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Wideband dispersion removal and mode separation of Lamb waves based on two-component laser interferometer measurement 被引量:2
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作者 徐琰锋 胡文祥 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期261-268,共8页
Ultrasonic Lamb waves are considered as a sensitive and effective tool for nondestructive testing and evaluation of plate-like or pipe-like structures. The nature of multimode and dispersion causes the wave packets to... Ultrasonic Lamb waves are considered as a sensitive and effective tool for nondestructive testing and evaluation of plate-like or pipe-like structures. The nature of multimode and dispersion causes the wave packets to spread, and the modes overlap in both time and frequency domains as they propagate through the structures. By using a two-component laser interferometer technique, in combination with a priori knowledge of the dispersion characteristics and wave structure information of Lamb wave modes, a two-component signal processing technique is presented for implementing dispersion removal and mode separation simultaneously for two modes mixture signals of Lamb waves. The proposed algorithm is first processed and verified using synthetic Lamb wave signals. Then, the two-component displacements test experiment is conducted using different aluminum plate samples. Moreover, we confirm the effectiveness and robustness of this method. 展开更多
关键词 Lamb wave dispersion compensation mode separation two-component measurement
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Characterization of Flame Retardancy and Oil-Water Separation Capacity of Superhydrophobic Silylated Melamine Sponges
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作者 Yongchun Liu Ni Qiao +7 位作者 Yanli Yang Yanchun Li Chunxiao He Siyang Wang Chengcheng Liu Ruixia Lei Wang Li Wenwen Gao 《Fluid Dynamics & Materials Processing》 EI 2024年第2期383-400,共18页
A silylated melamine sponge(SMS)was prepared by two simple steps,namely,immersion and dehydration of a melamine sponge coated with methyltrichlorosilane.The silylated structure of SMS was characterized by FT-IR(Fourie... A silylated melamine sponge(SMS)was prepared by two simple steps,namely,immersion and dehydration of a melamine sponge coated with methyltrichlorosilane.The silylated structure of SMS was characterized by FT-IR(Fourier-transform infrared)spectroscopy,SEM(Scanning electron microscopy)and in terms of water contact angles.Its oil-water absorption and separation capacities were measured by FT-IR and UV-visible spectrophoto-metry.The experimental results have shown that oligomeric silanol covalently bonds by Si-N onto the surface of melamine sponge skeletons.SMS has shown superhydrophobicity with a water contact angle exceeding 150°±1°,a better separation efficiency with regard to diesel oil(by 99.31%(wt/wt%)in oil-water mixture and even up to 99.99%(wt/wt%)for diesel oil in its saturated aqueous solution.Moreover,SMS inherited the intrinsicflame retardancy of the melamine sponge.In general,SMS has shown superhydrophobicity,high porosity,excellent selectivity,remarkable recyclability,and better absorption capacity for various oils and organic solvents,and a high separation efficiency for oil in saturated aqueous solutions. 展开更多
关键词 METHYLTRICHLOROSILANE silylated melamine sponge(smS) SUPERHYDROPHOBICITY absorption capacity oil-water separable efficiency flame retardancy
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SEPARATING BROWN AND BLACK BEARS IN NORTHEAST CHINA USING TOOTH MEASUREMENTS
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作者 姜兆文 郑红 +1 位作者 王玉玺 张淑云 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1995年第2期58-60,共3页
