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Found 6515 publications

An assessment of ambient air quality in Gyor, Hungary

Zso´fia Csanádi Andrea Szabo´ Nagy

Publication Name: World Congress on Civil Structural and Environmental Engineering

Publication Date: 2018-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

This paper presents an assessment of air quality of the city Gyor, located 120 km west to the capital of Hungary. Two urban air monitoring stations are operated by the local Environmental Protection Laboratory in the city. The concentration data of major air pollutants (CO, NOx, SO2, C6H6, O3, PM10, PM2.5), PM10-bound heavy metals (Pb, Cd, As and Ni) and some polycyclic aromatic hydrocarbons (PAHs) including benzo(a)pyrene (BaP), benzo(a)anthracene, sum of three benzofluoranthene (b, k and j) isomers, indeno(1,2,3-cd)pyrene and dibenzo(a,h)anthracene are available for the assessment based on the latest published monitoring data of the Hungarian Air Quality Monitoring Network. The levels of pollutants were compared with the Hungarian and EU limit or target values defined for health protection and the WHO air quality guidelines (AQGs) or estimated reference levels (RLs). Moreover, the air quality index values for the pollutants were calculated. The results indicated that the main pollutants were BaP, PM10 and PM2.5 in the Gyor atmosphere. The annual mean concentration of PM10 and PM2.5 aerosols reached the WHO AQGs (20 and 10 μg/m3), while that of the BaP it was about 5.5 times higher than the WHO RL value of 0.12 ng/m3. However, a good or excellent air quality was identified for all examined air pollutants based on the concentration data evaluated by the Hungarian and EU limit or target values.

Open Access: Yes

DOI: 10.11159/awspt18.112

Improvement the energy storage with ultracapacitor in metro railcar by modeling and simulation

István Szénásy

Publication Name: 2008 IEEE Vehicle Power and Propulsion Conference Vppc 2008

Publication Date: 2008-12-29

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

This paper focuses on the use of modeling and simulation for the renewable energy. An energy storage system for improving performance of electric vehicles is presented. The supercapacitor contributes to the rapid energy recovery associated with regenerative braking in electric vehicles. This power system allows the acceleration and deceleration of the vehicle with minimal loss of energy. Short-distance passenger traffic on electrified lines is a domain where brake energy recuperation might reduce the total energy consumption significantly. In this paper the results of simulation model by Matlab-Simulink for an urbanmetro railcar and the method for reduce the need value of capacitance are presented. © 2008 IEEE.

Open Access: Yes

DOI: 10.1109/VPPC.2008.4677664

Nodal and edge finite element analysis of eddy current field problems

Miklós Kuczmann

Publication Name: Przeglad Elektrotechniczny

Publication Date: 2008-12-01

Volume: 84

Issue: 12

Page Range: 194-197

Description:

Eddy current field problems can be solved by different potential formulations based on the "quasi-static" Maxwell's equations. The potential formulations are obtained using a vector potential and a scalar potential, the most widely used techniques are the A, V-A, the T,φ-φformulations and their combinations. Vector potentials can be approximated by nodal or edge finite elements, scalar potentials are approximated by scalar elements. The paper presents and compares these formulations through TEAM Problem No. 7 containing a multiply connected region.

Open Access: Yes

DOI: DOI not available

Overview of auditory representations in human-machine interfaces

Ádam Csapó György Wersényi

Publication Name: ACM Computing Surveys

Publication Date: 2013-11-01

Volume: 46

Issue: 2

Page Range: Unknown

Description:

In recent years, a large number of research projects have focused on the use of auditory representations in a broadened scope of application scenarios. Results in such projects have shown that auditory elements can effectively complement other modalities not only in the traditional desktop computer environment but also in virtual and augmented reality, mobile platforms, and other kinds of novel computing environments. The successful use of auditory representations in this growing number of application scenarios has in turn prompted researchers to rediscover the more basic auditory representations and extend them in various directions. The goal of this article is to survey both classical auditory representations (e.g., auditory icons and earcons) and those auditory representations that have been created as extensions to earlier approaches, including speech-based sounds (e.g., spearcons and spindex representations), emotionally grounded sounds (e.g., auditory emoticons and spemoticons), and various other sound types used to provide sonifications in practical scenarios. The article concludes by outlining the latest trends in auditory interface design and providing examples of these trends.

Open Access: Yes

DOI: 10.1145/2543581.2543586

Taylor series method with numerical derivatives for initial value problems

Gyozo Molnárka E. M. Miletics

Publication Name: Journal of Computational Methods in Sciences and Engineering

Publication Date: 2004-01-01

Volume: 4

Issue: 1-2

Page Range: 105-114

Description:

The Taylor series method is one of the earliest analytic-numeric algorithms for approximate solution of initial value problems for ordinary differential equations. The main idea of the rehabilitation of these algorithms is based on the approximate calculation of higher derivatives using well-known technique for the partial differential equations. In some cases such algorithms will be much more complicated than a R-K methods, because it will require more function evaluation than well-known classical algorithms. However these evaluations can be accomplished fully parallel and the coefficients of truncated Taylor series can be calculated with matrix-vector operations. For large systems these operations suit for the parallel computers. The approximate solution is given as a piecewise polynomial function defined on the subintervals of the whole interval and the local error of this solution at the interior points of the subinterval is less than that one at the end point. This property offers different facility for adaptive error control. This paper describes several above-mentioned algorithms and examines its consistency and stability properties. It demonstrates some numerical test results for stiff systems herewith we attempt to prove the efficiency of these new-old algorithms.

