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Found 6289 publications

Dataflow-based Heterogeneous Code Generator for IoT Applications

Endri Bezati Nebojša Taušan Gábor Paller Gábor Élo Gabor Farkas

Publication Name: International Conference on Model Driven Engineering and Software Development

Publication Date: 2019-01-01

Volume: Unknown

Issue: Unknown

Page Range: 326-332

Description:

The latest wave of connected digital systems, nowadays called Internet of Things (IoT) promises various gains, especially in terms of significant ease of data access. A large number of different platforms for IoT applications,however,makestheirdevelopmentdifficultandtime-consumingleadingtoprojectsthatarefailed to be on time, on budget or fully completed. To address the platform heterogeneity, this paper presents the ongoing work on development environment called Orcc-IoT. Orcc-IoT facilitates the development of IoT by combining dataflow modelling language, heterogeneous code generator and the library of ready-made IoT actors. The utilisation of Orcc-IoT in development is expected to increase the quality, and to reduce the development costs and time-to-market of IoT applications.

Open Access: Yes

DOI: 10.5220/0007496804260432

Numerical methods for solving the modified filter algebraic riccati equation for H-infinity filtering

Zsolt Horváth

Publication Name: Przeglad Elektrotechniczny

Publication Date: 2019-01-01

Volume: 95

Issue: 4

Page Range: 9-15

Description:

This paper presents numerical methods for solving the Modified Filter Algebraic Riccati Equation (MFARE) for synthesis of H-infinity fault detection filters. Two methods are presented, namely the gamma-iteration and then rewriting the MFARE in Linear Matrix Inequalities (LMIs) and casting it as a convex optimization problem. Each algorithm has to ensure the condition for a global convergence and also has to deliver an optimal solution. Not at least the computational cost has to be as small as possible.

Open Access: Yes

DOI: 10.15199/48.2019.04.02

Visibility studies at roundabouts entries

Csaba Koren Zsófia Magyari

Publication Name: Pollack Periodica

Publication Date: 2019-01-01

Volume: 14

Issue: 3

Page Range: 63-74

Description:

Most accidents in roundabouts occur at the entries, partly due to poor visibility. To analyse this problem a sample roundabout with some visibility obstacles was measured by laser scanner and data were put into a 3D model. The fields of view were studied from the viewpoint heights of car and truck drivers as well. To assess the results, three indicators were defined: the hidden sight distance, the hidden sight triangle area and the angle of hide. These indicators were measured in the point cloud model. Through these indicators the adequacy of visibility conditions can be assessed.

Open Access: Yes

DOI: 10.1556/606.2019.14.3.7

Maxwhere 3D capabilities contributing to the enhanced efficiency of the trello 2D management software

Ildiko Horvath

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2019-01-01

Volume: 16

Issue: 6

Page Range: 55-71

Description:

This paper presents an experiment comparing the number of user operations and effectiveness of digital workflow in different cases. The main goal of this study is to systematically compare the effectiveness of Trello collaborative project management software in Windows 2D operating system and on the MaxWhere 3D VR platform. All comparisons are made based on a novel framework that focuses on both quantitative and qualitative assessments of user interactions required for the completion of digital projects within different computational environments. The results of the experiment, evaluated in terms of the proposed framework, point to the conclusion that when using Trello in conjunction with MaxWhere’s 3D VR spaces, users are able to accomplish the same digital workflows with 72% less elementary user operations, and with 80% less time spent on overview-related tasks. In the 3D experiment, the value of the Monitoring Density metric introduced in this paper increased almost 300-fold, from 125 to 3125. Based on these results, the paper concludes that the MaxWhere 3D VR platform offers project managers a number of ways to accomplish tasks that would otherwise require extremely complicated digital workflows in more traditional 2D environments.

Open Access: Yes

DOI: 10.12700/APH.16.6.2019.6.5

Vibration damping measurement on car windshields

Balázs Vehovszky Karl Slenczka Tamás Jakubík István Horváth Martin Schuster

Publication Name: Periodica Polytechnica Mechanical Engineering

Publication Date: 2019-01-01

Volume: 63

Issue: 1

Page Range: 1-6

Description:

Knowledge of the damping properties of a windshield is a fundamental element of the acoustical characterization of a car. The measuring method of damping for a windshield is presented in the paper. The damping loss factor – as a basic measure of mechanical damping – was determined experimentally by two means: the reverberation time from impact hammer testing as well as the modal behavior from 3D laser scanning vibrometer measurements. The results proved that the modal shapes have a fundamental effect on the measured damping values.

