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Demand and popularity of portable electronic devices are driving the designers to strive for higher speeds, long battery life and more reliable designs. Recently, an overwhelming interest has been seen in the problems of designing digital systems with low power at no performance penalty. Most of the very large-scale integration applications, such as digital signal processing, image processing, video processing and microprocessors, extensively use arithmetic operations. Binary addition is considered as the most crucial part of the arithmetic unit because all other arithmetic operations usually involve addition. Building low-power and high-performance adder cells are of great interest these days, and any modifications made to the full adder would affect the system as a whole. The full adder design has attracted many designer's attention in recent years, and its power reduction is one of the important apprehensions of the designers. This paper presents a 1-bit full adder by using as few as six transistors (6-Ts) per bit in its design. The paper aims to discuss these issues.

The outcome of the proposed adder architectural design is based on micro-architectural specification. This is a textual description, and adder's schematic can accurately predict the performance, power, propagation delay and area of the design. It is designed with a combination of multiplexing control input (MCIT) and Boolean identities. The proposed design features lower operating voltage, higher computing speed and lower energy consumption due to the efficient operation of 6-T adder cell. The design adopts MCIT technique effectively to alleviate the threshold voltage loss problem commonly encountered in pass transistor logic design.

The proposed adder circuit simulated results are used to verify the correctness and timing of each component. According to the design concepts, the simulated results are compared to the existing adders from the literature, and the significant improvements in the proposed adder are observed. Some of the drawbacks of the existing adder circuits from the literature are as follows: The Shannon theorem-based adder gives voltage swing restoration in sum circuit. Due to this problem, the Shannon circuit consumes high power and operates at low speed. The MUX-14T adder circuit is designed by using multiplexer concept which has a complex node in its design paradigm. The node drivability of input consumes high power to transmit the voltage level. The MCIT-7T adder circuit is designed by using MCIT technique, which consumes more power and leads to high power consumption in the circuit. The MUX-12T adder circuit is designed by MCIT technique. The carry circuit has buffering restoration unit, and its complement leads to high power dissipation and propagation delay.

The new 6-T full adder circuit overcomes the drawbacks of the adders from the literature and successfully reduces area, power dissipation and propagation delay.

This study aims to examine the reuse of plastic and fly ash (FA) to improve the soil and achieve sustainable development goals.

Sand from the Anzali port was reinforced with Geopet (GP) and stabilized with FA plus 3% sodium hydroxide. The GP was placed in FA-stabilized soil and the California bearing ratio (CBR), and unconfined compressive strength (UCS) tests were performed on samples at the optimum moisture content.

The results showed that the improvement in the optimum CBR was 174.9%. The UCS increased 15.25% and 48.65% in soil reinforced with three layers of GP plus 15% FA over those containing 10% and 5% FA, respectively. Additionally, the current analysis used response surface methodology (RSM) to investigate the impact of FA percentage, GP layers and their interaction on CBR. The results highlight the efficacy of the used RSM model, as evidenced by the significantly low p-value (<0.0001).

This demonstrates the suitability and effectiveness of RSM for evaluating CBR in this scientific study.

The purpose of this paper is to examine the flow, heat transfer and entropy generation characteristics for an inclined channel of two immiscible micropolar fluids.

The flow region consists of two zones, the flow of the heavier fluid taking place in the lower zone. The flow is assumed to be governed by Eringen’s micropolar fluid flow equation. The resulting governing equations are then solved using the homotopy analysis method.

The following findings are concluded: first, the entropy generation rate is more near the plates in both the zones as compared to that of the interface. This indicates that the friction due to surface on the fluids increases entropy generation rate. Second, the entropy generation rate is more near the plate in Zone I than that of Zone II. This may be due to the fact that the fluid in Zone I is more viscous. This indicates the more the viscosity of the fluid is, the more the entropy generation. Third, Bejan number is the maximum at the interface of the fluids. This indicates that the amount of exergy (available energy) is maximum and irreversibility is minimized at the interface between the fluids. Fourth, as micropolarity increases, entropy generation rate near the plates decreases and irreversibility decreases. This indicates an important industrial application for micropolar fluids to use them as a good lubricant.

The problem is original as no work has been reported on entropy generation in an inclined channel with two immiscible micropolar fluids.

The purpose of this paper is to propose the knowledge of thermal transport of magneto hydrodynamic non-Newtonian fluid flow over a melting sheet in the presence of exponential heat source.

