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This study presents an experimental investigation on composite beams (CB) to explore the effectiveness of adding external post-tensioning (EPT) force, as a strengthening technique, on the monotonic flexural performance of composite samples. Two experiments on CB were conducted under three-point loading. High-strength steel strands post-tensioned to 46% of the ultimate strength were used to apply the EPT. Moreover, a finite element (FE) model is developed to present numerical investigations on the monotonic and fatigue behaviors of the CB with and without EPT by considering the slip between the concrete slabs and steel beams as well as the fatigue deterioration in the concrete slabs. A FE parametric study is conducted using the proposed FE model to investigate the effect of steel beam grade, tendon eccentricity, span-to-depth ratio, and fatigue loading. The optimum span-to-depth ratio to obtain the maximum contribution of the EPT force in improving the CB capacities is 9.0. Key words: steel and concrete composite beams, post-tensioning, monotonic, experimental, finite element. Cette etude presente une verification experimentale sur les poutres composites (PC) afin d'explorer l'efficacite de l'ajout d'une force de precontrainte par post-tension externe (PTE), comme technique de consolidation, sur la performance de flexion monotone des echantillons composites. Deux experiences sur des PC ont ete menees sous charge en trois points. Des torons d'acier a haute resistance precontraints par post-tension jusqu'a 46 % de la resistance ultime ont ete utilises pour appliquer la PTE. En outre, un modele d'elements finis (EF) est developpe pour presenter des investigations numeriques sur les comportements monotones et de fatigue de la PC avec et sans PTE en considerant le glissement entre les dalles de beton et les poutres d'acier ainsi que la deterioration due a la fatigue dans les dalles de beton. Une etude parametrique des EF est menee a l'aide du modele EF propose pour etudier l'effet de la nuance des poutres d'acier, de l'excentricite du tendon, du rapport portee-profondeur et de la charge de fatigue. Le rapport portee-profondeur optimal pour obtenir la contribution maximale de la force PTE dans l'amelioration des capacites PC est de 9,0. Mots-cles : poutres composites en acier et en beton, post tension, monotone, experimental, element fini., Introduction Concrete and steel composite beams (CB) are widely used in the construction of bridges as effective structural members. The ductility of steel in tension combined with the hardness and [...]

This article explores the interconnections among the single-valued neutrosophic grill, single-valued neutrosophic primal and their stratification, uncovering their fundamental characteristics and correlated findings. By introducing the notion of a single-valued neutrosophic primal, a broader framework including the fuzzy primal and intuitionistic fuzzy primal is established. Additionally, the concept of a single-valued neutrosophic open local function for a single-valued neutrosophic topological space is presented. We introduce an operator based on a single-valued neutrosophic primal, illustrating that the single-valued neutrosophic primal topology is finer than the single-valued neutrosophic topology. Lastly, the concept of single-valued neutrosophic open compatibility between the single-valued neutrosophic primal and single-valued neutrosophic topologies is introduced, along with the establishment of several equivalent conditions related to this notion. [ABSTRACT FROM AUTHOR]

Due to uncertain photovoltaic (PV) power generation, analyzing the voltage stability of transmission networks with a large PV plant is challenging. The stability of PV output power is a critical factor in establishing PV penetration levels in active transmission networks when assessing loading capabilities. Therefore, this article contributes to enhancing the understanding of how a static synchronous compensator (STATCOM) could be used as part of the power system network. STATCOMs are often used to improve the static and transient voltage, maintain transmission limits, and reduce low-frequency disturbances. With the help of a STATCOM unit, a proper investigation and analysis of dynamic voltage stability in a transmission system are presented. The validity of the study is evaluated by the Saudi Arabia grid code (SAGC). The system being tested is comprised of a 300 MW PV plant in Sakaka, Saudi Arabia, integrated into a 17-bus transmission power network and a STATCOM, which is employed at one of the buses. PSAT software is used to evaluate a number of case studies to determine the transient voltage stability with and without the STATCOM and the PV plant. The simulation findings demonstrate how STATCOM functions to improve the quality of the power system in accordance with the SAGC. In addition, the analysis of voltage stability demonstrates that the power network's resilience to short circuits at the PV system's grid connection point significantly impacts the voltage's dynamic behavior. [ABSTRACT FROM AUTHOR]