An expeditious method for ascertaining species between black bear (Selenarctos thibetanus G. cuiver) and brown bear (Ursus arctos Linnaeus) was developed using tooth measurements from previously identified specimens. ... An expeditious method for ascertaining species between black bear (Selenarctos thibetanus G. cuiver) and brown bear (Ursus arctos Linnaeus) was developed using tooth measurements from previously identified specimens. The measurement and analysis on 18 tooth measurement indexes (i.e. T1. Length of Pm1-Pm4, T2. L. of M1-M3, T3. M1L., T4. M1 width, T5. M2L., T6. M2W., T7.M3L., T8. M3W., T9. L. of C1 alveolus, T10. W. of C1 alveolus, T11. L. of C1-M2, T12. L. of Pm4 M2,T13.M1L., T14. M1W., T15. M2L., T16. M2W., T17.L. of C1 alveolus, T18. W. of C1 alveolus) of 59 skulls (black bears 25, brown bears 34) indicates that there are significant or the most significant difference between two species in every indexes, however T1, T9, T10, T17 and T18 are not suitable for species discriminator because of their high percent of overlap. The efficient species discriminators and standards (mm) are as follows T2(63.0), T3(22.0), T4(10.2), T5(23.8), T6(13.6), T7(18.0), T8(13.5), T11(110.0),T12(66.0), T13(20. 1), T14(15.8), T15(33.0) and T16(17.3). Those who are less than or equal to standard are classified to black bear, the others are brown bear. The method is very convenient and useful with high reliability. Their lowest accuracy percent are 95.0%, most of them over 97%. Different indexes will be chosen refer to the degree of specimen destroyed. 展开更多
关键词 BLACK BEAR (Selenarctos thibetanus) BROWN BEAR (Ursus arctos) TOOTH measurement separATING
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INVESTIGATION OF PULSED-WIRE TECHNIQUE FOR WALL PARAMETERS MEASUREMENT IN SEPARATED FLOWS
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作者 Liao Yufeng, Xu Cheng(Mechanical Engineering Institute, Nanjing University of Scienceand Technology, Nanjing, 210094, China) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1997年第2期98-103,共6页
A pulsed-wire wall probe measurement system was developed in this paper,which can be used for measuring wall Parameters in separated flow- The operating princi-ple was described and the way of probe calibration was gi... A pulsed-wire wall probe measurement system was developed in this paper,which can be used for measuring wall Parameters in separated flow- The operating princi-ple was described and the way of probe calibration was given. Wall parameters of back-ward-facing and forward-facing step flow were measured,and the wall nows structure andcharacters were revealed. 展开更多
关键词 separated flow measureMENT pulse heating wall parameters pulsed-wire wall probe
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Accurate vision measurement for kinematic parameters of satellite separation tests
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作者 胡星志 朱肇昆 陈小前 《Journal of Central South University》 SCIE EI CAS 2013年第7期1825-1831,共7页
The accurate measurement of kinematic parameters in satellite separation tests has great significance in evaluating separation performance. A novel study is made on the measuring accuracy of monocular and binocular, w... The accurate measurement of kinematic parameters in satellite separation tests has great significance in evaluating separation performance. A novel study is made on the measuring accuracy of monocular and binocular, which are the two main vision measurement methods used for kinematic parameters. As satellite separation process is transient and high-dynamic, it will bring more extraction errors to the binocular. Based on the design approach of intersection measure and variance ratio, the monocular method reflects higher precision, simpler structure and easier calibration for level satellite separation. In ground separation tests, a high-speed monocular system is developed to gain and analyze twelve kinematic parameters of a small satellite. Research shows that this monocular method can be widely applied for its high precision, with position accuracy of 0.5 mm, speed accuracy of 5 mm/s, and angular velocity accuracy of 1 (°)/s. 展开更多
