Numerical Part Research Articles

On convexity analysis for discrete delta Riemann–Liouville fractional differences analytically and numerically

In this paper, we focus on the analytical and numerical convexity analysis of discrete delta Riemann–Liouville fractional differences. In the analytical part of this paper, we give a new formula for the discrete delta Riemann-Liouville fractional difference as an alternative definition. We establish a formula for the Delta ^{2}, which will be useful to obtain the convexity results. We examine the correlation between the positivity of ({}^{mathrm{RL}}_{w_{0}}Delta ^{alpha} mathrm{f} )( mathrm{t}) and convexity of the function. In view of the basic lemmas, we define two decreasing subsets of (2,3), mathscr{H}_{mathrm{k},epsilon} and mathscr{M}_{mathrm{k},epsilon}. The decrease of these sets allows us to obtain the relationship between the negative lower bound of ({}^{mathrm{RL}}_{w_{0}}Delta ^{alpha} mathrm{f} )( mathrm{t}) and convexity of the function on a finite time set mathrm{N}_{w_{0}}^{mathrm{P}}:={w_{0}, w_{0}+1, w_{0}+2,dots , mathrm{P}} for some mathrm{P}in mathrm{N}_{w_{0}}:={w_{0}, w_{0}+1, w_{0}+2,dots }. The numerical part of the paper is dedicated to examinin the validity of the sets mathscr{H}_{mathrm{k},epsilon} and mathscr{M}_{mathrm{k},epsilon} for different values of k and ϵ. For this reason, we illustrate the domain of solutions via several figures explaining the validity of the main theorem.

Reconstruction of pointwise sources in a time-fractional diffusion equation

This paper is concerned with an inverse pointwise source problem for the time-fractional diffusion equation in the two-dimensional case. The source term to be identified models the action of a finite number of small particles. Each particle is assumed to be no larger than a single point, characterized by its location and intensity. Both theoretical and numerical aspects are discussed. In the theoretical part, we analyse the well-posedness of the Dirac time-fractional diffusion problem. For the inverse problem, we establish that the unknown point sources can be uniquely identified from local measured data and we derive a local Lipschitz stability result. In the numerical part, we develop a fast and accurate reconstruction approach. The unknown pointwise sources are characterized as solution to an optimization problem minimizing a tracking-type functional. A noniterative reconstruction algorithm is devised, allowing us to determine the number, locations and intensities of the pointwise sources. The efficiency of the proposed approach is confirmed by some numerical examples.

Impact of Portable Executable Header Features on Malware Detection燗ccuracy

One aspect of cybersecurity, incorporates the study of Portable Executables (PE) files maleficence. Artificial Intelligence (AI) can be employed in such studies, since AI has the ability to discriminate benign from malicious files. In this study, an exclusive set of 29 features was collected from trusted implementations, this set was used as a baseline to analyze the presented work in this research. A Decision Tree (DT) and Neural Network Multi-Layer Perceptron (NN-MLPC) algorithms were utilized during this work. Both algorithms were chosen after testing a few diverse procedures. This work implements a method of subgrouping features to answer questions such as, which feature has a positive impact on accuracy when added? Is it possible to determine a reliable feature set to distinguish a malicious PE file from a benign one? when combining features, would it have any effect on malware detection accuracy in a PE file? Results obtained using the proposed method were improved and carried few observations. Generally, the obtained results had practical and numerical parts, for the practical part, the number of features and which features included are the main factors impacting the calculated accuracy, also, the combination of features is as crucial in these calculations. Numerical results included, finding accuracies with enhanced values, for example, NN_MLPC attained 0.979 and 0.98; for DT an accuracy of 0.9825 and 0.986 was attained.

Tensile stress development and critical behavior of a flexible barrier

A DEM numerical approach is employed to illustrate the critical stress development of a three-supporting cable flexible barrier under a large scale stony debris movement impact. A proper linear parallel bond is applied to build the flexible barrier model. Critical state is presented by lowering the tensile resistance of the flexible barrier and steepening the channel slope. The tensile stress of the supporting cables is primarily studied. Results mainly indicate that the particle-structure contact is essential to the stress development. The bottom cable always exhibits larger tensile stress due to the massive collision and compressive force of particles and the tensile force exerted by the vertical cable-net joint system. On the other hand, the intermediate cable receives lower collision and compressive force, resulting in smaller tensile stress. The bottom cable indicating numerous direct particle-structure contact part performs brittle failure, which is analogous to the concentrated load feedbacks. The loading of the intermediate one reaches ductile failure, reflecting the desirable effect of dispersing loads. This study suggests that practical engineering should try to avoid massive boulder impact or reinforce the bottom cable in order to improve the hazard prevention design.

