In this work, Silver Nanoparticles (AgNPs) were synthesized in water using either polymer assisted chemical reduction synthesis method or green synthesis. The obtained AgNPs were characterized by Dynamic Light Scattering (DLS) and UV-visible spectroscopy (UV-vis), and further tested for antibacterial activity to evaluate their potential use in wound healing. At first polyvinylpyrrolidone (PVP 10 KD) and Low-Molecular Weight Chitosan were used as coating agents during the reduction of silver nitrate with a strong reducing agent sodium borohydride (NaBH4). Our DLS results demonstrated that ...

The main objective of this work is to find a more straightforward method for estimating the parameters of an equally spaced discrete autoregressive process by using maximum likelihood estimation (MLE) considering it is challenging to obtain the parameters of a nonlinear optimization procedure. The resulting estimated values are tested through simulation and then compared with those obtained using the previous MLE and Yule-Walker estimation. The achieved result yields slightly increased accuracy. Another problem we tackle is the Yule-Walker estimators for the continuous autoregressive models ...

In this thesis, we have restudied a sample chosen by (Lusso & Risaliti, 2016) consisting of a set of 2,153 unique quasars given by two source catalogues: 3XMM-DR5 (Rosen et al., 2016) and DR7 catalogue (Shen et al., 2011). Quasars serve science in two different ways: 1) Understanding accretion physics by studying the physical mechanism occuring between the disk and cloud corona, and 2) they are good cosmological probes in distance estimation reaching redshifts ~ 7 (Mortlock et al., 2011). A physical relation has been observed between the optical-UV disk and the X-ray corona through a log-log ...

With the rise of the Internet, recommender systems are becoming a used solution to solve the information overload problem. These systems are like any other system, subject to noise: malicious noise that is caused by attacks and natural noise that is due to the human error. Many detection algorithms solve the noise problem. However, since natural noise and serendipity overlap in their definition, removing noise results in removing serendipity. Serendipity that is the happy surprise of finding something relevant unexpectedly is important for the issue of over personalization caused by the recommender ...

Cloud computing ecosystem is one of the trends currently being discussed in the domain of information technology and computing. Computing ecosystem allows smart usage of technology which means unneeded resources are saved such as power, computing resources, spaces for datacenters as well as saving huge amount of CO2 and electric circuit boards and machines. Cloud federation and its underlying techniques, is considered role model in sharing and expanding cloud business to provide better and cheaper services for end-users. In this thesis, we will survey and compare existing Identity Access Management ...

From ages to ages there had been expectation of individuals on a specific predictions and future occurrences. So also in a game, different participant that involves in those specified game have their various expectations of the results or the output of the game they are involved in. That is why we need a mathematical theory that helps in prediction of the future expectations in our day to day activities. Therefore the Martingale Theory is a very good theory that explains and dissects the expectation of a gamer in a given game of chance. So in this thesis, we shall talk about the Martin-gale ...

The Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA) is a test used to differentiate between humans and machines. In this thesis, we have implemented a deep neural network architecture to automatically recognize CAPTCHAs. The main idea behind this thesis is to test the reliability of test-based CAPTCHAs in differentiating between humans and machines. We utilized convolutional neural networks instead of the conventional strategies of CAPTCHA breaking which, typically, use segmentation techniques. Our model is comprised of 8 layers to learn textbased images; ...

Geometric measure theory could be described as differential geometry, generalized through measure theory to deal with maps and surfaces that are not necessarily smooth, and applied to the calculus of variations. Geometric measure theory is important because it studies sets, their variation and their boundaries (from the measure theoretic sense). In particular, a very interesting branch in Geometric measure theory, is the sets of locally finite perimeter. Just as their name actually shows, these sets are essentially sets whose perimeter is (locally) finite. In this thesis we start by giving a ...

During recent years, the practice of administering antibiotics to animal feed at sub-therapeutic levels has raised concern with consumers because of the apparent increase of antibiotic-resistant bacteria in the human food chain. Researchers have found that probiotics composed of naturally occurring beneficial live microbes such as bacteria (lactobacilli) could be the novel growth promoters. Supplementing poultry diet with probiotics has been found to improve growth performance, feed conversion efficiency, and immune responses, and help in combating enteric pathogens. The aim of this study is ...