Computer Sciences Commons^™

A Quadratic Lower Bound For Rocchio’S Similarity-Based Relevance Feedback Algorithm With A Fixed Query Updating Factor, Zhixiang Chen, Bin Fu, John P. Abraham

Computer Science Faculty Publications

Rocchio’s similarity-based relevance feedback algorithm, one of the most important query reformation methods in information retrieval, is essentially an adaptive supervised learning algorithm from examples. In practice, Rocchio’s algorithm often uses a fixed query updating factor. When this is the case, we strengthen the linear Ω(n) lower bound obtained by Chen and Zhu (Inf. Retr. 5:61–86, 2002) and prove that Rocchio’s algorithm makes Ω(k(n−k)) mistakes in searching for a collection of documents represented by a monotone disjunction of k relevant features over the n-dimensional binary vector space {0,1}n, …

Exploring Query Optimization In Programming Codes By Reducing Run-Time Execution, Venkata Krishna Suhas Nerella, Swetha Surapaneni, Sanjay Kumar Madria, Thomas Weigert

Computer Science Faculty Research & Creative Works

Object querying is an abstraction of operations over collections, whereas manual implementations are performed at low level which forces the developers to specify how a task must be done. Some object-oriented languages allow the programmers to express queries explicitly in the code, which are optimized using the query optimization techniques from the database domain. in this regard, Java Query Language has been developed that allows object querying and performs the query optimization at run-time. Therefore, only one problem is how to reduce the task of query optimization at run-time as much as possible within the Java Query Language system. in …

Semantics Centric Solutions For Application And Data Portability In Cloud Computing, Ajith Harshana Ranabahu, Amit P. Sheth

Kno.e.sis Publications

Cloud computing has become one of the key considerations both in academia and industry. Cheap, seemingly unlimited computing resources that can be allocated almost instantaneously and pay-as-you-go pricing schemes are some of the reasons for the success of Cloud computing. The Cloud computing landscape, however, is plagued by many issues hindering adoption. One such issue is vendor lock-in, forcing the Cloud users to adhere to one service provider in terms of data and application logic. Semantic Web has been an important research area that has seen significant attention from both academic and industrial researchers. One key property of Semantic Web …

A Species-Conserving Genetic Algorithm For Multimodal Optimization, Michael Scott Brown

CCAC Theses and Dissertations

The problem of multimodal functional optimization has been addressed by much research producing many different search techniques. Niche Genetic Algorithms is one area that has attempted to solve this problem. Many Niche Genetic Algorithms use some type of radius. When multiple optima occur within the radius, these algorithms have a difficult time locating them. Problems that have arbitrarily close optima create a greater problem. This paper presents a new Niche Genetic Algorithm framework called Dynamic-radius Species-conserving Genetic Algorithm. This new framework extends existing Genetic Algorithm research.

This new framework enhances an existing Niche Genetic Algorithm in two ways. As the …

Markerless Tracking Using Polar Correlation Of Camera Optical Flow, Prince Gupta

Electronic Theses and Dissertations

We present a novel, real-time, markerless vision-based tracking system, employing a rigid orthogonal configuration of two pairs of opposing cameras. Our system uses optical flow over sparse features to overcome the limitation of vision-based systems that require markers or a pre-loaded model of the physical environment. We show how opposing cameras enable cancellation of common components of optical flow leading to an efficient tracking algorithm that captures five degrees of freedom including direction of translation and angular velocity. Experiments comparing our device with an electromagnetic tracker show that its average tracking accuracy is 80% over 185 frames, and it is …

Forensic Analysis Of The Windows 7 Registry, Khawla Abdulla Alghafli, Andrew Jones, Thomas Anthony Martin

Australian Digital Forensics Conference

The recovery of digital evidence of crimes from storage media is an increasingly time consuming process as the capacity of the storage media is in a state of constant growth. It is also a difficult and complex task for the forensic investigator to analyse all of the locations in the storage media. These two factors, when combined, may result in a delay in bringing a case to court. The concept of this paper is to start the initial forensic analysis of the storage media in locations that are most likely to contain digital evidence, the Windows Registry. Consequently, the forensic …

The 2010 Personal Firewall Robustness Evaluation, Satnam Singh Bhamra

Australian Digital Forensics Conference

With the advent of cheaper Internet connections, the number of Internet connections among home users is on the rise. Generally, home users have little understanding of the security concerns associated with Internet connectivity. To protect against computer attacks, generally a home user may install a personal firewall on his/her computer. To determine the effectiveness of personal firewalls, evaluation tests were performed against the ten firewall products available to users at local electronic stores and listed on popular firewall security websites. The firewalls were tested in their default and maximum security mode. The investigation was carried out by performing a port …

Malware Forensics: Discovery Of The Intent Of Deception, Murray Brand, Craig Valli, Andrew Woodward

Australian Digital Forensics Conference

Malicious software (malware) has a wide variety of analysis avoidance techniques that it can employ to hinder forensic analysis. Although legitimate software can incorporate the same analysis avoidance techniques to provide a measure of protection against reverse engineering and to protect intellectual property, malware invariably makes much greater use of such techniques to make detailed analysis labour intensive and very time consuming. Analysis avoidance techniques are so heavily used by malware that the detection of the use of analysis avoidance techniques could be a very good indicator of the presence of malicious intent. However, there is a tendency for analysis …

Evidential Recovery In A Rfid Business System, Brian Cusack, Ar Kar Ayaw

Australian Digital Forensics Conference

Efficient stock management in the commercial retail sector is being dominated by Radio Frequency Identification (RFID) tag implementations. Research reports of the security risk of RFID tags show that breaches are likely and that forensic readiness is a requirement. In this paper a RFID tag business simulation is reported that replicates previous research reports of security breaches with the purpose of identifying potential evidence after such attacks. A Read/Write Tag was cloned and used to replicate a SQL poisoning attack on a simulated Business System. A forensic investigation was then undertaken to identify potential locations for evidential recovery. This paper …

Cyber Forensics Assurance, Glenn S. Dardick

Australian Digital Forensics Conference

As the usage of Cyber Forensics increases, so does the potential for errors in the practice of applying Cyber Forensic. Errors in opinions derived from faulty practices have resulted in grievous miscarriages of justice. However, utilizing the foundations of Information Systems Assurance and Information Quality, a solid foundation for improving the quality and effectiveness of Cyber Forensics can be derived. The foundations of Information Systems Assurance and information Quality provide a solid foundation for improving the current efforts in Cyber Forensics. With increasing computer and network systems usage as well as the increasing frequency of attacks on information systems, the …

The Science, The Technology, The Law, Ken Fowle

Australian Digital Forensics Conference

Forensic science must satisfy two needs; that of the scientific community and that of the legal profession. It is hoped that the legal and scientific outcomes should be based on one and the same thing. Science, Technology and Law depend upon the establishment of a reliable basis of fact. But in the Court it is the law that finally decides what is fact, what is opinion and what the truth should be. This paper looks at the role of the Forensic Practitioner’s requirement for understanding the science, the technology and the law. It endeavours to explain the reasons, using cases, …

Does The Use Of Mimo Technology Used By 802.11n Reduce Or Increase The Impact Of Denial Of Service Attacks?, William Pung, Andrew Woodward

Australian Digital Forensics Conference

This paper presents the results of a simulated wireless DoS attack against a 802.11g connection that uses Single Input Single Output (SISO), and an 802.11n device that utilizes MIMO. The aim of the experiment was to determine whether the impact of a denial of service attack against MIMO architecture is greater than SISO, since it is capable of receiving more(multiple) attack frames/packets within a given time frame. It was found that both devices were negatively impacted by such attacks, and that throughout was similarly affected. It was also observed that increasing the packet flood rate resulted in a corresponding and …

Towards An Automated Digital Data Forensic Model With Specific Reference To Investigation Processes, Johan Scholtz, Ajit Narayanan

Australian Digital Forensics Conference

Existing digital forensics frameworks do not provide clear guidelines for conducting digital forensics investigation. However, had a framework existed, investigations based on known procedures and processes would follow strict prescribed standardisation. This should direct investigations following a set method for comparisons; ensuring future investigation is following one standard. Digital forensics lack confirmed and tested methods; this became obvious when we consider varied interpretations of the same case by participants using different investigation methods. Previous research covered several approaches to setting a forensics framework, which are mere adaptations of previous models. We found that only a few models present a framework …

An Investigation Into The Efficacy Of Three Erasure Tools Under Windows 7, Cheng Toy Chiang, Kelvin Triton, Andrew Woodward

Australian Digital Forensics Conference

This paper examined three erasure software tools aimed at removing evidence of online and other activity, and was investigated using the Windows 7 operating system as the test platform. The tools in question were Anti- Tracks, Free Internet Eraser and Free Internet Window Washer. The findings included each of the tested software’s ability to completely erase target data on the drive. It also included examined whether the data was erased or merely the link to the data was deleted, making the file recoverable. It was found that the Anti-Tracks program did not erase any of the information targeted by the …

Applying Soft Cluster Analysis Techniques To Customer Interaction Information, Randall E. Duran, Li Zhang, Tom Hayhurst

Research Collection School Of Computing and Information Systems

The number of channels available for companies and customers to communicate with one another has increased dramatically over the past several decades. Although some market segmentation efforts utilize high-level customer interaction statistics, in-depth information regarding customers’ use of different communication channels is often ignored. Detailed customer interaction information can help companies improve the way that they market to customers by taking into consideration customers’ behaviour patterns and preferences. However, a key challenge of interpreting customer contact information is that many channels have only been in existence for a relatively short period of time, and thus, there is limited understanding and …

Motivated Learning As An Extension Of Reinforcement Learning, Janusz Starzyk, Pawel Raif, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

We have developed a unified framework to conduct computational experiments with both learning systems: Motivated learning based on Goal Creation System, and reinforcedment learning using RL Q-Learning Algorithm. Future work includes combining motivated learning to set abstract motivations and manage goals with reinforcement learning to learn proper actions. This will allow testing of motivated learning on typical reinforcement learning benchmarks with large dimensionality of the state/action spaces.

Keep It Simple With Time: A Reexamination Of Probabilistic Topic Detection Models, Qi He, Kuiyu Chang, Ee Peng Lim, Arindam Banerjee

Research Collection School Of Computing and Information Systems

Topic detection (TD) is a fundamental research issue in the Topic Detection and Tracking (TDT) community with practical implications; TD helps analysts to separate the wheat from the chaff among the thousands of incoming news streams. In this paper, we propose a simple and effective topic detection model called the temporal Discriminative Probabilistic Model (DPM), which is shown to be theoretically equivalent to the classic vector space model with feature selection and temporally discriminative weights. We compare DPM to its various probabilistic cousins, ranging from mixture models like von-Mises Fisher (vMF) to mixed membership models like Latent Dirichlet Allocation (LDA). …

Automated Interpretation Of The Tandem Mass Spectra Of Peptides Using Artificial Neural Networks, Timothy Patrick Manning

Theses

The manual interpretation of mass spectra is a complex and time consuming task. The problem of manually interpreting this data is further exacerbated by the large numbers of mass spectra which can potentially be produced in a single proteoniics experiment. This shows the need for high throughput approaches to the interpretation of mass spectra. Existing automated approaches are however error prone due to the complexity of the task. Accordingly, this thesis discusses and evaluates the application of neural networks to improving the sensitivity, specificity and robustness of current approaches to the automated interpretation of such mass spectral data.

Several neural …

Zero-Sum Two-Player Game Theoretic Formulation Of Affine Nonlinear Discrete-Time Systems Using Neural Networks, S. Mehraeen, T. Dierks, S. Jagannathan, M. L. Crow

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the nearly optimal solution for discrete-time (DT) affine nonlinear control systems in the presence of partially unknown internal system dynamics and disturbances is considered. the approach is based on successive approximate solution of the Hamilton-Jacobi-Isaacs (HJI) equation, which appears in optimal control. Successive approximation approach for updating control input and disturbance for DT nonlinear affine systems are proposed. Moreover, sufficient conditions for the convergence of the approximate HJI solution to the saddle-point are derived, and an iterative approach to approximate the HJI equation using a neural network (NN) is presented. Then, the requirement of full knowledge of …

Mahalanobis Taguchi System (Mts) As A Prognostics Tool For Rolling Element Bearing Failures, Ahmet Soylemezoglu, Sarangapani Jagannathan, Can Saygin

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel Mahalanobis-Taguchi system (MTS)-Based fault detection, isolation, and prognostics scheme is presented. the proposed data-driven scheme utilizes the Mahalanobis distance (MD)-Based fault clustering and the progression of MD values over time. MD thresholds derived from the clustering analysis are used for fault detection and isolation. When a fault is detected, the prognostics scheme, which monitors the progression of the MD values, is initiated. Then, using a linear approximation, time to failure is estimated. the performance of the scheme has been validated via experiments performed on rolling element bearings inside the spindle headstock of a microcomputer numerical …

The Impact Of Overfitting And Overgeneralization On The Classification Accuracy In Data Mining, Huy Nguyen Anh Pham

LSU Doctoral Dissertations

Current classification approaches usually do not try to achieve a balance between fitting and generalization when they infer models from training data. Such approaches ignore the possibility of different penalty costs for the false-positive, false-negative, and unclassifiable types. Thus, their performances may not be optimal or may even be coincidental. This dissertation analyzes the above issues in depth. It also proposes two new approaches called the Homogeneity-Based Algorithm (HBA) and the Convexity-Based Algorithm (CBA) to address these issues. These new approaches aim at optimally balancing the data fitting and generalization behaviors of models when some traditional classification approaches are used. …

Transmitter Optimization In Multiuser Wireless Systems With Quality Of Service Constraints, Danda B. Rawat

Electrical & Computer Engineering Theses & Dissertations

In this dissertation, transmitter adaptation for optimal resource allocation in wireless communication systems are investigated. First, a multiple access channel model is considered where many transmitters communicate with a single receiver. This scenario is a basic component of a. wireless network in which multiple users simultaneously access the resources of a wireless service provider. Adaptive algorithms for transmitter optimization to meet Quality-of-Service (QoS) requirements in a distributed manner are studied. Second, an interference channel model is considered where multiple interfering transmitter-receiver pairs co-exist such that a given transmitter communicates with its intended receiver in the presence of interference from other …

The Monetary Value Of Virtual Goods: An Exploratory Study In Mmorpgs, Qiu-Hong Wang, Viktor Mayer-Schonberger

Research Collection School Of Computing and Information Systems

This study investigates the monetary value of time spent in virtual worlds in the context of 24 most popular MMORPGs Building on classic economic theory, we approach this issue through a combination of theoretical modeling, experiment, and cross-sectional time series data analysis. Our findings suggest that intensive social networking and flatter social hierarchy structures are associated with lower monetary value of time spent in-game. Further, two opposite network effects on the monetary value of in-game time spent were observed. One is the positive network effect from the active user base, the other is the negative network effect from the intensity …

Remote Access Forensics For Vnc And Rdp On Windows Platform, Paresh Kerai

Theses : Honours

There has been a greater implementation of remote access technologies in recent years. Many organisations are adapting remote technologies such as Virtual Network Computing (VNC) and remote desktop (RDP) applications as customer support application. They use these applications to remotely configure computers and solve computer and network issues of the client on spot. Therefore, the system administrator or the desktop technician does not have to sit on the client computer physically to solve a computer issue. This increase in adaptation of remote applications is of interest to forensic investigators; this is because illegal activities can be performed over the connection. …

