Terms Of Integrals Research Articles

Barycentric Interpolation Collocation Method for Solving Fractional Linear Fredholm-Volterra Integro-Differential Equation

In this article, barycentric interpolation collocation method (BICM) is presented to solve the fractional linear Fredholm-Volterra integro-differential equation (FVIDE). Firstly, the fractional order term of equation is transformed into the Riemann integral with Caputo definition, and this integral term is approximated by the Gauss quadrature formula. Secondly, the barycentric interpolation basis function is used to approximate the unknown function, and the matrix equation of BICM is obtained. Finally, several numerical examples are given to solve one-dimensional differential equation.

Numerical investigation of generalized tempered-type integrodifferential equations with respect to another function

This paper studies two efficient numerical methods for the generalized tempered integrodifferential equation with respect to another function. The proposed methods approximate the unknown solution through two phases. First, the backward Euler (BE) method and first-order interpolation quadrature rule are adopted to approximate the temporal derivative and generalized tempered integral term to construct a semi-discrete BE scheme. Second, the backward differentiation formula (BDF) and second-order interpolation quadrature rule are adopted to establish a semi-discrete second-order BDF (BDF2) scheme. Additionally, the stability and convergence of two semi-discrete methods are deduced in detail. To further demonstrate the effectiveness of proposed techniques, fully discrete BE and BDF2 finite difference schemes are formulated. Subsequently, the theoretical results of two fully discrete difference schemes are presented. Finally, the numerical results demonstrate the accuracy and competitiveness of the theoretical analysis.

Intelligent solution for automatic online exam monitoring

<p><span lang="EN-US">E-learning has shown significant growth in recent years due to its unavoidable benefits in unexpected situations such as the coronavirus disease 2019 (COVID-19) pandemic. Indeed, online exam is a very important component of an online learning program. It allows higher education institutions to assess student learning outcomes. However, cheating in exams is a widespread phenomenon worldwide, which creates several challenges in terms of integrity, reliability and security of online examinations. In this study, we propose a continuous authentication system for online exam. Our intelligent inference system based on machine learning algorithms and rules, detects continuously any inappropriate behavior in order to limit and prevent fraud. The proposed model includes several modules to enhance security, namely the registration module, the continuous students’ identity verification and control module, the live video stream and the end-to-end sessions recording.</span></p>

Dynamics of Chains of Many Oscillators with Unidirectional and Bidirectional Delay Coupling

Chains of Van der Pol equations with a large delay in coupling are considered. It is assumed that the number of chain elements is also sufficiently large. In a natural manner, a chain is replaced by a Van der Pol equation with an integral term in the space variable and with periodic boundary conditions. Primary attention is given to the local dynamics of chains with unidirectional and bidirectional coupling. For sufficiently large values of the delay parameter, parameters are explicitly determined for which critical cases occur in the stability problem for the zero equilibrium state. It is shown that the problems under consideration have an infinite-dimensional critical case. The well-known methods of invariant integral manifolds and the methods of normal forms are inapplicable in these problems. Proposed by this paper’s author, the method of infinite normalization—the method of quasi-normal forms—is used to show that the leading terms of the asymptotics of the original system are determined by solutions of (nonlocal) quasi-normal forms, i.e., special nonlinear boundary value problems of the parabolic type. As the main results, corresponding quasi-normal forms are constructed for the considered chains.

Analytical solutions of the generalized Kaup–Newell equation

The generalized Kaup–Newell equation for describing the pulse propagation in a nonlinear optical medium is considered. The traveling wave reduction of this equation is taken into account. The method of direct transformations is used to construct a general solution of a nonlinear ordinary differential equation. Analytical solutions are found, expressed in terms of elliptic integrals in canonical form. The implicit function method is applied to find some degenerate solutions under constraints on the model parameters. Among the solutions obtained there are doubly periodic solutions on the complex plane, as well as optical solitons.

