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Found 6327 publications

P-graphs for process systems engineering: Mathematical models and algorithms

Ákos Orosz Jean Pimentel Losada Ferenc Friedler

Publication Name: P Graphs for Process Systems Engineering Mathematical Models and Algorithms

Publication Date: 2022-02-03

Volume: Unknown

Issue: Unknown

Page Range: 1-261

Description:

This book discusses the P-graph framework for developing and understanding effective design tools for process systems engineering, and addresses the current state of its theory and applications. The book details the new philosophy of the axioms-based mathematical modelling of processing systems, the basic algorithms, areas of application, future directions, and the proofs of theorems and algorithms. Because of the rigorous foundation of the theory, the framework provides a firm basis for future research in mathematical modelling, optimization, and design of complex engineering systems. The various P-graph applications discussed include process network synthesis, reliability engineering, and systems resilience. The framework opens new avenues for research in complex systems including redundant operations for critical infrastructure, systems sustainability, and modelling tools for disaster engineering. Demonstration software is provided to facilitate the understanding of the theory. The book will be of interest to institutions, companies, and individuals performing research and R&D in process systems engineering.

Open Access: Yes

DOI: 10.1007/978-3-030-92216-0

How to Vary the Input Space of a T-S Fuzzy Model: A TP Model Transformation-Based Approach

Peter Baranyi

Publication Name: IEEE Transactions on Fuzzy Systems

Publication Date: 2022-02-01

Volume: 30

Issue: 2

Page Range: 345-356

Description:

The motivation behind 15 years of continuous development within the topic of the tensor product (TP) model transformation is that the greater the number of parameters or components of the Takagi-Sugeno (T-S) fuzzy model one can manipulate, the larger complexity reduction or control optimization one can achieve. This article proposes a radically new type of extension to the TP model transformation. While earlier variants of the TP model transformation focused on how the antecedent - consequent fuzzy set system of a given T-S fuzzy model could be varied, this article, in contrast, focuses on how the number of inputs to a given T-S fuzzy model can be manipulated. The proposed extension is capable of changing the number of inputs or transforming the nonlinearity between the fuzzy rules and the input dimensions. These new features considerably increase the modeling power of the TP model transformation, allowing for further complexity reduction and more powerful control optimization to be achieved. This article provides two examples to show how the proposed extension can be used in a routine-like fashion.

Open Access: Yes

DOI: 10.1109/TFUZZ.2020.3038488

Tribological Properties of the Nanoscale Spherical Y2O3 Particles as Lubricant Additives in Automotive Application

Rajmund Kuti Máté Zs Leskó D. Tóth J. Rohde-Brandenburger I. Szabó

Publication Name: Lubricants

Publication Date: 2022-02-01

Volume: 10

Issue: 2

Page Range: Unknown

Description:

The continuous tribological development of engine lubricants is becoming more and more vital due to its fuel efficiency improvement and lifetime increasing potential. The antiwear additives play a high role in the lubricants to protect the contacting surfaces even in the presence of thinner oil film. Nanoscale spherical particles in the lubricant may increase the necessary protecting effect. This paper presents the results of the experimental tribological investigation of nanoscale spherical Y2O3 (yttria) ceramic particles as an engine lubricant additive. The ball-on-disc tribological measurements have revealed an optimum concentration at 0.5 wt% with about 45% wear scar diameter and 90% wear volume decrease, compared to the reference, neat Group III base oil. The high-magnitude SEM analysis revealed the working mechanisms of yttria: the particles collected in the roughness valleys resulted in a smoother contacting surface, they were tribo-sintered and they have also caused slight plastic deformation of the outer layer of the metallic surface.

