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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1089-1097页

作者： jianjun xu Hanlin Ding Xin Lin Feng Liu Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

The microstructure characteristics and strengthening mechanism of Inconel738LC(IN-738LC) alloy prepared by using induction-assisted directed energy deposition(IDED) were elucidated through the investigation of samples subjected to IDED under 1050℃ preheating with and without hot isostatic pressing(HIP,1190℃,105 MPa,and 3 h).Results show that the as-deposited sample mainly consisted of epitaxial columnar crystals and inhomogeneously distributed γ’ phases in interdendritic and dendritic core *** HIP,grain morphology changed negligibly,whereas the size of the γ’ phase became increasingly *** further heat treatment(HT,1070℃,2 h + 845℃,24 h),the γ’ phase in the as-deposited and HIPed samples presented a bimodal size distribution,whereas that in the as-deposited sample showed a size that remained *** comparison of tensile properties revealed that the tensile strength and uniform elongation of the HIP + HTed sample increased by 5% and 46%,respectively,due to the synergistic deformation of bimodal γ’phases,especially large cubic γ’ ***,the relationship between phase transformations and plastic deformations in the IDEDed sample was discussed on the basis of generalized stability theory in terms of the trade-off between thermodynamics and kinetics.

关键词： directed energy deposition Ni-based superalloys high-temperature preheating hot isostatic pressing microstructure tensile properties

Changes of tropical cyclone size in three oceanic basins of the northern hemisphere from 2001 to 2021

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Frontiers of Earth Science 2024年第2期18卷 312-323页

作者： Banglin ZHANG Jeremy Cheuk-Hin LEUNG Shengyuan LIU jianjun xu Guangzhou Institute of Tropical and Marine Meteorology/Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction CMAGuangzhou 510640China College of Atmospheric Science Lanzhou UniversityLanzhou 730020China College of Ocean and Meteorology Guangdong Ocean UniversityZhanjiang 524088China CMA-GDOU Joint Laboratory for Marine Meteorology&South China Sea Institute of Marine Meteorology Guangdong Ocean UniversityZhanjiang 524088China

In this study the changes of tropical cyclone(TC)size from 2001 to 2021 are analyzed based on linear and quadratic curve fittings of the National Hurricane Center(NHC)/Joint Typhoon Warning Center(JTWC)best track data,based on the radius of maximum wind(RMW)and the average radius of 34-kt wind(AR34),in three oceanic basins of the North Atlantic(NATL),the Western North Pacific(WPAC)and the Eastern North Pacific(EPAC).The computations are done separately for two categories of tropical cyclones:tropical storms(TS)and hurricanes(HT).Size changes of landfalling and non-landfalling TCs are also *** show that there is a great inter-basin variability among the changes in TC *** conclusions include:1)overall,the inner cores of TSs have become larger in all three basins,with the increasing tendencies being significant in the NATL and WAPC,while those of HTs mostly get smaller or remain similar;2)meanwhile,comparatively large inter-basin differences are observed for the TC outer core sizes,and the sizes of landfalling TCs;3)particularly,a significant decrease in landfalling HT outer core size is observed over the EPAC;4)in contrast,significant increases in landfalling TS inner core size are found over the NATL and *** presented analysis results could benefit future research about TC forecasts,storm surge studies,and the cyclone climate and its changes.

关键词： tropical cyclone storm size frequency intensity duration

Combinatorial Optimization of Physics Parameterization Schemes for Typhoon Simulation Based on a Simple Genetic Algorithm(SGA)

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Journal of Meteorological Research 2024年第1期38卷 10-26页

作者： Zebin LU jianjun xu Zhiqiang CHEN Jinyi YANG Jeremy Cheuk-Hin LEUNG Daosheng xu Banglin ZHANG China Meteorological Administration–Guangdong Ocean University Joint Laboratory for Marine Meteorology South China Sea Institute of Marine MeteorologyGuangdong Ocean UniversityZhanjiang 524088 College of Ocean and Meteorology Guangdong Ocean UniversityZhanjiang 524088 Guangzhou Institute of Tropical and Marine Meteorology/Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction China Meteorological AdministrationGuangzhou 510640 Shenzhen Institute of Guangdong Ocean University Shenzhen 518120 College of Atmospheric Science Lanzhou UniversityLanzhou 730000

