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The demand for clean and sustainable alternative energy resources is linearly increasing day by day due to the prevailing electricity crisis. Small-scale energy harvesting is considered a sustainable way to generate clean energy. Advanced energy solar cells, mainly dye-sensitized solar cells use solar energy and convert it into electrical energy. Similarly, MEMS-based piezoelectric materials are used to convert mechanical energy into electrical energy. For these applications, zinc oxide is considered one of the most suitable materials with high conductive, tunable band gap, and piezoelectric properties. However, altering these properties can be carried out by the addition of metal and other materials. Various research work has been carried out to study the addition of conductive metal as a dopant to alter the properties of zinc oxide. In this study, Strontium has been doped in ZnO to form a nanostructure for application in DSSC and microelectromechanical systems (MEMS) energy harvesters. Analysis has been conducted using the simulation and fabrication method. The results show that the doping and the pore size of the substrate (Anodic Aluminum oxide membrane) largely affect the output voltage and current. The difference between the simulated and experimental results was less than 1%, which shows the accuracy of the simulation. Tuning of the band gap can be observed by the addition of Sr in the ZnO nanostructure. For microelectromechanical systems energy harvesters, Sr-doped ZnO nanostructures deposited on anodic aluminum oxide show 7.10 mV of voltage and 1.11 uA of current output. The addition of Sr doping in ZnO shows the improvement in the generated current and voltage for the energy harvester and the improvement in overall power conversion efficiency for dyesensitized solar cells. MEMS-based energy harvesting devices and low-cost advanced solar cells are promising to improve the efficiency of energy generation at a small scale. [ABSTRACT FROM AUTHOR]

Approximately 26% of adult people, mostly females, are affected by varicose veins in old age. It is a common reason for distress, loss of efficiency, and worsening living conditions. Several traditional treatment techniques (sclerotherapy and foam sclerotherapy of large veins, laser surgeries and radiofrequency ablation, vein ligation and stripping, ambulatory phlebectomy, and endoscopic vein surgery) have failed to handle this disease effectively. Herein, authors have presented an alternative varicose vein implant method--the descending sinusoidal microchannel (DSMC). DSMC was simulated by Fuzzy logic MATLAB (The MathWorks, Natick, MA, USA) and ANSYS (ANSYS 18.2, perpetual license purchased by Ibadat Education Trust, The University of Lahore, Pakistan) with real and actual conditions. After simulations of DSMC, fabrication and testing were performed. The silver DSMC was manufactured by utilizing a micromachining procedure. The length, width, and depth of the silver substrate were 51 mm, 25 mm, and 1.1 mm, respectively. The measurements of the DSMC channel in the silver wafer substrate were 0.9 mm in width and 0.9 mm in depth. The three descending curves of the DSMC were 7 mm, 6 mm, and 5 mm in height. For pressure, actual conditions were carefully taken as 1.0 kPa to 1.5 kPa for varicose veins. For velocity, actual conditions were carefully taken as 0.02 m/s to 0.07 m/s for these veins. These are real and standard values used in simulations and experiments. At Reynolds number 323, the flow rate and velocity were determined as 1001.0 (0.1 nL/s), 11.4 cm/s and 1015.3 (0.1 nL/s), 12.19 cm/s by MATLAB (The MathWorks, Natick, MA, USA) and ANSYS simulations, respectively. The flow rate and velocity were determined to be 995.3 (0.1 nL/s) and 12.2 cm/s, respectively, at the same Reynolds number (323) in the experiment. Moreover, the Dean number was also calculated to observe Dean vortices. All simulated and experimental results were in close agreement. Consequently, DSMC can be implanted in varicose veins as a new treatment to preserve excellent blood flow in human legs from the original place to avoid tissue damage and other problems. [ABSTRACT FROM AUTHOR]

Bioengineered veins can benefit humans needing bypass surgery, dialysis, and now, in the treatment of varicose veins. The implant of this vein in varicose veins has significant advantages over the conventional treatment methods. Deep vein thrombosis (DVT), vein patch repair, pulmonary embolus, and tissue-damaging problems can be solved with this implant. Here, the authors have proposed biomedical microdevices as an alternative for varicose veins. MATLAB and ANSYS Fluent have been used for simulations of blood flow for bioengineered veins. The silver based microchannel has been fabricated by using a micromachining process. The dimensions of the silver substrates are 51 mm, 25 mm, and 1.1 mm, in length, width, and depth respectively. The dimensions of microchannels grooved in the substrates are 0.9 mm in width and depth. The boundary conditions for pressure and velocity were considered, from 1.0 kPa to 1.50 kPa, and 0.02 m/s to 0.07 m/s, respectively. These are the actual values of pressure and velocity in varicose veins. The flow rate of 5.843 (0.1 nL/s) and velocity of 5.843 cm/s were determined at Reynolds number 164.88 in experimental testing. The graphs and results from simulations and experiments are in close agreement. These microchannels can be inserted into varicose veins as a replacement to maintain the excellent blood flow in human legs. [ABSTRACT FROM AUTHOR]