Open Access: Yes

DOI: 10.3390/lubricants10020028

Impact of Autonomous Vehicles on Roundabout Capacity

Csaba Koren Attila Borsos Viktor Nagy Othmane Boualam

Publication Name: Sustainability Switzerland

Publication Date: 2022-02-01

Volume: 14

Issue: 4

Page Range: Unknown

Description:

Studying the impact of AVs on our road infrastructure offers a lot of potential in the transportation domain; one of these issues is how capacity will be affected. This paper presents a contribution to this research area by investigating the impact of AVs on the capacity of single-lane roundabouts using a microsimulation model. For the development of the model, a roundabout situated in Győr (Hungary) was selected and field data on the roundabout geometric characteristics as well as traffic volumes were used. Simulations using Vissim were run for various scenarios based on varying input traffic volumes and market penetration rates of AVs to assess queue lengths. The highway capacity manual (HCM) roundabout model was used to estimate the capacity of the existing roundabout. Values of follow-up times and critical gaps were set to decreasing as the penetration rate of AVs increases. The results demonstrated that 20% and 40% AVs in the flow would increase leg capacities by about 10% and 20%, respectively. Furthermore, a reduction in excessive queue lengths was estimated and capacities and queue lengths were calculated by legs. It was found that these are highly influenced by the distribution of flows among legs, and the share of flows in various directions.

Open Access: Yes

DOI: 10.3390/su14042203

Gender-specific pathways regarding the outcomes of a cyberbullying youth education program

Helga Judit Feith Máté Kapitány-Fövény Johanna Takács J. Ágnes Lukács István Kitzinger Gábor Szabó András Falus Zsuzsanna Soósné Kiss

Publication Name: Personality and Individual Differences

Publication Date: 2022-02-01

Volume: 186

Issue: Unknown

Page Range: Unknown

Description:

Introduction: Marked gender differences have been identified in cyberbullying perpetration and victimization in adolescence. Age and phenotypic traits, including impulsivity and problematic internet use may mediate the association between gender and cyberbullying intervention outcomes. This study thus aimed to explore gender differences and the potential mediating role of age, impulsivity and problematic internet use regarding the outcomes of an elementary school cyberbullying program. Methods: The peer-led STAnD project shapes students' attitudes towards cyberbullying, and promotes help-seeking behaviors. Baseline sample consisted of 933 respondents (51.3% females, mean age = 11.25, sd = 1.64), and after a 42.55% drop-out, 536 remained in the sample for 6-month follow-up. Four primary outcome measures represented protective factors against cyberbullying. Results: Three of the intervention outcomes – change in 1) helpline knowledge, 2) empathy towards the victims of cyberbullying, and 3) risk perception regarding online hazards - were best predicted by gender. A gender-specific path analysis model indicated that higher amount of time spent online might put a barrier to changes in risk awareness among females and in help-seeking willingness among males. Conclusions: Future cyberbullying programs may design separate interventions for adolescent boys and girls with different emphasis placed on empathy training, or the barriers to help-seeking.

Open Access: Yes

DOI: 10.1016/j.paid.2021.111338

Permanent Magnet Synchronous Motor Model Extension for High-Frequency Signal Injection-Based Sensorless Magnet Polarity Detection

Krisztian Enisz Istvan Szalay Hunor Medve Denes Fodor

Publication Name: Energies

Publication Date: 2022-02-01

Volume: 15

Issue: 3

Page Range: Unknown

Description:

In this paper, a novel extended permanent magnet synchronous motor model is presented that incorporates a quadratic flux-current function to represent the polarity-dependent saliency. The proposed model enables the design of sensorless polarity detection algorithms required by the initial position detection of permanent magnet synchronous motors. The novelty of the model is that it integrates the polarity-dependent saliency into the traditional machine model and introduces a new machine parameter, the polarity-dependent saliency coefficient, to specify the Hessian matrix of the flux-current function. A measurement method is presented for determination of the elements of the Hessian and the polarity-dependent saliency coefficient. The solution of the model is given for high-frequency sinusoidal pulsating voltage injection. Experimental results show that the proposed extended model accurately predicts the amplitudes and phases of the second harmonics of the motor currents, which are the carriers of the polarity-dependent information. This information enables a current measurement-based polarity detection algorithm using the phase difference between the fundamental and second harmonic of the apparent d-axis current. Both the presented measurement data and the proposed model show that injection in the d-direction is optimal for polarity detection.

