1,720,968 research outputs found
African open source digital infrastructures: evaluating the landscape
No full textICT for development, gender studies, work, and organisational psychology, as well as evaluation reports and commissioned research from international development agencies and
Improving content delivery in low-resource networks: a case study of the African Internet Ecosystem
Get PDFThe Internet is one of the most successful inventions of recent times. The COVID-19 pandemic has, once again, proven the importance of the Internet to society, and this has further demonstrated how critical it is to build networks that are resilient, accessible and inclusive. However, the Internet in many African countries is still limited by both technical and regulatory challenges. It is along these lines that this thesis proposes a series of studies, supported by empirical evidence, to better understand the challenges of content delivery in African networks. The thesis starts by providing an understanding how the Internet is being used and consumed by low-income mobile Internet users in South African townships. By means of a mixed-methods study, combining quantitative network measurements with qualitative survey data, the thesis provides some useful insights about Internet usage patterns and the underlying reasons for specific user behaviour with regards to mobile data management. The research revealed how Internet usage patterns of users in low-resource settings are restrained by the lack of access, availability of services and data cost.It also reinforced the concept of locality of interest and at the same time showing that the mainstream Internet services remain very popular. Next, the thesis investigates the impediments faced by African users to access local content and cloud-based services. This is achieved through a study on web content hosting, focusing specifically on African local news and public sector websites. It was found that 85% of local news websites are hosted outside their respective countries by foreign companies, mostly in Europe and in the US. This section revealed how a majority of Africa's local content is still hosted remotely and this has a major incident on the Quality of Experience (QoE) of users in Africa. Considering the set of challenges of content delivery in Africa, companies such as Facebook and Google have introduced alternative mechanisms to deliver content to the end-user - purportedly using bandwidth-friendly and cost-effective technologies. This thesis performs an in-depth Quality of Service (QoS) analysis of: (1) Free Basics, a “zero-rated” service from Facebook and (2) Accelerated Mobile Pages (AMP), a mobile optimisation technology by Google. The aim of both Free Basics and AMP is to reduce the cost of access and improve the QoE on mobile devices through different techniques - albeit with some caveats pertaining to net neutrality and data privacy. However, the thesis reveals that Free Basics services provide weaker network performance than their paid counterparts, which contributes to a disjointed user experience. On the other hand, Google AMP pages can reduce traditional page sizes by a factor of 8 and the results show that Page Load Time (PLT) on African networks can significantly be improved. However, both Free Basics and Google AMP introduce serious concerns with regards to net neutrality and data privacy. One way to minimise the effects of cross-continental path is to host the content as close as possible to the end-users. For this, there must exist a robust interconnection ecosystem between African networks. The thesis performs a deep-dive in both intra-country and inter-country connectivity in Africa, looking into both delays and network path by means of a longitudinal active measurement study. The latter exposes interesting topological characteristics of cross-border connectivity and provides evidence on the existence of circuitous routing and a lack of peering within African networks. The thesis reveals a series of “communities”, in which countries have built up low-delay interconnectivity, dispelling the myth that intra-delays in Africa are universally poor. Finally and taking into account the above, the thesis studies how the development of localised Internet infrastructure such as Internet Exchange Points (IXPs) and Data Centres (DCs) can help democratise access to local content. Using a simple multi-level maturity model, the thesis categorises the readiness of African countries to provide a localised Internet infrastructure. The thesis further explores the above hypothesis by estimating the effect of increasing the number of participants of an IXP on the local content activity of the country. The latter was achieved by using a fixed-effects econometric model and a positive correlation was found between the scale of an IXP and the local content activity. The thesis finally provides some key policy points on how to improve content delivery in African networks
Assessing data protection perspectives among the residents of Rumphi and Karonga in Northern Malawi regarding the use of Unmanned Aerial Vehicles (drones) for humanitarian intervention
Get PDFDrones are used by humanitarian actors to collect data which could be classified as personally identifiable information (PII) and demographically identifiable information (DII). Though said to optimise intervention, they raise significant data protection challenges. An example is transparency: how effectively are community residents informed about the data drones collect of them and their community? How may this awareness affect their desire to consent, engage related group/community data protection rights, or to allow the data collector circumvent these rights to guarantee their faster access to aid.This paper is based on two case studies: the Northern Malawi districts of Rhumpi and Karonga, earmarked as flood-risk areas and whose residents had witnessed humanitarian drone flights. The research uses qualitative analysis of focus group discussions with selected inhabitants on a series of data protection questions relating to drones. The results show that participants were mostly unaware of the high-resolution images drones take of them and their communities; their consent would hardly be valid because of their vulnerable situation, and they preferred extensive sharing of their data to attract external aid rather than engage any DII rights. This prompted the conclusion that guaranteeing responsible drone data collection and processing in humanitarian settings would rest entirely on the humanitarian organisation, with comparably little or no engagement by the local residents
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Name2Cat: A Lightweight Autonomous Systems Classifier Using Organization Names
Get PDFAbstract—The Internet’s backbone consists of Autonomous
Systems (ASes), each typically managed by a single organisation
and providing a related set of services. Accurate AS classification
is crucial for understanding various aspects of Internet
infrastructure, including network performance and the economic
behaviours of the organisations that manage them. This granular
insight is invaluable for network operators and researchers alike.
In this paper, we propose a lightweight method for classifying
ASes based solely on the names of the ASes and their owning
organisations. By employing text feature extraction techniques,
we convert these names into numerical features suitable for
machine learning models. Our approach achieves an overall
accuracy of 80%, with F1-scores ranging from 70% to 92% across six different categories. The method performs particularly well in categories with distinctive naming conventions, which aid classification while facing challenges in categories like Transit that have less distinctive naming patterns. Although our approach uses fewer categories than the 17 found in the state-of-the-art ASdb system, which relies on a mix of public and proprietary datasets to achieve accuracies between 75% and 93%, it offers a quick and resource-efficient solution for AS classification when detailed AS information is unavailable
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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