SATNAC 2009 Conference Papers
Work in Progress – Oral Presentations
Authors: Muhammad Abdullah
Abstract: The century-old power grids do not meet many of the requirements of modern economies. The invisibility of the details of electricity consumption is the prime cause behind much of the wastage of domestic electricity. Utilities are also not able to log detailed information about the consumption patterns of each of their electricity consumers. Direct feedback has proven to be effective. This paper proposes a system that can be used as a way of reducing the consumption and wastage of electricity. The solution proposed is to use cell phones or other handheld devices as a tool to both display information and allow consumers to control appliances in their homes. The paper presents a concept that is still to be implemented and tested.
Authors: Etienne Ackermann (
Abstract: The accurate determination of the electron density profile for sections of the ionosphere is of critical importance in a number of scientific and engineering applications, including high frequency (HF) direction finding and navigation. The ionospheric total electron content (TEC) can be derived from dual frequency global positioning satellite (GPS) signals, which may then be used to estimate the electron density profiles through tomographic inversion. This inverse formulation is ill-posed; and leads to an extremely ill-conditioned operator matrix after discretization. This operator matrix is also expected to be highly rank deficient. We will attempt to uniquely reconstruct the electron density distribution by applying nonlinear numerical Bayesian estimation methods such as Gaussian Processes (GP) to the highly multimodal problem.
Authors: Jameel Adam (
Abstract: The SASL
project at the University of the
Authors: Akinlawon Amoo (
Abstract: Hydrogen which is the major fuel employed in fuel cells can be generated from various sources. Its production from fossil fuels such as coal or natural gas has negative environmental impacts like greenhouse effects, air pollution, and ozone layer depletion. It is therefore imperative to find an alternative and environmentally friendly means of generating hydrogen for fuel cells. For these reasons, research and design is being focused on the generation of hydrogen from renewable such as solar and wind. This paper presents work in progress for research on the solar-photovoltaic generation of hydrogen.
Authors: Frans Böning (
Abstract: This document proposes research on the arrangement of nodes in wireless networks containing network coding suitable topologies. Optimal node placement as well as the boundaries of topologies will be identified. Simulation and implementation of the resulting topologies will follow. The obtained knowledge can be used during the practical implementation of network coding in wireless networks.
Authors: Innocentia Dlamini (
Abstract: Network forensics involves capturing, recording and analyzing network activity in discovering the source of security policy violations or information assurance. The network forensic system that is described in this paper is called "Catch-it-as-you-can" system, which seizes all packets passing through certain traffic point, captures and writes them to the storage. The main aim of this paper is to address some of the Logical Traffic Isolation (LTI) model challenges, more specifically the incompleteness of evidence gathering process. This study proposes the Bidirectional Logical Traffic Isolation model (BLTI) to improve evidence completeness by recording both the request and the response of the suspicious communication; instead of the request (suspicious data) only as LTI did. The BLTI uses indexing method to improve information recording and retrieval. This research will continue with the evaluation of the BLTI model performance which is not covered in this paper.
Authors: Sabelo Dlamini (
Abstract: Next-generation wireless systems are envisioned to have an all-IP-based infrastructure with the support for heterogeneous access technologies. The design of intelligent mobility management techniques is one of the key research challenges these systems. In this paper we will outline the current challenges in FMIPv6 as a mobility management technique for next-generation wireless systems. We will analyse the solutions that have been proposed to solve these mobility management challenges. In addition, we will look at the issues that the current solutions did not address. We will then propose a cross-layer design approach utilising the IEEE 802.21 MIH services such as predictive layer 2 triggers to optimize FMIPv6.
Abstract: Different studies have proposed number of routing protocols to overcome data transmission challenges. Very few of these protocols consider node energy. In this study, the state of art work from various studies is reviewed and compared based on the some design criteria that are proposed in this paper. This paper proposes a new routing protocol that will prioritizes on energy efficiency. This protocol will be formulated using the HWMN protocol as the default protocol, together with other two protocols that has better characteristics on the other criteria. The formulated protocol is hoped to assist in saving energy in the WMN.
Authors: Gerhard du Plessis (
Abstract: Wireless Sensor Networks (WSN) are used more and more in modern day applications that involve wireless communication and the monitoring and/or control of an environmental parameter. In this paper the development of a modular wireless network node, based upon the systems engineering approach, is discussed. This new node will use the IEEE 802.15.4 protocol as basic communication method. A comparison between a proprietary routing protocol and the ZigBee standard will also be made during the development of the new node.
