Engineering and Applied Science Letters (EASL)

Out of the top ten current global issues, climate change and pollution top the list. These issues have brought about adverse effects on our climate, health and communities. This study aims to investigate the structural performance of sawdust ash blended steel slag aggregate concrete and modelling their structural properties using a multivariate interpolation method. In order to achieve this, the physical properties, physio-chemical, chemical composition, mechanical properties tests were conducted. The result revealed that sawdust ash is classified as a class C type pozzolan having a total of 61.59% combined percentage masses of silica, alumina and ferric oxides, while steel slag aggregate is classified as poorly graded. The composite concrete recorded higher density, compressive and split tensile strengths when compared with normal concrete cured in potable water. The results revealed that normal concrete with normal aggregate is more durable than sawdust ash blended steel slag aggregate (composite) concrete when cured in an aggressive environment. The developed models were found to agree strongly with the experimental data, with an outstanding correlation level. This research has led to the creation of high strength pozzolan blended steel slag aggregate concrete, thus improving waste management, reduction in environmental pollution and \(CO_2\) gas emission.

Collocation methods are efficient approximate methods developed by utilizing suitable set of functions known as trial or basis functions. These methods are used for solving differential equations, integral equations and integro-differential equations, etc. In this study, the Laguerre polynomial of degree 10 is used as a basis function to propose a collocation method for solving higher order linear ordinary differential equations. Four examples on \(4th\), \(6th\), \(8th\) and \(10th\) order ordinary differential equations are selected to illustrate the effectiveness of the method. The numerical results show that the proposed collocation method is easy and straightforward to implement, nevertheless, it is very accurate.

In this paper, a new forms of extended hypergeometric functions are introduced. Some functional relations, integral representations and transformation formulas for these functions are derived.

In this work, we numerically study a dynamic frictional contact problem between a thermo-piezoelectric body and a conductive foundation. The linear thermo-electro-elastic constitutive law is employed to model the thermo-piezoelectric material. The contact is modelled by the Signorini condition and the friction by the Coulomb law. A frictional heat generation and heat transfer across the contact surface are assumed. The heat exchange coefficient is assumed to depend on contact pressure. Hybrid formulation is introduced, it is a coupled system for the displacement field, the electric potential, the temperature and two Lagrange multipliers. The discrete scheme of the coupled system is introduced based on a finite element method to approximate the spatial variable and an Euler scheme to discretize the time derivate. The thermo-mechanical contact is treated by using an augmented Lagrangian approach. A solution algorithm is discussed and implemented. Numerical simulation results are reported, illustrating the mechanical behavior related to the contact condition.

This paper presents the variation of radiofrequencies intensities from the DTTV-transmitter in Kampala Metropolitan for the sub 700 MHz (470-694 MHz) and the 700 MHz (694-790 MHz) frequency bands. The results of this study showed that though all the measurement locations from the transmitter have a good reception of DTTV signals, their radiofrequency intensities varied at the different points on the same measurement location at a constant distance from the DTTV transmitter. The study further showed that there is a general decrease in the radiofrequency intensities for the sub 700 MHz frequency band and a slight general increase in the radiofrequency intensities for the 700 MHz frequency band. This research revealed that the measured Reference Signal Received Power (RSRP) values for all the measurement locations where within the IEEE and FCC recommended values for any DTTV signal reception.

In this paper, we establish some new Čebyšev type inequalities for functions whose modulus of the mixed derivatives are co-ordinated quasi-convex and \(\alpha\)-quasi-convex and \(s\)-quasi-convex functions.

In this study, a mathematical model of dual latency compartments is developed to investigate the transmission dynamics of COVID-19 epidemic in Oyo state, Nigeria. The model consists of non-pharmaceutical control strategies which include the use of face masks, social-distancing and impact of mass-media on the spread of novel coronavirus in the state. Results indicate control reproduction number \(R_C = 1.4\) with possibilities of high constructive influence of mass-media. Thus, at the fitted values of \(\sigma _f = 0.1,\; \sigma _d = 0.1,\;\sigma _m = 0.6\), the peak of the COVID-19 epidemic is attained after 59,217 infectious quarantined individuals and 328,440 infectious but not quarantined individuals have contracted COVID-19 in about 439 and 443 days respectively from the date of the first incidence. Therefore, efforts on mass-media with programs that can inform the people on effective use of face masks, social-distancing and other safety measures can aid reduction of reproduction number to a value below 1 necessary for eradication of the disease.

In this paper, we introduce the notion of modified Suzuki-Edelstein-Geraghty proximal contraction and prove the existence and uniqueness of best proximity point for such mappings. Our results extend and unify many existing results in the literature. We draw corollaries and give illustrative example to demonstrate the validity of our result.

Novel coronavirus likewise called COVID-19 began in Wuhan, China in December 2019 and has now outspread over the world. Around 63 millions of people currently got influenced by novel coronavirus and it causes around 1,500,000 deaths. There are just about 600,000 individuals contaminated by COVID-19 in Bangladesh too. As it is an exceptionally new pandemic infection, its diagnosis is challenging for the medical community. In regular cases, it is hard for lower incoming countries to test cases easily. RT-PCR test is the most generally utilized analysis framework for COVID-19 patient detection. However, by utilizing X-ray image based programmed recognition can diminish the expense and testing time. So according to handling this test, it is important to program and effective recognition to forestall transmission to others. In this paper, author attempts to distinguish COVID-19 patients by chest X-ray images. Author executes various pre-trained deep learning models on the dataset such as Base-CNN, ResNet-50, DenseNet-121 and EfficientNet-B4. All the outcomes are compared to determine a suitable model for COVID-19 detection using chest X-ray images. Author also evaluates the results by AUC, where EfficientNet-B4 has 0.997 AUC, ResNet-50 has 0.967 AUC, DenseNet-121 has 0.874 AUC and the Base-CNN model has 0.762 AUC individually. The EfficientNet-B4 has achieved 98.86% accuracy.

Our purpose in this paper is to use \(\psi-\)Riemann-Liouville fractional integral operator which is the fractional integral of any function with respect to another increasing function to establish some new fractional integral inequalities of Hermite-Hadamard, involving concave functions. Using the concave functions, we establish some new fractional integral
inequalities related to the Hermite-Hadamard type inequalities via \(\psi-\)Riemann-Liouville fractional integral operator.