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Elasto-Plastic Analysis of Two-Way Reinforced Concrete Slabs Strengthened with Carbon Fiber Reinforced Polymer Laminates

Zahraa Saleem Sharhan Majid Movahedi Rad

Publication Name: Computation

Publication Date: 2024-05-01

Volume: 12

Issue: 5

Page Range: Unknown

Description:

This study explores a technique for enhancing the punching strength of reinforced concrete (RC) flat slabs, namely carbon fiber reinforced polymer (CFRP). Four large-scale RC flat slabs were fabricated, to assess the efficacy of this strengthening method. One slab served as a reference and the three other specimens were strengthened with CFRP, as a method of external strengthening. These slabs, featuring identical overall dimensions and flexural steel reinforcement, underwent testing until failure, under the influence of concentrated patch loads. A concrete plastic damage constitutive model (CDP) was developed and employed to examine the strength of two-way RC slabs. Additionally, to enhance the strength of existing RC slabs, carbon fiber reinforced polymer (CFRP) strips are affixed to the tension surface of the sections. The research begins with the calibration of a numerical model, based on data from laboratory tests. The objective of this study is to constrain the plastic behavior of two-way RC slabs reinforced with CFRP, with a focus on establishing an optimal elasto-plastic analysis, aimed at controlling concrete damage plasticity using CFRP, and employing a plastic limit load multiplier. Subsequently, a series of numerical simulations, incorporating different variables, are conducted to investigate shear behavior. The numerical results indicate that an increase in the strengthening ratio has a significant impact on shear strength. Finite element simulations are carried out using Abaqus CAE®/2018.

Open Access: Yes

DOI: 10.3390/computation12050093

Sustainability accounting for greenhouse gas emissions measurement using the GREET LCA model: practical review of automotive ESG reporting

Árpád Tóth Alex Suta Péter Molnár

Publication Name: Clean Technologies and Environmental Policy

Publication Date: 2024-05-01

Volume: 26

Issue: 5

Page Range: 1631-1642

Description:

The production and personal use of passenger vehicles contribute significantly to greenhouse gas (GHG) emissions, making personal transport a major contributor. In response to increasing pressure from regulators and consumers to lower emissions, original equipment manufacturers (OEMs) have introduced alternative powertrains, such as battery electric vehicles (BEVs). To assess the economic and environmental feasibility of BEVs, OEMs conduct various life cycle assessment (LCA) approaches as part of their internal management practices. However, the public presentation of their results is often ambiguous and of unverifiable quality. This study conducts a review of sustainability impact reporting using the GREET model, which is based on the total vehicle life cycle. The paper provides a summary of the input data requirements for validating emissions from both the fuel and vehicle cycles as part of the proposed model. The availability of the model components was tested against actual public corporate environmental, social and governance reporting disclosures of the largest global automotive OEMs, indicating a deficit in the public presentation of essential sustainability information. The implications of the research suggest that LCA models could benefit sustainability accounting by incorporating proper tagging during accounting practices and taking advantage of digital accounting and reporting practices such as the extensible business reporting language (XBRL). By further developing the model, sustainability reporting can benefit from its structure and workflow, thus ensuring improved information validity for stakeholders. Graphical abstract: (Figure presented.)

Open Access: Yes

DOI: 10.1007/s10098-023-02588-y

Evaluation of the physical, antioxidant, and organoleptic properties of biscuits fortified with edible flower powders

E. Lakatos Székelyhidi Rita Beatrix Sik Laura Hanna Gál Zsolt Ajtony

Publication Name: Food Science and Nutrition

Publication Date: 2024-05-01

Volume: 12

Issue: 5

Page Range: 3265-3272

Description:

