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Artigo

Marius L. Tomescu, Ștefan Preitl, Radu‐Emil Precup, József K. Tar,

This paper presents a new stability analysis method for nonlinear processes with Takagi-Sugeno (T-S) fuzzy logic controllers (FLCs). The design of the FLCs is based on heuristic fuzzy rules. The stability analysis of these fuzzy control systems is performed using LaSalle's invariant set principle with non-quadratic Lyapunov candidate function. This paper proves that if the derivative of Lyapunov function is negative semi-definite in the active region of each fuzzy rule, then the overall system will ...

Tópico(s): Stability and Control of Uncertain Systems

2007 - Óbuda University | Acta Polytechnica Hungarica

Artigo Revisado por pares

Shih-Yu Pan, Bieng-Zih Hsieh, Ming-Tar Lu, Zsay-Shing Lin,

The purpose of this study was to identify the formation interfaces from geophysical well log data using the wavelet transform, and a combination of the wavelet transform and the Fourier transform methods. In the wavelet transform method, the identification of formation interfaces is based on the wavelet coefficients from the wavelet transform of spontaneous potential (SP) log and gamma ray (GR) log data. In the combination of the wavelet transform and the Fourier transform methods, the wavelet transform, ...

Tópico(s): NMR spectroscopy and applications

2007 - Elsevier BV | Computers & Geosciences

Artigo Revisado por pares

Radu‐Emil Precup, Ștefan Preitl, Imre J. Rudas, Marius L. Tomescu, József K. Tar,

This paper proposes a new fuzzy control solution employing 2-DOF proportional-integral-fuzzy controllers dedicated to a class of servo systems. The controlled plants in these systems, widely used in mechatronics applications, can be characterized by second-order dynamics with integral type. The original design method suggested here starts with linear design results in terms of the extended symmetrical optimum method accompanied by an iterative feedback tuning (IFT) algorithm. Next, these results ...

Tópico(s): Fuzzy Logic and Control Systems

2008 - Institute of Electrical and Electronics Engineers | IEEE/ASME Transactions on Mechatronics

Artigo Revisado por pares

Károly Tar,

The article, which is a segment of a complex wind energy examination, uses statistical methods to analyze the time series of monthly average wind speed in the period between 1991 and 2000 measured on seven Hungarian meteorological stations. Empirical distribution of measured monthly average wind speeds is approximated by theoretical distributions to claim that certain distributions are universal, i.e. independent of orography. We used one of them, the Weibull distribution, to generate the distribution ...

Tópico(s): Wind and Air Flow Studies

2007 - Elsevier BV | Renewable and Sustainable Energy Reviews

Artigo Revisado por pares

Károly Tar, S. Szegedi,

Potential wind power for a given period (e.g. a day) can be determined from wind speed data measured in certain hours of a period. Obviously, the sum of the cubes of wind speeds measured depends on the number of measurements. This dependence can be reduced in two ways: determining the average and the relative wind energy for a given time within a given period. The method of sliding averages uses both. Applying this method a given hourly average wind speed cube of a day is estimated on the basis of ...

Tópico(s): Solar Radiation and Photovoltaics

2010 - Elsevier BV | Renewable Energy

Artigo Revisado por pares

Claudiu Pozna, Fritz Troester, Radu‐Emil Precup, József K. Tar, Ștefan Preitl,

The paper suggests a new mathematical construction for the potential field used in the design of obstacle avoiding trajectories. The main benefits of the proposed construction are the quickness of minimum computation and the compensation for the main drawbacks specific to the "traditional approaches" belonging to the potential field method in general. The potential field definition and its minimum computation concept are presented. Next the concept is included in a design method for obstacle avoiding ...

Tópico(s): Control and Dynamics of Mobile Robots

2008 - Elsevier BV | Mathematics and Computers in Simulation

Artigo Revisado por pares

Péter Tar, Bálint Stágel, István Maros,

Tópico(s): Metaheuristic Optimization Algorithms Research

2016 - Springer Science+Business Media | Central European Journal of Operations Research

Artigo

Arvo Tars,

A good deal of work has been done over the years trying to demonstrate the feasibility or superiority of automatic indexing techniques. (1--8) Most of these techniques are designed for natural language systems, i. e., systems which have an uncontrolled vocabulary. While they incorporate many desirable features, they also have some disadvantages.

