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As a typical tight sandstone gas reservoir in the Ordos Basin, the second member of the Shanxi Formation in the XQ gas field in the Ordos Basin has had rich gas reservoirs and good development effects in the past. On the basis of previous studies, this paper brings new understanding to the sedimentary model of this area. Nine kinds of single lithofacies and seven kinds of lithofacies combinations are determined. Braided fluvial fan deposits in distributive fluvial systems likely developed in this area. The study area is part of the middle subfacies of this sedimentary facies, and five kinds of sedimentary microfacies environments developed. Finally, establishing sedimentary model based on sedimentary characteristics. The braided fluvial fan sedimentary model based on DFS is of great significance for deepening the understanding of terrestrial sedimentary systems and providing guidance for the exploration and development of oil and gas bearing basins. [ABSTRACT FROM AUTHOR]

In this paper, we introduce general sequence of twice-iterated Δw -(degenerate) Gould–Hopper Appell polynomials (TI-DGHAP) via discrete Δw -Gould–Hopper Appell convolution. We obtain some of their characteristic properties such as explicit representation, determinantal representation, recurrence relation, lowering operator (LO), raising operator (RO), difference equation (DE), integro-partial lowering operator (IPLO), integro-partial raising operator (IPRO) and integro-partial difference equation (IPDE). As special cases of these general polynomials, we present TI degenerate Gould–Hopper Bernoulli polynomials, TI degenerate Gould–Hopper Poisson–Charlier polynomials, TI degenerate Gould–Hopper Boole polynomials and TI degenerate Gould–Hopper Poisson–Charlier–Boole polynomials. We also state their corresponding characteristic properties. [ABSTRACT FROM AUTHOR]

This paper presents a complete investigation into the phenomenon of dual convection flow within a bulging enclosure along with non-Newtonian power-law fluids and employs the Galerkin finite element method for simulation. The main objective is to study the heat and mass transfer and entropy generation within the enclosure. Various factors, such as the Rayleigh number, power law coefficient, Lewis number, and effects of magnetic inclination are evaluated for their influence on flow dynamics and heat distribution. The study also investigates the relationship between these parameters and entropy generation, providing insights into the irreversible processes within the system. A comparative analysis of averaged Nusselt and Sherwood coefficients reveals distinct thermal and fluidic behaviours across varying powerlaw indices, emphasizing differences between shear thickening, shear thinning, and Newtonian fluid behaviours. The findings provide valuable insights into non-Newtonian power-law fluids in complex flows, enhancing our understanding of flow and heat transfer in bulging enclosures. [ABSTRACT FROM AUTHOR]

Higher-order nonlinear wave models have been a source of attraction to a huge number of researchers in recent times as a result of their significance in mathematical physics, other nonlinear sciences as well as engineering. In consequence, we outline in this paper the analytical studies entrenched on a generalized structure of a nonlinear breaking soliton equation with higher-order nonlinearity in four variables which have applications in science as well as engineering. Lie group theory is utilized to generate an 11-dimensional Lie algebra associated with the equation under consideration and in addition one parametric group of transformations related to the algebra is calculated. Besides, the technique is further invoked in performing reductions of the various subalgebras of the understudy model. Moreover, in conjunction with the theory, the direct integration technique is engaged to secure an analytic solution of the equation and as a result, a general analytic solution with regard to the second-kind elliptic-integral function is furnished. Moreover, we engage the novel simplest equation technique to gain more general solutions to the equation. In consequence, solitonic solutions comprising periodic, dark-bright, topological kink as well as singular solutions are achieved. We complemented that by exhibiting the dynamics of the secured solutions with the aid of graphical representations. In conclusion, we calculate conserved quantities associated with the aforementioned equation by invoking the well-celebrated classical Noether theorem technique. [ABSTRACT FROM AUTHOR]

In this paper, we explore local dynamics at equilibrium points, the existence of bifurcation sets and codimension-one bifurcation analysis of a discrete prey–predator system with Holling typeII functional response. Further, OGY and Hybrid control strategies are utilized to control chaos in the under study discrete model due to the occurrence of Neimark–Sacker and flip bifurcations. Finally, numerical simulations are given to verify theoretical results. [ABSTRACT FROM AUTHOR]

This paper intended to study the mechanism and active ingredients of ACB anti-epilepsy. The antiepileptic activity of ACB validated in PTZ kindled rats, ACB could increase the seizure latency and reduce seizure duration, attenuate spatial learning and memory deficits, improve hippocampus neuronal damage and regulate unbalanced neurotransmitters. Furthermore, network pharmacology and molecular docking analysis predicted four potential active compounds, in addition, PI3K/Akt signal pathway may be the main signal pathway of ACB anti-epilepsy. In vitro, ACB greatly increased the vitality and reduced apoptosis of PC12 cells exposed to H2O2. Additionally, ACB elevated Bcl-2 and downregulated C-caspase-3 and Bax proteins expression. Importantly, ACB improved the phosphorylation of PI3K and Akt in H2O2-stimulated PC12 cells, and stimulated the nuclear transfer of Nrf2. These findings indicated that ACB has effective on antiepileptic by activating of the PI3K/Akt/Nrf2 pathway to reduce oxidative stress and neuronal cell apoptosis. [ABSTRACT FROM AUTHOR]

