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Found 6407 publications

Segmentation of a road vehicle vibration signal using multiple comparison procedures between paired samples

László Róbert Hári

Publication Name: Tehnicki Vjesnik

Publication Date: 2021-08-01

Volume: 28

Issue: 5

Page Range: 1597-1604

Description:

Segmentation of road vehicle vibration (RVV) signals can occur by the need to analyse or synthesise vibrations obtained in passenger cars or on the stowage of vans, trucks. A general and widely used measure to quantify RVV signals is its description via power spectral density (PSD). From a given PSD a Gaussian signal can be generated in a shaker testing laboratory. However, actual RVVs tend to have a non-Gaussian and nonstationary nature, which can be modelled as a composition of different segments, each with a different length and RMS content. For simulation purposes of nonstationary vibration signals, different approaches have been introduced yet each with its unique signal segmentation approaches. The current paper proposes a signal segmentation method implemented in the time-frequency domain in order to find segments within an RVV signal, where each segment has similarity in-between and is dissimilar to neighbouring segments. For this purpose, multiple comparison tests had been utilised between the Short-time Fourier transforms (STFT) applied on given fractions of an RVV. Different countermeasures had been applied against the Type I. error inflation.

Open Access: Yes

DOI: 10.17559/TV-20200122112551

From complexity & research to cleanliness: The synergy of R&D investments, EV technologies and green complexity for sustainability

Laszlo Vasa Irum Shahzadi Yuriy Bilan Zuchang Zhong Muhammad Adnan Bashir Irum Shahzadi

Publication Name: International Review of Economics and Finance

Publication Date: 2026-01-01

Volume: 105

Issue: Unknown

Page Range: Unknown

Description:

The developed and emerging countries strive for sustainability and focus on enhancing greener energy and electric products. Adopting electric vehicles and utilizing green energy sources are essential to this objective. This study examines the synergy between EV technologies, green energy, and sustainability in China using quarterly data from 2010Q1 to 2022Q4. In addition, it considers the policy-level roles of economic complexity and research and development efforts in the EV industry. The authors employ novel time-series methods to assess long-term associations, including unit root testing, the Bayer-Hanck cointegration test, FMOLS, and DOLS. Robustness is checked using both a parametric method (least squares with breaks) and a non-parametric method (quantile regression). The empirical results reveal that electric vehicle technologies, economic complexity, and R&D expenditures exert an unfavorable effect on greenhouse gas emissions. By contrast, green energy and economic globalization significantly reduce ecological emissions in the long run. The robustness check analysis through parametric and non-parametric provides robust and valid outcomes. Promoting the adoption of electric vehicles and investing in green energy, and research & development intiaitves have significant policy implications for attaining environmental sustainability. lastly, enhancing economic complexity and fostering economic globalization should be considered to ensure a stable environment and facilitate sustainable development and better environmental quality.

Open Access: Yes

DOI: 10.1016/j.iref.2025.104743

Robustness of fuzzy flip-flop based neural networks

László Gál Rita Lovassy Laszlo T. Koczy

Publication Name: 11th IEEE International Symposium on Computational Intelligence and Informatics Cinti 2010 Proceedings

Publication Date: 2010-12-01

Volume: Unknown

Issue: Unknown

Page Range: 207-211

Description:

In this paper the robustness of three different types of Fuzzy Flip-Flop based Neural Network (FNN) and the standard tansig based neural networks is compared from the various test function approximation goodness points of view. It is tested how well the fuzzy flip-flop based and the simulated neural networks handle the test data sets outlier points. The robust design of the FNN is presented, and the best suitable fuzzy neuron type is emphasized. Furthermore, the sensitivity of fuzzy neural networks to the fuzzy neuron type and hidden layers neuron number is evaluated. ©2010 IEEE.

