Anwar Vahed - Academia.edu (original) (raw)

Papers by Anwar Vahed

CSIR Science Scope, Nov 1, 2011

Climate change is no longer an academic conjecture; there is now overwhelming scientific consensu... more Climate change is no longer an academic conjecture; there is now overwhelming scientific consensus that it is happening and many agree that it may be one of the greatest threats facing the planet.

This video contains the recording of the presentation titled "Data-Intensive Research Infras... more This video contains the recording of the presentation titled "Data-Intensive Research Infrastructure for South Africa (DIRISA)" given at the Sci-GaIA User Forum & Final Conference, held on the 23th and the 24th of March 2017 at the CSIR International Convention Centre (CICC), Pretoria, South Africa. For more information about the event, please visit http://agenda.ct.infn.it/e/scigaia-final-event. For more information about the Sci-GaIA project, please visit http://www.sci-gaia.eu

Climate change poses a major threat to environmental sustainability. In Africa, sectors which fac... more Climate change poses a major threat to environmental sustainability. In Africa, sectors which face projected vulnerability include, food security, public health and water resources. A general increase in extreme weather events is also predicted and the effects thereof are beginning to be felt. In order for responsible parties and stake holders to respond to these threats, research needs to be undertaken to understand the effects of climate change. Consequently, data has to be available for such research. The rapid advance in computer technology has led to heavy reliance on digital predictive modelling and digital data dissemination which have both been leveraged in this project. We present data sets of predicted climate-change variables, over selected urban regions of the African continent from six different types of models, which constitute a novel research resource. These datasets can be used in a host of further studies on how to address effects of climate change and can help stake-holders undertake preventative measures. We further present data dissemination technologies based on web based Open Standards for easy and free access of selected datasets from the implemented models. The advantage we provide with web based methods of data access is that the user does not need to store the whole host of datasets that they require for research, but can rather query and access selected portions of the data. We provide the user with a platform to save the downloaded data in any of the selected data formats, on the fly, over web based protocols and requests. We also provide the user with the option of viewing time series of data on user selected locations dynamically without the need to save the data. The user has the ability to view datasets of projected data as maps which can be saved for future use.

Sensory data also known as Geospatial data is collected in-situ or remotely by different types of... more Sensory data also known as Geospatial data is collected in-situ or remotely by different types of sensors from different geographic locations, by different agencies and over a period of time. A vast amount of data is processed via web services. The quality of the techniques, models and algorithms applied along the processing chain in transforming sensory data critically influences the quality of the eventually derived information. In this paper we evaluate trustworthiness of the processing chain or workflow from data acquisition to knowledge discovery. We present work in progress of a theoretical multi-tier trust framework for processing chain from data acquisition to knowledge discovery in geospatial domain. Holistic trust will be computed trough a trust function that integrate take the existing trust models.