Pricing of Basket CDS with Bilateral Default Risk under Vasicek Model with Circular Contagion

In this study, on the basis of basket CDS, we take into account the complex correlations among market participants and choose to use the contagion model to price basket CDS. This study assumes that a basket of reference assets is defaultable and that defaults between two counterparties are contagious. Without taking into account the default of the CDS buyer, we assume that both the interest rate and the default intensity of the reference assets follow the Vasicek model. We obtain the related probability density function by the PDE method. Under the no‐arbitrage principle, we set up several scenarios to get the basket CDS pricing formula. In the numerical analysis part, we verify the validity of the formula by Monte Carlo simulation, and discuss the influence of the main parameters on the formula.

Analysis of the effect of localized corrosion shape on a cracked and notched 2024 AL plate repaired with composite patch under thermo-mechanical loading

This study highlights the analysis of corrosion shape effects under thermo-mechanical loading on the development of damage in corroded and cracked aluminum plates. This study is divided into two parts, the numerical analytical part, was performed to compare the effect of the corrosion geometry on the repair and adhesive damage; We analyzed the effects of damaged areas on the level of corrosion in the adhesive layer of three composite materials (boron/epoxy, glass/epoxy, and graphite/epoxy), and studied the change of the stress intensity factor for circle or square-shaped corrosion. The second part related to an experimental study of the corrosion shape on the ultimate strength of the damaged plate repaired by the boron/epoxy composite material. The results obtained, indicated that the effect of the circular shape of corrosion is small compared to the square shape. The type of composite material (boron / epoxy) has proven its optimal effect on repair.

Performance Analysis of Voltage Multiplier Coupled Cascaded Boost Converter With Solar PV Integration for DC Microgrid Application

The voltage gain of the quadratic boost converter (QBC) increases when the duty cycle is greater than 0.70. The Voltage Multiplier Coupled Quadratic Boost Converter (VM-QBC) is derived to increase the voltage gain by increasing the numerator part of the voltage gain equation. To improve the performance of the VM-QBC, a modified VM-QBC viz., Voltage Multiplier Coupled Cascaded Boost Converter (VM-CBC) is proposed in this paper. The continuous source current, utilization of two inductors, non-inverted output voltage, improved efficiency and common ground between the input source and the load are the key merits of the proposed VM-CBC. The operation of the proposed converters in continuous and discontinuous conduction modes is studied. The performance of the proposed converters is evaluated and compared to the performance of recently reported converters. The state-space models of the proposed converters are derived, and the significant transfer function's bode plots are examined. The experimental results of a 500 W, 50 kHz, 650 V, input supply with 48 V are reported. A PI controller for the VM-CBC is designed, and the closed-loop experimental results are presented. The simulation results of the integrated VM-CBC and 3φ inverter with solar PV are also presented. The P&O algorithm controlled VM-CBC ensures the maximum power taken from solar PV.

THEORETICAL AND NUMERICAL COMPUTATIONS OF CONVEXITY ANALYSIS FOR FRACTIONAL DIFFERENCES USING LOWER BOUNDEDNESS

This study focuses on the analytical and numerical solutions of the convexity analysis for fractional differences with exponential and Mittag-Leffler kernels involving negative and nonnegative lower bounds. In the analytical part of the paper, we will give a new formula for [Formula: see text] of the discrete fractional differences, which can be useful to obtain the convexity results. The correlation between the nonnegativity and negativity of both of the discrete fractional differences, [Formula: see text] with the convexity of the functions will be examined. In light of the main lemmas, we will define the two decreasing subsets of [Formula: see text], namely [Formula: see text] and [Formula: see text]. The decrease of these sets enables us to obtain the relationship between the negative lower bound of [Formula: see text] and the convexity of the function on a finite time set given by [Formula: see text] for some [Formula: see text] Besides, the numerical part of the paper is dedicated to examine the validity of the sets [Formula: see text] and [Formula: see text] in certain regions of the solutions for different values of [Formula: see text] and [Formula: see text]. For this reason, we will illustrate the domain of the solutions by means of several figures in which the validity of the main theorems are explained.

