 Subjects -> INSTRUMENTS (Total: 62 journals)
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- An improved deep residual network with multiscale feature fusion for
rotating machinery fault
diagnosis- Authors: Feiyue Deng; Hao Ding, Shaopu Yang Rujiang Hao
First page: 024002
Abstract: Intelligent mechanical fault diagnosis algorithms based on deep learning have achieved considerable
success in recent years. However, degradation of the diagnostic accuracy and operational speed has
been significant due to unfavorable working conditions and increasing network depth. An improved
version of ResNets is proposed in this paper to address these issues. The advantages of the proposed
network are presented as follows. Firstly, a multi-scale feature fusion block was designed, to
extract multi-scale fault feature information. Secondly, an improved residual block based on
depthwise separable convolution was used to improve the operational speed and alleviate the
computational burden of the network. The effectiveness of the proposed network was validated by
discriminating between diverse health states in a gearbox under normal and noisy conditions. The
experimental results show that the proposed network model has a higher classification accuracy than
the classical convoluti...
Citation: Measurement Science and Technology
PubDate: 2020-11-26T00:00:00Z
DOI: 10.1088/1361-6501/abb917
Issue No: Vol. 32, No. 2 (2020)
- Ruthenium-based fast-responding pressure-sensitive paint for measuring
small pressure fluctuation in
low-speed flow field- Authors: Y Egami; Y Hasegawa, Y Matsuda, T Ikami H Nagai
First page: 024003
Abstract: A sprayable fast-responding pressure-sensitive paint (fast-PSP) has been developed to measure
time-resolved small pressure fluctuation on model surfaces. To realize PSP with fast response, high
robustness, and high luminescence intensity, we have developed a novel ruthenium complex-based
fast-PSP. The binder layers of the proposed fast-PSP were prepared by mixing
room-temperature-vulcanizing silicone (silicone) and titanium dioxide (TiO 2 ) particles with
different sizes and their effects on the properties including the time response, pressure
sensitivity, and luminescence intensity were investigated. The effects of the hydrophilic and
hydrophobic surface treatments of TiO 2 particle on the structure and mechanical robustness of the
binder layer were also studied. The developed fast-PSP was applied to the flow field measurements
behind a square cylinder and was evaluated. We have succeeded in obtaining time-series data of
pressure fluctuation with high accurac...
Citation: Measurement Science and Technology
PubDate: 2020-11-26T00:00:00Z
DOI: 10.1088/1361-6501/abb916
Issue No: Vol. 32, No. 2 (2020)
- Accuracy evaluation of geometric error calibration using a laser tracer
via a formulaic approach- Authors: Hongdong Cong; Jun Zha, Linhui Li, Yipeng Li Yaolong Chen
First page: 025003
Abstract: In this work, we examine the accuracy of the geometric error calibration of machine tools using a
laser tracer, via the multilateration or sequential multilateration principle. An uncertainty
analysis of geometric errors or target point coordinates, based on the Monte-Carlo method, is often
adopted to assess the accuracy of measurement results. However, this approach is not comprehensive,
and can be time-consuming. This paper adopts the average volumetric localization accuracy to assess
the quality of geometric error calibration, where the accuracy is evaluated approximately by means
of a formulaic method, based on the multivariate law of propagation of uncertainty. Using this
method, the accuracy of measurement results can be denoted quantitatively with a single indicator,
and the influence of measurement strategy on measurement accuracy can be analyzed more intuitively.
To further improve the average volumetric localization accuracy, we employ an optimization method
for the me...