Each physical process in a numerical weather prediction(NWP)system may have many different parameterization *** studies have shown that the performance of different physical parameterization schemes varies with the weather situation to be ***,it is necessary to select a suitable combination of physical parameterization schemes according to the variation of weather ***,it is rather difficult to identify an optimal combination among millions of possible parameterization scheme *** study applied a simple genetic algorithm(SGA)to optimizing the combination of parameterization schemes in NWP models for typhoon *** feasibility of SGA was verified with the simulation of Typhoon Mujigae(2015)by using the Weather Research and Forecasting(WRF)model and Typhoon Higos(2020)by using the Coupled Ocean–Atmosphere–Wave–Sediment Transport(COAWST)modeling *** results show that SGA can efficiently obtain the optimal combination of *** Typhoon Mujigae(2015),the optimal combination can be found from the 1,304,576 possible combinations by running only 488 *** results can be obtained for Typhoon Higos(2020).Compared to the default combination proposed by the COAWST model system,the optimal combination scheme significantly improves the simulation of typhoon track and *** study provides a feasible way to search for the optimal combinations of physical parameterization schemes in WRF and COAWST for more accurate typhoon *** can help provide references for future development of NWP models,and for analyzing the coordination and adaptability of different physical process parameterization schemes under specific weather backgrounds.

关键词： simple genetic algorithm(SGA) combinatorial optimization typhoon forecast numerical weather prediction(NWP)

Diagnostic Study of an Extreme Explosive Cyclone over the Kuroshio/Kuroshio Extension Region

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Journal of Ocean University of China 2024年第3期23卷 605-617页

作者： ZHANG Shuqin LIAO Qinghua LIU Chunlei GAO Xiaoyu LONG Jingchao LI Pengyuan xu jianjun College of Ocean and Meteorology Guangdong Ocean UniversityZhanjiang 524088China South China Sea Institute of Marine Meteorology Guangdong Ocean UniversityZhanjiang 524088China CMA-GDOU Joint Laboratory for Marine Meteorology Guangdong Ocean UniversityZhanjiang 524088China Key Laboratory of Climate Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong ProvinceGuangdong Ocean UniversityZhanjiang 524088China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Department of Marine Meteorology Ocean-Atmosphere Interaction and Climate LaboratoryKey Laboratory of Physical OceanographyOcean University of ChinaQingdao 266100China

Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension *** most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-April)was studied to reveal the variations of the key factors at different explosive-developing *** EC had weak low-level baroclinicity,mid-level cyclonic-vorticity advection,and strong low-level water vapor convergence at the initial explosive-developing *** low-level baroclinicity and mid-level cyclonic-vorticity advection increased substantially during the maximum-deepening-rate *** diagnostic analyses using the Zwack-Okossi equation showed that diabatic heating was the main contributor to the initial rapid intensification of this *** cyclonic-vorticity advection and warm-air advection enhanced rapidly in the middle and upper troposphere and contributed to the maximum rapid intensification,whereas the diabatic heating weakened slightly in the mid-low *** relative contribution of the diabatic heating decreased from the initial explosive-developing stage to the maximum-deepening-rate stage due to the enhancement of other factors(the cyclonic-vorticity advection and warm-air advection).Furthermore,the physical factors contributing to this EC varied with the explosive-developing *** non-key factors at the initial explosive-developing stage need attention to forecast the rapid intensification.

