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铅铋堆燃料组件子通道计算方法优化

核技术 2024年第7期47卷 117-124页

作者：王言卢嘉鸣姚嘉晔洪钢张尧立厦门大学能源学院厦门361005

针对铅铋堆开展燃料组件子通道分析,对于铅铋堆的发展具有重要的意义。本研究的目的是修改和优化COBRA子通道程序,使其适用于铅铋反应堆,并验证其性能。修改包括调整物性参数、流换热模型、摩擦阻力模型以及湍流交混模型。然后将修改后... 详细信息

针对铅铋堆开展燃料组件子通道分析,对于铅铋堆的发展具有重要的意义。本研究的目的是修改和优化COBRA子通道程序,使其适用于铅铋反应堆,并验证其性能。修改包括调整物性参数、流换热模型、摩擦阻力模型以及湍流交混模型。然后将修改后的程序数值计算结果与实验数据进行比较。针对宽参数质量流量条件,提出了一种与神经网络相结合的子通道优化方法。结果表明:改进后的子通道程序在实验工况下与实验结果和FLUENT计算结果吻合良好。分析质量流量对计算精度的影响,发现神经网络可以提高计算精度。通过改进和神经网络优化子通道分析程序适用于宽参数质量流量工况下的铅铋堆子通道分析,可为铅铋堆的堆芯设计提供方法借鉴。

关键词：铅铋堆子通道分析带绕丝燃料组件神经网络计算流体力学

Anatomical and FTIR analyses of phloem and xylem of Tetracentron sinense

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Journal of Forestry Research 2017年第6期28卷 1264-1270页

作者： Jiangtao Shi Feng Wang yaoli zhang Collage of Material Science and Engineering Nanjing Forestry University Nanjing 210037 People’s Republic of China

The fast growth of Tetracentron sinense is a potential valuable timber resource, but whether its anatomy and chemical components are suitable for timber is unknown. We used light microscopy and SEM to examine the anatomical structure and FITR to measure the chemical components of the phloem and xylem of this tree. Radial variations in growth ring width and tracheid dimensions were also evaluated. The sieve tube, phloem parenchyma cell and sclereids clusters were the main cells in phloem, and the tracheid was the fundamental cell in xylem. An unusual tracheid type, fiber-tracheids or vessel-liked elements was visible. Wood rays nonstoried, uniseriate and multiseriate, including heterogeneous II, occasionally I, and usually 3-6 cells wide. The mean growth-ring width was 2.53 +/- 0.46 mm, and the percentage of late wood was over 60%. For radial variation, growth-ring width increased at an early growth stage, and reached the largest increment during years 11-15, then decreased. The maximum growth-ring width was 5.313 mm. During late growth (60-85 years), trees also maintained a high radial growth increment. Radial variation in the percentage of late wood was uniform, about 50-70%, throughout the growth years. Growth patterns in the length and width of early and late wood were similar as the trees aged. From the FTIR results, the chemical components differed significantly between xylem and phloem, hemicellulose in particular was higher in the xylem than in the phloem, where it was apparently absent. All of these suggest that the composition of phloem in T. sinense is very similar to that of hardwood, and it has higher growth ratio and uniform wood properties.

关键词： Phloem Radial variation Tracheid Tetracentron sinense Xylem

The interaction and migration of deformation twin in an eutectic high-entropy alloy AlCoCrFeNi2.1

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Journal of Materials Science & Technology 2019年第5期35卷 902-906页

作者： yaoli zhang Jinguo Li Xinguang Wang Yiping Lu Yizhou Zhou Xiaofeng Sun Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Hefei 230026 China Key Laboratory of Space Manufacturing Technology Chinese Academy of Sciences Beijing 100094 China School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China

An eutectic high-entropy alloy consisting Al, Co, Cr, Fe and Ni elements was prepared by vacuum directional solidification technology. The alloy exhibits excellent comprehensive mechanical performance during tension at temperature range of 600–700℃. The microstructure reveals the intersection of twintwin is the prevailing deformation mechanism and the twins play a dual role in strengthening and toughening the alloy in the thermomechanical process. The deformation twin variants I and were formed by the edge dislocation 112 and the mixed dislocation 211 on the {111} crystal planes, respectively. Besides, the dislocation jogs and kinks caused by twin intersection on the slip planes can strengthen the alloy, which may contribute to the high strength(the tensile strengths at the 600°and 700°tensile tests are respectively780 MPa and 630 MPa.). Moreover, the coherent twin boundary migration has the function of coordinating deformation and contributes to the high ductility of the alloy.