This paper gives a mathematical formulation for the transverse resonance of thermoelastic nanobeams that are simply supported and compressed with an initial axial force. The nonlocal elasticity concept is used to analyze the influence of length scale with the dual-phase-lag (DPL) heat transfer theory. The nanobeam is due to a changing thermal load and moves in one direction at a constant speed. The governing motion equation for the nonlocal Euler-Bernoulli (EB) beam hypothesis can also be derived with the help of Hamilton's principle and then solved by means of the Laplace transform technique. The impacts of nonlocal nanoscale and axial velocity on the different responses of the moving beam are investigated. The results reveal that phase delays, as well as the nonlocal parameter and external excitation load, have a substantial impact on the system's behavior. [ABSTRACT FROM AUTHOR]

Unreinforced masonry (URM) is one of the most popular construction materials around the world, but vulnerable during earthquakes. Due to its brittle nature, the URM structures may lead to a possible collapse of the wall of a building during earthquake events causing casualties. In the current research, an attempt is made to enhance the seismic capacity of URM structures by proposing a new innovative composite material that can improve the shear strength and deformation capacity of the URM wall systems. The results revealed that the fiber-reinforced plastic having high tensile and shear stiffness can significantly increase in-plane as well as out-of-plane bending strength of the URM wall. It was recorded that the bending moment of the prism increased up to 549.5% by increasing the bending moment from 490 N*mm to 3183 N*mm per mm deflection of prism upon using glass fibers. Moreover, the ductility ratio amplified up to 5.73 times while the stiffness ratio increased up to 4.16 times with the aid of glass fibers. Since the material used in this research work is low cost, easily available, and no need for any skilled labor, which is economically good. Therefore, the URM walls retrofitted with fiber-reinforced plastic is an economical solution. [ABSTRACT FROM AUTHOR]

The small size and clever design of nanoparticles can result in large surface areas. This gives nanoparticles enhanced properties such as greater sensitivity, strength, surface area, responsiveness, and stability. This research delves into the phenomenon of a nanobeam vibrating under the influence of a time-varying heat flow. The nanobeam is hypothesized to have material properties that vary throughout its thickness according to a unique exponential distribution law based on the volume fractions of metal and ceramic components. The top of the FG nanobeam is made entirely of ceramic, while the bottom is made of metal. To address this issue, we employ a nonlocal modified thermoelasticity theory based on a Moore–Gibson–Thompson (MGT) thermoelastic framework. By combining the Euler–Bernoulli beam idea with nonlocal Eringen's theory, the fundamental equations that govern the proposed model have been constructed based on the extended variation principle. The fractional integral form, utilizing Atangana–Baleanu fractional operators, is also used to formulate the heat transfer equation in the suggested model. The strength of a thermoelastic nanobeam is improved by performing detailed parametric studies to determine the effect of many physical factors, such as the fractional order, the small-scale parameter, the volume fraction indicator, and the periodic frequency of the heat flow. [ABSTRACT FROM AUTHOR]

The fiber-reinforced polymeric (FRP) composite can be joined by adhesive bonding or mechanically fastening the composite element. Carbon fiber-reinforced polymers (CFRP) and glass fiber-reinforced polymers (GFRP) are the most common types of polymers. Mechanically fastened or bolted joints do not need treatments, and the surface temperature and other environmental effects such as humidity do not affect its strength. In this research, the previous research that describes the behavior of the composite bolted joint (CBJ) is presented and summarized including the modes of failure of the CBJ, and the experimental works that explain the bearing failure (BF) of the CBJ. In addition, the effects of bolt clamping force (BCF) and techniques that are used to simulate the progressive failure and damage in composite materials and finite element simulation works are surveyed. [ABSTRACT FROM AUTHOR]