Citation: Measurement Science and Technology
PubDate: 2020-11-26T00:00:00Z
DOI: 10.1088/1361-6501/abb9e8
Issue No: Vol. 32, No. 2 (2020)
- Time-of-flight ranging method by measuring pulse laser phase based on
field-programmable gate array
digital mixing- Authors: Min Tao; Xiaobin Gong, Yu Hou, Baohua Li, Junfeng Song, Jian Chen Fengli Gao
First page: 025004
Abstract: We propose a time-of-flight ranging method by measuring the pulse laser phase based on
field-programmable gate array (FPGA) digital mixing, in which accurate laser ranging with a total
digital system is realized by combining one FPGA chip with a simple laser transmitting and receiving
circuit. The system has the advantage of simple structure, reliable operation, low manufacturing
cost and easy integration. Experimental results show that compared with the pulse laser ranging
method using commercial time-to-digital converter chips, it can realize precise measurement of
distance, and the measurement error can be significantly reduced. In addition, this method has
better performance of ranging accuracy.
Citation: Measurement Science and Technology
PubDate: 2020-11-26T00:00:00Z
DOI: 10.1088/1361-6501/abb960
Issue No: Vol. 32, No. 2 (2020)
- Assay of direct digital output floating-wiper resistive displacement
sensor- Authors: Aparna Mohan; S Mohanasankar V Jagadeesh Kumar
First page: 025101
Abstract: The principle of operation of a successive approximation type direct displacement to digital
converter for a floating-wiper resistive potentiometric sensor, presented earlier, is analyzed in
detail to ascertain possible sources of error that can affect the performance of the transducer.
Based on the analysis the method is suitably modified to improve its performance. To establish the
efficacy of the altered scheme, a prototype signal conditioning circuit has been built and tested
using both an emulated sensor and a prototype sensor. While the worst-case error in the former was
found to be 0.5%, it was less than 0.8% in the latter. The test results indicate that the digital
output is directly proportional to the per-unit displacement and is independent of the value of the
coupling capacitance between the floating-wiper and the resistive element.
Citation: Measurement Science and Technology
PubDate: 2020-11-26T00:00:00Z
DOI: 10.1088/1361-6501/abbf0b
Issue No: Vol. 32, No. 2 (2020)
- Development of a biaxial grid-coil-type electromagnetic acoustic
transducer- Authors: Li-Jian Yang; Jia Zhang, Yan-Hao Xing, Song-Wei Gao, Zhe Xie Hong-Wen Fu
First page: 025102
Abstract: This study proposes a grid-coil-type transducer to achieve the simultaneous detection of axial and
circumferential cracks in the pipeline, reduce the number of permanent magnets in dynamic detection,
and improve crack detection efficiency. The proposed system can detect biaxial cracks in the
pipeline. Based on Biot–Savart’s Law, a mathematical model is established between the magnetic
induction intensity and the coil of the electromagnetic acoustic transducer to determine the
influence on the conductor. Experiments verify the relationship between the guided wave propagation
characteristics of the grid-coil-type electromagnetic acoustic transducer and the ability to detect
biaxial cracks. Results show that the grid-coil-type electromagnetic acoustic transducer can
generate the biaxial ultrasonic guided wave propagating along the axial and circumferential
pipeline, in which cracks are thereby simultaneously detected. Thus, the grid-coil-type
electromagnetic acoustic transducer inc...
Citation: Measurement Science and Technology
PubDate: 2020-11-26T00:00:00Z
DOI: 10.1088/1361-6501/abbc88
Issue No: Vol. 32, No. 2 (2020)
- High enhancement factor of SERS probe based on silver nano-structures
deposited on a silica
microsphere by laser-assisted photochemical method
- Authors: Huy Bui; Thuy Van Nguyen, Thanh Son Pham, Van Hoi Pham Thanh Binh Pham
First page: 025109
Abstract: The high enhancement factor (EF) of surface-enhanced Raman (SERS) probes is an important parameter
for high-sensitivity Raman scattering measurement applied to environment control. In this article,
we present a SERS probe based on silver nano-structures deposited on silica microsphere surfaces
made by the laser-assisted photochemical method and reflection converging mirror for a high EF Raman
measurement of ultralow organic compound concentration inliquid environments. The laser-assisted
photochemical method can synthesize and homogeneously deposit nano-silvers on a silica microsphere,
and the reflection converging mirror can collect more Raman signal to the photo-detector and give
high Raman enhancement of the SERS probe. The SERS-activity of the probe is verified by the
detection of ultralow concentrations of Rhodamine 6 G in aqueous solutions in the range of 10 −4 –10
−10 M. The obtained results show that the proposed SERS probe has an increase of collected...
