Sharif Digital Repository

One of the unusual features of some ceramic materials is the piezoelectric effect. The piezoelectric effect results from the linear electromechanical interaction between the mechanical and electrical states in crystalline materials with no inversion symmetry. The piezoelectric effect is a reversible process: materials exhibiting the piezoelectric effect (the internal generation of electrical charge resulting from an applied mechanical force) also exhibit the reverse piezoelectric effect, the internal generation of a mechanical strain resulting from an applied electrical field. In the last decades, many research has been done on the use of these materials for the self-charging low-power... 

Audio signal processing is a greatly useful approach to the Internet of Things since analyzing prominent audio signals can provide valuable information about environmental activities. Environmental sound processing is used in applications such as mechanical systems diagnosis, industrial maintenance, security systems, etc. This approach requires the design and development of sound classification and detection systems. In this thesis, we have achieved 84.5% accuracy on optimizing the features (by feature engineering and feature learning) and exploiting different types of machine learning algorithms. Well-known databases such as ESC-50 have been used to test and evaluate the whole system. Among... 

Embedded systems are commonly used in industrial and non-industrial environments. The widespread usage of Internet and the connectivity it brings lead to the emergence of the Internet Of Things (IOT) which in turn leads to the increased usage of embedded systems. Smart things bringing intelligence to human life are just a small example of such systems.On one hand, embedded systems with a low-end processor have minimal capabilities, and on the other hand, the widespread usage of these systems make them an attractive goal for attackers. Embedded system security is not a new topic, but system connectivity over Internet and the remote access to them make this topic more important than...