Computer Science and Informatics

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Open Access
3D visualization of data from groundwater flow and transport models
(University of the Free State, 2000-11) Bekker, Meintjes; Messerschmidt, H. J.; Chiang, W. H.
English: Groundwater flow and transport models produce large amounts of data, which the human brain cannot possibly grasp. Taking advantage of the natural abilities of the human vision system, 3D visualization is often the tool of choice for understanding and communicating conceptual models, verifying model input, understanding model output, explaining and communicating conclusions and recommendations, and motivating expenses. A 3D visualization tool has therefore been developed for intelligence amplification of model data. The tool is based on a groundwater modeling system (Processing MODFLOW) and makes use of the results from existing groundwater flow (MODFLOW) and transport models (MT3DMS, PHT3D and RT3D.). The Visualization Toolkit (vtk), a C++ class library for visualization was used to render 3D geohydrological objects. Realistic scenes of 3D geospatial models and 3D distributions of geohydrological properties, such as hydraulic conductivity, heads and solute concentrations, can be rendered. The advantages of 3D visualization are evident by applying the visualization tool to case studies.
Open Access
Analysis of auto-purification response of the Apies River, Gauteng, South Africa, to treated wastewater effluent
(Water Research Commission, 2016) Omole, David O.; Badejo, Adekunle A.; Ndambuki, Julius M.; Musa, Adebola G.; Kupolati, Williams K.
The assimilative capacity of water bodies is an important factor in the integrated management of surface water resources. The current study examined the auto-recovery processes of the Apies River from wastewater discharged into it from a municipal wastewater treatment facility, using a series of equations, including the modified Streeter-Phelps equation. Field data obtained include dissolved oxygen (DO), temperature, stream velocity, depth, and width. Water samples were also obtained at 10 sampling stations for the determination of biochemical oxygen demand (BOD) using standard methods. It was observed that the DO and BOD level (5.59 mg/L and 8.5 mg/L respectively) of the effluent from the wastewater treatment facility indicated better water quality than the Apies River background DO level (5.42 mg/L) and BOD level (13 mg/L). Also, at 270 m downstream of the effluent discharge point, another effluent stream (Skinnerspruit) adversely impacted on the Apies River with DO and BOD levels of 6.5 mg/L and 9.0 mg/L, respectively, compared to the Apies River background values of 6.81 mg/L and 8.0 mg/L, respectively. The stream, however, recovered well from both the background and imposed pollution sources as it had a computed positive auto-recovery factor of 1.74. Furthermore, the measured DO deficit was plotted against predicted DO deficit. The plot revealed a close match between the measured and predicted DO deficit, indicating that the model could be used for predicting DO deficit along other segments of the river. To further improve on the natural auto-recovery processes of the Apies River, it was recommended that flow along the Skinnerspruit should be enhanced by clearing the observed aquatic plants growing within the channel. Also, suspected pollution activities taking place further upstream on the Apies River should be investigated and appropriately addressed.
Open Access
Assessing a brain-computer interface by evoking the auditory cortex through binaural beat
(University of the Free State, 2013-01) Potgieter, Louwrens; De Wet, Lizette; Schall, Robert
English: Why can some people study, read books, and work while listening to music or with noise in the background while other people simply cannot? This was the question that prompted this research study. The aim of this project was to assess the impact of binaural beats on participants during the performance of a task. The participants were exposed to different binaural beats that changed the dominant brainwaves while they were engaging in the task. A braincomputer interface was used to monitor the performance of the task in which a Lego Mindstorm robot was controlled as it moved through a course. To accomplish the aim of the project, the effects of binaural tones on participants’ task performance were investigated in relation to participants’ levels of frustration, excitement, engagement, meditation and performance. Participants were monitored by means of using an Emotiv EPOC neuroheadset. Although previous studies on binaural beats have been done, most of these studies were done on Attention deficit-hyperactivity disorder (ADHD) children, with users performing everyday tasks. In these studies, time was the only metric used. The researcher collected data by means of questionnaires that were completed by the participants to obtain personal information and measure the user experience. The aspects of frustration, excitement, engagement, meditation and performance were determined using the Emotiv headset in combination with the Emotiv software development kit, Microsoft Robotics Studio and software created by the researcher. After intensive statistical analysis, the researcher found that different sound frequencies did indeed affect user performance. Sessions where no sound frequency was applied were associated with more errors and longer time durations compared with all other frequencies. It can be concluded that invoking a participant’s dominant brainwave by means of binaural tones can change his/her state of mind. This in turn can affect the long-term excitement, short-term excitement, engagement, meditation, frustration or performance of a participant while performing a task. Much remains to be learned, in particular regarding the combination of brain-computer interfaces and human-computer interaction. The possibility of new cutting-edge technologies that could provide a platform for further in-depth research is an exciting prospect.