Teachers’ Self-Efficacy and Attitudes towards the Use of Information Technology in Classrooms

This research aims to measure the level of integration of ICT in teaching, learning, and assessment practices during the COVID-19 pandemic. We propose measuring teachers’ attitude, self-efficacy, and skills in using technology because the quality of education during the pandemic was influenced by these factors. An online questionnaire was distributed amongst 189 teachers from all levels of education, from kindergarten to high school, and the sample was described using the means, distribution, and number of years of experience in education. The statistical analyses employed for the quantitative data included correlational study and mediation analysis. We found a correlation between gender, environment, barrier level and teachers’ attitude, self-efficacy, and skills. Also, the teachers’ attitude mediates the association between ICT skills and ICT integration in the educational process. The results reveal high positive scores in terms of ICT integration in teaching practices, teachers’ attitude, self-efficacy, and ICT skills. The novelty of this research is that this is the first time a questionnaire based on attitude, self-efficacy, ICT skills, and ICT integration in the classroom has been applied in the northern Moldavian region of Romania, and the results underline the educational implications for in-service teacher training.

Generalized Lyapunov Functions for Discrete-Time Lurie Systems With Slope-Restricted Nonlinearities

A class of Lyapunov functions for discrete-time Lurie systems with monotonic non-linearities is proposed. The Lyapunov functions are composed of quadratic terms on the states and of the system's non-linearities as well as Lurie-Postnikov type integral terms. Crucially, positive definiteness of the matrix in the generalised quadratic form and positivity of the scaling terms of the Lurie-Postnikov integrals are relaxed in the stability conditions. Furthermore, they are used for regional stability analysis and performance assessment. Numerical examples show that the proposed Lyapunov function structure matches or outperforms existing ones for these systems.

The impact of PEEK pretreatment using H2SO4, riboflavin, and aluminum trioxide on the extrusion bond strength to canal dentin luted with Polymethyl methacrylate and resin-based composite cement.

To evaluate the effects of various surface pretreatment methods, including H2SO4, Riboflavin, and Al2O3, as well as different luting cement types, namely Methyl Methacrylate based Cement (MMBC) and composite-based cement (CBC), on the extrusion bond strength (EBS) of poly-ether-ether-ketone (PEEK) posts bonded to canal dentin. This study involved 120 single-rooted human premolar teeth that underwent endodontic treatment. Following root canal preparation, PEEK posts were fabricated from PEEK blanks using a CAD-CAM system, resulting in a total of 120 posts. The posts were randomly assigned to one of four groups based on their post-surface conditioning: Group A H2SO4, Group B RF, Group C Al2O3, and Group D (NC), each consisting of 30 posts. Within each group, there were two subgroups based on the type of luting cement used for bonding. Subgroups A1, B1, C1, and D1 (n=15 each) utilized CBC, while Subgroups A2, B2, C2, and D2 (n=15 each) used MMBC.The bond strength between the PEEK posts and root dentin was assessed using a universal testing machine, and the failure modes were examined under a stereomicroscope. Statistical analysis, including one-way analysis of variance (ANOVA) and Tukey's Post Hoc test with a significance level of p=0.05, was performed to analyze the data and evaluate the effects of surface treatment and luting cement type on the bond strength. Group B2, which underwent RF conditioning followed by Super-Bond C&B cement application, exhibited the highest bond strength scores at the coronal section (9.57±0.67 MPa). On the other hand, Group D1, which had no conditioning (NC) and used Panavia® V5 cement, showed the lowest EBS at the apical third (2.39±0.72 MPa). The overall results indicate that the different conditioning regimens and luting cement types did not significantly influence the bond strength of PEEK posts to root dentin (p>0.05). Riboflavin activated by photodynamic therapy (PDT) and H2SO4 can be effective surface conditioners for PEEK posts. These treatments have shown potential for enhancing the bond strength between PEEK and resin cement. Additionally, the study revealed that MMA-based cement outperformed composite-based cement in terms of bond integrity with PEEK posts.