Control charts play a vital role in process monitoring to ensure the product’s desired standards. Due to rapid improvements in data collection methods, multivariate charts are preferred over univariate charts. This paper proposes a bivariate exponentially weighted moving average chart for the simultaneous monitoring of the mean vector of Gumbel’s bivariate Pareto type II (also known as the Lomax distribution) time-between-events data. The performance of the proposed chart is assessed through average run length, median run length, and the standard deviation of the run length criteria. To show the implementation of the chart in the real world, illustrative examples are also presented. [ABSTRACT FROM AUTHOR]

In this paper, the accurate closed-form solutions of the Manakov-system are extracted via the extended (G ′ G 2 ) -expansion method, the exp ⁡ (− ϕ (Ω)) -expansion method and generalized Kudryashov method. The solutions are obtained in the form of trigonometric, hyperbolic and rational functions. The dynamical behaviour of obtained solutions is discussed by plotting 3D graphs, 2D contour graphs and density graphs. The symbolic softwares such as Maple and Mathematica are used to plot the graphs of retrieved solutions. The modulation instability (MI) of Manakov-system is also discussed in this paper. [ABSTRACT FROM AUTHOR]

The study was conducted to test the viability and pathogenicity of different forms of Alternaria solani inoculum stored at different conditions and time intervals for a period of 16 months. The aim was to confirm the survival period of pathogen in soil and to determine the simplest method to maintain inoculum in laboratory for further studies. The cultures stored at 5 °C for 2, 4, 8 and 16 months were pathogenic, while cultures stored at room temperature turned non-pathogenic after 4 months. All 6 successive sub-cultures retained viability and virulence. All the target-spots stored at 5 °C were viable after all time intervals as tested by culturing and subsequent spray of harvested mycelial suspension, but at the room temperature (RT), 16 months old inoculum lost viability and virulence. The powdered tissue samples of target-spots stored at 5 °C were found pathogenic by spray method after all the intervals of the time but, at RT 16 month old sample lost virulence. In inoculation by soil splashing, powdered tissue stored in paper bag at 5 °C retained pathogenicity till 8 months, while at RT, the inoculum stored in paper bags and the inoculum mixed in soil lost pathogenicity after 4 months. [ABSTRACT FROM AUTHOR]

A bioconvection MHD nanofluid flow which contains both nanoparticles and oxytactic bacteria is proposed. The role of oxytocic bacteria in cancer treatment is to hinder cancer development by actuating the immunity system. Oxygen-repellent bacteria as, a targeted drug delivery carriers towards infected cells, seem to be a promising tool in the fight against tumours. To depict the flow for this situation, a laminar steady incompressible nanofluid, containing oxytactic bacteria swimming heading a horizontal circular cylinder is considered. The thermal convective boundary conditions with variable physical parameters are taken. A numerical pseudospectral method is utilized. There is a considerable harmonization between the present outcome and some published papers. The current paper is supposed to give a serious understanding and deeper insight that can help develop drug-delivery applications in fluid encompassing hypoxic growth cells. [ABSTRACT FROM AUTHOR]

Nonlinear partial differential equations (NLPDEs) have been of great interest in recent years due to their numerous applications. While there are several methods for finding exact solutions to various NLPDEs, more solutions are still required. This paper first proposes the Cham method, a new method for solving NLPDEs that can generate eight families of solutions. The method is then successfully employed to solve the (2+1)-dimensional Bogoyavlenskii's breaking soliton equations. The dynamic behaviour of these equations and the bifurcation of traveling waves are also discussed. Finally, we graphically depict some solutions corresponding to some discovered solutions with different coefficient values. The Cham method is general, effective, and adaptable to many NLPDEs. [ABSTRACT FROM AUTHOR]

The present paper investigates the heat transfer features of a viscous fluid in an unsteady incompressible Casson fluid flow through a porous medium with an internal heat source under the influence of a magnetic field. A Casson fluid passes through the given porous medium using Darcy model. The study involves simulating the flow using mathematical models based on conservation laws and similarity transformations. The resulting highly nonlinear coupled ordinary differential equations are solved using the Bernoulli wavelet numerical approach. The study utilizes graphical tools to illustrate the flow behaviour under different physical factors, including the effect of the internal heat source. The normalization of the flow behaviour by the magnetic field suggests that it could potentially be used to control various flows. The study finds that various physical parameters which affects the velocity and temperature profiles of the fluid. [ABSTRACT FROM AUTHOR]

In this paper, exp (− ϕ (τ)) -expansion method, modified extended tanh-function method and Kudryashov method are used to investigate the exact solutions of the coupled Benjamin–Bona–Mahony–KdV (BBM-KdV) system. By the travelling wave transformation, the coupled BBM-KdV system is reduced to ordinary differential equations. Solving the nonlinear ordinary differential equations, kink, periodic and solitary solutions of the system are obtained. To further understand the natures of the solutions more intuitively, the dynamical behaviours of the solutions are given. The physical structures of the solutions are analysed in combination with 2D and 3D plots. These results enrich the available types of travelling wave solutions for the BBM-KdV model and are also useful for wave studies in complex engineering regions near the coast. It also proves the correctness and validity of our method. [ABSTRACT FROM AUTHOR]

