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STUDY OF STRAPDOWN NAVIGATION ATTITUDE algorithmS

JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 1995年第2期18卷 287-290页

作者： MUSOFF, H MURPHY, JH Charles Stark Draper Laboratory Inc. Cambridge Massachusetts 02139

Typically coning motion has been used as the input to test the effectiveness of attitude algorithms. Jacobian elliptic functions are also shown to meet the criteria for a test input. Simulations using several of these inputs are performed on Miller's algorithm. Analytical evaluation of a Jacobian elliptic function input would be prohibitive. To alleviate this problem Richardson extrapolation is used to numerically evaluate the algorithms for each test input. Additionally, a method for improving all of the attitude algorithms using interpolation is presented.

关键词： Richardson Extrapolation algorithm performance Navigation Attitude algorithms Taylor Series Quaternions Computing performance Euler Equations Angular Motion Gyroscopes Telemetry

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Design and implementation of symbolic algorithms for the computation of generalized asymptotes

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ANNALS OF MATHEMATICS AND ARTIFICIAL INTELLIGENCE 2023年第4期91卷 537-561页

作者： de Sevilla, Marian Fernandez Benedicto, Rafael Magdalena Perez-Diaz, Sonia Univ Alcala Dept Comp Sci Ctra Madrid BarcelonaKm 336 Madrid 28871 Spain Univ Valencia Dept Elect Engn Av Univ S-N Valencia 46100 Spain Univ Alcala Dept Phys & Math Ctra Madrid BarcelonaKm 336 Madrid 28871 Spain

In this paper we present two algorithms for computing the g-asymptotes or generalized asymptotes, of a plane algebraic curve, c , implicitly or parametrically defined. The asymptotes of a curve c reflect the status of c at points with sufficiently large coordinates. It is well known that an asymptote of a curve c is a line such that the distance between c and the line approaches zero as they tend to infinity. However, a curve c may have more general curves than lines describing the status of c at infinity. These curves are known as g-asymptotes or generalized asymptotes. The pseudocodes of these algorithms are presented, as well as the corresponding implementations. For this purpose, we use the algebra software Maple. A comparative analysis of the algorithms is carried out, based on some properties of the input curves and their results to analyze the efficiency of the algorithms and to establish comparative criteria. The results presented in this paper are a starting point to generalize this study to surfaces or to curves defined by a non-rational parametrization, as well as to improve the efficiency of the algorithms. Additionally, the methods developed can provide a new and different approach in prediction (regression) or classification algorithms in the machine learning field.

关键词： Algebraic curves Infinity branches Convergent branches Approaching curves Generalized asymptotes algorithm performance Hardware usage

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performance-CHARACTERISTICS OF DIFFERENT SOLVING STRATEGIES IN MULTIVARIATE MIXED MODELS

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LIVESTOCK PRODUCTION SCIENCE 1992年第4期30卷 319-332页

作者： GROENEVELD, E KOVAC, M UNIV ILLINOIS DEPT ANIM SCIURBANAIL 61801

Scope and optimization strategies for solving mixed linear models with PEST (general purpose package for multivariate prediction and estimation) are investigated on the basis of three multivariate problems with system sizes of 4116, 30 016 and 472 252 equations. A univariate model with 1 813 168 equations was run to assess the performance of PEST with large problems. Where a submatrix of the mixed model equations was solved simultaneously computing time was reduced to around 1% if compared with complete Gauss-Seidel iteration on data. With the possibility of different incidence matrices for each trait in multivariate models no precorrection of data is required but regressions can be added to the model without much penalty in processing time. Overrelaxation may improve the rate of convergence by 25% and setting a "ceiling" for the number of iterations for the simultaneous part reduced the CPU time by 11%. Cholesky transformation further reduced CPU time between 30 and 50% depending on the required accuracy. The largest system was an animal model for milk yield of nearly 900 000 cows resulting in 1.8 million equations which required 26 Mb of memory during the solving process taking 37 min per round on a SUN 4 workstation.