Open Access
Assessing a brain-computer interface by evoking the auditory cortex through binaural beats
(University of the Free State, 2014-07-22) Potgieter, Louwrens; De Wet, Lizette; Schall, Robert
English: Why can some people study, read books, and work while listening to music or with noise in the background while other people simply cannot? This was the question that prompted this research study. The aim of this project was to assess the impact of binaural beats on participants during the performance of a task. The participants were exposed to different binaural beats that changed the dominant brainwaves while they were engaging in the task. A braincomputer interface was used to monitor the performance of the task in which a Lego Mindstorm robot was controlled as it moved through a course. To accomplish the aim of the project, the effects of binaural tones on participants’ task performance were investigated in relation to participants’ levels of frustration, excitement, engagement, meditation and performance. Participants were monitored by means of using an Emotiv EPOC neuroheadset. Although previous studies on binaural beats have been done, most of these studies were done on Attention deficit-hyperactivity disorder (ADHD) children, with users performing everyday tasks. In these studies, time was the only metric used. The researcher collected data by means of questionnaires that were completed by the participants to obtain personal information and measure the user experience. The aspects of frustration, excitement, engagement, meditation and performance were determined using the Emotiv headset in combination with the Emotiv software development kit, Microsoft Robotics Studio and software created by the researcher. After intensive statistical analysis, the researcher found that different sound frequencies did indeed affect user performance. Sessions where no sound frequency was applied were associated with more errors and longer time durations compared with all other frequencies. It can be concluded that invoking a participant’s dominant brainwave by means of binaural tones can change his/her state of mind. This in turn can affect the long-term excitement, short-term excitement, engagement, meditation, frustration or performance of a participant while performing a task. Much remains to be learned, in particular regarding the combination of brain-computer interfaces and human-computer interaction. The possibility of new cutting-edge technologies that could provide a platform for further in-depth research is an exciting prospect.
Open Access
Assessing the use of a Brain-Computer Interface (BCI) in mathematics education: the case of a cognitive game
(University of the Free State, 2015) Verkijika, Silas Formunyuy; De Wet, Lizette
English: South Africa currently faces a huge shortage of mathematics skills, a problem commonly referred to as the “math crisis”. Researchers in South Africa have attributed the growing “math crisis” to the lack of cognitive functions among learners. However, existing solutions to address the problem have overlooked the role of cognitive functions in improving mathematics aptitude. Moreover, even though cognitive functions have been widely established to have a significant influence on mathematics performance, there is surprisingly little research on how to enhance cognitive functions (Witt, 2011). Consequently, this study had as primary objective to explore the impact of a BCI-based mathematics educational game as a tool for facilitating the development of cognitive function that enhance mathematics skills in children. The choice of a BCI-based solution for enhancing cognitive functions stems from recent neuroscience literature that highlights the potential of BCIs as tools for enhancing cognitive functions. Existing neuroscience, psychological and mathematical education research have established a number of cognitive functions (working memory, inhibitory control, math anxiety, and number sense) that affect mathematics education. This study combined these existing paradigms with the BCI device to provide a technological solution for enhancing the basic cognitive functions that foster mathematics learning. Following these assertions, a BCI-based mathematics educational game was developed taking into account the target population (children from the ages from 9-16) and the important role of digital educational games in improving education (in this case mathematics education in particular). Using a within-subjects short-term longitudinal research design, this study established that a BCI-based mathematics educational game could be used to significantly enhance four basic cognitive functions (working memory, inhibitory control, math anxiety, and number sense). These four cognitive functions have been widely acknowledged as significant fundamental aspects of mathematics education. As such, adopting such a technological solution in South African schools can go a long way to address the current “math crises” by enabling educators and learners to address the issue of low cognitive functions. This study culminated with practical recommendations on how to address the “math crisis” in South Africa.
Open Access
AutoCal: A software application for calibrating photometric data
(Academy of Science of South Africa (ASSAf), 2016) Wium, Daniël J.; Van Soelen, Brian
We present a software application for the calibration of stellar magnitudes in the absence of standard stars. It uses an existing algorithm to match stars in the target’s field of view to catalogue entries and computes the average offset between the two sets of magnitudes using a weighted least-squares approach. This offset is used to calibrate the target’s instrumental magnitude. The software application was used to calibrate magnitudes for six Be/X-ray binary sources in the Small Magellanic Cloud and the results were compared with published results for these sources. Where comparisons were possible, our results agreed with those results within the uncertainties specified. Infrared variability was found for all six of the sources tested. The interactive outlier removal that was made possible by our software allowed for smaller uncertainties to be reported for our results.
Open Access
A comparative study on users’ responses to graphics, text and language in a word processor interface
(University of the Free State, 2006) Beelders, René Tanya; Blignaut, P. J.; McDonald, T.
English: The word processor or some form of editor-based application has become an integral tool for the many people who rely on computers on a daily basis. As such it has a wide and varied user base and must cater for a very diverse user group. Due to the heavy reliance on the word processor it is essential that it delivers pleasurable and efficient interaction to its users. Since its inception, the word processor has displayed the ability to evolve to continually exploit the increasing capabilities of technology. This study focused on furthering the improvement of the word processor usability for a subset of South African word processor users. Specifically, it concentrated on the impact of graphics, text and language on the usability of a word processor. Graphics were incorporated into the interface by means of inclusion of the icons currently found in the Microsoft Office package, which have been accepted as the industry standard, and the development of an alternative set of icons whose usability could be compared to that of the standard icons. Text was included in the interfaces in the form of menus and tooltips as well as text buttons which replaced the afore-mentioned pictorial icons and contained no graphical depiction of the associated function. The impact of language on the usability of a word processor was viewed strictly in terms of bilingual users and was achieved through translation of the text buttons, menus and tooltips into the predominant languages of the area. Comparative user testing was conducted through implementation of a scaled-down word processor application which could accommodate interchangeable interfaces and easy administration of preset tasks. Representative users were then required to complete a series of tasks on their respective pre-assigned interface, which conformed to one of the following general interface configurations: a. An interface using either set of pictorial icons and excluding both menus and tooltips, thus containing no language component. b. An interface in their first language, achieved through use of the text buttons, menus and/or tooltips. c. An English interface, where English was not their first language. A set of usability measures was identified which allowed for the effectiveness, efficiency and satisfaction of the users to be compared between the different user interface configurations. These measurements were: a. the score achieved for the test, based on a built-in difficulty index assigned to each task; b. the satisfaction experienced during interaction with the application; and c. for each task, the: i.time, ii.number of actions, iii.number of errors and iv.ratio of correct and incorrect answers Analysis of the user testing found that no particular interface configuration exhibited increased efficiency, effectiveness, learnability or satisfaction and that users were able to adapt to a changed interface with ease once they had become accustomed to the word processor environment. Therefore, the final finding of the study was that provision of an interface in a bilingual user’s first language neither significantly contributed nor detracted from the application’s usability. Similarly, neither of the pictorial icon sets nor the text buttons exhibited a significantly heightened level of usability. Therefore, none of the interface configurations could be recommended as the most usable. However, a number of recommendations concerning the usability of a word processor were proposed based on both the analysis of the tasks and observation of user interaction. Finally, based on user performance for each individual task, an icon was identified which appeared to be the best and most applicable for that function. The final recommended interface, the usability of which must still be empirically established, consisted of a combination of standard icons, alternative icons and text buttons.
