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Non-Kramers doublet ground state in a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) investigated by ultrasonic measurements
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作者 张化远 Kazuhei Wakiya +2 位作者 Mitsuteru Nakamura Masahito Yoshizawa Yoshiki Nakanish 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期405-411,共7页
We performed ultrasonic measurements on a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) to explore the ground state properties derived from non-Kramers Γ_(3) doublet of Pr^(3+).PrRu_(2)In_(2)Zn_(18) is a quaternary... We performed ultrasonic measurements on a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) to explore the ground state properties derived from non-Kramers Γ_(3) doublet of Pr^(3+).PrRu_(2)In_(2)Zn_(18) is a quaternary derivative of the ternary compound PrRu_(2)Zn_(20) that exhibits a structural phase transition at T_S=138 K.In PrRu_(2)In_(2)Zn_(18),the Zn atoms at the 16c site in PrRu_(2)Zn_(20) are selectively replaced by In atoms.A monotonic increase was observed in the temperature dependence of elastic constants C_L=(C_(11)+2C_(12)+4C_(44))/3 and C_(T)=(C_(11)-C_(12)+C_(44))/3 in the temperature range around T_(S) to which an elastic softening was observed in(C_(11)-C_(12))/2 for PrRu_(2)Zn_(20).The disappearance of the softening indicates that the structural transition in PrRu_(2)Zn_(20) is suppressed by the substitution of Zn ions by In ones with a larger ionic radius.Alternatively,the C_(T) of PrRu_(2)In_(2)Zn_(18) exhibits a precursor Curie-type elastic softening toward low temperatures being responsible for the non-Kramers Γ_(3) ground state.We discuss the ground state and the evolution of the elastic properties of the different single-crystal samples of PrRu_(2)In_(2)Zn_(18) grown under different conditions. 展开更多
关键词 ultrasonic measurements non-Kramers doublet structural phase transition crystalline electric field effect
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Electric field intensity measurement by using doublet electromagnetically induced transparency of cold Rb Rydberg atoms
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作者 宫廷 师帅 +7 位作者 姬中华 郭古青 孙小聪 田亚莉 邱选兵 李传亮 赵延霆 贾锁堂 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期405-409,共5页
We demonstrate a simple method to measure electric field intensity by using doublet electromagnetically induced transparency(EIT) spectra of cold Rb Rydberg atoms, where the frequency of the coupling laser does not ne... We demonstrate a simple method to measure electric field intensity by using doublet electromagnetically induced transparency(EIT) spectra of cold Rb Rydberg atoms, where the frequency of the coupling laser does not need to be locked. Based on the Stark splitting of the Rb Rydberg state, 10D_(3/2), under electric fields and the corresponding calculated polarizabilities, the real electric field intensity is calculated using the difference in radio-frequency diffraction between two acousto-optic modulators, which acts as a frequency criterion that allows us to measure the electrical field without locking the coupling laser. The value measured by this simple method shows a good agreement with our previous work [Opt.Express 29 1558(2021)] where the frequency of the coupling laser needs to be locked with an additional EIT spectrum based on atom vapor and a proportional–integral–differential feedback circuit. Our presented method can also be extended to the measurement of electric field based on hot Rydberg atom vapor, which has application in industry. 展开更多
关键词 doublet electromagnetically induced transparency(EIT) Aulter–Townes(AT)splitting Rydberg atom electric field measurement
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NON-CONTACT MEASUREMENT SYSTEM OF FREEFORM SURFACE AND NURBS RECONSTRUCTION OF MEASUREMENT POINTS 被引量:4
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作者 Li Jian Wang Wen Chen Zichen Institute of Advanced Manufacturing Engineering, Zhejiang University, Hangzhou 310027, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第4期366-371,共6页
Based on the development of the non-contact measurement system of free-formsurface, NURBS reconstruction of measurement points of freeform surface is effectively realized bymodifying the objective function and recursi... Based on the development of the non-contact measurement system of free-formsurface, NURBS reconstruction of measurement points of freeform surface is effectively realized bymodifying the objective function and recursive procedure and calculating the optimum number ofcontrol points. The reconstruction precision is evaluated through Ja-cobi's transformation method.The feasibility of the measurement system and effectiveness of the reconstruction algorithm aboveare proved by experiment. 展开更多