Open Access: Yes

DOI: 10.3311/PPme.11559

Microbiological testing of drinking water in the western transdanubian region of Hungary using API tests

Roland Miseta A. Zseni Bálint Németh

Publication Name: Wit Transactions on Ecology and the Environment

Publication Date: 2019-01-01

Volume: 239

Issue: Unknown

Page Range: 193-203

Description:

Using standard and routine methods for drinking water microbiological quality control may lead to uncertainty. In some cases, biochemical tests for confirmation of presumptive colonies have negative results. It can also happen that the target bacteria cannot be found, but the high concentration of the background biota contaminates water sampling points or even the entire water supply system. The aim of the study was to investigate and identify bacterial colonies retrieved from water samples of drinking water supply systems using a relatively cheap, fast and easy-to-use method as well as to acquire information on the presence of pathogens in the background biota. To achieve our goals, water samples from 18 western Hungarian settlements were collected during a two month period. A total of 66 morphologically different bacterial colonies growing on four media were tested for taxonomic identification by three different API (Analytical Profile Index) tests which are suitable for the identification of bacteria at species level. Out of the 66 bacterial colonies involved in the study, 58 could be identified by API tests. During the identification, the presence of 27 different taxa were proved in the water samples. As a result of our research, species (Aeromonas hydrophila, Pseudomonas fluorescens, Burkholderia cepacia) that can cause confusion in the evaluation of water samples by forming morphologically typical colonies on the medium or presenting in high number of colony form units as background contaminants were identified. The presence of species (Pseudomonas aeruginosa, Aerococcus viridans, Aeromonas hydrophila, Gemella morbillorum, Streptococcus constellatus) which originated from the background biota on different agar plates and can cause human diseases, were also confirmed. Even if the organisms which indicate water quality degradation are not present in the water sample, the background biota may contain human pathogenic bacteria that might lead to health problems when enriched in the drinking water supply system.

Open Access: Yes

DOI: 10.2495/WS190171

Development of a low-fat lactose-free dairy spread containing viable lactic acid bacteria – Part 2: Texture analysis and sensory evaluation

Gábor Kátay László Varga

Publication Name: Elelmiszervizsgalati Kozlemenyek

Publication Date: 2019-01-01

Volume: 65

Issue: 3

Page Range: 2573-2588

Description:

The objective of our work was to compare the main texture characteristics of the low-fat (30%), lactose-free dairy spread developed by us, containing viable lactic acid bacteria, and those of commercially available dairy spreads by an objective, reproducible, instrumental test, and then to assess the expected market reaction to our new product. The results of the rheological tests have shown that, in terms of its texture, our lactose-free dairy spread is similar to currently commercially available similar dairy products of adequate quality. Compared to 25 to 39% fat products, it is neither softer, nor stickier, its spreadability is close to that of usual dairy spreads. The judges (250 people) found the flavor and texture of the developed product significantly better (P<0.05) than those of one of the traditional dairy spreads that has been available in stores for a long time. However, in terms of spreadability, the latter dairy product was found to be superior (P<0.05). It was found that our new product could be received well when placed on the market, however, it should be emphasized during its introduction that, in addition to the ideal texture characteristics and nutritional physiology properties of the well-known and popular dairy spreads, it also has added functional benefits since it is lactose-free and contains viable lactic acid bacteria.

Open Access: Yes

DOI: DOI not available

Evaluation of acoustic frequency methods for the prediction of propeller noise

Dániel Feszty Mark T. Kotwicz Herniczek Jong Park Sid Ali Meslioui Fred Nitzsche

Publication Name: AIAA Journal

Publication Date: 2019-01-01

Volume: 57

Issue: 6

Page Range: 2465-2478

Description:

The accuracy of several computationally inexpensive acoustic frequency methods is evaluated across a range of propeller geometries and operational conditions. The acoustic models considered predict both near-field and far-field harmonic noise. The implemented models approximate or ignore chordwise noncompactness such that they do not require chordwise aerodynamic data, and therefore do not need to be coupled to a panel or grid-based aerodynamic solver. Each implemented method is compared to 14 test cases originating from nine separate published acoustic experiments. The experimental data considered encapsulate a range of propeller geometries, blade numbers, microphone locations, tip speeds, and forward Mach speeds. The implemented acoustic models demonstrate reasonable agreement with the experimental data, particularly for the prediction of the maximum tonal noise for which Hanson’s model showed the greatest overall accuracy with an average error of 5.9 dB. Using different prediction models based on the freestream velocity reduces the error to 4.7 dB. The presented results suggest that the implemented acoustic methods remain a valuable resource for propeller noise prediction, especially for design and optimization studies, in which a low runtime is important.

Open Access: Yes

DOI: 10.2514/1.J056658

Warping transfer superelement model for bolted end-plate connections subject to 3D loads

B. Vaszilievits-Sömjén Majid Movahedi Rad J. Szalai

Publication Name: Sdss 2019 International Colloquium on Stability and Ductility of Steel Structures

Publication Date: 2019-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

A simple beam element based modelling technique has been developed which makes possible to analyze frames made of I sections with column-rafter bolted end-plate connections, subject to 3D loads, compatible with the thin walled beam theory with 7DOF beam elements. The model previously developed by the same team for welded connections has been extended with the addition of linear spring elements to model the bolts located at the upper and lower beam flange level. The spring stiffnesses are calculated based on the extension of the Eurocode component method and verified by simulations performed with FEA software Abaqus.

Open Access: Yes

DOI: DOI not available