Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "Models" wg kryterium: Temat

  Lista filtrów
Wyrównaj
Wyświetlanie 1-15 z 58
Tytuł:
Modeling of gas consumption in the city
Autorzy:
Cieślik, T.
Metelska, K.
Powiązania:
https://bibliotekanauki.pl/articles/299233.pdf
Data publikacji:
2017
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
gas
gas consumption
models
Opis:
Based on the data collected over a two year time period, which included temperature, wind speed and gas consumption during the day, the effects of weather factors on gas consumption in the city have been established with the use of multiple regression. The impact of a particular month, day (dummy variable) or holiday of a year on the gas consumption has also been determined. The models of linear regression and artificial neural networks have been constructed for determining the gas consumption. An attempt has been made to find the best regression models and compare them to the neural network models with the use of mean absolute percentage error (MAPE).
Źródło:
AGH Drilling, Oil, Gas; 2017, 34, 2; 439-453
2299-4157
2300-7052
Pojawia się w:
AGH Drilling, Oil, Gas
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Machine learning models for predicting patients survival after liver transplantation
Autorzy:
Jarmulski, W.
Wieczorkowska, A.
Trzaska, M.
Ciszek, M.
Paczek, L.
Powiązania:
https://bibliotekanauki.pl/articles/305726.pdf
Data publikacji:
2018
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
machine learning
models interpretability
survival prediction
generalized additive models (GAM)
liver transplant
Opis:
In our work, we have built models predicting whether a patient will lose an organ after a liver transplant within a specified time horizon. We have used the observations of bilirubin and creatinine in the whole first year after the transplantation to derive predictors, capturing not only their static value but also their variability. Our models indeed have a predictive power that proves the value of incorporating variability of biochemical measurements, and it is the first contribution of our paper. As the second contribution we have identified that full-complexity models such as random forests and gradient boosting lack sufficient interpretability despite having the best predictive power, which is important in medicine. We have found that generalized additive models (GAM) provide the desired interpretability, and their predictive power is closer to the predictions of full-complexity models than to the predictions of simple linear models.
Źródło:
Computer Science; 2018, 19 (2); 223-239
1508-2806
2300-7036
Pojawia się w:
Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mean field and full field modelling of microstructure evolution and phase transformations during hot forming and cooling of low carbon steels
Autorzy:
Szeliga, Danuta
Bzowski, Krzysztof
Rauch, Łukasz
Kuziak, Roman
Pietrzyk, Maciej
Powiązania:
https://bibliotekanauki.pl/articles/29520270.pdf
Data publikacji:
2020
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
mean field models
full field models
finite element method
level set method
Opis:
The paper describes a critical comparison of mean field and full field approaches to modelling hot deformation/controlled cooling sequences for steels. Classification of the models, based on the balance between predictive capabilities and computing costs, is presented. Mean field models, which describe microstructure evolution and phase transformations were connected with thermomechanical finite element program and applied to simulation of the hot strip rolling process and cooling of tubes after hot rolling. Full field model described in the paper is a connection of the finite element (FE) and level set (LSM) methods. These methods were used to simulate heating/cooling sequence in the continuous annealing line. A suggestion to use a stochastic model as a bridge between mean field and full field approaches is made.
Źródło:
Computer Methods in Materials Science; 2020, 20, 3; 121-132
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Automatic bridge between BPMN models and UML activity diagrams based on graph transformation
Autorzy:
Rahmoune, Yasmina
Chaoui, Allaoua
Powiązania:
https://bibliotekanauki.pl/articles/27312904.pdf
Data publikacji:
2022
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
MDE
BPMN
business process models
UML-AD
meta-modeling
graph grammars
models transformation
AToM3
Opis:
Model-driven engineering (MDE) provides the available tools, concepts, and languages for creating and transforming models. One of the most important successes of MDE is model transformation; it permits the transformion of models that are used by one community to equivalent models that can be used by another one. Moreover, each community of developers has its own tools for verification, testing, and test-case generation. Hence, a developer of one community who moves to another community needs a transformation process from the second community to his/her own community and vice versa. Therefore, the target community can benefit from the expertise of the source one, and the developers do not begin from zero. In this context, we propose an automatic transformation in this paper for creating a bridge between the BPMN and UML communities. We propose an approach and a visual tool for the automatic transformation of BPMN models to UML activity diagrams (UML-AD). The proposed approach is based on meta-modeling and graph transformation and uses the AToM3 tool. Indeed, we were inspired by the OMG meta-models of BPMN and UML-AD and implemented versions of both meta-models using AToM3 . This latter one allows for the automatic generation of a visual-modeling tool for each proposed meta-model. Based on these two meta-models, we propose a graph grammar that is composed of 58 rules that perform the transformation process. The proposed approach is illustrated through three case studies.
