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Publications - 6374

Examining the links between logistics outsourcing, company competitiveness and selected performances: the evidence from an emerging country

Innocent Senyo Kwasi Acquah Yaw Agyabeng-Mensah Ebenezer Afum Joseph Amponsah Owusu Essel Dacosta Charles Baah Clifford Sekyere Owusu

Publication Name: International Journal of Logistics Management

Publication Date: 2021-01-01

Volume: 32

Issue: 3

Page Range: 1068-1090

Description:

Purpose: This study examines the mediation effects of time-based competitiveness, cost-based competitiveness and customer performance between logistics outsourcing and financial performance. Design/methodology/approach: The study relied on a questionnaire as the primary data collection instrument and further employed partial least squares structural equation modelling technique to test all formulated hypotheses. Findings: The results demonstrate that logistics outsourcing has a significant positive impact on time-based competitiveness, cost-based competitiveness, customer performance and financial performance. Time-based competitiveness and cost-based competitiveness were both found to have a significant positive impact on financial performance; however, customer performance had no significant impact on financial performance. The mediation analysis further indicates that while both time-based competitiveness and cost-based competitiveness play mediation effects between logistics outsourcing and financial performance, customer performance plays no mediation effect between logistics outsourcing and financial performance. Research limitations/implications: The sampled firms for this study came from a single emerging country; hence, the results cannot be generalized or imported to reflect the results that may be obtained from other emerging geographical settings. Practical implications: The results provide sufficient evidence for managers to turn their attention to logistics outsourcing, as a transformative business initiative, to gain time-based and cost-based competitiveness so as to improve financial performance. Originality/value: The study provides significant insight and makes an additional contribution to literature in the area of logistics outsourcing, especially by collecting data from an emerging country. Modelling time-based competitiveness, cost-based competitiveness and customer performance as mediating variables between logistics outsourcing and financial performance make this work relatively different from other studies.

Open Access: Yes

DOI: 10.1108/IJLM-05-2020-0205

Molecular dynamics simulation of carbon nanostructures: The D5h C70 fullerene

Ibolya Zsoldos István László

Publication Name: Physica E Low Dimensional Systems and Nanostructures

Publication Date: 2014-02-01

Volume: 56

Issue: Unknown

Page Range: 422-426

Description:

Molecular dynamics calculations can reveal the physical and chemical properties of various carbon nanostructures or can help to devise the possible formation pathways. In our days the most well known carbon nanostructures are the fullerenes and the nanotubes. They can be thought of as being formed from graphene sheets, i.e. single layers of carbon atoms arranged in a honeycomb lattice. Usually the nature does not follow the mathematical constructions. An ideal nanotube can be thought of as a hexagonal network of carbon atoms that has been rolled up to make a cylinder. There is not any theory of carbon nanotube formation which is based on this construction. Although the first time the C60 and C70 were constructed by laser irradiated graphite, the fullerene formation theories are based on various fragments of carbon chains, and networks of pentagonal and hexagonal rings. In the present article different initial patterns will be given for the formation of the C70 fullerene with D5h symmetry. The desired final structures are obtained in tight-binding molecular dynamics calculations. © 2013 Published by Elsevier B.V.

Open Access: Yes

DOI: 10.1016/j.physe.2012.08.009

A Long Short-Term Memory-Based Deep Learning Digital Twin of a Li-Ion Cell for Battery SOC Estimation †

József Richárd Lennert Denes Fodor

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

This study aims to implement the digital twin of a Li-ion battery by using real measurement data and to create a deep learning-based SOC (state of charge) estimation solution. In the case of the SOC estimator, a special type of deep learning, so-called long short-term memory (LSTM), was used to increase the capabilities of the estimator. The digital twin and the SOC estimator were created by using MATLAB and MATLAB/Simulink. As a result, the implemented system can accurately simulate the non-linearities of the Li-ion battery and provide a satisfactory estimation of the SOC of the battery.

Open Access: Yes

DOI: 10.3390/engproc2024079016

Heat Characteristics and Emission Effect of a Fuel-operated Auxiliary Air Heater Fed with Fuel E10, E30 and E100

Ibolya Zsoldos György Szabados Péter Nagy

Publication Name: Periodica Polytechnica Mechanical Engineering

Publication Date: 2024-01-01

Volume: 68

Issue: 2

Page Range: 181-186

Description:

In order to increase the comfort of vehicle passengers in specific vehicle categories, the heating of the passenger compartment is not provided by the heat from the engine driving the vehicle but by an additional heating device. The study examines the effect of auxiliary heaters that use liquid fuels to heat the passenger compartment of vehicles. The device was operated during the test with two different mixtures containing bioethanol (E30, E100) and the original motor gasoline (E10). It aimed to understand the effects of different fuels, particularly heating performance, operating time and emissions. Based on the results, as the ethanol content increases, the temperature of the device’s flame and heating air decreases. The experiments showed that in the case of E100 bioethanol, the average temperature measured in stable operating conditions was significantly lower than in the case of E10 motor gasoline. That suggests that an increase in the ethanol content reduces the heating performance. Another significant result of the study was that in the case of mixtures containing ethanol, a longer operating time is required to achieve the same amount of heat, which leads to additional fuel consumption. In addition, when using E100 bioethanol, the amount of harmful gases that are emitted increases significantly during the longer operating time. This observation can be important for evaluating the environmental impact and efficiency of vehicles.

