Terms Of Redistribution Research Articles

Case Studies about Finite Element Modeling and Wireless Sensing of Three Pennsylvania Bridges.

Three Pennsylvanian bridges were studied using finite element and wireless sensor technology. A detailed finite element model of each bridge was created using a commercial software in order to calculate the strains generated by a load that simulates the presence of a standard truck. Pristine and damage scenarios were simulated, and the computed strains were compared to the experimental strains measured with proprietary wireless sensors during a truck test performed by companies not involved in the study presented in this article. The comparison demonstrated the accuracy of the model and the presence of a few non-critical anomalies in terms of load redistribution. In addition, the comparison proved the reliability of the wireless sensing system installed on the bridges, although some drift was observed. The structural monitoring program for the three bridges was also evaluated by processing more than two years of data streamed to a repository.

Bending moments redistribution in two‐span reinforced concrete beams reinforced with FRP bars based on collected data research

AbstractThis article presents a review of state of the art on nonmetallic reinforcement in terms of bending moment redistribution in double‐span elements. The authors present a summary of existing research programs focused on moment redistribution in FRP (Fiber Reinforced Polymer) reinforced concrete (RC). On this basis authors created a database of concrete elements with all the important construction properties of the elements. Gathered data are presented with quantitative analysis of several variables effecting moment redistribution in published articles. In the following publication authors show a research review which includes an analysis of the influence of variable parameters from the point of view of the database, concerning: degrees of longitudinal reinforcement, ratio between degrees of reinforcement in span and over the support, type of reinforcement (FRP/steel/hybrid), concrete class and transverse reinforcement.

Study of bonding parameters with Al and Au wires on Pd and Ag coatings

The process of electrical connection with gold and aluminium wires to palladium and silver electrodes is studied. Parameters of the wire bonding, such as bond force, ultrasonic power, bond time and temperature of the layers, controlled by heating the substrate are varied to explore the reliability of the bonds in terms of mechanical strength, electrical conductivity and interdiffusion of particles between the electrode and functional material at different bonding conditions. The importance of this study is due to the need of electrical connectivity at the stage of wiring and packaging of gas sensors with a novel organic nanomaterial (carbyne), requiring different types of electrodes – Ohmic or Schottky - according to the measurement principle and sensor architecture. Pd and Ag are identified as the most suitable for Ohmic and Schottky contacts, respectively, because of their favourable energy level alignment at the organic/metal interface. The chosen method for bonds testing is measurement of the pull force causing bond failure. The results show that Pd coating was bondable by Au wire, and Ag coating by Al wire, as well as Au on Pd bonds have 4 times higher strength. It is found that the bonding procedure doesn’t affect negatively on the Au/Pd/carbyne interface in terms of diffusion and redistribution of metal particles, but Al/Ag/carbyne is characterized by poor adhesion and the bonds are peeled-off. The results give new knowledge for the fabrication of advanced gas sensors and for the interaction of the carbyne with different metals, which will serve as a base for further optimization of the manufacturing technology toward their commercialization.

4a,4b-Dihydrophenanthrene → cis-stilbene photoconversion: TD-DFT/DFT study.

DHP → CS photoconversion was analyzed in terms of electron density redistribution for the first time. The following explanation for the non-recovery of the C4a-C4b bond upon CS relaxation is proposed: during this process, the Coulomb repulsion energy between these pairs of atoms increases by almost one and a half times, and their bonding by an electron at LUMO is insufficient to recover the C4a-C4b bond. According to calculations, upon CS relaxation, the linker connecting the benzene rings undergoes significant structural changes. In this case, the distance between the C4a and C4b atoms increases from 3.00Å to 3.28Å. Calculations showed that the C4a-C4b vibration of the DHP bond has a very low intensity. Therefore, thermal motion does not contribute to the rupture of this bond. All calculations were performed using the Gaussian16 software package at the B3LYP/6-311 + + G(d,p)/IEFPCM theory level. B3LYP was the only hybrid functional supported by Gaussian16, which ensured the cleavage of the C4a-C4b bond of DHP while optimizing its S1 excited state. A quantitative description of the redistribution of electron density in the studied conformers was carried out using the analysis of the NPA of atomic charges. Cyclohexane was used as an implicitly specified non-polar solvent. Visualization of molecular orbitals, and electron densities, as well as plotting of calculated IR spectra, were performed using the Gaussview6 software package.