Źródło:
Computer Science; 2022, 23 (3); 411--445
1508-2806
2300-7036
Pojawia się w:
Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Processes simulations with multiscale materials models using a dedicated interface
Autorzy:
Smyk, Grzegorz
Szeliga, Danuta
Powiązania:
https://bibliotekanauki.pl/articles/29520085.pdf
Data publikacji:
2021
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
multiscale modelling
material models
model integration
recrystallization
Opis:
The main goal of this work is the integration of in-house software with commercial numerical software based on the finite element method (FEM). The main idea is to develop a universal interface to perform process simulations with multiscale models. The interface allows the combination of external procedures with commercial software with minimum programmer’s work putting in integration. As an example, the model of material recrystallization of steel was implemented, added to the commercial application, and the software was tested for a process defined as a sequence of compression and cooling. The material model takes into consideration each type of recrystallization that occurs during a sequence of thermal and mechanical processing such as static recrystallization (SRX), dynamic recrystallization (DRX), and meta-dynamic recrystallization (MDRX). It allows the prediction of recrystallized volume fraction (X) and grain growth on each step of numerical simulation for each Gauss point in the computation domain. The presented multiscale model of process sequences not only allows to calculate microscale model parameters such as grain growth and recrystallized volume fraction, but also reflects the impact of the microscale model on macroscale parameters.
Źródło:
Computer Methods in Materials Science; 2021, 21, 4; 181-192
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Safety assessment of linear structures in areas at risk of large mining deformities
Ocena bezpieczeństwa konstrukcji liniowych w obszarach zagrożonych dużymi deformacjami górniczymi
Autorzy:
Fedorowicz, L.
Fedorowicz, J.
Powiązania:
https://bibliotekanauki.pl/articles/348747.pdf
Data publikacji:
2012
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
modele numeryczne
podłoże górnicze
modele stanu krytycznego
konstrukcje liniowe
numerical models
mining subsoil
critical state models
linear structures
Opis:
Safety assessment of the system 'structure-mining subsoil' results from the evaluation process of formation and areas with a range of changes in the ground state and local changes in stiffness of the subsoil. The paper presents, based on a constitutive model describing the behavior of soil Modified Cam-Clay (MCC), the following: - transmission mechanism of mining deformation from substrate to linear structure which cooperates with a layer (or layers) protecting its failure-free work, while proposing, - how to create description of protection layers behavior in a critical state model (MCC). Appropriate for the protected structure state of stresses and strains was obtained for the subsoil (with determined preconsolidation) and for the protective layer (with given parameters), by fulfilling the equation (1) with the determined critical strain eta/x = eta/0 promile. It is a condition accompanied by stress state, neglecting tension in the material of the protective layer (with the reserve of stresses provided for grids "strapping"). The thickness of critical layer (in which we do not allow tensioning) is determined due to preconsolidation state of the subsoil, and not by the state (stiffness) of the top layer. The predicted strain state of protective layer in the model does not provide any hazard for the work of the linear structure.