Open Access
A comparative study to determine the optimum e-assessment paradigm for testing users' word processing skills
(University of the Free State, 2008) Strauss, Hermanus Johannes; Blignaut, P. J.; Du Toit, E. R.
English: In recent times, people have become more and more reliant on computers on a daily basis. As a result, the need has arisen to optimise the task-related experience in terms of time efficiency, which demands effective training in software skills. To be more specific, word processing skills are currently considered essential in any field of work and are in high demand. This study focuses on determining the optimal paradigm (methods) to assess users’ word processing skills. One of the main reasons for this research was the fact that students at the University of the Free State (UFS) reported to the computer literacy course lecturer that they were dissatisfied with the virtual, simulated MS Word software environment used to assess (e-assess) their word processing skills electronically. This existing test system (ETS) at the UFS requires students to perform certain tasks and automatically checks whether the required end-result is obtained. However, this system is based on a simulated interface with limited functionality. As a result, the relevant information on software e-assessment systems was researched and a new software skills e-assessment application developed accordingly. The aim was to develop a tool that would be able to assess students’ word processing skills in the most reliable way possible. Another aim was to find methods of stimulating the learning process during the e-assessment of word processing skills. Therefore the newly developed e-assessment system, WordAssessor, is designed to be based on the real MS Word environment. It requires students to perform certain tasks and automatically checks whether the said tasks have been correctly performed. WordAssessor allows students to explore the MS Word interface fully while being assessed. It even allows students to use trial-and-error to solve certain problems (tasks). To stimulate learning potentially further during e-assessment, WordAssessor presents students with a video solution for the questions they had incorrect, directly after the test. In order to assess the validity of the e-assessment methods employed by the WordAssessor system, comparative user testing was conducted. Students’ word processing skills were assessed as part of their advanced computer literacy course, using the ETS, the WordAssessor system and a personalised test scenario (where no e-assessment tool was used). In addition, participating students were provided with a questionnaire to determine their reaction and preference with regard to the various elements of the assessment methods. By analysing the results in detail, it was found that the results of the personalised test scenario (PT) yielded the most reliable indication of students’ true word processing skills, and could be used as a benchmark. Hereafter, the results of the WordAssessor test scenario were analysed to determine the correlation (relationship) with the results of the personalised test. The same type of correlation was performed between the results of the ETS and PT. It was established that the WordAssessor results correlated significantly more closely with the PT results than the ETS. In the end (and after additional analysis) it was found that the methods employed by WordAssessor yielded the most reliable indication of students’ true word processing skills knowledge when compared to the ETS. In addition, from the results of the post-assessment questionnaire, it was determined that students felt they learned more as a result of the video tutorials. Furthermore, they stated that they preferred video feedback over text- or paper-based feedback. They also stated that they preferred being assessed in a real software environment, as opposed to a simulation. It was recommended that a more flexible and realistic e-assessment approach (as demonstrated by the WordAssessor system) could be beneficial to students on several levels. Also, it was recommended that students be able to answer test questions in a way that suits them rather than being instructed as to the method of use. Finally, the use of highly detailed video tutorials directly following e-assessment (only for questions students had incorrect), was recommended.
