Computer networks have expanded significantly in use and this makes them more vulnerable to attacks. It is really important to secure the data from any intrusive attacks so intrusion detection is really very helpful in the field of computer network security. Intrusion detection is the act of detecting unwanted traffic on a network. Many current intrusion detection systems are unable to find unk...

[1] Total ozone trends are typically studied using linear regression models that assume a first-order autoregression of the residuals [so-called AR(1) models]. We consider total ozone time series over 60 S–60 N from 1979 to 2005 and show that most latitude bands exhibit long-range correlated (LRC) behavior, meaning that ozone autocorrelation functions decay by a power law rather than exponentia...

.................................................................................................i Papers included in this thesis.............................................................iii My contribution to the papers...........................................................iv Acknowledgements ..............................................................................v

An upward trend in Ontario tornado frequency (about 1.6 tornadoes/decade with the statistically significant level at least at 95%) is identified using three independent approaches. The first method is the conventional linear regression method that had no disturbance to the original tornado time series. The second approach is to employ the Mann-Kendall test with consideration of removing a lag o...

Purpose Global analyses using mean deviation (MD) assess visual field progression, but can miss localized changes. Pointwise analyses are more sensitive to localized progression, but more variable so require confirmation. This study assessed whether cluster trend analysis, averaging information across subsets of locations, could improve progression detection. Methods A total of 133 test-retes...

Algorithms that enable the process of automatically mining distinct topics in document collections have become increasingly important due to their applications in many fields and the extensive growth of the number of documents in many domains. Traditionally, the task of topic discovery has been mainly addressed through algorithms that work on a snapshot view of the repository, which ignores the...

Dialogues are created by the interaction between people, who speak different kinds of topics using natural language. Task-oriented dialogue aims the solution of a given task in a given domain. Folksonomies are knowledge structures composed of users, tags and resources. Folksonomies emerge from the tagging process in collaborative tagging systems. Dialogues and folksonomies have in common their ...

Dynamic trend analysis is an important technique for fault detection and diagnosis. Trend analysis involves hierarchical representation of signal trends, extraction of the trends, and their comparison (estimation of similarity) to infer the state of the process. In this paper, an overview of some of the existing methods for trend extraction and similarity estimation is presented. A novel interv...

Network Intrusion Detection System (NIDS) is an important and practical tool for network security. To guarantee a precise detection the NIDS must detect packets at a wire speed. However, with the recent trend of high-speed networks, the capability of a single NIDS can not meet the speed’s demand, resulting in rising of false negatives. To promote the NIDS performance and efficiency, present stu...

Numerous applications, such as bank transactions, road traffic, and news feeds, generate temporal datasets, in which data evolves continuously. To understand the temporal behavior and characteristics of the dataset and its elements, we need effective tools that can capture evolution of the objects. In this paper, we propose a novel and important problem in evolution behavior discovery. Given a ...