Ocena zagrożenia bezpieczeństwa układu budowla - podłoże górnicze wynika z oceny procesu powstawania i zasięgu obszarów zmian stanu gruntu oraz lokalnych zmian sztywności podłoża. W pracy przedstawiono, bazując na modelu konstytutywnego opisu zachowania gruntu Modyfied Cam-Clay (MCC): - mechanizm przekazywania deformacji pochodzenia górniczego z podłoża na konstrukcję liniową współpracującą z warstwą (lub warstwami) zabezpieczającymi jej bezawaryjną pracę, proponując równocześnie, - sposób tworzenia opisu pracy warstw zabezpieczających w modelu stanu krytycznego (MCC). Właściwy dla zabezpieczanej konstrukcji stan naprężeń i odkształceń uzyskano dla podłoża (o przyjętej prekonsolidacji) i warstwie zabezpieczającej (o podanych w pracy parametrach), przy spełnieniu równania (1) przy określonym odkształceniu krytycznym eta/x = eta/0 promile. Stanowi temu towarzyszy stan naprężenia, który nie wywołuje rozciągania w materiale warstwy zabezpieczającej (przy niewielkiej jeszcze rezerwie naprężeń przewidzianych jako "spinające" siatkę). Istotnym wnioskiem jest stwierdzenie, że o miąższości warstwy krytycznej (w której nie dopuszczamy rozciągania) decyduje stan prekonsolidacji podłoża gruntowego, a nie stan (sztywność) warstwy przypowierzchniowej. Przewidywany w modelu stan odkształcenia warstwy zabezpieczającej jest stanem bezpiecznym dla pracy konstrukcji.
Źródło:
AGH Journal of Mining and Geoengineering; 2012, 36, 1; 145-153
1732-6702
Pojawia się w:
AGH Journal of Mining and Geoengineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Price duration versus trading volume in high-frequency data for selected DAX companies
Autorzy:
Gurgul, H.
Syrek, R.
Mitterer, C.
Powiązania:
https://bibliotekanauki.pl/articles/1201243.pdf
Data publikacji:
2016
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
Frankfurt Stock Exchange
intraday data
duration models
copulas
Opis:
The main goal of this paper is to gain insights into the dependence structure between the duration and trading volume of selected stocks listed on the Frankfurt Stock Exchange. We demonstrate the usefulness of the copula function to describe the dependence of specific unevenly spaced time series. The properties of the time series of price durations and trading volumes under study are in line with common observations from other empirical studies. We observe clustering, overdispersion, and diurnality. For most of the stocks, the seminal model (linear parametrization with exponential or Weibull distribution) can be replaced by a logarithmic specification with more-flexible conditional distributions. The price duration and trading volume associated with this duration exhibit dependence in the tails of distribution. We may conclude that high cumulative trading volumes are associated with long duration. However, changes of price over short times are related to low cumulative volume.
Źródło:
Managerial Economics; 2016, 17, 2; 241-260
1898-1143
Pojawia się w:
Managerial Economics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical simulation of drilling fluid flow in annular the space of the borehole
Autorzy:
Kowalska-Kubsik, I.
Powiązania:
https://bibliotekanauki.pl/articles/299058.pdf
Data publikacji:
2015
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
numerical simulation
fluid flow
drilling fluids
rheological models
Opis:
This paper presents the numerical results of a numerical analysis of drilling fluid flow through annular space in the borehole. The analysis used the Herschel–Bulkley rheological fluid model. The obtained results of the analysis for three cases with variable geometry. Variable geometry is associated with a larger diameter drill in the joints of drill pipes, and consequently, with reduced flow cross-section. A comparison of pressure values at the end of the analyzed examples showed that in the example of a simple drill pipe without joints, pressure values were 30% higher than in the case, which takes into account changes in the geometry of the joints.
Źródło:
AGH Drilling, Oil, Gas; 2015, 32, 4; 775-783
2299-4157
2300-7052
Pojawia się w:
AGH Drilling, Oil, Gas
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Using well testing to confirm the suspected reservoir model by seismic investigations
Zastosowanie testów otworowych do potwierdzenia modelu złożowego stworzonego przy użyciu badań sejsmicznych
Autorzy:
Tataru, A.
Stefanescu, D. P.
Simescu, B.
