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Found 6289 publications

Improvement and application of the viscous-type frequency-dependent preisach model

Miklós Kuczmann Gergely Kovács

Publication Name: IEEE Transactions on Magnetics

Publication Date: 2014-01-01

Volume: 50

Issue: 2

Page Range: 385-388

Description:

Iron parts of electrical machines are made of nonoriented isotropic ferromagnetic materials. The finite element method (FEM) is usually applied in the numerical field analysis and design of this equipment. The scalar Preisach hysteresis model has been implemented for the simulation of static and dynamic magnetic effects inside the ferromagnetic parts of motors. The dynamic model is an extension of the static one; an extra magnetic field intensity term is added to the output of the static inverse model. This is a viscosity-type dynamic model. The fixed point method with stable scheme has been realized to take frequency-dependent anomalous losses into account in FEM. This scheme can be used efficiently in the frame of any potential formulations of Maxwell's equations. The comparison between measured and simulated data using a toroidal core shows a good agreement. A modified nonlinear version of T.E.A.M. Problem No. 30.a is also shown to test the hysteresis model in the FEM procedure. © 1965-2012 IEEE.

Open Access: Yes

DOI: 10.1109/TMAG.2013.2283398

Computational intelligence for gestural communication using emotional model

No authors available

Publication Name: IWACIII 2013 - 3rd International Workshop on Advanced Computational Intelligence and Intelligent Informatics

Publication Date: 2014-01-01

Volume:

Issue:

Page Range: Unknown

Description:

When conducting natural communication in addition to perform verbal communication, non-verbal communication such as gestural information should also be understood. By the word "understand" we mean not only the recognition of one action, but also grasp the meaning of the gesture itself. Therefore, in order to understand the meaning of an action, in this paper we propose emotional model along with the gesture recognition technique. First we discuss the gesture recognition method using iPhone camera by applying steady state genetic algorithm, spiking neural network and self organizing map. After that we use the gesture recognition result as an input data for the emotional model.

Open Access: No

DOI: DOI not available

Defining Correlation between the Modal Split of Inhabitants and Students and the Location of Housing Areas and Schools with the Analysis of Travel Plans

Petra Szakonyi Emese Mako

Publication Name: Transportation Research Procedia

Publication Date: 2014-01-01

Volume: 4

Issue: Unknown

Page Range: 271-285

Description:

Across the world there is an increasing interest in managing car traffic. One approach developed for addressing the journey to work is known as 'workplace travel planning'. In the recent years the authors participated in two Intelligent Energy Europe projects (Pro.motion and Travel Plan Plus project) which aim was to deliver transport-sector energy savings by creating travel plans. During the development of the projects two local travel plans were worked out, one for the residential area of Ménfocsanak, in the city Gyor, Hungary and one for the elementary educational institutions of Gyor. The main objective of all these studies were to reduce the problems caused by private car users and more over to promote sustainable mobility choices for target groups. The main objective of these studies were to reduce the problems, caused by private car users and more over to promote sustainable mobility choices for target groups. The results of the projects showed us, that travel plans are effective tools in order to solve mobility challenges in a sustainable way and that land-use methods have strong effects on the success of travel plans.

Open Access: Yes

DOI: 10.1016/j.trpro.2014.11.021

A regularized method of fundamental solutions for 3D and axisymmetric potential problems

No authors available

Publication Name: CMES - Computer Modeling in Engineering and Sciences

Publication Date: 2014-01-01

Volume: 101

Issue: 6

Page Range: 365-386

Description:

The Method of Fundamental Solutions (MFS) is investigated for 3D potential problem in the case when the source points are located along the boundary of the domain of the original problem and coincide with the collocation points. This generates singularities at the boundary collocation points, which are eliminated in different ways. The (weak) singularities due to the singularity of the fundamental solution at the origin are eliminated by using approximate but continuous fundamental solution instead of the original one (regularization). The (stronger) singularities due to the singularity of the normal derivatives of the fundamental solution are eliminated by solving special auxiliary subproblems (desingularization). The desingularization idea is similar to a previously published technique and is completely independent of the applied regularization technique. The presented method produces well-conditioned or moderately ill-conditioned matrices in the resulting linear system of algebraic equations, while the accuracy remains acceptable. No boundary mesh structure is needed. The method is generalized to 3D axisymmetric potential problems in a natural way, despite in this case the fundamental solution does not remain a radial function. The use of extremely ill-conditioned matrices is still avoided.

Open Access: No

DOI: DOI not available

Defining energy- and cost-saving potentials and their application in optimal building refurbishment

Árpád Csík Tamás Csoknyai

Publication Name: Environmental Engineering and Management Journal

Publication Date: 2014-01-01

Volume: 13

Issue: 11

Page Range: 2771-2779

Description:

In this paper, we develop a rigorous theoretical framework and a practical implementation for the evaluation of the energy- and cost-saving potential of buildings. The goal is to promote sustainability in the context of building energetics by achieving the most efficient, optimal exploitation of the financial resources available for refurbishments. The practical realization of this concept requires the evaluation of the optimal refurbishment cost that maximizes the net energetic or financial savings during the life cycle of the building. On the one hand, too small a refurbishment cost might lock-in a substantial amount of energy and cost savings potential. On the other hand, refurbishment costs that are too high due to unnecessarily implemented energy-saving measures are likely to waste financial resources. The key concept behind the theory is the novel definition of the reference value used for the computation of the energy- and cost-saving potentials. From a mathematical point of view, the reference value is obtained by two subsequent optimizations. First, a constrained, single-objective optimization is used to evaluate the best energetic state of the building as a function of the refurbishment cost. Second, a simple unconstrained search must be performed to obtain the minimum value and the minimum place of the one-dimensional cost function. The proposed framework automatically provides personalized solutions corresponding to the actual technical characteristics of the building. These solutions are optimal under the given circumstances of the actual refurbishment, resulting in either the highest possible energy- or cost-saving amounts during the life cycle of the building.