Open Access
A comparative study to determine the optimum e-assessment paradigm for testing users' word processing skills
(University of the Free State, 2008) Strauss, Hermanus Johannes
English: In recent times, people have become more and more reliant on computers on a daily basis. As a result, the need has arisen to optimise the task-related experience in terms of time efficiency, which demands effective training in software skills. To be more specific, word processing skills are currently considered essential in any field of work and are in high demand. This study focuses on determining the optimal paradigm (methods) to assess users’ word processing skills. One of the main reasons for this research was the fact that students at the University of the Free State (UFS) reported to the computer literacy course lecturer that they were dissatisfied with the virtual, simulated MS Word software environment used to assess (e-assess) their word processing skills electronically. This existing test system (ETS) at the UFS requires students to perform certain tasks and automatically checks whether the required end-result is obtained. However, this system is based on a simulated interface with limited functionality. As a result, the relevant information on software e-assessment systems was researched and a new software skills e-assessment application developed accordingly. The aim was to develop a tool that would be able to assess students’ word processing skills in the most reliable way possible. Another aim was to find methods of stimulating the learning process during the e-assessment of word processing skills. Therefore the newly developed e-assessment system, WordAssessor, is designed to be based on the real MS Word environment. It requires students to perform certain tasks and automatically checks whether the said tasks have been correctly performed. WordAssessor allows students to explore the MS Word interface fully while being assessed. It even allows students to use trial-and-error to solve certain problems (tasks). To stimulate learning potentially further during e-assessment, WordAssessor presents students with a video solution for the questions they had incorrect, directly after the test. In order to assess the validity of the e-assessment methods employed by the WordAssessor system, comparative user testing was conducted. Students’ word processing skills were assessed as part of their advanced computer literacy course, using the ETS, the WordAssessor system and a personalised test scenario (where no e-assessment tool was used). In addition, participating students were provided with a questionnaire to determine their reaction and preference with regard to the various elements of the assessment methods. By analysing the results in detail, it was found that the results of the personalised test scenario (PT) yielded the most reliable indication of students’ true word processing skills, and could be used as a benchmark. Hereafter, the results of the WordAssessor test scenario were analysed to determine the correlation (relationship) with the results of the personalised test. The same type of correlation was performed between the results of the ETS and PT. It was established that the WordAssessor results correlated significantly more closely with the PT results than the ETS. In the end (and after additional analysis) it was found that the methods employed by WordAssessor yielded the most reliable indication of students’ true word processing skills knowledge when compared to the ETS. In addition, from the results of the post-assessment questionnaire, it was determined that students felt they learned more as a result of the video tutorials. Furthermore, they stated that they preferred video feedback over text- or paper-based feedback. They also stated that they preferred being assessed in a real software environment, as opposed to a simulation. It was recommended that a more flexible and realistic e-assessment approach (as demonstrated by the WordAssessor system) could be beneficial to students on several levels. Also, it was recommended that students be able to answer test questions in a way that suits them rather than being instructed as to the method of use. Finally, the use of highly detailed video tutorials directly following e-assessment (only for questions students had incorrect), was recommended.
Open Access
Comparing brain-computer interfaces across varying technology access levels
(University of the Free State, 2014) Dollman, Gavin John; De Wet, L.; Beelders, T. R.
English: A brain-computer interface (BCI) is a device that uses neurophysiological signals measured from the brain to activate external machinery. BCIs have traditionally been used to enhance the standard of living for severely disabled patients. This has resulted in a shortage of data on how BCIs perform with able-bodied individuals. There has recently (2012) been a trend towards BCI research involving able users but these studies are still too few to make a substantial impact. Additionally, traditional input methods are being replaced or supplemented by alternative natural modes of interaction and these natural interactions have become known as NUIs. To investigate the suitability of a BCI as a NUI, this study used the Emotiv headset to provide direct measurement of a participant’s performance while performing tasks similar to wheelchair manipulation in order to determine whether a participant’s access to traditional input methods influences their performance. Thus, the main aim of this study was to investigate the usability of an Emotiv for robot navigation. Additionally, the study aimed to discover whether a user’s performance differed when using a keyboard compared to the Emotiv as well as investigating whether there was improvement of performance in the short term for a user through repetitive use of the Emotiv. In order to compare the usability of the Emotiv to a keyboard the participants were placed into groups based on their exposure to traditional input methods. This was verified based on their individual expertise rating, which was a measure of frequency and length of use. The test instrument used consisted of a written program that navigated a pair of Mindstorm NXT robots across a custom designed test course. Data was collected via usability testing which measured learnability, efficiency and effectiveness. Efficiency was measured as the time taken to complete a task while effectiveness was a measure of the errors made by a participant when completing a task. Results indicated that there was no significant difference between the groups’ efficiency and effectiveness when using the Emotiv to complete a task. Thus, a user’s previous experience with a traditional input method does not influence a user’s performance with an Emotiv when navigating a robot. This result indicates that the interface is intuitive to use and, therefore the Emotiv could be suitable as a NUI. The results for the usability metrics efficiency and effectiveness indicated that there was a significant difference between the performances with the Emotiv and a keyboard. The results show that, with the Emotiv, participants took more time to complete a task and made more errors when compared to a keyboard. This discrepancy was attributed to cognitive theory as it is believed that the participants violated their preformed schema which affected their performance. However, the participants quickly became comfortable with the Emotiv which supports the evidence that the interface is intuitive to use. For neither the usability metrics efficiency nor effectiveness was a significant improvement detected with repetitive use of the Emotiv. Thus, repetitive use of the Emotiv to navigate a robot does not improve a user’s performance over a short period of time. These results indicate that in terms of efficiency and effectiveness the keyboard is the superior interface. The results also revealed that a participant’s performance is not affected by their exposure to traditional input methods when utilising a BCI. Thus, the Emotiv is intuitive to use and appears suitable for use as a NUI. This study proved that the Emotiv is an intuitive interface and can be used with little to no previous experience.
Open Access
Comparing the sensor glove and questionnaire as measures of computer anxiety
(University of the Free State, 2014-01) Nkalai, Tlholohelo Stephania; De Wet, L.
