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- 摘要
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- 实验方案
- 产品
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[IEEE 2019 2nd International Colloquium on Smart Grid Metrology (SMAGRIMET) - Split, Croatia (2019.4.9-2019.4.12)] 2019 2nd International Colloquium on Smart Grid Metrology (SMAGRIMET) - Fiber Optic Sensor Cable Based on Hollow Capillary Tube with Three Tightly Encapsulated Optical Fibers
摘要： Fiber optic sensor cable technology is relatively new field that combines a set of scientific and technical disciplines in a special way in order to meet industrial standards. In this paper we discuss one particular design for multipurpose and configuration multivalent optical fiber sensing. It has the potential to integrate more detection and measurement techniques in one cable body and this, in turn, largely contributes to installation cost optimization and directly impacts investment plans and industrial success. The article presents also a unique high-pressure high temperature lab facility conceptualized and constructed for testing and evaluation of this and similar optical fiber sensor cables.
关键词： fiber optic measurements,OFDR,acoustic sensors,BOTDA,BOTDR,DAS,Brillouin effect,optical fiber,pressure sensors,fully distributed optical fiber sensor,monitoring systems,strain sensors,temperature sensors,OTDR
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE International Meeting for Future of Electron Devices, Kansai (IMFEDK) - Kyoto, Japan (2019.11.14-2019.11.15)] 2019 IEEE International Meeting for Future of Electron Devices, Kansai (IMFEDK) - Invited: Possibility of dye-sensitized solar cell as energy harvester
摘要： This paper proposes a statistical approach for section-based fault location in medium voltage (MV) grids with underground cables, using Bayesian inference. The proposed approach considers several important uncertainties in the MV grid, including measurement errors, fault breakdown resistance, and the inaccuracies of zero-sequence parameters. The approach first obtains the prior distribution of the fault position from the component failure database, the readings of the transmitted fault indicators, and the relevant digging activity record. With the estimated prefault grid status and the measured transient voltages/currents, the posterior distribution is then calculated based on Bayes’ theorem. To solve the problem numerically, the Monte Carlo integration is applied and a two-step calculation procedure is proposed. Simulations are performed on a typical European MV feeder to demonstrate the feasibility of the approach. The distribution grid operators can use the calculated posterior distribution to rank the possible faulted sections and to facilitate the restoration process, which can reduce the interruption duration of power supply.
关键词： transient measurements,section-based fault location,Monte Carlo integration,underground cables,Bayesian inference
更新于2025-09-16 10:30:52
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Implementation of data-cube pumpa??probe KPFM on organic solar cells
摘要： An implementation of pump–probe Kelvin probe force microscopy (pp-KPFM) is reported that enables recording the time-resolved surface potential in single-point mode or over a 2D grid. The spectroscopic data are acquired in open z-loop configuration, which simplifies the pp-KPFM operation. The validity of the implementation is probed by measurements using electrical pumping. The dynamical photoresponse of a bulk heterojunction solar cell based on PTB7 and PC71BM is subsequently investigated by recording point-spectroscopy curves as a function of the optical power at the cathode and by mapping 2D time-resolved images of the surface photovoltage of the bare organic active layer.
关键词： Kelvin probe force microscopy (KPFM),time-resolved measurements,bulk heterojunctions,organic photovoltaics,pump–probe configuration,photocarrier dynamics
更新于2025-09-16 10:30:52
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Low-Light Image Enhancement with Semi-Decoupled Decomposition
摘要： Detection of defects in induction machine rotor bars for disassembled motors are required to evaluate machines considered for repair as well as fulfilling incremental quality assurance checks in the manufacture of new machines. Detection of rotor bar defects prior to motor assembly are critical in increasing repair efficiency and assuring the quality of newly manufactured machines. Many methods of detecting rotor bar defects in unassembled motors lack the sensitivity to find both major and minor defects in both cast and fabricated rotors along with additional deficiencies in quantifiable test results and arc-flash safety hazards. A process of direct magnetic field analysis can examine measurements from induced currents in a rotor separated from its stator yielding a high-resolution fingerprint of a rotor’s magnetic field. This process identifies both major and minor rotor bar defects in a repeatable and quantifiable manner appropriate for numerical evaluation without arc-flash safety hazards.
关键词： induction motors,ac motors,electromagnetic measurements,magnetic flux,AC machines,rotors
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Epitaxial GaAs Lift Off via III-VI Layered Compounds
摘要： The global bandwidth shortage facing wireless carriers has motivated the exploration of the underutilized millimeter wave (mm-wave) frequency spectrum for future broadband cellular communication networks. There is, however, little knowledge about cellular mm-wave propagation in densely populated indoor and outdoor environments. Obtaining this information is vital for the design and operation of future fifth generation cellular networks that use the mm-wave spectrum. In this paper, we present the motivation for new mm-wave cellular systems, methodology, and hardware for measurements and offer a variety of measurement results that show 28 and 38 GHz frequencies can be used when employing steerable directional antennas at base stations and mobile devices.