This paper reveals the conformable fractional space-time perturbed Gerdjikov-Ivanov (GI) equation, which is applied to nonlinear fibre optics together with photonic crystal fibres. The foremost intent of our operation is adopting the unified method, the modified F-expansion method and the modified Kudryashov method to hunt for definite solutions to the equation. In addition, by selecting fairish values, fluctuation behaviours of the solutions are drafted. [ABSTRACT FROM AUTHOR]

This paper presents the strength and micro-structural characteristics of high plasticity expansive clay stabilized with ordinary Portland cement (OPC) and geopolymers. Furthermore, sustainability aspects such as cost-efficiency, energy consumption and eco-efficiency of the OPC and geopolymer-stabilized soils were compared. The experimental results revealed that the geopolymer-stabilized soils exhibit higher strength and sustainability performance than the OPC-stabilized soils. This study also explores the developed machine learning prediction models of the geopolymer soils' unconfined compressive strength (UCS) based on experimental data from current research and previous literature. Linear regression (LR), K-nearest neighbour (KNN), random forest (RF), random forest with random search hyperparameter optimization (BRRF) and random forest with grid search hyperparameter optimization (BGRF) were used as part of ensemble algorithms to predict stabilized soils UCS. Eight parameters such as liquid limit (LL), plasticity index (PI), ground granulated blast furnace slag (S) content, fly ash (FA) content, the molarity of NaOH (M), activator to binder ratio (A/B), Na/Al and Si/Al were used as input to predict UCS of geopolymer soils. The following metrics were used to assess the models' predictive ability for compressive strength: coefficient of determination (R2), root mean square error (RMSE), mean absolute error (MAE) and mean square error (MSE). The BRRF model has a good potential to predict the UCS of geopolymer soils, according to the findings of its testing (MAE = 0.27, MSE = 0.21, RMSE = 0.46, R2 = 0.99) and training (MAE = 0.78, MSE = 1.48, RMSE = 1.23, R2 = 0.96) phases. According to the RF model's feature importance study, slag content and liquid limit were found to influence forecasting compressive strength, while fly ash content has the least influence. [ABSTRACT FROM AUTHOR]

The present paper reports on the effects of Aluminum-doping on the micro-structural and dielectric properties of La0.7Sr0.25Na0.05Mn0.95Al0.05O3 ceramics. The analyses of the X-ray diffraction data by the Rietveld refinement technique confirmed the formation of a rhombohedral phase in the R 3 ¯ c space group. The dielectric properties were analyzed by the complex impedance spectroscopic techniques in a wide temperature extent and a spectral range between 2 kHz and 1 MHz. The Nyquist diagram with a single semicircular arc is explained by the contribution of two conducting phases associated with the effects of grains and grain boundaries. The conductivity spectrum obeyed Jonscher's power law and the conduction mechanism was attributed to the correlated barrier hopping mechanism. The dielectric parameters such as the dielectric constant (ε″) showed a compositional dependence, indicating the prevalence of inter-grain conductive contribution and microstructural features which can be interpreted by the Maxwell–Wagner process. [ABSTRACT FROM AUTHOR]

In this paper, we present an effective method under Taylor wavelets and collocation technique to find an approximate solution of linear and non-linear second-order singular value differential equations. Application of this method on various problems confirms the efficiency, easy applicability, and rapid computation. The obtained solution is compared with some other existing numerical solutions. For many problems, this method gives a solution same as the exact solution of the problem which confirms the effectiveness and accuracy of this method. Additionally, we include graphs and figures to demonstrate that the Taylor wavelet method offers better accuracy for a number of problems. MATLAB software is used to process relative data and execute calculations. [ABSTRACT FROM AUTHOR]

Copper ferrite (CuFe2O4, CF) and silver-doped copper ferrite (Ag-CuFe2O4, ACF) were prepared via co-precipitation method. While nano-composite of ACF with rGO was prepared by ultra-sonication approach. Degradation of crystal violet (CV) and benzoic acid (BA) by CF, ACF, and ACF@rGO was conducted under sunlight. Because of tremendous stability and immense surface area of rGO, it shows good ability to transfer electrons during photocatalysis.Band gap for CF and ACF were tuned having values 1.36 and 1.67 eV. Ag-CuFe2O4@rGO has exhibited greater photo-catalytic activity than a bare and doped sample. 82.7% and 48.4% were degradation % of CV and BA by Ag-CuFe2O4@rGO respectively. Ag-CuFe2O4@rGO showed 1.3 times higher efficiency than bare CuFe2O4. ACF was sonicated with rGO and composite was formed which was not reported before and I was the novelty of this paper. The photodegradation ability and cyclic stability etc. was increased after the formation of composite. [ABSTRACT FROM AUTHOR]