English: A vast amount of literature regarding computer anxiety exists. Consequently, a number of researchers have discovered different definitions for computer anxiety. Regardless of the numerous definitions, several researchers agree that computer anxiety involves emotional ‘fear’ or ‘apprehension’ when interacting or anticipating interaction with computers. Subsequently, some individuals who experience computer anxiety avoid using computers. This situation is undesirable because these days it is almost always a necessity for people to use computers in the workplace. It is therefore important to extensively investigate computer anxiety including measures which can be implemented to mitigate it. Different findings about computer anxiety regarding the correlates: gender, age, computer ownership, educational attainment and computer experience, exist. For example, while some research findings state that females experience higher levels of computer anxiety than males, other research findings assert that males experience computer anxiety more than the females. The contradictory findings regarding the correlates of computer anxiety could be attributed to the fact that most of the research studies which investigated computer anxiety relied solely on existing computer anxiety questionnaires. Using questionnaires exclusively poses various limitations which include relying on the ‘subjective’ responses of the participants. This research study incorporated another measurement of computer anxiety in addition to an existing computer anxiety questionnaire named Computer Anxiety Rating Scale. This additional measurement was performed using an instrument that measured physiological signals of a participant. The instrument is called an Emotion RECecognition system (EREC). It measures skin temperature and skin resistance and heart rate. Apart from the mentioned two, other data collection methods were used which are pre-test and post- test self-developed questionnaires, observations and interviews. With various measurements incorporated in this study, computer anxiety was investigated taking into consideration the following research questions:  To what extent does a sensor glove add value in measuring computer anxiety during usability testing when compared to anxiety questionnaires and observations?  To what extent is computer anxiety influenced by age, gender, computer experience, educational attainment, and ownership of a personal computer according to the anxiety questionnaire and the sensor glove? From the findings of the study in relation to the first research question, it can be concluded that the sensor glove does not add value. Instead, the sensor glove may add value when measuring stress. This means that although the EREC sensor glove measures skin conductance, changes in skin conductance may indicate changes in stress levels rather than anxiety levels. Regarding the second research question, it can be concluded that computer anxiety was not influenced by age, gender, computer experience, educational attainment, and ownership of a personal computer according to the anxiety questionnaire and the sensor glove.
Open Access
A comparison of different approaches towards a computerised information system for primary health care in the Free State
(University of the Free State, 1996-11) Blignaut, Petrus Johannes; McDonald, T.
English: This study is undertaken in the light of the current importance of the Reconstruction and Development Programme (RDP) and the SA government's commitment to better primary health care (PHC) for everybody. Primary health care services in South Africa should be rendered as effective and complete as possible with the manpower available. The government should therefore have exact knowledge about the current health situation in the country in order to make pro-active provision for better health services in the areas that need it most. Nursing management should thus have access to periodical reports regarding the incidence of epidemics, certain notifiable diseases, the death rate, general housing conditions and much more. It is therefore of the utmost importance that the service providers should capture and process statistical data accurately. This study firstly analyses the current situation with regard to data capturing, processmg, presentation and utilisation. The analysis refers to the manual system of patient carried records, tally sheets as well as the available infrastructure. Nursing management in the Free State has a long term vision to implement a database system to service all fixed and mobile clinics. A complete patient record will be kept by the system and the complete clinical history of a patient will be available at each consultation. With such a system all the regular and ad hoc reports can be processed easily and accurately. This study firstly analyses the current situation with regard to data capturing, processmg, presentation and utilisation. The analysis refers to the manual system of patient carried records, tally sheets as well as the available infrastructure. Nursing management in the Free State has a long term vision to implement a database system to service all fixed and mobile clinics. A complete patient record will be kept by the system and the complete clinical history of a patient will be available at each consultation. With such a system all the regular and ad hoc reports can be processed easily and accurately. This study focuses on the process of computerising pnmary health care services. Some theoretical background on systems analysis and development are provided and thereafter three alternative approaches towards computerisation are proposed and investigated. For each of these proposals a prototype system was developed. The first prototype is based on a patient record approach and includes a complete set of health indicators as well as other demographic and clinical data. The second prototype is based on a minimum data set that leads to more user-friendly system. Thirdly a prototype system that is not based on a patient record but on head-count-approach was developed. This system· resembles the current manual system of tally sheets. The three alternatives are compared with regard to the issues of practicality, flexibility, ease of use, accuracy and completeness of statistical reports and efficiency of time utilisation. It is concluded that the flexibility of a patient-record approach, a_lthough more time-consuming, is preferred to a head-count approach. Furthermore, the ease of use of the s~cond alternative in a developing country with mostly computer illiterate nurses makes it a much more feasible approach than a more comprehensive system. Ways in which a computerised system can be implemented in an environment with limited hardware resources are also investigated. The study concludes with a proposed model for the computerisation of primary health care in the Free State.
Open Access
A comparison of similarity metrics for e-assessment of MS Office assignments
(University of the Free State, 2015-07) Marais, Willem Sterrenberg Jacobus; Blignaut, P. J.
English: Computerised assessment is prevalent in various disciplines where immediate and accurate feedback with regard to students’ assignments is required. It is used as an alternative to manual assessment of computer programming assignments, computer proficiency tests and free-text responses to questions. The implementation of the Office Open XML (OOXML) standard, as the default document format for Microsoft Office, instigated the development of alternative computerised assessment algorithms with the ability to assess word-processing documents of the DOCX format. Word-processing assignments are primarily assessed by comparing the final document, submitted by the student, to the ideal solution provided by the examiner. Research into the anatomy of OOXML-based documents delivered several alternative approaches with regard to the computerised assessment of DOCX document types. OOXML simplifies the evaluation process of word-processing documents by providing easily identifiable elements within the document structure. These elements can then be used to assess the content and formatting of the document to determine whether the solution, submitted by the student, matches the ideal solution provided by the examiner. By examining current OOXML-based algorithms, certain gaps within the implementation thereof were identified. An alternative algorithm, dubbed the OOXML algorithm that could alleviate these issues, is introduced. It improves the assessment techniques of current OOXML-based algorithms by firstly simplifying the structure of the DOCX documents to ensure that the student’s document and examiner’s solution conform to a homogeneous structure. It then identifies corresponding paragraphs between the student’s document and the examiner’s solution. Finally, the student’s simplified document is assessed by comparing the content and formatting elements within the OOXML structure of the corresponding paragraphs with one another. To determine the accuracy and reliability of the proposed OOXML algorithm, it is compared with three established algorithms as well as manual assessment techniques. The three algorithms include a string comparison algorithm called fComp, the Levenshtein algorithm and a document difference algorithm, implemented by a system called Word Grader. The same group of word-processing assignments is graded by the specified algorithms and manually assessed by multiple human markers. Analysis of the results of a quasi-experimental study concluded that the proposed OOXML algorithm and its element comparison metric not only produced more reliable results than the human markers but also more accurate results than the human markers and the other selected document analysis algorithms.