Assessment of CATHARE code against DEC-A upper head SBLOCA experiments

Design Extension Conditions (DEC)-A assessments of the operating nuclear power plants are generally considered for the purpose of getting additional safety demonstrations of their capability to undergo conditions that are generally more severe than DBAs by features implemented in the design and accident management measures. The pursued methodology is generally based upon Best Estimate approaches aiming at verifying that the safety limits in terms of integrity of the barriers against eventual large or early releases of radioactive material are fulfilled. These aspects are nowadays being experimentally and analytically addressed within the OECD/NEA experimental projects like the ATLAS and PKL series where a set of DEC-A experiments are considered. In this paper, experiments related to SBLOCA at the vessel upper head of the pressurized vessel of ATLAS and PKL are analytically assessed using the CATHARE code. These experiments includes issues related to common cause failure of the safety injection system and operator actions for preventing core excessive overheating. It is shown that, on the one hand, the safety features embedded in the design together with the operator actions are capable to prevent the progression towards a severe accident state and on the other hand, the code prediction capabilities for such scenario are generally good but still to be enhanced.

Improved active disturbance rejection speed control for autonomous driving of high-speed train based on feedforward compensation.

Due to the complex and changeable train operation environment and the unstable and time-varying parameters, accurate modeling is limited. Therefore, a modified active disturbance rejection control algorithm based on feedforward compensation (FC-MADRC) is proposed targeting the speed control problem of trains under the circumstances of external disturbances, which reduces the dependence on the train model. Firstly, the state space equation is established based on the single-particle mathematical model of the train, and all the running resistances are regarded as disturbances. Secondly, the FC-MADRC algorithm is designed. Based on the terminal attractor function and the novel Sigmoid function, an improved tracking differentiator (ITD) is designed. An improved fal (nsfal) function with better smoothness is constructed by using the properties of the Dirac δ function, and an ameliorative nonlinear state error feedback (ANLSEF) and a modified extended state observer (IESO) are designed based on the nsfal function. Furthermore, based on the thought of PID, the integral term of error is introduced into ANLSEF for the nonlinear operation to reduce the steady-state error of train speed tracking. In order to promote the robustness and control accuracy of the system, the feedforward compensation term and disturbance compensation term are combined to perform dynamic compensation for disturbances in real time. Finally, the simulation is carried out with CRH380A train data. The results indicate that compared with conventional ADRC and 2DOF-PID, FC-MADRC has the more vital anti-disturbance ability and higher tracking accuracy. FC-MADRC has the advantages of solid anti-disturbance, fast response, and high tracking accuracy. Under the premise of external disturbance, it can still achieve accurate speed tracking under different road conditions.

Sustainable Development of Character Education in Physical Education: Bibliometric Analysis Using VOSviewer

Objective: This study uses a bibliometric approach and the VOSviewer program to assess the growth of research papers on incorporating character education into physical education so that other researchers can get information and develop it. For theme study next still in scope education character through education physica.
 
 Method: Reference sample article totaling 999 articles with using the Publish or Perish application sourced from the Google Scholar database. The title and abstract of the article serve as guidelines in carrying out the process of searching for the keywords character education and physical education.
 
 Results: The data search found 99 9 relevant articles published in 2012 to 2022. This study used 3 keywords, namely: integration, character education, and physical education. The term character education has 141 links, and a total of 459 strengths. The term physical education has 220 links, and a total of 950 strengths. And the integration term has 264 links, and a total of 2,919 strengths.
 
 Conclusion: The development of the number of publications that integrate character education into physical education over the last 11 years has experienced fluctuations, namely in 2012-2015 it has increased. From 2012 there were 98 publications, to 113 publications in 2013, 108 publications in 2014, and 120 publications in 2015. Before finally experiencing a decline in publications in 2016-2022 (sequentially 111, 103, 115, 93, 72, 33, 33 publications annually). So that the research opportunities for character education in physical education are still very likely to be researched and associated with other terms.

Design of integral sliding mode control and fuzzy adaptive PI control for voltage stability in DC microgrid

This paper introduces a novel control strategy that merges integral sliding mode control with fuzzy adaptive PI control. This hybrid approach maximizes the benefits of both techniques to ensure voltage stability in DC microgrid. Firstly, a mathematical model characterizes the DC–DC boost converter. Subsequently, a sliding surface, incorporating an integral term, is employed to regulate the converter’s output voltage and current errors. To address uncertainties stemming from factors like input inductance and output capacitance, a dynamic sliding mode controller is formulated. The proposed sliding mode control scheme significantly reduces the time required for voltage stability, curbs system oscillations, and showcases robustness. Furthermore, the inclusion of fuzzy adaptive PI control aids in refining the voltage deviation signal and droop resistance. This enhancement improves the precision of the error tracking system. Finally, the effectiveness of this strategy is demonstrated through MATLAB simulations, supported by experimental validation and analysis. The findings reveal that this control strategy efficiently accelerates the convergence of DC microgrid voltage to a stable state.