This paper aimed to examine the impact of flavonoid osajin (OSJ) on liver damage induced by sepsis. A total of 30 male rats were divided into 5 groups (Sham, sepsis, OSJ 150, OSJ 300 and reference). During sepsis, elevated lipid peroxidation (LPO) level and catalase activity (CAT) and decreased glutathione (GSH) level and superoxide dismutase (SOD) activity were observed in hepatic tissues of sepsis group in comparison with Sham group. A strong interleukin-33 and caspase-3 expressions were detected in hepatic tissues of sepsis group. On the contrary, OSJ administration to OSJ 300 group showed a significant decrease (P < 0.001) in LPO level (176±2.926) and significant increase (P < 0.001) in GSH level (10.586±0.083) and SOD activity (29.152±0.094) in comparison with sepsis group (185.777±1.735, 8.246±0.124, 24.307±0.379 respectively). In addition, the consumption of OSJ reduced expressions of interleukin-33 and caspase-3 and improved histopathological integrity. In conclusions, OSJ has hepatoprotective effect against sepsis-induced liver injury. [ABSTRACT FROM AUTHOR]

A new area of research called intuitionistic fuzzy soft expert set is expected to overcome the drawbacks of an intuitionistic fuzzy soft set in terms of eligibility for soft expert-argument approximate function. This type of function views the power set of the universe as its co-domain and the cartesian product of attributes, experts, and their opinions as its domain. The domain of this function is larger as compared to the domain of a soft approximation function. It can manage a situation in which several expert opinions are taken into account by a single model. For the soft expert-argument approximate function with intuitionistic fuzzy setting, concepts such as set inclusion, (α , v) -convexity(concave) sets, strongly (α , v) -convexity (concave) sets, strictly (α , v) -convexity (concave) sets, convex hull, and convex cone are conceived in this paper. Some set-theoretic inequalities are established with generalized properties and results on the basis of these specified notions. Additionally, by using a theoretic cum analytical approach, various elements of computational geometry, such as convex hull and convex cone, are theorized and some pertinent results are generalized. [ABSTRACT FROM AUTHOR]

In this paper, our aim is to further expand the use of the two-variable (G ′ / G , 1 / G) -expansion approach to a new coupled KdV and Z-K system, which has various significant applications in different fields of applied sciences. The KdV equation, along with shallow-water waves and long internal waves in oceans, basically explains how long, one-dimensional waves propagate in a variety of physical conditions. The study of coastal waves on the basis of the ocean is done using the Zakharov–Kuznetsov (Z-K) equation and this model is utilized to illustrate ion-acoustic wave propagation. By using this method, different forms of analytical solutions of the new coupled KdV (NCKdV) system and the new coupled Z-K (NCZ-K) system, such as solitons, multi-peak solitons, solitary waves, trigonometric, hyperbolic and rational functions and other wave solutions are constructed. The significant features of multi-peak solitons induced by the higher-order effects, including velocity variations, localization or periodicity attenuation and state transitions, are revealed. When the localization disappears then the multi-peak soliton becomes a periodic wave. The constructed solutions are also presented graphically having their applications in engineering, etc. The stability of the solution is examined by utilizing modulation instability. The results obtained show that the proposed technique is universal and efficient. In addition, this technique can also be applied to lots of other new coupled systems arising in other areas of applied sciences. [ABSTRACT FROM AUTHOR]

Many papers have shown that fractional derivatives are preferable to other operators when the data or information is exact, but this is not the case in practice because we live in an uncertain environment. Fuzzy operators are the best option for modelling in this situation. In this paper, we use the fuzzy fractional Caputo's derivative to generalize the fractional-order human liver model. We consider both types of H-differentiability (type 1 and type 2). We establish a general procedure of solution under the concept of H-differentiability through fuzzy Laplace transform. We implement the proposed scheme to derive the numerical results of the model. We present the archived theoretical solution via two- and three-dimensional graphs at different values of fractional orders and specific fuzzy triangular initial conditions. We present the evolution of the proposed model for some values of φ 0 ∈ [ 0 , 1 ] to see the effect of uncertainty on the secretion of Bromsulphthalein in the blood and liver. [ABSTRACT FROM AUTHOR]

In this paper, a basic solvothermal synthesis using sodium tungstate as a precursor is reported to prepare tungsten oxide (WO3) particles. XRD data confirmed the highly crystalline nature. The broad peaks of XRD patterns estimated the nanocrystallites of WO3. The average crystallite size as was 95 nm. Scanning electron microscopy showed the morphologically cube-like particles with aggregation that was converted to larger brick-like particle of WO3 after calcination. WO3 was used as fuel additive in diesel oil. Fire and flash points of diesel oil were enhanced to 49°C and 54°C respectively. The calorific value was increased up to 36580 Jg−1. Thus fuel efficiency was enhanced by use of WO3 as an additive. The use of different concentrations of WO3 (20, 40, 60, 80 ppm) as fuel additive has been also explored in this paper. The observed additive properties of WO3 suggested the potential applications of such metal oxides. [ABSTRACT FROM AUTHOR]

In this paper, we obtain the Euler-Lagrange equations for different kind of variational problems with the Lagrangian function containing the Riesz-Hilfer fractional derivative. Since the Riesz-Hilfer fractional derivative is a generalization for the Riesz-Riemann-Liouville and the Riesz-Caputo derivative, then our results generalize many recent works in which the Lagrangian function involving the Riesz-Riemann-Liouville or the Riesz-Caputo derivative. We also study the problem in the presence of delay derivatives and establish a version for Noether theorem in the Riesz-Hilfer sense. In order to achieve our aims we derive some formulas to integration by parts for the Riesz-Hilfer fractional derivative. In the last section, examples are given to clarify the possibility of applicability of our results. In order to clarify the significant conclusions of the paper, we refer to our techniques enable to study many different variational problems containing the Riesz-Hilfer derivative. [ABSTRACT FROM AUTHOR]

