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东北铁路冻土区路基病害整治的试验研究

中国铁路 2005年第10期 54-56页

作者：伊承贵周长义哈尔滨铁路局科委办哈尔滨铁路局齐齐哈尔科研所工程师黑龙江齐齐哈尔161002

分析大兴安岭地区多年冻土铁路路基病害产生的原因,介绍路基整治试验工程概况、整治路基病害采取的工程措施及工作原理,通过分析初步观测数据,可以看出采取的冻土路基病害整治措施是有效的。

关键词：既有东北铁路多年冻土路基病害整治措施试验研究病害整治冻土铁路冻土区东北大兴安岭地区

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组合式X、γ射线剂量报警仪的研制

无损检测 1994年第3期16卷 64-65页

作者：陈宁沈昌义周勇中国船舶工业总公司船舶工业研究所

介绍组合式X、γ射线剂量报警仪的工作原理、能量补偿及系统结构。该仪器具有使用简单、实用、安全、成本低等特点。

关键词：辐射剂量监测仪 X射线 γ射线

Parallel Physics-Informed Neural Networks Method with Regularization Strategies for the Forward-Inverse Problems of the Variable Coefficient Modified KdV Equation

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Journal of Systems Science & Complexity 2024年第2期37卷 511-544页

作者： zhou Huijuan School of Science Shanghai Maritime UniversityShanghai 201306China

This paper mainly introduces the parallel physics-informed neural networks(PPINNs)method with regularization strategies to solve the data-driven forward-inverse problems of the variable coefficient modified Korteweg-de Vries(VC-MKdV)*** the forward problem of the VC-MKdV equation,the authors use the traditional PINN method to obtain satisfactory data-driven soliton solutions and provide a detailed analysis of the impact of network width and depth on solving accuracy and ***,the author finds that the traditional PINN method outperforms the one with locally adaptive activation functions in solving the data-driven forward problems of the VC-MKdV *** for the data-driven inverse problem of the VC-MKdV equation,the author introduces a parallel neural networks to separately train the solution function and coefficient function,successfully addressing the function discovery problem of the VC-MKdV *** further enhance the network’s generalization ability and noise robustness,the author incorporates two regularization strategies into the *** amount of numerical experimental data in this paper demonstrates that the PPINNs method can effectively address the function discovery problem of the VC-MKdV equation,and the inclusion of appropriate regularization strategies in the PPINNs can improves its performance.

关键词： Data-driven forward-inverse problems parallel physics-informed neural networks regularization strategies variable coefficient modified KdV equation

Influence of stearic acid surface modification on flowability and agglomeration of battery grade Li_(2)CO_(3)powder

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Particuology 2024年第9期92卷 263-277页

作者： Ming zhou Lithium Industry Center Zhejiang New Era Zhongneng Technology Co.Ltd.Shaoxing312000China

This work investigates the flow and agglomeration behaviors of battery grade Li_(2)CO_(3)powder and the influence of stearic acid surface *** degree of agglomeration is directly related to the uniformity of Li_(2)CO_(3)and its powder *** to the Chinese National Nonferrous Metal Industry Standard,battery grade Li_(2)CO_(3)powder has D50 equal to 3–8μm which belongs to a micron-sized superfine ***,with the extension of storage time,the serious agglomeration phenomenon occurs due to the large specific surface area and rough and irregular powder *** Hausner ratio(HR)of the unmodified sample increases from 1.14 to 1.41,and the corresponding flowability is classified as good to ***,among samples with doping stearic acid,the optimum amount of it is 0.10 wt%which exhibits an extremely stable HR value from 1.14 to ***,after 156 days,the repose angle(AR)obtained for samples without surface modification and using 0.10 wt%stearic acid are calculated to be 49°and 28°,*** on the values of HR and AR,the flowability of the unmodified sample is poor while the sample modified with 0.10 wt%of stearic acid still maintain excellent powder flow ***,The LiMn_(2)O_(4)cathode material synthesized from modified Li_(2)CO_(3)powder with a stearic acid content of 0.10 wt%exhibits good crystallinity and comparable electrochemical performance to that prepared by commercial Li_(2)CO_(3).These results indicate that stearic acid has the potential to be an ideal modifier for battery grade Li_(2)CO_(3)powder that needs to be kept for a long time.

关键词： Battery grade Li_(2)CO_(3)powder Flowability Surface modification Stearic acid

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数字PCR技术及应用研究进展

生物工程学报 2017年第2期33卷 170-177页

作者：林佳琪苏国成苏文金周常义集美大学食品与生物工程学院福建厦门361021 厦门市食品科技研发检测中心福建厦门361021

数字PCR是继实时定量PCR之后新兴发展起来的一种绝对定量分析技术。通过将单个DNA分子转移入独立的反应室,PCR扩增反应后,对荧光信号进行检测分析,实现单分子的绝对定量。数字PCR技术摆脱了对标准曲线的依赖,具有更高灵敏度和准确度,在... 详细信息

数字PCR是继实时定量PCR之后新兴发展起来的一种绝对定量分析技术。通过将单个DNA分子转移入独立的反应室,PCR扩增反应后,对荧光信号进行检测分析,实现单分子的绝对定量。数字PCR技术摆脱了对标准曲线的依赖,具有更高灵敏度和准确度,在基因突变检测、拷贝数变异检测、微生物检测、转基因食品检测以及下一代测序等方面均得到广泛应用。本文介绍数字PCR技术的定量方法,并评述该技术在主要应用领域的研究进展。