New numerical method for solving optimal control problem for the stationary Navier-Stokes equations

<abstract><p>The purpose of this article is to propose a new numerical method to solve the problem of optimal control of the steady-state Navier-Stokes equations via the velocity-pressure formulation. We apply a new technique to derive a system of equations from which the solution can be calculated. The spectral method is used to discretize the problem. An extended relaxation method is proposed in the numerical part to ensure the correct convergence of the system. Finally, numerical results are provided to confirm the effectiveness of this approach.</p></abstract>

Experimental and numerical determination of interlayer shear strength of glass fiber-reinforced epoxy composites

This study aims to produce glass fiber composite plates by vacuum infusion method and to determine the interlaminar shear strength (ILSS) under the short beam test. For this purpose, composite plates were produced under the effect of vacuum and temperature by adding glass fiber layers on a flat vacuum table. Short beam tests were carried out on the obtained laminated composite plates and the interlayer shear strength, which is generally characterized by delamination damage, was investigated. In the numerical part, the tests were modeled using the LS-DYNA finite element package program, and the Hashin damage criterion-based material model was used to see the damages that occurred in the composite structure after the tests.

ADOPTION OF INFORMATION TECHNOLOGY IN SMALL AND MEDIUM WOMEN ENTERPRISES TO IMPROVE BUSINESS PERFORMANCE

Many small and medium enterprises (SME) owners poorly understand the relevance of information and communication technology in numerous fields. Almost all SMEs use information technology (IT) to support their administrative procedures. According to the government, the SME development success would reinforce the foundation of the populace's economy because, up to now, the work done by SMEs typically uses local resources rather than imported ones in numerous parts of Jordan. This study aims to offer suggestions for improving the competitiveness of Jordanian SMEs through a paradigm of IT adoption controlled by Cloud SaaS. The issues from this study include the following: (1) Identifying information and technology adoption and reviewing information technology adoption variables on women SMEs in Jordan; (2) Analyzing the relationship between information technology adoption variables on women SMEs in Jordan; and (3) Recommending the technology adoption model to the women SMEs in Jordan including the implementation. The current study makes recommendations for improving the competitiveness of women SMEs in Jordan using an IT adoption model controlled by cloud SaaS. Since not all provinces possessed women SMEs, the total sample from all women SMEs in Jordan is 55 units as determined by the census sampling technique.

A comprehensive review on medicinal plants possessing antioxidant potential.

Many research studies have proposed that about two-thirds of the medicinal plant species of the world possess significant antioxidant potential. Antioxidants are very beneficial as they decrease oxidative stress (OS) in cells and hence play their role in management as well as treatment of numerous diseases like cancers, cardiovascular diseases, as well as many inflammatory illnesses. This review comprises the antioxidant potential of numerous parts of medicinal plants like leaves, stems, roots, seeds, fruits, as well as bark. Synthetic antioxidants named butylated hydroxyanisole (BHA) as well as butylated hydroxytoluene (BHT) are extensively employed in foods because of their role as food preservatives. Several natural antioxidants have better efficacy as compared to synthetic antioxidants. These medicinal plants include Geranium sanguineum L., Rheum ribes L., Diospyros abyssinica, Sargentodoxa cuneata Rehd. Et Wils, Pistacia lentiscus, Ficus microcarpa L. fil., Polyalthia cerasoides (Roxb.) Bedd, Cunn, Teucrium polium L., Crataeva nurvala Buch-Ham., Urtica dioica L., Dracocephalum moldavica L., Momordica Charantia L., Acacia auriculiformis A., Bidens pilosa Linn. The Lamiaceae species, Radiata, Leea indica, Pelargonium endlicherianum, Salvia officinalis L., and Uncaria tomentosa (Willd.) DC. The literature study disclosed more side effects of synthetic antioxidants (including food additives) in comparison with natural antioxidants and for prevention of many diseases.

Psychosocial Safety Climate in the Malaysian Context: A Systematic Literature Review

As a climate that represents organizational engagement, management commitment, organizational communication, and priority regarding employee psychological safety health, the psychosocial safety climate (PSC) is envisioned as existing in every firm. As a chose environment build for mental wellbeing inside the work environment, studies uncover that PSC is elucidated to numerous parts of mental wellbeing like burnout, depression, and anger. In Western literature, the topic of PSC has received more and more attention as a significant construct. However, in the Asian context, PSC has not been thoroughly examined before. This review's objective is to investigate PSC in the Malaysian context across various occupations. The reviewed articles were obtained from one main database, specifically Google Scholar. The search process made use of the keywords in the titles and abstracts, such as "psychosocial safety climate" and "psychosocial safety climate in Malaysia”. It resulted in 10 articles that satisfied the requirements. This review identified the main factors as work engagement, emotional demands, emotional exhaustion, job performance, job resources, counterproductive work behavior and job content. Numerous studies on PSC are needed in the future to expand its influence on work and health outcomes. The evidence currently available is limited.