Open Access: Yes

DOI: 10.1109/CINTI.2010.5672248

Remanufacturing a Synchronous Reluctance Machine with Aluminum Winding: An Open Benchmark Problem for FEM Analysis

Miklós Kuczmann Mihaly Katona Tamas Orosz Zoltan Nemeth Dávid Gábor Bányai

Publication Name: Electronics Switzerland

Publication Date: 2024-02-01

Volume: 13

Issue: 4

Page Range: Unknown

Description:

The European Union’s increasing focus on sustainable and eco-friendly product design has resulted in significant pressure on original equipment manufacturers to adopt more environmentally conscious practices. As a result, the remanufacturing of end-of-life electric machines is expected to become a promising industrial segment. Identifying the missing parameters of these types of machines will play an essential role in creating feasible and reliable redesigns and remanufacturing processes. A few case studies related to this problem have been published in the literature; however, some novel, openly accessible benchmark problems can facilitate the research and function as a basis for comparing and validating novel numerical methods. This paper presents the identification process of an experimental synchronous machine. It outlines methodologies for identifying material properties, winding schemes, and other critical parameters for the finite element analysis and modelling of electric machines with incomplete information. The machine in question is intended for remanufacturing, with the plan to replace its faulty winding with an aluminium-based alternative. It also serves as an open benchmark problem for researchers, designers, and practitioners.

Open Access: Yes

DOI: 10.3390/electronics13040727

Comparative study on credibility measures of type-2 and type-1 fuzzy variables and their application to a multi-objective profit transportation problem via goal programming

Dipak Kumar Jana Palash Sahoo Laszlo T. Koczy

Publication Name: International Journal of Transportation Science and Technology

Publication Date: 2017-06-01

Volume: 6

Issue: 2

Page Range: 110-126

Description:

In real world applications supply, demand and transportation costs per unit of the quantities in multi-objective transportation problems may be hardly specified accurately because of the changing economic and environmental conditions. It is also significant that the time required for transportation should be minimized. In this paper, we have presented three reduction methods for a type-2 triangular fuzzy variable (T2TrFV) by adopting the critical value (CV). Three generalized expected values (optimistic, CV and pessimistic) are derived for T2TrFVs with some special cases. Then a multi-objective profit transportation problem (MOPTP) with fixed charge (FC) cost has been formulated and solved in type-2 fuzzy environment. Unit transportation costs, FC, selling prices, unit transport times, loading and unloading times, total supply capacities and demands are all considered as triangular Type-2 fuzzy numbers. The MOPTP has been converted into a single objective by using the goal programming technique and the weighted sum method. The deterministic model is then solved using the Generalized Reduced Gradient method Lingo 14.0. Numerical experiments with some sensitivity analysis are illustrated the application and effectiveness of the proposed approaches.

Open Access: Yes

DOI: 10.1016/j.ijtst.2017.06.002

Polyaromatic hydrocarbons (PAHs) in the water environment: A review on toxicity, microbial biodegradation, systematic biological advancements, and environmental fate

Mahmoud Nasr Balasubramani Ravindran Abiraami Ramakrishnan Praveen Kumar Issac Kuan Shiong Khoo Nur Izyan Wan Azelee Babett Greff Rajinikanth Rajagopal Byong Hun Jeon Madhumitha Vijayanand Ramakrishnan Subramanian Soon Woong Chang

Publication Name: Environmental Research

Publication Date: 2023-06-15

Volume: 227

Issue: Unknown

Page Range: Unknown

Description:

Polycyclic aromatic hydrocarbons (PAHs) are considered a major class of organic contaminants or pollutants, which are poisonous, mutagenic, genotoxic, and/or carcinogenic. Due to their ubiquitous occurrence and recalcitrance, PAHs-related pollution possesses significant public health and environmental concerns. Increasing the understanding of PAHs' negative impacts on ecosystems and human health has encouraged more researchers to focus on eliminating these pollutants from the environment. Nutrients available in the aqueous phase, the amount and type of microbes in the culture, and the PAHs' nature and molecular characteristics are the common factors influencing the microbial breakdown of PAHs. In recent decades, microbial community analyses, biochemical pathways, enzyme systems, gene organization, and genetic regulation related to PAH degradation have been intensively researched. Although xenobiotic-degrading microbes have a lot of potential for restoring the damaged ecosystems in a cost-effective and efficient manner, their role and strength to eliminate the refractory PAH compounds using innovative technologies are still to be explored. Recent analytical biochemistry and genetically engineered technologies have aided in improving the effectiveness of PAHs' breakdown by microorganisms, creating and developing advanced bioremediation techniques. Optimizing the key characteristics like the adsorption, bioavailability, and mass transfer of PAH boosts the microorganisms' bioremediation performance, especially in the natural aquatic water bodies. This review's primary goal is to provide an understanding of recent information about how PAHs are degraded and/or transformed in the aquatic environment by halophilic archaea, bacteria, algae, and fungi. Furthermore, the removal mechanisms of PAH in the marine/aquatic environment are discussed in terms of the recent systemic advancements in microbial degradation methodologies. The review outputs would assist in facilitating the development of new insights into PAH bioremediation.

