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离心式叶轮三维反问题设计和数值计算

排灌机械工程学报 2012年第6期30卷 632-635页

作者：杨魏王福军王宏中国农业大学水利与土木工程学院北京100083 清华大学核能技术与新能源技术研究院北京100084

为解决离心式叶轮传统设计方法主要依赖于设计者经验以及设计周期较长等问题,采用三维反问题设计方法,根据给定的流场进行叶轮形状的设计,从而提高设计过程对叶轮性能的控制能力.三维反问题设计方法基于无黏有势流假设,将三维速度场分... 详细信息

为解决离心式叶轮传统设计方法主要依赖于设计者经验以及设计周期较长等问题,采用三维反问题设计方法,根据给定的流场进行叶轮形状的设计,从而提高设计过程对叶轮性能的控制能力.三维反问题设计方法基于无黏有势流假设,将三维速度场分解为周向平均速度和周期速度进行求解,实现了在二维轴面流道上叶片形状和流场的三维计算.三维叶片形状根据速度在叶片表面满足滑移条件计算得到,同时获得该叶轮形状下其内部三维流场的计算结果.采用自编三维反问题设计程序进行了离心式叶轮的设计计算,并利用三维定常湍流数值计算技术对设计结果进行了流场模拟和性能评价,流场的模拟结果与设计方法计算结果定性吻合,验证了设计方法的有效性.研究结果表明:将三维反问题设计方法和三维湍流数值计算技术结合可有效缩短设计周期,提高设计质量,并可用于各种叶轮机械的设计.

关键词：离心叶轮反问题设计性能预测湍流模拟

Influence of the cobalt concentration on optical and magnetic properties of zinc oxide

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Chinese Science Bulletin 2010年第10期55卷 897-901页

作者： wang LiWei,ZHANG fujun,XU Zheng,ZHAO SuLing & LU LiFang Institute of Optoelectronics Technology,Beijing Jiaotong University Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University),Ministry of Education,Beijing 100044,China Institute of Optoelectronics Technology Beijing Jiaotong University Beijing China Ministry of Education Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Beijing China

A series of Co-doped ZnO thin films have been prepared by direct current reactive magnetron sputtering on glass *** structural characterization by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM) gave no evidence of second phase *** qualitative composition and chemical state were characterized by energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectronic spectrometry (XPS),*** results confirmed that Co was incorporated as Co3+,occupying the Zn2+ sites in ZnO's wurtzite *** luminescence properties of the films were investigated by room temperature photoluminescence,and the optical properties were studied by optical *** magnetic analysis was carried out at room temperature and at 50 K by Quantum Design MPMS (SQUID) *** results showed that all the Co-doped ZnO thin films prepared by direct current magnetron sputtering were not ferromagnetic above 50 K.

关键词：氧化锌钴氧化物磁性直流反应磁控溅射 X射线光电子能谱室温光致发光扫描电子显微镜纤锌矿结构

Delineating homogeneous domains of fractured rocks using topological manifolds and deep learning

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2996-3013页

作者： Yongqiang Liu Jianping Chen fujun Zhou Jiewei Zhan wanglai Xu Jianhua Yan College of Construction Engineering Jilin UniversityChangchun130026China China Railway First Survey and Design Institute Group Co. Ltd.Xi’an710043China College of Geological Engineering and Geomatics Chang’an UniversityXi’an710054China

Determining homogeneous domains statistically is helpful for engineering geological modeling and rock mass stability *** this text,a technique that can integrate lithology,geotechnical and structural information is proposed to delineate homogeneous *** technique is then applied to a high and steep slope along a ***,geological and geotechnical domains were described based on lithology,faults,and shear ***,topological manifolds were used to eliminate the incompatibility between orientations and other parameters(*** length and roughness)so that the data concerning various properties of each discontinuity can be matched and characterized in the same Euclidean ***,the influence of implicit combined effect in between parameter sequences on the homogeneous domains could be *** learning technique was employed to quantify abstract features of the characterization images of discontinuity properties,and to assess the similarity of rock mass *** results show that the technique can effectively distinguish structural variations and outperform conventional *** can handle multisource engineering geological information and multiple discontinuity *** technique can also minimize the interference of human factors and delineate homogeneous domains based on orientations or multi-parameter with arbitrary distributions to satisfy different engineering requirements.