Tópico(s): Natural Language Processing Techniques

1976 - Association for Computing Machinery | ACM SIGIR Forum

Artigo Acesso aberto

Barry Boehm,

"No scene from prehistory is quite so vivid as that of the mortal struggles of great beasts in the tar pits… Large system programming has over the past decade been such a tar pit, and many great and powerful beasts have thrashed violently in it…"Everyone seems to have been surprised by the stickiness of the problem, and it is hard to discern the nature of it. But we must try to understand it if we are to solve it."Fred Brooks, 1975Several recent books and reports have confirmed ...

Tópico(s): Advanced Software Engineering Methodologies

1999 - Association for Computing Machinery | ACM SIGSOFT Software Engineering Notes

Artigo Revisado por pares

Ákos Tar, György Cserey,

In this paper, a method of detecting object outlines and creating surface traces using a low-cost distance measurement array of infrared light-emitting diode (LED)-photodiode pairs is demonstrated. For each active LED, the light level on the corresponding photodiode may be measured, generating an image of distance values whose pixel resolution is limited to the spacing between LED-photodiode pairs. Moreover, using several photodiodes to detect the reflected light from each LED, lateral resolution ...

Tópico(s): Optical measurement and interference techniques

2011 - IEEE Sensors Council | IEEE Sensors Journal

Artigo Revisado por pares

Claudiu Pozna, Radu‐Emil Precup, József K. Tar, Igor Škrjanc, Ștefan Preitl,

This paper suggests an original heuristic modelling algorithm expressed in terms of homogenous combinations of the classical system dynamics and the Bayesian degree of truth employed in modelling. The main benefits of the proposed approach compared to classical modelling are the increased transparency and alleviated computational time. Two case studies, dealing with a mobile robot and an unforced pendulum system, are included to exemplify and test the theoretical results. One of the case studies ...

Tópico(s): Advanced Data Processing Techniques

2009 - Elsevier BV | Knowledge-Based Systems

Artigo Acesso aberto Revisado por pares

Andrea K. Thomer,

Abstract Scientifically significant sites are the source of, and long‐term repository for, considerable amounts of data—particularly in the natural sciences. However, the unique data practices of the researchers and resource managers at these sites have been relatively understudied. Through case studies of two scientifically significant sites (the hot springs at Yellowstone National Park and the fossil deposits at the La Brea Tar Pits), I developed rich descriptions of site‐based research and data ...

Tópico(s): Scientific Computing and Data Management

2022 - Wiley | Journal of the Association for Information Science and Technology

Artigo Acesso aberto Revisado por pares

Hemza Redjimi, József K. Tar,

Using the interpolation/extrapolation skills of the core function of an iterative adaptive controller, a structurally simple single essential layer neural network-based topological structure is suggested with fast and explicit single-step teaching and data-retrieving abilities. Its operation does not assume massive parallelism, therefore it easily can be simulated by simple sequential program codes not needing sophisticated data synchronization mechanisms. It seems to be advantageous in approximate ...

Tópico(s): Model Reduction and Neural Networks

2021 - Multidisciplinary Digital Publishing Institute | Machines

Artigo Revisado por pares

Radu‐Emil Precup, Ștefan Preitl, Emil M. Petriu, József K. Tar, Marius L. Tomescu, Claudiu Pozna,

This paper presents a new framework for the design of generic two-degree-of-freedom (2-DOF), linear and fuzzy, controllers dedicated to a class of integral processes specific to servo systems. The first part of the paper presents four 2-DOF linear PI controller structures that are designed using the Extended Symmetrical Optimum method to ensure the desired overshoot and settling time. The second part of the paper presents an original design method for 2-DOF Takagi–Sugeno PI-fuzzy controllers based ...

Tópico(s): Advanced Control Systems Design

2009 - Elsevier BV | Journal of the Franklin Institute

Artigo Revisado por pares

Carlos Amen-Chen, Hooshang Pakdel, Christian Roy,

Tópico(s): Adsorption, diffusion, and thermodynamic properties of materials

1997 - Elsevier BV | Biomass and Bioenergy

Artigo Revisado por pares

O.H. Oren,

Tópico(s): Marine and environmental studies

1970 - Elsevier BV | Marine Pollution Bulletin

Artigo Revisado por pares

Michael C. Mulder,

The Model Curricula Subcommittee of the IEEE Computer Society Education Committee was formed some 16 months ago to develop an IEEE Computer Society-sanctioned four-year curriculum in computer science and engineering to be used by colleges and universities beginning instruction in this discipline, and by many institutions with existing programs. To date, the subcommittee has concerned itself with the four-year BS degree in computer science and engineering. The subcommittee members are Michael C. ...