关键词 运动学参数 分离试验 精确测量 小卫星 测量精度 视力 运动参数 分离性能
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基于F-measure的生活垃圾分类效果评价指标优化研究
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作者 杨龑 陈海滨 +1 位作者 杨禹 朱斌 《环境卫生工程》 2018年第3期1-3,共3页
基于分类器特征及其性能评价指标F-measure,在此前研究的基础上对生活垃圾源头分类实际效果评价指标进行优化、改进,提出了生活垃圾源头分类综合效果指数Sp。该指标不仅能统一源头分类效果信息,还可通过参数λ的设置反映决策者所关心的... 基于分类器特征及其性能评价指标F-measure,在此前研究的基础上对生活垃圾源头分类实际效果评价指标进行优化、改进,提出了生活垃圾源头分类综合效果指数Sp。该指标不仅能统一源头分类效果信息,还可通过参数λ的设置反映决策者所关心的问题。实例研究证明该指标具有良好的适用性。 展开更多
关键词 生活垃圾 源头分类 分类器 评价指标 F-measure
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On-Machine Measurement of the Straightness and Tilt Errors of a Linear Slideway Using a New Four-Sensor Method 被引量:3
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作者 Lei Zhao Kai Cheng +1 位作者 Hui Ding Liang Zhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第2期122-132,共11页
Although there are some multi-sensor methods for measuring the straightness and tilt errors of a linear slideway, they need to be further improved in some aspects, such as suppressing measurement noise and reducing pr... Although there are some multi-sensor methods for measuring the straightness and tilt errors of a linear slideway, they need to be further improved in some aspects, such as suppressing measurement noise and reducing precondition.In this paper, a new four-sensor method with an improved measurement system is proposed to on-machine separate the straightness and tilt errors of a linear slideway from the sensor outputs, considering the influences of the reference surface profile and the zero-adjustment values. The improved system is achieved by adjusting a single sensor to di erent positions. Based on the system, a system of linear equations is built by fusing the sensor outputs to cancel out the e ects of the straightness and tilt errors. Three constraints are then derived and supplemented into the linear system to make the coe cient matrix full rank. To restrain the sensitivity of the solution of the linear system to the measurement noise in the sensor outputs, the Tikhonov regularization method is utilized. After the surface profile is obtained from the solution, the straightness and tilt errors are identified from the sensor outputs. To analyze the e ects of the measurement noise and the positioning errors of the sensor and the linear slideway, a series of computer simulations are carried out. An experiment is conducted for validation, showing good consistency. The new four-sensor method with the improved measurement system provides a new way to measure the straightness and tilt errors of a linear slideway, which can guarantee favorable propagations of the residuals induced by the noise and the positioning errors. 展开更多
关键词 MULTI-SENSOR method STRAIGHTNESS ERROR TILT ERROR On-machine measurement LINEAR slideway ERROR separation technique
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A novel similarity measure between intuitionistic fuzzy sets based on the mid points of transformed triangular fuzzy numbers with applications to pattern recognition and medical diagnosis 被引量:3
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作者 J Dhivya B Sridevi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2019年第2期229-252,共24页