The group of PDE is mutated as dimension free with the assistance of similarity transformations and these are highly nonlinear and coupled. The authors solved the coupled ODE’s with the help of fourth-order Runge–Kutta based shooting technique. The impact of dimensionless sundry parameters on three usual distributions of the flow was analyzed and bestowed graphically. Along with them friction factor, heat and mass transfer rates have been assessed and represented with the aid of table.

Results exhibited that all the flow fields (velocity, concentration and temperature) are decreasing functions of melting parameter. Also the presence of cross-diffusion highly affects the heat and mass transfer performance.

Present paper deals with the heat and mass transfer characteristics of magnetohydrodynamics flow of non-Newtonian fluids past a melting surface. The effect of exponential heat source is also considered. Moreover this is a new work in the field of heat transfer in non-Newtonian fluid flows.

The purpose of this paper is to investigate thermally and hydrodynamically fully developed convection in a duct of rectangular cross-section containing a porous medium and fluid layer.

The Darcy–Brinkman–Forchheimer flow model is adopted. A finite difference method of second-order accuracy with the Southwell-over-relaxation method is deployed to solve the non-dimensional momentum and energy conservation equations under physically robust boundary conditions.

It is found that the presence of porous structure and different immiscible fluids exert a significant impact on controlling the flow. Graphical results for the influence of the governing parameters i.e. Grashof number, Darcy number, porous media inertia parameter, Brinkman number and ratios of viscosities, thermal expansion and thermal conductivity parameters on the velocity and temperature fields are presented. The volumetric flow rate, skin friction and rate of heat transfer at the left and right walls of the duct are also provided in tabular form. The numerical solutions obtained are validated with the published study and excellent agreement is attained.

To the author’s best knowledge this study original in developing the numerical code using FORTRAN to assess the fluid properties for immiscible fluids. The study is relevant to geothermal energy systems, thermal insulation systems, resin flow modeling for liquid composite molding processes and hybrid solar collectors.

The purpose of this study is to find the thermo-hydraulic performances of compact heat exchangers (CHE’s), which are strongly depending upon the prediction of performance of various types of heat transfer surfaces such as offset strip fins, wavy fins, rectangular fins, triangular fins, triangular and rectangular perforated fins in terms of Colburn “j” and Fanning friction “f” factors.

Numerical methods play a major role for analysis of compact plate-fin heat exchangers, which are cost-effective and fast. This paper presents the on-going research and work carried out earlier for single-phase steady-state heat transfer and pressure drop analysis on CHE passages and fins. An analysis of a cross-flow plate-fin compact heat exchanger, accounting for the individual effects of two-dimensional longitudinal heat conduction through the exchanger wall, inlet fluid flow maldistribution and inlet temperature non-uniformity are carried out using a Finite Element Method (FEM).

The performance deterioration of high-efficiency cross-flow plate-fin compact heat exchangers have been reviewed with the combined effects of wall longitudinal heat conduction and inlet fluid flow/temperature non-uniformity using a dedicated FEM analysis. It is found that the performance deterioration is quite significant in some typical applications due to the effects of wall longitudinal heat conduction and inlet fluid flow non-uniformity on cross-flow plate-fin heat exchangers. A Computational Fluid Dynamics (CFD) program FLUENT has been used to predict the design data in terms of “j” and “f” factors for plate-fin heat exchanger fins. The suitable design data are generated using CFD analysis covering the laminar, transition and turbulent flow regimes for various types of fins.

The correlations for the friction factor “f” and Colburn factor “j” have been found to be good. The correlations can be used by the heat exchanger designers and can reduce the number of tests and modification of the prototype to a minimum for similar applications and types of fins.

The purpose of this paper is to study the effect of the addition of silicon carbide (SiC) microparticles and their contributions regarding the tensile and shear properties of the T800 fiber reinforced polymer composite at various fiber volume fractions. The tensile and shear properties of the hybrid composites where continuous T800 fibers are used as reinforcements in an epoxy matrix embedded with SiC microparticles have been studied.

The results were obtained by implementing a micromechanics approach assuming a uniform distribution of reinforcements and considering one unit cell from the whole array. Using the two-step homogenization process, the properties of the materials were determined by using the finite element analysis (FEA). The predicted elastic properties from FEA were compared with the analytical results. The analytical models were implemented in the MATLAB Software. The FEA was performed in ANSYS APDL.