关键词： Eutectic high-entropy alloy Tensile properties Deformation twin Dislocation jog Twin migration

Service Function Chain Deployment Algorithm Based on Multi-Agent Deep Reinforcement Learning

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Computers, Materials and Continua 2024年第3期80卷 4875-4893页

作者： Huang, Wanwei zhang, Qiancheng Liu, Tao Xu, yaoli zhang, Dalei College of Software Engineering Zhengzhou University of Light Industry Zhengzhou 450007 China Henan Jiuyu Tenglong Information engineering Co. Ltd. Zhengzhou 450052 China Henan Xin’an Communication Technology Co. Ltd. Zhengzhou 450007 China

Aiming at the rapid growth of network services, which leads to the problems of long service request processing time and high deployment cost in the deployment of network function virtualization service function chain (SFC) under 5G networks, this paper proposes a multi-agent deep deterministic policy gradient optimization algorithm for SFC deployment (MADDPG-SD). Initially, an optimization model is devised to enhance the request acceptance rate, minimizing the latency and deploying the cost SFC is constructed for the network resource-constrained case. Subsequently, we model the dynamic problem as a Markov decision process (MDP), facilitating adaptation to the evolving states of network resources. Finally, by allocating SFCs to different agents and adopting a collaborative deployment strategy, each agent aims to maximize the request acceptance rate or minimize latency and costs. These agents learn strategies from historical data of virtual network functions in SFCs to guide server node selection, and achieve approximately optimal SFC deployment strategies through a cooperative framework of centralized training and distributed execution. Experimental simulation results indicate that the proposed method, while simultaneously meeting performance requirements and resource capacity constraints, has effectively increased the acceptance rate of requests compared to the comparative algorithms, reducing the end-to-end latency by 4.942% and the deployment cost by 8.045%. Copyright © 2024 The Authors. Published by Tech Science Press.

关键词： Network function virtualization

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木材微区结构表征方法及其研究进展

林产化学与工业 2018年第2期38卷 1-10页

作者：王旋刘竹张耀丽潘彪南京林业大学材料科学与工程学院江苏南京210037

介绍了木材细胞壁微区结构的表征方法,并重点阐述了X射线衍射技术、核磁共振技术、原子力显微镜技术和共聚焦显微拉曼光谱技术等4种表征方法在木材微区结构研究中的应用及研究现状,为今后木材超微结构的探索提供了方法与思路。进一步归... 详细信息

介绍了木材细胞壁微区结构的表征方法,并重点阐述了X射线衍射技术、核磁共振技术、原子力显微镜技术和共聚焦显微拉曼光谱技术等4种表征方法在木材微区结构研究中的应用及研究现状,为今后木材超微结构的探索提供了方法与思路。进一步归纳总结了4种表征技术的优势及局限性,并明确指出了木材微区结构研究在现阶段存在的不足与未来发展方向。

关键词：分析方法原位表征细胞壁超微结构应用展望

超临界二氧化碳再压缩布雷顿循环变工况特性分析

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原子能科学技术 2018年第9期52卷 1625-1634页

作者：杨映麟张尧立赵英汝郭奇勋厦门大学能源学院福建厦门361102

超临界二氧化碳再压缩布雷顿循环是高效紧凑的能量转换方式。目前许多研究在分析循环的特性时,常假设压缩机和透平的效率为恒定,该假设与实际情况差别很大。本文使用MODELICA作为工具,建立了超临界二氧化碳再压缩布雷顿循环模型。对于... 详细信息