Powiązania:
https://bibliotekanauki.pl/articles/300337.pdf
Data publikacji:
2009
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
modelowanie złóż
badania sejsmiczne
reservoir models
seismic investigations
Opis:
The activity of seismic surveys is very complex and has the purpose to investigate the underground, in order to discover productive geological structures and various relations among the already known structures. More often, lately, there are looked for subtle traps in the areas with complicated geology, fact that requires more attention in the projection and execution of acquisition works, as well as the processing and interpretation of the gathered information. An area intensively researched lately is the Eastern area of Romania, a very troubled area from a tectonic point of view, with many structural traps and very many faults. In this region, our company emphasized several hydrocarbon accumulations of lenticular form.
Badania sejsmiczne, wykonywane w sposób kompleksowy, mają na celu poznanie podłoża gruntowego, rozpoznania skał perspektywicznych oraz zależności pomiędzy już poznanymi strukturami. W ostatnich latach coraz częściej badania sejsmiczne wykorzystywane są do lokalizowania trudno dostępnych pułapek geologicznych znajdujących się w skomplikowanych strukturach geologicznych. Wymaga to bardzo dokładnego wykonania badań oraz odwzorowania budowy geologicznej, jak również szczegółowej interpretacji zebranych informacji. Artykuł zawiera wyniki badań sejsmicznych przeprowadzonych na terenie wschodniej Rumuni. Z tektonicznego punktu widzenia region ten cechuje się bardzo trudną budową geologiczną z wieloma strukturami tektonicznymi o charakterze pułapek geologicznych. W wyniku przeprowadzonych badań nasza Firma odkryła na tym terenie kilkanaście złóż węglowodorów.
Źródło:
Wiertnictwo, Nafta, Gaz; 2009, 26, 1--2; 391-396
1507-0042
Pojawia się w:
Wiertnictwo, Nafta, Gaz
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A workflow-oriented approach to Propagation Models in Heliophysics
Autorzy:
Pierantoni, G.
Carley, E.
Byrne, J.
Perez-Suarez, D.
Gallagher, P. T.
Powiązania:
https://bibliotekanauki.pl/articles/305701.pdf
Data publikacji:
2014
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
heliophysics
workflow
TAVERNA
Coronal Mass Ejection
propagation models
Opis:
The Sun is responsible for the eruption of billions of tons of plasma and the generation of near light-speed particles that propagate throughout the solar system and beyond. If directed towards Earth, these events can be damaging to our tecnological infrastructure. Hence there is an effort to understand the cause of the eruptive events and how they propagate from Sun to Earth. However, the physics governing their propagation is not well understood, so there is a need to develop a theoretical description of their propagation, known as a Propagation Model, in order to predict when they may impact Earth. It is often difficult to define a single propagation model that correctly describes the physics of solar eruptive events, and even more difficult to implement models capable of catering for all these complexities and to validate them using real observational data. In this paper, we envisage that workflows offer both a theoretical and practical framework for a novel approach to propagation models. We define a mathematical framework that aims at encompassing the different modalities with which workflows can be used, and provide a set of generic building blocks written in the TAVERNA workflow language that users can use to build their own propagation models. Finally we test both the theoretical model and the composite building blocks of the workflow with a real Science Use Case that was discussed during the 4th CDAW (Coordinated Data Analysis Workshop) event held by the HELIO project. We show that generic workflow building blocks can be used to construct a propagation model that succesfully describes the transit of solar eruptive events toward Earth and predict a correct Earth-impact time.
Źródło:
Computer Science; 2014, 15 (3); 271-291
1508-2806
2300-7036
Pojawia się w:
Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of anti-sedimentation agents on the technological parameters of cement slurry
Autorzy:
Kremieniewski, M.
Rzepka, M.
Stryczek, S.
Wiśniowski, R.