Open Access: Yes

DOI: 10.1016/j.envres.2023.115716

An Investigation of the Recent Developments in Reliability-based Structural Topology Optimization

Majid Movahedi Rad Muayad Habashneh

Publication Name: Periodica Polytechnica Civil Engineering

Publication Date: 2023-06-16

Volume: 67

Issue: 3

Page Range: 765-774

Description:

Optimizing a structure's topology involves finding the best possible distribution of material and connections within a given design space. It has a significant effect on its performance, which is why there has been a meteoric rise in the number of articles published on the topic over the last two decades. This work offers an investigation of reliability-based topology optimization of structures, in light of the recent development of several topology optimization techniques for both linear and nonlinear systems. Therefore, the emphasis of this study is on the latest advancements, enhancements, and applications of reliability-based topology optimization. This paper's primary objective is to provide an overview of the latest advancements in the reliability-based topology optimization of structures, with a particular emphasis on the recent improvement of integrating reliability-based design into the bi-directional evolutionary structural optimization (BESO) method, which accounts for the topological optimization of geometric and material nonlinearity as well as thermoelastic problems.

Open Access: Yes

DOI: 10.3311/PPci.22107

Simulation of the Turning Assistant in Road Traffic Accident Reconstruction

Dániel Feszty Gyula Kőfalvi I. Lakatos Ferenc Ignácz Andreas Moser

Publication Name: Future Transportation

Publication Date: 2026-02-01

Volume: 6

Issue: 1

Page Range: Unknown

Description:

The accurate simulative reconstruction of blind spot accidents requires innovative simulation methods. The objective of this paper is to analyze the avoidability of a specific blind spot accident and assess the impact of various parameters as if an active turning assistant had been installed in the truck. Additionally, it proposes a novel adaptation of the turning assistant system, along with an adapted simulation model tailored for drawbar trailers. The analyses presented in this paper were performed using PC-Crash accident simulation software, applying the “Active Safety” module. After performing a simulation of an accident involving a right-turning truck with a center axle trailer and a pedestrian, the avoidability of the accident was examined by simulating the scenario as if the truck involved in the accident had been equipped with an active turning assistant system. Subsequently, a parameter analysis was conducted to analyze the effect of changes in the active turning assistant’s parameters and changes in the pedestrian’s direction of entry on the avoidability of the accident. In doing so, we determined the parameters for the worst-case (collision) and the best-case (no collision) scenarios. Finally, an adaptation and further development of the active turning assistant, along with a corresponding simulation method for drawbar trailers, are proposed.

Open Access: Yes

DOI: 10.3390/futuretransp6010013

Experimental Wear Analysis of Nano-Sized Titania Particles as Additives in Automotive Lubricants

D. Tóth I. Szabó Hebah Abdallah Hajnalka Hargitai

Publication Name: Micro

Publication Date: 2023-09-01

Volume: 3

Issue: 3

Page Range: 715-727

Description:

This study focuses on the wear effects of nano-sized titania as a potential engine lubricant additive. Titanium dioxide nanoparticles have promising wear-reducing properties and significant tribological potential. In this article, titania nanoparticles were homogenized in Group III automotive oil at five different concentrations (0.1; 0.2 … 0.5 wt%). The nanodoped oil samples were tested on a linear oscillating tribometer with oil circulation. Based on the tribological results, titania nanoparticles increased friction by 20–32% but can reduce the wear area by up to 32%. According to the confocal microscopic examination, wear volume can be reduced by up to 57% with titania nanoparticles. Titania nanoparticles improved the repeatability of tribological measurements. A scanning electron microscopy examination of the wear track revealed that the characteristic wear of the tribological system was abrasive, but a significant amount of adhesive wear was also observed. Energy dispersive X-ray spectroscopy analysis found that the nanoparticles fill the deeper trenches of the wear. The worn surface uniformly contains TiO2 particles and the quantified normalized titanium concentration was between 0.56 and 0.62%.

Open Access: Yes

DOI: 10.3390/micro3030050