In this study, we have simulated transient and steady state free convection flow and heat transfer inside a square enclosure filled with a copper-water nanofluid of spherical shape nanoparticles following Tiwari-Das model. The cavity containing an insulated rectangular obstacle of height ranging from 0% to 50% of the cavity side-length. The vertical sides of the enclosure are kept at different temperatures, while the flat sides are assumed to be adiabatic as the obstacle. The combined method of lines/penalty-artificial compressibility technique (MOL-PACT) has been applied to solve the dimensional time dependent mathematical model after converting it into a non-dimensional structure. The combined method of lines/penalty-artificial compressibility technique is recently successfully applied to simulate free convection of MHD fluid in square enclosure with a localized heating. The extension of this promising technique for studying heat transfer of nanofluids is one of the objectives of this paper. Another objective of the study is to inspect the impact of several model parameters such as, the obstacle height, nanoparticles volume-fraction, nanoparticles radius and Rayleigh number on streamlines, temperature distribution and Nusselt number as an expression of heat transfer inside the enclosure. The results have been discussed and shown graphically. Comparisons with former results for related cases in the literature are made and reasonably good agreements are observed. [ABSTRACT FROM AUTHOR]

The main objective of this work is to study the homogeneous thermoelastic interactions in an isotropic hollow thin cylinder immersed in an electric–magnetic field using the linear Moore–Gibson–Thompson theory of thermoelasticity, taking into account the generalized Ohm's law. The MGT system of thermoelastic equations for the new model is created by incorporating a relaxation period in the Green–Naghdi type III framework. In addition, the Maxwell equations that investigate the effect of the electromagnetic field are presented. While the outer surface of the hollow cylinder is thermally insulated and free of traction, the interior surface is both free of traction and subject to thermal shock. To convert the problem to the space domain only, the Laplace transform methodology is used to solve the governing equations generated in the transformed domain. The theoretical results are computed dynamically and are graphically displayed for a transversely isotropic material using the Honig and Hirdes approach. A comparison of findings based on different (classical and generalized) thermoelastic theories is provided, followed by a discussion on the impact of the applied electromagnetic field. [ABSTRACT FROM AUTHOR]

Pre-stressed steel-concrete composite beams are widely used in bridges around the world. Loads during the service life of bridges may cause failure in the form of fracture in the studs near the ends of the bridge girders. The effect of stud failure on the residual static capacity and residual fatigue life of composite girders is not well investigated. Therefore, this study presents numerical investigations into the effects of the progressive failure of stud shear connectors on the residual static performance and remaining fatigue life of post-tensioned steel-concrete composite beams. The Finite Element (FE) model was validated using existing experimental work. Moreover, the effects of the progressive failure of stud shear connectors on the steel-concrete interface slippage, shear stress range, and compressive and tensile strains were investigated. The behavior of the composite girders in terms of the estimated fatigue life and residual capacity was inversely affected by the number of fractured studs. The AASHTO theoretical equation conservatively estimated the remaining fatigue life until 15% of the rows were removed and then the FE model predicted fewer remaining fatigue cycles than the theoretical equation. Until 15% of the rows were removed, the strengthened sample had a better response in terms of the stress range, tensile and compressive strains, and residual capacity. After that, both the strengthened and non-strengthened samples exhibited similar responses to the failure of studs. Subsequently, the positive effects of the post-tensioning vanish as the end studs fail. Therefore, designers should pay special attention to the ends of post-tensioned composite beams where the local failure of studs is expected. [ABSTRACT FROM AUTHOR]

The study of the effect of the microstructure is important and is most evident in elastic vibrations of high frequency and short-wave duration. In addition to deformation caused by temperature and acting forces, the theory of micropolar thermoelasticity is applied to investigate the microstructure of materials when the vibration of their atoms or molecules is increased. This paper addresses a two-dimensional problem involving a thermoelastic micro-polar half-space with a traction-free surface and a known conductive temperature at the medium surface. The problem is treated in the framework of the concept of two-temperature thermoelasticity with a higher-order time derivative and phase delays, which takes into consideration the impact of microscopic structures in non-simple materials. The normal mode technique was applied to find the analytical formulas for thermal stresses, displacements, micro-rotation, temperature changes, and coupled stress. The numerical results are graphed, and the effect of the discrepancy indicator and higher-order temporal derivatives is examined. There are also some exceptional cases that are covered. [ABSTRACT FROM AUTHOR]

