Today, rate at which cement is utilized is a lot higher than it was fifty years prior. Major problem faced with concrete is the occurrence of micro-cracks, which affects strength and durability concrete. By avoiding micro-fissures at the initial stage of conversion of ettringite into C-S-H gel, leads to impermeable concrete. By adding Bio-cement, as additive to cement, will develop Microbiologically Induced Calcium Precipitate (MICP), fills pores formed in the concrete at the initial age itself. By the combined action of MICP and C-S-H gel, leads to dense concrete, improves solidity and sturdiness of concrete. Bio-cement was combination of Bacillus.Pasteurii (5%) and 95% nutrients (Urea and Calcium lactate). This paper was about Bio-cement as additive taken 0.5%,1%,1.5% and 2% by weight of cement for M25 mix, and concluded that 1% as optimized value after analysing compressive strength , flexural strength results. Durability studies which including Sulphate attack, Acid attack, Sorptivity and RCPT for M25 concrete, at optimized 1% addition of Bio-cement. Comparative test results were presented for Weight loss, loss of compressive strength, Sorptivity coefficient and charge passed in Coulombs, to conventional concrete and Bio-concrete analysed after 28, 56 and 90 days of immersion.

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The optical and thermal properties of prepared epoxy/silica composites with different concentration were studied. The optical properties were studied in the UV-visible wavelength range (400-800 nm). Thermal properties were studied as a function of temperature and filler content. The observed physical constants of the thin films like optical energy gap, energy gap tails, thermal conductivity, and thermal resistivity were determined. It was found that these measured quantities vary with the incident UV-wavelength, silica content, and temperature. The absorption coefficient and the optical band energy gap (Eopt) have been obtained from non-direct allowed transitions in k-space at room temperature. The width of the tails of localized states in the band gap (?E) was evaluated using the Urbach-edges method. It was found that both (Eopt) and (?E) vary with the concentration of silica in the composite. The thermal conductivity and thermal resistivity of epoxy/silica composite have been studied as a function of temperature. It was found that the thermal conductivity increases with temperature and silica concentration.

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For complex nonlinear control systems, using an individual fuzzy logic controller or a conventional PID controller cannot satisfy the requirements of these systems. A PID controller had been previously designed, and has been redesigned in the current research using the Ant Lion Optimization (ALO) algorithm to determine the gains of the PID controller necessary to achieve the desired speed for a single-phase induction motor (SPIM). A Fuzzy logic controller was subsequently designed, and the fuzzy rules and membership functions were used to find the controller gains built on the input variable error and the derivative error signals. However, the simulation results of both the PID and Fuzzy logic controllers could not give satisfactory results for the SPIM. To overcome these problems, a novel hybrid controller was developed that is a combination of fuzzy logic and the proportional (P), integral (I) and differential (D) controllers. This is also called as Fuzzy rule based PID controller. The experimental results from this development demonstrated the technical and operational feasibility of this controller which produces fast rise time, fast setting time, and minimum steady state errors as well as improvements in other parameters. When the simulation results of the three controllers were compared, the Fuzzy rule based PID controller demonstrated the best performance parameters of the three.

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SRAM are very important in modern area. Because of scaling the CMOS characteristics are not holding good at lower technology nodes. To overcome the adverse effects facing in MOSFET due to scaling researchers are looking for substitute and FINFET found to be one of the right substitutes as its conserve less power, eliminates short channel effects and reduces leakage current. The problems associated with scaling of the device are higher sub threshold conduction, increased junction leakage and high leakage power there by increasing the power dissipation. Now days because of portable devices that work on battery has increased drastically the electronic products designed have to consume less power dissipation so that the device can work for longer time. As the scaling of technology done so vigorously the leakage power is comparable to dynamic power. As power consumed by the device to have less power dissipation the leakage power must be reduced this in turn consumes less power. So FINFET SRAM with different leakage current reduction techniques analyzed which in turn leads to reduce its leakage power. Because of scaling power supply is reduced in accordance with that threshold voltage is also to be reduced. Because of decrease in threshold voltage leakage power is increasing drastically at lower nodes of technology. To reduce the leakage power different leakage current reduction techniques are analyzed and hybrid technique is the best for design of low leakage current reduction which in turn have low power dissipation.

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This paper deals with the problem of voltage and current control of voltage source inverters (VSIs) with LC output filter. The objective is to achieve voltage regulation and reference tracking while ensuring current stability and regulation despite the unknown disturbances. In this work a model predictive control approach is proposed for three-phase VSIs with LC output filter control. The proposed controller has a cascade structure and it is designed in the synchronous reference frame d-q. The outer loop is for voltage control and the inner loop is for current control. A model predictive controller is developed for robust voltage regulation and reference tracking despite the unknown disturbances. The current controller uses PI controllers for current regulation and feed forward terms to decouple the direct and quadrature components of voltage and current control loops. Unlike the conventional PI-based synchronous reference frame VSI control, the proposed approach provides better control performance with smaller and smoother control signal and enables the d-q components of voltage and current to be fully decoupled. A comparative simulation study with the conventional control system is provided to highlight the efficiency of the proposed approach.

