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Found 6423 publications

Application of Bivariate Extreme Value models to describe the joint behavior of temporal and speed related surrogate measures of safety

Attila Borsos

Publication Name: Accident Analysis and Prevention

Publication Date: 2021-09-01

Volume: 159

Issue: Unknown

Page Range: Unknown

Description:

Limitations of historical crash data and the advantages of surrogate measures of safety have already been stressed by various authors. To describe nearness-to-collision, mostly time-based indicators are applied, and there is a consensus among researchers that speed-related indicators are needed to account for the severity dimension. There have been attempts to fit bivariate Extreme Value models to predict the number of crashes, however modeling crash frequency together with severity has received much less attention. The aim of this paper is to apply Extreme Value models to various pairs of temporal and speed-related indicators in order to investigate the dependence structure between them as well as to construct probability based risk levels and examine them in relation to severity levels. Bivariate threshold excess models were fitted to a dataset of left-turning and straight moving vehicle interactions recorded in a signalized intersection. The dependence structure between variable pairs were thoroughly investigated; it was concluded that temporal and speed related indicators were found independent, which means that road users getting close to each other in time does not necessarily come with high speeds. Therefore these indicators should be combined in order to properly predict severity; a temporal indicator on its own is not enough to make inferences about the severity of events. Using the calculated joint probability of events risk levels were constructed illustrating the events of equal probability.

Open Access: Yes

DOI: 10.1016/j.aap.2021.106274

Course innovation in business higher education – A case study of a BA Commerce and Marketing course

Attila Kurucz Szandra Gombos

Publication Name: International Conference on Higher Education Advances

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: 448-455

Description:

This paper explores the dynamic landscape of higher education, specifically in the domain of Commerce and Marketing, over the past decade. As higher education faces evolving challenges and changing stakeholder expectations, the study delves into the ongoing debate regarding the alignment of higher education, including business education on a Commerce and Marketing BA course in West-Hungary. The research employs a comprehensive case study methodology spanning ten academic years to showcase the course's development and innovations. The study scrutinizes changes in teaching methodologies, course materials, seminar and project assignments, applied technologies, and assessment methods. Findings from in-depth interviews with business professionals, and student observations reveal the course's adaptation to market needs and challenges encountered during the online transition. The results suggest that, despite disruptions in the academic year 20/21 due to the COVID-19 pandemic, the development of this course in the examined years successfully aligns with market expectations, fostering competencies essential for the business domain, thanks to introducing new methodologies (interactive project-based, seminars), usage of AI assisted applications, and introducing new forms of assessments.

Open Access: Yes

DOI: 10.4995/HEAd24.2024.17347

Determination of power and torque curves of electric driven vehicles based on diagnostic methods

István Lakatos Dávid Czeglédi Dániel Pup

Publication Name: Proceedings of the ASME Design Engineering Technical Conference

Publication Date: 2015-01-01

Volume: 9

Issue: Unknown

Page Range: Unknown

Description:

The transmitted power of motors can be defined by test bench examinations, in which the motor needs to be dismounted. By applying diagnostic methods only minimal disassembly, or indeed none at all, is necessary. In this paper diagnostic methods are systematized by different studies. Moreover, a new diagnostic procedure (established by the authors) is also introduced, which can be carried out by a relatively cheap measuring system design. Power measurement on a roller test bench is a well-Tried technique for vehicle examination. Basically, the wheel parameters (tractive force, torque, power) are measured, but there are also procedures for motor power measurement. By applying the new procedure, the diagnostic method, (simple construction and test bench construction at a favourable price) torque and power characteristics of the mounted motor can be defined. The theoretical considerations of the new measuring technique and the implementation of the measuring system are introduced in this paper. Test bench for drive motor power and torque curve determination. In this study the diagnostical measuring systems and, for the first time, the measuring principle and technology of the new theorybased roller power test bench are presented. For its construction measurements have been carried out which make an important contribution to the research. The results of the research contribute to the development of diagnostics methods and to making them more wide-spread.

Open Access: Yes

DOI: 10.1115/DETC2015-46724

Carbon accounting measurement with digital non-financial corporate reporting and a comparison to european automotive companies statements

Szigeti Cecília Árpád Tóth Alex Suta

Publication Name: Energies

Publication Date: 2021-09-01

Volume: 14

Issue: 18

Page Range: Unknown

Description:

The regulatory environment for both sustainability and financial reporting is changing as standardisation and digital reporting (e.g., XBRL) are gaining traction within regulators. The measurement methodology and mandatory information content of disclosures are yet to be decided for corporate CO2 reporting by EU regulators and standard-setting organisations. In our study, we reviewed the sustainability reports of three leading German automotive groups by revenue for the period 2016–2020 as a case study. The research methodology was carried out with text-mining-aided content analysis to provide a collection of sustainability standards (GRI and SASB) in the evaluation of emissions reporting. As an addition to prior literature, conditions of relevance and clarity regarding published information were introduced in the evaluation process of compliance to CO2 disclosures. Companies by reporting practice were assigned to different stages of carbon management and actual emissions were evaluated. In the conclusions, discussion of the reliability of reported sustainability information, the applicability of digital reporting is provided through regional perspectives. We found that although analytical methods are available to assess the level of corporate carbon management, their usefulness is limited if the data are not reliable. Significant progress can be expected from analyses using standardised, comparable corporate carbon data.

