All control systems suffer from problems related to undesirable overshoot, longer settling times and vibrations while going form one state to another state. Most of relevant techniques had been in the form of suggesting modification and improvement in the instrumentation or interfacing part of the control system and the results reported, remain suffering from shortcomings related to hardware parameter dependence and maintenance and operational complexities. Present study was based on a software approach which was focusing on an algorithmic approach for programming a PIC16F877A microcontroller, for eliminating altogether the parametric dependence issues while adding the benefits of easier modification to suit a given control system to changing operational conditions. Said approach was first simulated using MATLAB/SIMULINK using the techniques of Proportional Derivative Fuzzy Logic Controller (PD-FLC) whose membership function, fuzzy logic rules and scaling gains were optimized by the genetic algorithm technique. Simulated results were verified by programming the PIC16F877A microcontroller with the algorithm and using it on a temperature control system where a fan was regulated in response to variations in the ambient system temperature. Resulting tabulated performance indices showed a considerable improvement in rising and settling time besides reducing overshoot and steady state error

High stability and water solubility of the fluorescent nano-materials are considered a key factor to evaluate their feasibility for fundamental applications. Herein, water soluble and thermally stable, green emitting carbon...

The present trend in radio design calls for the use of frequencies above 40 GHz for short links carrying wide-band digital communication signals. In order to utilize the new frequency band efficiently, signal attenuation studies due to duststorms is needed urgently for desert areas. This paper presents a mathematical model which has been developed to predict the signal attenuation due to duststorm. The proposed model enables the convenient calculation of the signal path attenuation based on Mie solution of Maxwell's equations for the scattering of electromagnetic wave by dust particles. The predicted values from the proposed mathematical model are compared with the measured values observed in Saudi Arabia and Sudan and show relatively close agreement.

Fluorescent sensing of temperature in nanoscale regions has many advantages and applications in the biological field. Herein, blue emitting carbon dots (CDs) are designed and successfully developed using a one step hydrothermal method. As synthesized CDs exhibit temperature dependent photoluminescent (PL) intensity and PL decay lifetime over the physiological temperature ranging from room temperature (RT) to 70 °C. The PL intensity and PL decay lifetime of the obtained CDs correlate linearly to temperature (RT−70 °C) with correlation coefficient of 0.997 and 0.996, respectively. Additionally, dual mode thermal sensing (PL intensity/lifetime) make these CDs a promising optical nanothermometer over alternative semiconductors quantum dots and CD-based quantum dots. Moreover, the resultant aqueous CDs demonstrate excitation-independent blue emission, and the PL quantum yield (QY) is reached at 44.5%. The obtained CDs illustrate stable performance to high ionic environments and photobleaching even after keeping them for 2 h under continues UV irradiation. Furthermore, blue emitting CDs have low cytotoxicity for T-ca. cells and illuminate deep blue fluorescence under the excitation of 406 nm. As a result, high thermal sensitivity of these fluorescent CDs has potential to detect temperature in living cells in the range of 25−40 °C.

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