Authors: Mark Evans (
Abstract: Due to the ongoing development of low cost computational power it is now plausible to execute image processing techniques on modern workstations. New advances in video processing algorithms provide methods for computer vision functions to be applied in general applications. One useful function is object tracking. The use of visual tracking to follow hand gestures for a user interface is plausible with the use of a common graphics processing unit (GPU). This work in progress explores the components and factors required to implement a visual target tracking system.
Authors: Takayedzwa Gavaza (
Abstract: The digital divide is a term often used to describe differences between rich and poor communities. This term however is more encompassing than that, as it relates to the divide between those who have access to information and communication technologies (ICTs) and those who don’t. Since their appearance in the early 1980s, Graphical User Interfaces (GUIs) have become the standard paradigm for human computer interaction . Although their name suggests a move away from text, GUIs are designed primarily for use by literate users, with their reliance on text across all interface components, including icons, menu options and buttons. This heavy use of text on everything poses access barrier to illiterate and semi-literate users. Although there is growing interest in research focused on providing user interface (UI) alternatives for illiterate and semi-literate users, but as of yet there has been no consistent way of providing augmented UIs to bridge this digital divide. This paper describes an investigation into UIs to develop an augmented user interface (AUI) that can be used by illiterate and semi-literate users. The main objective is to develop a standard toolkit and a set of guidelines that can be used by developers to design UIs such that even novice, illiterate users require no intervention to use them.
Authors: Hannes Goosen (
Abstract: With the rapid growth of internet users and e-commerce in the past few years, spam has become an even bigger problem. Consequently, for Internet Service Providers, it has become more important to identify and filter spam efficiently in order to keep their client base satisfied. Gen-eralized Additive Neural Networks (GANNs) have proven to be a good method for pattern recognition and can be used for detecting spam messages. In this paper, GANNs are discussed and applied to a spam dataset to determine their predictive accuracy. Compared to other techniques found in the literature, GANNs perform favourably and may be used to increase the accuracy by which spam are detected.
Authors: Doron Horwitz (
Abstract: The current approach to services in the Next Generation Network can be overly complex. The interfaces into the service signalling are tied to the technology of the underlying core network. To simplify the development of modern multimedia services, direct application layer signalling in proposed. This results in the focus of service development being moved into the application layer and the service environment being better structured with abstracted, object-oriented and technology neutral APIs which cater well for IT software developers. The locus of bearer connectivity control is also moved into the service layer to centralise control of multimedia sessions. These changes to the current approach to service development result in a robust efficient framework for modern telecommunication services creation.
Authors: Sarah Kabahuma (
Abstract: Heterogeneous networks are the next generation of wireless networks. They are envisioned to offer high data rates and multimedia services. Additionally, they are intended to offer services to users regardless of the access technology. Provision of multimedia services to users will result in high demand for radio resources, which are scarce. It is therefore important to manage radio resources effectively so as to meet users’ QoS requirements. Call admission control has been used in heterogeneous networks to ensure efficient utilisation by determining how resources are allocated. However variation in users’ demand for services with time and across individual networks can cause traffic imbalance and poor QoS in heterogeneous wireless networks. Pricing can be used with admission control to improve the effectiveness of admission control. Pricing affects the behaviour of users, and therefore can be used for QoS provisioning in heterogeneous wireless networks. However pricing also affects network operators’ revenues. This research is intended to determine what revenues are obtainable for network operators when pricing is incorporated with admission control for QoS provisioning in heterogeneous wireless networks. This will be achieved by analysing pricing in admission control in heterogeneous wireless networks, and comparing different pricing scenarios; flat and dynamic pricing.
Authors: Conraad Maree (
Abstract: Wireless networks are becoming more popular and many network users prefer wireless infrastructure above the wired infrastructure because wireless networks are easy to install, maintain and use. One problem however, is that the network model used to develop protocols for the wireless network is the same layered model used for wired networks. This paper proposes research on cross-layer protocols which will improve the performance of wireless networks. The Open Systems Interconnected (OSI) model will be studied to determine candidate layers for cross-layer interaction and existing cross-layer protocols will be evaluated and considered for the development of a cross-layer protocol which will improve the performance of a wireless adhoc network.
Authors: Martin Mhlanga (
Abstract: The IEEE 802.11s working group has commenced activities, which would lead to the development of a standard for wireless mesh networks (WMNs). The draft of 802.11s introduces a new path selection metric called airtime link metric. However, there are various types of restrictions. The biggest restriction is the confined energy of the batteries. Thus, energy consumption is crucial in the design of new mesh routing protocols. To design such protocols, we have to look away from the traditional minimum hop routing schemes. This paper presents an energy-aware routing metric for HWMP to balance the energy consumption among the nodes of the network.