Open Access: Yes

DOI: 10.3390/en15031131

Comparing Different Phosphorus Extraction Methods: Effects of Influencing Parameters

Csaba Centeri Renato Kalocsai G. Milics Márton Vona Zsolt Biró Viktoria Vona A. J. Kovács J. Kauser István Mihály Kulmány Gergely Jakab

Publication Name: Sustainability Switzerland

Publication Date: 2022-02-01

Volume: 14

Issue: 4

Page Range: Unknown

Description:

The current study compares the phosphorus (P) analysis methods of ammonium lactate (AL), Mehlich 3 (M3); water extraction (P-WA(P)&P-WA(PO4 )), cobalt hexamine (CoHex) and X-ray fluorescence (XRF) as an estimate of total soil P. The ratio of the P-content/XRF was first calculated and compared with the whole dataset. Based on the comparison of all the data, there were significant differences between the results of P-WA(P) and P-WA(PO4 ) vs. M3 and AL, CoHex vs. M3 and CoHex vs. AL methods (p < 0.001). The second step was the analysis of the influencing factors based on their categories for a more in-depth understanding of their role (CaCO3-content, pH, soil texture and clay content). The results showed that higher CaCO3 content (>1%) resulted in lower correlations (6/10 cases). The extraction methods, the soil, the classification method of the soil properties and the statistical analyses affect the evaluation. The dataset covers a good range of the analysed factors for the evaluation of phosphorus in the majority of Hungarian soil types in arable use. There were two methods that detected the largest amount of P from the total P in the soil: AL and M3.

Open Access: Yes

DOI: 10.3390/su14042158

The Impact of Green Marketing on Consumer Behavior in the Market of Palm Oil Products

Renata Machova Tibor Zsigmond Ferenc Bakó Rebeka Ambrus

Publication Name: Sustainability Switzerland

Publication Date: 2022-02-01

Volume: 14

Issue: 3

Page Range: Unknown

Description:

The aim of the article is to examine the impact of green marketing on consumer behavior in the market for products containing palm oil. The first chapter addresses the theoretical approach—the impact of green marketing on consumer behavior. We considered a questionnaire survey to be the most appropriate method to conduct our research. In order to test our hypotheses, we applied Crosstab and Pearson’s chi-square test. The strength of the relationship between the variables was measured using Cramer’s V. The third chapter presents the research results based on the processed information of 527 obtained datasheets from the respondents. The data were collected from Slovak consumers in the summer of 2021. Hypotheses H1 (There is a significant relationship between the opinion of the consumer regarding purchasing products containing palm oil and the knowledge that the product does contain palm oil.) and H2 (There is a relationship between the consumer willingness to refuse the purchase of certain products if it has negative impact on the environment and the generational group the consumer belongs to.) were approved, however the relationship proved to be weak in both cases. The research makes it clear that the majority of consumers do not spend time reading descriptions on product packaging. It might be helpful for companies to make it clear and visible on the packaging that their product does not contain palm oil, informing the consumer and influencing them with the negative emotional message of the advert. The obtained research results are useful both for the producers and the customers.

Open Access: Yes

DOI: 10.3390/su14031364

Analytical procedures for determination of phenolics active herbal ingredients in fortified functional foods: an overview

E. Lakatos V. Kapcsándi Székelyhidi Rita Beatrix Sik Zsolt Ajtony

Publication Name: European Food Research and Technology

Publication Date: 2022-02-01

Volume: 248

Issue: 2

Page Range: 329-344

Description:

Fortification of foods with phenolic compounds is becoming increasingly popular due to their beneficial physiological effects. The biological activities reported include antioxidant, anticancer, antidiabetic, anti-inflammatory, or neuroprotective effects. However, the analysis of polyphenols in functional food matrices is a difficult task because of the complexity of the matrix. The main challenge is that polyphenols can interact with other food components, such as carbohydrates, proteins, or lipids. The chemical reactions that occur during the baking technologies in the bakery and biscuit industry may also affect the results of measurements. The analysis of polyphenols found in fortified foods can be done by several techniques, such as liquid chromatography (HPLC and UPLC), gas chromatography (GC), or spectrophotometry (TPC, DPPH, FRAP assay etc.). This paper aims to review the available information on analytical methods to fortified foodstuffs while as presenting the advantages and limitations of each technique.

Open Access: Yes

DOI: 10.1007/s00217-021-03908-6