КОВЗАННЯ ЧАСТИНКИ ПО РУХОМІЙ ГОРИЗОНТАЛЬНІЙ ПЛОЩИНІ

A lot of engineering problems relate to the interaction of working bodies of machines with particles of technological material and require analytical dependencies of particle movement on a moving rough plane. When a particle hits a moving horizontal rough plane, which remains horizontal during movement, the particle begins to slide along it. The character of the movement of the plane determines the shape of the particle's sliding trajectories. The reciprocating oscillations of the horizontal plane, as well as translational oscillations, when all points of the plane describe circles, are sufficiently researched. However, there is no rotation of the plane in these cases. However, numerous parts of machines and mechanisms carry out just such a movement. If the plane moves translationally, the particle moves along a trajectory, which is similar to the curve described by the plane. During the rotational movement of the plane, the particle moves along a spiral of the correct shape. In the case of a combination of these two movements, at the initial stage the relative motion of the particle is chaotic, but over time it acquires the shape of a spiral regardless of point of particle incidence to the plane. The article deals with the relative motion of a particle on a horizontal rough plane, which carries out complex oscillations, which are the result of moving a point of the plane in a circle with a constant angular velocity relative to its center and simultaneous rotation of the plane around this point with the same angular velocity in the opposite direction. The partial case of oscillations, when the lengths of the crank and slider are equal to zero, is considered. Analytical dependencies of particle motion were found by methods of differential geometry. The obtained regularities make it possible to significantly expand the theory of particle movement on the surface. In addition, they can be applied to the geometric design of mechanisms of the crank-slider type, in which the length of the slider is equal to the length of the crank. Key words: relative motion, horizontal plane, oscillations with rotational motion, particle, differential equations.

Dynamic and electrical damping of deep spherical sandwich shells with electrorheological fluid core and FG-GPLRC skins

This paper focuses on the vibration and damping of a deep spherical sandwich shell with a new composition. The shell is made with a core of electrorheological (ER) fluid and skins made of a nanocomposite material with graphene platelets (GPL) to make them stronger. The displacement field is governed by first-order sandwich theory. The properties of the skins, ER fluid, and sealants are dependent on the position, applied electric field, and frequency, respectively. Combining the strain-displacement relation based on the deep shells and linear constitutive laws based on the Hooke and Kelvin-Voigt theories provides the governing motion equations of this structure. The highly coupled differential equations are solved by a semi-analytical solution. The analytical portion is a trigonometric expansion (TE) technique that solves the equations along the circumferential direction. The generalized differential quadrature (GDQ) method is employed as the numerical part to solve the remaining equations along the meridional path. After performing the convergence and verification studies, the frequencies and loss factors correlated to the first ten vibrational angular modes under the effect of various parameters are analyzed.

Forecasting of hygrothermal behaviour of direct solar floors using artificial neural networks

Due to the wide range of factors that influence the performance of the direct solar floor (DSF) hygrothermal behaviour, the dynamic simulation using physical models is a difficult task. The DSF thermal simulation are tied to a number of variables that can occasionally be beyond of our control. In this study the hygrothermal behaviour of an experimental room heated by a DSF is predicted using a long short-term memory (LSTM) and a Convolutional Neural Network (CNN) models. First, we studied the DSF system performance in a Mediterranean climate experimentally, and used the results to validate the numerical part. Then, the proposed LSTM and CNN neural network methods are explored to forecast the temperature and humidity of indoor air. The developed model was trained and tested using real experimental data. The predictive accuracy of the proposed models was compared with other models such as the linear switching model (PWARX) and TRNSYS tools, and evaluated using various statistical assesment metrics. The statistical indicators demonstrate that the LSTM outperforms the CNN, PWARX and TRNSYS model’s in terms of forecasting accuracy.

Bio-actives from Caesalpinia sappan L.: Recent advancements in phytochemistry and pharmacology