Open Access: Yes

DOI: 10.3390/en14185607

Special reinforcement solutions of railway permanent ways’ soil substructures

Muayad Habashneh

Publication Name: Acta Technica Jaurinensis

Publication Date: 2021-08-25

Volume: 14

Issue: 3

Page Range: 339-363

Description:

This mini review aims to summarize relevant international publications. Thus, based on this, giving a comprehensive review about the reinforcement solutions of permanent ways' soil substructure. Generally, the core weakness of soil is its inadequacy to resist tensile stresses. The main target of strengthening the soil is to enhance the engineering characteristics of the soil to build up specific parameters such as shear strength, compressibility, density, and hydraulic conductivity. In addition, special reinforcement techniques of railway permanent ways' soil substructures will be considered in this paper due to the increasing demand of improving railways and rehabilitation process. The main findings of this study that there are a lot of special reinforcement techniques which can be considered as effective solution for soil stabilization such as geosynthetic reinforcement.

Open Access: Yes

DOI: 10.14513/actatechjaur.00612

Dynamic Analysis of Geosynthetic-reinforced Pile-supported Embankment for a High-Speed Rail

Edina Koch Rashad Alsirawan

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2024-01-01

Volume: 21

Issue: 1

Page Range: 31-50

Description:

Geosynthetic-Reinforced-Pile-Supported (GRPS) embankments are a trustworthy option ideal to support the railways over soft soils. They are widely used for the time-bound infrastructure projects. The majority of earlier research concentrated on the analysis of the GRPS embankments under static loads while the studies on the behavior of these constructions under dynamic loads are scarce. The fundamental purpose of this study has been to better comprehend the dynamic behavior of GRPS embankments in terms of stresses and settlements distribution via 3D modeling employing the finite element method (FEM). The advanced constitutive model of Hardening soil with small-strain stiffness was utilized to simulate the behavior of the soils under dynamic loads and the train load was modeled according to the recommendations of LM71 Eurocode. The results indicate to the contribution of the piles and geosynthetic reinforcement in the decrease of the settlements. The behavior of settlements and stresses under static and dynamic loads is similar. The load efficiency of the piles decreases during the passage of the train remarkably. The train speed affects obviously on the behavior of the GRPS embankment.

Open Access: Yes

DOI: 10.12700/APH.21.1.2024.1.3

Concepts and Examples of Carbon-Free, Self-Sufficient Local Energy Systems

Balázs Vehovszky Zoltán Weltsch Ferenc Magyar Lóránt Kovács

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 931-936

Description:

The necessity of the “green revolution” in the field of energetics is not a question anymore; however, switching the current fossil fuel-based energy ecosystem to a fully renewable-based one poses enormous challenges. The historical structure of the present, centralised energy production infrastructure, as well as the fundamentally different characteristics of the three main fields of usage (electricity generation, heating and transportation), are among the most substantial hindering factors. The future energy system has to be much more flexible in several respects, with a fundamental contribution of smaller, independent energy communities. The current study focuses on the realisation aspects of such a small-scale energy community (or micro/nano-grid), considering the suitable technological solutions as well as the cost concerns. A high number of pilot projects and case studies around the world prove that the technical feasibility of a local grid/energy community is no longer a question. The real challenge is to find the appropriate incentives and strategy to catalyse the required transition at the legislation, system operator and end-user level as well. The outcomes of the present work contribute to this goal by pointing out the application potentials of a modular, scalable microgrid system based on a currently running microgrid-realization project at the ZalaZONE proving ground.

Open Access: Yes

DOI: 10.3303/CET24114156

A CROSS-COUNTRY STUDY ON THE DETERMINANTS OF WORKING CAPITAL MANAGEMENT: GMM APPROACH

Laszlo Vasa Simona Andreea Apostu Ploypailin Kijkasiwat Anwar Hussain

Publication Name: Transformations in Business and Economics

Publication Date: 2022-01-01

Volume: 21

Issue: 3

Page Range: 288-305

Description:

The paper analyzed the determinants of Working Capital Management (WCM) of listed manufacturing firms across South Asian Association of Regional Corporation (SAARC) countries from 2000 to 2020. Employing a Generalized Method of Moments, we found that operational risk and market risk are key hurdles to efficient working capital management. Our results are providing an important managerial implication for the use of operational risk and market risk in selected countries. Firms in selected countries can manage an optimal level of WCM through controlling operational risk and market risk, therefore should develop a ranking system about WCM activities to boost up their firm value.

Open Access: Yes

DOI: DOI not available

Prediction of fullerene stability using topological descriptors

Eniko Bitay Tamás Réti

Publication Name: Materials Science Forum

Publication Date: 2007-01-01

Volume: 537-538

Issue: Unknown

Page Range: 439-448

Description:

In recent years, several attempts have been made to characterize the geometric structure of fullerenes by means of topological shape factors in order to predict their physical properties and stability. In this paper, we present a simple method to estimate the stability of fullerenes on the basis of quantitative topological criteria. This approach is based on the concept of the generalized combinatorial curvatures defined on the set of simple graphs embedded on a closed surface without boundary (sphere, torus, projective plane, Klein bottle). It is shown that starting with the computed generalized combinatorial curvatures several novel topological indices can be generated. From computations performed on a set of C40 and C60 fullerenes, we concluded that the four topological shape factors tested (Λ(-1), Ω(-1), Λ(1) and Ω(1)) could be successfully used to preselect the most stable fullerene isomers.

Open Access: Yes

DOI: 10.4028/0-87849-426-x.439