Open Access
Determining the usability of pedagogical interface agents in the context of adult computer literacy training: a South African perspective
(University of the Free State, 2016) Mabanza, Ntima; De Wet, Lizette; Schall, Robert
𝑬𝒏𝒈𝒍𝒊𝒔𝒉 The problem of high computer illiteracy amongst adults in 3rd world countries, such as South Africa (SA), is preventing these individuals from becoming part of workforce as computer skills have become one of the major requirements to enter the job market. The other challenge for this group is that most of the current adult computer literacy training is conducted using approaches such as conventional training and e-learning. Often these approaches pose intellectual challenges to people who have never been exposed to a computer. In line with this, this research study was conducted in an effort to find new approaches to assist adult computer illiterate people, specifically in SA, to acquire the skills necessary (i.e. basic computer literacy) to promote employability and the improvement of their lives. The use of Pedagogical Interface Agents (PIAs) is one example of such a new approach. Over the years, many research studies on the potential of PIAs in promoting learning have been carried out. The results obtained from these studies showed that PIAs can improve student learning, engagement and motivation. However, most of these studies have focused on age groups ranging from childhood to undergraduate college students. Little attention has been paid to the use of PIAs in adult learning, and in computer literacy training, specifically in the word processing environment. The aim of this research study was to establish, through user testing, whether the incorporation of a variety of PIAs could improve and facilitate the computer literacy training (specifically in a word processing environment) for adult computer illiterates in SA. To achieve this aim, Simulated Microsoft Office Word System (SMOS), a simulated word processor system incorporating 10 PIAs (varying in terms of appearance, gender, voice and reality) was used in conjunction with MS Word to collect data needed for this research. A summative usability evaluation was performed in this study. The pragmatist paradigm was selected as a suitable paradigm for the current study. This research study employed the convergent parallel mixed-methods design. Study participants consisted of a group of adults from Mangaung-University of the Free State Community Partnership Programme (MUCPP) who could understand and speak English, had little or no formal education and had never been exposed to a computer before. In order to better assess the usability of the 10 PIAs incorporated in SMOS, participants were divided into two groups, namely the test group (trained with SMOS, which incorporated PIAs) and the control group (trained with MS Word, without PIAs). Afterwards, participants from both groups were given 11 basic word processing tasks to complete using their respective systems (i.e. SMOS or MS Word) as part of the user assessment. In this study, reliability and validity were established through the use of multiple sources of data, which were directly linked to the study aims and objectives. A pilot study was conducted to check the appropriateness of data collection techniques used in this study. The user test performed in this study sought to measure three usability attributes, namely efficiency (measured by means of task efforts), effectiveness (measured by means of both individual and total number of errors) and satisfaction (measured by means of the user experience questionnaire related to the amount learnt from the study overall, enjoyment in being part of the study, and willingness to participate in a similar study in future). Observations and interviews were used to complement and better understand the effectiveness, efficiency and satisfaction data. All collected user test data were analysed using comparative statistical test techniques. The comparative analyses‟ results showed that test group participants (trained with SMOS, which incorporated PIAs) outperformed the control group participants (trained with MS Word, without PIAs) in both efficiency and effectiveness. With regard to the satisfaction, no difference was noted between participants from the two groups. Based on the findings of this study, it can be inferred that the use of PIAs could assist in overcoming many problems faced by adult computer illiterate users during computer literacy training in a 3rd world environment like in SA. However, it is suggested that key aspects, such as characteristics of adult learners, PIAs‟ external observable characteristics, and adult learners‟ satisfaction/ability to use the system, need to be systematically explored. ___________________________________________________________________
Open Access
Determining the usability, user experience, and continuance use of a mobile application and an online portal: A comparative case study
(University of the Free State, 2023) Mhlongo, Thobani; De Wet, L.; Verkijika, S. F.
Background: The increasing number of users with access to the internet, computers, and mobile devices propels most institutions to avail their services through online portals and mobile applications. However, these online portals and mobile applications depend on users utilising them. There are instances where users underutilise or completely opt out of these platforms. The reasons may include poor usability and negative user experience. This is a cause for concern since funds are invested in their development with the anticipated return on investment. Aim: This study aimed to compare the usability, user experience, and continuance use of a regulatory institution's mobile application and online portal with respect to performance, user satisfaction, and continuance intentions. Methodology: This single case study followed an explanatory sequential design, wherein the initial phase consisted of data collection using a self-administered questionnaire (quantitative phase). For the second phase, the data was collected using an interview protocol (qualitative phase). The self-administered questionnaire compared the usability, user experience, and continuance use of the mobile application and the online portal. The interview protocol was used to further explain the quantitative results. Participant recruitment used systematic random sampling for the quantitative phase and purposive sampling for the qualitative phase. The analytical approach involved descriptive and inferential statistics, and thematic analysis. Findings: The results established that the online portal was more usable than the mobile application; users had a positive user experience with the online portal and were more likely to use the online portal in future, but not so much with the mobile application. The contributing factors to the online portal findings were its efficiency, user-friendliness, understandability, and learnability. In addition, inefficiency, errors, limited functionality, and lack of user-friendliness issues were identified as contributors to the mobile application's negative experience and moderate usability. Regarding continuance use, the quantitative and qualitative results suggested that participants were keen to use the online portal in the future. However, the quantitative results for the mobile application indicated that the participants did not have interest in using the mobile application again in future, despite the interview results indicating otherwise. Participants identified improvement in efficiency and visual appeal as conditions for their future re-use of the mobile application.
Open Access
The development of a virtual reality simulator for certain gastrointestinal endoscopic procedures
(University of the Free State, 1999-05) Marais, Charles Claude; Tolmie, C. J.
English: A Virtual Reality Gastrointestinal Trainer/Simulator has been developed to enable the simulation of gastrointestinal procedures on a personal computer (PC). Virtual Reality (VR) techniques are used in the construction of this computer-based system to enable the user to practice basic identification, navigational and therapeutical skills. The system consists of a computer-based simulator, a 3-dimensional (3-D) tracker, an endoscope/endocamera and a life-size gastrointestinal model. A normal endoscope/endocamera is used with a hollow transparent life-size gastrointestinal model to provide maximum realism. The computer-based simulator contains a virtual 3-D model of the relevant gastrointestinal organ. Currently the stomach, esophagus and entry to the duodenum (upper G.I. region) are focused on. The position and orientation of the front tip of the endoscope/endocamera are tracked with the 3-D tracker. This data is relayed to the computer, which then calculates and displays the appropriate image on the computer screen as realistically as possible. The calculated image closely resembles the image which would be seen with a real endoscope/endocamera in a real patient. The image is continually updated in accordance with the movement of the endoscope/endocamera and the properties of the gastrointestinal model. Some of the main problems that had to be addressed during the development of the system are: obtaining a 3-D computer graphic model of the stomach with the same shape, size, colour and texture as a real stomach; the simulation of abnormal conditions like ulcers, and how they can be placed inside the 3-D computer graphic model; the simulation of therapeutic tools, like biopsy foreceps; the implementation of realistic, but cheap force feedback; and the deforming of the 3-D computer graphic model when the user touches the inside of the stomach with the tip of the endoscope/endocamera. The system is ideal for teaching, training, simulation, patient briefings and research. In this thesis the virtual reality system, its development and operation is described in detail.
Open Access
Embedding tamper-resistant, publicly verifiable random number seeds in permissionless blockchain systems
(IEEE, 2022) Bezuidenhout, Riaan; Nel, Wynand; Maritz, Jacques M.
Many blockchain processes require pseudo-random numbers. This is especially true of blockchain consensus mechanisms that aim to fairly distribute the opportunity to propose new blocks between the participants in the system. The starting point for these processes is a source of randomness that participants cannot manipulate. This paper proposes two methods for embedding random number seeds in a blockchain data structure to serve as inputs to pseudo-random number generators. Because the output of a pseudo-random number generator depends deterministically on its seed, the properties of the seed are critical to the quality of the eventual pseudo-random number produced. Our protocol, B-Rand, embeds random number seeds that are confidential , tamper-resistant , unpredictable , collision-resistant , and publicly verifiable as part of every transaction. These seeds may then be used by transaction owners to participate in processes in the blockchain system that require pseudo-random numbers. Both the Single Secret and Double Secret B-Rand protocols are highly scalable with low space and computational cost, and the worst case is linear in the number of transactions per block.
Open Access
Enhancing the user experience for a word processor application through vision and voice
(University of the Free State, 2011) Beelders, Tanya René; Blignaut, P. J.
English: Multimodal interfaces may herald a significant improvement on current GUIs which have been commonplace until now. It is also possible that a multimodal interface could provide a more intuitive and natural means of interaction which, simultaneously, negates the reliance on traditional, manual means of interaction. Eye gaze and speech are common components of natural human-human communication and were proposed for use in a multimodal interface for a popular word processor for the purposes of this study. In order for a combination of eye gaze and speech to be a viable interface for a word processor, it must provide a means of text entry and facilitate editing and formatting of the document contents. For the purposes of this study a simple speech grammar was used to activate common word processing tasks, as well as for selection of text and navigation through a document. For text entry, an onscreen keyboard was provided, the keys of which could be pressed by looking at the desired key and then uttering an acceptable verbal command. These functionalities were provided in an adapted Microsoft Word 2007® to increase the customisability and possibly the usability of the word processor interface and to provide alternative means of interaction. The proposed interaction techniques also had to be able to execute typical mouse actions, such as point-and-click. The usability of eye gaze and speech was determined using longitudinal user testing and a set of tasks specific to the functionality. Results indicated that the use of a gravitational well increased the usability of the speech and eye gaze combination when used for pointing-and-clicking. The use of a magnification tool did not increase the usability of the interaction technique. The gravitational well did, however, result in more incorrect clicks due to natural human behaviour and the ease of target acquisition afforded by the gravitational well. However, participants learnt how to use the interaction technique over the course of time, although the mouse remained the superior pointing device. Speech commands were found to be as usable, or even more usable, than the keyboard and mouse for editing and selection purposes, although navigation was hindered to some extent. For text entry purposes, the keyboard far surpasses eye gaze and speech in terms of performance as an input method as it is both faster and results in fewer errors than eye gaze and speech. However, even though the participants were required to complete a number of sessions and a number of text entry tasks per session, more practice may be required for using eye gaze and speech for text entry. Subjectively, participants felt comfortable with the multimodal interface and also indicated that they felt improvement as they progressed through their sessions. Observations of the participants also indicated that as time passed, the participants became more adept at using the multimodal interface for all necessary interactions. In conclusion, eye gaze and speech can be used instead of a pointing device and speech commands are recommended for use within a word processor in order to accomplish common tasks. For the purposes of text entry, more practice is advocated before a recommendation can be made. Together with progress in hardware development and availability, this multimodal interface may allow the word processor to further exploit emerging technologies and be a forerunner in the use of multimodal interfaces in other applications.
