Evaluation of Surface Shortwave Flux Estimates from GOES: Sensitivity to Sensor Calibration

Abstract Parameters derived from satellite observations depend on the quality of the calibration method applied to the raw satellite radiance measurements. This study investigates the sensitivity of absolute reflectance, derived cloud cover, and estimated surface shortwave (SW) downward fluxes to two different calibration methods for the visible sensor aboard the eighth Geostationary Operational Environmental Satellite (GOES-8). The first method was developed at NOAA's National Environmental Satellite, Data, and Information Service (NESDIS), and the second at the NASA Langley Research Center. Differences in visible reflectance ranged from −0.5% to 3%. The average difference in monthly mean cloud amount was ∼3%, and the average difference in monthly mean shortwave downward flux was 5 W m−2. Differences in bias and rms of the SW fluxes when evaluated against ground station measurements were less than 3 W m−2. Neither calibration method was shown to consistently outperform the other. This evaluation yields an estimate of the errors in fluxes that can be attributed to calibration.

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HYBRID ONLINE MOBILE LASER SCANNER CALIBRATION THROUGH IMAGE ALIGNMENT BY MUTUAL INFORMATION

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsannals-iii-1-25-2016 ◽

2016 ◽

Vol III-1 ◽

pp. 25-31 ◽

Cited By ~ 2

Author(s):

Mourad Miled ◽

Bahman Soheilian ◽

Emmanuel Habets ◽

Bruno Vallet

Keyword(s):

Mutual Information ◽

Imaging System ◽

Laser Scanner ◽

Point Clouds ◽

Calibration Method ◽

Online Calibration ◽

Calibration Methods ◽

Laser Calibration ◽

Scanner Calibration

This paper proposes an hybrid online calibration method for a laser scanner mounted on a mobile platform also equipped with an imaging system. The method relies on finding the calibration parameters that best align the acquired points cloud to the images. The quality of this intermodal alignment is measured by Mutual information between image luminance and points reflectance. The main advantage and motivation is ensuring pixel accurate alignment of images and point clouds acquired simultaneously, but it is also much more flexible than traditional laser calibration methods.

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Online Calibration Method for Current Sensors Based on GPS

Energies ◽

10.3390/en12101923 ◽

2019 ◽

Vol 12 (10) ◽

pp. 1923

Author(s):

Shuang Zhao ◽

Jun Liu ◽

Yansong Li

Keyword(s):

Calibration Method ◽

National Standard ◽

Economic Losses ◽

Current Sensor ◽

Sensor Calibration ◽

Gps Receiver ◽

Angular Difference ◽

Online Calibration ◽

Calibration Methods ◽

Current Sensors

At present, most sensor calibration methods are off-line calibration, which not only makes them time-consuming and laborious, but also causes considerable economic losses. Therefore, in this study, an online calibration method of current sensors is proposed to address the abovementioned issues. The principle and framework of online calibration are introduced. One of the calibration indexes is angular difference. In order to accurately verify it, data acquisition must be precisely synchronized. Therefore, a precise synchronous acquisition system based on GPS timing is proposed. The influence of ionosphere on the accuracy of GPS signal is analyzed and a new method for measuring the inherent delay of GPS receiver is proposed. The synchronous acquisition performance of the system is verified by inter-channel synchronization experiment, and the results show that the synchronization of the system is accurate. Lastly, we apply our online calibration method to the current sensor; the experimental results show that the angular difference and ratio difference meet the requirements of the national standard and the accuracy of the online calibration system can be achieved to 0.2 class, demonstrating the effectiveness of the proposed online calibration method.

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A systematic MEMS sensor calibration framework

Journal of Sensors and Sensor Systems ◽

10.5194/jsss-4-97-2015 ◽

2015 ◽

Vol 4 (1) ◽

pp. 97-102 ◽

Cited By ~ 3

Author(s):

A. Dickow ◽

G. Feiertag

Keyword(s):

