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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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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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Parameter tuning for configuring and analyzing evolutionary algorithms

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SWARM AND EVOLUTIONARY COMPUTATION 2011年第1期1卷 19-31页

作者： Eiben, A. E. Smit, S. K. Vrije Univ Amsterdam Dept Comp Sci NL-1081 HV Amsterdam Netherlands

In this paper we present a conceptual framework for parameter tuning, provide a survey of tuning methods, and discuss related methodological issues. The framework is based on a three-tier hierarchy of a problem, an evolutionary algorithm (EA), and a tuner. Furthermore, we distinguish problem instances, parameters, and EA performance measures as major factors, and discuss how tuning can be directed to algorithm performance and/or robustness. For the survey part we establish different taxonomies to categorize tuning methods and review existing work. Finally, we elaborate on how tuning can improve methodology by facilitating well-funded experimental comparisons and algorithm analysis. (C) 2011 Elsevier B.V. All rights reserved.

关键词： Evolutionary algorithms Parameter tuning algorithm performance Robustness Experimental methodology

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Strapdown Sculling algorithm Design for Sensor Dynamic Amplitude and Phase-Shift Error

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2012年第6期35卷 1718-1729页

作者： Savage, Paul G. Strapdown Associates Inc Maple Plain MN 55359 USA

Relative phase shift between vibrating angular rate and acceleration inputs can generate significant sculling errors in strapdown computational algorithms when accompanied by inertial sensor-induced dynamic relative phase shift between gyro/accelerometer axes. This paper analyzes the problem and analytically demonstrates that all sculling algorithms can generate large errors under these conditions. Coning algorithms only use gyro inputs, hence, do not exhibit this characteristic because relative sensor-induced phase shift is not present for gyros of the same design configuration in a strapdown sensor assembly. Potential sculling algorithm solution approaches are discussed, focusing on digital sensor filtering as a simple remedy. Using a minimum integral weighted-error-squared digital prefilter design approach, the paper demonstrates that relative sensor-induced phase shift can be effectively removed so that traditionally designed sculling algorithms will accurately operate in frequency regions where input vibrations are expected.

关键词： Inertial Sensor algorithm performance Accelerometer Resonance Frequencies Strapdown Inertial Navigation System Dynamic Response Digital Filters Composite Materials Thermal Expansion Strength of Materials

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Solving the target coverage problem in multilevel wireless networks capable of adjusting the sensing angle using continuous learning automata

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IET COMMUNICATIONS 2022年第2期16卷 151-163页

作者： Qarehkhani, Azam Golsorkhtabaramiri, Mehdi Mohamadi, Hosein Yadollahzadeh-Tabari, Meisam Islamic Azad Univ Babol Branch Dept Comp Engn Babol Iran Islamic Azad Univ Azadshahr Branch Dept Comp Engn Azadshahr Iran

Today, a directional sensor network is a popular environment for solving the target coverage problem. Monitoring all targets in a DSN is a crucial challenge to scholars working in this field of study. Adjusting the angle and range of the sensors can be an efficient technique for improving the network performance. In this way, the network has the most extended lifespan and, at the same time, spends the least time to find the best cover set. In this method, each sensor dynamically adjusts its own sensing angle in order to find the targets by choosing the best range. The present study proposed a continuous learning automata-based method to choose the optimum sensing angle for the sensors in a DSN. Then, to evaluate the proposed algorithm performance, its results were compared to those of a conventional automata-based method whose algorithm worked based on continuous automata. The comparative analysis confirmed the superiority of the proposed method over the conventional automata-based method regarding the extension of the network lifespan.

关键词： target coverage problem conventional automata-based method popular environment wireless sensor networks algorithm performance continuous learning automata-based method DSN directional sensor network multilevel wireless networks network lifespan network performance optimum sensing angle telecommunication computing continuous automata learning automata

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A framework for video abstraction systems analysis and modelling from an operational point of view

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MULTIMEDIA TOOLS AND APPLICATIONS 2010年第1期49卷 7-35页

作者： Valdes, Victor Martinez, Jose M. Univ Autonoma Madrid Escuela Politecn Super E-28049 Madrid Spain

Nowadays the huge amount of video material stored in multimedia repositories makes its search and retrieval a very slow and usually difficult task. Existing video abstraction systems aim to relieve this problem by providing short versions of the original content which ease the search and navigation processes and reduce the browsing time. There are many approaches for video abstraction based on the optimal selection and presentation of a subset of fragments (keyframes, shots, etc.) from the original video attending to different criteria, usually dependent on the application scenario. Nevertheless, given the huge size and growth rate of existing video repositories there is an increasing need for providing efficient techniques. This paper presents a unified taxonomy and a generic architectural model aimed for the study of existing abstraction systems computational performance and characteristics. The taxonomy has been developed taking into account and identifying the operative characteristics of current state of the art video abstraction techniques. The proposed video abstraction architecture model characterizes the stages needed to build a generic abstraction process and establishes the basic architectural aspects and requirements for the modeling of systems with specific operative requirements.

关键词： Video summarization Video abstraction Taxonomy algorithm performance

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