Similarity measure is an essential tool to compare and determine the degree of similarity between intuitionistic fuzzy sets (IFSs). In this paper, a new similarity measure between intuitionistic fuzzy sets based on th... Similarity measure is an essential tool to compare and determine the degree of similarity between intuitionistic fuzzy sets (IFSs). In this paper, a new similarity measure between intuitionistic fuzzy sets based on the mid points of transformed triangular fuzzy numbers is proposed. The proposed similarity measure provides reasonable results not only for the sets available in the literature but also gives very reasonable results, especially for fuzzy sets as well as for most intuitionistic fuzzy sets. To provide supportive evidence, the proposed similarity measure is tested on certain sets available in literature and is also applied to pattern recognition and medical diagnosis problems. It is observed that the proposed similarity measure provides a very intuitive quantification. 展开更多
关键词 FUZZY SETS (FSs) Intuitionistic FUZZY SETS (IFSs) Most intuitionistic FUZZY SETS (MIFSs) Simi- larity measure (sm) Transformed TRIANGULAR FUZZY NUMBERS (TTFNs)
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Separation of Neighboring REElementsfrom Sm_2O_3Eu_2O_3Gd_2O_3 System by a Stepwise ChlorinationChemical Vapor Transport Reaction 被引量:1
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作者 孙艳辉 王之昌 郭雷 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第3期178-181,共4页
The mutual separation characteristics were investigated for the neighboring Sm, Eu and Gd from their ternary oxide mixture Sm 2O 3 Eu 2O 3 Gd 2O 3 by a stepwise chlorination chemical vapor transport reaction ... The mutual separation characteristics were investigated for the neighboring Sm, Eu and Gd from their ternary oxide mixture Sm 2O 3 Eu 2O 3 Gd 2O 3 by a stepwise chlorination chemical vapor transport reaction within 6 h using AlCl 3 as complex former. The rare earth chlorides were more readily transported and concentrated in the middle temperature range of 980~1100 K and the transport efficiency was in the order of Sm≈Gd>Eu. The separation factor, expressed as molar ratio for the resulting chlorides, was 1 70 for Eu∶Sm, 1 88 for Eu∶Gd, 1 24 for Sm∶Gd in the higher temperature region, and 2 76 for Sm∶Eu, 2 83 for Gd∶Eu and 1 12 for Gd∶Sm in the lower temperature region, respectively. All results are much higher than those of the conventional wet process. 展开更多
关键词 Rare earths Chemical vapor transport Rare earth separation sm 2O 3 Eu 2O 3 Gd 2O 3 system
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Modeling and monitoring of nonlinear multi-mode processes based on similarity measure-KPCA 被引量:9
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作者 王小刚 黄立伟 张颖伟 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第3期665-674,共10页
A new modeling and monitoring approach for multi-mode processes is proposed.The method of similarity measure(SM) and kernel principal component analysis(KPCA) are integrated to construct SM-KPCA monitoring scheme,wher... A new modeling and monitoring approach for multi-mode processes is proposed.The method of similarity measure(SM) and kernel principal component analysis(KPCA) are integrated to construct SM-KPCA monitoring scheme,where SM method serves as the separation of common subspace and specific subspace.Compared with the traditional methods,the main contributions of this work are:1) SM consisted of two measures of distance and angle to accommodate process characters.The different monitoring effect involves putting on the different weight,which would simplify the monitoring model structure and enhance its reliability and robustness.2) The proposed method can be used to find faults by the common space and judge which mode the fault belongs to by the specific subspace.Results of algorithm analysis and fault detection experiments indicate the validity and practicability of the presented method. 展开更多