Pressure Sensors ◽

Calibration Method ◽

Least Square ◽

Sensor Data ◽

Sensor Calibration ◽

Calibration Point ◽

Point Sets ◽

Mems Sensor ◽

Least Square Fit

Abstract. In this paper we present a systematic method to determine sets of close to optimal sensor calibration points for a polynomial approximation. For each set of calibration points a polynomial is used to fit the nonlinear sensor response to the calibration reference. The polynomial parameters are calculated using ordinary least square fit. To determine the quality of each calibration, reference sensor data is measured at discrete test conditions. As an error indicator for the quality of a calibration the root mean square deviation between the calibration polynomial and the reference measurement is calculated. The calibration polynomials and the error indicators are calculated for all possible calibration point sets. To find close to optimal calibration point sets, the worst 99% of the calibration options are dismissed. This results in a multi-dimensional probability distribution of the probably best calibration point sets. In an experiment, barometric MEMS (micro-electromechanical systems) pressure sensors are calibrated using the proposed calibration method at several temperatures and pressures. The framework is applied to a batch of six of each of the following sensor types: Bosch BMP085, Bosch BMP180, and EPCOS T5400. Results indicate which set of calibration points should be chosen to achieve good calibration results.

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The spectral calibration method for a crop nitrogen sensor

Sensor Review ◽

10.1108/sr-04-2015-0051 ◽

2016 ◽

Vol 36 (1) ◽

pp. 48-56 ◽

Cited By ~ 4

Author(s):

Jun Ni ◽

Jifei Dong ◽

Jingchao Zhang ◽

Fangrong Pang ◽

Weixing Cao ◽

...

Keyword(s):

Design Methodology ◽

Measurement Accuracy ◽

Signal To Noise Ratio ◽

Calibration Method ◽

Sensor Calibration ◽

Content Type ◽

Spectral Calibration ◽

Calibration Methods ◽

Detector Method ◽

Standard Detector

Purpose – The purpose of this paper is to improve the accuracy and signal-to-noise ratio (SN) of a crop nitrogen sensor. Design/methodology/approach – The accuracy and wide adaptability of two spectral calibration methods for a crop nitrogen sensor based on standard reflectivity gray plates and standard detector, respectively, were compared. Findings – The calibration method based on standard detector could significantly improve the measurement accuracy and the SN of this crop nitrogen sensor. When compared with the method based on standard gray plates, the measurement accuracy and the SN of the crop nitrogen sensor calibrated based on the standard detector method improved by 50 and 10 per cent, respectively. Originality/value – This research analysed the calibration problems faced by the crop nitrogen sensor (type CGMD302) based on standard gray plates, and proposed a sensor calibration method based on a standard detector. Finally, the results of the two calibration methods were compared in terms of measurement accuracy and the SN of the crop nitrogen sensor.

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The Comparison of Two Stereo Vision Sensor Calibration Methods

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.317-319.397 ◽

2011 ◽

Vol 317-319 ◽

pp. 397-400

Author(s):

Gang Chen ◽

Hua Chen ◽

Yu Bo Guo ◽

Dong Ye

Keyword(s):

Stereo Vision ◽

Nonlinear Distortion ◽

Calibration Method ◽

Sensor Calibration ◽

Vision Sensor ◽

Calibration Methods ◽

Hole Model ◽

Draw Conclusion

This paper presents and comparison two stereo vision sensor calibration methods: Volume template based calibration method and the calibration based on virtual stereo pattern. First method use a premade volume template. Second method use a group of random spatial points that are formed by an infrared LED moved with the probe of CMM. Two methods adopt an ideal pin-hole model that ignores the nonlinear distortion of the cameras. Through compare two calibratioin methods, we can draw conclusion that the first method can be applide to stereo sensor calibration in measurement field and the second method could gain higher calibrating precision.

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The Calibration Method of Thermal Heat Flux Sensor Based on Wireless Sensor Networks

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.651-653.538 ◽

2014 ◽

Vol 651-653 ◽

pp. 538-542

Author(s):

Xiao Shi Zheng ◽

Guang He Cheng ◽

Qing Long Meng ◽

Feng Qi Hao ◽

Xuan Cai Xu ◽

...

Keyword(s):

Heat Flux ◽

Wireless Sensor Networks ◽

Sensor Networks ◽

Calibration Method ◽

Wireless Sensor ◽

Heat Flux Sensor ◽

Sensor Calibration ◽

Advantages And Disadvantages ◽

Calibration Methods ◽

Flux Sensor

This paper analyzed the advantages and disadvantages of existing heat flux sensor calibration methods, proposed a calibration method of thermal heat flux sensor based on wireless sensor networks. Experimental results showed that the detection error was reduced from 6% to 2% after calibration. The proposed method has many advantages, such as short calibration time, accurate results, easy installation as well as batching calibration. In a word, this method is available to calibrate heat flux sensors and will have an important significance for accurate measurement of heat flux.

