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期刊论文 9

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2022 2

2018 1

2016 1

2013 1

2008 2

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保序 2

逆序 2

MCDM决策 1

决策分析 1

发展前景 1

影响因素 1

微震震源定位 1

无关方案独立性 1

研究进展 1

线性分配方法 1

聚变中子源；场反等离子体；磁压缩；氘氘反应 1

规范化公式 1

逆时成像 1

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Time reversal method for guided wave inspection in pipes

DENG Fei, WU Bin, HE Cunfu

《机械工程前沿（英文）》 2008年第3卷第3期页码 251-260 doi: 10.1007/s11465-008-0050-1

摘要： The application of the time reversal method in pipe-like structures based on finite element method (FEM) is investigated. A steel pipe model measuring 70 mm × 3.5 mm is used to analyze the reflection coefficient of the (0,2) mode with the time reversal process. Simulation results show that the time reversal array method is beneficial to the improvement of the signal-to-noise ratio of a guided wave inspection system. As the intercepting window is widened, more energy is included in re-emitted signals, which leads to a large reflection coefficient of the (0,2) mode. In parallel, a circumferential locating method based on the time reversal method is described. The time reversal process used for guided wave inspection leads to the temporal and spatial focusing. When the time reversal signals are re-emitted, the angular profile obtained at the axial location of the defect can be used to determine the circumferential location of the defect. Except for a pipe with one defect, the circumferential locating method has been verified on another pipe model with two defects. Meanwhile, the elements number of the time reversal array has been discussed for enhancing the discrimination of the defect circumferential location.

关键词： reversal process beneficial circumferential location energy number

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TiO supported IrO for anode reversal tolerance in proton exchange membrane fuel cell

《能源前沿（英文）》 2022年第16卷第5期页码 852-861 doi: 10.1007/s11708-021-0811-7

摘要： Fuel starvation can occur and cause damage to the cell when proton exchange membrane fuel cells operate under complex working conditions. In this case, carbon corrosion occurs. Oxygen evolution reaction (OER) catalysts can alleviate carbon corrosion by introducing water electrolysis at a lower potential at the anode in fuel shortage. The mixture of hydrogen oxidation reaction (HOR) and unsupported OER catalyst not only reduces the electrolysis efficiency, but also influences the initial performance of the fuel cell. Herein, Ti₄O₇ supported IrO_x is synthesized by utilizing the surfactant-assistant method and serves as reversal tolerant components in the anode. When the cell reverse time is less than 100 min, the cell voltage of the MEA added with IrO_x/Ti₄O₇ has almost no attenuation. Besides, the MEA has a longer reversal time (530 min) than IrO_x (75 min), showing an excellent reversal tolerance. The results of electron microscopy spectroscopy show that IrO_x particles have a good dispersity on the surface of Ti₄O₇ and IrO_x/Ti₄O₇ particles are uniformly dispersed on the anode catalytic layer. After the stability test, the Ti₄O₇ support has little decay, demonstrating a high electrochemical stability. IrO_x/Ti₄O₇ with a high dispersity has a great potential to the application on the reversal tolerance anode of the fuel cell.

关键词： proton exchange membrane fuel cell (PEMFC) fuel starvation cell reverse reversal tolerance anode oxygen evolution reaction

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Flow, thermal, and vibration analysis using three dimensional finite element analysis for a flux reversal

B. VIDHYA,K. N. SRINIVAS

《能源前沿（英文）》 2016年第10卷第4期页码 424-440 doi: 10.1007/s11708-016-0423-9

摘要： This paper presents the simulation of major mechanical properties of a flux reversal generator (FRG) viz., computational fluid dynamic (CFD), thermal, and vibration. A three-dimensional finite element analysis (FEA) based CFD technique for finding the spread of pressure and air velocity in air regions of the FRG is described. The results of CFD are mainly obtained to fine tune the thermal analysis. Thus, in this focus, a flow analysis assisted thermal analysis is presented to predict the steady state temperature distribution inside FRG. The heat transfer coefficient of all the heat producing inner walls of the machine are evaluated from CFD analysis, which forms the main factor for the prediction of accurate heat distribution. The vibration analysis is illustrated. Major vibration sources such as mechanical, magnetic and applied loads are covered elaborately which consists of a 3D modal analysis to find the natural frequency of FRG, a 3D static stress analysis to predict the deformation of the stator, rotor and shaft for different speeds, and an unbalanced rotor harmonic analysis to find eccentricity of rotor to make sure that the vibration of the rotor is within the acceptable limits. Harmonic analysis such as sine sweep analysis to identify the range of speeds causing high vibrations and steady state vibration at a mode frequency of 1500 Hz is presented. The vibration analysis investigates the vibration of the FRG as a whole, which forms the contribution of this paper in the FRG literature.

关键词： flux reversal generator air velocity computation fluid dynamics thermal analysis vibration analysis finite element analysis

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The effects of festivals and special events on city image design

LIU Yuan, CHEN Chong

《结构与土木工程前沿（英文）》 2007年第1卷第2期页码 255-259 doi: 10.1007/s11709-007-0032-0

摘要： City marketing provides a good vehicle to strengthen a city in competition. On the analysis of the important roles of events and city image in the context of city marketing, this paper suggests that holding festivals or special events is an effective approach to enhance city marketing. The positive impacts of festivals and special events, such as the identification of city image, the promotion of the transmission of city image, and the reversal of the negative image of the city, are discussed. The negative impacts of festivals and special events are also talked about. The unique image of the city could be identified by the City Mind Identity, the City Visual Identity and the City Behavior Identity concerned with festivals and special events.