Open Access
Evaluating and improving the usability of e-government websites in Sub-Saharan Africa for enhancing citizen adoption and usage
(University of the Free State, 2017) Verkijika, Silas Formunyuy; De Wet, Lizette
𝑬𝒏𝒈𝒍𝒊𝒔𝒉 E-government has been widely known to be an important factor for fostering a nation’s economic and social development. It holds enormous potential for improving the administrative efficiency of public institutions, encouraging democratic governance, deracinating public sector corruption, and building trust between citizens/private sector and governments. However, most e-government initiatives to date have failed to attain their full potential, because they are increasingly plagued by usability issues. The case is worse for e-government initiatives in Sub-Saharan Africa (SSA) as many researchers have posited that this region is the least developed with regards to e-government diffusion. Moreover, its e-government systems are mostly characterised by poor usability. Consequently, advancing e-government in SSA necessitates advancing the usability of current e-government systems in the region, as usability has been shown to be a vital precondition for e-government progress. As such, this study had as primary objective to develop a model for improving the usability of e-government websites in SSA. The study focused on e-government websites as these sites are generally acknowledged to be the primary platform for government interaction with citizens and other stakeholders. In order to achieve this goal, the design science research (DSR) approach was used as the overall research method for this thesis. The DSR was selected due to its core focus on developing useful artefacts that can effectively address DSR problems. This research approach was further supported by mixed methods encompassing usability evaluation (heuristic evaluation and automated testing) and cross-sectional analysis of national indicators. Using a six-dimensional framework as the core theoretical framework for assessing the usability of e-government websites in SSA, the study concluded that SSA e-government websites were currently characterised by poor usability. After evaluating 279 e-government websites from 31 SSA countries, it was observed that the average usability score for the websites was 36.2%, with the most usable website having a score of 64.8%, while the least usable website scored 10.8%. The poor level of usability was consistent for all the six dimensions. Out of a weighted score of 16.7 for each dimension, the following mean scores were obtained: 7.6 for online services, 6.3 for user-help and feedback, 6.2 for navigation, 5.7 for legitimacy, 5.4 for information architecture, and 3.3 for accessibility accommodation. The study further identified 8 national indicators (corruption, cybersecurity, gender inequality, global competitiveness, human development, innovation, national income, and population age distribution) with significant associations to both e-government development and the usability of e-government websites in SSA. Based on these findings, a policy-ingrained model was proposed for advancing the usability of e-government websites in SSA. The model comprised of four mental models (government, designer, evaluator, and user), with each having both general and specific strategies for improving e-government website usability in SSA. Additionally, the model presented the practical and policy implications regarding the role that the identified national indicators could play in advancing e-government website usability in the region. Moreover, the model was accompanied by a quick assessment checklist that could be used by IT staff of government agencies to evaluate their websites in order to determine which strategies from the model could be applied. The outcomes of this study could contribute to the development of practical and policy-based solutions for improving the usability of e-government websites in SSA, as well as advance the theoretical knowledge base on the use of information systems in government. ___________________________________________________________________
Open Access
The feasibility of an effective data warehousing solution for a tertiary institution
(University of the Free State, 2008) Nazir, Amer Bin; McDonald, Theo
English: Even though industry in South Africa has utilized data warehousing technologies successfully for a number of years, tertiary institutions have lagged behind. This can in part be attributed to the high costs involved, many failures in the past and the fact that the decision makers of these institutions are unaware of what data warehousing is and the advantages it can bring. Several factors, however, are forcing tertiary institutions in the direction of data warehousing. They need all the help they can get to make this process as easy as possible. Most of the tertiary institutions that still survive today came through periods of tough rationalizations and mergers. In order to stay alive and competitive, they have grown through the years and have developed into large businesses in and of themselves. On the one hand they had to make ends meet with subsidies from government that became less and less and on the other hand they had to provide more and more detailed statistics to the government. This change has resulted in a more business-like management of these institutions. Strategic decision making has now become of the utmost importance to tertiary institutions to meet the frequent changes in the government funding structure. The University of the Free State initially tried to accomplish that with an online transaction processing system developed in-house. These systems, however, are designed to optimize transactional processing and the features which increase the efficiency of these systems are generally those which also make it difficult to extract information. When that did not work, a new online transaction processing system was bought from an international company at a huge cost. During the course of data transfer from the old to the new system (with a different database design) numerous data conversion errors generated anomalies and a lack of integrity in the database. The new system also proved inadequate to provide the necessary statistics required by the Department of Education. A system was subsequently purchased that utilized ASCII files prepared by the online transaction processing system which generated fixed reports according to the Department of Education requirements. This system provided a workable solution, but with changes in requirements, new reports need to be developed continuously. It was also worthless for institutional planning and forecasting. This study reported the advantages and disadvantages of the current systems in use to provide statistics to the Department of Education. It then proposes a new system based on data warehousing principles. The dimensional star schema design for a data warehouse is provided. The methods used to transfer, load and extract data are discussed in detail. The data warehouse solution is then compared to the current solutions. The conclusion is that a data warehouse is a feasible solution for the strategic information problems tertiary institutions are facing today. An effective management information system using data warehousing can be developed in-house with low budgets, institutional data can be fitted into dimensional modelling star schemas, and error free data can be provided to end-users by developing proper extraction, transformation and loading packages. The data surfaced to end-users from relational online analytical processing can provide statistics to government and can be used for general planning and forecasting purposes.