关键词 监控方法 过程建模 KPCA 多模式 相似度量 非线性 核主成分分析 判断故障
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Application of Electrical Capacitance Tomography to the Concentration Measurement in a Cyclone Dipleg 被引量:5
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作者 孙猛 刘石 +1 位作者 李志宏 雷兢 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第4期635-639,共5页
精确稳固的集中测量在过程工业起一个关键作用。脱机分析的大小能被用来估计过程效率,以在流动识别问题,并且验证计算模型。联机大小能被用于活跃控制。电的电容断层摄影术(ECT ) 是有在多相的流动测量的大潜力的一种唯一的测量技术... 精确稳固的集中测量在过程工业起一个关键作用。脱机分析的大小能被用来估计过程效率,以在流动识别问题,并且验证计算模型。联机大小能被用于活跃控制。电的电容断层摄影术(ECT ) 是有在多相的流动测量的大潜力的一种唯一的测量技术。试验性的研究在气旋隔板 dipleg 在稳固的集中大小上被执行,用 ECT。在这个实验,八个电极为被放在 dipleg 的直试管上的 ECT 传感器被选择。根据螺丝钉, feeder 和气流的效果从气旋的顶评估的波动的特征被分析。方法的可行性和可靠性被试验性的结果验证。 展开更多
关键词 电容层析成像技术 分离器 料腿 浓度测量
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Orthogonality of inductosyn angle-measuring system error and error-separating technology 被引量:1
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作者 任顺清 曾庆双 王常虹 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第4期376-379,共4页
Round inductosyn is widely used in inertial navigation test equipment, and its accuracy has significant effect on the general accuracy of the equipment. Four main errors of round inductosyn,i.e. the first-order long-p... Round inductosyn is widely used in inertial navigation test equipment, and its accuracy has significant effect on the general accuracy of the equipment. Four main errors of round inductosyn,i.e. the first-order long-period (360°) harmonic error, the second-order long-period harmonic error, the first-order short-period harmonic error and the second-order short-period harmonic error, are described, and the orthogonality of these four kinds of errors is studied. An error separating technology is proposed to separate these four kinds of errors, and in the process of separating the short-period harmonic errors, the arrangement in the order of decimal part of the angle pitch number can be omitted. The effectiveness of the technology proposed is proved through measuring and adjusting the angular errors. 展开更多
关键词 正交性 感应式传感器 角测量系统 错误分离技术
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Mathematical Simulation of Nd and Sm Extract Separation in (Nd,Sm)Cl_3-HCL-HEHEHP-Kerosene System
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作者 黄文梅 应娓娟 王乃宾 《Rare Metals》 SCIE EI CAS CSCD 1995年第1期1-7,共7页
A number of epuilibrium data of single stage in the system (Nd-SM)Cl_3-HCl-H_2O-1mol/L HEHEHP-kerosence was determined On the basis of epuilibrium data, two mathematical describing extract epui-librium of Nd and Sm... A number of epuilibrium data of single stage in the system (Nd-SM)Cl_3-HCl-H_2O-1mol/L HEHEHP-kerosence was determined On the basis of epuilibrium data, two mathematical describing extract epui-librium of Nd and Sm were developed.The models cover wide available ranges (the total RE concentration inepuilibrated apueous phase is 0. 07~0. 77 mol/L and the acidity is 0. 11~0. 48 mol/L; the mole fraction ofMd or Sm is 0. 020~0. 998) with small average relative errors(The model of Nd is 6. 11 % and the model ofSm is 3. 07 %, respectively ) With the developed models, the extract behaviors of Nd and sM, such as thedistribution of rare earth concentrations in both phase, the effects of acidity, RE concentration, mole fractionof RE in aqueous phase on the RE concentration in organic phase, were researched The separation circuits be-tween Nd and Sm simulated and performed by the experiments in laboratory. The purities obtained prod-uct of Nd_2O_3O_3 as well as Sm_2O_3 were higher than 99%.Two calculation programs were written in BASIC language. One of them is used for publishing epuilibri-um model and another is used for simulation of fractional solvent extraction. The amulation results obtainedmay serve as a reference for designing solvent extraction process. 展开更多