Powiązania:
https://bibliotekanauki.pl/articles/298824.pdf
Data publikacji:
2017
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
sealing slurries
rheological properties
rheological models
superplastifiers
cement slurries
Opis:
Recently, the intensifying development of shale drilling has contributed to the more numerous realization of directional and horizontal boreholes. Moreover, such boreholes are more advantageous as they provide about 4 times higher production than in their vertical counterparts, give access to poorly drained areas, or production of already developed reservoir, where only a new borehole has to be introduced to the network. It should be stressed that the sealing of the casing columns is a challenge because of the restrictions set before drilling fluids used for sealing horizontal boreholes. Slurries play a special role while sealing horizontal boreholes and therefore their technological parameters and density should be adjusted to the geological-reservoir conditions. At the stage of designing slurries for sealing horizontal boreholes, the most important parameters are: sedimentation stability, zero water settling water settling and low filtration. Meeting these requirements was possible by selecting proper admixtures and additives, which in turn, is a guarantee of the uniform and homogeneous structure of fresh and hardened cement slurry. Thus formed cement sheath of bounded slurry should be impervious to gas and have good mechanical properties over the length of the sealing without any trends of anisotropy of the medium in particular points. Modification and designing specialist recipes for definite technological conditions lie, among others, in choosing proper slurry additives and admixtures. However, obtaining appropriate parameters for given conditions may be connected with a change of other parameters deciding about the efficiency of the sealing of a given horizon. Therefore while working out a new recipe for a slurry, the designer should account for the analytical results and influence of the applied agents on all of the parameters of slurry. This is the subject matter of the paper.
Źródło:
AGH Drilling, Oil, Gas; 2017, 34, 4; 945-957
2299-4157
2300-7052
Pojawia się w:
AGH Drilling, Oil, Gas
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The verification of the estimation of transport and sorption parameters in the MATLAB environment. A column test
Autorzy:
Okońska, M.
Kaczmarek, M.
Małoszewski, P.
Marciniak, M.
Powiązania:
https://bibliotekanauki.pl/articles/184718.pdf
Data publikacji:
2017
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
column tests
sorption models
parameters
numerical solution
optimization
MATLAB
Opis:
Mathematical modelling of the migration of pollutants in the groundwater environment requires knowledge of the values of transport and sorption parameters. The aim of this study was 1) to determine the values of advection, dispersion and sorption parameters of selected tracers that are transported through a porous medium, and 2) to verify the applied parameters estimation procedure. The authors examined the migration of a solution containing conservative and reactive tracers (chloride, nitrate, lithium and ammonium ions) through a sample of medium sand. The soil sample for the column test was taken from an aquifer near the Tursko groundwater intake (Wielkopolska province, Poland). The parameter estimation procedure, conducted in the MATLAB environment, included the numerical solution of the differential equations of transport and sorption, and the application of the numerical optimization method. During the identification, the authors tested twelve mathematical models including the advection-dispersion model, as well as single and hybrid (i.e. two-site) sorption models. The authors made a comparison of parameter values obtained by means of the global and local optimization method. The fitting quality was assessed by calculating the root mean square error RMSE and correlation coefficient r. As a result of the research, the authors determined the values of the advection-dispersion parameters: hydraulic conductivity k, effective porosity n e, and longitudinal dispersivity α. The authors found out that the nature oflithium ions migration is best captured by the single sorption model (equilibrium sorption), whereas the nature of ammonium ions migration is by the hybrid model with irreversible sorption. Lithium ions on the tested soil revealed low sorption intensity, ammonium ions showed medium intensity, while nitrate ions were transported at the same rate as chloride ions, exhibiting no retardation. The verification of parameter estimation in the MATLAB environment was carried out by comparing it against the alternative, well-known and often tested method, based on analytical solutions of the transport and sorption equation, combined with optimization within the FIELD and KLUTE-STEP programmes.
Źródło:
Geology, Geophysics and Environment; 2017, 43, 3; 213-227
2299-8004
2353-0790
Pojawia się w:
Geology, Geophysics and Environment
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Extending the sheba propagatio model to reduce parameter-related uncertainties
Autorzy:
Pierantoni, G.
Coghlan, B.
Kenny, E.
Gallagher, P.
Perez-Suarez, D.