AGUFM, Dec 1, 2008

Virtual observatories mature from their original domain and become common practice for earth obse... more Virtual observatories mature from their original domain and become common practice for earth observation research and policy building. The term Virtual Observatory originally came from the astronomical research community. Here, virtual observatories provide universal access to the available astronomical data archives of space and ground-based observatories. Further on, as those virtual observatories aim at integrating heterogeneous ressources provided by a number of participating organizations, the virtual observatory acts as a coordinating entity that strives for common data analysis techniques and tools based on common standards. The Sensor Web is on its way to become one of the major virtual observatories outside of the astronomical research community. Like the original observatory that consists of a number of telescopes, each observing a specific part of the wave spectrum and with a collection of astronomical instruments, the Sensor Web provides a multi-eyes perspective on the current, past, as well as future situation of our planet and its surrounding spheres. The current view of the Sensor Web is that of a single worldwide collaborative, coherent, consistent and consolidated sensor data collection, fusion and distribution system. The Sensor Web can perform as an extensive monitoring and sensing system that provides timely, comprehensive, continuous and multi-mode observations. This technology is key to monitoring and understanding our natural environment, including key areas such as climate change, biodiversity, or natural disasters on local, regional, and global scales. The Sensor Web concept has been well established with ongoing global research and deployment of Sensor Web middleware and standards and represents the foundation layer of systems like the Global Earth Observation System of Systems (GEOSS). The Sensor Web consists of a huge variety of physical and virtual sensors as well as observational data, made available on the Internet at standardized interfaces. All data sets and sensor communication follow well-defined abstract models and corresponding encodings, mostly developed by the OGC Sensor Web Enablement initiative. Scientific progress is currently accelerated by an emerging new concept called scientific workflows, which organize and manage complex distributed computations. A scientific workflow represents and records the highly complex processes that a domain scientist typically would follow in exploration, discovery and ultimately, transformation of raw data to publishable results. The challenge is now to integrate the benefits of scientific workflows with those provided by the Sensor Web in order to leverage all resources for scientific exploration, problem solving, and knowledge generation. Scientific workflows for the Sensor Web represent the next evolutionary step towards efficient, powerful, and flexible earth observation frameworks and platforms. Those platforms support the entire process from capturing data, sharing and integrating, to requesting additional observations. Multiple sites and organizations will participate on single platforms and scientists from different countries and organizations interact and contribute to large-scale research projects. Simultaneously, the data- and information overload becomes manageable, as multiple layers of abstraction will free scientists to deal with underlying data-, processing or storage peculiarities. The vision are automated investigation and discovery mechanisms that allow scientists to pose queries to the system, which in turn would identify potentially related resources, schedules processing tasks and assembles all parts in workflows that may satisfy the query.

The paper focuses on the information technology infrastructure required for the evaluation and mo... more The paper focuses on the information technology infrastructure required for the evaluation and monitoring of risk relating to floods in South Africa. It may be argued that in the context of developing countries, flood preparedness is more valuable than the actual response to a flood disaster. The paper looks at this flood preparedness in the context of informal and semi-formal settlements. An information technology infrastructure is proposed that will allow decision makers to be alerted to possible flood high risk areas, and in so doing maximise preparedness.

Current research in modular neural networks (MNNs) have essentially two aims; to model systematic... more Current research in modular neural networks (MNNs) have essentially two aims; to model systematic methods for constructing neural networks of high complexity and secondly, to provide building blocks for hybrid symbolic- and connectionist knowledge based implementations. The principal benefit of MNNs is that it combines the desirable features of different neural network architectures while compensating for their individual weaknesses. This paper reviews several models of modular neural networks and describes a method for constructing modular neural network subroutines that facilitate easier knowledge extraction. We explore this feature and further consider the generalization abilities of network subroutines as compared with conventional neural network architectures

This video belongs to the playlist of all the recordings related to the Sci-GaIA User Forum & Fin... more This video belongs to the playlist of all the recordings related to the Sci-GaIA User Forum & Final Conference, held on the 23th and the 24th of March 2017 at the CSIR International Convention Centre (CICC), Pretoria, South Africa. For more information about the event, please visit http://agenda.ct.infn.it/e/scigaia-final-event For more information about the Sci-GaIA project, please visit http://www.sci-gaia.eu

Slides from presentations given during Galaxy Africa 2018 (Cape Town, South Africa)<br>

Presentation given by Dr Anwar Vahed at Galaxy Africa 2018 (Cape Town, South Africa)<br>

Even though open data has a number of benefits, the biggest challenge facing open data is privacy... more Even though open data has a number of benefits, the biggest challenge facing open data is privacy. Opening access to such data involves trading off privacy for utility or vice versa. Releasing the raw data allows for better engagement with the data; however, this creates privacy risks. Protecting the data limits the usefulness of the data. Therefore a balance between privacy and utility must be maintained. It therefore becomes challenging to release data while ensuring that it is useful. This paper aims to understand the limits of open data in terms of privacy. Given national regulatory requirements in South Africa to ensure data privacy such as the Protection of Personal Information (POPI) Act, appropriate measures for mitigating privacy violation are particularly relevant for the Data Intensive Research Initiative of South Africa (DIRISA), a government funded enterprise to manage and provide access to research data repositories. This paper investigates the currently existing South...