Moyo (University of
Abstract: Instant Messaging (IM) and Presence are some of the technologies that fast making their ways into corporate settings. Their growth could be attributed to the immediacy with which they enhance communication between two or more present entities. Currently there are many IM and Presence clients on the market, each of them implementing its own protocol which are mostly company confidential and hardly communicate with a different protocol. Open Mobile Alliance was created to address this problem by providing interoperable service enablers working across different platforms and operators. This work seeks to build a presence system using an open protocol, XMPP (Extensible Messaging and Presence Protocol).
Authors: Vitalis Musara (
Abstract: Polarization mode dispersion (PMD) contributions along the fibre length have been measured qualitatively and quantitatively through the backscattering polarization optical time domain reflectometry technique (P-OTDR). In this paper, we use the forward propagation state of polarization (SOP) monitoring technique to detect the dominance of PMD contributions by a fibre segment situated along a buried fibre network system. This technique is cost effective in design (unlike the P-OTDR) but does not provide information on the exact location of the dominant PMD fibre segment along the fibre link length; rather, it gives a clue about its presence. Results show a reduction in the range of the output SOP spread with an increase in the PMD of the high PMD (HiPMD) segment till it becomes uniform at ~ 0.4o i.e. when the digital delay line (the HiPMD segment) is greater than 35 ps. This means the output SOPs over the entire wavelength scan only populate a smaller portion (a spot) on the Poincaré sphere.
Authors: Joyce Mwangama (University of Cape Town), Neco Ventura (University of Cape Town)
Abstract: This paper seeks to discusses work in progress to implement a preliminary mock-up of a Deaf-to-hearing communication aid on a mobile phone. The goal is to ease communication between a Deaf and hearing users with interpreted communication between sign language and English on a mobile platform. The mock-up is meant to help a Deaf person convey medical conditions to a doctor face-to-face in the office. The user interface has pre-recorded sign language videos for the Deaf user, and English text for the doctor. This paper introduces the background of the project and briefly discusses related technology. Results from a preliminary trial of the PC-based mock-up with actual Deaf users are reported and discussed. Finally mapped out is a way to implement the communication aid system on a mobile device in a context free manner, allowing the plug and play of more communication scenarios.
Authors: Sinini Ncube (
Abstract: Zoonotic diseases are infectious diseases that are transmitted from
animals to humans or vice versa. Zoonotic disease outbreaks are a constant
threat primarily to the health, but also to the economy of any country. These
outbreaks are typically amplified in developing countries where there are poor
surveillance systems, a lack of timely communication, and poor epidemiological
knowledge . The rapid developmentof Information and Communication
Technologies (ICTs) presents an opportunity to improve the effectiveness of the
national surveillance and preparedness programs in
Authors: Siphamandla Nxumalo (
Abstract: A routing metric is a measure used by a routing protocol to select a best path, without a routing metric a protocol will not know which path to use to send a packet. A number of routing metrics exist for WMN, but routing still remains a problem for WMN. The routing metrics have not been compared with QoS parameters. This paper is a work in progress of our project in which we want to compare the performance of different routing metrics in WMN using a wireless test bed. We selected four routing metrics to be evaluated. Evaluation will reveal the best routing metric for WMN, if there is none, it will help us recommend design criteria for an optimal routing metric for WMN.
Authors: Jide Popoola (
Abstract: This paper presents a work in progress on adaptive cognitive radio system. The paper discusses an approach towards the sensing and detection of primary radio signals using modulation identification technique. Cognitive radio is visualized and realized as an intelligent software package simply referred to as a cognitive engine. In carrying out this work, cognitive radio engine will be developed using universal software radio peripheral (USRP), GNU radio and artificial neural network (ANN). The USRP and GNU radio will be used to develop the software defined radio (SDR) that will be coupled with ANN for the development of the desired cognitive radio engine that can sense the presence of primary radio signal through its ability to classify different modulation techniques.
Authors: Adeola Poroye (
Abstract: This paper presents work in progress to explore the utility of Near Field Communication technology to secure mobile financial services. The objective is to evaluate the potential of this approach as an upcoming technology for mobile cash transactions. The paper argues that Near Field Communication technology offers a feasible solution and can be integrated into a standard cellular handset to turn it into a contactless smart card. The motivation is to create a new secure way for the unbanked to perform financial transactions. A prototype has been developed and tested with participants in a laboratory environment. This paper also reports on preliminary results.