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Robust and Accurate Hand–Eye Calibration Method Based on Schur Matric Decomposition

Sensors ◽

10.3390/s19204490 ◽

2019 ◽

Vol 19 (20) ◽

pp. 4490

Author(s):

Liu ◽

Wu ◽

Keyword(s):

Outlier Detection ◽

Degrees Of Freedom ◽

Data Preprocessing ◽

Calibration Method ◽

Translation Vector ◽

Observation Data ◽

Calibration Methods ◽

Minimal Configuration ◽

New Perspective

To improve the accuracy and robustness of hand–eye calibration, a hand–eye calibration method based on Schur matric decomposition is proposed in this paper. The accuracy of these methods strongly depends on the quality of observation data. Therefore, preprocessing observation data is essential. As with traditional two-step hand–eye calibration methods, we first solve the rotation parameters and then the translation vector can be immediately determined. A general solution was obtained from one observation through Schur matric decomposition and then the degrees of freedom were decreased from three to two. Observation data preprocessing is one of the basic unresolved problems with hand–eye calibration methods. A discriminant equation to delete outliers was deduced based on Schur matric decomposition. Finally, the basic problem of observation data preprocessing was solved using outlier detection, which significantly improved robustness. The proposed method was validated by both simulations and experiments. The results show that the prediction error of rotation and translation was 0.06 arcmin and 1.01 mm respectively, and the proposed method performed much better in outlier detection. A minimal configuration for the unique solution was proven from a new perspective.

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Development of a Non-Invasive Calibration Method for Ocular Tactile Tonometry

Volume 3A: Biomedical and Biotechnology Engineering ◽

10.1115/imece2013-63380 ◽

2013 ◽

Author(s):

Eniko T. Enikov ◽

Péter P. Polyvás

Keyword(s):

Calibration Method ◽

Calibration Procedure ◽

Superior Performance ◽

Sensor Calibration ◽

Ann Model ◽

Element Analysis ◽

Reduced Order ◽

Non Invasive ◽

Calibration Methods ◽

Artificial Neural Network Ann

This article describes a novel method of indirect estimation of intra-ocular pressure using tactile sensors. Two sensor calibration methods have been demonstrated: an artificial neural network (ANN) model and a phenomenological reduced-parameter model based on finite element analysis. The ANN method showed superior performance with an accuracy of +/− 0.7 mmHg, while the reduced order method showed an accuracy of +/− 3.11 mmHg. The latter method however allows calibration of the tactile tonometer from a single pressure measurement if the geometry of the probes is known and satisfying certain solvability conditions. The ANN method was demonstrated using experiment data, while the reduced-order model was tested numerically. Due to its indirect and non-invasive nature, the proposed tactile measurement method can be used in the development of a self-administered home tonometer for management of glaucoma, however the presence of an eye lid might require modification of the calibration procedure outlined here.

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Dissolved Oxygen Measurement in Seawater and Sensor Calibration Method

E3S Web of Conferences ◽

10.1051/e3sconf/202129902017 ◽

2021 ◽

Vol 299 ◽

pp. 02017

Author(s):

Shun Gao ◽

Yingying Zhang ◽

Xiandong Feng ◽

Da Yuan ◽

Bingwei Wu ◽

...

Keyword(s):

Dissolved Oxygen ◽

Automatic Monitoring ◽

Calibration Method ◽

Oxygen Sensors ◽

Sensor Calibration ◽

Advantages And Disadvantages ◽

In Situ Calibration ◽

Laboratory Calibration ◽

Calibration Methods ◽

Working Principle

The development and key calibration methods of the sensors for the measurement and automatic monitoring of dissolved oxygen in seawater have always been the research focus in the field of Marine monitoring technology. This paper summarizes the measurement methods of dissolved oxygen in seawater, the working principle and advantages and disadvantages of different dissolved oxygen sensors, and the research on calibration methods of mainstream optical dissolved oxygen sensors. Especially for optical dissolved oxygen sensors with better stability, longer service life and stronger anti-interference ability, several laboratory calibration methods which have been developed and applied, as well as in situ calibration methods which are still in the research stage are analyzed.

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