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A Dynamic XML-NS View based Approach for the Extensible Integration of Web Data Sources

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Wuhan University Journal of Natural Sciences 2004年第5期9卷 647-651页

作者： WUWei LUZheng-ding LIRui-xuan WANGZhi-gang SchoolofComputerScienceandTechnology.HuazhongUniversityofScienceandTechnology Wuhan430071Hubei.China

We propose a three-step technique to achieve this purpose. First, we utilize a collection of XML namespaces organized into hierarchical structure as a medium for expressing data semantics. Second, we define the format of resource descriptor for the information source discovery scheme so that we can dynamically register and/or deregister the Web data sources on the fly. Third, we employ an inverted-index mechanism to identify the subset of information sources that are relevant to a particular user query. We describe the design, architecture, and implementation of our approach—IWDS, and illustrate its use through case examples. Key words integration - heterogeneity - Web data source - XML namespace CLC number TP 311.13 Foundation item: Supported by the National Key Technologies R&D Program of China(2002ba103A04)Biography: WU Wei (1975-), male, Ph.D candidate, research direction: information integration, distribute computing

关键词： integration heterogeneity Web data source XML namespace

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高频响应下音圈电机复杂迟滞特性建模与验证

振动与冲击 2012年第9期31卷 107-112页

作者：党选举王占军杨大磊桂林电子科技大学电子工程与自动化学院桂林541004

为实现音圈电机(Voice Coil Motor,VCM)在高频、高速、高加速情况下的精确定位控制,针对引起音圈电机产生振动、系统不稳定等问题的特殊复杂迟滞特性,建立其复杂迟滞模型。改进C-S迟滞模型,提出C-S神经网络混合动态复杂迟滞模型;用音圈... 详细信息

为实现音圈电机(Voice Coil Motor,VCM)在高频、高速、高加速情况下的精确定位控制,针对引起音圈电机产生振动、系统不稳定等问题的特殊复杂迟滞特性,建立其复杂迟滞模型。改进C-S迟滞模型,提出C-S神经网络混合动态复杂迟滞模型;用音圈电机的两组实测数据验证模型的有效性。实验结果为:音圈电机工作在低频、低速、低加速时(10 Hz)表现出一般的迟滞特性,这时建模的最大误差为4.8μm,是最大输出值的0.48%,表明该方法能够有效地补偿音圈电机一般的迟滞特性;音圈电机工作在高频、高速、高加速时(40 Hz)表现出特殊的复杂迟滞特性,其建模的最大误差为6μm,是最大输出值的0.97%。说明该方法能够满足复杂迟滞特性建模的要求。

关键词：音圈电机复杂迟滞神经网络 C-S模型非单调

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高分子湿度传感器的湿滞建模与智能补偿

传感器与微系统 2006年第7期25卷 43-45,49页

作者：严斌党选举桂林电子工业学院计算机系广西桂林541004 桂林电子工业学院智能系统与工业控制研究室广西桂林541004

高分子湿度传感器在测量过程中由于存在着湿滞特性影响了其测量的精度。根据湿滞特性表现出的分段线性性质与T-S模糊建模原理的相似性,提出利用T-S模糊建模的思想对高分子湿度传感器的湿滞非线性环节进行建模,进而建立起湿滞环节的逆模... 详细信息

高分子湿度传感器在测量过程中由于存在着湿滞特性影响了其测量的精度。根据湿滞特性表现出的分段线性性质与T-S模糊建模原理的相似性,提出利用T-S模糊建模的思想对高分子湿度传感器的湿滞非线性环节进行建模,进而建立起湿滞环节的逆模型,并采用其逆模型实现对湿滞环节的智能补偿。仿真结果表明:经湿滞补偿后,高分子湿度传感器的湿滞由5.56%RH减小到0.045%RH。

关键词：高分子湿度传感器湿滞特性 T-S模糊模型逆模型

Structural, Optical and Photocatalytic Properties of Cu²⁺ Doped ZnO Nanorods with Using HMTA Solvent Prepared by Hydrothermal Method

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Journal of Materials Science and Chemical Engineering 2023年第7期11卷 20-30页

作者： Nguyen Thi Tuyet Mai Nguyen Thi Lan Trinh xuan Anh Ta Ngoc Dung Huynh dang Chinh School of Chemical Engineering Hanoi University of Science and Technology Hanoi Vietnam