关键词： 5G,cellular,MIMO,millimeter wave propagation measurements,28GHz,directional antennas,38GHz,channel models,mobile communications
更新于2025-09-16 10:30:52
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Distributed Optical Fiber-Based Approach for Soila??Structure Interaction
摘要： Scour is a hydraulic risk threatening the stability of bridges in fluvial and coastal areas. Therefore, developing permanent and real-time monitoring techniques is crucial. Recent advances in strain measurements using fiber optic sensors allow new opportunities for scour monitoring. In this study, the innovative optical frequency domain reflectometry (OFDR) was used to evaluate the effect of scour by performing distributed strain measurements along a rod under static lateral loads. An analytical analysis based on the Winkler model of the soil was carefully established and used to evaluate the accuracy of the fiber optic sensors and helped interpret the measurements results. Dynamic tests were also performed and results from static and dynamic tests were compared using an equivalent cantilever model.
关键词： scour,fiber optic sensors,equivalent length,distributed measurements,winkler model,soil-structure interaction
更新于2025-09-16 10:30:52
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Online measurement of the surface during laser forming
摘要： The laser forming process is characterized by high temperature gradients and localized deformation. The process uses a laser to introduce thermal strains. The localized deformation along with the high temperature gradients is introduced iteratively which creates a complex and dynamic forming process. To understand the dynamic behavior of the process, various models have been used. A limitation of these models is that verification is commonly based on comparison with the final shape. The present work is an attempt to measure the dynamic response during laser forming. This work will present a laser forming setup for measuring the dynamic response of a v-bend. A 2D laser range scanner was used for measuring a line perpendicular to the laser heating scan path. By scanning multiple samples and changing the relative position of the 2D laser range scanner along the laser heating scan path, a surface can be generated. Analysis of the surface shows that the plate undergoes different deformation profiles during forming—this can help in understanding the changes that incur during laser forming. A case study is performed where the experimental results are compared with a state-of-the-art numerical model with good correlation between results. This shows that the measured dynamic response can be used for improved verification of numerical models of laser forming to increase confidence in the numerical results.
关键词： Online measurements,FEM,Laser forming,AISI 304,Bending angle
更新于2025-09-16 10:30:52
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Broadband Determination of the Even- and Odd-Mode Propagation Constants of Coupled Lines Based on Two-Port Measurements
摘要： We describe a method for the broadband measurement of the even- and odd-mode propagation constants of symmetrical coupled transmission lines. The main advantage of the method, its simplicity, lies in the lack of need for four-port measurements. Only two-port measurements are required, and thus just a two-port vector network analyzer (VNA). The accuracy of the results can be increased at the cost of a higher number of measured coupled-line lengths. The new approach has been successfully applied for the determination of coupled microstrip lines in the 2- to 20-GHz frequency band in both simulated and experimental cases. A brief discussion about the repeatability of the microstrip launcher and the adverse effects of radiation is included.
关键词： coupled microstrip lines,transmission line measurements,characterization,Broadband measurements,multiconductor transmission lines,propagation constant
更新于2025-09-12 10:27:22
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[IEEE 2019 Antenna Measurement Techniques Association Symposium (AMTA) - San Diego, CA, USA (2019.10.6-2019.10.11)] 2019 Antenna Measurement Techniques Association Symposium (AMTA) - Waveguide-integrated Rydberg Atom-based RF Field Detector for Near-field Antenna Measurements
摘要： We demonstrate simultaneous amplitude and phase measurements of a radio-frequency (RF) ?eld through the use of a Rydberg atom-based sensor embedded inside a waveguiding structure. This measurement uses the Rydberg atom-based sensor in a mixer con?guration, which requires the presence of a local oscillator (LO) RF ?eld. The waveguiding structure supplies the LO ?eld. The combined waveguide and Rydberg atom system is used to measure phase and amplitude in the near-?eld of a horn antenna to extract the far-?eld pattern.
关键词： far-field pattern,near-field antenna measurements,waveguide,Rydberg atom-based sensor,RF field measurements
更新于2025-09-12 10:27:22
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Production of highly charged ions of rare species by laser-induced desorption inside an electron beam ion trap
摘要： This paper reports on the development and testing of a novel, highly efficient technique for the injection of very rare species into electron beam ion traps (EBITs) for the production of highly charged ions (HCI). It relies on in-trap laser-induced desorption of atoms from a sample brought very close to the electron beam resulting in a very high capture efficiency in the EBIT. We have demonstrated a steady production of HCI of the stable isotope 165Ho from samples of only 1012 atoms (～300 pg) in charge states up to 45+. HCI of these species can be subsequently extracted for use in other experiments or stored in the trapping volume of the EBIT for spectroscopic measurements. The high efficiency of this technique extends the range of rare isotope HCIs available for high-precision atomic mass and spectroscopic measurements. A first application of this technique is the production of HCI of the synthetic radioisotope 163Ho for a high-precision measurement of the QEC-value of the electron capture in 163Ho within the “Electron Capture in Holmium” experiment [L. Gastaldo et al., J. Low Temp. Phys. 176, 876–884 (2014); L. Gastaldo et al., Eur. Phys. J.: Spec. Top. 226, 1623–1694 (2017)] (ECHo collaboration) ultimately leading to a measurement of the electron neutrino mass with an uncertainty on the sub electronvolt level.
关键词： high-precision atomic mass measurements,highly charged ions,spectroscopic measurements,rare isotopes,electron beam ion trap,laser-induced desorption
更新于2025-09-12 10:27:22