关键词： algorithm performance MIXED LINEAR MODELS MULTIVARIATE BEST LINEAR UNBIASED PREDICTION

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Generalizations of the Jaccard index and Sørensen index for assessing agreement across multiple readers in object detection and instance segmentation in biomedical imaging

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JOURNAL OF MEDICAL IMAGING 2023年第6期10卷

作者： Durkee, Madeleine S. Lleras, Kyle Drukker, Karen Ai, Junting Cao, Thao Casella, Gabriel Ghosh, Deepjyoti Clark, Marcus R. Giger, Maryellen L. Univ Chicago Dept Radiol Chicago IL 60637 USA Comm Med Phys Chicago IL 60637 USA Univ Chicago Dept Med Sect Rheumatol Chicago IL 60637 USA Gwen Knapp Ctr Lupus andImmunol Res Dept Med Chicago IL 60637 USA

Significance Manual annotations are necessary for training supervised learning algorithms for object detection and instance segmentation. These manual annotations are difficult to acquire, noisy, and inconsistent across *** The goal of this work is to describe and demonstrate multireader generalizations of the Jaccard and Sorensen indices for object detection and instance *** The multireader Jaccard and Sorensen indices are described in terms of "calls," "objects," and number of readers. These generalizations reduce to the equations defined by confusion matrix variables in the two-reader case. In a test set of 50 cell microscopy images, we use these generalizations to assess reader variability and compare the performance of an object detection network (Yolov5) and an instance segmentation algorithm (Cellpose2.0) with a group of five human readers using the Mann-Whitney U-test with Bonferroni correction for *** The multireader generalizations were statistically different from the mean of pairwise comparisons of readers (p < 0.0001). Further, these multireader generalizations informed when a reader was performing differently than the group. Finally, these generalizations show that Yolov5 and Cellpose2.0 performed similarly to the pool of human readers. The lower bound of the one-sided 90% confidence interval for the difference in the multireader Jaccard index between the pool of human readers and the pool of human readers plus an algorithm were -0.019 and -0.016 for Yolov5 and Cellpose2.0, *** Multireader generalizations of the Jaccard and Sorensen indices provide metrics for characterizing the agreement of an arbitrary number of readers on object detection and instance segmentation tasks.

关键词： reader performance reader agreement algorithm performance supervised learning biomedical imaging

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Computational Solutions to Lambert's Problem on Modern Graphics Processing Units

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2015年第7期38卷 1306-U15页

作者： Wagner, Sam Wie, Bong Kaplinger, Brian Iowa State Univ Dept Aerosp Engn Asteroid Deflect Res Center Ames IA 50010 USA Florida Inst Technol Dept Mech & Aerosp Engn Melbourne FL 32901 USA

The Battin, Gooding, and Sun algorithms are able to converge for nearly 100% of all orbit combinations. Both the Gooding and Sun algorithms have approximately the same performance, whereas the Battin algorithm is consistently slower. The performance for each Lambert algorithm, when run on the graphics processing unit (GPU), has been compared. Each Lambert solution algorithm is able to compute tens of millions of solutions per second, with Sun's method having the best performance at nearly 32 million solutions per second. This represents an increase in performance of two orders of magnitude when using GPUs over standard CPU algorithms. Although even the grid search CPU run times are not high when compared with common high-performance computing algorithms, mission optimization algorithms often require run times ranging from hours to multiple days. By offloading computations for solutions to Lambert's problem to GPU(s) and sufficiently parallelizing optimization algorithms, performance increases of up to two orders of magnitude can be realized when compared with standard CPU algorithms. This will allow mission designers to quickly compute complex trajectories when evaluating potential mission architectures.

关键词： Lambert algorithm Graphics Processing Unit algorithm performance Application Programming Interface Orbit Determination Highly Elliptical Orbit High performance Computing Optimization algorithm Search algorithm Mars Missions

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performance analysis of spatial filtering of RF interference in radio astronomy

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2005年第3期53卷 896-910页

作者： van der Tol, S van der Veen, AJ Delft Univ Technol Dept Elect Engn NL-2628 CD Delft Netherlands

Radio astronomical observations are increasingly contaminated by man-made RF interference (RFI). If these signals are continuously present, then they cannot be removed by the usual techniques of detection and blanking. We have previously proposed a spatial filtering technique, where the impact of the interferer is projected out from the estimated covariance data. Assuming that the spatial signature of the interferer is time-varying, several such estimates can be combined to recover the missing dimensions. In this paper, we give a detailed performance analysis of this algorithm. It is shown that the spatial filter introduces a small increase in variance of the estimates (because of the loss in information) and that the algorithm is unbiased in case the true spatial signatures of the interferers are known but that there may be a bias in case the signatures are estimated from the same data. Some of the bias may be removed, and moreover, the bias only affects the auto-correlations, whereas the astronomical information is mostly in the cross-correlations.