关键词： explosive cyclone diabatic heating cyclonic-vorticity advection rapid intensification the Kuroshio/Kuroshio Extension region

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多机协同的类脑同步定位建图方法

机器人 2024年第4期46卷 465-475页

作者：赵杭飘徐剑君李涛唐凤珍中国科学院沈阳自动化研究所机器人学国家重点研究室辽宁沈阳110016 中国科学院大学北京100049 沈阳工业大学辽宁沈阳110870

低计算量和存储量的优势使得类脑导航模型RatSLAM适用于大型环境的地图构建。为了进一步提高其建图效率,本文提出了一种多机器人协同RatSLAM系统。首先,设计使用了集中式的通信系统用于机器人间信息的交互。其次,提出了一种环境重叠区... 详细信息

低计算量和存储量的优势使得类脑导航模型RatSLAM适用于大型环境的地图构建。为了进一步提高其建图效率,本文提出了一种多机器人协同RatSLAM系统。首先,设计使用了集中式的通信系统用于机器人间信息的交互。其次,提出了一种环境重叠区域检测方法以实现机器人之间的数据关联,从而进行经验节点间相对位姿计算。最后,提出一种改进型图松弛算法,利用机器人之间的位姿关系进行多机器人地图融合,完成全局统一的经验认知地图的实时在线构建。在公开数据集上以及真实物理实验环境中验证了所提方法的有效性。实验结果表明,相比单机器人,多机器人在保持较高地图精度与较少存储量的同时,平均建图效率提升45%。进一步与当前其他地图融合方法进行了比较,本文方法取得了更好的建图结果,验证了所提方法的有效性和准确性。

关键词：同步定位与建图(SLAM) 类脑导航 RatSLAM 多机器人地图融合

基于虚拟目标制导的自适应Q学习路径规划算法

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计算机集成制造系统 2024年第2期30卷 553-568页

作者：李子怡胡祥涛张勇乐许建军安徽大学电气工程与自动化学院安徽合肥230601

针对经典强化学习算法用于未知环境下机器人路径规划问题时,存在探索效率低、收敛速度慢、易陷入地形陷阱,以及学习过程缺少中间态导致探索盲目性等问题,设计了双重记忆机制、虚拟目标引导方法、自适应贪婪因子,提出基于虚拟目标引导的... 详细信息

针对经典强化学习算法用于未知环境下机器人路径规划问题时,存在探索效率低、收敛速度慢、易陷入地形陷阱,以及学习过程缺少中间态导致探索盲目性等问题,设计了双重记忆机制、虚拟目标引导方法、自适应贪婪因子,提出基于虚拟目标引导的自适应Q学习算法。设计了4种环境地图,同其他改进算法进行了对比仿真实验,并通过四驱麦克纳姆轮机器人虚拟仿真实验验证算法性能。实验结果表明,新算法显著减少了迭代次数,提高了强化学习收敛速度,且对复杂环境具有较好的鲁棒性,能够有效避免地形陷阱,提高移动机器人导航系统性能,为移动机器人自主路径规划提供了参考。

关键词： Q学习路径规划强化学习移动机器人

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詹姆士论个人气质对哲学倾向的影响

西部学刊 2024年第3期 58-61页

作者：徐健军黑龙江大学哈尔滨150000

有观点认为哲学家是在严肃对待客观前提与条件的基础上建立起的哲学体系,实用主义的奠基人威廉·詹姆士却提出了不一样的看法,他认为个人气质的引导在其中也扮演了重要的角色,哲学家个人的气质或冷酷或温和、或残忍或人道,将在很大程度... 详细信息

有观点认为哲学家是在严肃对待客观前提与条件的基础上建立起的哲学体系,实用主义的奠基人威廉·詹姆士却提出了不一样的看法,他认为个人气质的引导在其中也扮演了重要的角色,哲学家个人的气质或冷酷或温和、或残忍或人道,将在很大程度上影响其哲学道路的选择。詹姆士的这种理论被称作“哲学气质说”,该学说根据哲学气质的不同把哲学分为“柔和的”和“刚毅的”两大类,每一大类下又包括众多的小类。对于理性主义和经验主义这两种典型的哲学倾向,詹姆士分析了两者的特点,同时也论述了各自存在的弊端。“哲学气质说”把研究的核心放在了活生生的人身上,它关注个人的天性、喜好、习惯等对哲学倾向的影响,提供了一种新的视角来看待哲学及其冲突与发展,为深入地理解詹姆士的实用主义思想提供了素材。