Tópico(s): Information Systems Education and Curriculum Development

1975 - IEEE Computer Society | Computer

Artigo Revisado por pares

Éva Tar,

This study investigates the developmental patterns of acquisition of word-initial (WI) /r/-clusters in children speaking Hungarian, typically developing (TD) or with protracted phonological development (PPD). Comparison data were also analysed for WI singleton /r/ and /l/. Participants were 191 children (aged 3;0-5;11) divided into three age groups (3, 4, 5 years), and further subdivided into TD and PPD subgroups on the basis of Whole Word Match scores (WWM). Acoustic analyses of perceptually accurate clusters ...

Tópico(s): Speech Recognition and Synthesis

2017 - Taylor & Francis | Clinical Linguistics & Phonetics

Capítulo de livro

Wojciech Kowalczyk, Krzysztof Kozłowski, József K. Tar,

IntroductionCooperative robotics is a currently intensively investigated area of science. Great development in technology has attracted research interest in many countries on this subject. It is caused by availability of reliable, efficient and inexpensive components of mobile robots. In addition, some tasks can be executed more efficiently using multiple simple, low-cost mobile robots instead of one bigger robot. Multi-robot systems have a wide range of applications: service robots, transportation, ...

Tópico(s): Modular Robots and Swarm Intelligence

2009 - Springer Science+Business Media | Lecture notes in control and information sciences

Artigo Acesso aberto Revisado por pares

FK St. Charles, George R. Krautter, Derek C. Mariner,

The purpose of this study was to determine the effect of different tar yield cigarette brands on the post-puff inhalation/exhalation depth and duration for established smokers of the brands. The study was conducted with 74 established smokers of 1-17 mg Federal Trade Commission (FTC) tar products. The subjects were participating in a five-day inpatient clinical biomarker study during which time they were allowed to smoke their own brand of cigarette whenever they wished. On two separate days, the ...

Tópico(s): Advanced Data Compression Techniques

2009 - Taylor & Francis | Inhalation Toxicology

Artigo Revisado por pares

Fabio H. Nieto, Hanwen Zhang, Wen Li,

One way that has been used for identifying and estimating threshold autoregressive (TAR) models for nonlinear time series follows the Markov chain Monte Carlo (MCMC) approach via the Gibbs sampler. This route has major computational difficulties, specifically, in getting convergence to the parameter distributions. In this article, a new procedure for identifying a TAR model and for estimating its parameters is developed by following the reversible jump MCMC procedure. It is found that the proposed ...

Tópico(s): Statistical Methods and Inference

2012 - Taylor & Francis | Communications in Statistics - Simulation and Computation

Artigo Acesso aberto Revisado por pares

Tiina Suopajärvi,

In a smart city, technologies are designed to assist people in their everyday lives, like in intelligent homes, public transportation, and e-services. However, this can lead to new kind of marginalisation if people do not fit into the idea of smart citizen. In this article, I consider how the smart city ideology of Oulu in northern Finland becomes lived in the everyday practices of senior citizens; and how they sense themselves as “smart citizens.” Through generating ethnographic composition of ICT- ...

Tópico(s): Context-Aware Activity Recognition Systems

2018 - | Ethnologia Fennica

Artigo Revisado por pares

J. du Rouchet,

During secondary migration, the tendency towards a thermodynamic minimization of the hydrocarbon‐water interfacial energy can result in the confinement of petroleum in open fractures and coarser pores, in spite of the repeated conversion of gravitational energy into interfacial energy. A discussion of lithological influences leads to the prediction that migration in granular porosity is likely to end in trapping or dispersal, whereas migration in brittle, compact formations, which are little fractured, ...