关键词 freeform surface non-contact measurement NURBS precision evaluation
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Void Fraction Measurement in Oil-Gas Transportation Pipeline Using an Improved Electrical Capacitance Tomography System 被引量:5
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作者 牛刚 贾志海 王经 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第4期476-481,共6页
To measure the void fraction online in oil-gas pipeline, an improved electrical capacitance tomography (ECT) system has been designed. The capacitance sensor with new structure has twelve internal electrodes and overc... To measure the void fraction online in oil-gas pipeline, an improved electrical capacitance tomography (ECT) system has been designed. The capacitance sensor with new structure has twelve internal electrodes and overcomes the influence of the pipe wall. The data collection system is improved by using high performance IC (integrated circuit). Static tests of bubble flow, stratified flow and annular flow regime are carried out. Measurements are taken on bubble flow, stratified flow and slug flow. Results show that the new ECT system performs well on void fraction measurement of bubble flow and stratified flow, but the error of measurement for slug flow is more than 10%. 展开更多
关键词 electrical capacitance tomography void fraction measurement oil-gas transportation
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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
Accurate solid concentration measurement plays a key role in the process industry. Measurements analyzed offline can be used to estimate process efficiencies, to identify problems in a flow, and to validate computatio... Accurate solid concentration measurement plays a key role in the process industry. Measurements analyzed offline can be used to estimate process efficiencies, to identify problems in a flow, and to validate computational models. Online measurements can be used for active control. Electrical capacitance tomography (ECT) is a unique measuring technique with great potential in multiphase flow measurement. Experimental studies are carried out on a solid concentration measurement in a cyclone separator dipleg, using ECT. In this experiment eight electrodes are selected for the ECT sensor that is placed on the straight tube of the dipleg. The fluctuating characteristics according to the screw feeder and the effect of the airflow rate from the top of the cyclone are analyzed. The feasibility andreliability of the method are verified by the experimental results. 展开更多
关键词 electrical capacitance tomography concentration measurement cyclone separator dipleg gas-solid two-phase flow
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Detecting Impact Damage in Carbon Fabric/epoxy-matrix Composites by Ultrasonic F-scan and Electrical Resistance Measurement 被引量:3
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作者 谢小林 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第2期214-217,共4页
The status and the variation of electrical resistance of impacted carbon fiber/epoxy-matrix composites were studied by ultrasonic F-scan and electrical resistance measurement The experimental results shows that impact... The status and the variation of electrical resistance of impacted carbon fiber/epoxy-matrix composites were studied by ultrasonic F-scan and electrical resistance measurement The experimental results shows that impact damage energy threshold value of carbon fabric/epoxy-matrix composites can determine by using ultrasonic F-scan. When the impact energy exceeds the threshold value, damage is generated in composites. Electrical resistance of impacted composites is changed owing to the contact of each carbon fiber unit in composites, which cause a change of the series-parallel in conductors. The veracity of detecting impact damage in composites can be improved in this case. 展开更多
关键词 carbon fabric/epoxy-matrix composites impact damage ultrasonic F-scan electrical resistance measurement
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The electrical parameters measurement system for electrotome output based on Labview 被引量:3
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作者 Shengjie Yan Yu Zhou +3 位作者 Bowen Yan Dianli Li Chengli Song Zhaohua Chang 《Journal of Biomedical Science and Engineering》 2013年第6期661-668,共8页
