Browsing by Author "Schaefer, Robert"
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Item type:Thesis, Access status: Restricted , Adaptive finite element method solver with logarithmic cost(Data obrony: 2013-09-18) Woźniak, Maciej
Wydział Informatyki, Elektroniki i TelekomunikacjiItem type:Thesis, Access status: Restricted , Adaptive solver for non-stationary problems(Data obrony: 2014-09-17) Goik, Damian
Wydział Informatyki, Elektroniki i TelekomunikacjiItem type:Thesis, Access status: Restricted , Algorithms for Gaining Advantage in Parliamentary Elections(Data obrony: 2018-09-12) Furdyna, Michał
Wydział Informatyki, Elektroniki i TelekomunikacjiItem type:Thesis, Access status: Restricted , Data adaptation in HANDY economy-ideology model(Data obrony: 2019-03-07) Sendera, Marcin
Wydział Informatyki, Elektroniki i TelekomunikacjiItem type:Thesis, Access status: Restricted , Estymacja pozy 6D obiektów w oparciu o konwolucyjne sieci neuronowe(Data obrony: 2019-07-12) Onieszczuk, Konrad
Wydział Informatyki, Elektroniki i TelekomunikacjiItem type:Thesis, Access status: Restricted , Fast isogeometric L2-projection solver for non-linear flows in non-homogenous media(Data obrony: 2015-07-22) Łoś, Marcin
Wydział Informatyki, Elektroniki i TelekomunikacjiItem type:Thesis, Access status: Restricted , Generacja interfejsu użytkownika na podstawie schematu XSD(Data obrony: 2010-09-30) Jagielski, Piotr
Wydział Elektrotechniki, Automatyki, Informatyki i ElektronikiItem type:Thesis, Access status: Restricted , Hierarchic evolutionary computation with stable mutation(Data obrony: 2015-09-30) Obuchowicz, Adam
Wydział Informatyki, Elektroniki i TelekomunikacjiItem type:Article, Access status: Open Access , HP-HGS strategy for inverse AC/DC resistivity logging measurement simulations(Wydawnictwa AGH, 2013) Gajda-Zagórska, Ewa; Paszyński, Maciej; Schaefer, Robert; Pardo, DavidIn this paper, we present resistivity-logging-measurement simulation with the use of two types of borehole logging devices: those which operate with zero frequency (direct current, DC) and those with higher frequencies (alternate current, AC). We perform simulations of 3D resistivity measurements in deviated wells, with a sharp angle between the borehole and formation layers. We introduce a hierarchical adaptive genetic strategy hp ? HGS interfaced with an adaptive finite element method. We apply a strategy for the solution of the inverse problem, where we identify the resistivities of the formation layers based on a given measurement. We test the strategy on both direct and alternate current cases.Item type:Thesis, Access status: Restricted , Identification of low sensitivity regions for inverse problems solutions(Data obrony: 2016-06-30) Sawicki, Jakub
Wydział Informatyki, Elektroniki i TelekomunikacjiItem type:Thesis, Access status: Restricted , Improving population-based algorithms used in Global Optimization with Fitness Deterioration techniques(Data obrony: 2012-01-04) Wolny, Adrian
Wydział Elektrotechniki, Automatyki, Informatyki i ElektronikiItem type:Thesis, Access status: Restricted , Interfejs zarządzający hierarchiczną strategią genetyczną FHGS(Data obrony: 2012-10-26) Pieczka, Bartłomiej
Wydział Elektrotechniki, Automatyki, Informatyki i ElektronikiItem type:Article, Access status: Open Access , Misfit landforms imposed by ill-conditioned inverse parametric problems(Wydawnictwa AGH, 2018) Łoś, Marcin Mateusz; Smołka, Maciej; Schaefer, Robert; Sawicki, JakubIn this paper, we put forward a new topological taxonomy that allows us to distinguish and separate multiple solutions to ill-conditioned parametric inverse problems appearing in engineering, geophysics, medicine, etc. This taxonomy distinguishes the areas of insensitivity to parameters called the landforms of the misfit landscape, be it around minima (lowlands), maxima (uplands), or stationary points (shelves). We have proven their important separability and completeness conditions. In particular, lowlands, uplands, and shelves are