DCIT Lecturers' Papers

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Papers, abstracts and publications authored by staff of the Department of Computing and Information Technology, UWI St. Augustine.

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(2011-06-14) Stoeva, Stefka; Nikov, Alexander
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Automated design and drawing of graphs
(2008-11-21T15:08:19Z) Bernard, Margaret
Better Global Polynomial Approximation for Image Rectification
(2011-06-14) Ward, Christopher
When using images to locate objects, there is the problem of correcting for distortion and misalignment in the images. An elegant way of solving this problem is to generate an error correcting function that maps points in an image to their corrected locations. We generate such a function by fitting a polynomial to a set of sample points. The objective is to identify a polynomial that passes "sufficiently close" to these points with "good" approximation of intermediate points. In the past, it has been difficult to achieve good global polynomial approximation using only sample points. We report on the development of a global polynomial approximation algorithm for solving this problem.
Better Global Polynomial Approximation for Image Rectification
(2009-11-10T15:41:40Z) Ward, Christopher
When using images to locate objects, there is the problem of correcting for distortion and misalignment in the images. An elegant way of solving this problem is to generate an error correcting function that maps points in an image to their corrected locations. We generate such a function by fitting a polynomial to a set of sample points. The objective is to identify a polynomial that passes "sufficiently close" to these points with "good" approximation of intermediate points. In the past, it has been difficult to achieve good global polynomial approximation using only sample points. We report on the development of a global polynomial approximation algorithm for solving this problem.
Burrokeet
(2010-11-19T16:42:25Z) Gardler, Ross; Singh, Rajendra G.; Cummings, Thompson; Ramanan, Anil; Mohammed, Shareeda; Bernard, Margaret; Rudder, Andrew
This item relates to the development and deployment of an open-source Learning Content Management System called Burrokeet.
COMPARING A NOVEL QOS ROUTING ALGORITHM TO STANDARD
(2010-11-19T16:42:41Z) Sivakumar, Shyamala; Phillips, Bill; Robertson, William; Goodridge S., Wayne
The problem of finding QoS paths involving several combinations of network metrics is NP-complete. This motivates the use of heuristic approaches for finding feasible QoS paths. Many constraint based routing algorithms find QoSpaths by first pruning resources that do not satish the requirements of the trafic flow and then running a shortest path algorithm on the residual graph. This approach results in a QoS path that biases thefirst metric used in the search process. In addition, it can be shown that this approach may not alwaysfind the optimal path. Our research introduces a QoS routing algorithm that is based on a decision support system that is used to compute QoS paths. We demonstrate the feasibility of this approach by comparing it to standard pruning techniques.
Computational intelligence-based personalization of interactive web systems
(2011-06-14) Rambharose, Tricia; Nikov, Alexander
The main Computational Intelligence (CI) models for personalization of interactive web systems are identified as Fuzzy Systems, Genetic Algorithms, Neural Networks, Artificial Immune Systems and Swarm Intelligence which includes Particle Swarm Optimization, Ant Colony Optimization, Bee Colony Optimization and Wasp Colony Optimization. These models are reviewed and compared regarding their inception, functions, performance and application to personalization of interactive web systems. A taxonomy for personalization of interactive web systems based on CI methods is proposed. It uses two approaches to personalize web-based systems as profile generation and profile exploitation. Based on this taxonomy a general procedure and recommendations for personalization of interactive web systems are suggested. Future directions for application of CI modelling for personalization are discussed.
The Delivery and Development of an online course using Open
(2010-11-10T15:49:01Z) Bernard, Margaret; Ramnanan, Anil
In September 2005, a Computer Science course was developed using almost exclusively a number of Open Source Learning Content Management Tools. This course was delivered twice over two semesters to students at St. George’s University, Grenada. The tools that were used to develop the course were the Burrokeet LCMS which was used to develop the content and ATutor which was used to deliver the course. Throughout the development of the course a number of observations were made as to the issues involved in developing a course for online delivery such as dealing with different file formats and arranging content in a manner that would be best suited to online delivery. This paper provides an overview of the Burrokeet System and the technologies used to develop this Open Source Learning Content Management System. It gives a practical view of how an online course using Open Source Learning Content Management tools was developed and delivered.
