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We consider the propagation of a shallow-water undular bore over a gentle monotonic bottom slope connecting two regions of constant depth, in the framework of the variablecoefficient Korteweg -de Vries equation. We show that, when the undular bore advances in the direction of decreasing depth, its interaction with the slowly varying topography results, apart from an adiabatic deformation of the bore itself, in the generation of a sequence of isolated solitons -an expanding large-amplitude modulated solitary wavetrain propagating ahead of the bore. Using nonlinear modulation theory we construct an asymptotic solution describing the formation and evolution of this solitary wavetrain. Our analytical solution is supported by direct numerical simulations. The presented analysis can be extended to other systems describing the propagation of undular bores (dispersive shock waves) in weakly non-uniform environments.

In this paper, we propose an anti-phishing method to protect Internet users from the phishing attacks. The scope of our study is on the Internet phishing, particularly focusing on the detection of phishing website. In order to do that, our proposed method will render a screenshot of the webpage and segment the region of interest, which consists of the website logo. Next, we will utilize Google image database to identify the website identity based on the segmented website logo. During the identification process, we employ the content-based image retrieval mechanism provided in Google Image Search engine to locate the most similar logo from Google image database. The returned results will reveal the real identity of the website. With the real identity, we can differentiate a phishing website from the legitimate website by assessing the domain name of the query website. The conducted experiments show promising results and our findings prove that we can effectively detect a phishing website when we manage to determine the real identity of a website.

We consider the propagation of an internal solitary wave over two different types of varying depth regions, i.e. a gentle monotonic bottom slope connecting two regions of constant depth in two-layer fluid flow and a smooth bump. Here, we let the depth of the upper layer is smaller than the lower layer such that an internal solitary wave of negative polarity is generated. The appropriate model for this problem is the variable-coefficient extended Korteweg-de Vries equation, which is then solved numerically using the method of lines. Our numerical results show different types of transformation of the internal solitary wave when it propagates over the varying depth region depending on the depth of the lower layer after the varying depth region including generation of solitary wavetrain, adiabatic and non-adiabatic transformation of the internal solitary wave.