关键词 Mathematical simulation Extract separation of Nd and sm
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Separability criteria based on a class of symmetric measurements
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作者 Lemin Lai Shunlong Luo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第6期51-58,共8页
Highly symmetric quantum measurements,such as mutually unbiased measurements(MUMs)and general symmetric informationally complete positive-operator-valued measures(GSICPOVMs),play an important role in both foundational... Highly symmetric quantum measurements,such as mutually unbiased measurements(MUMs)and general symmetric informationally complete positive-operator-valued measures(GSICPOVMs),play an important role in both foundational and practical aspects of quantum information theory.Recently,a broad class of symmetric measurements were introduced[K Siudzińska,(2022)Phys.Rev.A 105,042209],which can be viewed as a common generalization of MUMs and GSIC-POVMs.In this work,the role of these symmetric measurements in entanglement detection is studied.More specifically,based on the correlation matrices defined via(informationally complete)symmetric measurements,a separability criterion for arbitrary dimensional bipartite systems is proposed.It is shown that the criterion is stronger than the method provided by Siudzińska,meanwhile,it can unify several popular separability criteria based on MUMs or GSIC-POVMs.Furthermore,using these(informationally complete)symmetric measurements,two efficient criteria are presented to detect the entanglement of tripartite quantum states.The detection power and advantages of these criteria are illustrated through several examples. 展开更多
关键词 entanglement detection separability criterion symmetric measurement correlation matrix
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Fault Diagnosis and Separation for a Distributed Rotary-laser Scanning System
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作者 Siyang GUO Yin GUO +2 位作者 Shibin YIN Hongbo XIE Jigui ZHU 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第4期70-78,共9页
The wMPS is a laser-based measurement system used for large scale metrology.However,it is susceptible to external factors such as vibrations,which can lead to unreliable measurements.This paper presents a fault diagno... The wMPS is a laser-based measurement system used for large scale metrology.However,it is susceptible to external factors such as vibrations,which can lead to unreliable measurements.This paper presents a fault diagnosis and separation method which can counter this problem.To begin with,the paper uses simple models to explain the fault diagnosis and separation methods.These methods are then mathematically derived using statistical analysis and the principles of the wMPS.A comprehensive solution for fault diagnosis and separation is proposed,considering the characteristics of the wMPS.The effectiveness of this solution is verified through experimental observations.It can be concluded that this approach can detect and separate false observations,thereby enhancing the reliability of the wMPS. 展开更多
关键词 rotary-laser scanning measurement system least square method fault diagnosis fault separation
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压力敏感涂料测量技术在掠型叶栅表面测压中的应用
