- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - New Traceability Concept in RF Inductance Measurements
摘要： National Metrology Institute of Japan (NMIJ) is developing a reference inductance standard using air dielectric coaxial transmission lines that can be used beyond MHz. We report on the structure and traceability system of this reference inductance standard. NMIJ is also developing an inductance measurement method using group delay measurement. A 50 nH reference inductance standard was developed and the inductance measurement method using group delay verified.
关键词： traceability,group delay,air line,reference standard,vector network analyzer,inductance
更新于2025-09-10 09:29:36
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Uncertainty of the Ohm Using Cryogenic and Non-Cryogenic Bridges
摘要： We describe recent scaling measurements to decade resistance levels based on both cryogenic and non-cryogenic current comparator bridges. National measurement institutes and the International Bureau of Weights and Measures derive traceability for the SI ohm using the quantum Hall effect, with the primary comparisons made at the resistance value RK-90/2 = 12906.4035 ?. Cryogenic current comparator scaling methods are preferred since large resistance ratios of 100 or more are achieved with unsurpassed uncertainty. The quantized Hall resistance standard based on graphene allow less complex and more cost-effective room-temperature resistance bridges to provide SI traceability.
关键词： traceability,cryogenic current comparator,quantized Hall resistance,direct current comparator,standard resistor
更新于2025-09-10 09:29:36
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Establishment of RF Power Sensor Calibration at RCM - LIPI
摘要： Industries especially telecommunication and aviation industries require RF power sensor calibration. Research Center for Metrology (RCM) – LIPI as National Metrology Institute of Indonesia is responsible to establish RF power sensor calibration. The RF power sensor calibration system in the frequency range of 10 MHz to 18 GHz has been established at RCM - LIPI to build the measurement traceability of RF power sensor in Indonesia. Modification to the conventional direct comparison transfer method has generated more accurate measurement results. Currently, the calibration system is already used to calibrate RF power sensors from calibration laboratories and industries in Indonesia.
关键词： calibration,Accurate power,direct comparison transfer,traceability,RF power sensor
更新于2025-09-10 09:29:36
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - A PMU Calibration System
摘要： There is a need for traceable calibrations of Phasor measurement units, which measures the phase angle of power system signals with respect to the universal time. This paper describes the design of such a calibration system. The system utilizes a fast A-D converter, synchronized to the Swedish time and frequency realization. The speed and synchronization makes the calibration and adjustment fast and relatively straight-forward. Coaxial dividers and shunts are used for system control. The goal is a three-phase system with an angular uncertainty in the order of, or better than ±0.002° or ±100 ns.
关键词： calibration,traceability,UTC,Measurement,phasor measurement standards,phase angle
更新于2025-09-10 09:29:36
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Prototype of the Near-Infrared Spectroscopy Expert System for Particleboard Identification
摘要： The overall goal of this work was to develop a prototype expert system assisting quality control and traceability of particleboard panels on the production floor. Four different types of particleboards manufactured at the laboratory scale and in industrial plants were evaluated. The material differed in terms of panel type, composition, and adhesive system. NIR spectroscopy was employed as a pioneer tool for the development of a two-level expert system suitable for classification and traceability of investigated samples. A portable, commercially available NIR spectrometer was used for nondestructive measurements of particleboard panels. Twenty-five batches of particleboards, each containing at least three independent replicas, was used for the original system development and assessment of its performance. Four alternative chemometric methods (PLS-DA, kNN, SIMCA, and SVM) were used for spectroscopic data classification. The models were developed for panel recognition at two levels differing in terms of their generality. In the first stage, four among twenty-four tested combinations resulted in 100% correct classification. Discrimination precision with PLS-DA and SVMC was high (>99%), even without any spectra preprocessing. SNV preprocessed spectra and SVMC algorithm were used at the second stage for panel batch classification. Panels manufactured by two producers were 100% correctly classified, industrial panels produced by different manufacturing plants were classified with 98.9% success, and the experimental panels manufactured in the laboratory were classified with 63.7% success. Implementation of NIR spectroscopy for wood-based product traceability and quality control may have a great impact due to the high versatility of the production and wide range of particleboards utilization.
关键词： traceability,quality control,expert system,NIR spectroscopy,particleboard
更新于2025-09-10 09:29:36
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Metrological Problems of Modern Spectral Pyrometry
摘要： Metrological problems that arise in the measurement of the temperature of physical objects performed by means of pyrometers, where the emissivity of the particular object differs from unity and may vary as a function of wavelength, are considered. Methods of correction of spectral (CT) ratio pyrometers are analyzed. A disturbance in the traceability of pyrometers provided with components for correction to the primary standard of the unit of temperature is identi? ed. Recommendations for establishing traceability are given.
关键词： traceability,radiation capacity,emissivity coef? cient,pyrometry
更新于2025-09-09 09:28:46