Enhancing turbulence modeling: Machine learning for pressure-strain correlation and uncertainty quantification in the Reynolds stress model

This research study delves into the realm of enhancing the Reynolds stress model through the remarkable capabilities of machine learning. Focusing on two key aspects, we investigate the modeling of fluctuating pressure-rate-of-strain tensor and uncertainty quantification in turbulent fluid flows. In the first part of our investigation, a neural network is employed to predict the pressure-strain correlation term for the frictional Reynolds number, even in cases where it was not trained. Through the use of high-fidelity datasets, we surpass the limitations of traditional numerical methods, achieving more accurate results with reduced computational costs. Going beyond conventional analysis, we explore the isotropic and anisotropic components of the pressure-strain correlation term. Intriguingly, our findings unveil the significant influence of production and redistribution terms on the anisotropic component by 50% and viscous dissipation impacts the isotropic part by 65% in wall-bounded turbulent flows. The second part introduces a novel approach for uncertainty quantification in the Reynolds stress model. Leveraging a binary classification model, we identify error-prone points within the simulation domain with an impressive accuracy of up to 95%. This critical step paves the way for a deeper understanding of uncertainties in turbulent flows for more reliable predictions. By harnessing the power of machine learning, our study provides two compelling ways to enhance the Reynolds stress model, contributing to a more efficient and dependable prediction of turbulent fluid dynamics.

QTAIM based descriptors for the classification of acrylates

Acrylates are used in cosmetics, orthopedics, paints, coatings, adhesives, textiles, and biomedical applications such as contact lenses and bone cements. However, some acrylates are mutagenic and the aim of this article is to explain the mutagenicity in terms of the atomic population redistribution in the molecule using two new descriptors which are based on atomic populations framed in the quantum theory of atoms in molecules. They describe the electron-withdrawing effect of a group of atoms in a molecule. The descriptors consider substituents of prop-2-enoates, the number of the acrolein units and the electrophilicity. The cluster analysis using these descriptors allows to classify acrylates in terms of the number of acrolein backbones and the type of the substituent group. Five main groups can be distinguished: monoacrylates with monomethacrylates, diacrylates with dimethacrylates, triacrylates, trimethacrylate and monoacrylates with electron-rich substituents. The substituents of mutagenic acrylates are electron withdrawing. This makes the acrolein backbone β-carbon more electrophilic and the molecule more reactive.

Tandem reactions on phase separated MnO2 and C to enhance formaldehyde conversion to hydrogen

Hydrogen production from formaldehyde aqueous solution at room temperature shows a unique advantage regarding the bi-functional reaction route. MnO2 was reported to be an active catalytic material for this process, especially after coating with carbon composite for improved active site distribution. Here, we unravel that the conversion of formaldehyde can be treated as two tandem half-reactions: the oxidative dehydrogenation (ODH) of formaldehyde and the hydrogen evolution reaction (HER). β-MnO2 in a physical mixture with carbon (i.e., XC-72R, graphene) enhances both formaldehyde conversion (from 13% to 19.5%) and hydrogen productivity (from 22.35 μmol mg−1 h−1 to 33.86 μmol mg−1 h−1) by a synergistic effect of the phase separation catalyst in terms of electron redistribution and transport over the active sites. The catalyst examination supported by DFT calculation shows relatively low activation energy and band gap of β-MnO2 + C with a density of states spanning the Fermi level. The discovery of this novel synergistic catalytic effect: a phase separation catalyst with cooperative enhancement, provides new insight into the area of tandem catalysis.