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作者 高丽敏 雷祥福 +3 位作者 杨冠华 孙大坤 常龙睿 高天宇 《推进技术》 EI CAS CSCD 北大核心 2024年第4期210-221,共12页
为了获得某掠型叶片吸力面压力分布,对一稠度为1.53,掠角为10.7°的掠叶栅进行了光路布局以及压力敏感涂料(PSP)压力测量,利用图像处理和三维重构算法得到了可读性高、便于数据提取的三维叶片吸力面压力分布,并和测压孔测量结果进... 为了获得某掠型叶片吸力面压力分布,对一稠度为1.53,掠角为10.7°的掠叶栅进行了光路布局以及压力敏感涂料(PSP)压力测量,利用图像处理和三维重构算法得到了可读性高、便于数据提取的三维叶片吸力面压力分布,并和测压孔测量结果进行了对比。结果表明:利用自主发展的光路布局方法,有效解决了叶片表面光照辐照度不均匀、拍摄视角受限的问题;得到了高信噪比的原始压敏图像以及宽范围多工况的掠叶栅吸力面全域压力分布。与测压孔测量相比,PSP测量误差在5%以内,并且PSP测量结果还捕捉到了峰值等熵马赫数位置沿弦向的迁移以及叶片尾缘的气流分离现象。对不同攻角和来流马赫数下的掠型叶片吸力面压力分布进行分析:掠型叶片在零攻角和正攻角下存在明显的径向压力梯度,促使后掠型叶片气流向前掠迁移,增加了前掠下流低能流体的能量,使得前掠更有利于延迟角区分离,后掠则更容易发生角区分离;掠型叶片在低来流马赫数下展向压力对称性良好,掠设计的影响不显著,高来流马赫数则放大了前后掠对角区分离控制效果的不同。相比传统测压孔有限的压力分辨率,PSP测量可为掠型叶片设计和流动机理分析提供丰富可靠的压力实验数据。 展开更多
关键词 压力敏感涂料 光路布局 掠型叶片 压力测量 角区分离 掠角
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基于多频涡流技术的燃料棒包壳管氧化膜厚度测量方法
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作者 周国正 陶钰 +3 位作者 张娜 梁军 许小兵 叶朝锋 《无损检测》 CAS 2024年第5期62-68,共7页
核燃料棒包壳管表面的氧化膜会影响其导热性能,使燃料棒的温度上升,加快燃料包壳的腐蚀速度,给反应堆带来潜在安全风险。故有必要对氧化膜厚度进行精确测量。为此,构建了燃料棒包壳管的三维有限元仿真模型,对燃料包壳多频检测进行了分析... 核燃料棒包壳管表面的氧化膜会影响其导热性能,使燃料棒的温度上升,加快燃料包壳的腐蚀速度,给反应堆带来潜在安全风险。故有必要对氧化膜厚度进行精确测量。为此,构建了燃料棒包壳管的三维有限元仿真模型,对燃料包壳多频检测进行了分析,总结了激励频率、包壳管电导率和金属涂层厚度对氧化膜测量结果的影响规律;提出了融合多频测量数据,抑制干扰因素影响,精确计算氧化膜厚度的方法,并进行了试验验证。结果表明,该方法的氧化膜厚度计算误差小于1μm,可用于燃料包壳管氧化膜厚度的量化表征。 展开更多
关键词 包壳管氧化膜 涡流检测 有限元仿真 多频测量 参数分离
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基于GSM通信技术的无线测控系统设计 被引量:11
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作者 邢建春 方虎生 +2 位作者 王平 刘广 文江 《计算机测量与控制》 CSCD 2004年第4期345-348,共4页
传统的使用类似于数传电台的无线通信设备为通信手段的计算机无线测量与控制系统,建设和维护费用高,不能满足工程上大地理范围的测量与控制要求。通过对GSM通信系统的研究,将GSM移动通信终端模块嵌入到测控系统中,设计出相应的软硬件和... 传统的使用类似于数传电台的无线通信设备为通信手段的计算机无线测量与控制系统,建设和维护费用高,不能满足工程上大地理范围的测量与控制要求。通过对GSM通信系统的研究,将GSM移动通信终端模块嵌入到测控系统中,设计出相应的软硬件和测控模块,实现了利用GSM通信网络完成计算机测控系统的无线测量与控制。工程实践表明基于GSM通信网络的无线测控系统,非常适合大范围的无线测控应用场合,同时系统还具有通用性好、地理覆盖面广、免调试维护、低廉的建设与运营费和控制方式灵活等优点。 展开更多
关键词 无线测控系统 系统设计 Gsm通信 无线通信设备 计算机 无线测量 移动通信
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玄武岩分相Sm-Nd内部等时线定年方法流程 被引量:5
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作者 张利国 段桂玲 +5 位作者 杨红梅 杨梅 谭娟娟 段瑞春 邱啸飞 刘重芃 《岩矿测试》 CAS CSCD 北大核心 2014年第5期640-648,共9页
长期以来,对玄武岩精确测年一直是困扰地质学家的重大科学问题。玄武岩结构和组成特殊,岩石中矿物组成单一、锆石十分稀少,颗粒很细,采用物理方法挑选单矿物和锆石十分困难,很难应用内部等时线法和锆石U-Pb法研究其成岩时代。而全... 长期以来,对玄武岩精确测年一直是困扰地质学家的重大科学问题。玄武岩结构和组成特殊,岩石中矿物组成单一、锆石十分稀少,颗粒很细,采用物理方法挑选单矿物和锆石十分困难,很难应用内部等时线法和锆石U-Pb法研究其成岩时代。而全岩样品间因岩浆分异产生的147Sm/144Nd比值差别很小,等时线年龄相对误差较大;Rb含量很低,Rb/Sr比值很小,全岩Sm-Nd法、Rb-Sr法常常不能给出正确可信的年龄。根据内部等时线法原理,本文通过化学方法,采用王水和氢氟酸-硝酸对玄武岩样品进行分步溶解,分别对同一件样品的王水溶解相、王水不溶相和全岩开展Sm-Nd同位素组成分析。结果表明:通过不同酸介质分步溶解,可提取玄武岩中石英、透辉石、长石等矿物组合,该组合与其全岩具有相同的εNd(t)和一致的Nd同位素模式年龄;矿物与全岩构筑的内部等时线中,147Sm/144Nd比值的变化由全岩之间的0.005扩大到0.11,143Nd/144Nd值的变化由全岩的0.512500~0.512547扩大到0.512500~0.513145。通过该方法获得了与已有锆石U-Pb年龄在误差范围内一致的Sm-Nd等时线年龄:t=(99121) Ma(MSWD=2.1)。通过对比研究,本文认为:玄武岩分相Sm-Nd内部等时线定年方法,适用于前寒武纪及更古老的玄武岩样品的年龄测定。该方法的建立不仅有效提高玄武岩Sm-Nd等时线定年成功率,也为其他隐晶质且不易挑出单矿物样品的年龄测定提供了新的思路。 展开更多
关键词 玄武岩 分步溶样 分相 sm-ND同位素 年代学 矿物内部等时线
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同一岩石试样的Lu-Hf和Sm-Nd快速分离及国家岩石标准物质的Hf-Nd同位素比值精确测定 被引量:7
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作者 李献华 刘颖 +3 位作者 杨岳衡 陈福坤 涂湘林 祁昌实 《岩石学报》 SCIE EI CAS CSCD 北大核心 2007年第2期221-226,共6页
本文报道基于Li_2B_4O_7熔融样品、采用AG50W-X8和HDEHP组合或RE和HDEHP组合色谱交换柱,对同一岩石试样快速分离Sm-Nd-Lu-Hf的方法。用这两种方法对国际岩石标准BHVO-2、GSP-2和JB-1进行了Lu-Hf、Sm-Nd分离和^(143) Nd/^(144)Nd、^(176)... 本文报道基于Li_2B_4O_7熔融样品、采用AG50W-X8和HDEHP组合或RE和HDEHP组合色谱交换柱,对同一岩石试样快速分离Sm-Nd-Lu-Hf的方法。用这两种方法对国际岩石标准BHVO-2、GSP-2和JB-1进行了Lu-Hf、Sm-Nd分离和^(143) Nd/^(144)Nd、^(176)Hf/^(177)Hf测定,并测定了BHVO-2、JB-1和JB-3的Lu/Hf和Sm/Nd比值,获得的结果在误差范围内与这些样品的参考值一致。同时,我们对国家岩石标准物质GBW07109、GBW07110和GBW07113进行了多次平行分析,首次获得了这些岩石标准的Nd-Hf同位素结果。 展开更多
关键词 Lu-Hf-sm-Nd化学分离 Nd-Hf同位素比值 岩石标样
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