关键词： Visual Identity reversal transmission marketing Behavior Identity

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A logic-based controller for the mitigation of ventilation air methane in a catalytic flow reversal reactor

Zhikai LI, Zhangfeng QIN, Yagang ZHANG, Zhiwei WU, Hui WANG, Shuna LI, Mei DONG, Weibin FAN, Jianguo WANG

《化学科学与工程前沿（英文）》 2013年第7卷第3期页码 347-356 doi: 10.1007/s11705-013-1347-0

摘要： The control system of a catalytic flow reversal reactor (CFRR) for the mitigation of ventilation air methane was investigated. A one-dimensional heterogeneous model with a logic-based controller was applied to simulate the CFRR. The simulation results indicated that the controller developed in this work performs well under normal conditions. Air dilution and auxiliary methane injection are effective to avoid the catalyst overheating and reaction extinction caused by prolonged rich and lean feed conditions, respectively. In contrast, the reactor is prone to lose control by adjusting the switching time solely. Air dilution exhibits the effects of two contradictory aspects on the operation of CFRR, i.e., cooling the bed and accumulating heat, though the former is in general more prominent. Lowering the reference temperature for flow reversal can decrease the bed temperature and benefit stable operation under rich methane feed condition.

关键词： ventilation air methane reverse flow reactor lean methane combustion logic-based controller mathematical modeling

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线性分配方法的逆序问题研究

章玲,周德群

《中国工程科学》 2008年第10卷第2期页码 50-53

摘要：

指出了线性分配方法的决策结果可能产生逆序，然后提出排序向量和相对分配比的概念，以分析线性分配方法决策结果产生逆序的原因，并在此基础上构建顺序线性分配方法，最后通过算例验证顺序线性分配方法决策结果的保序性。

关键词：决策分析线性分配方法逆序保序

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应用规范化公式的MCDM保序研究

章玲,周德群,李洪伟,朱佩枫

《中国工程科学》 2006年第8卷第12期页码 85-88

摘要：

规范化公式的应用会破坏方案之间的独立性，导致逆序的产生。提出了两种改进规范化公式的方法以消除逆序，并以加权算术平均（WAA）集结算子的多属性决策分析(MCDM)为例验证了所提出方法的合理性和有效性。改进后的规范化公式不仅可以应用于WAA算子，还可以应用到其他类似的决策算子中。改进后规范化公式的应用可以降低和消除规范化公式对无关方案独立性的影响，使得MCDM决策过程更加合理、科学。

关键词： MCDM决策规范化公式无关方案独立性保序逆序

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矿山微震震源定位研究进展与展望 Review

程久龙,宋广东,孙晓云,温来福,李飞

《工程（英文）》 2018年第4卷第5期页码 653-660 doi: 10.1016/j.eng.2018.08.004

摘要：

震源定位是微震监测技术的核心要素，微震震源定位的准确性关系到微震技术的应用效果。针对矿山微震波场特征，分析了矿山微震定位的特点，指出了基于到时的经典定位方法用于矿山微震定位存在的不足。介绍了近几年来在矿山微震定位方面的研究进展，主要包括Geiger 方法与线性方法联合定位、联合微震事件定位、相对定位法优化、无需预先测速的定位方法、无需拾取初至到时的定位方法，分析各方法的优缺点和可行条件。分析了检波器布置、初至到时拾取、波速模型对微震震源定位的影响，提出了应对措施。解决上述问题的方法包括采用新型融合、组合优化已有的方法、创建新方法以实现高精度微震震源定位。提出了矿山微震精确定位的发展方向，即速度模型优化、逆时成像、被动时间反转镜法、相对干涉成像法等新方法的应用，有望大大提高矿山微震震源定位精度。同时，探讨了多方法多参数信息融合和深度学习在矿山微震定位中的应用前景。这些创新性的微震震源定位方法具有广阔的发展前景。

关键词：微震震源定位影响因素逆时成像研究进展发展前景

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基于场反位形的磁约束氘氘脉冲聚变中子源方案设计

潘垣 ,王之江 ,武松涛 ,张明 ,陈志鹏 ,饶波 ,朱平,杨勇,丁永华

《中国工程科学》 2022年第24卷第3期页码 205-213 doi: 10.15302/J-SSCAE-2022.03.021

摘要：

聚变中子源可以真实反映材料在聚变中子辐照下的特性变化，对于开展聚变堆材料测试具有重要意义。基于加速器打靶原理的国际聚变材料辐照装置（IFMIF）与理想聚变中子源在聚变中子能谱等方面仍有一定差异，因此需对聚变中子源方案进行新的思索。本文围绕磁约束聚变中子源开展了磁场位形、加热方案设计与相关计算，分析了场反等离子体在两级级联磁压缩后的等离子体温度、密度演化过程及相应的中子产额，并研究了考虑双流体效应与有限拉莫尔半径效应后场反等离子体倾斜模、旋转模等磁流体不稳定性的抑制情况，最终给出了氘氘脉冲聚变中子源的关键物理参数。研究结果表明，该中子源有望获得年均2 MW/m²以上的高通量密度的聚变中子，能够满足商业聚变示范堆材料测试要求；经功率估算显示，基于场反位形进行两级级联磁压缩的新型聚变中子源方案还具备成为氘氘脉冲聚变能源的应用前景。

关键词：聚变中子源；场反等离子体；磁压缩；氘氘反应

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标题作者时间类型操作

Time reversal method for guided wave inspection in pipes

DENG Fei, WU Bin, HE Cunfu

期刊论文

TiO supported IrO for anode reversal tolerance in proton exchange membrane fuel cell

期刊论文

Flow, thermal, and vibration analysis using three dimensional finite element analysis for a flux reversal

B. VIDHYA,K. N. SRINIVAS

期刊论文

The effects of festivals and special events on city image design