This article aims to present new terms of single-valued neutrosophic notions in the Sostak sense, known as single-valued neutrosophic regularity spaces. Concepts such asr-single-valued neutrosophic semi £-open,r-single-valued neutrosophic pre-£-open, r-single valued neutrosophic regular-£-open and r-single valued neutrosophic α£-open are defined and their properties are studied as well as the relationship between them. Moreover, we introduce the concept of r-single valued neutrosophic θ£-cluster point and r-single-valued neutrosophic γ £-cluster point, r-θ£- closed, and θ£-closure operators and study some of their properties. Also, we present and investigate the notions of r-single-valued neutrosophic θ£-connectedness and r-single valued neutrosophic δ£-connectedness and investigate relationship with single-valued neutrosophic almost £-regular. We compare all these forms of connectedness and investigate their properties in single-valued neutrosophic semiregular and single-valued neutrosophic almost regular in neutrosophic ideal topological spaces in Sostak sense. The usefulness of these concepts are incorporated to multiple attribute groups of comparison within the connectedness and separateness of θ£ and δ£. [ABSTRACT FROM AUTHOR]

In this paper, we prove the existence of a solution of a fractional hybrid differential equation involving the Riemann-Liouville differential and integral operators by utilizing a new version of Kransoselskii-Dhage type fixed-point theorem obtained in [13]. Moreover, we provide an example to support our result. [ABSTRACT FROM AUTHOR]

In the current paper, particular acheivments of single-valued neutrosophic continuity on a singlevalued neutrosophic topological space (𝔗 ̃, 𝜏̃𝛾̃, 𝜏̃𝜂̃, 𝜏̃𝜇̃) are introduced. Some necessary implications between them are illustrated. The theories of r-single-valued neutrosophic compact, r-single-valued neutrosophic ideal compact, r-single-valued neutrosophic quasi H-closed and r-single-valued neutrosophic compact modulo an single-valued neutrosophic ideal I~ are presented and investigated. [ABSTRACT FROM AUTHOR]

The aim of this paper is to introduce various types of r-single-valued neutrosophic open sets based on the single-valued neutrosophic ideals in Decomposition of Š ostak Sense. Different mappings of single-valued continuity and ideal continuity based on the r-single-valued neutrosophic ideal openness are defined and many implications between them are investigated with counterexamples illustrated. [ABSTRACT FROM AUTHOR]

In this paper, a new class of fuzzy ideal sets, namely the r - (τ i , τ j) - θ -generalized fuzzy ideal closed sets, is introduced for fuzzy bitopological spaces in Šostak sense. This class falls strictly in between the class of r - (τ i , τ j) - θ -fuzzy ideal closed sets and the class of r - (τ i , τ j) -generalized fuzzy ideal closed sets. Furthermore, by using the class of r - (τ i , τ j) - θ -generalized fuzzy ideal closed sets we establish a new fuzzy closure operator which generates fuzzy bitopological spaces in Šostak sense. Finally, the (i , j) strongly- θ -fuzzy ideal continuous, (i , j) - θ -generalized fuzzy ideal continuous and (i , j) - θ -generalized fuzzy ideal irresolute mappings are introduced, and we show the (i , j) - θ -generalized fuzzy ideal continuous properly fuzzy ideal bitopological spaces in Šostak sense (for short, fibtss) in between (j , i) strongly- θ -fuzzy ideal continuous and (i , j) -generalized fuzzy continuous mappings. [ABSTRACT FROM AUTHOR]

The prime orbit theorem and Mertens' theorem are proved for a shift dynamical system of infinite type called the Dyck shift. Different and more direct methods are used in the proof without any complicated theoretical discussion. [ABSTRACT FROM AUTHOR]

The intent of this manuscript is to present new rational symmetric ϖ − ξ -contractions and infer some fixed-points for such contractions in the setting of Θ -metric spaces. Furthermore, some related results such as Suzuki-type rational symmetric contractions, orbitally Υ -complete, and orbitally continuous mappings in Θ -metric spaces are introduced. Ultimately, the theoretical results are shared to study the existence of the solution to a fractional-order differential equation with one boundary stipulation. [ABSTRACT FROM AUTHOR]