An accurate detection of the effective values of electric voltage and current from high frequency power generators is a precondition for the development of smart electrotomes. In this light, an energy detection system... An accurate detection of the effective values of electric voltage and current from high frequency power generators is a precondition for the development of smart electrotomes. In this light, an energy detection system based on personal computer (PC) is developed hereby. It senses voltage and current in isolation from generators with transformers, and then the measured values are amplified, filtered, transformed into single-ended signals and converted to RMS. The detected signals are transformed into digital signals through Data Acquisition Card (DAQ) and the data are processed with quadratic fit in Labview. Finally, the controller completes constant power output. The experiment results indicate that the energy detection system can measure the output parameters precisely and the controller can achieve constant power control. 展开更多
关键词 : Energy GENERATOR HIGH-FREQUENCY electrical PARAMETERS measurement CONSTANT Power
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Analysis and Applications of the Measurement Uncertainty in Electrical Testing 被引量:2
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作者 Hung-Lu Wang 《Journal of Power and Energy Engineering》 2015年第4期297-305,共9页
Recently, uncertainty measurement is more and more recognizable in modern data management, conformity assessment, and laboratory accreditation system because of its importance. In this paper, a set of reasonable proba... Recently, uncertainty measurement is more and more recognizable in modern data management, conformity assessment, and laboratory accreditation system because of its importance. In this paper, a set of reasonable probability explanations are introduced and an effective method is pro- posed to quantify the assessment indices for the uncertainty measurement of electrical testing laboratory. First of all, the influence from uncertainty factors during the test process is taken into account. With the use of ISO/IEC Guide 98-3 standard and probability theory, the index and model for the measurement uncertainty assessment of a laboratory is then derived. From the simulation results of safety testing, laboratory uncertainty measurement assessment activity for actual electrical appliances, and the confirmation of Monte Carlo simulation method, the appropriateness and correctness of proposed method are verified. 展开更多
关键词 electrICAL TESTING measurement UNCERTAINTY TESTING LABORATORY
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Revamping design of an EAF automatic temperature measurement and sampling robot
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作者 JIN Guoping WEI Zhenhong DONG Yiming 《Baosteel Technical Research》 CAS 2023年第3期32-39,共8页
The function,features,and architecture of a robot that performs automatic temperature measurement and sampling applied on a 150-t AC electric arc furnace(EAF)production line of Baosteel were presented,and the key poin... The function,features,and architecture of a robot that performs automatic temperature measurement and sampling applied on a 150-t AC electric arc furnace(EAF)production line of Baosteel were presented,and the key points of design and revamping experience on the site layout,device protection,lance tool,probe container,measuring position control,and system safety were summarized.Furthermore,a valuable reference for the application of automatic temperature measuring and sampling robots in EAF steelmaking plants will be provided. 展开更多
关键词 ROBOT electric arc furnace(EAF) temperature measuring sampling
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ELECTRIC RESISTANCE MEASUREMENT OF CARBON FIBRE SMART CONCRETE 被引量:1
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作者 赵斌元 李卓球 吴代华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1995年第4期52-56,共5页
After having measured the electric resistance of carbon firbre reinforced concrete (CFRC) by applying a D. C. current, it was found that the current passing through the specimen under a constant voltage decreased with... After having measured the electric resistance of carbon firbre reinforced concrete (CFRC) by applying a D. C. current, it was found that the current passing through the specimen under a constant voltage decreased with the time, and if changing the value of voltage, the electric resistance was obviously affected. When current flew through the specimen, polarisation emerged under a high votage (>5 upsilon), but that could be neglected under a low voltage (<5 upsilon).(1) 展开更多
关键词 carbon fibre smart concrete electric resistance measurement
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Facing a Problem of Electrical Energy Quality in Ship Networks-measurements, Estimation, Control 被引量:2
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作者 TomaszTarasiuk JanuszMindykowski XiaoyanXu 《上海海运学院学报》 北大核心 2003年第3期193-199,共7页