The modified first Zagreb connection index Z C 1 ∗ is a graph invariant, initially appeared within a formula of the total electron energy of alternant hydrocarbons in 1972, and revisted in a recent paper [A. Ali, N. Trinajstić. A novel/old modification of the first Zagreb index. Mol Inform. 2018;37(6). Art# 1800008; arXiv:1705.10430 [math.CO]]. In this paper, the graph(s) with the maximum/minimum Z C 1 ∗ value is/are characterized from the class of all n-vertex trees with fixed number of segments. As the number of segments in a tree can be determined from the number of vertices of degree 2 (and vice versa), the trees with the extremum Z C 1 ∗ values are also determined from the class of all n-vertex trees having a fixed number of vertices of degree 2. [ABSTRACT FROM AUTHOR]

In our present study, we approach a linear theory for the thermoelasticity of type III for Cosserat media. At the beginning we introduce the equations and conditions, specific for a mixed problem in this context, namely the motion and energy equations, the initial condition and boundary relations. After that, we establish two results regarding the solution unique to the problem and two results on the continuous dependence of solutions, for the same mixed problem. Both problems that we address in our paper (uniqueness and continuous dependence) are not based on the material symmetries of the medium. Moreover, our results concern the theory of type III thermoelasticity for Cosserat media in their most general form, namely anisotropic. [ABSTRACT FROM AUTHOR]

This paper discusses some methods based on the random search problem over the bound domain. The particle moves randomly with a bounded two-dimensional stochastic process in a bounded area. The physical phenomenon determines the boundaries of this area. We have a smart nanosensor tracks randomly for this particle. The necessary condition that maximizes the probability of the first meeting time between the nanosensor and the particle is derived. [ABSTRACT FROM AUTHOR]

In this paper, we show that for semi-prime rings of two-torsion free and 6-centrally torsion free, given a multiplicative centrally-extended derivation δ and a multiplicative centrally-extended epimorphism ϕ we can find a central ideal K and maps Δ , Φ : S / K → S / K such as Δ and Φ are multiplicative derivation and multiplicative epimorphism, respectively. [ABSTRACT FROM AUTHOR]

Cancer is a fatal disease for a very long time. It has its own history. Now it has become one of the major reasons for death due to its various types. Researchers, scientists and doctors are trying to find out the success and minimize the death rate in this field. The fact is, cancer treatment is only effective when it has been diagnosed at a very early stage. Therefore, cancer is a kind of provocative topic for analysis. In this paper, we have shown the growth of cancer cells, normal cells along with chemotherapeutic cells. We have shown that the effect of chemotherapeutic drugs is highest at the centre of tumour affected area. We have used the Yang–Abdel–Cattani fractional operator with Laplace transform for all numeric calculations. Apart from numerical calculations, we have also shown the graphical representation of cell growth. [ABSTRACT FROM AUTHOR]

In this paper, wet-chemically synthesized hierarchical NiO microspheres and their exfoliated (ExC)-based nanocomposites (NiO/ExC) as electrodes for supercapacitor applications have been reported. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and Scanning electron microscopic (SEM) techniques were used to characterize the as-synthesized products. The study of PXRD revealed that NiO exhibits a cubic phase. Morphological analysis showed a hierarchical micro-spherical structure of mesoporous NiO particles. The as-synthesized hierarchically porous NiO manifested a specific capacitance of 331 F/g with 50% capacitance retention. But, exfoliated carbon (ExC)-based nanocomposite (0.07 g NiO/0.003 g ExC) showed a particular capacitance of 815 F/g at the scan rate of 5 mV/s, with 79% retention in capacitance. High electrical conductivity and larger surface area arising from synergistic effects between NiO and exfoliated carbon resulted in a tremendous electrochemical response of NiO/ExC nanocomposites. The inclusion of the ExC further improves electrical impedance spectroscopic results by facilitating the charge transfer. [ABSTRACT FROM AUTHOR]

In this paper, a class of the two-dimensional (2D) mathematical models of the time fractional telegraph equation with spatial variable coefficients is considered. These models include the 2D time fractional telegraph equation (2D-TFTE), the 2D time fractional diffusion wave equation with damping (2D-TFDWED) and the 2D time fractional wave equation (2D-TFWE). The fractional derivatives are described in the Caputo sense. A novel spectral technique is used to solve the aforementioned models. The technique is based on the operational matrices of the shifted Gegenbauer polynomials in conjunction with the spectral tau method. The product of operational matrices of the space vectors is constructed in a simple way to remove the obstacle that facing the use of the tau method in solving the variable coefficients fractional/integer order PDEs. Miscellaneous numerical experiments are offered to verify the accuracy and rapid rate of convergence of the presented numerical technique. [ABSTRACT FROM AUTHOR]

