ABSTRACT One of the aspects that affect structure stability is the soil–structure interaction. A good example of this interaction can be witnessed in footings, in which the properties of the soil surrounding the structural parts and the structural parts themselves affect the engineering behavior of the interaction between concrete footings and the soil. Contact stress distribution represents such interaction. However, contact stress distribution beneath concrete footings does not solely rely on the soil type and behavior of footing in working limit state, but also on the variation in the concrete footings stiffness after cracking. The main purpose of this research is to investigate the effect of the reduction in the concrete footing stiffness due to cracking on the contact stress distribution beneath concentric isolated footings resting on cohesive soil. In this respect, numerical simulation and validation was carried out using a non-linear finite element program ‘Abaqus’. A parametric study was conducted to extend this study by including soil cohesion, internal friction angle, rebars yield strength, and foundation depth as investigated parameters. The concrete foundation behavior and failure mode were analyzed. The findings of this research indicate that the different variations of cracks in reinforced concrete showed different shapes of contact stress distribution.

Rough set theory is commonly used to handle uncertainty in various applications. In order to broaden its application scope, the classical rough set model based on equivalence relations, it has been extended to include an additional partial order relation. This partial order relation represents an m-nano flou set, as defined in Section 5, between rough sets and is particularly useful in determining the levels of impact that key factors have on heart failure. The primary objective of the current research is to introduce a novel approximation method based on equivalence relations and partial order relations (ordered approximation spaces), which extends Pawlak's method and investigates related results. The paper establishes the equivalence between our approach and Pawlak's approach under the condition that we have an equivalence relation and a partial order relation that satisfies the criteria required for it to be considered an equality relation. The second objective is to extend the concept of nano topology to include nano ordered topology, which involves nano increasing or decreasing topological spaces. The research indicates that incorporating nano increasing or decreasing topological spaces results in enhanced data analysis accuracy when compared to solely utilizing nano topological spaces. This observation aligns with the discussions in the referenced work by Jayalakshmi. The findings of this research have the potential to significantly impact medical research related to heart failure. Improved methods for handling uncertainty and quantifying the influence of various factors can lead to more accurate and reliable predictions and diagnoses. Ultimately, this work aims to contribute to advancements in heart failure treatment and prevention. By bridging the gap between traditional rough set theory and the nuanced intricacies of heart failure analysis, our research strives to advance our comprehension of this critical medical condition and, in turn, support progress in heart failure treatment and prevention.

Double-junction solar devices featuring wide-bandgap and narrow-bandgap sub-cells are capable of boosting performance and efficiency compared to single-junction photovoltaic (PV) technologies. To achieve the best performance of a double-junction device, careful selection and optimization of each sub-cell is crucial. This work presents the investigation of an all-thin-film two-terminal (2T) monolithic homojunction perovskite (PVK)/c-Si tandem cell using Silvaco TCAD simulation. The front sub-cell utilizes homojunction PVK that has a bandgap of 1.72 eV, whereas the rear sub-cell uses thin c-Si with a bandgap of 1.12 eV. Both cells are connected via a p++/n++ silicon tunnel diode. Experimental calibration of the heterojunction PVK and c-Si cells yields power conversion efficiencies (PCE) of 18.106% and 17.416%, respectively. When integrated into an initial PVK/c-Si tandem, the resulting cell achieves a PCE of 29.38%. To compare the performance, the heterojunction PVK layer is replaced with an n-p homojunction PVK layer, revealing the impact of the absence of a surplus built-in electric field in the perovskite film as a strong limiting factor. Further, a thorough investigation of four distinct structures for the n-p homojunction PVK cell is conducted. The four structures include a complete cell, electron transport layer (ETL)-free, hole transport layer (HTL)-free, and carrier transport layer (CTL)-free structures. The results show that the CTL-free structure has significant potential after applying certain optimization techniques that result in reducing surface recombination, enhancing the built-in electric field, and improving light absorption. With the current-matching condition achieved, the tandem efficiency reaches 36.37%.

Abstract This paper studies the effect of adding Magnesium Oxide (MgO) and Titanium Dioxide (TiO2) nano particles to enhance the properties of hip joint bone cement. Related to previous work of enhanced bone cement properties by using MgO and TiO2, samples of composite bone cement using three different ratios (0.5%, 1% and 1.5%) w/w of MgO and TiO2 were prepared to calculate the best enhancement ratio. Hardness, compression and bending tests were calculated to check the mechanical properties of pure and composite bone cement. The surface structure was studied using Fourier transform infrared spectroscopy (FTIR) and Field emission scanning electron microscopy (FE-SEM). Setting temperature, porosity and degradation were calculated for each specimen ratio to check values match with standard range of bone cement. Results show remarkable improvement for mechanical and surface structure properties with acceptable changes in FTIR, setting temperature, degradation percentage and bending test relative to pure bone cement.

AbstractThis paper examines the effect of temperature variation on the surface triangular grating of the surface plasmon polariton (SPP) on the effectiveness of the entire array of silicon thin-film solar cells. Thin-film solar cells’ optical and electrical characteristics are examined using the electromagnetic and semiconductor models. The 3D Multiphysics simulator is used to present this study. The MATLAB/SIMULINK model based on mathematical formulas is developed to simulate the entire array of solar cells with thin films. This approach is suggested for quickly simulating the thin-film array. The presented model was applied on thin-film solar cells with and without SPP depending on the complete cell parameters from the COMSOL Multiphysics model. The triangle’s SPPs accomplish a 14.76% efficiency increase of 1.07% over a solar cell without SPPs.