Foods enriched with plants have gradually become an area of increasing research interest because plant ingredients may offer several positive effects on human health and the body. The aim of our study was to develop biscuits fortified with three different types of edible flowers (marigold, lavender, and rose) and examine their physical and antioxidant characteristics, as well as consumer acceptability. The antioxidant properties and characterization of biscuits highlighted that edible flowers may cause increased total polyphenol and total flavonoid yields, as well as DPPH radical scavenging activities. Concerning biscuits fortified with rose petals, the total monomer anthocyanin content was also raised. In addition, the results showed that the antioxidant properties of biscuits increased with increasing concentration (from 2.5% to 5.0%) of edible flowers. Despite this, the consumer acceptability results clearly showed that the addition of marigold and lavender at a concentration of 5.0% caused significantly decreased overall acceptance. We found that the fortification step may increase the spread ratio, which is an important quality attribute of biscuits. We found slight variations in the diameter, thickness, and baking loss parameters of fortified biscuits compared to the control. All in all, the best results were obtained when the biscuits were fortified with rose petals at a concentration of 5%.

Open Access: Yes

DOI: 10.1002/fsn3.3993

Self-Diagnostic Opportunities for Battery Systems in Electric and Hybrid Vehicles

I. Lakatos Szabolcs Kocsis Szurke Péter Ori Gergő Sütheö

Publication Name: Machines

Publication Date: 2024-05-01

Volume: 12

Issue: 5

Page Range: Unknown

Description:

The number of battery systems is also growing significantly along with the rise in electric and hybrid car sales. Different vehicles use different types and numbers of batteries. Furthermore, the layout and operation of the control and protection electronics units may also differ. The research aims to develop an approach that can autonomously detect and localize the weakest cells. The method was validated by testing the battery systems of three different VW e-Golf electric vehicles. A wide-range discharge test was performed to examine the condition assessment and select the appropriate state of charge (SoC) for all three vehicles. On the one hand, the analysis investigated the cell voltage deviations from the average; the tests cover deviations of 0 mV, 12 mV, 60 mV, 120 mV, and 240 mV. On the other hand, the mean value calculation was used to filter out possible erroneous values. Another important aspect was examining the relationship between the state of charges (SoC) and the deviations. Therefore, the 10% step changes were tested to see which SoC level exhibited more significant voltage deviations. Based on the results, it was observed that there are differences between the cases, and the critical range is not necessarily at the lowest SoC level. Furthermore, the load rate (current) and time of its occurrence play an important role in the search for a faulty cell. An additional advantage of this approach is that the process currently being tested on the VW e-Golf can be relatively simply transferred to other types of vehicles. It can also be a very useful addition for autonomous vehicles, as it can self-test the cells in the system at low power consumption.

Open Access: Yes

DOI: 10.3390/machines12050324

Frequency- and Temperature-Dependent Uncertainties in Hysteresis Measurements of a 3D-Printed FeSi wt6.5% Material

Tamas Orosz B. Kocsis

Publication Name: Sensors

Publication Date: 2024-05-01

Volume: 24

Issue: 9

Page Range: Unknown

Description:

Additive manufacturing of soft magnetic materials is a promising technology for creating topologically optimized electrical machines. High-performance electrical machines can be made from high-silicon-content FeSi alloys. Fe-6.5wt%Si material has exceptional magnetic properties; however, manufacturing this steel with the classical cold rolling methodology is not possible due to the brittleness of this material. Laser powder bed fusion technology (L-PBF) offers a solution to this problem. Finding the optimal printing parameters is a challenging task. Nevertheless, it is crucial to resolve the brittleness of the created materials so they can be used in commercial applications. The temperature dependence of magnetic hysteresis properties of Fe-6.5wt%Si materials is presented in this paper. The magnetic hysteresis properties were examined from 20 °C to 120 °C. The hysteresis measurements were made by a precision current generator–based hysteresis measurement tool, which uses fast Fourier transformation–based filtering techniques to increase the accuracy of the measurements. The details of the applied scalar hysteresis sensor and the measurement uncertainties were discussed first in the paper; then, three characteristic points of the static hysteresis curve of the ten L-PBF-manufactured identical toroidal cores were investigated and compared at different temperatures. These measurements show that, despite the volumetric ratio of the porosities being below 0.5%, the mean crack length in the samples is not significant for the examined samples. These small defects can cause a significant 5% decrement in some characteristic values of the examined hysteresis curve.