Перспективы нового уровня дву- и многосторонних отношений стран центрально- азиатского пространства

В работе рассмотрены проблемы и перспективы развития Нового Казахстана в условиях глобальных вызовов и рисков современности. В этом ключе важно обеспечение безопасности и стабилизации национальных экономик стран Центральной Азии для укрепления многостороннего сотрудничества и взаимодействия, особенно в части кооперации и интеграции, возобновления связей в сферах торговли, науки, транспорта и логистики, образования и культуры. Представлена экспертная оценка возможностей и путей развития нашей страны. Представлены основные направления сотрудничества и взаимодействия республики с основными партнерами в центрально-азиатском пространстве и международными группировками и союзами.

COMPETITIVENESS INDEX OF PENINSULAR MALAYSIA'S NORTHERN BORDER DISTRICTS

Competitive cities are known for their substantial economic growth, high incomes, and the ability to attract foreign investments. While a strong economy is crucial, other factors such as effective governance, efficient transportation, adequate housing, social inclusivity, and environmental sustainability also contribute to a city's competitiveness. This paper aims to assess the economic competitiveness of border districts in northern Peninsular Malaysia. Border cities hold significant importance following their proximity to neighbouring countries, subsequently offering advantages in terms of trade opportunities, cultural exchange, diplomatic relations, security, and socio-cultural integration. This research employed the quantitative method to measure the competitiveness level of 10 districts using economic and socioeconomic statistical data from the Department of Statistics Malaysia. The results indicated a distinct disparity among the districts along the Malaysia-Thailand border. In particular, the western districts of Perlis and Kubang Pasu displayed a higher level of economic development compared to the rural eastern districts due to their economic diversity and close proximity to industrial hubs such as Penang, Sungai Petani, and Songkhla in Southern Thailand. Furthermore, the strategic locations of the busiest international entry points, Bukit Kayu Hitam and Padang Besar, contribute significantly to the importance of logistics in these areas. In contrast, the middle and eastern districts heavily rely on agricultural activities, resulting in lower average incomes and higher poverty rates.

Численное решение двумерной задачи определения скорости распространения сейсмических волн в неоднородных cредах с памятью

The numerical method for two-dimensional inverse dynamic seismic problem for a viscoelastic isotropic medium is presented. The system of differential equations of elasticity for isotropic medium of memory type is considered as a mathematical model. The unknown values are the displacement, the memory function of the medium (the kernel of the integral term) and the propagation velocity of elastic waves in a weakly horizontally inhomogeneous medium. Additional information for the inverse problem is the response displacement measured on the surface. The method is based on reducing the inverse problem to a system of Volterra-type integral equations and their sequential numerical implementation. The results of the study are analyzed and compared with the analytical solution. It is shown that the results are in satisfactory agreement.

Legal support for an environmentally balanced system of natural resource management in terms of European integration of Ukraine

Legal support for an environmentally balanced system of natural resource management in terms of European integration of Ukraine

A decentralized public-permissioned blockchain framework for enhanced security of health records in fog computing

Medical health records comprise sensitive patient data for precise diagnosis and successive treatment. However, it must be stored and shared securely to protect data privacy. Generally, health records are kept on centralized servers, which raise the risk of security breaches and involve trust in a single authority that cannot efficiently defend data from internal attacks. Blockchain (BC) is extensively used in medical health records management because of its decentralized and tamper-proof properties. This work introduces a public-permissioned BC technology with a decentralized ledger (DL) to manage medical health records in the fog computing layer. The considered BC is decentralized and allows the transmission of records within the decentralized network of records. The data blocks are hashed using the SHA-256 hash algorithm. Especially, an Adaptive RSA Digital Signature Algorithm (ARSA-DS) is developed to prevent data tampering with medical health records in the fog computing layer. Moreover, an Ebola Search Optimization based Key Selection (ESO-KS) technique is employed to find the ideal key from the randomly generated keys to reduce processing time and increase overall efficiency. The proposed decentralized BC framework will help to preserve patient privacy and prevent the tampering of health records by attacks; moreover, it is efficient in terms of confidentiality, integrity, and availability.