关键词： algorithm performance eigenvalues interference cancellation radio astronomy RF interference spatial filtering

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Global performance of metaheuristic optimization tools for water distribution networks

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AIN SHAMS ENGINEERING JOURNAL 2021年第1期12卷 223-239页

作者： Djebedjian, Berge Abdel-Gawad, Hossam A. A. Ezzeldin, Riham M. Mansoura Univ Fac Engn Mech Power Engn Dept Mansoura Egypt Mansoura Univ Fac Engn Irrigat & Hydraul Engn Dept Mansoura Egypt

Numerous metaheuristic optimization algorithms are used for optimal design of water distribution networks. Each algorithm shows dissimilar characteristics depending on the network properties and the sensitivity analysis of the algorithm control variables. New performance metrics of metaheuristic optimization methods are proposed using simple but robust refined metrics and were applied to the available literature data for different algorithms which have previously been used for three popular benchmark water distribution networks. In general, recent performance metrics are devoted to measure effectiveness, efficiency, and reliability in a separate manner, which made some confusion, which is the best?. In the present work, the proposed metrics are used to calculate both of best global and average global performance of different optimization algorithms. The results show that the present metrics have a good distinctive performance between different algorithms. The Fittest individual referenced Differential Evolution is found to be the best algorithm. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of Faculty of Engineering, Ain Shams University.

关键词： Optimization algorithm performance Water distribution networks Metaheuristic optimization algorithms performance metrics

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Comparison of population-based algorithms for optimizing thinnings and rotation using a process-based growth model

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SCANDINAVIAN JOURNAL OF FOREST RESEARCH 2019年第6期34卷 458-468页

作者： Xue, Hailian Makela, Annikki Valsta, Lauri Vanclay, Jerome K. Cao, Tianjian Northwest A&F Univ Yangling Simulat Optimizat Lab Yangling Shaanxi Peoples R China Univ Helsinki Dept Forest Sci Helsinki Finland Southern Cross Univ Forest Res Ctr Lismore NSW Australia

Stand management optimization has long been computationally demanding as increasingly detailed growth and yield models have been developed. Process-based growth models are useful tools for predicting forest dynamics. However, the difficulty of classic optimization algorithms limited its applications in forest planning. This study assessed alternative approaches to optimizing thinning regimes and rotation length using a process-based growth model. We considered (1) population-based algorithms proposed for stand management optimization, including differential evolution (DE), particle swarm optimization (PSO), evolution strategy (ES), and (2) derivative-free search algorithms, including the Nelder-Mead method (NM) and Osyczka's direct and random search algorithm (DRS). We incorporated population-based algorithms into the simulation-optimization system OptiFor in which the process-based model PipeQual was the simulator. The results showed that DE was the most reliable algorithm among those tested. Meanwhile, DRS was also an effective algorithm for sparse stands with fewer decision variables. PSO resulted in some higher objective function values, however, the computational time of PSO was the longest. In general, of the population-based algorithms, DE is superior to the competing ones. The effectiveness of DE for stand management optimization is promising and manifested.

关键词： algorithm performance optimal thinning population-based algorithms process-based model

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DIGITAL IMAGE REGISTRATION BY PHASE CORRELATION BETWEEN BOUNDARY MAPS

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IEE PROCEEDINGS-E COMPUTERS AND DIGITAL TECHNIQUES 1987年第2期134卷 101-104页

作者： MORANDI, C PIAZZA, F CAPANCIONI, R Dipartimento di Elettronica ed Automatica Università di Ancona Ancona Italy

The performance of the phase-correlation image-registration algorithm when greyscale images are replaced by boundary maps is discussed in the light of several experiments. It is found that use of contours only does not substantially degrade the algorithm performance, while the reduced amount of information associated with each image may turn to advantage whenever the bandwidth of the communication channel is concerned.

关键词： optical correlation boundary maps Pattern recognition digital image processing Optical information, image and video signal processing computational complexity algorithm performance phase-correlation image-registration algorithm picture processing communication channel bandwidth

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CONSTRAINED INITIAL GUIDANCE algorithm

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 1990年第2期13卷 193-197页

作者： COCHRAN, JE HAYNES, DA Auburn University Auburn Alabama

An algorithm is presented for determining two-body trajectories that originate on a given two-body orbit, intercept a moving target at a free final time, and are generated by an impulsive velocity change of fixed magnitude. By using a coordinate system defined by the initial and final position vectors of the interceptor, the problem is first reduced to one of solving for the real root of a quartic equation that corresponds to minimum flight time between two specified points subject to the velocity change constraint. An iterative procedure then is used to correct the targeted position until convergence is obtained with respect to the position of the target. Numerical simulation results presented indicate excellent algorithm performance. Typically, less than 20 iterations are needed to reduce miss distance to less than 1 m if perfect target position information is available. The algorithm provides a rapid method of determining the performance boundaries for systems with specified maximum impulse capability. (Author)

关键词： Guidance algorithms algorithm performance Numerical Simulation Satellites Boundary Value Problems Orbital Elements Keplerian Orbit Orbital Boundary Value Projectiles Earth

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