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Network Intrusion Detection: Monitoring, Simulation And Visualization, Mian Zhou Jan 2005

Network Intrusion Detection: Monitoring, Simulation And Visualization, Mian Zhou

Electronic Theses and Dissertations

This dissertation presents our work on network intrusion detection and intrusion sim- ulation. The work in intrusion detection consists of two different network anomaly-based approaches. The work in intrusion simulation introduces a model using explicit traffic gen- eration for the packet level traffic simulation. The process of anomaly detection is to first build profiles for the normal network activity and then mark any events or activities that deviate from the normal profiles as suspicious. Based on the different schemes of creating the normal activity profiles, we introduce two approaches for intrusion detection. The first one is a frequency-based approach which …

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Isram: Information Security Risk Analysis Method, Bilge Karabacak, Ibrahim Sogukpinar Jan 2005

Isram: Information Security Risk Analysis Method, Bilge Karabacak, Ibrahim Sogukpinar

All Faculty and Staff Scholarship

Continuously changing nature of technological environment has been enforcing to revise the process of information security risk analysis accordingly. A number of quantitative and qualitative risk analysis methods have been proposed by researchers and vendors. The purpose of these methods is to analyze today's information security risks properly. Some of these methods are supported by a software package. In this study, a survey based quantitative approach is proposed to analyze security risks of information technologies by taking current necessities into consideration. The new method is named as Information Security Risk Analysis Method (ISRAM). Case study has shown that ISRAM yields …

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A Realization Of Sc-Cnn-Based Circuit Using Ftfn, Eni̇s Günay, Esma Uzunhi̇sarcikli, Recai̇ Kiliç, Mustafa Alçi Jan 2005

A Realization Of Sc-Cnn-Based Circuit Using Ftfn, Eni̇s Günay, Esma Uzunhi̇sarcikli, Recai̇ Kiliç, Mustafa Alçi

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a realization of the State Controlled Cellular Neural Network (SC-CNN)-based circuit using Four Terminal Floating Nullor (FTFN) as active element is presented. In this realization, a new version of autonomous Chua's circuit has been considered using FTFN realization of SC-CNN-based circuit. The performance of the proposed SC-CNN-based circuit is demonstrated by PSpice simulations.

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Prior Knowledge Input Method In Device Modeling, Serdar Heki̇mhan, Serdar Menekay, N. Serap Şengör Jan 2005

Prior Knowledge Input Method In Device Modeling, Serdar Heki̇mhan, Serdar Menekay, N. Serap Şengör

Turkish Journal of Electrical Engineering and Computer Sciences

The artificial neural networks are being used in modelling electronic elements and devices especially at microwave frequencies where non-linearity and dependence on frequency cannot be neglected. In this paper, instead of using artificial neural networks as a unique modelling device prior knowledge input method based on feed-forward artificial neural network structures as multi-layer perceptrons and wavelet-based neural networks is investigated. The benefits of prior knowledge input method over plain usage of artificial neural networks in modelling BJT is explored by comparing models obtained with and without prior knowledge input. The novelty of the paper is utilizing wavelet-based neural networks as …

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Transformer Protection Using The Wavelet Transform, Okan Özgönenel, Güven Önbi̇lgi̇n, Çağri Kocaman Jan 2005

Transformer Protection Using The Wavelet Transform, Okan Özgönenel, Güven Önbi̇lgi̇n, Çağri Kocaman

Turkish Journal of Electrical Engineering and Computer Sciences

This paper introduces a novel approach for power transformer protection algorithm. Power system signals such as current and voltage have traditionally been analysed by the Fast Fourier Transform. This paper aims to prove that the Wavelet Transform is a reliable and computationally efficient tool for distinguishing between the inrush currents and fault currents. The simulated results presented clearly show that the proposed technique for power transformer protection facilitates the accurate discrimination between magnetizing inrush and fault currents in transformer protection.

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Multilayer Capacitor Model Of The Earth's Upper Crust, Berk Üstündağ, Özcan Kalenderli̇, Haluk Eyi̇doğan Jan 2005

Multilayer Capacitor Model Of The Earth's Upper Crust, Berk Üstündağ, Özcan Kalenderli̇, Haluk Eyi̇doğan

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, an equivalent electric circuit model of Earth's upper crust is proposed to explain the behavior of measurement patterns acquired from network of the earthquake forecast project. A multi-layer capacitor model having active components that couples with the monopolar probe close to the surface is used to determine earthquake precursory patterns due to structural changes in time. Equivalent circuit model was developed for a) dilatency process that is assumed to be a stress weakening reason and b) external force source that increases shear stress over the fault until sudden decrement before the earthquake. A data acquisition system consisting …

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A Robustness Analysis Procedure For Realistic Missiles, Reşat Özgür Doruk, Erol Kocaoğlan Jan 2005

A Robustness Analysis Procedure For Realistic Missiles, Reşat Özgür Doruk, Erol Kocaoğlan

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a robustness analysis procedure for short range realistic missile autopilots. The sensitivity of the autopilots to the aerodynamic parameter uncertainties is investigated through the structured singular value theory where the results are verified through nonlinear simulations. Different types of perturbations are implemented in order to measure the complete performance of the missile.

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Implementation Of A New Self-Tuning Fuzzy Pid Controller On Plc, Onur Karasakal, Engi̇n Yeşi̇l, Müjde Güzelkaya, İbrahi̇m Eksi̇n Jan 2005

Implementation Of A New Self-Tuning Fuzzy Pid Controller On Plc, Onur Karasakal, Engi̇n Yeşi̇l, Müjde Güzelkaya, İbrahi̇m Eksi̇n

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, the self-tuning method for fuzzy PID controllers that has been developed in a previous study of the authors is implemented on PLC in order to control some standard processes formed on FEEDBACK PCS 327 Process Control Simulator. In this tuning method, the input scaling factor corresponding to the derivative coefficient and the output scaling factor corresponding to the integral coefficient of the fuzzy PID controller are adjusted using a fuzzy inference mechanism with a new input called ``normalized acceleration''. The results of the implementation have been compared with those of the classical fuzzy PID controller without a …

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A Survey On The H.264/Avc Standard, Nükhet Özbek, Turhan Tunali Jan 2005

A Survey On The H.264/Avc Standard, Nükhet Özbek, Turhan Tunali

Turkish Journal of Electrical Engineering and Computer Sciences

H.264/AVC is a recently completed video compression standard jointly developed by ITU-T VCEG and ISO/IEC MPEG standards committees. The standard is becoming more popular as it promises much higher compression than that possible with earlier standards. The standard provides flexibilities in coding and organization of data which enable efficient error resilience. The increased coding efficiency offers new application areas and business opportunities. As might be expected, the increases in compression efficiency and flexibility come at the expense of increase in complexity, which is a fact that must be overcome. This paper provides an overview of the technical features of H.264 …

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Control Charts Approach For Scenario Recognition In Video Sequences, Ersi̇n Elbaşi, Long Zuo, Kishan Mehrotra, Chilukuri Mohan, Pramod Varshney Jan 2005

Control Charts Approach For Scenario Recognition In Video Sequences, Ersi̇n Elbaşi, Long Zuo, Kishan Mehrotra, Chilukuri Mohan, Pramod Varshney

Turkish Journal of Electrical Engineering and Computer Sciences

A new approach, based on control charts, is presented for the task of recognition of events and scenarios in video image sequences. For each image in the sequence, low level image processing and feature extraction steps result in feature descriptors for objects of interest detected in the images. Control charts analysis is then explored to classify the nature of the activity depicted by the temporal changes in these features over the image sequence. Scenario recognition with higher accuracy is achieved using this simple approach.

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A Model For User Profiling Systems With Interacting Agents, Sanem Sariel, Tevfi̇k Akgün Jan 2005

A Model For User Profiling Systems With Interacting Agents, Sanem Sariel, Tevfi̇k Akgün

Turkish Journal of Electrical Engineering and Computer Sciences

Service systems according to users' personal demands and preferences are on their way to provide required services in many application domains. Emulation of interactive model of human societies produces valuable outcomes for such systems. In this work, a system model with interactive agents for multi user service systems is proposed. A novel social interactive agent model using different interaction forms is also included in this proposal. In this model, agents decide how to serve to their users by considering their users' profiles and information from other agents. User clusters are formed by clustering techniques. The Q-learning algorithm is used for …

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Bio-Inspired Approaches For Critical Infrastructure Protection: Application Of Clonal Selection Principle For Intrusion Detection And Facts Placement, Kasthurirangan Parthasarathy Jan 2005

Bio-Inspired Approaches For Critical Infrastructure Protection: Application Of Clonal Selection Principle For Intrusion Detection And Facts Placement, Kasthurirangan Parthasarathy

Masters Theses

"In this research, Clonal Selection, an immune system inspired approach, is utilized along with Evolutionary Algorithms to solve complex engineering problems such as Intrusion Detection and optimization of Flexible AC Transmission System (FACTS) device placement in a power grid. The clonal selection principle increases the strength of good solutions and alters their properties to find better solutions in a problem space. A special class of evolutionary algorithms that utilizes the clonal selection principle to guide its heuristic search process is termed Clonal EA. Clonal EAs can be used to solve complex pattern recognition and function optimization problems, which involve searching …

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Rcu Semantics: A First Attempt, Paul E. Mckenney, Jonathan Walpole Jan 2005

Rcu Semantics: A First Attempt, Paul E. Mckenney, Jonathan Walpole

Computer Science Faculty Publications and Presentations

There is not yet a formal statement of RCU (read-copy update) semantics. While this lack has thus far not been an impediment to adoption and use of RCU, it is quite possible that formal semantics would point the way towards tools that automatically validate uses of RCU or that permit RCU algorithms to be automatically generated by a parallel compiler. This paper is a first attempt to supply a formal definition of RCU. Or at least a semi-formal definition: although RCU does not yet wear a tux (though it does run in Linux), at least it might yet wear some …

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An Empirical Study Of Imputation Techniques For Software Data Sets, Sumanth Yenduri Jan 2005

An Empirical Study Of Imputation Techniques For Software Data Sets, Sumanth Yenduri

LSU Doctoral Dissertations

Software Project Effort/Cost/Time Estimation has been one of the hot topics of research in the current software engineering industry. Solutions for effort/cost/time estimation are in great demand. Knowledge of accurate effort/cost/time estimates early in the software project life cycle enables project managers manage and exploit resources efficiently. The constraints of cost and time can also be met. To this day, most companies rely on their historical database of past project data sets to predict estimates for future projects. Like other data sets, software project data sets also suffer from numerous problems. The most important problem is they contain missing/incomplete data. …

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Efficient Automatic Correction And Segmentation Based 3d Visualization Of Magnetic Resonance Images, Mikhail V. Milchenko Jan 2005

Efficient Automatic Correction And Segmentation Based 3d Visualization Of Magnetic Resonance Images, Mikhail V. Milchenko

LSU Doctoral Dissertations

In the recent years, the demand for automated processing techniques for digital medical image volumes has increased substantially. Existing algorithms, however, still often require manual interaction, and newly developed automated techniques are often intended for a narrow segment of processing needs. The goal of this research was to develop algorithms suitable for fast and effective correction and advanced visualization of digital MR image volumes with minimal human operator interaction. This research has resulted in a number of techniques for automated processing of MR image volumes, including a novel MR inhomogeneity correction algorithm derivative surface fitting (dsf), automatic tissue detection algorithm …

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Broadcast In Sparse Conversion Optical Networks Using Fewest Converters, Tong Yi Jan 2005

Broadcast In Sparse Conversion Optical Networks Using Fewest Converters, Tong Yi

LSU Doctoral Dissertations

Wavelengths and converters are shared by communication requests in optical networks. When a message goes through a node without a converter, the outgoing wavelength must be the same as the incoming one. This constraint can be removed if the node uses a converter. Hence, the usage of converters increases the utilization of wavelengths and allows more communication requests to succeed. Since converters are expensive, we consider sparse conversion networks, where only some specified nodes have converters. Moreover, since the usage of converters induces delays, we should minimize the use of available converters. The Converters Usage Problem (CUP) is to use …

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Biologically Inspired Learning System, Patrick Mcdowell Jan 2005

Biologically Inspired Learning System, Patrick Mcdowell

LSU Doctoral Dissertations

Learning Systems used on robots require either a-priori knowledge in the form of models, rules of thumb or databases or require that robot to physically execute multitudes of trial solutions. The first requirement limits the robot’s ability to operate in unstructured changing environments, and the second limits the robot’s service life and resources. In this research a generalized approach to learning was developed through a series of algorithms that can be used for construction of behaviors that are able to cope with unstructured environments through adaptation of both internal parameters and system structure as a result of a goal based …

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Medical Image Enhancement, Alina Monica Trifas Jan 2005

Medical Image Enhancement, Alina Monica Trifas

LSU Doctoral Dissertations

Each image acquired from a medical imaging system is often part of a two-dimensional (2-D) image set whose total presents a three-dimensional (3-D) object for diagnosis. Unfortunately, sometimes these images are of poor quality. These distortions cause an inadequate object-of-interest presentation, which can result in inaccurate image analysis. Blurring is considered a serious problem. Therefore, “deblurring” an image to obtain better quality is an important issue in medical image processing. In our research, the image is initially decomposed. Contrast improvement is achieved by modifying the coefficients obtained from the decomposed image. Small coefficient values represent subtle details and are amplified …