pairwise disjoint, and there are no other subsets of the positive measure in the admissible domain on which the misfit function takes a constant value. The topological taxonomy is related to the second, »local« one, which characterizes the types of ill-conditioning of the particular solutions. We hope that the proposed results will be helpful for a better and more precise formulation of ill-conditioned inverse problems and for selecting and profiling complex optimization strategies used in solving these problems.Item type:Article, Access status: Open Access , On the computational cost and complexity of stochastic inverse solvers(Wydawnictwa AGH, 2016) Faliszewski, Piotr; Smołka, Maciej; Schaefer, Robert; Paszyński, MaciejThe goal of this paper is to provide a starting point for investigations into a mainly underdeveloped area of research regarding the computational cost analysis of complex stochastic strategies for solving parametric inverse problems. This area has two main components: solving global optimization problems and solving forward problems (to evaluate the misfit function that we try to minimize). For the first component, we pay particular attention to genetic algorithms with heuristics and to multi-deme algorithms that can be modeled as ergodic Markov chains. We recall a simple method for evaluating the first hitting time for the single-deme algorithm and we extend it to the case of HGS, a multi-deme hierarchic strategy. We focus on the case in which at least the demes in the leaves are well tuned. Finally, we also express the problems of finding local and global optima in terms of a classic complexity theory. We formulate the natural result that finding a local optimum of a function is an NP-complete task, and we argue that finding a global optimum is a much harder, DP-complete, task. Furthermore, we argue that finding all global optima is, possibly, even harder (#P-hard) task. Regarding the second component of solving parametric inverse problems (i.e., regarding the forward problem solvers), we discuss the computational cost of hp-adaptive Finite Element solvers and their rates of convergence with respect to the increasing number of degrees of freedom. The presented results provide a useful taxonomy of problems and methods of studying the computational cost and complexity of various strategies for solving inverse parametric problems. Yet, we stress that our goal was not to deliver detailed evaluations for particular algorithms applied to particular inverse problems, but rather to try to identify possible ways of obtaining such results.Item type:Doctoral Dissertation, Access status: Metadata only , Opracowanie i implementacja równoległych algorytmów adaptacyjnej metody elementów skończonych na sieci stacji roboczych i komputerze wieloprocesorowym(Data obrony: 2000) Płażek, Joanna
Wydział Elektrotechniki, Automatyki, Informatyki i ElektronikiItem type:Thesis, Access status: Restricted , Parallel algorith for integrating three-dimensional B-Spline functions with shared memory machines(Data obrony: 2020-09-29) Bukowska, Anna
Wydział Informatyki, Elektroniki i TelekomunikacjiItem type:Thesis, Access status: Restricted , Parser wstępujący dla gramatyk grafowych klasy edNLC(Data obrony: 2013-07-09) Flasińska, Zofia
Wydział Informatyki, Elektroniki i TelekomunikacjiItem type:Thesis, Access status: Restricted , Równoległa implementacja solwera wielofrontalnego bazującego na gramatykach grafowych przy użyciu systemu Galois(Data obrony: 2014-06-17) Jopek, Konrad
Wydział Informatyki, Elektroniki i TelekomunikacjiItem type:Thesis, Access status: Restricted , Socjo-kognitywne systemy mrówkowe w problemach optymalizacji dyskretnej(Data obrony: 2016-07-14) Świderska, Ewelina; Łasisz, Jakub
Wydział Informatyki, Elektroniki i TelekomunikacjiItem type:Thesis, Access status: Restricted , Socjo-kognitywne systemy mrówkowe w problemach optymalizacji dyskretnej(Data obrony: 2016-07-14) Łasisz, Jakub; Świderska, Ewelina
Wydział Informatyki, Elektroniki i Telekomunikacji