Open Access: Yes

DOI: 10.3233/jcm-2004-41-213

Determination of the health-protective effect of ancient cereals and one possibility of increasing their functionality

E. Lakatos Székelyhidi Rita Beatrix Sik Anna Márkus

Publication Name: Cereal Research Communications

Publication Date: 2024-03-01

Volume: 52

Issue: 1

Page Range: 247-253

Description:

This study aimed to examine the differences between the antioxidant capacity, and the total polyphenol content of the ancient grains namely Einkorn (Triticum monococcum L.) and Khorasan (Triticum turanicum) compared with wheat (Triticum aestivum L.), furthermore attempt to create a functional loaf enriched with rosemary (Salvia Rosmarinus Spenn.). To achieve this goal, 1, 3, and 5% of rosemary were added to the loafs made of Einkorn, Khorasan, and common wheat flour, and then the changes in their antioxidant and polyphenol content were examined. Based on the spectrophotometric results, it can be said that the type of wheat clearly affects the amount of the tested components. In all cases, the loafs made from common wheat contained the least amount of antioxidants (0.74 mg AAE/g) and polyphenols (0.41 mg GAE/g). On the other hand, Khorasan loaves showed outstanding values in terms of their antioxidant (0.89 mg AAE/g) and polyphenol (0.68 mg GAE/g) content. Einkorn loaves contained smaller amounts of the tested antioxidants (0.71 mg AAE/g) and polyphenols (0.51 mg GAE/g), but they were still better than common wheat loaves. The addition of rosemary can significantly increase the amount of compounds with an antioxidant effect in bakery products, but care must be taken to preserve the favorable organoleptic properties. It has been proven that ancient grains have a more positive physiological effect than common wheat, and the health-protective properties of bakery products can be increased by adding herbs. Graphical abstract: (Figure presented.)

Open Access: Yes

DOI: 10.1007/s42976-023-00384-4

Comparative analysis of the process for compliance with the European Charter of Local Self-Government in The Czech Republic, Hungary and Slovakia - with special emphasis on economic conditions and Hungarian atypical features

Laszlo Vasa Csaba Lentner Szilárd Hegedűs László Nagy

Publication Name: Economic Annals Xxi

Publication Date: 2018-12-24

Volume: 173

Issue: 9-10

Page Range: 10-18

Description:

The aim of this paper is to analyse legal and financial dynamics of the self-governance in three countries of the Visegrad Group: The Czech Republic, Hungary and Slovakia. The paper explores compliance with the European Charter of Local Self-Government, financial independence and operational features of self-governance. The paper provides an overview of the regulatory environment that was set up for the local government in the Visegrad countries, examines the powers by local government, and the degree of its financial independence. The financial aspects of self-government are compared, and compliance with major fiscal rules is examined.

Open Access: Yes

DOI: 10.21003/ea.V173-02

Mathematical modeling of automotive supply chain networks

Krisztián Szabó Akos Domotorfi Tamás Péter

Publication Name: Periodica Polytechnica Transportation Engineering

Publication Date: 2016-01-01

Volume: 44

Issue: 3

Page Range: 181-186

Description:

The aim of this research is to set up a possible model for describing automotive supply chain networks. The work to be presented analyses the real-world environment and its changes in a broader view. The research provides the extension of the mathematical modeling domain, accordingly. The paper studies the basic relational structure of automotive supply chain, where the methodology is determined by the classical business strategic levels. This is done by combining the theories of network and theories for traffic systems. We uncover the hidden relational parallelism between the automotive supply chain and positive systems, complex networks and find that the industry network shows some similar scale-free structural properties indicating the existence of a typical dependence and dominance structure with complex dynamical behavior.

Open Access: Yes

DOI: 10.3311/PPtr.9544

One-at-a-Time sensitivity study of a tree burning simulation

László Környei Flóra Hajdu Rajmund Kuti

Publication Name: Pollack Periodica

Publication Date: 2024-03-22

Volume: 19

Issue: 1

Page Range: 53-59

Description:

The aim of the research was to carry out the One-at-a-Time sensitivity analysis of a tree burning experiment simulation with a novel fuzzy logic-based method. It was observed that the precent of the remaining tree is sensitive to the moisture content, the crown-base diameter and the tree height. The other variables, which are maximum mass loss rate, maximum heat release rate, and maximum temperature at the top of the tree are moderately sensitive or not sensitive to the selected parameters. The presented results can be used in sensitivity studies and wildfire simulations.

Open Access: Yes

DOI: 10.1556/606.2023.00850