关键词：数字PCR 绝对定量泊松分布突变检测拷贝数变异检测微生物检测转基因食品检测

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JWJ-C计轴系统研究

铁道通信信号 2010年第5期46卷 24-27页

作者：周长义哈尔滨铁路局科学技术研究所

JWJ-C计轴系统是以传感技术、计算机技术、通信技术为基础构成的铁路信号控制基础设备,是检查轨道区段占用或空闲状态的安全设备。通过介绍JWJ-C计轴系统的主要功能及技术特点,阐述了该系统的构成及原理,重点论述了该系统在安全性和可... 详细信息

JWJ-C计轴系统是以传感技术、计算机技术、通信技术为基础构成的铁路信号控制基础设备,是检查轨道区段占用或空闲状态的安全设备。通过介绍JWJ-C计轴系统的主要功能及技术特点,阐述了该系统的构成及原理,重点论述了该系统在安全性和可靠性等方面的特殊设计,并简要介绍了系统应用情况。

关键词：计轴系统安全性可靠性应用

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林核1号核桃在晋中市的综合评价

山西林业科技 2020年第3期49卷 15-17页

作者：周长义永和县林业局山西永和041400

对林核1号核桃的物候期、树体性状、结实特性、坚果品质进行调查。结果表明,林核1号在晋中地区萌芽期、果实成熟期较中林1号、辽宁1号早3 d^5 d.林核1号出仁率60.3%,取整仁率97%,该品种以短果枝结果为主,每果枝结果1个~3个;其中,单果枝... 详细信息

对林核1号核桃的物候期、树体性状、结实特性、坚果品质进行调查。结果表明,林核1号在晋中地区萌芽期、果实成熟期较中林1号、辽宁1号早3 d^5 d.林核1号出仁率60.3%,取整仁率97%,该品种以短果枝结果为主,每果枝结果1个~3个;其中,单果枝占58%,双果枝占40%,三果枝占2%,平均坐果率81.1%,表现出良好的丰产性能。

关键词：林核1号性状综合评价晋中市

Phase field modeling of ferroelastic variant switching in yttria-stabilized t'zirconia with strain gradient elasticity and interface tension

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Science China(Technological Sciences) 2024年第5期67卷 1443-1457页

作者： zhou QianQian WEI YueGuang zhou YiChun YANG Li College of Engineering BIC-ESATPeking UniversityBeijing100871China School of Advanced Materials and Nanotechnology Xidian UniversityXi’an710126China Frontier Research Center of Thin Films and Coatings for Device Applications Academy of Advanced Interdisciplinary ResearchXidian UniversityXi’an710126China

The 6–8 wt%yttria-stabilized zirconia with a tetragonal structure(t’-YSZ)is extensively employed in thermal barrier *** exceptional fracture toughness of t’-YSZ can be attributed to its distinctive ferroelastic toughening *** and interface tension play a critical role in ferroelastic variant switching at the micro-and *** paper presents an original thermodynamically consistent phase field(PF)theory for analyzing ferroelastic variant switching at the micro-and nano-scale of t’-*** theory incorporates strain gradient elasticity using higher-order elastic energy and interface tension tensor via geometric nonlinearity to represent biaxial tension resulting from interface ***,a mixed-type formulation is employed to implement the higher-order theory through the finite element *** an interface in equilibrium,the effects of strain gradient elasticity result in a more uniform distribution of stresses,whereas the presence of interface tension tensor significantly amplifies the stress magnitude at the *** introduction of an interface tension tensor increases the maximum value of stress at the interface by a factor of 4 to *** nucleation and evolution of variants at a pre-existing crack tip in a mono-phase t’-YSZ have also been *** strain gradient elasticity is capable of capturing the size effect of ferroelastic variant switching associated with microstructures in ***,when the grain size approaches that of the specimen,the critical load required for variant switching at the crack tip increases,resulting in greater dissipation of elastic energy during ferroelastic variant ***,the interface tension accelerates the evolution of *** presented framework exhibits significant potential in modeling ferroelastic variant switching at the micro-and nano-scale.

关键词： thermodynamics strain gradient elasticity interface tension phase field method ferroelastic variant switching

Deep-reinforcement-learning-based UAV autonomous navigation and collision avoidance in unknown environments

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Chinese Journal of Aeronautics 2024年第3期37卷 237-257页

作者： Fei WANG Xiaoping ZHU zhou zhou Yang TANG School of Astronautics Northwestern Polytechnical UniversityXi’an 710072China School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

In some military application scenarios,Unmanned Aerial Vehicles(UAVs)need to perform missions with the assistance of on-board cameras when radar is not available and communication is interrupted,which brings challenges for UAV autonomous navigation and collision *** this paper,an improved deep-reinforcement-learning algorithm,Deep Q-Network with a Faster R-CNN model and a Data Deposit Mechanism(FRDDM-DQN),is proposed.A Faster R-CNN model(FR)is introduced and optimized to obtain the ability to extract obstacle information from images,and a new replay memory Data Deposit Mechanism(DDM)is designed to train an agent with a better *** training,a two-part training approach is used to reduce the time spent on training as well as retraining when the scenario *** order to verify the performance of the proposed method,a series of experiments,including training experiments,test experiments,and typical episodes experiments,is conducted in a 3D simulation *** results show that the agent trained by the proposed FRDDM-DQN has the ability to navigate autonomously and avoid collisions,and performs better compared to the FRDQN,FR-DDQN,FR-Dueling DQN,YOLO-based YDDM-DQN,and original FR outputbased FR-ODQN.

关键词： Faster R-CNN model Replay memory Data Deposit Mechanism(DDM) Two-part training approach Image-based Autonomous Navigation and Collision Avoidance(ANCA) Unmanned Aerial Vehicle(UAV)