Powiązania:
https://bibliotekanauki.pl/articles/305331.pdf
Data publikacji:
2013
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
heliophysics
HELIO
SCI-BUS
distributed computation infrastructure
propagation models
Opis:
Heliophysics is the branch of physics that investigates the interactions and correlation of different events across the Solar System. The mathematical models that describe and predict how physical events move across the solar system (ie. Propagation Models ) are of great relevance. These models depend on parameters that users must set, hence the ability to correctly set the values is key to reliable simulations. Traditionally, parameter values can be inferred from data either at the source (the Sun) or arrival point (the target) or can be extrapolated from common knowledge of the event under investigation. Another way of setting parameters for Propagation Models is proposed here: instead of guessing a priori parameters from scientific data or common knowledge, the model is executed as a parameter-sweep job and selects a posteriori the parameters that yield results most compatible with the event data. In either case ( a priori and a posteriori ), the correct use of Propagation Models requires information to either select the parameters, validate the results, or both. In order to do so, it is necessary to access sources of information. For this task, the HELIO project proves very effective as it offers the most comprehensive integrated information system in this domain and provides access and coordination to services to mine and analyze data. HELIO also provides a Propagation Model called SHEBA, the extension of which is currently being developed within the SCI-BUS project (a coordinated effort for the development of a framework capable of offering to science gateways seamless access to major computing and data infrastructures).
Źródło:
Computer Science; 2013, 14 (2); 253-272
1508-2806
2300-7036
Pojawia się w:
Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enhancements of Fuzzy Q-Learning algorithm
Rozszerzenia algorytmu Fuzzy Q-Learning
Autorzy:
Głowaty, G.
Powiązania:
https://bibliotekanauki.pl/articles/305545.pdf
Data publikacji:
2005
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
modele rozmyte
uczenie ze wzmocnieniem
Q-Learning
automatyczne tworzenie modeli rozmytych
fuzzy models
reinforcement learning
Q-learning
automatic generation of fuzzy models
Opis:
Fuzzy Q-Learning algorithm combines reinforcement learning techniques with fuzzy modelling. It provides a flexible solution for automatic discovery of rules for fuzzy systems in the process of reinforcement learning. In this paper we propose several enhancements to the original algorithm to make it more performant and more suitable for problems with continuous-input continuous-output space. Presented improvements involve generalization of the set of possible rule conclusions. The aim is not only to automatically discover an appropriate rule-conclusions assignment, but also to automatically define the actual conclusions set given the all possible rules conclusions. To improve algorithm performance when dealing with environments with inertness, a special rule selection policy is proposed.
Algorytm Fuzzy Q-Learning pozwala na automatyczny dobór reguł systemu rozmytego z użyciem technik uczenia ze wzmocnieniem. W niniejszym artykule zaproponowana została zmodyfikowana wersja oryginalnego algorytmu. Charakteryzuje się ona lepszą wydajnością działania w systemach z ciągłymi przestrzeniami wejść i wyjść. Algorytm rozszerzono o możliwość automatycznego tworzenia zbioru potencjalnych konkluzji reguł z podanego zbioru wszystkich możliwych konkluzji. Zaproponowano także nową procedurę wyboru reguł dla polepszenia prędkości działania w systemach z bezwładnością.
Źródło:
Computer Science; 2005, 7; 77-87
1508-2806
2300-7036
Pojawia się w:
Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Four positive periodic solutions of a discrete time Lotka-Volterra competitive system with harvesting terms
Autorzy:
Liu, X.
Ren, Y.
Li, Y.
Powiązania:
https://bibliotekanauki.pl/articles/254985.pdf
Data publikacji:
2011
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
discrete systems
Lotka-Volterra competitive models
coincidence degree
harvesting terms
Opis:
In this paper, by using Mawhin's continuation theorem of coincidence degree theory, we establish the existence of at least four positive periodic solutions for a discrete time Lotka-Volterra competitive system with harvesting terms. An example is given to illustrate the effectiveness of our results.
Źródło:
Opuscula Mathematica; 2011, 31, 2; 257-267
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 58

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies