Password Manager using Python Programming Language

A password manager is a software application that is used to store and manage the passwords that a user has for various online accounts and security features. Password managers store the passwords in an encrypted format and provide secure access to all the password information with the help of a master password. We are going to build this application using Python Programming language. Its design philosophy emphasizes code readability with the useof significant indentation

Estimation of elastic bandgaps in metastructures: A comparison of physics-based and data-driven approaches

Metastructures are an emerging solution for applications in aerospace, industry, and robotics, as they inhibit the propagation of elastic waves within a specific frequency range called the “bandgap”. Accurate estimation of bandgaps is crucial for optimizing metastructures for specific purposes. Two approaches have been traditionally used: physics-based modeling, which requires precise characterization of the unit cell\u27s physical properties, and data-driven methods based on steady-state dynamic response. This study compares the effectiveness of data-driven methods (Component Mode Synthesis and FRF-Based Substructuring) with traditional physics-based methods for identifying bandgaps in multi-unit cell metastructures. We also validate the identified bandgaps using experimental reading-based methods. Our goal is to determine a more efficient and accurate approach for identifying bandgaps in metastructures, with potential implications across various fields

ESTIMATION OF STRESS STATE IN AN AXIALLY LOADED BEAM USING MODAL DATA

Residual stresses are found to play a vital role in the dynamic behavior of the beam. These stresses are sometimes induced unintentionally due to manufacturing processes where temperate plays a role, while at other times, beams are subjected to stresses to alter their dynamic behavior for a particular application. Owing to the ubiquitous presence of the stressed beam, the estimation of its stress state becomes imperative to prevent structural failures. This study employs an approach to estimate the stress state of a beam from the natural frequencies and mode shapes. Using the modal data, the wave-numbers are calculated, and hence a dispersion relation is established. Modal analysis for a beam subjected to axial load is performed in a standard finite element software package, and the natural frequencies and the mode shapes are extracted. The analysis is performed for different values of loads, both compressive and tensile. The dispersion relation for the load cases is calculated, and the relationship between the wave-number, natural frequency, and load value is established using a curve-fitting approach. It was found that the discussed approach estimated the load value accurately. The discussed approach can be utilized to estimate the buckling of structures and stress states in a beam directly from the experimental data of the axially loaded beam

DATA-DRIVEN ESTIMATION OF BANDGAP FREQUENCIES IN METASTRUCTURES FOR ELASTIC WAVE ABSORPTION

This study investigates the elastic wave absorption behavior of metastructures in the bandgap frequency region. The bandgap region is estimated using data-driven methods based on the Frequency Response Function (FRF) of the unit cell of the metastructure. To achieve this, the unit cell is discretized using 1-D finite bar elements, and the numerical FRFs are calculated to dynamically link multiple unit cells using Component Mode Synthesis (CMS). The location of the bandgap is determined through the FRF of the multi-unit cell structure, which is referred to as Dynamically Linked Element Grade Oscillators (DLEGOs) due to the dynamic coupling between unit cells. The study also estimates the dispersion relation of the structure from the mode shapes of the finite structure. This approach is validated through the estimation of the bandgap from dispersion relations calculated using the traditional Finite Element Method. This comprehensive and validated method provides a way to estimate the edge frequencies of the bandgap in metastructures. The findings of this study contribute to the development of new metastructure designs that can inhibit elastic wave propagation in specific frequency ranges. Such designs have potential applications in various industries, including aerospace, defense, and transportation. In conclusion, this study highlights the importance of understanding the dynamic behavior of metastructures in modern engineering and their impact on various industries

PARAMETRIC-FEEL ALGORITHM: DEVELOPING A PARAMETRIC VECTORFITTING MODEL FOR EVENT LOCALIZATION IN CALIBRATED STRUCTURES

For smart structures, especially in the context of human activity, the force exerted and the location it happened is of significant relevance. This paper revisits and improves the performance in localizing and characterizing an input force with precalibrated structures through vibration measurement. The Force Estimation and Event Localization (FEEL) Algorithm have been discussed as a means of calculating the force of an impact and pinpointing its location. Unlike other time-of-flight approaches, FEEL does not require time synchronization, instead using transfer functions between possible impact locations and sensor locations to estimate force and localize impact. However, this approach is limited to locations where transfer functions are available. To overcome this limitation, a rowing hammer test was used to determine Frequency Response Functions (FRFs) at various points on a beam with a uniform rectangular cross-section. The Vector-Fitting algorithm was then used to improve the FRF approximation by moving poles to more advantageous locations, enhancing convergence, and lowering noise. Using the curve fitting approach, residues and FRFs were interpolated for additional locations. The extended FEEL algorithm was then used to localize impacts and estimate forces at these additional locations. This method can be used in applications such as tracking customer movement in retail establishments, detecting falls, tracking rehabilitation progress, and estimating building occupancy

NOVEL PUMPING MECHANISM FOR HEAT SINKS WITH FLUID MEDIUM USING STEADY STATE TRAVELING WAVES

The use of steady-state traveling waves as a novel pumping mechanism in liquid-cooled heat sinks offers a controlled and efficient method for fluid flow and heat removal without the need for an external fluid transfer pump. This experimental study demonstrates how traveling waves can be harnessed in a beam submerged in quiescent water using two force input methods, with the waves used to remove heat from a ceramic-based Positive Temperature Cofficient (PTC) heating element. The study analyzed the heating and cooling profiles of the heating element under two different conditions which are still water cooling and forced liquid convection cooling using steady-state traveling waves. The findings showed that a steady-state traveling wave could be an effective pumping mechanism for liquid-cooled heat sinks, resulting in lower maximum temperatures and equilibrium times than still-water cooling. These results suggest that optimizing the parameters like voltage and frequency could improve the performance of liquid-cooled heat sinks for various designs and operating conditions

Band Gap Estimation of D-LEGO Meta-structures Using FRF-Based Substructuring and Bloch Wave Theory

Periodic structures are found to exhibit band gaps which are frequency bandwidths where structural vibrations are absorbed. In this paper, meta-structures are built by dynamically linking oscillators in a periodic pattern, which are referred to as dynamically linked element grade oscillators or D-LEGOs. The location of the band gaps is numerically determined for a one-dimensional D-LEGO. The unit cell for the D-LEGO structure is considered to be made up of two longitudinal bar elements of different properties. For such a structure, the frequency response functions (FRFs) of a single unit cell are used to estimate the band gaps of a periodic-lattice structure by adapting the Bloch wave theory. Alternatively, the FRF of the multi-unit cell is determined using FRF-based substructuring (FBS) approach. The band gaps resulting from these two approaches are compared and verified