Problematika péče o děti mladší tří let v České republice

The article discusses theoretical and practical issues of child care for under three-yearold children. The article looks at the issue from three perspectives which affect injustices. Firstly, in terms of every day struggles for recognition, which should have been understood as full-fledged activity with appropriate social status. Secondly, in terms of redistribution of public resources and financial reward for caring for children under the age of three. Thirdly, in terms of political injustice, which will inevitably limit people’s capacity to engage in all kinds of civic and political activity. Following the Nancy Fraser’s thinking, article shows that is it necessary to understand recognition and redistribution unconditionally but in the unified horizon. The structures of injustice for children under the age of three are connected and only one of these approaches is not able to solve injustice. The article brings, with the helping hands of critical methods, new perspectives, and approaches to care issues that target breaking actions of national Czech Republic norms and remove rigid social and institutional systems and policies that structure inequality on this field.

Effect of in-source beam shaping and laser beam oscillation on the electromechanical properties of Ni-plated steel joints for e-vehicle battery manufacturing

Laser welding is a key enabling technology that transitions toward electric mobility, producing joints with elevated electrical and mechanical properties. In the production of battery packs, cells to busbar connections are challenging due to strict tolerances and zero-fault policy. Hence, it is of great interest to investigate how beam shaping techniques may be exploited to enhance the electromechanical properties as well as to improve material processability. Industrial laser systems often provide the possibility to oscillate dynamically the beam or redistribute the power in multicore fibers. Although contemporary equipment enables elevated flexibility in terms of power redistribution, further studies are required to indicate the most adequate solution for the production of high performance batteries. Within the present investigation, both in-source beam shaping and beam oscillation techniques have been exploited to perform 0.2–0.2 mm Ni-plated steel welds in lap joint configuration, representative of typical cell to busbar connections. An experimental campaign allowed us to define process feasibility conditions where partial penetration welds could be achieved by means of in-source beam shaping. Hence, beam oscillation was explored to perform the connections. In the subset of feasible conditions, the mechanical strength was determined via tensile tests alongside electrical resistance measurements. Linear welds with a Gaussian beam profile enabled joints with the highest productivity at constant electromechanical properties. Spatter formation due to keyhole instabilities could be avoided by redistributing the emission power via multicore fibers, while dynamic oscillation did not provide significant benefits.

Attraction-Induced superlubricity and its detection

A nanoscale friction test using an atomic force microscope (AFM) is modelled as a diatomic tip in sliding contact with a 2D monolayer supported by a metal substrate. This test is simulated by ab initio DFT calculations. The simulation results show that, when a silver tip slides on a honeycomb borophene (HB) monolayer supported by a titanium substrate, the friction force varies nonlinearly with the prescribed height of the tip or, equivalently, the corresponding normal force exerted by the tip on the HB monolayer. In particular, the friction force turns out to be almost null when the height of the tip sufficiently approaches a critical height of the prescribed height, which corresponds to a critical normal attraction force. This nanoscale friction-free sliding phenomenon is thus qualified as attraction-induced superlubricity (AISL). Further, the origin of AISL is discussed and analyzed in terms of electron redistributions. Finally, the feasibility of AISL detection is argued by analyzing the potential energy surface (PES), the adsorption strength of the tip on HB surface and the binding strength of HB to its substrate.

Preliminary thermographic and statistical analysis of surface topography non-uniformities produced by laser remelting on metallic surfaces