Open Access: Yes

DOI: 10.3311/PPme.36911

Optimization of damping pad distribution on body-in-white car structure

Dániel Feszty Marcell Treszkai David Sipos

Publication Name: Journal of Vibroengineering

Publication Date: 2022-01-01

Volume: 24

Issue: 2

Page Range: 386-393

Description:

Structure-born noise is one of the most important contributors to the interior noise in a vehicle cabin. This can be effectively reduced by placing damping pads with special material properties along the chassis and on the large, radiating panels. This paper proposes a new methodology for the optimization of placing these pads as a part of a full vehicle acoustic simulation in Actran Virtual SEA. With this new strategy, it was possible to reduce the among of damping pads on a real car structure by 33 % while keeping the same acoustic performance. This was validated by investigating the mean velocity of the floor panel in two load cases and compared to the original damping pad layout to the optimized one.

Open Access: Yes

DOI: 10.21595/jve.2021.22158

Curvature-Constrained Motion Planning Method for Differential-Drive Mobile Robot Platforms

Áron Ballagi Rudolf Krecht

Publication Name: Applied Sciences Switzerland

Publication Date: 2026-01-01

Volume: 16

Issue: 1

Page Range: Unknown

Description:

Compact heavy-duty skid-steer robots are increasingly used for city logistics and intralogistics tasks where high payload capacity and stability are required. However, their limited maneuverability and non-negligible turning radius challenge conventional waypoint-tracking controllers that assume unconstrained motion. This paper proposes a curvature-constrained trajectory planning and control framework that guarantees geometrically feasible motion for such platforms. The controller integrates an explicit curvature limit into a finite-state machine, ensuring smooth heading transitions without in-place rotation. The overall architecture integrates GNSS-RTK and IMU localization, modular ROS 2 nodes for trajectory execution, and a supervisory interface developed in Foxglove Studio for intuitive mission planning. Field trials on a custom four-wheel-drive skid-steer platform demonstrate centimeter-scale waypoint accuracy on straight and curved trajectories, with stable curvature compliance across all tested scenarios. The proposed method achieves the smoothness required by most applications while maintaining the computational simplicity of geometric followers. Computational simplicity is reflected in the absence of online optimization or trajectory reparameterization; the controller executes a constant-time geometric update per cycle, independent of waypoint count. The results confirm that curvature-aware control enables reliable navigation of compact heavy-duty robots in semi-structured outdoor environments and provides a practical foundation for future extensions.

Open Access: Yes

DOI: 10.3390/app16010322

The Legal Status of Independent Regulatory Organs and Their Place in the Hungarian State Administration

János Kálmán

Publication Name: Public Governance Administration and Finances Law Review

Publication Date: 2023-01-01

Volume: 8

Issue: 1

Page Range: 105-119

Description:

Independent regulatory organs as a type of administrative body were included among the central state administrative bodies upon the entry into force of the Fundamental Law of Hungary. The key feature of independent regulatory organs is that they also have the power to legislate within the framework of the regulatory authority’s activity; in other words, they can intervene in the relations of their administered sector through the creation of generally binding rules of conduct, which are enforced through the official activities falling within their scope of duties and powers. The characteristics of the legal status of independent regulatory organs and the components of their independence are therefore of particular importance in the system of public administration. The content and strength of their independence are not identical but are adapted to the professional content and EU and constitutional requirements of the specialised area of administration for which the Fundamental Law authorises the National Assembly to establish these bodies.

Open Access: Yes

DOI: 10.53116/pgaflr.6561

COMPARATIVE ANALYSIS OF THE ENVIRONMENTAL IMPACT OF STEEL AND REINFORCED CONCRETE HALL STRUCTURES

János Szép Kitti Karolyfi

Publication Name: Iet Conference Proceedings

Publication Date: 2024-01-01

Volume: 2024

Issue: 8

Page Range: 65-71

Description:

The examination of the environmental impact of buildings during the design process is becoming increasingly important nowadays. Since the geometry and materials of the building are chosen during the conceptual design phase, it is of paramount importance to explore alternative solutions during this stage, considering their significant effect on the building’s environmental footprint and performance later. The aim of this study is to compare the environmental impact of an industrial hall depending on the applied structural material and geometry. 48 different geometries were generated and evaluated using parametric design focusing on the first stage of the lifecycle. Regarding the material of the load-bearing structure, the prefabricated reinforced concrete hall exhibits a lower overall environmental impact compared to the steel structure of the same geometry. In terms of geometry, among the three spans examined (16.5, 18, and 20 meters), the largest span proves to be the most environmentally advantageous.

Open Access: Yes

DOI: 10.1049/icp.2024.2683

Digital services of tourist areas—Key to competitiveness

Eva Happ Marcell Kupi Zsuzsanna Ivancsóné Horváth

Publication Name: Journal of Infrastructure Policy and Development

Publication Date: 2024-01-01

Volume: 8

Issue: 6

Page Range: Unknown

Description:

In our study, we examined 11 designated tourist destinations in Hungary, which can also be interpreted as tourism products including services, infrastructure and attractions. The National Tourism Development Strategy (NTS) also puts a strong emphasis on digitalisation, as it is an unstoppable process with a significant impact on tourism, thanks to globalisation, increasing competition, accelerating information flows and the dominant paradigm shifts on the demand and supply side. We used both qualitative and quantitative methods in our primary research. First, we conducted in-depth interviews with several important tourism service providers in Hungary on the topic of the digitalisation of tourism. A professional questionnaire, addressed to the offices responsible for destination management was distributed in the designated tourist destinations in Hungary in order to get a more comprehensive picture of the attitudes towards digitalisation in the regions under study. In the course of our work, we managed to classify the destinations into three distinctly different clusters. Our hypothesis—that the higher the digitalisation of a tourist destination is, the higher the average length of stay—was partially confirmed by calculating the regional value of the digitalisation, logistic regression analysis, slope and the individual factor categories.

Open Access: Yes

DOI: 10.24294/JIPD.V8I6.3912