In this paper, electrical energy quality and its indices in ship electric networks are introduced, especially the meaning of electrical energy quality terms in voltage and active and reactive power distribution indice... In this paper, electrical energy quality and its indices in ship electric networks are introduced, especially the meaning of electrical energy quality terms in voltage and active and reactive power distribution indices. Then methods of measurement of marine electrical energy indices are introduced in details and a microprocessor measurement-diagnosis system with the function of measurement and control is designed. Afterwards, estimation and control of electrical power quality of marine electrical power networks are introduced. And finally, according to the existing method of measurement and control of electrical power quality in ship power networks, the improvement of relative method is proposed. 展开更多
关键词 船舶 电子网络 电能质量 测量 估计 控制 电气设备
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Non-contact measurement and multi-objective analysis of drilling temperature when drilling B_4C reinforced aluminum composites
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作者 A.TASKESEN K.KUTUKDE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第1期271-283,共13页
Non-contact measurements of machining temperatures were performed with optical pyrometer when drilling particle(B4C) reinforced metal matrix composites(MMCs) with different drills. The effect of particle content, ... Non-contact measurements of machining temperatures were performed with optical pyrometer when drilling particle(B4C) reinforced metal matrix composites(MMCs) with different drills. The effect of particle content, cutting speed, feed rate and tool material on the maximum drilling temperature was investigated. The drilling parameters were optimized based on multiple performance characteristics in terms of the maximum cutting temperature and tool wear. According to the results, the most influential control factors on the cutting temperatures are found to be particle fraction, feed rate and interaction between the cutting speed and particle content, respectively. The influences of the cutting speed and drill material on the drilling temperature are found to be relatively lower for the used range of parameters. Minimum cutting temperatures are obtained with lower particle fraction and cutting speed, with relatively higher feed rates and carbide tools. The results reveal that optimal combination of the drilling parameters can be used to obtain both minimum cutting temperature and tool wear. 展开更多
关键词 metal matrix composite drilling temperature WEAR non-contact measurement grey relation
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On-line measurement of electrical variables of the transducer during ultrasonic welding and cutting
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作者 闫久春 刘井权 杨士勤 《China Welding》 EI CAS 2002年第2期133-137,共5页
A measurement system for high power electrical variables with ultrasonic frequency was established. It can measure the effective values of the voltage and the current, the active power, the phase difference of voltage... A measurement system for high power electrical variables with ultrasonic frequency was established. It can measure the effective values of the voltage and the current, the active power, the phase difference of voltage and current, the frequency of the transducer during ultrasonic welding and cutting. In sampling circuits of the system, the measured current is sensed by using a no capacitance and no inductance precision resistor and is treated with a difference amplifier, the measured voltage is processed by using a proportional amplifier. For achieving good amplitude frequency characteristics and rapid measurement of high frequency signals, the resistors, capacitors and amplifiers used in the system are rationally selected. Calibrating experiments show that relative errors are less than 1% for voltage and current effective values and less than 2.5% for active power, and absolute errors are ±1 Hz for frequency and ±1.7° for phase difference of voltage and current in the range of 17~23 kHz . 展开更多
关键词 ultrasonic welding ultrasonic cutting on line measurement electrical variables
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Evaluation of Impact Damage Tolerance in Carbon Fabric/epoxy-matrix Composites by Electrical Resistance Measurement
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作者 李志鹏 谢小林 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第3期484-488,共5页
Impact damage tolerance is provided in intensity design on composites. The compression intensity of impacted composites requires more than 60% of its original intensity. The influence of impact on compressive intensit... Impact damage tolerance is provided in intensity design on composites. The compression intensity of impacted composites requires more than 60% of its original intensity. The influence of impact on compressive intensity and electrical resistance of carbon fabric/epoxy-matrix composites was studied in this paper. The experimental results shows that impact can cause damage in composites, degenerate compressive intensity, and increase resistance. The electrical resistance change rate was used as an evaluation indicator of impact damage tolerance of composites. Impact damage, which results from the applying process of composites, can be identified in time by electrical resistance measurement. So, the safety performance of composites can also be improved. 展开更多