In this paper, we provide a solution to the Cahn–Hilliard equation using the q-homotopy analysis method (q-HAM). The q-HAM is a more general, simple and widely used method for solving stiff nonlinear partial differential equations. The Cahn–Hilliard equation is a classical model in material sciences that describe spinodal decomposition and phase separation in two-phase flows. Using the q-HAM, the effect of various parameters of physical interest such as diffusive parameter, thickness parameter, advection and reaction terms on concentration is studied. The comparison of the computed solution with the exact solution is presented for some fixed parameter values to validate the solution obtained using the q-HAM. [ABSTRACT FROM AUTHOR]

We present a paper on the different methods for finding solutions to the Caudrey–Dodd–Gibbon equation with variable coefficients, which has wide applications in quantum mechanics and nonlinear optics. We have studied the equation analytically by using the unified method and the modified Kudryashov method. With the aid of symbolic computation and several types of auxiliary equations, we have obtained soliton solutions and other solutions. Then, we assign different values to the parameters, generating two-dimensional and three-dimensional graphics of the solutions, and discuss the interaction of several groups of solion solutions to form periodic wave solutions and kink solitary wave solutions. [ABSTRACT FROM AUTHOR]

In this paper, four groups of polyvinyl alcohol fibre-reinforced geopolymer composites containing various content of nano-alumina particles were investigated. Results showed an improvement in geopolymer fracture toughness, compressive, impact and flexural strength with the added nano-alumina particles as compared to the control specimen. Flexural strength increases as the weight ratio of nano-alumina particles increases from 0.0 to 2.0 wt% and then decreases to 6.50 MPa at 3.0 wt%. Geopolymer reinforced by 2.0 wt% of nano-alumina (PVAGNC-2) displayed the highest flexural and compressive strength of 7.51 and 23.48, respectively. PVAGNC-2 exhibited the highest mechanical (compressive, flexural, impact and hardness) properties. Scanning Electron Microscopy examination showed that the PVAGNC-2 microstructure is compacted with fewer pores indicating the probability of PVAGNC-2 to display great compressive strength and excellent mechanical resistance to the external force needed for construction. [ABSTRACT FROM AUTHOR]

Vertebrate fossils/remains became recently significant in various study fields for determining the ecological biodiversity. However, with the great abundance of fossils/remains and their classes, there is a difficulty in identifying and detecting these classes. Hence, in this paper, an accurate machine learning classification technique is presented to differentiate automatically some types of 3D vertebrate remain images. A computed tomography (CT) scanner is utilized to construct a dataset of 3D images of some vertebrate remains found in Egypt. Adaptive enhancement and segmentation processes are applied to the dataset. The different selected geometric features are then extracted. Thus, the extracted features are classified using suitable machine learning classifiers (SVM, KNN, DTs). The automatic detection for the remains class, according to the extracted features, is obtained using the confusion matrix for the training and testing data points and the receiver operating characteristic (ROC) curve. The results confirmed an accurate technique with high performance. [ABSTRACT FROM AUTHOR]

The objective of this paper was to study and analyze the performance of a micro Wind – Solar Hybrid Generator (WSHG) in the Kingdom of Saudi Arabia (KSA). The WSHG consists of a micro wind solar system connected to a secondary distribution grid. The system was tested in two locations in the KSA namely DAMMAM and HA'IL and used the wind speed and solar radiation of two periods of the year. Two operating modes were discussed for the system: the Normal Operating Mode (NOM) and the Default Operating Mode (DOM). The simulation results showed the best performance of the system during the two periods of the year, in the two locations of the KSA, and in the two operating modes. The experimental measurements of the WSHG have been carried out and showed the similarity between the measured and simulated values of the output inverter voltage and of the DC-link voltage. [ABSTRACT FROM AUTHOR]

In this paper, a modified Korteweg–de Vries equation with a quartic nonlinear term in two-electron temperature plasmas is studied. Firstly, the symmetries are constructed using the generalized symmetry method. In addition, the potential equation is studied, it can been found that this equation does not posses potential symmetries. Meanwhile, the symmetry reduction and group-invariant solutions are derived rely on the one-dimensional optimal system of subalgebras. Finally, conservation laws are showed resort by the multipliers method, three polynomial type conserved quantities are presented, also the Hamiltonian form is obtained. In particular, reciprocal Bäcklund transformations for conservation laws are obtained for the first time. [ABSTRACT FROM AUTHOR]

This paper seeks to estimate the entropy for the inverse Weibull distribution using progressively Type-II censored data. To reach this objective, the entropy is defined through three entropy measures, namely, Rényi, q-entropy and Shannon entropy, and two estimation methods are used to estimate them. The first approach to estimate these quantities is the method of maximum likelihood. Furthermore, and for the first time, we consider the method of maximum product of spacing to estimate the mentioned entropy measures. Also, a simulation study is carried out and two real data sets are analysed. The numerical outcomes showed that the maximum likelihood provides good point estimates while the interval estimates based on the maximum product of spacing method have the shortest confidence interval lengths. [ABSTRACT FROM AUTHOR]