Surface polishing by laser remelting (SP-LRM aka laser polishing) is a material finishing process that uses the thermal energy of a laser beam tracked across a surface remelting a thin surface layer at the laser incidence. This causes formation of thermodynamic molten material flows within a melt pool leading to the redistribution of the initial surface topography and bulk material with hills flowing into valleys. The effectiveness of this process is highly dependent on a complex combination of the laser-motion-material parameters (e.g., power, speed, focus offset, etc.) and their formation of thermodynamic flows in the laser-material interaction zone. In an ideal case, the chosen process parameter combination forms a stable thermodynamic equilibrium between applied laser energy and convection, conduction and radiation being the triplet of thermal energy components. It is assumed that this stable thermodynamics of laser-material interaction leads to the formation of uniform (in terms of material redistribution) laser remelted tracks. Thermodynamic instabilities on the contrary may cause sudden variations and non-uniformities in the surface topography, such as bulges, cavities, and wide/narrow stripes, negatively affecting the smoothening effect of surface polishing. This study demonstrates the formation of uniform laser tracks from a stable LRM process and non-uniform laser tracks from a non-stable LRM process through the use of statistical analysis of the surface topography measured off-line by white-light interferometry and in-situ thermographic imaging. Through a combination of these techniques, multiple examples of regions containing different types of these undesired surface topography non-uniformities are identified. One of the goals of this study was to find an interdependence between laser-processed surface topography and thermographic response. For this purpose, information data have been synchronized in time and space domain. In detail, stable and non-stable LRM process states, typical thermodynamic instabilities, initial surface defects, and especially the beginning and ending of LRM tracks are analyzed. The results from this preliminary study lay a scientific and engineering basis to better understand the thermodynamics of the LRM process and identify statistical metrics capable of recognizing thermodynamic imbalance for future development of online LRM process monitoring, control, and optimization.

A transnational exchange mechanism among Moldovan migrants in the Parisian region: exploring the “post office of Moldova”

This article delves into the phenomenon of material goods circulation in the context of international migration, specifically looking at the exchange of parcels between Moldovan immigrants in the Paris region, France, and their kin, friends, and acquaintances in Moldova. The analysis uses field data collected during an ethnographic study conducted in 2017 within the Moldovan immigrant community in Paris. It moves beyond the limitations of push-pull theories that focus solely on one-way material circulation from immigrants to their home country families or only on the economic implications of remittances. Adopting a diverse methodological and epistemological stance, the author's inductive approach highlights the heuristic value of the field data. This data suggests that the parcel exchange between Moldovan immigrants and their compatriots carries significant social and symbolic meaning for all actors involved in this process. Over time, this exchange has evolved into a social institution, creating an ongoing link between the host country and the country of origin. The author scrutinizes the material and symbolic processes involved in the parcel transfer mechanism, whimsically referred to by the migrants as "Post Office of Moldova", the name of the national postal service in Moldova. The article explores both the commercial and non-commercial dynamics that shape this mechanism's operations and its integrative impact on the Moldovan immigrant community in the Paris region. The motivations that drive these material flows associated with migration are portrayed in terms of reciprocity, redistribution, and altruism, thereby emphasizing the reciprocal nature of these exchanges.

The Study of an Energy Management Strategy within a Microgrid with Photovoltaic Production of the <<PROPRE.MA>> Project in the City of Tangier and Integrating V2G Technology

The energy stored in an electric vehicle’s (EV’s) battery would be drawn and distributed to the electrical grid to better drive energy consumption within a microgrid that includes a renewable generator(s) managed by a specific energy management strategy. This concept, known as vehicle-to-grid technology (V2G), makes the energy stored in the electric vehicle’s battery more beneficial by discharging it to the public grid during periods of high demand. In this study, we will consider a vehicle system connected to a microgrid, which includes a photovoltaic generator reported from the <<PROPRE.MA>> project in the city of Tangier, and will elaborate on a strategy of the car connected to the V2G (vehicle to grid) network. This study proposes an optimal energy management strategy within the micro grid to charge the battery of a single electric vehicle during off-peak hours when energy costs are low, and to discharge them for driving purposes during peak hours when the energy cost is high. This is explored through a case study of two scenarios in the form of two different driving profiles of electric vehicles. The goal is to understand the behavior of the system in terms of energy redistribution from the V2G and from G2V (grid to the vehicle), and the contribution of the photovoltaic array reported by the <<PROPRE.MA>> photovoltaic generator in the city of Tangier. This study is conducted in a simplified standard Matlab microgrid with the necessary adaptation for the integration of this project generator into the grid, along with a judicious choice of an EV to ensure more explicit battery behavior in relation to our grid parameters. The simulation covers a single day (24 h). This strategy will manage the solar power, the load power, the state of charge of the EV battery, the time of day, and the driving scenario. Using two driving profiles, we will show the performance of the proposed energy management strategy. On the one hand, the V2G technology depends on the driving profile of the EV user is demonstrated. On the other hand, the 100%, 4.65% and 3.32% contributions of the 6 kW photovoltaic generator of the project <<PROPRE.MA>> in the city of Tangier are demonstrated. This contribution covers the load demand for charging of the battery of the electric vehicle that does not have the possibility to charge at work, as well as charging of the battery of the electric vehicle that can be charged at work.