Open Access: Yes

DOI: 10.30638/eemj.2014.309

Investigation of confinement effect by using the multi-level shear box test

J. Klompmaker Ferenc Horvát

Publication Name: 10th International Conference on Geosynthetics Icg 2014

Publication Date: 2014-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

The stabilisation and reinforcement of crushed stone aggregate in infrastructural applications using geogrid reinforcement is based on the phenomenon called the "interlocking effect". Through shear interaction of the aggregate with the geogrid, the aggregate is laterally restrained and tensile forces are transmitted from the aggregate to the geogrid. This interaction helps reducing lateral movement of the aggregate and optimises road/track performance. It is well known that this strengthening effect depends on several influencing factors. It is still difficult to quantify the true reinforcement efficiency with regard to the limit of the lateral restraint effect (or confining resistance) over the depth of the aggregate layer being placed on top of the geogrid. To be able to quantify the confining resistance efficiency of geogrids over the depth of the installed aggregate layer a laboratory test was developed (Multi-level shear box test) which allows measuring the shear resistance as a function of the distance from the geogrid layer (in vertical direction). This paper will describe the methodology of the so called "Multi-level shear box test" as well as the results of the confinement efficiency of different type geogrids in combination with railway ballast.

Open Access: Yes

DOI: DOI not available

Visegrád: The Evolving Pattern of Coordination and Partnership After EU Enlargement

Eamonn Butler Károly Grúber Csaba Töro

Publication Name: Europe Asia Studies

Publication Date: 2014-01-01

Volume: 66

Issue: 3

Page Range: 364-393

Description:

Multilateral, subregional partnerships are one of the defining features of contemporary European politics. The 2004 enlargement of the European Union introduced a new partnership entity to the mix-the Visegrád Group of states, comprising the Czech Republic, Hungary, Poland and Slovakia-which offers its members a useful model to discuss and represent common interests in a collective manner within the regional and international political landscape. The article provides a reflection on the evolution of the Visegrád Group of states since 2004. It examines four key policy areas (institutional candidacy, energy policy, eastern neighbourhood and defence policy) where the group has either learned some difficult lessons or is seeking to apply those lessons. The article suggests that the Visegrád Group's greatest strength lies in its flexibility to become more responsive to the challenges it faces and it is likely therefore to remain appealing to its member states and to be a permanent feature within the wider cohort of European Union subregional partnerships. © 2013 University of Glasgow.

Open Access: Yes

DOI: 10.1080/09668136.2013.855392

Time optimal control of four-in-wheel-motors driven electric cars

Gyorgy Max Bela Lantos

Publication Name: Periodica Polytechnica Electrical Engineering and Computer Science

Publication Date: 2014-01-01

Volume: 58

Issue: 4

Page Range: 149-159

Description:

The paper deals with the time optimal control of automatically driven electric cars in a test path under state and input constraints. The problem can be formulated as a dynamic nonlinear optimal control problem (DNOCP). The resulting DNOCP is solved by reformulating it to a static nonlinear program (NLP) using time discretization and direct multiple shooting methods. A novel method is presented to convert the optimal solution obtained using the single-track model to the optimal control of four-in-wheels-motors driven (4WD) cars. The conversion assures similar motion of the COG of both models and optimal distribution of the longitudinal wheel forces. A discrete model predictive control (MPC) is proposed for the linearized 4WD vehicle model under perturbations which uses the distributed wheel forces and optimizes the perturbations with analytically solvable end constraints. The elaborated method can form the basis to generate an offline database of a general collision avoidance system (CAS).

Open Access: Yes

DOI: 10.3311/PPee.7806

Fuzzy signature structure-based finite-state machines in a residential building renovation procedure

Gergely Molnarka L. T. Kóczy

Publication Name: Civil Comp Proceedings

Publication Date: 2014-01-01

Volume: 105

Issue: Unknown

Page Range: Unknown

Description:

Twenty years after the transition to the market-based housing sector the overall physical condition of pre-war urban-type residential houses remained below standard in Hungary. Among other factors, the fragmented ownership structure (at present, the capital-scarce former tenants constitute the stakeholders' community), and the given physical condition of the residential houses has resulted in difficulties in maintenance and repair. The options in the renovation process are limited by financial capabilities, however, the essential problem with maintenance originates from the unprofessional approach in decision-making. Although several decision-support tools exist that may help the stakeholders' communities, some properties of these tools make them unsuitable, or, as in the case of the facility management systems, their application may result in oversized expenses with needless functions. As a combination of the fuzzy signature structure and the principles of finite-state machines a new formal method is proposed for generate a tool for the supporting stakeholders' decisions in the building rehabilitation process, concerning necessity, cost efficiency and quality. With the support of information obtained from building diagnostic surveys, technical guides and contractors' billing databases an optimized renovation protocol is proposed.

Open Access: Yes

DOI: DOI not available