In this experiment, Cu2+ doped ZnO (Cu-ZnO) nanorods materials have been fabricated by hydrothermal method. Cu2+ ions were doped into ZnO with ratios of 2, 5 and 7 mol.% (compared to the mole’s number of Zn2+). The hexamethylenetetramine (HMTA) solvent used for the fabrication of Cu-ZnO nanorods with the mole ratio of Zn2+:HMTA = 1:4. The characteristics of the materials were analyzed by techniques, such as XRD, Raman shift, SEM and UV-vis diffuse reflectance spectra (DRS). The photocatalytic properties of the materials were investigated by the decomposition of the methylene blue (MB) dye solution under ultraviolet light. The results show that the size of Cu-ZnO nanorods was reduced when the Cu2+ doping ratio increased from 2 mol.% to 7 mol.%. The decomposition efficiency of the MB dye solution reached 92% - 97%, corresponding to the Cu2+ doping ratio changed from 2 - 7 mol.% (after 40 minutes of ultraviolet irradiation). The highest efficiency for the decomposition of the MB solution was obtained at a Cu2+ doping ratio of 2 mol.%.

关键词： Cu2+ Doped ZnO Nanorods ZnO Nanomaterials Hexamethylenetetramine (HMTA) Photocatalytics Methylene Blue Hydrothermal Method UV Irradiation

Comparison of microstructure and mechanical properties of titanium/ steel composite plates by two manufacturing processes

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Journal of Iron and Steel Research International 2018年第3期25卷 347-356页

作者： xuan Yang Chang-gen Shi Yu-heng Ge Md Nahid Hasan Sabuj Army Engineering University of PLA Nanjing 210007 Jiangsu China

Two types of titanium/steel composite plates with the same thickness were manufactured by parallel explosive welding and double vertical explosive welding and rolling, respectively. The comparative analysis of microstructure showed that the interface of double vertical explosive welding plate （B plate） tended to be straight while the interface of parallel explosive welding plate （A plate） was wavy bonding. Defects near the interface of B plate were extruded, and the thickness of the diffusion layer of B plate was thicker under the effects of preheating temperature and press-working. Comparative tests of mechanical properties indicated that the tensile shear strength of B plate was lower while its micro-hardness was higher. Specimens of these two types of plates were neither separated nor cracked after bending up to 180° in the three-point bending test. From the microstructural observation of tensile fracture characteristics, A plate had strong toughness fracture while B plate had mainly ductile fracture with cleavage fracture as the supplement. Macroscopically, the tensile strength of the latter was 7.9% less than that of the former. However, both satisfied the Chinese standard of tensile strength.

关键词： Double vertical explosive welding Hot rolling Parallel explosive welding Titanium/steel composite plate Microstructure Mechanical property

多调机环境下的树枝形铁路专用线作业车同步取送优化

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中国管理科学 2022年第4期30卷 228-239页

作者：李冰党佳俊轩华郑州大学管理工程学院河南郑州450001

围绕服务铁路枢纽地方货物流的小运转作业系统,研究一类多调机环境下的树枝形铁路专用线作业车同步取送优化问题。考虑取送顺序间隔、调机牵引能力等约束条件,以调机作业均衡为上层优化目标,以调机取送成本和货车停留成本最小化为下层... 详细信息

围绕服务铁路枢纽地方货物流的小运转作业系统,研究一类多调机环境下的树枝形铁路专用线作业车同步取送优化问题。考虑取送顺序间隔、调机牵引能力等约束条件,以调机作业均衡为上层优化目标,以调机取送成本和货车停留成本最小化为下层优化目标建立双重目标规划模型。根据模型特点,提出融合综合关联度和异步启发式过程的两阶段融合求解方法。该方法首先基于聚类划分思想,引入综合关联度确定调机最佳数量,并对作业区进行划分,从而为调机指派作业范围。进而基于迭代寻优思路,设计异步循环启发式过程,该过程根据多调机取送车作业特点赋予循环体表述,设计循环体更新规则,引入遗传算法中的交叉与变异操作对循环体进行寻优,进而导入人工鱼群聚群行为实现循环体二次寻优,从而完成所有调机在各自作业区内取送顺序的逐步寻优过程。最后,设计实验场景对所提出的两阶段算法进行过程验证,并设计不同规模试验进行对比测试,结果表明了所提算法的有效性和较优性。

关键词：树枝形专用线多调机小运转列车取送车

Attempted preparation of La_(0.5)ba_(0.5)MnO_(3-δ) leading to an in-situ formation of manganate nanocomposites as a cathode for proton-conducting solid oxide fuel cells

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Journal of Advanced Ceramics 2023年第6期12卷 1189-1200页

作者： Rui Zhou Yanru Yin Hailu Dai xuan Yang Yueyuan Gu Lei Bi School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China School of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China

