Sharif Digital Repository

Ground reaction forces (GRFs) and their centers of pressure (CoPs) are essential inputs in musculoskeletal models of the spine that study load-lifting tasks. While GRFs and CoPs are usually measured in vivo via force-plates, they can be predicted based on motion equations, developed in AnyBody Modelling System (AMS) thus eliminating the need for laboratory equipment and in vivo measurements. This study aims to develop an easy-to-use yet accurate model that predict GRFs and CoPs during different Manual Material Handling (MMH) activities using AnyBody Modelling System and artificial neural networks. First, the accuracy of the AMS GRF prediction algorithm was evaluated for 8 normal- and 4... 

Existing face forgery detection methods mainly focus on certain features of images, such as features related to image noise, local textures or frequency statistics of images for forgery detection. This makes the extracted representations and the final decision depend on the data in the database and makes it difficult to detect forgery with unknown manipulation methods. Solving this challenge, which is called the generalization challenge in artificial intelligence literature, has become the main goal of researchers in this field. In this thesis, the focus is on extracting effective features for success in forgery detection and preventing the performance of the forgery detection network from... 

One of the most important problems in machine learning is investigating the performance of the learning algorithms, and especially deep neural networks, on adversarial examples, which are generated by imperceptibly perturbing input images, so that cause the model make a wrong prediction. Not only this line of research is important for making deep neural networks dependable, but also can help with understanding the fundamental limitations of deep neural networks, and the nature of their operation, which can in turn provide researchers with valuable insights into artificial intelligence. In this research work, we have tried to approach the topic with a mainly theoretical mindset. The method we... 

Wind energy technologies guarantee low pollution and operational costs. Using a DFIG and a fractionally rated power electronics converter gives variable speed operation with a low cost drive train. As energy policy organizations have allocated a considerable quota of wind energy generation to offshore wind farms, the absence of slip rings and brushes in the brushless DFIG (BDFIG) is an advantage for offshore wind turbines where maintenance is vital and expensive. With increasing wind power penetration in power systems, grid code requirements are an important consideration for the ride-through capability of wind farms through voltage dips, particularly for multi- MW wind turbine generators....