In this paper, design and assembly of a new phase-shift range finder and also the cross-talk effect and the effect of intermediate Frequency (IF) deviation on the range finder, is presented. Using the heterodyne technique, the system was able to measure very small phase-shifts, hence, considerably increasing the accuracy of the distance measurements. Since the major error in such systems is due to the phase measurement (counter-clock pulse), related to the cross-talk and the Frequency shift, it was necessary to take especial steps to decrease these errors. Therefore, after testing the system, practically a simulation of the system was also carried out. Using the simulation results, the error due to the cross-talk was about 2% in the worst condition. The error related to the Frequency changes was about zero, and the resolution due to the counter-clock pulse became 21 mm. Considering the signal to noise ratio of 20dB and the noise current of 42.8pA at the input current to voltage inverter, the lowest detectable optical power at the APD input, which the noise could be ignored, was 23 pW.

In this paper, the vibrations of thin plate in modified couple stress thermoelastic medium by using Kirchhoff- Love plate theory has been investigated. The governing equations of motion and heat conduction equation for Lord Shulman (L-S) [1] theory are written with the help of Kirchhoff- Love plate theory. The thermoelastic damping of micro-beam resonators is analyzed by using the normal mode analysis. The solutions for the free vibrations of plates under clamped-simply supported (CS) and clamped-free (CF) conditions are obtained. The analytical expressions for thermoelastic damping of vibration and Frequency shift are obtained for couple stress generalized thermoelastic and coupled thermoelastic plates. A computer algorithm has been constructed to obtain the numerical results. The thermoelastic damping and Frequency shift with varying values of length and thickness are shown graphically in the absence and presence of couple stress for (i) clamped-simply supported, (ii) clamped-free boundary conditions. Some particular cases are also presented.

The computational investigation of change in the infrared vibrational Frequency of some Schiff base-transition metal complexes relative to that observed in the Schiff base ligand was performed using density functional theory (DFT) based on the hybrid functional of three parameters Becke-3-Lee-Yang-Parr (B3LYP) with 6-31G(d,p) basis set. All the calculations were carried out using the Gaussian 09 program package, and the data obtained from the frontier molecular orbitals of the optimized ligand and its complexes showed that the complexes were less stable and more reactive than the ligand. The infrared vibrational frequencies of the Schiff base functional group had lower stretching vibrations in the complexes than the ligand, with the appearance of new vibrational frequencies therein not observed in the spectrum of the ligand. These observations can be used to confirm bond formation between a Schiff base and a transition metal in chemical synthesis.

This study introduces a new approach to Pulse Width Modulation (PWM) known as the adapted DC level shift PWM technique (DC-PWM), which is applied to a nine level modular multilevel converter. This modulation technique involves interleaving the modulated waveform with a Direct Current (DC) level, while ensuring that quarter wave symmetry is preserved. By implementing an adjusted level shift 1/4 DC-phase disposition (PD) PWM and 2/4 DC PDPWM modulation technique, the switching Frequency of the Nine level Modular Multilevel Converter (MMC) has been successfully reduced. The technique's effectiveness has been confirmed through validation using Simulink/MATLAB and an experimental setup. The simulation results show a notable decrease in the Frequency of action switching. When it comes to harmonic performance for phase voltage, line voltage, and capacitor voltage, the Type-3 1/4 DC-PDPWM technique generally outperforms the 2/4 DC-PDPWM technique. The 2/4 DC-PDPWM Type-2 demonstrates impressive performance, particularly in terms of phase current and capacitor voltage %THD. The selection of these techniques will be determined by the specific performance needs and the trade-offs in complexity and harmonic suppression that are deemed acceptable for the intended use.