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Multipath Error Modeling Methodology for GNSS Integrity Monitoring Using a Global Optimization Strategy

Xinqi Fang, Dan Song, Chuang Shi, Lei Fan, Ziye Hu
2022 Remote Sensing  
Valid multipath error model is the prerequisite for high-performance GNSS integrity monitoring. It is indispensable to civil aviation and other Safety-of-Life (SoL) users.  ...  In addition, the new model form with two inflation factors brings average CDF difference reduction of 67.4% at B1I and 50.6% at B3I, which means significantly mitigation in terms of conservatism.  ...  Acknowledgments: We are sincerely grateful for the data support of IGS, the effort of respectful reviewers and academic editor in improving this article, and the timely assistance of assistant editor.  ... 
doi:10.3390/rs14092130 fatcat:zptrk6qpnvfitfjuqamw2e7edu

An advanced residual error model for tropospheric delay estimation

Szabolcs Rózsa, Bence Ambrus, Ildikó Juni, Pieter Bastiaan Ober, Máté Mile
2020 GPS Solutions  
We introduce a new approach to derive residual tropospheric delay error models using the extreme value analysis technique.  ...  Seventeen years of global numerical weather model fields are analyzed, and new residual error models are derived for some recently developed tropospheric delay models.  ...  Acknowledgements : Open access funding provided by Budapest University of Technology and Economics.  ... 
doi:10.1007/s10291-020-01017-7 fatcat:ftcmvakq7bcs3ln4buio6nyi3u

An Error Overbounding Method Based on a Gaussian Mixture Model with Uncertainty Estimation for a Dual-Frequency Ground-Based Augmentation System

Zhen Gao, Kun Fang, Zhipeng Wang, Kai Guo, Yuan Liu
2022 Remote Sensing  
This conservatism may cause false alarms and diminish availability.  ...  However, the Ifree algorithm outputs the errors of two frequencies. The protection level obtained via the traditional Gaussian overbound is overconservative.  ...  Acknowledgments: The authors would like to thank the researchers at the National Key Laboratory of CNS/ATM for their advice and interests.  ... 
doi:10.3390/rs14051111 fatcat:vp4yyyc44fa2hlvezzs2sgci3e

A Class of PID Controllers Tuned in Fractional Representation

Roman Prokop, Jiří Korbel, Radek Matušu
2012 IFAC Proceedings Volumes  
In the paper, this parameter is used for aperiodic tuning of PI controllers. The methodology is utilized for autotuning principles and for robust applications.  ...  Interval perturbations in controlled systems and robustness of proposed algorithms are outlined through the value set concept, zero exclusion condition and Kharitonov theorem.  ...  On the other hand, the investigation of robust stability for "overbounding" interval polynomial can be superfluously conservative as will be shown later.  ... 
doi:10.3182/20120328-3-it-3014.00109 fatcat:cjus7irhwng7hirn2zhbp7gp4a

Robust Stability and Performance Analysis for State-Space Systems via Quadratic Lyapunov Bounds

Dennis S. Bernstein, Wassim M. Haddad
1990 SIAM Journal on Matrix Analysis and Applications  
These are problems of robust stability and performance analysis.  ...  This technique has been extensively developed for both analysis and synthesis (see, e.g., 8 ]-37 ).  ...  Daubendiek for producing the numerical results in 11. Note added in proof. The assumption x(0) 0 in (2.2) is stronger than necessary for the treatment of (2.4).  ... 
doi:10.1137/0611017 fatcat:kbnymlviuvbajiwjdmjhfyfxne

Optimal Popov controller analysis and synthesis for systems with real parameter uncertainties

J.P. How, E.G. Collins, W.M. Haddad
1996 IEEE Transactions on Control Systems Technology  
Recent research has investigated the use of absolute stability criteria to develop less conservative analysis tests for systems with linear and nonlinear real parameter uncertainties.  ...  Robust performance analysis plays an important role in the design of controllers for uncertain multivariable systems.  ...  Grocott, and Dr. D. Miller).  ... 
doi:10.1109/87.486347 fatcat:wsrr3idwcjb6hif5mssjwoh7se

Estimation of model quality

Brett Ninness, Graham C. Goodwin
1995 Automatica  
The problem of marrying system identification and modern robust control theory has resulted in significant research activity. A survey of the outcomes of this effort is presented.  ...  Acknowledgemenr-The authors are very grateful to the reviewers for their many valuable comments that greatly improved this work.  ...  The tools are mainly those of functional analysis, operator theory and analytic topology, which may be intimidating for a practitioner, but for the theoretician allows such things as the elegant unification  ... 
doi:10.1016/0005-1098(95)00108-7 fatcat:pe37yg5uhfedrbqjhwi54e46z4