The objective of this work is to examine the dynamics of a fractional-order susceptible-infectious-recovered (SIR) model that simulate epidemiological diseases such as childhood diseases. An effective numerical scheme based on Grünwald–Letnikov fractional derivative is suggested to solve the considered model. A stability analysis is performed to qualitatively examine the dynamics of the SIR model. The reliability and robustness of the proposed scheme is demonstrated by comparing obtained results with results obtained from a fourth order Runge–Kutta built-in Maple syntax when considering derivatives of integer order. Graphical illustrations of the numerical results are given. The inaccuracy of some results presented in two studies exist in the literature have been clearly explained. Generalizing of the cases examined in another study, by considering a model with fraction-order derivatives, is another objective of this work as well. [ABSTRACT FROM AUTHOR]

In this work, the main concept of the homotopy perturbation method (HPM) was outlined and convergence theorems of the HPM for solving some classes of nonlinear integral, integro-differential and differential equations were proved. A theorem for estimating the error in the approximate solution was proved as well. The proposed HPM convergence theorems were confirmed and the efficiency of the technique was explored by applying the HPM for solving several classes of nonlinear integral/integro-differential equations. [ABSTRACT FROM AUTHOR]

This paper aims to mark out new terms of single-valued neutrosophic notions in a Šostak sense called single-valued neutrosophic semi-closure spaces. To achieve this, notions such as β £ -closure operators and β £ -interior operators are first defined. More precisely, these proposed contributions involve different terms of single-valued neutrosophic continuous mappings called single-valued neutrosophic (almost β £ , faintly β £ , weakly β £ ) and β £ -continuous. Finally, for the purpose of symmetry, we define the single-valued neutrosophic upper, single-valued neutrosophic lower and single-valued neutrosophic boundary sets of a rough single-valued neutrosophic set α n in a single-valued neutrosophic approximation space (F ˜ , δ) . Based on α n and δ , we also introduce the single-valued neutrosophic approximation interior operator int α n δ and the single-valued neutrosophic approximation closure operator Cl α n δ . [ABSTRACT FROM AUTHOR]

This article aims to mark out new conditions for oscillation of the even-order Emden–Fowler neutral delay differential equations with neutral term β 1 ı Φ α [ ζ r − 1 ı ] ′ + β 3 ı Φ α [ ς ξ ı ] = 0. The obtained results extend, and simplify known conditions in the literature. The results are illustrated with examples. [ABSTRACT FROM AUTHOR]

This paper aims to mark out new concepts of r-single valued neutrosophic sets, called r-single valued neutrosophic £-closed and £-open sets. The definition of £-single valued neutrosophic irresolute mapping is provided and its characteristic properties are discussed. Moreover, the concepts of £-single valued neutrosophic extremally disconnected and £-single valued neutrosophic normal spaces are established. As a result, a useful implication diagram between the r-single valued neutrosophic ideal open sets is obtained. Finally, some kinds of separation axioms, namely r-single valued neutrosophic ideal- R i (r- S V N I R i , for short), where i = { 0 , 1 , 2 , 3 } , and r-single valued neutrosophic ideal- T j (r- S V N I T j , for short), where j = { 1 , 2 , 2 1 2 , 3 , 4 } , are introduced. Some of their characterizations, fundamental properties, and the relations between these notions have been studied. [ABSTRACT FROM AUTHOR]

This paper aims to introduce the notion of r-single-valued neutrosophic connected sets in single-valued neutrosophic topological spaces, which is considered as a generalization of r-connected sets in Šostak's sense and r-connected sets in intuitionistic fuzzy topological spaces. In addition, it introduces the concept of r-single-valued neutrosophic separated and obtains some of its basic properties. It also tries to show that every r-single-valued neutrosophic component in single-valued neutrosophic topological spaces is an r-single-valued neutrosophic component in the stratification of it. Finally, for the purpose of symmetry, it defines the so-called single-valued neutrosophic relations. [ABSTRACT FROM AUTHOR]