Консолидация информационных моделей объектов строительства в единое пространство больших данных

The article discusses the issues of consolidation and integration of the accumulated arrays of capital construction models information of objects into a common space of information models, created according to the organization and processing of big data arrays principles. The problems of geoinformation binding of information models, organization of means and places of their storage, methods of processing and providing access to interested subjects are considered. It is proposed to create a common space of information models according to a distributed decentralized scheme with direct interaction between state and commercial participants, both in terms of business integration, and in terms of joint data management and implementation of replication technologies. Examples of practical application of integrative solutions of a common information space of open data from information models of construction objects in relation to existing information systems and services are given.

Supplementation of Thymoquinone Nanoparticles to Semen Extender Boosts Cryotolerance and Fertilizing Ability of Buffalo Bull Spermatozoa.

Thymoquinone nanoparticles (TQNPs) are broadly utilized in numerous pharmaceutical applications. In the present study, we tested the effects of TQNP supplementation on sperm quality and kinematics, acrosome exocytosis, oxidative biomarkers, apoptosis-like and morphological changes of frozen-thawed buffalo sperm, as well as the fertilizing capacity. Semen was collected from buffalo bulls, diluted (1:10; semen/extender), and divided into five aliquots comprising various concentrations of TQNP 0 (CON), 12.5 (TQNP12.5), 25 (TQNP25), 37.5 (TQNP37.5), and 50 (TQNP50) µg/mL, and then cryopreserved and stored in liquid nitrogen (-196 °C). The results revealed that TQNPs (25 to 50 µg/mL) provided the most optimal results in terms of membrane integrity (p < 0.001) and progressive motility (p < 0.01). In contrast, TQNP50 resulted in a greater post-thawed sperm viability (p = 0.02) compared with other groups. The addition of TQNPs to the extender had no discernible effects on sperm morphology measures. Sperm kinematic motion was significantly improved in the TQNP50 group compared to the control group (p < 0.01). TQNPs effectively reduced the content of H2O2 and MDA levels and improved the total antioxidant capacity of post-thawed extended semen (p < 0.01). The addition of TQNP significantly increased the number of intact acrosomes (p < 0.0001) and decreased the number of exocytosed acrosomes (p < 0.0001). A significant reduction in apoptosis-like changes was observed in TQNP groups. The non-return rates of buffalo cows inseminated with TQNP50-treated spermatozoa were higher than those in the control group (p < 0.05; 88% vs. 72%). These findings suggested that the freezing extender supplemented with TQNPs could effectively enhance the cryotolerance and fertility of buffalo sperm.

3D Heterogeneous Database for Structural Analysis of Historic Buildings. A Discussion on Process Pipelines

This paper presents a methodology for creating a comprehensive heterogeneous 3D database for the structural evaluation of a historic building by using both non-destructive and destructive surveys combined with historical information. The availability of adequate data on the actual conditions is crucial when assessing the seismic vulnerability and structural behavior of a historic building and validating the results. A reliable 3D database must accept different kinds of data, e.g., the results of destructive/non-destructive surveys, historical information, etc. It must also be interrogated and enriched at any time. Therefore, creating such a 3D database may present several challenges in terms of data-gathering pipeline, comprehensiveness/redundancy, interpretation, organization, and integration with other heterogeneous data. The methodology we present in this paper includes 3D laser scanning, thermal imaging, and endoscopy combined with information regarding the state of conservation, construction history, materials, and techniques. We tested such methodology to create a database that was later used for Finite Element Modeling (FEM) to assess the seismic vulnerability of Diotti Palace, a neoclassical building that has been the seat of the Prefect of Milan since 1859. The results are analytically presented here. In conclusion, we highlight the pros and cons of the proposed methodology by means of a comparative discussion with the state of the art about 3D documentation pipelines for historic buildings and sites.