Research Articles (Computer Science)

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https://hdl.handle.net/10566/52
The research papers in this collection represent the work of several projects.

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Browsing by Subject "Africa"

Now showing 1 - 4 of 4
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    Africa 3: A continental network model to enable the African fourth industrial revolution
    (IEEE, 2020) Ajayi, Olasupo O; Bagula, Antoine B.; Maluleke, Hloniphani C.
    It is widely recognised that collaboration can help fast-track the development of countries in Africa. Leveraging on the fourth industrial revolution, Africa can achieve accelerated development in health care services, educational systems and socio-economic infrastructures. While a number of conceptual frameworks have been proposed for the African continent, many have discounted the Cloud infrastructure used for data storage and processing as well as the underlying network infrastructure upon which such frameworks would be built. This work therefore presents a continental network model for interconnecting nations in Africa through its data centres. The proposed model is based on a multilayer network engineering approach, which first groups African countries into clusters of data centers using a hybrid combination of clustering techniques; then utilizes Ant Colony Optimisation with Stench Pheromone, that is modified to support variable evaporation rates, to find ideal network path(s) across the clusters and the continent as a whole. The proposed model takes into consideration the geo-spatial location, population sizes, data centre counts and intercontinental submarine cable landings of each African country, when clustering and routing. For bench-marking purposes, the path selection algorithm was tested on both the obtained clusters and African Union’s regional clusters.
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    Evaluating energy consumption on low-end smartphones
    (2015) Om, Shree; Tucker, William David; Rey-Moreno, Carlos; Erasmus, Zenville
    The relationship between battery consumption in smartphones and the usage statistics of a phone is direct. Modern smartphones, even low-end, are equipped with multiple wireless technologies, e.g. GSM, 3G, WiFi and Bluetooth. Each of these technologies has a different energy consumption profile. A wireless mesh project in the Mankosi community in rural South Africa is about to introduce low-end smartphones onto the network. The mesh network is powered with solar-charged batteries because the community at present does not have electricity. Local residents also use these batteries to recharge cell phones at a nominal cost. Introduction of smartphones will increase the recharge frequency as phone usage will increase; thus draining a phone battery more quickly, as well as escalate recharge costs. Thus, the smartphones must be chosen and used effectively in order for batteries to last longer. Related work identifies WiFi wireless technology as the most battery efficient way of transfer when compared to GSM, 3G and Bluetooth. This research proposes experiments to further investigate energy efficiency of WiFi in low-end smartphones that we intend to use for local and breakout voice over Internet protocol (VoIP) calls and data services, on a rural wireless mesh network.
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    Investigating battery consumption in low- end smartphones: preliminary results
    (International Information Management Corporation, 2017) Om, Shree; Tucker, William David; Rey-Moreno, Carlos
    Due to lack of electricity in the rural communities of Africa, users often have to incur extra expense on recharging their mobile phones. The limited battery capacities of low-end smartphones, therefore, present a barrier to their positive integration with such communities because of their vast networking features that likely lead to their elevated usage, thus, causing faster battery depletion and in turn, escalating recharge costs. This paper presents preliminary results of ongoing investigations on battery consumptions in low-end smartphones in order to estimate their battery life under different usage scenarios, and estimate the surge in communication expense brought about from the frequent recharging. Voice call experiments over WiFi and 3G data, in different network mode combinations, were conducted using three brands of low-end smartphones. Results, compared using analysis of variance and Tukey methods for pairwise comparison, yielded Smart4Mini brand to be the least battery draining, along with Smart Kicka being second best and Galaxy Pocket Neo being least efficient. In addition, the investigations aided in building a platform for future experiments in order to precisely estimate communication costs under different usage scenarios. Dissemination of such information can assist rural users in making well-informed communication expenditure towards purchase and usage of low-end smartphones.
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    Walking and the social life of solar charging in rural Africa
    (Association for Computing Machinery, 2013) Bidwell, Nicola J.; Siya, Masbulele Jay; Marsden, Gary; Tucker, William David; Tshemese, M.; Gaven, N.; Ntlangano, Senzo; Robinson, Simon; Eglinton, Kristen Ali
    We consider practices that sustain social and physical environments beyond those dominating sustainable HCI discourse. We describe links between walking, sociality, and using resources in a case study of community-based, solar, cellphone charging in villages in South Africa’s Eastern Cape. Like 360 million rural Africans, inhabitants of these villages are poor and, like 25% and 92% of the world, respectively, do not have domestic electricity or own motor vehicles. We describe nine practices in using the charging stations we deployed. We recorded 700 people using the stations, over a year, some regularly. We suggest that the way we frame practices limits insights about them, and consider various routines in using and sharing local resources to discover relations that might also feature in charging. Specifically, walking interconnects routines in using, storing, sharing and sustaining resources, and contributes to knowing, feeling, wanting and avoiding as well as to different aspects of sociality, social order and perspectives on sustainability. Along the way, bodies acquire literacies that make certain relationalities legible. Our study shows we cannot assert what sustainable practice means a priori and, further, that detaching practices from bodies and their paths limits solutions, at least in rural Africa. Thus, we advocate a more “alongly” integrated approach to data about practices.