超临界二氧化碳再压缩布雷顿循环是高效紧凑的能量转换方式。目前许多研究在分析循环的特性时,常假设压缩机和透平的效率为恒定,该假设与实际情况差别很大。本文使用MODELICA作为工具,建立了超临界二氧化碳再压缩布雷顿循环模型。对于压缩机和透平,加入了真实压缩机和透平的特性曲线模型。通过模拟计算发现,循环输入功率和循环流量的改变将对循环火用效率和各组件的火用损产生影响。循环偏离设计工况时,适当控制输入功率和循环流量可调节循环输出功率和火用效率。

关键词：超临界二氧化碳再压缩特性曲线火用效率偏离设计工况

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PCCSAP-3D程序压力场算法改进

计算物理 2012年第5期29卷 700-706页

作者：张尧立杨燕宁周志伟王岩清华大学核能与新能源技术研究院北京100084 国核华清(北京)核电技术研发中心有限公司北京100190

介绍大型先进压水堆安全壳专用分析程序PCCSAP-3D计算采用的方法,引入GMRES(Generalized MinimalRESidual)方法改进该程序的压力场算法.使用GMRES算法的实用变形,并采用合适的预处理技术,比较GMRES算法和ML-ADI算法在求解压力方程时的... 详细信息

介绍大型先进压水堆安全壳专用分析程序PCCSAP-3D计算采用的方法,引入GMRES(Generalized MinimalRESidual)方法改进该程序的压力场算法.使用GMRES算法的实用变形,并采用合适的预处理技术,比较GMRES算法和ML-ADI算法在求解压力方程时的收敛速度.结果表明,利用压力矩阵结构化和稀疏性的特点,采用预处理GMRES算法能够更快速地求解压力方程.当压力矩阵规模变大时,GMRES算法相对于ML-ADI方法能够节省更多的时间.

关键词：大型先进压水堆 PCCS GMRES ML-ADI

非能动安全壳冷却系统模拟分析程序PCCSAP-3D及其验证

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核动力工程 2016年第2期37卷 175-179页

作者：王岩杨燕宁张尧力周志伟清华大学核能与新能源技术研究院北京100084 国家核电技术研发中心北京100190

PCCSAP-3D是我国自主开发用于分析评价非能动安全壳冷却系统(PCCS)的专用程序。通过对AP1000反应堆系统进行建模,使用PCCSAP-3D模拟分析AP1000在假想的冷却剂丧失(LOCA)以及主蒸汽管道破裂事故(MSLB)等设计基准事故下非能动安全系统的... 详细信息

PCCSAP-3D是我国自主开发用于分析评价非能动安全壳冷却系统(PCCS)的专用程序。通过对AP1000反应堆系统进行建模,使用PCCSAP-3D模拟分析AP1000在假想的冷却剂丧失(LOCA)以及主蒸汽管道破裂事故(MSLB)等设计基准事故下非能动安全系统的运行瞬态,并与西屋公司开发的非能动冷却系统分析程序WGOTHIC的计算结果进行对比。分析结果显示,两者吻合良好,PCCS能够有效地将假想事故下安全壳内的压力控制在设计安全限值以下。初步验证PCCSAP-3D程序对于AP1000反应堆PCCS冷却性能评价的可用性。

关键词：非能动安全壳冷却系统(PCCS) 分析程序先进压水堆

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皮革专业市场营销策略及其实践应用

中国皮革 2021年第9期50卷 83-86页

作者：张姚丽陕西邮电职业技术学院陕西咸阳712000

皮革专业市场具有鲜明且独特的优势特性,可以低成本整合并重组皮革产业,使得皮革企业与市场需求顺利接轨,以此实现规模经济、营销网络、区域品牌等建设。但是由于专业市场过度开发,且营销策划经验匮乏,导致市场建设容易而经营难的局面... 详细信息

皮革专业市场具有鲜明且独特的优势特性,可以低成本整合并重组皮革产业,使得皮革企业与市场需求顺利接轨,以此实现规模经济、营销网络、区域品牌等建设。但是由于专业市场过度开发,且营销策划经验匮乏,导致市场建设容易而经营难的局面始终得不到缓解,从而给投资商带来了巨大损失。据此,以皮革专业市场海宁皮革城为例,对皮革专业市场的营销策略及其实践应用进行了深层解析,以期能够为专业市场积累丰富营销策划经验,为良好的市场经营局势提供一定帮助。

关键词：专业市场营销策划品牌建设营销推广