The quest for justice in education: capital and funds of knowledge

This paper explores the funds of knowledge approach to pedagogy and educational research from a social justice perspective. In response to the suggestion made by some authors that the approach should be integrated with a capital perspective, we argue that this would work only if the concept of capital is understood in a certain way. Also, and more generally, we try to show that redistribution in education should not be thought of in terms of capital redistribution, but in terms of counteracting structural barriers to participatory parity which result in status differences among citizens. Finally, we suggest three concrete ways this can be achieved through pedagogies based on funds of knowledge.

Optimal power distribution with mitigation of DC voltage fluctuations using artificial intelligent droop control scheme for MTDC grid

Optimal power share contribution with minimum DC voltage deviations is highly recommended in voltage source converter multi-terminal DC (VSC-MTDC). Hence, in this study, an artificial neural network based intelligent adaptive droop control proposes to enhance MTDC closed-loop system dynamics in terms of optimal power share and small redistribution of terminal DC voltages with negligible oscillations even in the presence of AC grid load demand change, admittance matrix uncertainty, outage of terminals and integration of wind farms. This is achieved via three-layer neural network and its weights are adaptively updated using error-back propagation algorithm. The asymptotic convergence of proposed control is derived using the Lyapunov’s stability theorem. Thus, the proposed intelligent adaptive droop control strategy not only guarantees to improve power share contribution with minimum voltage but also improved power quality and service continuity of MTDC grid. The robustness of proposed intelligent adaptive droop control is demonstrated on five terminal multi-terminal DC grid via MATLAB®.

Numerical Assessment on Continuous Reinforced Normal-Strength Concrete and High-Strength Concrete Beams

High-strength concrete (HSC) has been broadly applied to various civil structures for its advantages including high compressive strength and excellent durability and creep resistance. However, the brittleness of HSC raises concern about its use in practice. So far study on continuous reinforced HSC beams is limited. This work investigates the structural response of reinforced HSC continuous beams, and the results are compared with those of the counterparts made of normal-strength concrete (NSC). By applying a finite element method verified by experimental data, a comprehensive assessment is performed on two-span reinforced NSC and HSC (compressive strengths of 30, 60 and 90 MPa) continuous beams. A wide range of flexural reinforcement ratios are used to cover both under-reinforced and over-reinforced beams. The results show that reinforced HSC beams exhibit better flexural performance in terms of ultimate load, deformation, flexural ductility and moment redistribution, when compared to reinforced NSC beams. Formulae relating flexural ductility and moment redistribution with either neutral axis depth or tensile steel strain are suggested.

On the concentration fluctuation moments of gas species in turbulent combustion

For exploring the influences of chemical reaction on the turbulent fluctuations of gas species concentrations, the reaction source terms in the transport equations for the concentration fluctuation moments are analyzed. It is found that the reaction source terms taken from the equations for the fuel-oxygen, fuel, and oxygen concentration fluctuation moments have a fixed relationship among them. The reaction source terms are not pure production or dissipation terms and they play a redistribution role in these equations. The algebraic concentration moment (ACM)-probability density function (PDF) turbulent combustion model is evaluated. It indicates that the reaction source terms in the modeled transport equations and the resultant explicit algebraic expressions for the concentration fluctuation moments all satisfy the fixed relationship. The reaction source terms serve as the redistribution terms in the explicit expressions for the concentration fluctuation moments.

