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Publications - 6289

Model-based control algorithm development of induction machines by using a well-defined model architecture and rapid control prototyping

Krisztian Horvath Marton Kuslits Szilárd Lovas

Publication Name: Electrical Engineering

Publication Date: 2020-09-01

Volume: 102

Issue: 3

Page Range: 1103-1116

Description:

This paper presents a new control algorithm development approach for induction machines by using model-based design and a systematically built model architecture implemented in MATLAB/Simulink. The model architecture follows a three-layer structure, and it is developed according to the principle of functional decomposition and the needs of reusability and expandability. The first model layer consists of elementary model and algorithm components, the second contains a machine simulation model and a field-oriented control (FOC) algorithm, built upon the first layer’s components, and the third realises the executable models by connecting the models and algorithms defined in the second layer. Furthermore, rapid control prototyping (RCP) is discussed as an experimental validation method, and an experimental setup with RCP is also introduced. The application of the presented methods is demonstrated by simulations as well as by experiments, and by using a control algorithm based on FOC as an example.

Open Access: Yes

DOI: 10.1007/s00202-020-00935-6

The effect of dietary glycerol supplementation on milk production and composition, blood parameters and performance of lactating sows

Tamás Tóth George Bázár Orsolya Vida János Fábián Egri Borisi

Publication Name: Livestock Science

Publication Date: 2019-12-01

Volume: 230

Issue: Unknown

Page Range: Unknown

Description:

Modern lactating sows have an increased demand for nutrients for the large litter size compared to the traditional genotypes. Glycerol is considered to be a good alternative to moderate the energy deficiency and provide energy supply in the feed of lactating sow. The aim of our study was to evaluate the effect of a liquid “feed grade” glycerol source on the milk production and milk composition of sows including its fatty acid profile, on the major physiological indicators of sows, and on the digestibility of nutrients. The trial was conducted with Danish Landrace×Danish Yorkshire (323±17.0 kg) sows (n = 12/treatment) and their litters. 5% glycerol supplementation increased the milk yield on d 21 of lactation [control (C): 8.94±2.27 kg/d vs. 5% glycerol (G): 10.39±1.56 kg/d; P<0.05], but had no effect on the milk production of the total lactation period (P>0.05). Glycerol inclusion decreased the milk protein content on d 14 and d 21 and had a decreasing effect on the milk protein (CP) content in the total lactation period, either (C: 5.33±0.40 g/100 g milk vs. G: 5.15.±0.33 g/100 g milk; P<0.05). Glycerol supplementation did not influence the dry matter (DM), ether extract (EE) and lactose content. 5% glycerol did not have any effect on the feed intake, live weight, back-fat thickness, and weaning-to-oestrus interval of lactating sows and neither did significantly influence the weaning weight of the piglets. There was no difference between control and experimental groups in total protein, albumin and triglyceride concentration of blood samples of sows and in the activity of liver enzymes (ALT, AST, GGT), but there was a tendency (P<0.10) for increased plasma glucose (C: 4.94±0.29 mmol/L vs. G: 5.17±0.55 mmol/L) and cholesterol (C: 2.10±0.27 mmol/L vs. G: 2.34±0.33 mmol/L) in the experimental group. Due to the 5% glycerol supplementation, the ratio of total saturated fatty acids (SFAs) of the milk fat decreased (C: 43.47±3.37 g/100 g fatty acid vs. G: 39.39±4.51 g/100 g fatty acid; P<0.05). In the SFAs group the ratio of C14:0 and C16:0 fatty acids decreased significantly compared with the control group (P<0.05). In contrast, there was a tendency for increased total monounsaturated fatty acids (MUFAs) content of the milk (C: 43.62±2.54 g/100 g fatty acid vs. G: 47.11±4.29 g/100 g fatty acid; P<0.10) but the total polyunsaturated fatty acids (PUFAs) content was not affected (C: 12.88±1.23 g/100 g fatty acid vs. G: 13.50±0.64 g/100 g fatty acid;). The total n-3 PUFAs proportion in the milk increased (C: 0.63±0.06 vs. G: 0.68±0.05; P<0.05). No differences were observed in the apparent total tract digestibility of DM, CP, EE and crude fiber between control and experimental groups. Our findings have shown that 5% “feed grade” glycerol can be fed with lactating sows without having a negative effect on the performance. Additional dose trials are needed to be performed in order to further study the effect of glycerol supplementation on milk production and on metabolic processes of lactating sows.