关键词： Homogeneous domain Geological domain Geotechnical domain Structural domain Topological manifold Deep learning

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认识与展望:对可持续发展的多学科审视

理论前沿 2006年第15期 31-33页

作者：王福军国防大学政治部

作为一个对全球发展有着深远影响的社会发展理念,可持续发展已进入众多学科视域。本文分别从哲学、经济学、政治学、生态学角度探讨了可持续发展的学科内涵及实践价值。

关键词：可持续发展哲学经济学政治学生态学审视

管道式喷灌系统水力解析的改进前进(EFSM)算法

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农业工程学报 2005年第7期21卷 73-76页

作者：赵凤娇王福军中国农业大学水利与土木工程学院北京100083

分析了图解法、解析法和数解法等水力解析方法各自的特点,并着重比较了有限元法和Hathoot前进法等数解法的优点和局限性。根据前进法的基本思路,提出了管道式喷灌系统水力解析新方法——改进前进法(EFSM)。应用伯努力能量方程和达西-韦... 详细信息

分析了图解法、解析法和数解法等水力解析方法各自的特点,并着重比较了有限元法和Hathoot前进法等数解法的优点和局限性。根据前进法的基本思路,提出了管道式喷灌系统水力解析新方法——改进前进法(EFSM)。应用伯努力能量方程和达西-韦斯巴赫摩擦损失方程依次对干管和支管建立方程,通过逐步迭代将非线性方程线性化,并提出了针对梳齿形和干管单向布置的丰字形喷灌系统的水力解析步骤。

关键词：管道式喷灌系统水力解析改进前进法图解法解析法数解法

Linear Phase FIR Filter on Measuring 3-D Surface

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Semiconductor Photonics and Technology 1997年第2期3卷 29-34页

作者： wang Yunshan,YANG fujun,LI Wei (Shandong University of Technology,Jinan 250061,CHN)

An optical technology for 3-D surface measurement is set *** technology,based on a deformed projected grating pattern which carries the 3-D information of the measured object,can automatically and accurately obtain the phase map of a measured object by using a linear-phase FIR *** contrast to the 2-D fast Fourier transform technique,it’s more than *** one image pattern is sufficient for *** phase map can be processed without assigning fringe orders and making distinction between a depression and an *** analysis and experimental result are presented.

关键词： Linear-Phase FIR Filter Profilometry Projected Grating Image 3-D Surface

基于特殊分工基础上的产业内升级程度评价指标体系研究

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学术交流 2009年第12期 167-169页

作者：王福君鞍山师范学院辽宁鞍山114015

国内外学者对产业间升级程度评价指标体系已经做了深入的研究,但对于特殊分工基础上的产业内升级程度评价指标体系的研究相对还是一片空白。本文以装备制造业为研究对象,提出了装备制造业内部结构升级程度评价指标体系的构建原则,设计... 详细信息

国内外学者对产业间升级程度评价指标体系已经做了深入的研究,但对于特殊分工基础上的产业内升级程度评价指标体系的研究相对还是一片空白。本文以装备制造业为研究对象,提出了装备制造业内部结构升级程度评价指标体系的构建原则,设计了装备制造业内部结构升级程度评价指标体系,并进一步探讨了采用因子分析法来评价装备制造业内部结构升级程度的步骤。

关键词：产业内升级装备制造业评价指标因子分析法

Late Mesozoic tectonic evolution of the Chinese Tianshan and adjacent areas: Evidence from sedimentary provenance of the southeastern Junggar Basin

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Late Mesozoic tectonic evolution of the Chinese Tianshan and...

用静力简化方法计算地震作用下桥墩的弹塑性变形

作者： fujun wang Wenbin Zhu Meng Luo Yuanyuan Cao

The Tianshan Range and its adjacent areas were initially formed by the Paleozoic subduction - accretion of the Paleo-Asian Ocean and were reactivated by India - Asia collision during the Cenozoic. However, deciphering the Late Mesozoic tectonic evolution of this area remains a challenge due to the scarcity of data. Significantly, the effect of the Yanshan Movement,

关键词： Evidence from sedimentary provenance of the southeastern Junggar Basin Late Mesozoic tectonic evolution of the Chinese Tianshan and adjacent areas

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铁道标准设计 2010年第4期30卷 59-62页

作者：王富君中铁第五勘察设计院集团有限公司北京102600

在地震作用下,桥梁的动力响应有简单的,也有复杂的,在《公路桥梁抗震设计细则》(JTG/TB02—01—2008)(以下简称《细则》)中将其称为规则桥梁和非规则桥梁,对于规则桥梁可以采用一些简化的设计分析方法就可以很好地把握其在地震作用下的... 详细信息

在地震作用下,桥梁的动力响应有简单的,也有复杂的,在《公路桥梁抗震设计细则》(JTG/TB02—01—2008)(以下简称《细则》)中将其称为规则桥梁和非规则桥梁,对于规则桥梁可以采用一些简化的设计分析方法就可以很好地把握其在地震作用下的动力响应特征。根据能量守恒原则,结合《细则》相关条款的要求,介绍一种对规则桥梁进行抗震分析的简化方法,即分析桥墩的弹塑性变形。

关键词：桥墩抗震分析能量守恒自振周期塑性转角