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Abstract It has been well documented that the usage of a textured cover layer reduces reflection from the air‐solar cell interface, which ultimately enhances the power conversion efficiency (PCE) of a solar cell. The most commonly used patterns, such as pyramids, micropillars, nanowires (NW), and nanoholes have been widely studied and optimized. Besides using such NWs to enhance light absorption, this work also additionally considers the concept of mimicking the antireflection coating of single or multiple layers in minimizing the reflectance and thus enhancing the total absorptance further. It is shown here that at least one order of magnitude shorter multilayer NW pattern of 268 nm total height can outperform a standard NW of 4270 nm height, which needs less material and can also be fabricated at a reduced cost. Furthermore, the proposed design with reduced height has a significantly lower surface‐to‐volume ratio, which also reduces surface recombination loss than the other textured surface patterns. The results presented in this work have been comprehensively analyzed by initially optimizing optical absorption and then completing the electrical simulations. The optimized design in conjunction with a back reflector offers an efficiency as high as 16.434%.

Proportional-Integral-Derivative control is the most used kind of control which provides the simplest and most effective solution to different kinds of control engineering applications. But until now PID controller is poorly tuned in real life and online applications. While most of PID tuning is done manually. Switched reluctance motor (SRM) has highly nonlinear characteristics since the developed/produced torque of the motor has a nonlinear function on both phase current and rotor position. These nonlinearities of the SRM drives make the conventional PID (proportional + integral + Derivative) controller a poor choice for application where high dynamic performance is desired under all motor operating conditions. research paper comes up with two artificial and hybrid techniques involving Genetic Algorithm (GA) and Ant Colony Optimization (ACO). Those techniques where used to tune the PID parameters for the switched reluctance motor (SRM) and its performance were compared with the conventional method of “Ziegler Nichols. The results obtained reflects that, the use of those algorithms based controller improves the performance of the whole process in terms of a fast set point tracking and regulatory changes and also provides an optimum stability for the system itself with a minimum overshoot on the output signal.

Two new implantable cardioverter defibrillator systems developed for compatibility with magnetic resonance imaging demonstrate safety and efficacy in the Evera MRI and ProMRI trials, with no significant changes in ventricular pacing threshold < 5.0 V or ventricular sensing. In addition, there were no serious device-related events in both studies. [ABSTRACT FROM AUTHOR]

Background: Transesophageal echocardiography (TEE) has not been compared to transthoracic echocardiography (TTE) for assessment of left ventricular diastolic function (LVDF). Left ventricular diastolic dysfunction is common in systemic lupus erythematosus (SLE), a disease model of premature myocardial disease., Methods: 66 patients with SLE (mean age 36±12 years, 91% women) and 26 age-and-sex matched healthy volunteers (mean age 34±11 years, 85% women) underwent TEE immediately followed by TTE. From basal four-chamber views, mitral inflow E and A velocities, E/A ratio, E deceleration time, isovolumic relaxation time, septal and lateral mitral E' and A' velocities, septal E'/A' ratio, mitral E to septal and lateral E' ratios, and pulmonary veins systolic to diastolic peak velocities ratio were measured. Measurements were averaged over 3 cardiac cycles and performed by 2 independent observers., Results: LVDF parameters were worse in patients than in controls by TEE and TTE (all p≤0.03). Most LVDF parameters were similar within each group by TEE and TTE (all p≥0.17). By both techniques, mitral E and A, mitral and septal E/A ratios, septal and lateral E', septal and lateral E/E' ratios, and average E/E' ratio were highly correlated (r=0.64-0.96, all p≤0.003); E deceleration time, isovolumic relaxation time, and septal A' velocities were moderately correlated (r=0.43-0.54, all p≤0.03); and pulmonary veins systolic to diastolic ratio showed the lowest correlation (r=0.27, p=0.04)., Conclusion: By TEE and TTE, LVDF parameters were worse in SLE patients than in controls; and in both groups, LVDF parameters assessed by TEE and TTE were similar and significantly correlated., Competing Interests: Conflicts of Interest None.