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Automatic Segmentation Of Magnetic Resonance Images Of The Brain, Kirk V. N. Spence Jan 2005

Automatic Segmentation Of Magnetic Resonance Images Of The Brain, Kirk V. N. Spence

LSU Doctoral Dissertations

Magnetic resonance imaging (MRI) is a technique used primarily in medical settings to produce high quality images of the human body’s internal anatomy. Each image is of a thin slice through the body, with the typical distance between slices being a few millimeters. Brain segmentation is the delineation of one or more anatomical structures within images of the brain. It promotes greater understanding of spatial relationships to aid in such tasks as surgical planning and clinical diagnoses, particularly when the segmented outlines from each image slice are displayed together as a surface in three-dimensions. A review of the literature indicates …

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Adaptive Remote Visualization System With Optimized Network Performance For Large Scale Scientific Data, Mengxia Zhu Jan 2005

Adaptive Remote Visualization System With Optimized Network Performance For Large Scale Scientific Data, Mengxia Zhu

LSU Doctoral Dissertations

This dissertation discusses algorithmic and implementation aspects of an automatically configurable remote visualization system, which optimally decomposes and adaptively maps the visualization pipeline to a wide-area network. The first node typically serves as a data server that generates or stores raw data sets and a remote client resides on the last node equipped with a display device ranging from a personal desktop to a powerwall. Intermediate nodes can be located anywhere on the network and often include workstations, clusters, or custom rendering engines. We employ a regression model-based network daemon to estimate the effective bandwidth and minimal delay of a …

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Learning Discrete Hidden Markov Models From State Distribution Vectors, Luis G. Moscovich Jan 2005

Learning Discrete Hidden Markov Models From State Distribution Vectors, Luis G. Moscovich

LSU Doctoral Dissertations

Hidden Markov Models (HMMs) are probabilistic models that have been widely applied to a number of fields since their inception in the late 1960’s. Computational Biology, Image Processing, and Signal Processing, are but a few of the application areas of HMMs. In this dissertation, we develop several new efficient learning algorithms for learning HMM parameters. First, we propose a new polynomial-time algorithm for supervised learning of the parameters of a first order HMM from a state probability distribution (SD) oracle. The SD oracle provides the learner with the state distribution vector corresponding to a query string. We prove the correctness …

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Radio Resource Management For Cellular Wireless Local Area Networks., Olivia Brickley Jan 2005

Radio Resource Management For Cellular Wireless Local Area Networks., Olivia Brickley

Theses

The growing demand for mobile computing worldwide has led to the increasing deployment and use of Wireless Local Area Networks (WLANs) in the last number of years. During this time, user requirements have evolved, resulting in a more diverse mix of services being carried over the wireless medium. In particular, delay sensitive real-time applications such as streaming multimedia and voice over IP are growing in importance. The widely accepted IEEE 802.11b standard, however, was not designed with sufficient Quality of Service (QoS) constraints for such applications. A new draft of the standard named 802.1 le has been proposed that deals …

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Opto-Vlsi Processing For Reconfigurable Optical Devices, Chung-Kiak Poh Jan 2005

Opto-Vlsi Processing For Reconfigurable Optical Devices, Chung-Kiak Poh

Theses: Doctorates and Masters

The implementation of Wavelength Division Multiplexing system (WDM) optical fibre transmission systems has the potential to realise this high capacity data rate exceeding 10 Tb/s. The ability to reconfigure optical networks is a desirable attribute for future metro applications where light paths can be set up or taken down dynamically as required in the network. The use of microelectronics in conjunction with photonics enables intelligence to be added to the high-speed capability of photonics, thus realising reconfigurable optical devices which can revolutionise optical telecommunications and many more application areas. In this thesis, we investigate and demonstrate the capability of Opto-VLSI …

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The Pedagogical And Practical Issues Of Using Ict In Post-Primary Schools, Kay O'Sullivan Mc Carty Jan 2005

The Pedagogical And Practical Issues Of Using Ict In Post-Primary Schools, Kay O'Sullivan Mc Carty

Theses

This study was an investigation into some of the pedagogical and practical issues that need to be considered when using ICT, with particular reference to post-primary schools. This investigation was prompted by the introduction of broadband into Irish schools in the next twelve months. Resources need to be developed that are subject specific and relevant to the Irish curriculum. The principle learning theories were examined and their pedagogical implications for post-primary teachers were discussed. The definition of learning styles was explored, different measurements were looked at and several internet based inventories were examined. The VARK questionnaire was administered to a …