Education in Geographic information systems usability and user-adaptivity
(2011-06-14) McAdams, Michael Andrew; Nikov, Alexander
The objective of this paper is to advance the usability and adaption for users of geographic information systems(GIS) by developing suitably trained professionals via a tailored graduate program. Human-computer interaction models are useful in analyzing the use of GIS in specific task situations.Such analysis provides a sound basis for GIS use optiomization.GIS applications,i.e., in environmental protection or urban and regional planning, require entirely different user interfaces that for those where users are experts. Building such interfaces taking into account GIS usability and adaptation to the user appears to be a promising approach.This could be achieved by careful analysis of GIS utilization and dynamic adaptation to user preferences and interests, the given task,goals and actual work context.The students should learn the usablity principles and how to apply them for designing GIS user interfaces.In addition, they should know to analyze GIS user tasks,interests, and preferences and adapt GIS user interfaces to them.This paper integrates these two complementary disciplines.Examples using ArcView illustrating GIS usability and user adaptivity are given.A MS GIS program with specification in usability and user-adaptive systems is proposed.
Emotion-Oriented eCommerce Systems
(2010-06) LEON, SIMONE; NIKOV, ALEXANDER
During recent years, the use of intelligent systems in eCommerce has increased significantly, providing a new perspective on the overall online shopping experience. The rapid growth of eCommerce has motivated many studies on the relationship between website design, company reputation, and purchase intent. Understanding emotion is important in gaining insight on how to efficiently satisfy the needs of the eCommerce customer. Emotion recognition techniques based on modern mathematical models using computational intelligence are presented. Progression within this field of study is highlighted. The requirements for designing of intelligent emotion-oriented eCommerce systems are defined. A model for simulation of intelligent emotion-oriented eCommerce systems is proposed. It is an important tool supporting the experimental study and design of emotion-oriented eCommerce systems
Error-correcting coders with variable length and non-uniform errors
(2008-11-21T15:08:36Z) Bernard, Margaret
Expert Systems with Applications
(2011-06-13) Kieu, Duc; Chang, Chin-Chen
Recently, Zhang and Wang proposed a steganographic scheme by exploiting modification direction (EMD) to embed one secret digit d in the base-(2 × n + 1) notational system into a group of n cover pixels at a time. Therefore, the hiding capacity of the EMD method is log2(2 × n + 1)/n bit per pixel (bpp). In addition, its visual quality is not optimal. To overcome the drawbacks of the EMD method, we propose a novel steganographic scheme by exploiting eight modification directions to hide several secret bits into a cover pixel pair at a time. By this way, the proposed method can achieve various hiding capacities of 1, 2, 3, 4, and 4.5 bpp and good visual qualities of 52.39, 46.75, 40.83, 34.83, and 31.70 dB, respectively. The experimental results show that the proposed method outperforms three recently published works, namely Mielikainen’s, Zhang and Wang’s, and Yang et al.’s methods.
A fuzzy backpropagation algorithm
(2011-06-14) Stoeva, Stefka; Nikov, Alexander
This paper presents an extension of the standard backpropagation algorithm (SBP). The proposed learning algorithm is based on the fuzzy integral of Sugeno and thus called fuzzy backpropagation (FBP) algorithm. Necessary and sufficient conditions for convergence of FBP algorithm for single-output networks in case of single- and multiple-training patterns are proved. A computer simulation illustrates and confirms the theoretical results. FBP algorithm shows considerably greater convergence rate compared to SBP algorithm. Other advantages of FBP algorithm are that it reaches forward to the target value without oscillations, requires no assumptions about probability distribution and independence of input data. The convergence conditions enable training by automation of weights tuning process (quasi-unsupervised learning) pointing out the interval where the target value belongs to. This supports acquisition of implicit knowledge and ensures wide application, e.g. for creation of adaptable user interfaces, assessment of products, intelligent data analysis, etc.
Heuristic Constraint-Path Routing Decision System
(IEEE Computer Society, 2005-05-18) Sivakumar, Shyamala; Phillips, William J.; Robertson, William; Goodridge, Wayne
Heuristic QoS algorithms under strict constraints perform poorly in terms of finding a path that is suitable for a user?s QoS needs - the multiple constraint path problem (MCP). Exact QoS algorithms, on the other hand, guarantee that a path satisfying user needs would be found and o..er a more realistic approach for solving the MCP problem in view of the fact that the NP-complete character of graphs are not common in real networks. This fact has driven approaches like the SAMCRA and A*prune algorithms. However, these algorithms still have very high running times relative to heuristic approaches. When QoS routing algorithms are used in online Tra..c Engineering (TE) environments it may be necessary to route thousands of traffic flows each minute. Exact algorithms simply cannot work in such environments. We propose a heuristic algorithm that is suitable for working in an online TE environment. Simulations show that this algorithm produce high success rates in terms of finding suitable constraint paths for user flows while at the same time having execution times comparable to another heuristic based algorithms.
A High Stego-image Quality Steganographic Scheme with Reversibility and High Payload Using Multiple Embedding Strategy
(2011-06-13) Kieu, Duc; Chang, Chin-Chen
Tian’s method is a breakthrough reversible data embedding scheme with high embedding capacity measured by bits per pixel (bpp) and good visual quality measured by peak signal-to-noise ratio (PSNR). However, the embedding capacity and visual quality of this method can be significantly improved. Thus, we propose a simple reversible steganographic scheme in spatial domain for digital images by using the multiple embedding strategy. The proposed method horizontally and vertically embeds one secret bit into one cover pixel pair. The experimental results show that the proposed reversible steganographic method achieves good visual quality and high embedding capacity. Specifically, with the one-layer embedding, the proposed method can obtain the embedding capacity of more than 0.5 bpp and the PSNR value greater than 54 dB for all test images. Especially, with the five-layer embedding, the proposed method has the embedding capacity of more than 2 bpp and the PSNR value higher than 52 dB for all test images. Therefore, the proposed method surpasses many existing reversible data embedding methods in terms of visual quality and embedding capacity
An Image Authentication Based on Discrete Fourier Transform
(2011-06-14) Kieu, Duc; chang, Chin-Chen
The advances of network technologies and digital devices facilitate users to exchange multimedia data over the public networks. However, this also raises significant concerns about how to protect sensitive multimedia data from being illegally copied and unauthorized modifications. Thus, this paper proposes a fragile watermarking method to detect illegitimate alterations of the watermarked data. The proposed method embeds a grayscale watermark image into a grayscale cover image in a block-by-block manner by using discrete Fourier transform. Experimental results show that the proposed method can successfully and exactly detect and localize any tampered regions of the watermarked image.
Integrating Two Artificial Intelligence Theories in a Medical Diagnosis Application
(2010-11-03T14:27:45Z) Peter, Hadrain; Goodridge, Wayne
Reasoning Systems (Inference Mechanisms) and Neural Networks are two major areas of Artificial Intelligence(AI). The use of case-based reasoning in Artificial Intelligence systems is well known. Similarly, the AI literature is replete with papers on neural networks. However, there is relatively little research in which the theories of case-based reasoning and neural networks are combined.In this paper we integrate the two theories and show how the resulting model is used in a medical diagnosis application.An implementation of our model provides a valuable prototype for medical experts and medical students alike.
INTEGRATING WEB-BASED INSTRUCTION AND CLASSROOM TEACHING:CASE STUDIES FROM THE CARIBBEAN
(2010-11-19T16:41:06Z) Cummings, Thompson; Bernard, Margaret
This paper describes an integrated instructional model for integrating web-based instruction and classroom teaching in educational institutions in the Caribbean. Two studies are presented: one, a 1-semester Computer Science course for students at university level and the other, a 2-year course in Information Technology designed for secondary school students across the Caribbean. In each case, webbased and classroom teaching are woven into each other seamlessly throughout the period of instruction to form an integrated instructional system. The studies show that the integrated approach facilitated more effective learning. At university level, teaching emphasis changed from delivery of content to one of facilitating and guiding the learning process. The lecturer’s knowledge of the subject area remained of critical importance to the learning outcome. Students took more responsibility for their own learning and for monitoring their own progress. Teaching methods at secondary schools in the Caribbean are largely traditional, classroom teaching. With the integrated approach to teaching, the learning environment more readily caters for all levels of children within a class, allowing the teacher to provide more individual attention to students. The web course design has to be specially tailored to the student age group and the school environment.
A lossless data embedding technique by joint neighboring coding
(2011-06-14) Chang, Chin-Chen; Kieu, Duc; Wen-Chuan, Wu
Information hiding methods are currently exploited by many researchers for various applications. Proposing an efficient and feasible information hiding method is valuable. This paper presents a new reversible information hiding method for vector quantization (VQ)-compressed grayscale images by using joint neighboring coding (JNC) technique. The proposed method embeds secret data by using the difference values between the current VQ-compressed index and left or upper neighboring indices. The experimental results show that the proposed method achieves the best visual quality of reconstructed images compared with the two related works. In addition, the proposed method obtains as high embedding capacity as Lin and Chang's method, followed by Yang et al.'s method. As for execution speed, Yang et al.'s method is fastest, followed by the proposed method, and then Lin and Chang's method. With respect to bit rate, the proposed method has a little higher bit rate in comparison with the two related works.
A methodology for human factors analysis in office automation systems
(2011-06-14) Nikov, Alexander; Matarazzo, Giacinto; Orlando, Antonino
A methodology for computer-aided human factors analysis in office automation systems (OAS) design and implementation process has been developed. It incorporates a fuzzy knowledge-based evaluation mechanism which is employed to aggregate data measured in scales of different type. The methodology has a high degree of flexibility which allows it to be adjusted to the individual client situation. A case study in public administration for assessing OAS introduction from users' point of view has been carried out. On the basis of the results recommendations on further implementation have been proposed. The advantages, disadvantages, and further developments are discussed

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