Trinocular adaptive window size disparity estimation algorithm and its real-time hardware

Abstract The quantitative precipitation estimate (QPE) algorithm developed and described in Part I was validated using data collected from 33 Weather Surveillance Radar 1988-Doppler (WSR-88D) radars on 37 calendar days east of the Rocky Mountains. A key physical parameter to the algorithm is the parameter alpha α, defined as the ratio of specific attenuation A to specific differential phase KDP. Examination of a significant sample of tropical and continental precipitation events indicated that α was sensitive to changes in drop size distribution and exhibited lower (higher) values when there were lower (higher) concentrations of larger (smaller) rain drops. As part of the performance assessment, the prototype algorithm generated QPEs utilizing a real-time estimated and a fixed α were created and evaluated. The results clearly indicated ~26% lower errors and a 26% better bias ratio with the QPE utilizing a real-time estimated α as opposed to using a fixed value as was done in previous studies. Comparisons between the QPE utilizing a real-time estimated α and the operational dual-polarization (dual-pol) QPE used on the WSR-88D radar network showed the former exhibited ~22% lower errors, 7% less bias, and 5% higher correlation coefficient when compared to quality controlled gauge totals. The new QPE also provided much better estimates for moderate to heavy precipitation events and performed better in regions of partial beam blockage than the operational dual-pol QPE.

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High-precision roll attitude estimation of decoupled canards relative to the projectile body using bipolar hall-effect sensors

Journal of Intelligent & Fuzzy Systems ◽

10.3233/jifs-189718 ◽

2021 ◽

pp. 1-9

Author(s):

Tingting Yin ◽

Zhong Yang ◽

Youlong Wu ◽

Fangxiu Jia

Keyword(s):

Hall Effect ◽

Real Time ◽

High Precision ◽

Solution Method ◽

Estimation Method ◽

Estimation Algorithm ◽

Attitude Estimation ◽

Fuzzy Algorithms ◽

Positioning Method ◽

Hall Effect Sensors

The high-precision roll attitude estimation of the decoupled canards relative to the projectile body based on the bipolar hall-effect sensors is proposed. Firstly, the basis engineering positioning method based on the edge detection is introduced. Secondly, the simplified dynamic relative roll model is established where the feature parameters are identified by fuzzy algorithms, while the high-precision real-time relative roll attitude estimation algorithm is proposed. Finally, the trajectory simulations and grounded experiments have been conducted to evaluate the advantages of the proposed method. The positioning error is compared with the engineering solution method, and it is proved that the proposed estimation method has the advantages of the high accuracy and good real-time performance.

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Full-Observable Three-Phase State Estimation Algorithm Applied to Electric Distribution Grids

Energies ◽

10.3390/en12071327 ◽

2019 ◽

Vol 12 (7) ◽

pp. 1327 ◽

Cited By ~ 7

Author(s):

Thiago Soares ◽

Ubiratan Bezerra ◽

Maria Tostes

Keyword(s):

State Estimation ◽

Real Time ◽

Distribution Systems ◽

Phase State ◽

Reactive Power ◽

Estimation Algorithm ◽

Load Flow ◽

Electrical Network ◽

The Real ◽

Three Phase

This paper proposes the development of a three-phase state estimation algorithm, which ensures complete observability for the electric network and a low investment cost for application in typical electric power distribution systems, which usually exhibit low levels of supervision facilities and measurement redundancy. Using the customers´ energy bills to calculate average demands, a three-phase load flow algorithm is run to generate pseudo-measurements of voltage magnitudes, active and reactive power injections, as well as current injections which are used to ensure the electrical network is full-observable, even with measurements available at only one point, the substation-feeder coupling point. The estimation process begins with a load flow solution for the customers´ average demand and uses an adjustment mechanism to track the real-time operating state to calculate the pseudo-measurements successively. Besides estimating the real-time operation state the proposed methodology also generates nontechnical losses estimation for each operation state. The effectiveness of the state estimation procedure is demonstrated by simulation results obtained for the IEEE 13-bus test network and for a real urban feeder.

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Improved Disparity Estimation Algorithm Based on PSMNet

10.1109/ccdc52312.2021.9602063 ◽

2021 ◽

Author(s):

Juan Du ◽

Yongchao Tang ◽

Bohang Li ◽

Dengping Lin ◽

Juan Huang

Keyword(s):

Estimation Algorithm ◽

Disparity Estimation

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Synergistic real-time compensation of tracking and contouring errors for precise parametric curved contour following systems

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406217736340 ◽

2017 ◽

Vol 232 (19) ◽

pp. 3367-3383 ◽

Cited By ~ 3

Author(s):

De-Ning Song ◽

Jian-Wei Ma ◽

Zhen-Yuan Jia ◽

Feng-Ze Qin ◽

Xiao-Xuan Zhao

Keyword(s):

Real Time ◽

High Precision ◽

Tracking Error ◽

Estimation Algorithm ◽

Computer Numerical Control ◽

Numerical Control ◽

System Structure ◽

Parametric Curve ◽

Contouring Error ◽

Contour Following

The tracking and contouring errors are inevitable in real computer numerical control contour following because of the reasons such as servo delay and dynamics mismatch. In order to improve the motion accuracy, this paper proposes a synergistic real-time compensation method of tracking and contouring errors for precise parametric curve following of the computer numerical control systems. The tracking error for each individual axis is first compensated, by using the feed-drive models with the consideration of model uncertainties, to enhance the tracking performances of all axes. Further, the contouring error is estimated and compensated to improve the contour accuracy directly, where a high-precision contouring-error estimation algorithm, based on spatial circular approximation of the desired contour neighboring the actual motion position, is presented. Considering that the system structure is coupled after compensation, the stability of the coupled system is analyzed for design of the synergistic compensator. Innovative contributions of this study are that not only the contouring-error can be estimated with a high precision in real time, but also the tracking and contouring performances can be simultaneously improved although there exist modeling errors and disturbances. Simulation and experimental tests demonstrate the effectiveness and advantages of the proposed method.

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