Authors: Jimmy Samalenge (University of
Abstract: The existence of web services has contributed a lot in improving the ability to exchange and use information over the internet. It has also contributed a lot in the socio-economical development of humanity especially in urban communities. This paper discusses the deployment of web services for rural communities, as one of the Information and Communication Technologies (ICTs) benefits. It also describes the early stage of the development of a localized robust system for personal communication synchronous and asynchronous through the use of web services technologies. This system will be deployed and tested in Dwesa, a rural community in the Eastern Cape Province of South Africa which already has embraced ICTs through a project called the Siyakhula Living Lab.
Authors: Evan Saunders (
Abstract: Service Oriented Architecture (SOA) is a business-driven concept that is based on architecture that uses loosely coupled services and components to support the requirements of business processes and users. The primary goal of this paper is to discuss the importance of XML files in SOA. This paper investigates how XML compression can be improved to solve the issue of memory in a mobile environment, as well as to decrease the required bandwidth, storage, and processing on a mobile device.
Authors: Ryan van den Bergh (
Abstract: The existence of numerous competing mobile standards forces network operators and subscribers to either upgrade or purchase new mobile equipment whenever new standards are developed. This is an inherent weakness within the standards development methodology. The reconfigurability concept attempts to solve this problem by providing the means to implement or update multiple mobile communication standards on generic hardware platforms through the use of software. However, currently there is no existing standard that defines a generic software architecture for all radio access technologies. The purpose of this paper is propose the development of such a system. To ensure that the proposed architecture is developed correctly, a series of basic underlying principles have been identified and the tasks that still need to be completed have been identified.
van der Haar (
Abstract: In a typical video conference all the participants involved should be properly identified and authenticated in some way or the other. This prevents unauthorized and unwanted people to be part of the conference. Present existing video conferencing systems however, have problems in this area, resulting in some risks. These risks relate precisely to the lack of facilities to properly identify and authenticate participants, making it possible for unwanted/unauthorised participants to join the conference or masquerade as another participant. In this paper a new approach is discussed that can mitigate these risks, by using facial recognition as a means of authentication.
Authors: Dirk van der Merwe (
Abstract: Digital Surface Models (DSM) are widely used in the earth sciences. There are a number of methods for automatic DSM generation from satellite imagery, each of which has its own strengths and weaknesses, none of which are perfect. The generation of DSMs from satellite imagery is a computationally complex calculation and does tend to take some time to complete. In order to generate DSMs faster, an algorithm was implemented on a Graphics Processing Unit (GPU). This platform greatly improves the processing speed but does have some drawbacks; namely, algorithms has to be adapted to be usable in a stream processor environment. The GPU algorithm decreases processing time by 900% according to preliminary results.
Authors: Bradley van Tonder (
Abstract: Mobile phones have traditionally relied on keypad and touch-screen interaction. These input modalities are not well suited to browsing map-based information on mobile phones. Sensor-based interaction techniques take advantage of the intrinsic mobility of mobile devices, allowing the user to interact using natural and intuitive gestures. Device tilting and movement have been successfully used to perform panning and zooming in mobile map-based applications. Existing implementations suffer from several limitations, including a lack of controllability. In addition, logic to interpret sensor data is hard-coded into each application. This research will examine how sensor-based interaction techniques can benefit from improved feedback and adapting to users and their tasks. A framework for incorporating sensor-based interaction into mobile map-based applications will also be developed.
Authors: Denys Vera (
Abstract: Internet Protocol Television (IPTV) is receiving a lot of attention from Telcos who are looking into or have already implemented it. For IPTV to be successful they need to make the service attractive to users so that it can generate substantial revenues. Integrating IPTV with other services can achieve this. One such service is User Generated Content (UGC). This Work-in-Progress paper explains how UGC can bring in revenue to IPTV service provides. It also discusses the deployment of UGC to IPTV users and proposes an architecture that can be used.
Abstract: The routing and flow control problems in communication networks are considered in this progress report. The problem is cast into an agent/resource allocation model referred to as a computational ecology. To achieve this, data packets are considered as agents and outgoing links from nodes as resources. The report covers the basic theoretical computational ecology model as well as its application to telecommunication networks. Further work and applications of the computational ecology model are also discussed.
Authors: Yuanyuan Wang (
Abstract: This paper describes work in progress to
to provide browser-based sign language communication for Deaf users. The paper
introduces the communication requirements for a disadvantaged Deaf community in