Estimation of Model Quality

Brett Ninness, Graham Goodwin
1994 IFAC Proceedings Volumes  
The problem of marrying system identification and modern robust control theory has resulted in significant research activity. A survey of the outcomes of this effort is presented.  ...  Acknowledgemenr-The authors are very grateful to the reviewers for their many valuable comments that greatly improved this work.  ...  The tools are mainly those of functional analysis, operator theory and analytic topology, which may be intimidating for a practitioner, but for the theoretician allows such things as the elegant unification  ... 
doi:10.1016/s1474-6670(17)47691-9 fatcat:sreewb52cndrliu4immw7pu6q4

Density-functional approaches to noncovalent interactions: A comparison of dispersion corrections (DFT-D), exchange-hole dipole moment (XDM) theory, and specialized functionals

Lori A. Burns, Álvaro Vázquez- Mayagoitia, Bobby G. Sumpter, C. David Sherrill
2011 Journal of Chemical Physics  
For overall results, M05-2X, B97-D3, and B970-D2 yield superior values in conjunction with aug-cc-pVDZ, for a mean absolute deviation of 0.41 -0.49 kcal/mol, and B3LYP-D3, B97-D3, ωB97X-D, and B2PLYP-D3  ...  evaluations of binding strength compiled for molecular complexes of diverse size and nature.  ...  by the basis employed for the respective level of theory.  ... 
doi:10.1063/1.3545971 pmid:21361527 fatcat:434pdlfu3jho3dagqjmuq23him

Limited sensitivity analysis of ARAIM availability for LPV-200 over Australia using real data

A. El-Mowafy, C. Yang
2016 Advances in Space Research  
The effect of reducing URA to 1 m, as a conservative future value, is first compared with the use of current broadcast URA values, where the same GPS data was processed in the two cases.  ...  GPS fault probabilities In ARAIM computations, overbounding of observation errors are classified into two levels: one for integrity evaluation and another affects continuity and accuracy.  ... 
doi:10.1016/j.asr.2015.10.046 fatcat:sj52pxl4rzcnnforutlaqhaa3m

Deep Q-learning: a robust control approach [article]

Balázs Varga, Balázs Kulcsár, Morteza Haghir Chehreghani
2022 arXiv   pre-print
We show the instability of learning and analyze the agent's behavior in frequency-domain. Then, we ensure convergence via robust controllers acting as dynamical rewards in the loss function.  ...  The role of the target network is overtaken by the control input, which also exploits the temporal dependency of samples (opposed to a randomized memory buffer).  ...  Meanwhile, control theory is seldom utilized to enhance the agent's training performance.  ... 
arXiv:2201.08610v1 fatcat:l3ub6jhwtjdz3o5hyns6ef57te

Robust Stability of a Class of Unstable Systems under Mixed Uncertainty

Rami A. Maher, Raghad Samir
2011 Journal of Control Science and Engineering  
For unstable plants, the priority of control goes to the stability of synthesis, which means to find a stabilizer controller.  ...  The problem was solved by a conservative method based on generalized Kharitonov's theorem and Nevanlinna-Pick's interpolation (NPI) technique.  ...  The applications of the Kharitonov theory to the analysis and synthesis of control systems have been introduced in many literatures such as [4] [5] [6] [7] [8] .  ... 
doi:10.1155/2011/970962 fatcat:3ybzcwxgf5cw7nit2aietemw6u

PALO: a probabilistic hill-climbing algorithm

Russell Greiner
1996 Artificial Intelligence  
Many learning systems search through a space of possible performance elements, seeking an element whose expected utility, over the distribution of problems, is high.  ...  These results suggest approaches to solving the utility problem from explanation-based learning, the multiple extension problem from nonmonotonic reasoning and the tractability/completeness tradeoff problem  ...  Acknowledgements This work began at the University of Toronto, where it was supported in part by the Institute for Robotics and Intelligent Systems and by an operating grant from the National Science and  ... 
doi:10.1016/0004-3702(95)00040-2 fatcat:gqjfb7nxibhslnlc4ib7jhjqjy

Set-valued observers and optimal disturbance rejection

J.S. Shamma, Kuang-Yang Tu
1999 IEEE Transactions on Automatic Control  
We then consider the utility of set-valued observers for disturbance rejection with output feedback and derive the following general separation structure.  ...  A set-valued observer (also called guaranteed state estimator) produces a set of possible states based on output measurements and models of exogenous signals.  ...  We then investigate the utility of set-valued observers for -induced norm optimal disturbance rejection.  ... 
doi:10.1109/9.746252 fatcat:pxjd5rjvl5eere2lkmvzwkqxcy

Paired overbounding and application to GPS augmentation

J. Rife, S. Pullen, B. Pervan, P. Enge
PLANS 2004. Position Location and Navigation Symposium (IEEE Cat. No.04CH37556)  
This paper introduces a theorem that guarantees a conservative error bound (overbound) in the position domain given similarly conservative overbounds for broadcast pseudorange statistics.  ...  States and Europe, the required inflation factor for broadcast sigma is only 1.18, even for biases as large as 10 cm for each satellite.  ...  The opinions discussed here are those of the authors and do not necessarily represent those of the FAA or other affiliated agencies.  ... 
doi:10.1109/plans.2004.1309027 fatcat:ljrrqaar7vh5hnyabk2vn5pvly
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