In numerous research elds, scientists are increasingly turning to e-science and specifically scie... more In numerous research elds, scientists are increasingly turning to e-science and specifically scienti c work ows as a way of improving, broadening and hastening their results. Enhanced collaboration, on-demand access to tools, data and high performance processing facilities are some of the gains to be made. Scienti c work ows are concerned with, amongst others, supporting the repeatability and provenance of experiments. Scienti c work ows have had a measure of success in the astronomy, bio-informatics, chem-informatics, geophysics and eco-informatics domains [Gil, et. al., 2007]. This paper describes our initial investigations into developing geospatial Scienti c Work ows to support researchers in exploring, integrating and visualising Earth Observation and GIS data in conjunction with other research data. We describe some of the functionalities we require in the context of three sets of research endeavour- wild re research, ood modelling and the linking of disease outbreaks to multi...

Abstract. Statistics South Africa (Stats SA) has identified the centralised storage of data and m... more Abstract. Statistics South Africa (Stats SA) has identified the centralised storage of data and metadata as a key element in improving the quality of data. This has been interpreted within the Data Management and Information Delivery (DMID) project of Stats SA, to entail a solution founded on two key technological deliverables: There would be a central metadata repository where everything required to interpret and understand the data is stored according to standard, uniform and agreed fields and formats. Secondly, a central data storage facility would consolidate disparate sources of statistical data in a standard manner, together with a set of tools for retrieval, analysis and report-generating data. Additional core enablers comprise of the identification, development and adoption of standards, and approved policies and procedures regulating data management. This factorisation of the DMID project is reflected in its current organisational structure. This paper commences with our no...

Lecture Notes in Business Information Processing

Scrum provides many benefits to organizations requiring a project management framework for comple... more Scrum provides many benefits to organizations requiring a project management framework for complex adaptive problems. Some of these benefits include improved teamwork, improved time to market, and a noticeable decrease in software defects. The primary objective of this paper is to test nineteen research hypotheses that require a quantitative analysis of the Scrum framework. In order to test these hypotheses, the findings of a survey questionnaire was used to gather response data from Scrum practitioners on their perceptions of factors affecting Scrum adoption. Exploratory factor analysis and Cronbach's alpha analysis confirmed the validity and reliability of the measuring instrument. Following these analyses, a correlation matrix was used to test the relationship strength among the different factors. The Spearman correlation analysis revealed statistically significant correlations. Multiple linear regression statistical models were developed to examine the existence of factors and constructs impacting Scrum adoption. Our findings indicate that four of the nineteen hypotheses are statistically significant. The factors Change Resistance, Sprint Management, Relative Advantage, and Complexity are shown to have a significant linear relationship to Scrum as perceived by Scrum Practitioners working within South African organizations. Future research could incorporate a larger population sample to improve the generalizability of the findings.

Climate change poses a major threat to environment al sustainability. Africa in particular, is vu... more Climate change poses a major threat to environment al sustainability. Africa in particular, is vulnerable with projected worsening food security, increased threats to public health, increased stress on surfa ce water resources and a general increase in extreme weather events. Political commi tment regarding the development of effective mitigation and adaptation strategies n eeds to be complemented by a more comprehensive understanding of the effects of climate change. However, comparatively little is known about the projected e ffects of climate change for Africa at the local scale. We present data sets of climate -change projections downscaled to a resolution of 0.5° over the African continent, and data sets downscaled further to an 8 km grid size for areas covering selected urban ce ntres in Africa. These data sets constitute a novel and unique resource for research . We describe a set of web services that provide access to aggregations of sel ected key climate-change variables de...