Citation: Measurement Science and Technology
PubDate: 2020-11-28T00:00:00Z
DOI: 10.1088/1361-6501/abab20
Issue No: Vol. 32, No. 2 (2020)
- Squeeze excitation densely connected residual convolutional networks for
specific emitter
identification based on measured signals- Authors: Zining Wan; Deguo Zeng, Wenhai Wang, Xinwei Chen, Zeyin Zhang, Fuyuan Xu, Xuanyu Mao Xinggao Liu
First page: 025110
Abstract: Specific emitter identification (SEI) refers to the process of distinguishing emitter individuals,
which is important for electric support measure systems. Traditional SEI methods are based on
hand-crafted features and have the problem of low accuracy. A novel convolutional neural network
(CNN) approach, named squeeze excitation densely connected residual convolutional network (SEDCRN)
approach, is therefore proposed. SEDCRN can directly recognize signals without complex
preprocessing. It obtains the beneficial advantage of rediscovering new, more useful new features
from low-level information and reducing feature redundancy by embedding the squeeze excitation
module and residual connections into the densely connected convolutional structure. BesideIn
addition, SEDCRN adopts center loss as an auxiliary loss function, which can further enhance the
ability of feature learning and expression, especially for SEI tasks. The proposed approach is
evaluated using a real automatic, depen...
Citation: Measurement Science and Technology
PubDate: 2020-11-28T00:00:00Z
DOI: 10.1088/1361-6501/abb0c0
Issue No: Vol. 32, No. 2 (2020)
- Single image molecular tagging velocimetry
- Authors: Pedro Antonio de Souza Matos; Luiz Gilberto Barreta, Cristiane Aparecida Martins Dermeval Carinhana Jr
First page: 025301
Abstract: A single-image nitric-oxide molecular tagging velocimetry (NO-MTV) is reported and employed in a
real air driven hypersonic shock tunnel and provided velocities of 3240 ± 170(5.2%) and 3030 ±
160(5.3%) m ##IMG## [http://ej.iop.org/images/0957-0233/32/2/025301/mstabbba2ieqn1.gif]
{$\mathrm{s}^{-1}$} , insignificantly different from previous results of 3037 ± 98(3.2%) obtained
by an ordinary multi-image MTV technique. The proposed methodology relies on an one-dimensional
analytical description of the spatial intensity profile registered by a single MTV image.
Citation: Measurement Science and Technology
PubDate: 2020-11-28T00:00:00Z
DOI: 10.1088/1361-6501/abbba2
Issue No: Vol. 32, No. 2 (2020)
- RainbowPIV with improved depth resolution—design and comparative
study with TomoPIV- Authors: J Xiong; A A Aguirre-Pablo, R Idoughi, S T Thoroddsen W Heidrich
First page: 025401
Abstract: RainbowPIV is a recent imaging technology, proposed for time-resolved 3D-3C fluid velocity
measurement using a single RGB camera. It dramatically simplifies hardware setup and calibration
procedures as compared to alternative 3D-3C measurement approaches. RainbowPIV combines optical
design and tailored reconstruction algorithms, and earlier preliminary studies have demonstrated its
ability to extract physically constrained fluid vector fields. This article addresses the issue of
limited axial resolution, the major drawback of the original RainbowPIV system. We validate the new
system with a direct, quantitative comparison with four-camera Tomo-PIV on experimental data. The
reconstructed flow vectors of the two approaches exhibit a high degree of consistency, with the
RainbowPIV results explicitly guaranteeing physical properties, such as divergence free velocity
fields for incompressible fluid flows.
Citation: Measurement Science and Technology
PubDate: 2020-11-28T00:00:00Z
DOI: 10.1088/1361-6501/abb0ff
Issue No: Vol. 32, No. 2 (2020)
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