关键词 carbon fabric/epoxy-matrix composites impact damage tolerance compressive intensity after impacted electrical resistance measurement
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Electrical measurement on individual multi-walled carbon nanotubes 被引量:1
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作者 邹小平 H.ABE +4 位作者 T.SHIMIZU A.ANDO H.OKUMOTO 朱申敏 周豪慎 《中国有色金属学会会刊:英文版》 CSCD 2006年第B02期772-775,共4页
The characterization of electrical property of multi-walled carbon nanotubes (MWCNTs) on a nanometer scale is essential for their potential application in nano-electronic devices. The MWCNTs were synthesized on Fe2O3/... The characterization of electrical property of multi-walled carbon nanotubes (MWCNTs) on a nanometer scale is essential for their potential application in nano-electronic devices. The MWCNTs were synthesized on Fe2O3/SiO2/Si substrate and Pt plate substrate by simple thermal chemical vapor deposition (STCVD) technique and the electrical measurements of individual MWCNT grown on silicon substrate and Pt plate substrate were performed by home-made 'nano-manipulator', respectively. According to current-voltage curves obtained in the experiments the current density that the MWCNTs can carry is calculated to be about 107 A/cm2, which is much larger than that of normal metals. 展开更多
关键词 多壁碳纳米管 电学测量 简易热化学汽相沉积 合成
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Illumination and Voltage Dependence of Electrical Characteristics of Au/0.03 Graphene-Doped PVA/n-Si Structures via Capacitance/Conductance-Voltage Measurements
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作者 SAHAR Alialy AHMET Kaya +1 位作者 I Uslua EMSETTIN Altmdal 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第11期92-96,共5页
Au/n-Si (MS) structures with a high dielectric interlayer (0.03 graphene-doped PVA) are fabricated to investigate the illumination and voltage effects on electrical and dielectric properties by using capacitance-v... Au/n-Si (MS) structures with a high dielectric interlayer (0.03 graphene-doped PVA) are fabricated to investigate the illumination and voltage effects on electrical and dielectric properties by using capacitance-voltage (C-V) and conductance-voltage (G/w-V) measurements at room temperature and at 1 MHz. Some of the main electrical parameters such as concentration of doping atoms (ND), barrier height ( ФB( C - V) ), depletion layer width (WD) and series resistance (Rs) show fairly large illumination dispersion. The voltage-dependent profile of surface states (Nss) and resistance of the structure (Ri ) are also obtained by using the dark-illumination capacitance (Cdark- Cm) and Nicollian-Brews methods, respectively, For a clear observation of changes in electrical parameters with illumination, the values of ND, WD, ФB(O- V) and Rs are drawn as a function of illumination intensity. The values of ND and WD change almost linearly with illumination intensity. On the other hand, Rs decreases almost exponentially with increasing illumination intensity whereas ФB(C - V) increases. The experimental results suggest that the use of a high dielectric interlayer (0.03 graphene-doped PVA) considerably passivates or reduces the magnitude of the surface states. The large change or dispersion in main electrical parameters can be attributed to generation of electron-hole pairs in the junction under illumination and to a good light absorption. All of these experimental results confirm that the fabricated Au/0.03 graphene-doped PVA/n-Si structure can be used as a photodiode or a capacitor in optoelectronic applications. 展开更多
关键词 SI PVA Illumination and Voltage Dependence of electrical Characteristics of Au/0.03 Graphene-Doped PVA/n-Si Structures via Capacitance/Conductance-Voltage measurements
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Machine Vision for Non-Contact Automated Countersink Measurement
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作者 LIANG Ying WU Xiaowei +3 位作者 JIA Chunning YU Long YE Shunjian LE Bin 《Aerospace China》 2022年第3期32-37,共6页