Projected Atlantic overturning slow-down is to be compensated by a strengthened South Atlantic subtropical gyre

The upper limb of the Atlantic meridional overturning circulation brings shallow interocean contributions to replenish the North Atlantic export of deepwaters. It is primarily formed in the southern South Atlantic where the converging entrainment of Pacific and Indian Ocean waters meet and incorporate into the South Atlantic subtropical gyre. Here, we use Community Earth System Model 1 Large Ensemble simulation results along 1920–2100 to investigate the response of the Atlantic meridional overturning circulation upper limb and the South Atlantic subtropical gyre to future human-induced climate warming under business-as-usual greenhouse gas emissions. In terms of flow redistribution, we find that the Atlantic meridional overturning circulation upper limb weakens not because less waters are being imported from the Pacific and Indian basins — but because waters are being mostly directed to recirculate in the southwestern portion of a distorted South Atlantic subtropical gyre, turning back southward after reaching the South Atlantic western boundary.

Cardiomyocyte sarcolemma modelling and lipid-protein interactions.

The cardiomyocyte sarcolemma is a crucial cellular organelle in heart function. The vital components of the sarcolemma are membrane proteins that generate and control the cardiac action potential, responsible for cardiomyocyte contractibility and heart rhythm. Their malfunction can be caused by congenital mutations and side effects of antiarrhythmic therapies and can lead to life-threatening conditions related to heart failure. Other main components are represented by several lipid types, which not only provide the matrix for membrane proteins but also play active roles in regulating protein function. Shifts in membrane physiology through changes in the lipidomic profile or lipid-protein interactions can also cause cardiac disorders. Our goal is to characterize specific lipid-protein interactions in the sarcolemma by studying lipid redistribution around proteins and identifying lipid binding sites that can potentially regulate protein function. We combined lipidomic, cryo-electron microscopy and X-ray crystallography studies to build computational models of the cardiomyocyte sarcolemma. The membrane models consist of 16 lipid species, which differ in headgroup type, levels of acyl tail unsaturation and length. We embedded a selected membrane protein (cardiac ion channel, transporter or receptor) in a lipid bilayer and performed molecular dynamics simulations with the Martini coarse-grained models. We simulated each system with a corresponding membrane protein for 120 μs and analyzed lipid-protein interactions in terms of lipid redistribution around the proteins via computing lipid depletion-enrichment index, lipid density, and predicting lipid binding sites.Our results reproduce experimental findings of the interactions between lipids and the Kir2.2 potassium channel. We propose potential lipid binding sites for other proteins, highlighting similarities and differences in lipid redistribution and interaction with the cardiomyocyte proteins. Such findings unveil new possible lipid-protein interactions in the cardiomyocyte sarcolemma and provide an understanding of their relevance in heart function.

Segregation of rare earth elements in the melting process for injection casting of U–Zr metallic fuels

We investigated the segregation behavior of rare earth elements (RE = La, Ce, Pr, and Nd) in the injection casting process of U–Zr metallic fuel using the characterization methods such as density measurement, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and inductively coupled plasma−atomic emission spectroscopy. Injection casting of the metallic fuels with nominal compositions of U–10Zr−xRE (in wt%, x = 5, 7, and 10) resulted in the fuel slugs exhibiting similar compositions regardless of the RE content charged in the melting crucible. The microstructure observations revealed that RE-segregated layer occupied the upper region of the melt-residue in case of injection casting of U–10Zr−7RE and U–10Zr−10RE while the melt-residue of U–10Zr−5RE was relatively homogenous in terms of RE distribution. The segregation was caused by the immiscibility of RE in U–Zr alloys. When the RE content was higher than 5 wt%, the thickness of the segregation layer increased with the amount of the charged RE. RE inclusions migrated toward the upper region of the molten alloy owing to the different densities and specific gravities as compared to that of the U–Zr alloy, which led to the non-uniformity in the composition of the melt-residue after injection casting of U–10Zr−7RE and U–10Zr−10RE. The migration behavior of RE during melting was suggested to be induced by the fractional crystallization owing to the immiscibility and the difference in solidification temperature.