Open Access: Yes

DOI: 10.3390/s24092738

Linking gold prices, fossil fuel costs and energy consumption to assess progress towards sustainable development goals in newly industrialized countries

Laszlo Vasa Yuriy Bilan Syed Ali Raza Muhammad Farhan Bashir Muhammad Adnan Bashir

Publication Name: Geoscience Frontiers

Publication Date: 2024-05-01

Volume: 15

Issue: 3

Page Range: Unknown

Description:

The continuous rise in global environmental challenges has led to urgency toward establishing a secure framework to achieve sustainable development goals. This study establishes a novel theoretical framework to analyze the role of energy prices, energy consumption, gold prices and economic growth on environmental degradation in newly industrialized economies. To realize sustainable development goals and foster environmental defence, this study utilizes CS-ARDL as the main econometric approach to investigate the asymmetric association between environmental degradation and relevant factors. We also use AMG, CS-DL, Driscoll-Kray and FGLS to enhance the robustness of our findings. Our econometric approach reveals that energy resource prices and renewable energy consumption reduce environmental degradation, while gold prices and fossil energy consumption elevate environmental pollutants. We also confirm the existence of the EKC hypothesis. The findings of our extensive analysis paved the way for a well-designed environmental policy for NIC economies should focus on renewable energy consumption, green investments, and structural changes.

Open Access: Yes

DOI: 10.1016/j.gsf.2023.101755

Flow Simulation in an Alga Photobioreactor Tested Under Laboratory Conditions

Roland Jančo Tibor Tolner Imre Neményi Miklos

Publication Name: Strojnicky Casopis Journal of Mechanical Engineering

Publication Date: 2024-05-01

Volume: 74

Issue: 1

Page Range: 35-44

Description:

For the purpose of efficient algae cultivation, the Photo Bio-Reactor (PBR) must be designed according to the needs of the algae to be cultivated. We performed our experiment with a loop reactor with a total volume of 14 liters. Among other things, the mixing of the gas and liquid phases, the value and change of the light intensity reaching the algae, and the degree of algae deposition on the walls of the equipment depend on the flow caused by the bubble column in the equipment. Using the ANSYS FLUENT simulation environment, we optimized the efficiency of the gas intake that determines the flow.

Open Access: Yes

DOI: 10.2478/scjme-2024-0004

Constructing and sampling partite, 3-uniform hypergraphs with given degree sequence

András Hubai Tamás Róbert Mezei Ferenc Béres András Benczúr István Miklós

Publication Name: Plos One

Publication Date: 2024-05-01

Volume: 19

Issue: 5 May

Page Range: Unknown

Description:

Partite, 3-uniform hypergraphs are 3-uniform hypergraphs in which each hyperedge contains exactly one point from each of the 3 disjoint vertex classes. We consider the degree sequence problem of partite, 3-uniform hypergraphs, that is, to decide if such a hypergraph with prescribed degree sequences exists. We prove that this decision problem is NP-complete in general, and give a polynomial running time algorithm for third almost-regular degree sequences, that is, when each degree in one of the vertex classes is k or k − 1 for some fixed k, and there is no restriction for the other two vertex classes. We also consider the sampling problem, that is, to uniformly sample partite, 3-uniform hypergraphs with prescribed degree sequences. We propose a Parallel Tempering method, where the hypothetical energy of the hypergraphs measures the deviation from the prescribed degree sequence. The method has been implemented and tested on synthetic and real data. It can also be applied for χ2 testing of contingency tables. We have shown that this hypergraph-based χ2 test is more sensitive than the standard χ2 test. The extra sensitivity is especially advantageous on small data sets, where the proposed Parallel Tempering method shows promising performance.

Open Access: Yes

DOI: 10.1371/journal.pone.0303155

Artificial intelligence, disruption of financial markets and natural resources economy in the digital era

Gagan Deep Sharma Seyfettin Erdoğan Ayfer Gedikli Shawkat Hammoudeh

Publication Name: Resources Policy

Publication Date: 2024-05-01

Volume: 92

Issue: Unknown

Page Range: Unknown

Description:

No description provided

Open Access: Yes

DOI: 10.1016/j.resourpol.2024.104953