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This paper shows the structure of a double loop hybrid system developed as a software tool to support the identification of fissures and fractures in bone structures from radiological images. The proposed scheme uses two recognition loops with completely different design paradigms (hence its classification as a hybrid system), but whose independent results complement each other to offer a high-performance tool. The first loop is developed from digital image processing, here is used an algorithm for labeling and identification of the region of interest (ROI), and morphological operations on it for damage detection. The second loop uses deep learning to build a neural model capable of categorizing images with bone damage. The result of the two loops is combined by an inference machine that allows identifying images with damage with an overall accuracy above 80%.

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The aviation fuel of grade Jet A1 is one of the most used petroleum-derived jet fuels worldwide. The aviation industry, in coordination with standards setting organizations, has developed specifications, fuel handling practices and quality control procedures to ensure the integrity of jet fuel throughout its supply chain. A key aspect of jet fuel integrity is its potential contact and mixing with traces of free water, which occurs regularly in aviation fuel systems. The aim of this work was to perform an experimental evaluation of the effect of a mixing process of free water and jet fuel on chemical composition and fuel properties. The most relevant change in chemical composition occurred in the total content of naphthenic hydrocarbons. Specifically, a decrease in the content of naphthenic hydrocarbons with a lower number of carbon atoms per molecule was identified. Since the water content of all tested samples was similar, the changes in composition and physical properties were due to a loss of volatile compounds induced by the mixing process. Accordingly, there was an increase in density (decrease in API gravity), flash point, kinematic viscosity, initial boiling point, and the T10 point.

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The purpose of present study is to analyse the influence of chemical reaction on MHD Casson nanofluid flow on an elongating sheet taken into the account of radiation and heat absorption/generation. The governing nonlinear PDE’s are changed into a nonlinear ODE’s by using similarity transformations. The converted equations are solved using numerical technique is notable as Keller box method. The consequence of heat source/sink, Prandtl number, Casson parameter, magnetic field, Brownian motion, thermophoresis, thermal radiation and chemical reaction parameters on velocity, temperature, and concentration profiles are depicted and elucidate in physical terms. A resemblance with previously issued results shown a perfect agreement. Numerical values of physical quantities, such as velocity gradient, heat transfer rate and the mass transfer rate are arranged in tabular form.

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Over the years, there has been a growing concern about Nigeria's electricity supply which has been under stress for a long time. This is partly due to the fact that electricity demand is rising rapidly, which has exceeded capacity for generation. Therefore, it is very important to assess the contribution of potential numerous measures of demand-side to off-peak load. In the housing sector, water heating is the area with the highest consumption of electricity. This gives the highest chance to generally save consumption of power and reduce high power consumption. This paper, therefore, proposes a model that can automatically disconnect residential water heaters during the day's peak periods. An hourly model for consumption of electricity was used to assess the effects on the disconnection load. This proposed model is a control strategy that is fuzzy logic-based to adjust the regular power requirement of the conventional water heater from the high demand of electricity to low peak periods. This work concludes by presenting a review of results and analysis of simulation result from a certain experiment which shows that the strategy proposed in this work can swing the average demanded power from water heater to expand the residential load profile load factor.

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This paper proposes the design and implementation of one of the final stages in any production process using cooperative robotics and an organization based on ant colonies. The document presents a system focus on the selection and packaging; commonly, final steps in an industrial system. The strategy addressed using robotic mechanisms that emulate the ant's behavior in a colony, converting every stage into an efficient, flexible, effective process, even in the presence of production changes.

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In this work proposed multi-objective optimization technique of taguchi based Grey relational analysis (GRA) coupled with principal component analysis (PCA) in order to select the optimal processes parameters to minimize the delamination damages during drilling of GFRP composites. Experiments are designed as per the Taguchi L9 orthogonal array. The process parameters selected for experimentation as feed, specimen thickness, cutting speed and fiber orientation. Experimental results are statistically analysed using ANOVA. From the analysis it is found that feed is the most influencing parameter of delamination.

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In this work, two controllers, a Proportional Integral (PI) and a Model-based Predictive Controller (MPC), have been designed to regulate a DC/DC Cuk converter. First, the modeling and linearization of the system was performed using a frequency response estimation method. Then the PI controller was designed around a certain setpoint. Next, an algorithm was designed according to the Extended Prediction Self-Adaptive Control (EPSAC). Finally, the performance of the controllers was evaluated for setpoint tracking and disturbance rejection.

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In this document, a horizontal three-phase crude oil separator’s automation for the polyphase fluid treatment and the control system integration to the SCADA network (Supervisory Control And Data Acquisition) system are implemented. Knowing the separator’s operating principle and the optimum efficiency point that allows a continuous three phases flow (gas, water, and crude) without contamination between them are studied to develop this task. Likewise, the operation and the instrument configuration are investigated for the adequate control of the main variables of pressure, level, and flow within the normal operating fluid parameters such as density, viscosity, and temperature. The control system is developed using PLC (Programmable Logic Controller) to govern the pressure valves and level control loops and achieve the data visualization locally and remotely. The result is a fully automated process that has allowed the treatment of a larger fluid flow from the reservoir polyphase. Consequently, it increases the productivity and efficiency of the oil production plant. The control system works correctly, and the data is sent graphically through an interactive interface. This interface allows the operator to manipulate the process and set alarm levels for pressure variables, level, and setpoints for control valves.

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