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A Context-Dependent Model Of Proximity In Physically Situated Environments, John D. Kelleher, Geert-Jan M. Kruijff Jan 2005

A Context-Dependent Model Of Proximity In Physically Situated Environments, John D. Kelleher, Geert-Jan M. Kruijff

Conference papers

The paper presents a computational model for a context-dependent analysis of a physical environment in terms of spatial proximity. The model provides a basis for grounding linguistic analyses of spatial expressions in visual perception. The model uses potential fields to model spatial proximity. It has been implemented, and when combined with a handcrafted grammar, is used to enable a conversational robot to carry out a situated dialogue with a human. The key concept in our approach is defining the region that is proximal to a landmark based on the spatial configuration of other objects in the scene. The model extends …

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Maintaining The Identity Of Dynamically Embodied Agents, Alan Martin, Gregory O'Hare, Brian Duffy, Bianca Schoen-Phelan, John Bradley Jan 2005

Maintaining The Identity Of Dynamically Embodied Agents, Alan Martin, Gregory O'Hare, Brian Duffy, Bianca Schoen-Phelan, John Bradley

Conference papers

Virtual agents are traditionally constrained in their embod- iment, as they are restricted to one form of body. We propose allowing them to change their embodiment in order to expand their capabili- ties. This presents users with a number of di±culties in maintaining the identity of the agents, but these can be overcome by using identity cues, certain features that remain constant across embodiment forms. This pa- per outlines an experiment that examines these identity cues, and shows that they can be used to help address this identity problem.

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Intentional Embodied Agents, Alan Martin, Gregory M.P. O'Hare, Brian R. Duffy, John F. Bradley, Bianca Schoen-Phelan Jan 2005

Intentional Embodied Agents, Alan Martin, Gregory M.P. O'Hare, Brian R. Duffy, John F. Bradley, Bianca Schoen-Phelan

Conference papers

The notion of embodiment within a virtual environment and an intelligent agent could be intimately linked, in order to form a single Agent Chameleon. This paper presents an architecture for achieving this, while allowing agents freedom to chose an embodiment suitable to the task at hand..

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The Amphere Algorithm: Area Masking With The Performance Equation, Bianca Schoen-Phelan, Gregory O'Hare, Brian Duffy, Alan Martin, John Bradley Jan 2005

The Amphere Algorithm: Area Masking With The Performance Equation, Bianca Schoen-Phelan, Gregory O'Hare, Brian Duffy, Alan Martin, John Bradley

Conference papers

This paper is concerned with the employment of an autonomous and intelligent agent within the context of a 3-dimensional virtual environment. As the agent is immersed within the virtual environment, it empowers the 3D world with mechanisms to adjust itself to the specific needs of its user. Therefore, the agent serves as a middle layer between user and the environment. The 3-dimensional environment thus evolved into an intelligent user interface. We track user’s motion within this environment and present an equation upon which the agent classifies the user’s performance. Based upon this performance value, the agent autonomously determines if the …

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Bi-Directional Ontology Versioning Bov, Siyang Zhao, Brendan Tierney Jan 2005

Bi-Directional Ontology Versioning Bov, Siyang Zhao, Brendan Tierney

Conference papers

his paper defines a new type of ontology versioning: Bi-directional Ontology Versioning: BOV. BOV provides bi-directional mappings and transformations between concepts in two ontology versions. BOV is identified by two levels mapping processes: linguistic mapping and structural mapping. BOV can satisfy the requirement of mapping in distributed environment.

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Protecting The Communication Structure In Sensor Networks, S. Olariu, Q. Xu, M. Eltoweissy, A. Wadaa Jan 2005

Protecting The Communication Structure In Sensor Networks, S. Olariu, Q. Xu, M. Eltoweissy, A. Wadaa

Computer Science Faculty Publications

In the near future wireless sensor networks will be employed in a wide variety of applications establishing ubiquitous networks that will pervade society. The inherent vulnerability of these massively deployed networks to a multitude of threats, including physical tampering with nodes exacerbates concerns about privacy and security. For example, denial of service attacks (DoS) that compromise or disrupt communications or target nodes serving key roles in the network, e.g. sink nodes, can easily undermine the functionality as well as the performance delivered by the network. Particularly vulnerable are the components of the communications or operation infrastructure. Although, by construction, most …

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