关键词：詹姆士哲学气质说实用主义个人气质

某220m钢筋混凝土烟囱可靠性鉴定与加固方案研究

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工程技术研究 2024年第1期9卷 106-109页

作者：徐建军中国京冶工程技术有限公司北京100088

某现浇钢筋混凝土单筒式锥形烟囱已出现明显的劣化现象,混凝土筒壁表面多处出现竖向裂缝或环向裂缝,钢筋外露并出现锈蚀现象。基于此,文章全面检测了该烟囱主体结构的现状,对现状结构的安全性进行验算复核,并根据验算评估结果提出相应... 详细信息

某现浇钢筋混凝土单筒式锥形烟囱已出现明显的劣化现象,混凝土筒壁表面多处出现竖向裂缝或环向裂缝,钢筋外露并出现锈蚀现象。基于此,文章全面检测了该烟囱主体结构的现状,对现状结构的安全性进行验算复核,并根据验算评估结果提出相应的加固处理方案,对同类工程具有重要的参考价值。

关键词：钢筋混凝土烟囱结构检测可靠性鉴定结构加固裂缝处理

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高职院校学生自主创业现状问题及对策探析

晋城职业技术学院学报 2024年第2期17卷 27-29页

作者：徐建军晋城职业技术学院山西晋城048026

近年来,高职院校学生针对就业难的问题,在国家的倡导和鼓励下选择自主创业。本文从高职院校学生自主创业的意义、现状及面临的问题分析,从而提出改进高职院校学生自主创业现状的具体措施。

关键词：高职院校学生自主创业现状问题具体措施

萎缩芽胞杆菌LB6-2抑制立枯丝核菌活性物质的鉴定

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中国生物防治学报 2024年第2期40卷 378-387页

作者：罗文芳周军辉何伟许建军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/新疆农业生物安全重点实验室乌鲁木齐830091

本研究采用平板对峙法、菌丝生长速率法和菌核萌发抑制法筛选出一株细菌LB6-2,对立枯丝核菌的菌丝生长抑制率为71.76%,菌核萌发抑制率为100.00%。通过观察形态学特征、分析理化性质结合16S r DNA扩增序列分析对该菌株鉴定为萎缩芽胞杆菌... 详细信息

本研究采用平板对峙法、菌丝生长速率法和菌核萌发抑制法筛选出一株细菌LB6-2,对立枯丝核菌的菌丝生长抑制率为71.76%,菌核萌发抑制率为100.00%。通过观察形态学特征、分析理化性质结合16S r DNA扩增序列分析对该菌株鉴定为萎缩芽胞杆菌Bacillusatrophaeus(OK639005.1)。采用大孔树脂法提取发酵产物并进行HPLC制备,对获得的14个组分进行活性测定确定其活性组分,从活性组分中制备获得3个单品化合物LBN4-2、LBN4-4、LBN4-5,经HPLC-MS、NMR分析和活性测定结果表明,化合物LBN4-2为Cyclo(Pro-Val)、LBN4-4为Cyclo(D-Leu-L-Pro)和LBN4-5为Cyclo(L-prolyl-D-phenylalanyl),3个化合物的浓度在4 mmol/L时对立枯丝核菌菌丝生长的抑制率分别为86.16%、84.87%和83.10%,浓度在2 mmol/L以上时,对立枯丝核菌菌核萌发的抑制率为100%。由此可见,萎缩芽胞杆菌LB6-2具有作为防治立枯丝核菌生防菌剂研发的潜力。

关键词：立枯丝核菌萎缩芽胞杆菌活性物质结构鉴定