Open Access: Yes

DOI: 10.1016/j.livsci.2019.103859

Floristic and vegetation change on the Sphagnum-dominated mire of Egerbakta

János György NAGY Dániel TÖPLER János András DUDÁS Júlia HOBLYÁK

Publication Name: Kitaibelia

Publication Date: 2025-01-01

Volume: 30

Issue: 1

Page Range: 129-138

Description:

Since 1988, open stands of Menyanthes trifoliata have disappeared, communities of Carex rostrata have declined, and the Sphagnum-dominated willow carr has expanded. The mire’s central associations include Caricetum rostratae, Salici cinereae–Sphagnetum recurvi sphagnetosum squarrosi, and Calamagrosti–Salicetum cinereae. In the mainly nudum lagg zone, the following communities occur: Bidenti–Polygonetum hydropiperis, Bidenti–Polygonetum hydropiperis urticetosum dioicae, Caricetum acutiformis, Juncetum effusi, Glycerietum maximae, and a community dominated by Poa nemoralis. We recorded 77 vascular plant species, 62 of which were new to the site. Rare species have declined in number: Menyanthes trifoliata and Cicuta virosa are now absent, and of the former eight Sphagnum species, only Sphagnum squarrosum remains. The original Salici cinereae–Sphagnetum recurvi sphagnetosum recurvi subassociation transitioned into Salici cinereae–Sphagnetum recurvi sphagnetosum squarrosi after the mire remained completely dry and peat-moss-free for several years around 2000. Central communities reflect a cool, moderately acidic, oligotrophic environment with low pH and conductivity. In contrast, lagg vegetation indicates warmer, nutrient-rich, less acidic conditions. The mire’s most valuable zone is its central, Sphagnum-rich area, whose preservation depends on a natural water supply maintained by continuous forest cover in the catchment and stable or reduced large game populations.

Open Access: Yes

DOI: 10.17542/kit.30.068

Crisis, institutional change and peripheral industrialization: Municipal-central state relations and changing dependencies in three old industrial towns of Hungary

Ernő Molnár Gergő Gajzágó Melinda Mihály Erika Nagy

Publication Name: Applied Geography

Publication Date: 2021-11-01

Volume: 136

Issue: Unknown

Page Range: Unknown

Description:

This paper aims to discuss radical changes, institutional responses and their socio-spatial consequences by focusing on reorganisation of institutional settings of local economic development after the global financial crisis (2008). We focus on the complexity of institutional change and social relations driving those in three old industrial towns (Dunaújváros, Martfű and Tatabánya in Hungary) that faced a functional, cognitive and political lock-in in the 1990s, and emerged as spaces of encounter of global production networks, governmental development policies and local society in the 2000s. This entailed a complex and dynamic assembly of various interests and strategies, providing a scope for local institutional experimentations that were interrupted by the global crisis and the resulting macro-structural changes. We place municipal agency, its uneasy, contested and changing relation to the central state in the focus. We discuss how the introduction of a new regulative system and institutional-spatial hierarchies in Hungary after the 2008 crisis enhanced central state power, and how that was mobilized to develop a new regime in which communities were losing control over their resources, and local assets were being channelled in peripheral industrialization orchestrated by the central government. Discussing municipal agency in a strategic-relational approach allows us to highlight the depth and multiple consequences of the crisis locally beyond market relations, giving an insight in the spatial rearrangement of power in relation to peripheral industrialization.

Open Access: Yes

DOI: 10.1016/j.apgeog.2021.102576

DOES TELEWORK WORK? GAUGING CHALLENGES OF TELECOMMUTING TO ADAPT TO A “NEW NORMAL”

Agota Giedrė Raišienė Tibor Dory Violeta Rapuano Kristina Varkulevičiūtė

Publication Name: Human Technology

Publication Date: 2021-10-31

Volume: 17

Issue: 2

Page Range: 126-144

Description:

The paper aims to contribute to a deeper understanding of organisation management while telecommuting. With exploratory factor analysis (EFA), we define the specific set of telework organising efficiency characteristics. We determined the number of factors with Kaiser Eigenvalues rule as well as Cattel’s scree criterion. We conducted the study in Lithuania, the country with a low percentage of teleworkers until organisations have been urged to properly implement their performance to remote means after the COVID-19 quarantine was announced. This paper reveals that the fundamental challenges of teleworking are the feedback issues related to working accomplishment, especially to the task and process overload, and individual self-organisation ability. Moreover, the flexibility of work organisation represents a unique characteristic of telework, and managers should cooperate more effectively with teleworkers to keep them motivated.