The slug rivet is widely used in wing assembly due to its longer fatigue life and better sealing performance compared with other connection technologies.As a countersink with dual-angle is widely adopted for this type... The slug rivet is widely used in wing assembly due to its longer fatigue life and better sealing performance compared with other connection technologies.As a countersink with dual-angle is widely adopted for this type of connection,the countersink diameter and depth are key factors that affect assembly quality.Therefore,it is of great importance to efficiently inspect the countersink quality to ensure high accuracy.However,contact measurements are susceptible to the loss of accuracy due to cutting debris and lube build-up,while the hole-scanning method using laser profilometry is time consuming and complex.In this paper,a non-contact method for countersink diameter and depth measurement based on a machine vision system is proposed.The countersink diameter can be directly measured by the machine vision system,while the countersink depth is determined through the countersink diameter indirectly.First,by means of image processing technology together with an improved edge detection algorithm,the countersink diameter can be obtained.Then,a 3D microscope is employed to measure the countersink depth,which helps to model the countersink.As a result,once the countersink diameter is measured,so is the depth.The experimentation demonstrated that this method has strong feasibility and enables time saving,which is conducive to improve the riveting efficiency. 展开更多
关键词 machine vision non-contact measurement countersink
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Calculation of Constitutive Parameters from Electric and Magnetic Field Measurements in an Anisotropic Medium with a Triaxial Instrument
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作者 Ertan Peksen 《International Journal of Geosciences》 2013年第1期58-68,共11页
A hypothetical electric and magnetic induction tensor is considered in an anisotropic medium. The sources are magnetic dipoles. In such a medium, constitute parameters can be calculated by combining electric and magne... A hypothetical electric and magnetic induction tensor is considered in an anisotropic medium. The sources are magnetic dipoles. In such a medium, constitute parameters can be calculated by combining electric and magnetic field measurements. Constitutive parameters are not a scalar in this case. They are tensors, so parameters have at least both horizontal and vertical components in a uniaxial medium. These calculated parameters from the field measurement are horizontal and vertical conductivity, permittivity, and magnetic permeability. Operating frequency range is also quite large. It is up to 4 GHz. A hypothetical instrument should measure gradient fields both electric and magnetic types as well. 展开更多
关键词 electrical Anisotropy Triaxial measurement electric and Magnetic Dipoles Induction Well Logging
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Partial Discharge Measurement of OCP-Tapes in Rotating Electrical Machines
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作者 Philipp Pretis Jurgen Fabian +4 位作者 Christof Sumereder Michael Muhr Helmut Heinle Christoph Richter Bernhard Brandstatter 《Journal of Energy and Power Engineering》 2014年第8期1443-1448,共6页
Nowadays, PD (partial discharge) measurements are a crucial part of the preventive maintenance of electrical equipment within high voltage engineering. Especially for electrical machines, both the supplier and the u... Nowadays, PD (partial discharge) measurements are a crucial part of the preventive maintenance of electrical equipment within high voltage engineering. Especially for electrical machines, both the supplier and the user are interested in the results of PD measurements. However, PDs hardly represent the cause of the failure, more likely they are claimed as the outcome of a failure. This paper deals with the insulation of a 6 kV electrical machine, whereas PD measurements were carried out at a single stator from wound coils. During manufacturing, these coils were equipped with different materials for the OCP (outer corona protection). Using different PD measurement systems and different bandwidths, investigations of the PD behavior of the coils were carried out. Additionally, the surface resistivity of the corona protection was determined. As a result, conclusions for the correlations between the resistance of the OCP as well as the PD behavior are stated. Furthermore, the influence of using different measurement systems, different measuring circuits, and different bandwidths is shown. 展开更多
关键词 PD behavior rotating electrical machine OCP-tapes PD measurement systems PD bandwidths
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Detecting Radiation Effect on AI and AlCu8.5 by Positron Annihilation Doppler Broadening Technique and Electrical Measurements 被引量:1
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作者 Nasser Abdel-Azeem Kamel Emad A. Badawi 《材料科学与工程(中英文版)》 2011年第4期400-405,共6页
关键词 正电子湮没谱 测量技术 多普勒展宽 电气测量 辐射效应 人工智能 检测 电子能带结构
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