Microsatellites or short sequence repeats are widespread genetic markers which are hypermutable 1-6 bp long short nucleotide motifs. Significantly, their applications in genetics are extensive due to their ceaseless mutational degree, widespread length variations and hypermutability skills. These features make them useful in determining the driving forces of evolution by using powerful molecular techniques. Consequently, revealing important questions, for example, what is the significance of these abundant sequences in DNA, what are their roles in genomic evolution? The answers of these important questions are hidden in the ways these short motifs contributed in altering the microbial genomes since the origin of life. Even though their size ranges from 1 - to- 6 bases, these repeats are becoming one of the most popular genetic probes in determining their associations and phylogenetic relationships in closely related genomes. Currently, they have been widely used in molecular genetics, biotechnology and evolutionary biology. However, due to limited knowledge; there is a significant gap in research and lack of information concerning hypermutational mechanisms. These mechanisms play a key role in microsatellite loci point mutations and phase variations. This review will extend the understandings of impacts and contributions of microsatellite in genomic evolution and their universal applications in microbiology. [ABSTRACT FROM AUTHOR]

Conventionally, a flexural plastic hinge is designed and detailed at the core wall base and coupling beams ends to control the seismic responses. This strategy is based on allowing the damage to be concentrated on main structural components. To avoid such damage, an alternative strategy using energy dissipating devices (EDDs) such as buckling restrained braces (BRBs) is being studied and implemented nowadays. In this study, effect of BRBs locations on forty- (40-) story high-rise RC core wall case study building has been studied in detail using Nonlinear Response History Analysis (NLRHA) for seven spectrally matched ground motions. BRBs have been installed at critical locations identified with respect to the maximum DBE elastic modal racking shear deformation demands and force (shear and moment) demands in three different options. The force, deformation, and energy demands on structural components are compared for conventional design and different options of BRBs. The comparison with conventional design shows that BRBs not only are effective for reducing shear force demand along wall height, bending moment demand at mid height, and deformation demands by 10%, 45%, and 45%, respectively, but significantly reduce the rotation and energy demands in the core wall by 90% and 250%, respectively. [ABSTRACT FROM AUTHOR]

This paper presents the design and simulation of MEMS based energy harvester controller. Energy harvesting from physical motion such as finger motion, heart beating, walking and running are becoming so important now-a-days. In this study outputs voltage and current of the MEMS based energy harvester can be controlled by using fuzzy logic based control system. A new way of controlling the outputs by changing the inputs has been proposed in this study. The system has been developed in MATLAB using fuzzy logic Mamdani model.Two inputs pressure and area have been selected. The three membership functions to the input parameters have been assigned. The two outputs like voltage and current are selected for output power. Three membership functions are also assigned to the outputs. The system works according to the rules defined in the fuzzy inference system (FIS). The results according to suggested rules belonging to assigned MFs have been displayed in surface viewer.Different rules of combinations were defined in MATLAB rule editor and we used AND logic for simulation. The rsults obtained from fuzzy logic controller have been verified by using Mamdani's formula for specific values of the inputs and the outputs. As there is only 1% error for both the outputs, current and voltage, this shows that the system performs very well. [ABSTRACT FROM AUTHOR]

