scholarly journals Investigation of Factors Causing Nonuniformity in Luminescence Lifetime of Fast-Responding Pressure-Sensitive Paints

Sensors ◽  
2021 ◽  
Vol 21 (18) ◽  
pp. 6076
Author(s):  
Yasuhiro Egami ◽  
Yuya Yamazaki ◽  
Naoto Hori ◽  
Yosuke Sugioka ◽  
Kazuyuki Nakakita
Keyword(s):  
Measurement Accuracy ◽  
Lifetime Distribution ◽  
Luminescence Lifetime ◽  
Imaging Method ◽  
Lifetime Imaging ◽  
Binder Layer ◽  
Depth Direction ◽  
Pressure Sensitive ◽  
Improve Measurement ◽  
Reference Images

Factors that cause nonuniformity in the luminescence lifetime of pressure-sensitive paints (PSPs) were investigated. The lifetime imaging method of PSP does not theoretically require wind-off reference images. Therefore, it can improve measurement accuracy because it can eliminate errors caused by the deformation or movement of the model during the measurement. However, it is reported that the luminescence lifetime of PSP is not uniform on the model, even under uniform conditions of pressure and temperature. Therefore, reference images are used to compensate for the nonuniformity of the luminescence lifetime, which significantly diminishes the advantages of the lifetime imaging method. In particular, fast-responding PSPs show considerable variation in luminescence lifetime compared to conventional polymer-based PSPs. Therefore, this study investigated and discussed the factors causing the nonuniformity of the luminescence lifetime, such as the luminophore solvent, luminophore concentrations, binder thickness, and spraying conditions. The results obtained suggest that the nonuniformity of the luminophore distribution in the binder caused by the various factors mentioned above during the coating process is closely related to the nonuniformity of the luminescence lifetime. For example, when the thickness of the binder became thinner than 8 μm, the fast-responding PSPs showed a tendency to vary significantly in the luminescence lifetime. In addition, it was found that the luminescence lifetime of fast-responding PSP could be changed in the depth direction of the binder depending on the coating conditions. Therefore, it is important to distribute the luminophore uniformly in the binder layer to create PSPs with a more uniform luminescence lifetime distribution.

scholarly journals Effectiveness of Variable-Gain Kalman Filter Based on Angle Error Calculated from Acceleration Signals in Lower Limb Angle Measurement with Inertial Sensors

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Yuta Teruyama ◽  
Takashi Watanabe
Keyword(s):  
Kalman Filter ◽  
Lower Limb ◽  
Measurement Accuracy ◽  
Inertial Sensors ◽  
Angle Measurement ◽  
Angle Error ◽  
Variable Gain ◽  
Improve Measurement ◽  
Kalman Gain ◽  
Acceleration Signals

The wearable sensor system developed by our group, which measured lower limb angles using Kalman-filtering-based method, was suggested to be useful in evaluation of gait function for rehabilitation support. However, it was expected to reduce variations of measurement errors. In this paper, a variable-Kalman-gain method based on angle error that was calculated from acceleration signals was proposed to improve measurement accuracy. The proposed method was tested comparing to fixed-gain Kalman filter and a variable-Kalman-gain method that was based on acceleration magnitude used in previous studies. First, in angle measurement in treadmill walking, the proposed method measured lower limb angles with the highest measurement accuracy and improved significantly foot inclination angle measurement, while it improved slightly shank and thigh inclination angles. The variable-gain method based on acceleration magnitude was not effective for our Kalman filter system. Then, in angle measurement of a rigid body model, it was shown that the proposed method had measurement accuracy similar to or higher than results seen in other studies that used markers of camera-based motion measurement system fixing on a rigid plate together with a sensor or on the sensor directly. The proposed method was found to be effective in angle measurement with inertial sensors.

Research on Data Aggregation Algorithms Based on OPT in Wireless Sensor Networks

2013 ◽  
Vol 427-429 ◽  
pp. 1991-1994
Author(s):  
Xue Wen He ◽  
Le Ping Zheng ◽  
Kuan Gang Fan ◽  
Sun Han ◽  
Qing Mei Cao
Keyword(s):  
Wireless Sensor Networks ◽  
Sensor Networks ◽  
Data Aggregation ◽  
Measurement Accuracy ◽  
Wireless Sensor ◽  
Data Traffic ◽  
Fusion Model ◽  
Design Goal ◽  
Improve Measurement ◽  
Battery Energy

Since wireless sensor networks consist of sensors with limited battery energy, a major design goal is to maximize the lifetime of sensor network. To improve measurement accuracy and prolong network lifetime, reducing data traffic is needed. In the clustering-based wireless sensor networks, a novel data aggregation algorithm based on OPT and Layida Method is proposed. In the proposed method, Layida Method preprocesses data and data fusion model for data integration are used. Its availability is proved by comparing with the results of two existing algorithms.

scholarly journals The Effect of Deflections and Elastic Deformations on Geometrical Deviation and Shape Profile Measurements of Large Crankshafts with Uncontrolled Supports

