Search results for "VDP::Mathematics and natural science: 400::Mathematics: 410"
showing 10 items of 248 documents
Study on Support Vector Machine-Based Fault Detection in Tennessee Eastman Process
2014
Published version of an article in the journal: Abstract and Applied Analysis. Also available from the publisher at: http://dx.doi.org/10.1155/2014/836895 Open Access This paper investigates the proficiency of support vector machine (SVM) using datasets generated by Tennessee Eastman process simulation for fault detection. Due to its excellent performance in generalization, the classification performance of SVM is satisfactory. SVM algorithm combined with kernel function has the nonlinear attribute and can better handle the case where samples and attributes are massive. In addition, with forehand optimizing the parameters using the cross-validation technique, SVM can produce high accuracy i…
A mahalanobis hyperellipsoidal learning machine class incremental learning algorithm
2014
Published version of an article in the journal: Abstract and Applied Analysis. Also available from the publisher at: http://dx.doi.org/10.1155/2014/894246 Open Access A Mahalanobis hyperellipsoidal learning machine class incremental learning algorithm is proposed. To each class sample, the hyperellipsoidal that encloses as many as possible and pushes the outlier samples away is trained in the feature space. In the process of incremental learning, only one subclassifier is trained with the new class samples. The old models of the classifier are not influenced and can be reused. In the process of classification, considering the information of sample's distribution in the feature space, the Ma…
SimReal+ i matematikkundervisning på universitetsnivå En studie av lærerens orkestreringer i relasjon til verktøyets nytteverdi for studentene
2015
Masteroppgave matematikkdidaktikk- Universitetet i Agder, 2015 This thesis is a case study conducted in the first year of engineering studies at the University of Agder. The course observed is physics, where the software SimReal+ is integrated into the teaching. The study focuses the mathematical part of the course related to differentiation and integration. In my study, I focus on both the lecturer and students taking the course. The study examines the teacher-orchestrations that can be identified in lectures and exercises, and perceptions students have related to the usefulness of SimReal+ and some teacher-orchestrations. My research questions are: 1. What types of teacher-orchestrations …
Using the interactive learning environment aplusix for teaching and learning school algebra: A research experiment in a middle school
2011
Published version of an article from the journal: Turkish Online Journal of Educational Technology. Also available from the publisher: http://www.tojet.net/ Open Access Most software tools that have been developed with the aim of helping students to learn school algebra have not yet achieved successful results in classroom. Almost all of them are menu-based systems that provide transformation rules in menus and buttons. Aplusix is a new interactive software tool for learning school algebra. In contrast to existing software tools in mathematics education, Aplusix has been developed to allow students to freely build and transform algebraic expressions as they can do on paper. In addition, Apl…
Elevers matematikksamtaler : Læring i og mellom praksiser
2012
Doktorgradsavhandling ved Universitetet i Agder, Fakultet for teknologi og realfag The aim of this study “Students´mathematical conversations – Learning in and beween practices” is to examine students’ mathematical conversations and the students learning in and between practices. I study what characterizes mathematical conversations, and explore what potential the participation in such conversations in and outside school, have towards critical learning of mathematics. It is an expressed political goal that the subject of mathematics should be more practical in school. The government’s strategic document “Realfag for framtida, [MST for the future] 2010–2014”, describes company as an arena fo…
Quantized State-Feedback Stabilization for Delayed Markovian Jump Linear Systems with Generally Incomplete Transition Rates
2014
Published version of an article in the journal: Abstract and Applied Analysis. Also available from the publisher at: http://dx.doi.org/10.1155/2014/961925 open Access This paper is concerned with the robust quantized state-feedback controller design problem for a class of continuous-time Markovian jump linear uncertain systems with general uncertain transition rates and input quantization. The uncertainties under consideration emerge in both system parameters and mode transition rates. This new uncertain model is more general than the existing ones and can be applicable to more practical situations because each transition rate can be completely unknown or only its estimate value is known. B…
Observer-Based Robust Control for Switched Stochastic Systems with Time-Varying Delay
2013
Published version of an article in the journal: Abstract and Applied Analysis. Also available from the publisher at: http://dx.doi.org/10.1155/2013/320703 Open Access This paper investigates the problem of observer-based robust H ∞ control for a class of switched stochastic systems with time-varying delay. Based on the average dwell time method, an exponential stability criterion for switched stochastic delay systems is proposed. Then, H ∞ performance analysis and observer-based robust H ∞ controller design for the underlying systems are developed. Finally, a numerical example is presented to illustrate the effectiveness of the proposed approach.
Stabilization and controller design of 2D discrete switched systems with state delays under asynchronous switching
2013
Published version of a paper from the journal: Abstract and Applied Analysis. Also available from Hindawi:http://dx.doi.org/10.1155/2013/961870. Open Access This paper is concerned with the problem of robust stabilization for a class of uncertain two-dimensional (2D) discrete switched systems with state delays under asynchronous switching. The asynchronous switching here means that the switching instants of the controller experience delays with respect to those of the system. The parameter uncertainties are assumed to be norm-bounded. A state feedback controller is proposed to guarantee the exponential stability. The dwell time approach is utilized for the stability analysis and controller …
A three-dimensional study of the onset of convection in a horizontal, rectangular porous channel heated from below
2012
Author's version of an article published in the journal: International Journal of Thermal Sciences. Also available from the publisher at: http://dx.doi.org/10.1016/j.ijthermalsci.2011.12.012 The onset of convection is studied in a rectangular channel filled with a fluid saturated porous medium, bounded above and below by impermeable isothermal walls at unequal temperatures and laterally by partially conducting walls. A three-dimensional linear stability analysis is carried out under the assumption of an infinite longitudinal channel length. Then, this assumption is relaxed in order to determine the threshold length for the three-dimensional convection to be the preferred mode at onset. Sens…
Viscous dissipation and thermoconvective instabilities in a horizontal porous channel heated from below
2010
Accepted version of av article from the journal: International Journal of Thermal Sciences. Published version available on Science Direct: http://dx.doi.org/10.1016/j.ijthermalsci.2009.10.010 A linear stability analysis of the basic uniform flow in a horizontal porous channel with a rectangular cross section is carried out. The thermal boundary conditions at the impermeable channel walls are: uniform incoming heat flux at the bottom wall, uniform temperature at the top wall, adiabatic lateral walls. Thermoconvective instabilities are caused by the incoming heat flux at the bottom wall and by the internal viscous heating. Linear stability against transverse or longitudinal roll disturbances …