Response surface designs are generally used in process/product optimization studies. Sequential third-order response surface designs are advantageous when the experimenter encounters the significance of lack of fit of a fitted second-order model while establishing the relationship between the input and response variables. In some experimental situations, responses pertaining to certain design points may be destroyed or unobtainable or inaccessible. The unavailability of the observations pertaining to certain experimental run(s) affects the design property and affects the analysis of variance. In this paper, we have examined the robustness of sequential third-order rotatable design and investigated the loss of information when one or two observations pertaining to experimental run(s) is (are) missing, which are at different radii from the design centre. It has been found that the maximum loss of information occurs when the observation at the design points which are at higher radii from the design centre is lost and the design has the minimum efficiency. [ABSTRACT FROM AUTHOR]

A technological scheme was developed to produce 2G fermentable sugar from sugarcane bagasse and was assessed for the process feasibility. This paper describes recovery of fermentable sugar, characterization of pretreated hydrolysed bagasse, in-silico elucidation of enzymatic hydrolysis and techno-economic analysis of the recovery of sugar from bagasse. The in-silico approach included characterization of both the enzymes, estimation of physiochemical and functional properties through ProtParam. Secondary structures of enzymes were represented using SOPMA. Modelling of enzymes was done using MODELLER 9.24. The developed model was validated through PROCHECK and was evaluated using Verify3D. The active sites of both the enzymes were predicted using 3D LigandSite – Ligand binding site prediction server and molecular docking of the predicted Models were performed using Swiss Dock. The techno-economic analysis showed 0.516 kg (2G fermentable sugar)/kg bagasse). [ABSTRACT FROM AUTHOR]

Near-surface geophysical techniques, (i.e. ground-penetrating radar (GPR) and electric resistivity tomography (ERT)), continue to enable great possibilities for 3-D visualization of fractures and cavities. An integrated survey, including GPR and ERT, was used for mapping and evaluating a complex subsurface fracture network in Eocene limestone at Al-Mokattam site, Egypt. While only GPR was available to investigate an engineering site of about 200 × 300 m, located in Riyadh city, Saudi Arabia, for cavity detection. At the Egyptian site, GPR data were acquired with a GSSI SIR2000 system using a 400 MHz shielded antenna with 0.2 m in-line spacing. GPR data visualized using an isosurface rendering combined with inverted ERT allowed us to identify and follow the fracture system, which was mainly filled with low-resistivity sediment; such fractured limestone may cause landslides. GPR data at the Riyadh site were acquired using the RAMAC system with a 100 MHz shielded antenna attached to a GPS with real-time kinematic total station equipment; GPR data confirmed the possible presence of cavities at different depths, which may cause severe damage during building construction. In this paper, we demonstrated the efficiency of each geophysical technique available for solving subsurface engineering problems, leading to future improvements in site safety. Additionally, we indicated the efficiency of an advanced 3-D GPR visualization technique (isosurface rendering) for improving fracture and cavity detection, characterization and interpretation. [ABSTRACT FROM AUTHOR]

In the present paper, we are concerned by some investigation on circular restricted three-body problem (CR3BP), where we assume that the primaries have variable masses and variable charges. Among the principal tools used in the present study, we cite the well known Meshcherskii transformation. We have derived the equations of motion and Jacobi integral which differ by variation constant k and charge q from the classical restricted three-body problem. More exactly, in this paper, we have drawn the equilibrium points, the zero-velocity curves, the periodic orbits, the surfaces and the basins of attraction for the different values of charge. We have found one equilibrium point when the charge is q=0.4 and three equilibrium points when its value is q=0.501. We also have drawn the periodic orbits for these two values of charge and found that they are periodic. We have also plotted the zero-velocity surfaces for these two values of charges and found a tremendous variation in these two surfaces. We notice that the Poincaré surfaces of section are shifting away from the origin, when we increase the value of charge. We also got different surfaces for the motion of infinitesimal body, with respect to the variations of charge. The basins of attraction have been drawn for these two values of charge by using Newton-Raphson iterative method. We also noticed that by increasing the values of charge, the basins of attraction are shrinking. For the stability of the equilibrium points that we have studied, we found that, among them, one is stable and three others are unstable. [ABSTRACT FROM AUTHOR]

In this paper, we consider a non-linear stochastic differential delay equation (SDDE) of second order. We derive new sufficient conditions which guarantee stochastically stability and stochastically asymptotically stability of the zero solution of that SDDE. Here, the technique of the proof is based on the definition of a suitable Lyapunov-Krasovskii functional, which gives meaningful results for the problem under consideration. The derived results extend and improve some result of in the relevant literature, which are related to the qualitative properties of solutions of a SDDE of second order. The results of this paper are new and have novelty, and they do a contribution to the topic and relevant literature. As an application, an example is given to show the effectiveness and applicability of the obtained results. Finally, by the results of this paper, we extend and improve some recent results that can be found in the relevant literature. [ABSTRACT FROM AUTHOR]

This paper analyzes the stability, uniformly stability, asymptotically stability, boundedness, uniformly boundedness and square integrability of solutions of a system of differential equations of second order with variable delay by applying the direct method of Lyapunov- Krasovskii. By means of a new Lyapunov-Krasovskii functional, we simplify and extend some previous work that is found in the recent literature. Finally, the validity and applicability of the proceeded results are indicated by some numerical examples applying MATLAB-Simulink. By the results of this paper, we can obtain the results of Omeike et al. [Stability and boundedness of solutions of certain vector delay differential equations. J Nigerian Math Soc. 2018;37(2):77–87], Theorem 1.1 and Theorem 1.2, under weaker conditions. In addition, we establish two new results on the uniformly stability and integrabilty of solutions the considered equation. Finally, in particular cases, the applicability of the results of this paper can be shown by two new examples. These are the contribution of this paper to the subject and the relevant literature. [ABSTRACT FROM AUTHOR]