This paper presents the design and simulation of flow controller of dams gates using fuzzy logic based control system. A new way of controlling the opening and closing of dam gates has been proposed in this study. The system has been developed firstly in MATLAB using fuzzy logic Mamdani model and then the system is checked by developing a simple C language code using Microcontroller. Two input parameters have been selected like water level and water speed. The three membership functions to these parameters have been assigned. The one output parameter is selected as flow controller. Three membership functions are also assigned to the output. In this study the system works according to the rules defined in the fuzzy inference system. The simulation results are compared with the calculated results of mamdani formula. A pseudo code is developed from the rules defined in the FIS and code is generated in C language. The C language code is then burnt in the Atmel 89C51 microcontroller and a simple control circuit is developed to check the software results on practical basis. The basic concept of the study is that this system will show extreme response on extreme condition otherwise it will show normal results. When both inputs are in the higher (high water level and fast speed) region the output results will also be in the higher region (dam gates full open). This system showed great efficiency and robustness as it can be easily seen from the observations. This system is much different from the conventional systems as it involves simple microcontroller circuit. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, design and simulation of piezoelectric actuator has been presented. The fluid flow rate using MP6 PTZ micropump for artificial kidney has also been studied. The piezoelectric actuator consists of silicon membrane and piezoelectric disk. Finite element method (FEM) using ANSYS has been used for simulation. The maximum displacement 3.6μm occurs in the silicon membrane at the center at applied 100V for frequency 200Hz. Fluid flow rate using commercially available PZT MP6 micropump has been investigated for artificial kidney system. DI water and heparin have been considered as fluid during experiments. The flow rate has been controlled by adjusting the voltage and frequencies. Experimental results show that the MP6 pump is suitable for heparin infusion in our ongoing project for wearable artificial kidney. The presented research work provides useful information and predicted data to develop the optimized design of piezoelectric actuator to develop micropump for artificial kidney system. [Copyright &y& Elsevier]

In this research work, Polydimethylsiloxane (PDMS) has been used for the fabrication of microchannels for biomedical application. Under the internet of things (IoT)-based controlled environment, the authors have simulated and fabricated bio-endurable, biocompatible and bioengineered PDMS-based microchannels for varicose veins implantation exclusively to avoid tissue damaging. Five curved ascending curvilinear micro-channel (5CACMC) and five curved descending curvilinear micro-channels (5CDCMC) are simulated by MATLAB (The Math-Works, Natick, MA, USA) and ANSYS (ANSYS, The University of Lahore, Pakistan) with actual environments and confirmed experimentally. The total length of each channel is 1.6 cm. The diameter of both channels is 400 µm. In the ascending channel, the first to fifth curve cycles have the radii of 2.5 mm, 5 mm, 7.5 mm, 10 mm, and 2.5 mm respectively. In the descending channel, the first and second curve cycles have the radii of 12.5 mm and 10 mm respectively. The third to fifth cycles have the radii of 7.5 mm, 5 mm, and 2.5 mm respectively. For 5CACMC, at Reynolds number of 185, the values of the flow rates, velocities and pressure drops are 19.7 µLs−1, 0.105 mm/s and 1.18 Pa for Fuzzy simulation, 19.3 µLs−1, 0.1543 mm/s and 1.6 Pa for ANSYS simulation and 18.23 µLs−1, 0.1332 mm/s and 1.5 Pa in the experiment. For 5CDCMC, at Reynolds number 143, the values of the flow rates, velocities and pressure drops are 15.4 µLs−1, 0.1032 mm/s and 1.15 Pa for Fuzzy simulation, 15.0 µLs−1, 0.120 mm/s and 1.22 Pa for ANSYS simulation and 14.08 µLs−1, 0.105 mm/s and 1.18 Pa in the experiment. Both channels have three inputs and one output. In order to observe Dean Flow, Dean numbers are also calculated. Therefore, both PDMS channels can be implanted in place of varicose veins to have natural blood flow. [ABSTRACT FROM AUTHOR]

Fuzzy logic-based control systems are widely used in various fields like home appliances, medical instruments, automobiles, textile machinery, agriculture equipment and aviation for process control and data analysis. Fuzzy logic technique has shown great potential to solve the complex problems of physical world due to similarity with human understanding. Its advancements have gained widespread attention in different research areas. In several cases, it is very suitable for electronic devices which need to be precisely self-powered. In this work, an ANSYS-based simulation, fuzzy analysis, development and testing of a microelectromechanical system (MEMS)-based energy harvester have been presented. Zinc oxide (ZnO) nano rods were synthesized on an anodic aluminum oxide (AAO) template to form the MEMS energy harvester and study the effect of energy generation by applying force. The power of 5.16 nano Watts has been obtained by taking the numerical value of voltage (Voc) and current (Isc) as 3.16 mV and 0.985 µA respectively using fuzzy logic tool. Experimental testing of the harvester shows that the range of Voc is 3–6.4 mV and Isc is 0.45–1.5 μA. The results depict that this device can be used for touch screens to generate energy that can be further utilized for charging smart devices. [ABSTRACT FROM AUTHOR]