模型,增加空气电机启动系统模块,构建柴油机启动过程瞬态模型。基于仿真结果,分析环境排气背压、润滑油温度和压缩空气系统参数等对柴油机启动性能的影响规律。仿真结果可为基于空气电机启动的大功率船用柴油机的系统参数设计和性能评估提供依据。

关键词：大功率船用柴油机空气电机启动过程瞬态特性 GT-power软件

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DSFA: cross-scene domain style and feature adaptation for landslide detection from high spatial resolution images

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International Journal of Digital Earth 2023年第1期16卷 2426-2447页

作者： penglei li Yi Wang Tongzhen Si Kashif Ullah Wei Han lizhe Wang School of Geophysics and Geomatics China University of GeosciencesWuhanPeople’s Republic of China School of Computer Science Wuhan UniversityWuhanPeople’s Republic of China School of Computer Science China University of GeosciencesWuhanPeople’s Republic of China

Rapid and accurate landslide inventory mapping is significant for emergency rescue and post-disaster ***,deep learning methods exhibit excellent performance in supervised landslide ***,due to differences between cross-scene images,the performance of existing methods is significantly degraded when directly applied to another scene,which limits the application of rapid landslide inventory *** this study,we propose a novel Domain Style and Feature Adaptation(DSFA)method for cross-scene landslide detection from high spatial resolution images,which can leverage labeled source domain images and unlabeled target domain images to mine robust landslide representations for different ***,we mitigate the large discrepancy between domains at the dataset level and feature *** the dataset level,we introduce a domain style adaptation strategy to shift landslide styles,which not only bridges the domain gap,but also increases the diversity of landslide *** the feature level,adversarial learning and domain distance minimization are integrated to narrow large feature distribution discrepancies for learning domain-invariant *** addition,to avoid information omission,we improve the U-Net3+*** experimental results demonstrate that DSFA has superior detection capability and outperforms other methods,showing its great application potential in unsupervised landslide domain detection.

关键词： Landslide detection deep learning remote sensing domain adaptation high spatial resolution

基于两性生命表评价取食柑橘木虱对六斑月瓢虫和龟纹瓢虫生长发育及种群的影响

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植物保护学报 2022年第2期49卷 629-636页

作者：周军辉徐腾李鹏雷黄建王竹红福建农林大学植物保护学院福州350002 新疆农业科学院植物保护研究所农业农村部西北荒漠作物有害生物综合治理重点实验室乌鲁木齐830091

为有效防控重要害虫柑橘木虱Diaphorina citri,在实验室条件下测定取食柑橘木虱后六斑月瓢虫Cheilomenes sexmaculata和龟纹瓢虫Propylea japonica各虫态的发育历期,利用构建的年龄-阶段两性生命表对取食柑橘木虱后六斑月瓢虫、龟纹瓢... 详细信息

为有效防控重要害虫柑橘木虱Diaphorina citri,在实验室条件下测定取食柑橘木虱后六斑月瓢虫Cheilomenes sexmaculata和龟纹瓢虫Propylea japonica各虫态的发育历期,利用构建的年龄-阶段两性生命表对取食柑橘木虱后六斑月瓢虫、龟纹瓢虫生长发育及其种群参数进行研究。结果显示,取食柑橘木虱后六斑月瓢虫羽化前的发育历期为14.80 d,显著长于取食柑橘木虱后龟纹瓢虫的14.41 d;取食柑橘木虱后六斑月瓢虫和龟纹瓢虫产卵期分别为15.88 d和10.23 d,前者显著长于后者;取食柑橘木虱后六斑月瓢虫净增殖率、内禀增长率和周限增长率分别为25.48、0.10 d^(-1)和1.10 d^(-1),取食柑橘木虱后龟纹瓢虫净增殖率、内禀增长率和周限增长率分别为14.13、0.06 d^(-1)和1.06 d^(-1),均低于取食柑橘木虱后六斑月瓢虫;取食柑橘木虱后六斑月瓢虫和龟纹瓢虫的平均世代周期分别为33.87 d和44.95 d,前者显著短于后者。表明取食柑橘木虱后六斑月瓢虫和龟纹瓢虫均能完成整个世代,且六斑月瓢虫种群增长优于龟纹瓢虫,可大规模繁殖六斑月瓢虫,可用于柑橘木虱的生物防治。

关键词：六斑月瓢虫龟纹瓢虫柑橘木虱年龄-阶段两性生命表

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双横臂悬架导向机构运动学分析及优化

汽车实用技术 2022年第5期47卷 54-57页

作者：李鹏雷周长城李颂孙家正山东理工大学交通与车辆工程学院山东淄博255049

论文针对双横臂悬架系统的特点,建立出悬架系统空间模型,进行运动学特性分析。利用ADAMS/Car软件建立起双横臂悬架系统仿真模型,分析车轮定位参数随车轮上下跳动的变化规律,以车轮定位参数为优化目标,导向机构的硬点坐标为设计变量进行... 详细信息

论文针对双横臂悬架系统的特点,建立出悬架系统空间模型,进行运动学特性分析。利用ADAMS/Car软件建立起双横臂悬架系统仿真模型,分析车轮定位参数随车轮上下跳动的变化规律,以车轮定位参数为优化目标,导向机构的硬点坐标为设计变量进行优化仿真。优化仿真结果表明,优化后的车轮定位参数相较优化之前缩小了变化范围,使该悬架的性能得到了提高。

关键词：悬架导向机构运动学特性分析车轮定位参数优化仿真

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椭圆式异形压缩螺旋弹簧力学特性计算分析

山东理工大学学报（自然科学版） 2022年第4期36卷 81-86页

作者：李颂周长城张云山李鹏雷山东理工大学交通与车辆工程学院山东淄博255049 山东汽车弹簧厂淄博有限公司山东淄博255410

椭圆式螺旋弹簧(即椭圆中径、椭圆丝径螺旋弹簧)是一种应用于特殊空间下的异形弹簧,目前尚无成熟可靠的椭圆式螺旋弹簧刚度及应力的计算方法。基于椭圆式螺旋弹簧的力学模型,利用卡氏定理建立其挠度及刚度的计算方法;基于弹性理论知识,... 详细信息

椭圆式螺旋弹簧(即椭圆中径、椭圆丝径螺旋弹簧)是一种应用于特殊空间下的异形弹簧,目前尚无成熟可靠的椭圆式螺旋弹簧刚度及应力的计算方法。基于椭圆式螺旋弹簧的力学模型,利用卡氏定理建立其挠度及刚度的计算方法;基于弹性理论知识,运用半逆解法建立了考虑受扭转应力及弯曲应力同时作用下,椭圆式螺旋弹簧的复合切应力计算方法。通过实例对弹簧进行ANSYS仿真验证,结果显示弹簧刚度的相对偏差在0.84%以内,最大复合切应力的最大偏差仅为2.19%,表明建立的椭圆式螺旋弹簧刚度及复合切应力计算方法是正确的。基于建立的弹簧任意位置的复合切应力计算方法,计算总结出弹簧簧丝截面、弹簧圈表面的复合切应力及弹簧簧丝截面弯曲切应力的分布变化规律,为此类弹簧的设计及应用提供了理论参考。

关键词：椭圆式螺旋弹簧刚度计算切应力计算半逆解法