Tópico(s): Atmospheric and Environmental Gas Dynamics

1984 - Wiley | Journal of Petroleum Geology

Artigo Revisado por pares

Thomas Lombardo, Cecelia Jo Davis, Donald M. Prue,

Trained raters can reliably identify vent-blocking in ultralight cigarettes based on tar stain patterns, yet detection of this phenomenon has not been previously studied in light cigarettes. This study was conducted to extend the research on vent-blocking in ultralight cigarettes to the much more popular light cigarettes. We wanted to find out if individuals could discriminate among stain patterns on cigarette butts with unblocked (0%), partially blocked (50%), and fully blocked (100%) vents using ...

Tópico(s): Image and Signal Denoising Methods

1983 - Elsevier BV | Addictive Behaviors

Artigo Acesso aberto Revisado por pares

Vernon K. Krieble, William F. Seyer,

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA CHEMICAL INVESTIGATION OF THE ASPHALT IN THE TAR SANDS OF NORTHERN ALBERTA.Vernon K. Krieble and William F. SeyerCite this: J. Am. Chem. Soc. 1921, 43, 6, 1337–1349Publication Date (Print):June 1, 1921Publication History Published online1 May 2002Published inissue 1 June 1921https://pubs.acs.org/doi/10.1021/ja01439a016https://doi.org/10.1021/ja01439a016research-articleACS PublicationsRequest reuse permissionsArticle Views58Altmetric-Citations3LEARN ABOUT ...

Tópico(s): Geochemistry and Geologic Mapping

1921 - American Chemical Society | Journal of the American Chemical Society

Artigo Revisado por pares

Frances J. Hein,

Tópico(s): Atmospheric and Environmental Gas Dynamics

2006 - Springer Science+Business Media | Natural Resources Research

Capítulo de livro Revisado por pares

Xinyu Mao, Bevan Koopman, Guido Zuccon,

Screening documents is a tedious and time-consuming aspect of high-recall retrieval tasks, such as compiling a systematic literature review, where the goal is to identify all relevant documents for a topic. To help streamline this process, many Technology-Assisted Review (TAR) methods leverage active learning techniques to reduce the number of documents requiring review. BERT-based models have shown high effectiveness in text classification, leading to interest in their potential use in TAR workflows. ...

Tópico(s): Machine Learning and Algorithms

2024 - Springer Science+Business Media | Lecture notes in computer science

Artigo Revisado por pares

Melike Bildirici, A. Elçin, Özgür Ömer Ersin,

The study aims to propose a family of Neural Networks (NN) model to achieve improvement in modeling nonlinear cointegration compared to Hansen and Seo (2002) Threshold Autoregressive Vector Error Correction (TAR-VEC) model. Our proposed TAR-VEC-NN family consist of TAR-VEC Multi Layer Perceptron (TAR-VEC-MLP), TAR-VEC Radial Basis Function (TAR-VEC-RBF) and TAR-VEC Recurrent Hybrid Elman (TAR-VEC-RHE) models. TAR-VEC-NN models are also discussed under two modeling strategies, first based on TAR-VEC modeling ...

Tópico(s): Neural Networks and Applications

2009 - Elsevier BV | Expert Systems with Applications

Artigo Acesso aberto Revisado por pares

Nora Aranberri-Monasterio, Sharon O’Brien,

-ing forms in English are reported to be problematic for Machine Transla-tion and are often the focus of rules in Controlled Language rule sets. We investigated how problematic -ing forms are for an RBMT system, translat-ing into four target languages in the IT domain. Constituent-based human evaluation was used and the results showed that, in general, -ing forms do not deserve their bad reputation. A comparison with the results of five automated MT evaluation metrics showed promising correlations. ...

Tópico(s): Speech and dialogue systems

2021 - | Linguistica Antverpiensia New Series – Themes in Translation Studies

Artigo Revisado por pares

Abdelrahman H. Hegazi,

Abstract This study represents a forensic chemical analysis to identify the source(s) of tar balls polluting several beaches of the Mediterranean city of Alexandria, Egypt. Concentrations of six metals (vanadium [V], nickel [Ni], magnesium [Mg], iron [Fe], cobalt [Co], and copper [Cu]) were studied in tar balls, collected from different locations along the coast of the city and in Egyptian crude oils as possible source oils. The metal concentrations were generally higher in tar balls than in the studied ...

Tópico(s): Geochemistry and Geologic Mapping

2009 - Taylor & Francis | Petroleum Science and Technology