In this paper, an efficient spectral collocation method is presented for solving the space–time variable-order fractional advection–dispersion equations (ST-VO-FADE). The proposed method is based on the Legendre collocation spectral procedure together with the Legendre operational matrices for fractional derivatives, described in the sense of Riemann–Liouville and Caputo. The main characteristic behind this approach is to reduce such problems to those of solving systems of algebraic equations in the unknown expansion coefficients of the sought-for spectral approximations, which greatly simplifies the solution process. The validity of the method is demonstrated by solving two numerical examples. Finally, comparisons between the algorithm derived in this paper and the existing algorithms are given, which show that our numerical schemes exhibit better performances than the existing ones. [ABSTRACT FROM AUTHOR]

In this paper, fractional optimal control problem for two-dimensional coupled diffusion system with final observation is investigated. The fractional time derivative is considered in Atangana–Baleanu sense. Constraints on controls are imposed. First, by means of the classical control theory, the existence and uniqueness of the state for these systems is proved. Then, the necessary and sufficient optimality conditions for the fractional Dirichlet problems with the quadratic performance functional are derived. Finally we give some examples to illustrate the applicability of our results. The optimization problem presented in this paper constitutes a generalization of the optimal control problem of diffusion equations with Dirichlet boundary conditions considered in recent papers to coupled systems with Atangana–Baleanu time derivatives. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to examine the spillover of returns, information and volatility of returns, and conditional variance-covariance between the stock markets of developed countries namely the United States of America, the United Kingdom and China (US, UK and CH) and the stock markets of Gulf Cooperation Council (GCC) countries (Kuwait, United Arab Emirates, Qatar, Saudi Arabia, Oman, and Bahrain) using daily returns spanned from 2 March 2003 to 9 December 2010. We consider shocks and volatility spillover model by applying a multivariate generalized autoregressive conditional heteroskedasticity (MGARCH) model using; MGARCH-BEKK to identify the source and magnitude of volatility and shock spillover. We get the correlation between GCC markets is positive, indicating that there is a common factor which is driving the markets towards the same direction. Evidence shows that the own-shocks and volatility in GCC markets are highly significant. Cross-information spillover effects, as another observable trend, are found between Qatar and Oman. Furthermore, the results show that UA is significantly affected by spillover (return, shocks and volatility) from developed markets, while there have been no significant effects seen from Kuwait markets. This study takes a new empirical look in the sense that the models incorporating all the countries under investigation are estimated jointly utilizing multivariate GARCH-BEKK formulation. In addition, this paper should be interesting for academicians as well as practitioners. Including those interested in modelling multivariate volatility for financial market risk management. [ABSTRACT FROM AUTHOR]

In this paper, we apply the (G′/G)-expansion method based on three auxiliary equations, namely, the generalized Riccati equation G ′ (ξ) = r + p G (ξ) + q G 2 (ξ) , the Jacobi elliptic equation (G ′ (ξ)) 2 = R + Q G 2 (ξ) + P G 4 (ξ) and the second order linear ordinary differential equation (ODE) G ′′ (ξ) + λ G ′ (ξ) + μ G (ξ) = 0 to find many new exact solutions of a nonlinear partial differential equation (PDE) describing the nonlinear low-pass electrical lines. The given nonlinear PDE has been derived and can be reduced to a nonlinear ODE using a simple transformation. Soliton wave solutions, periodic function solutions, rational function solutions and Jacobi elliptic function solutions are obtained. Comparing our new solutions obtained in this paper with the well-known solutions is given. Furthermore, plotting 2D and 3D graphics of the exact solutions is shown. [ABSTRACT FROM AUTHOR]

In this paper, we consider the Bessel-Struve transform on . We establish new versions of Cowling-Price's and Miyachi's theorems for the Bessel-Struve transform on . The techniques of the proofs are based on the properties of the Bessel-Struve kernel, the relation between the Bessel-Struve transform with the classical Fourier transform and on the positivity of the multi-variables Weyl and multi-variables Sonine transforms. The results of this paper are new, and they have novelty and generalize some results exist in the literature. [ABSTRACT FROM AUTHOR]

Entropy is a measure of random variable uncertainty that reflects the anticipated quantity of information. In this paper, estimation of Shannon entropy for Lomax distribution, viz unified hybrid censored data are considered. The processes of maximum likelihood and Bayesian estimation procedures are regarded. The Bayesian estimator under balanced squared error, balanced linear exponential, and balanced general entropy loss functions are derived. The purpose of a Monte Carlo simulation study is designed to compare the accuracy of different estimators in the context of specific measures. Real data analysis is employed to confirm the proposed estimators. In summary, we discovered that, according to the findings of the study, the mean squared errors values decrease as the sample size increases. In the majority of cases, Bayesian estimates under balanced linear exponential loss function are more appropriate in terms of simulation out comes than other specified loss functions. [ABSTRACT FROM AUTHOR]