The mechanical properties of the hybrid composite had increased when compared with the properties of the conventional FRP. The results suggest that SiC particles are a good reinforcement for enhancing the transverse and shear properties of the considered fiber reinforced epoxy composite. The microparticle embedment has significant effect on the transverse tensile properties as well as in-plane and out-of-plane shear properties.

This is significant because improving the properties of the composite materials using different methods is of high interest in the materials community. Using this study people can work on the process of including different type of microparticles in to their composite designs and improve their performance characteristics. The major influence of the particles can be seen only at lower volume fractions of the fiber in the composite. Only FEA and analytical methods were used for the study.

Material property improvements lead to more advanced designs for aerospace and defense structures, which allow for high performance under unpredictable conditions.

This type of study proves that the embedment of different microparticles is a method that can be used for improving the properties of the composite materials. The improvement of the transverse and shear properties will be useful especially in the design of shell structures in the different engineering applications.

The purpose of this study is to solve convective diffusion equation analytically by considering appropriate boundary conditions and using the Taylor-Aris method to determine the solute concentration, the effective and relative axial diffusivities.

>An analysis has been conducted on how body acceleration affects the dispersion of a solute in blood flow, which is known as a Bingham fluid, within an artery. To solve the system of differential equations analytically while validating the target boundary conditions, the blood velocity is obtained.

The blood velocity is impacted by the presence of body acceleration, as well as the yield stress associated with Casson fluid and as such, the process of dispersing the solute is distracted. It graphically illustrates how the blood velocity and the process of solute dispersion are affected by various factors, including the amplitude and lead angle of body acceleration, the yield stress, the gradient of pressure and the Peclet number.

It is witnessed that the blood velocity, the solute concentration and also the effective and relative axial diffusivities experience a drop when either of the amplitude, lead angle or the yield stress rises.

This paper aims to simulate the steady laminar mixed convection incompressible viscous and electrically conducting hybrid nanofluid (CuO-Cu/blood) flow near the plane stagnation-point over a horizontal porous stretching sheet along with an external magnetic field and induced magnetic field effects that can be applicable in the biomedical fields like the flow dynamics of the micro-circulatory system and especially in drug delivery.

The basic partial differential equations (PDEs) are altered to a set of dimensionless ordinary differential equations (ODEs) with the help of suitable similarity variables which are then solved numerically using bvp4c scheme from MATLAB. Inasmuch as validation results have shown a good agreement with previous reports, the present novel mass-based algorithm can be used in this problem with great confidence. Governing parameters are both nanoparticle masses, base fluid mass, empirical shape factor of both nanoparticles, suction/injection parameter, magnetic parameter, reciprocal magnetic Prandtl number, Prandtl number, heat source parameter, mixed convection parameter, permeability parameter and frequency ratio. The effect of these parameters on the flow and heat transfer characteristics of the problem is discussed in detail.

It is shown that the use of CuO and Cu hybrid nanoparticles can reduce the hemodynamics effect of the capillary relative to pure blood case. Moreover, as the imposed magnetic field enhances, the velocity of the blood decreases. Besides, when the blade shapes for both nanoparticles are taken into account, the local heat transfer rate is maximum that is also compatible with experimental observations.

An innovative mass-based model of CuO-Cu/blood hybrid nanofluid has been applied. The novel attitude to one-phase hybrid nanofluid model corresponds to considering nanoparticles mass as well as base fluid mass to computing the solid equivalent volume fraction, the solid equivalent density and also solid equivalent specific heat.

The purpose of this paper is to pursue two following main goals: first, theorizing a new concept named as equivalent bus load in order to make a promising simplification over power system analysis. Second, proposing an outstanding fast and simple approach based on introduced concept for voltage estimation after multiple component outages while satisfying required accuracy.

Equivalent load bus theory introduces three transfer matrices that describe power system topology. Mentioned matrices could be calculated simply after system reconfiguration without matrix inversion. Using transfer matrices a large-scale power system can be modeled by a simple two-bus power system from the viewpoint of any desired bus so that load flow calculation leads to same value. The analysis of simplified power system yields to extract a new incremental model based on equivalent bus load theory that will be distinguished as an outstanding fast method for voltage estimation aim.

A deep study for fast voltage estimation aim is dedicated to evaluate proposed method from the accuracy and quickness point of view and the outcomes are compared to a well-known method as Distribution Factors (DF). Results and computational times unveil that presented approach is more accurate and much faster.

A novel and new fast voltage estimation method for assessment of power system component outages is introduced.