Open Access: Yes

DOI: 10.14254/1795-6889.2021.17-2.3

Case study on the tactical level of an autonomous vehicle control

Claudiu Radu Pozna Csaba Antonya Ernö Horváth

Publication Name: International Conference on Electrical Computer Communications and Mechatronics Engineering Iceccme 2021

Publication Date: 2021-10-07

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

In this paper, a case study is presented on the tactical level of autonomous vehicle control. Inspired by the human driver behavior, vehicle control is structured in a hierarchy on three levels: the strategic, the tactical, and the operational level. These are connected by specific links, and based on prior information and models, are transforming the input data from the environment into actuator commands on the various degree of freedom of the vehicle. The case study is presenting a simulation of a scenario, detailing the vehicle models with sensors, the collection of behavior, and the behavior selector.

Open Access: Yes

DOI: 10.1109/ICECCME52200.2021.9590868

Vehicle dynamic-based approach for the optimization of traffic parameters of the intelligent driver model (IDM) and for the support of autonomous vehicles’ driving ability

István Lakatos Tamás Péter

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2019-01-01

Volume: 16

Issue: 3

Page Range: 121-140

Description:

The research identifies the dynamical parameters in the area of mechanics within the base of traffic model parameters used by the Intelligent Driver Model (IDM), which are the highest acceleration parameters set by the vehicle, the desired speed parameters of the vehicle and the distance-keeping parameters of the vehicle. All this facilitates the automatic control of autonomous electric vehicles in certain vehicle groups.

Open Access: Yes

DOI: 10.12700/APH.16.3.2019.3.7

Two operating states-based low energy consumption vehicle control

István Lakatos Ernö Horváth Péter Korös Ferenc Szauter

Publication Name: Proceedings of the ASME Design Engineering Technical Conference

Publication Date: 2017-01-01

Volume: 9

Issue: Unknown

Page Range: Unknown

Description:

The current paper presents a realization of a complex vehicle control task. The goal was to consume the lowest possible energy in a less than 100 kg, wheel hub motor-driven vehicle. The realization is based on two distinguishable operating states which states characterizes well the driving cycle of the vehicle. The main contribution of the proposed method is that it reliably estimates the external loads which interacts the vehicle, the controller can adapt to this changes thus it can guarantee the minimal energy consumption. The vehicle described in the paper is a participant at the Shell Eco-marathon Europe competition in Urban Concept - Battery Electric category.

Open Access: Yes

DOI: 10.1115/DETC2017-67978

Impact of agricultural drought on sunflower production across hungary

Tamás Ratonyi Endre Harsányi A. Széles Muhammad Habib Ur Rahman Bashar Bashir István Bácskai Karam Alsafadi Safwan Mohammed Firas Alsilibe Csaba Juhász Abdullah Alsalman

Publication Name: Atmosphere

Publication Date: 2021-10-01

Volume: 12

Issue: 10

Page Range: Unknown

Description:

In the last few decades, agricultural drought (Ag.D) has seriously affected crop production and food security worldwide. In Hungary, little research has been carried out to assess the impacts of climate change, particularly regarding droughts and crop production, and especially on regional scales. Thus, the main aim of this study was to evaluate the impact of agricultural drought on sunflower production across Hungary. Drought data for the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI) were collected from the CAR-BATCLIM database (1961–2010), whereas sunflower production was collected from the Hungarian national statistical center (KSH) on regional and national scales. To address the impact of Ag.D on sunflower production, the sequence of standardized yield residuals (SSYR) and yield losses YlossAD was applied. Additionally, sunflower resilience to Ag.D (SRAg.D) was assessed on a regional scale. The results showed that Ag.D is more severe in the western regions of Hungary, with a significantly positive trend. Interestingly, drought events were more frequent between 1990 and 2010. Moreover, the lowest SSYR values were reported as −3.20 in the Hajdu-Bihar region (2010). In this sense, during the sunflower growing cycle, the relationship between SSYR and Ag.D revealed that the highest correlations were recorded in the central and western regions of Hungary. However, 75% of the regions showed that the plantation of sunflower is not resilient to drought where SRAg.Dx < 1. To cope with climate change in Hungary, an urgent mitigation plan should be implemented.

Open Access: Yes

DOI: 10.3390/atmos12101339