A La_(0.5)ba_(0.5)MnO_(3-δ) oxide was prepared using the sol-gel *** of a pure phase,La_(0.5)ba_(0.5)MnO_(3-δ) was discovered to be a combination of La_(0.7)ba_(0.3)MnO_(3-δ) and baMnO_(3).The in-situ production of La_(0.7)ba_(0.3)MnO_(3-δ)+baMnO_(3) nanocomposites enhanced the oxygen vacancy(Vo)formation compared to single-phase La_(0.7)ba_(0.3)MnO_(3-δ) or baMnO_(3),providing potential benefits as a cathode for fuel ***,La_(0.7)ba_(0.3)MnO_(3-δ)+baMnO_(3) nanocomposites were utilized as the cathode for proton-conducting solid oxide fuel cells(H-SOFCs),which significantly improved cell *** 700 C,H-SOFC with a La_(0.7)ba_(0.3)MnO_(3-δ)+baMnO_(3) nanocomposite cathode achieved the highest power density(1504 mW·cm^(-2))yet recorded for H-SOFCs with manganate *** performance was much greater than that of single-phase La_(0.7)ba_(0.3)MnO_(3-δ)or baMnO_(3) cathode *** addition,the cell demonstrated excellent working ***-principles calculations indicated that the La_(0.7)ba_(0.3)MnO_(3-δ)/baMnO_(3) interface was crucial for the enhanced cathode *** oxygen reduction reaction(ORR)free energy barrier was significantly lower at the La_(0.7)ba_(0.3)MnO_(3-δ)/baMnO_(3) interface than that at the La_(0.7)ba_(0.3)MnO_(3-δ) or baMnO_(3) surfaces,which explained the origin of high performance and gave a guide for the construction of novel cathodes for H-SOFCs.

关键词： La_(0.5)ba_(0.5)MnO_(3-δ) nanocomposites cathode proton conductor solid oxide fuel cells(SOFCs)

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数控机床热误差补偿最佳转速选择

光学精密工程 2015年第11期23卷 3176-3182页

作者：苗恩铭吕玄玄苗继超党连春合肥工业大学仪器科学与光电工程学院安徽合肥230009

为提高数控机床热误差补偿模型在实际工程应用中的补偿精度和稳健性,研究了热误差补偿建模时机床最佳转速状态的选择方法。首先,以Leaderway V-450数控加工中心主轴Z向为研究对象,控制机床主轴在空转状态下,以图谱和恒定转速两种方式进... 详细信息

为提高数控机床热误差补偿模型在实际工程应用中的补偿精度和稳健性,研究了热误差补偿建模时机床最佳转速状态的选择方法。首先,以Leaderway V-450数控加工中心主轴Z向为研究对象,控制机床主轴在空转状态下,以图谱和恒定转速两种方式进行了多批次实验。然后,采用模糊聚类结合灰色关联度选择温度敏感点并建立多元线性回归模型。最后,分析不同转速类型下模型的预测效果并对同种转速类型下模型预测效果进行相对评价,从而给出热误差补偿建模时机床最佳转速状态的选择方法。实验结果表明,根据国际标准中不同主轴转速类型建立的热误差补偿模型,对于机床热误差预测效果存在较大差异。根据实际工程应用选择的最佳转速状态建立的补偿模型有较好的预测效果。

关键词：数控机床热误差主轴转速多元回归模型预测效果

Lower limit law of welding windows for explosive welding of dissimilar metals

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Journal of Iron and Steel Research International 2017年第8期24卷 852-857页

作者： Chang-gen Shi xuan Yang Yu-heng Ge Jun You Hong-bao Hou PI.A University of Science and Technology Nanjing 210007JiangsuChina baicheng Ordnance Test Center Baicheng 137001JilinChina

The influence of explosive charge thickness on the quality of explosive welding of dissimilar metals was *** lower limit law should be followed in the course of explosive *** welding experiments of stainless steel（410S）and steel（Q345R）were carried out in three different kinds of explosive charge thicknesses,namely 15,25and *** of morphology and mechanical properties of three samples were observed and *** was found that micro and small wavy bonding is mainly formed for charge thickness of 15mm whose strength is the highest with minor deformation and few defects in the interface;small and middle wavy bonding are mainly formed for charge thickness of 25 mm whose strength is comparatively mediocre;big wavy bonding is mainly formed for charge thickness of 35 mm whose strength is the *** cause of high bonding strength of the micro and small wavy interface was analyzed and verified on the basis of the results of Electron Probe Micro-Analyzer（EPMA）tests of three selected samples.

关键词： Explosive welding Welding window Lower limit law Cladding plate Bonding interface