Delta-Sigma Subarray Beamforming For Ultrasound Imaging, Hasan Şaki̇r Bi̇lge

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, an ultrasonic digital beamformer based on subarray processing of 1-bit delta-sigma (\Delta \Sigma ) oversampled echo signals is presented. The single-bit oversampling \Delta \Sigma conversion simplifies the coherent processing in beamforming with improved timing accuracy. Subarray processing also aims to simplify the beamforming complexity, where the partial-beam sums (low-resolution beams) are acquired from small subarrays, and then these partial beams are coherently processed for producing high-resolution beams. In the \Delta \Sigma subarray beamforming, the \Delta \Sigma coded echo signals are summed over the subarray channels, and then these partial beam-sums are first \Delta \Sigma demodulated, then processed …

State Variable Distributed-Parameter Representation Of Transmission Line For Transient Simulations, Mehmet Sali̇h Mami̇ş, Asim Kaygusuz, Muhammet Köksal

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a distributed-parameter state variable approach is used to calculate transients on transmission lines based on the concept of travelling waves. The method of characteristics for lossless line is used and the state equations are derived for the system. These equations are converted to a set of difference equations using the trapezoidal rule of integration and solved in time domain using LU decomposition. Single- and multi-phase transmission lines with various linear and non-linear terminations are considered in the illustrative examples. State-space modeling of transposed lines using modal decomposition is introduced and the effects caused by lumped parameter approximation …

On Coalgebras Over Algebras, Adriana Balan, Alexander Kurz

Engineering Faculty Articles and Research

We extend Barr’s well-known characterization of the final coalgebra of a Set-endofunctor as the completion of its initial algebra to the Eilenberg-Moore category of algebras for a Set-monad M for functors arising as liftings. As an application we introduce the notion of commuting pair of endofunctors with respect to the monad M and show that under reasonable assumptions, the final coalgebra of one of the endofunctors involved can be obtained as the free algebra generated by the initial algebra of the other endofunctor.

Families Of Symmetries As Efficient Models Of Resource Binding, Vincenzo Ciancia, Alexander Kurz, Ugo Montanari

Engineering Faculty Articles and Research

Calculi that feature resource-allocating constructs (e.g. the pi-calculus or the fusion calculus) require special kinds of models. The best-known ones are presheaves and nominal sets. But named sets have the advantage of being finite in a wide range of cases where the other two are infinite. The three models are equivalent. Finiteness of named sets is strictly related to the notion of finite support in nominal sets and the corresponding presheaves. We show that named sets are generalisd by the categorical model of families, that is, free coproduct completions, indexed by symmetries, and explain how locality of interfaces gives good …

Algebraic Theories Over Nominal Sets, Alexander Kurz, Daniela Petrişan, Jiří Velebil

Engineering Faculty Articles and Research

We investigate the foundations of a theory of algebraic data types with variable binding inside classical universal algebra. In the first part, a category-theoretic study of monads over the nominal sets of Gabbay and Pitts leads us to introduce new notions of finitary based monads and uniform monads. In a second part we spell out these notions in the language of universal algebra, show how to recover the logics of Gabbay-Mathijssen and Clouston-Pitts, and apply classical results from universal algebra.

Supporting Multiple Paths To Objects In Information Hierarchies: Faceted Classification, Faceted Search, And Symbolic Links, Saverio Perugini

Computer Science Faculty Publications

We present three fundamental, interrelated approaches to support multiple access paths to each terminal object in information hierarchies: faceted classification, faceted search, and web directories with embedded symbolic links. This survey aims to demonstrate how each approach supports users who seek information from multiple perspectives. We achieve this by exploring each approach, the relationships between these approaches, including tradeoffs, and how they can be used in concert, while focusing on a core set of hypermedia elements common to all. This approach provides a foundation from which to study, understand, and synthesize applications which employ these techniques. This survey does not …