Engineering and Applied Science Letters (EASL)

Most radio stations use frequency modulation (FM) to broadcast yet amplitude modulation (AM) ensures long distance modulation. The limitations of FM reception are the line of sight and the area of reception. These two parameters are much smaller in FM compared to AM which makes AM modulation have an added advantage over FM modulation. The results presented in this paper include; direct modulation at different bias currents and different transmission fiber lengths and the amplitude modulation using the Mach-Zehnder. The results show the possibility to transmit huge data at high speeds to over 100Gbps.

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.

In this paper, we introduce the concept of a new family of convex functions namely \(n\)-polynomial generalized convex functions of Raina type. We investigate the algebraic properties of a newly introduced idea and discuss their connections with convex functions. Furthermore, we establish the new version of Hermite–Hadamard and some refinements of Hermite-Hadamard type inequalities this class of functions. Finally, we investigate some applications to special means of real numbers. Results obtained in this paper can be viewed as a significant improvement of previously known results and also may stimulate and energize for further activities in this research area field.

Renewable energy systems (RESs) have an inherent quality of achieving independence Vis a Vis useful energy harnessing for self or localized use. At larger scale the renewable energy system allows the power generation and distribution without a significant harm to the environment. Propagation and proliferation of RESs and the Renewable Energy Technology (RET), collectively demand an effective policy making infrastructure to be in place to ensure their penetration locally and globally. Renewable Energy Policies have a great impact on how readily these systems are adopted by the investors and market, how efficient these systems are which is dependent on the research and development (R&D) of RESs, how effectively the country or region copes with the scourge of environmental harm with the use of RESs. Renewable Energy Policies also have an impact on how costly these technologies are and how these technologies fiscally benefit common man, investors and industries. Efficiency enhancement, stability and intelligent management of grids integrated with RES are also renewable policy dependent. This paper thoroughly and critically examines the importance of renewable energy policy. not just at domestic or national level but also at global level. It discusses in detail the core ingredients of renewable energy policy which were adopted in the past, which are being adopted now and which should be adopted in future. This paper also discusses policy, business and financial models; importance of tariff formulation, incentives and subsidies and a few factors which may pose a risk to the development and adoption of RESs. At the end a few suggestions have also been made which, if adopted, would help promote the RESs proliferation across the globe at a rapid pace and would ensure energy security, sustainable development and environmental conservation.

The number of songs are increasing at a very high rate around the globe. Out of the songs released every year, only the top few songs make it to the billboard hit charts .The lyrics of the songs place an important role in making them big hits combined with various other factors like loudness, liveness, speech ness, pop, etc. The artists are faced with the problem of finding the most desired topics to create song lyrics on. This problem is further amplified in selecting the most unique, catchy words which if added, could create more powerful lyrics for the songs. We propose a solution of finding the bag of unique evergreen words using the term frequency-inverse document frequency (TF-IDF) technique of natural language processing. The words from this bag of unique evergreen words could be added in the lyrics of the songs to create more powerful lyrics in the future.

The strategic value of the Navy’s submarine capabilities is greatly influenced by the ability of its supporting infrastructure to be able to maintain the confidentiality of submarine operations. Based on these conditions, this study aims to identify and analyze the operational readiness of submarines to increase the deterrence of the state defense system at sea. This study uses Interpretive Structural Modeling (ISM) and MIC-MAC diagrams. The ISM method is used to analyze the effect on the criteria. MICMAC diagrams are used as criteria for determining the related variables. Based on the results of the ISM and MICMAC diagram analysis, it was found that fifteen elements were divided into \(4\) (four) quadrants. Quadrant I (Autonomous) consists of six elements, such as \((C_1)\), \((C_2)\), \((C_3)\), \((C_4)\), \((C_{13)}\), \((C_{15})\). Quadrant II (Dependent) consists of six elements, such as \((C_5)\), \((C_6)\), \((C_7)\), \((C_{11})\), \((C_{12})\), \((C_{14})\). Quadrant IV (Independent) consists of three elements, such as \((C_8)\), \((C_9)\), \((C_{10})\). This research is expected to provide benefits to both academics and practitioners in the field of submarines and defense strategy.

The aim of this paper is to introduce strongest relation, cosets and middle cosets of anti \(Q\)-fuzzy subgroups of \(G\) with respect to \(t\)-conorm \(C.\) We investigate equivalent characterizations of them and we construct a new group induced by them, and give the homomorphism theorem between them.

We estimate the incubation period values and other forecasting predictors of SARS-CoV-2 for different countries located in different geographical locations of the earth and each one has a certain climate. The considered countries are the United States, Russia, the United Kingdom, Brazil, Spain, Bahrain, Egypt, Iran, Cyprus, India, France, and the Syrian Arab Republic. For estimating of the forecasting predictors values, we use the SEIR epidemic model and Runge-Kutta simulation method. The estimations are done up to the beginning of 2021 in aforementioned countries based on the collected data in these countries. We find that the incubation period values of SARS-CoV-2 are located between 2.5 days which returns to Bahrain and 10 days which returns to some countries in middle east. Also, we find that the average value of this period is about 6.5 days for the different location countries. Besides, we find that the average values of SARS-CoV-2 critical immunisation threshold, SARS-CoV-2 basic reproduction number and SARS-CoV-2 steady state population are 0.5, 2.3 and 0.5 respectively.

Although synthetic dyes are commonly used, natural dyes are still being utilized and used to improve their intrinsic aesthetic properties as the main material for the body’s beauty. For example, research results have shown that henna plant leaves comprise dye together with other additives. This provides a hint that if color from henna is properly studied, it can be used not only as body decoration but may also have fiber-substrates affinity. This paper explores the dyeing possibility-the ability to dye and the fastness qualities of henna dye extracted from henna leaves on cotton fabric compared to reactive dyeing using the same dyeing technique as reactive dyeing. Also, color fastness tests have been performed according to the ISO test methods. The implications of henna dye have been shown to have poor to moderate dyeing capability towards cotton fabrics as opposed to the reactive dyes when henna dyeing is accompanied by reactive dyeing. Similarly, henna dye demonstrated satisfactory properties of fastness as opposed to reactive dye. For henna dye with 50% shade, it gives an outstanding color tone with a good level of coloration. Taken into account the ability to dye and the fastness of color, the dyeing of matured henna leaves is equally advantageous to the dyeing of cotton fabrics.

The aim of this paper is to establish the Hermite-Hadamard-Fejér type inequalities for co-ordinated harmonically convex functions via Katugampola fractional integral. We provide Hermite-Hadamard-Fej\’er inequalities for harmonically convex functions via Katugampola fractional integral in one dimension.