Sensors ◽  
2020 ◽  
Vol 20 (19) ◽  
pp. 5714
Author(s):  
Krzysztof Nozdrzykowski ◽  
Stanisław Adamczak ◽  
Zenon Grządziel ◽  
Paweł Dunaj
Keyword(s):  
Correlation Analysis ◽  
Quantitative Assessment ◽  
Measurement Accuracy ◽  
Qualitative Comparison ◽  
Elastic Deformations ◽  
Point Support ◽  
Improve Measurement ◽  
Amplitude Spectra ◽  
Geometric Deviations ◽  
Multi Criteria Analysis

This article presents a multi-criteria analysis of the errors that may occur while measuring the geometric deviations of crankshafts that require multi-point support. The analysis included in the paper confirmed that the currently used conventional support method—in which the journals of large crankshafts rest on a set of fixed rigid vee-blocks—significantly limits the detectability of their geometric deviations, especially those of the main journal axes’ positions. Insights for performing practical measurements, which will improve measurement procedures and increase measurement accuracy, are provided. The results are presented both graphically and as discrete amplitude spectra to make a visual, qualitative comparison, which is complemented by a quantitative assessment based on correlation analysis.

scholarly journals Iridium Nanoparticles for Multichannel Luminescence Lifetime Imaging, Mapping Localization in Live Cancer Cells

2018 ◽  
Vol 140 (32) ◽  
pp. 10242-10249 ◽  
Author(s):  
Siobhan M. King ◽  
Sunil Claire ◽  
Rodolfo I. Teixeira ◽  
Abiola N. Dosumu ◽  
Andrew J. Carrod ◽  
...  
Keyword(s):  
Cancer Cells ◽  
Luminescence Lifetime ◽  
Iridium Nanoparticles ◽  
Lifetime Imaging

scholarly journals Thermal properties of thin films made from MoS2 nanoflakes and probed via statistical optothermal Raman method

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Arkadiusz P. Gertych ◽  
Anna Łapińska ◽  
Karolina Czerniak-Łosiewicz ◽  
Anna Dużyńska ◽  
Mariusz Zdrojek ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Thermal Properties ◽  
Measurement Accuracy ◽  
Deep Understanding ◽  
Gaussian Laser Beam ◽  
Large Area ◽  
Heat Management ◽  
Improve Measurement ◽  
Stability Issues

Abstract A deep understanding of the thermal properties of 2D materials is crucial to their implementation in electronic and optoelectronic devices. In this study, we investigated the macroscopic in-plane thermal conductivity (κ) and thermal interface conductance (g) of large-area (mm2) thin film made from MoS2 nanoflakes via liquid exfoliation and deposited on Si/SiO2 substrate. We found κ and g to be 1.5 W/mK and 0.23 MW/m2K, respectively. These values are much lower than those of single flakes. This difference shows the effects of interconnections between individual flakes on macroscopic thin film parameters. The properties of a Gaussian laser beam and statistical optothermal Raman mapping were used to obtain sample parameters and significantly improve measurement accuracy. This work demonstrates how to address crucial stability issues in light-sensitive materials and can be used to understand heat management in MoS2 and other 2D flake-based thin films.

Surface-positioned double-ring to improve traditional infiltrometer for measuring soil infiltration

Soil Research ◽  
2020 ◽  
Vol 58 (3) ◽  
pp. 314
Author(s):  
Jing Zhang ◽  
Shaopeng Li
Keyword(s):  
Hydraulic Conductivity ◽  
Measurement Accuracy ◽  
Soil Column ◽  
Saturated Hydraulic Conductivity ◽  
Experimental Results ◽  
Water Infiltration ◽  
Maximum Relative Error ◽  
Wetting Front ◽  
Double Ring ◽  
Improve Measurement

The installation of a traditional double-ring infiltrometer (DRI) into soil is difficult and time consuming. It results in reduced accuracy because of soil disturbance and water leakage along the gaps between the ring wall and the soil. In this study, a surface-positioned DRI (SPDRI) was suggested to improve measurement accuracy and convenience of the DRI. Laboratory experiments were conducted to evaluate performance of the method in terms of the influence of the lateral flow of water on the accuracy of infiltration rate, average vertical wetting front depth and saturated hydraulic conductivity. A cylindrical soil column was used to simulate the ideal ring infiltrometer (IRI) of the one-dimensional vertical infiltration process for comparison purposes. Experimental results indicated that the infiltration rates measured by the SPDRI and IRI were nearly identical, with maximum relative error (RE) of 18.75%. The vertical wetting front depth of the SPDRI was nearly identical to that of the IRI, with proportional coefficients of 0.97 and R2 > 0.95. Comparison of the soil saturated hydraulic conductivity with those from IRI indicated that the REs were 7.05–10.63% for the SPDRI. Experimental results demonstrated that the SPDRI could improve the measurement accuracy and facilitate the soil water infiltration measurement process.

scholarly journals Luminescence Lifetime Imaging of O2 with a Frequency-Domain-Based Camera System

10.3791/60191 ◽  
2019 ◽  
Author(s):  
Maria Moßhammer ◽  
Vincent V. Scholz ◽  
Gerhard Holst ◽  
Michael Kühl ◽  
Klaus Koren
Keyword(s):  
Frequency Domain ◽  
Luminescence Lifetime ◽  
Camera System ◽  
Lifetime Imaging
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