• C. sappan is well known for its various industrial applications. • Newly isolated compounds from C. sappan consist of diterpene, homoisoflavones, and phenolics. • Bioactive compounds from C. Sappan exhibit various bioactivities. • C. sappan bioactive compounds also provide organ protection effect. • Toxicity of C. sappan extract should be considered while formulating herbal medicine. Caesalpinia sappan Linn. or Sappanwood is a redwood, full-fledged in numerous parts of Southeast Asia and well known for its red pigments, dye, food additive, and several medicinal properties. Many active chemical compounds in sappanwood extract have been identified and evaluated for medicinal properties such as anticancer, antimicrobial, anti-inflammatory, anti-arthritic, neuroprotective effect, also protective effect on organs like heart, kidney, liver, and intestine. Additional attempts are underway to isolate novel phytochemicals and to evaluate their possible bioactivities . The present review reported the newly isolated and identified phytochemicals from C. sappan including diterpenes (cassane derivatives), homoisoflavones (sappanol and protosappanins derivatives) and phenolics (epicaesalpin J and dracaenone derivatives). Pharmacokinetics of major bioactive compounds in C. sappan has been revisited. The recently investigated biological activities (pharmacodynamics) of various bioactive compounds from C. sappan has been a brief discussion . Additionally, the protective effect of various bioactive compounds on different organs including the kidney, liver, heart, and gastrointestinal tract have been scrutinized. Moreover, the toxicological effect of the significant active molecules in C. sappan has been outlined. Finally, the challenges and hurdles for herbal medicine development have been discussed.

Sustainable Urban Conveyance Selection through MCGDM Using a New Ranking on Generalized Interval Type-2 Trapezoidal Fuzzy Number

This article proposes a modified ranking technique for generalized interval type-2 trapezoidal fuzzy numbers. For demonstrating uncertainty and managing imprecision in decision-making information, interval type-2 fuzzy sets are beneficial. The proposed ranking methodology resolves the difficulty of multi-criteria group decision-making on sustainable urban conveyance. Additionally, the proposed ranking approach considers all crucial aspects of transportation sustainability, including the effectiveness of durable transportation systems from economic, social, and ecological perspectives in multi-criteria group decision-making scenarios. The new ranking methodology yields superior outcomes for choosing sustainable urban transportation options. In the numerical part, studies compared the proposed ranking approach to other methods currently used for various MCDM techniques.

Perceived Popularity of TikTok among Gen-Z

With web-based media, there developed huge open doors for individuals to develop their thoughts, interests, business, brands, or just themselves. Different applications cleared the way; however, just a couple of them were acknowledged by the crowd to endure and remain in the evolving scene. In such a domain, video content utilization and creation kept developing and growing with included highlights and channels, which brought forth the short-structure video creation application TikTok in 2016, hailing from Beijing. TikTok is a free short video-making application that is accessible on both AppStore and Google Play. It is difficult to look here and there to watch different recordings, remake, download, and share, make duets, and utilize various channels and sounds. The application broke the web due to its intriguing outcomes through the least endeavors. Fifteen seconds of name, fame, and achievement – TikTok is the main objective for short-structure versatile video. It is principally famous in pre-adolescents and teenagers; numerous youths are getting well known; however, at this stage. There are numerous major parts in the video stage like YouTube, Facebook, Instagram, Snapchat, etc. TikTok has its clients in millions everywhere over the world, including India. TikTok turned into another subculture that is arbitrary, chaotic, and addictive for the teenagers of the world. The application was a significant hit for Gen Z, as it involved the greater part of the dynamic clients and substance makers. TikTok optimizes content based on user-centric theory, user experience theory, UGC, and suggested algorithms, increasing consumer loyalty towards the app. This paper centers on building up and understanding the purpose for the enormous fame and development of Gen Z’s application as of late through a research paper.

Supply Chain Modelling of the Automobile Multi-Stage Production Considering Circular Economy by Waste Management Using Recycling and Reworking Operations

The supply chain management plays a crucial role in delivering products from a supplier, through the manufacturer, distributors, and retailers to the targeted customers. The lifecycle of the products can be ended at any stage due to imperfect quality or waste, which are typically not managed well for a good price. This product’s life can be extended and increased with the use of the circular economy for the value addition processes which turn the waste into byproducts, which can be sold with maximum profit. The automobile industry is associated with various other small industries and is very significant for the economy at the local, national, and international levels. However, the industry also requires sustainable development in its supply chain management, gained by introducing the circular economy concept to manage and reduce the generated waste. The consumption of carbon fiber-reinforced composites (CFRCs) in the manufacturing of numerous automotive parts has acquired immense attention this decade, but the process also generates imperfect products (waste). The proposed model is based on a mathematical formulation to manage imperfect production by reworking and recycling, where the former is required to re-add value to the proportion of the rejected parts, and the latter is to recycle the remaining scrap into useful products by using a circular economy. The outsourcing operation is also added to provide an optimal level of inventory and lot sizing for minimizing the total cost of the supply chain management. Data from the automobile part industry are tested to provide the practical implications of the proposed SCM mathematical model. Sensitivity analysis is performed to understand the significance level of the individual parameters affecting the objective function, i.e., the total cost of the SCM. The results show a meaningful insight for the managers to obtain the benefits of the circular economy in multi-stage automobile part production for sustainable and resilient supply chain management.