Ian Sanders - Academia.edu (original) (raw)
Papers by Ian Sanders
IST-Africa Week Conference, May 9, 2018
Recognition of hand-drawn images is an easy task for human beings, but a challenging and cumberso... more Recognition of hand-drawn images is an easy task for human beings, but a challenging and cumbersome task for the computer to do automatically due to many factors including handwriting variations. This paper focuses on image pre-processing and feature extraction and proposes an effective offline technique to process handdrawn finite automata (FAs). Pre-processing techniques are the first approach in a recognition system. We applied a number of pre-processing techniques to 20 handdrawn FA images to see how feasible it is to extract the primitives of the input FA images. The output of the pre-processing stage was used as an input for the feature extraction stage. The histogram of oriented gradients (HOG) technique was used to extract the features in an FA diagram. A HOG descriptor takes the visual components of an input FA and describes them by the edge directions. The result of our experiment shows that using a HOG algorithm reduces the dimensionality of the feature space without disturbing the performance of the classifier, thus maintaining high efficiency with little computational complexity. Also, our experiment result shows that our system produced good results that can be used in classification.
ABSTRACT In this paper cycle picking in defined as an optimisation problem where cycles are chose... more ABSTRACT In this paper cycle picking in defined as an optimisation problem where cycles are chosen from a directed graph under the constraint that any node that is in a cycle in the original directed graph must be in at least one of the chosen cycles. This problem is an abstraction of a real-world problem where people who require different sized shoes cooperate to be able to buy shoes that fit. The paper considers a number of variations of the problem -- the minimum number of cycles, the all small cycles and the minimum total cycle length views. The paper also shows how the directed graph can be amended to ensure that every node in the original graph is in at least one cycle of an augmented graph before the optimisation phase commences. This is the equivalent of adding dummy people to the group of all people who need shoes to ensure that everyone who needs shoes has a group (even if it contains dummy nodes) of other people with whom to cooperate. Finally a simple greedy heuristic approach for finding approximate solutions to instances of the problem is considered.
Canadian Conference on Computational Geometry, 1998
ABSTRACT In an earlier paper the notion of a ray guard, a guard that can only see along a single ... more ABSTRACT In an earlier paper the notion of a ray guard, a guard that can only see along a single ray, was introduced. Ray guarding means siting the fewest possible guards that guard all adjacencies (shared edges or parts of edges) in an orthogonal arrangement of adjacent nonoverlapping rectangles. In the earlier paper the problem was restricted by requiring that the direction of sight be parallel to one of the Cartesian axes. This problem was shown to be NP-Complete by a transformation from the vertex cover problem for planar graphs. This paper discusses the more general problem where the rays are not restricted to being orthogonal, the same ray can thus cut both horizontal and vertical adjacencies between adjacent rectangles. The problem is shown to be NP-Complete by a transformation from planar vertex cover. The problem of siting ray guards to cover the adjacencies between adjacent convex polygons is a more general case of the non-orthogonal ray guarding problem and the NP-Completeness proof c...
This research addresses the problem of partial edge visibility. This problem stems from work done... more This research addresses the problem of partial edge visibility. This problem stems from work done in the ray guarding of configurations of adjacent rectangles [7]. In ray guarding these configurations it is necessary to be able to find a straight line through a set of adjacencies in a group of adjacent rectangles. If the adjacent rectangles are visualised as an orthogonal polygon whose boundary is the boundaries of the rectangles excluding the adjacencies between the rectangles then the problem is one of finding a straight line from one edge in the polygon to another that is completely contained in the polygon. Partial edge visibility is thus the ability to determine whether one edge of a polygon can "see" another edge in the same polygon. This research derived an algorithm to answer the question "Is some part of edge ef of a given simple polygon visible to some part of edge el of the polygon?" The problem domain places some constraints on the simple polygons that can occur and these constraints were used in developing the algorithm. The final algorithm obtained is linear in the number of polygon vertices. Future work in this area will focus on adapting the algorithm to solve the problem of ray guarding general convex polygons
Recursion is a fundamental concept in Computer Science. A student&amp... more Recursion is a fundamental concept in Computer Science. A student's knowledge of recursion can be termed their models were also constructed. Identifying the models that students have can allow lecturers to target individual students' specific problems and analysis of the models can provide insight into learning.
Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie, 2016
South African Journal of Science and Technology, Feb 11, 2016
South African Computer Journal, Dec 1, 2004
Axial line placement is a computational geometry problem with direct applications to Space Syntax... more Axial line placement is a computational geometry problem with direct applications to Space Syntax Analysis, a technique used in the analysis of building and city layouts. While it has been shown that the general axial line placement problem is NP-complete, polynomial time solutions have been found for several restricted versions of the problem. Of these, the case of urban grids is the most applicable to space syntax. Urban grids are polygons that can be used to represent some real-world layouts, but are relatively restricted in their modelling power. The concept of a deformed urban grid was therefore introduced in an attempt to find a more flexible structure, while retaining the grid-like nature of urban grids. It was originally conjectured that this restricted nature of deformed urban grids would allow for an exact polynomial time solution of the problem. However, this article presents a proof showing that the axial line placement problem for deformed urban grids is NP-complete. As this result holds for grids with relatively little deformation, it seems likely that urban grids are the most general input instance for which exact polynomial time solutions can be found. The development of good heuristic solutions to more general instances of the problem will therefore be crucial in the automation of space syntax.
Communications in Computer and Information Science, 2021
2021 IST-Africa Conference (IST-Africa), 2021
Some educators make use of manipulatives for teaching Computer Science 1 (CS1) concepts in introd... more Some educators make use of manipulatives for teaching Computer Science 1 (CS1) concepts in introductory programming courses. Their aim is to foster or enhance CS1 students’ comprehension, especially of the concepts that may be difficult or too abstract to comprehend. No framework validating the efficacy of using manipulatives to teach CS1 concepts could be found in the literature. The overall study is embarking on extensive research to identify and test manipulatives suitable for teaching challenging CS1 concepts with the aim of developing such a framework. However, in this paper we discuss manipulatives we used to teach and foster understanding of the assignment statement. The early results indicate the effectiveness of teaching and learning with manipulatives. This is ongoing research and more experiments to test other manipulatives will follow through our practical action research methodology.
Guarding and covering problems have great importance in Computational Geometry. In this paper the... more Guarding and covering problems have great importance in Computational Geometry. In this paper the notion of a ray guard, a guard that can only 'see' along a single ray, is introduced. The problem of siting the fewest possible such guards so that they guard all adjacencies in an orthogonal arrangement of adjacent non-overlapping rectangles is discussed. The problem is further restricted by requiring that the direction of sight be parallel to an axis and that the guards cannot 'see' outside the rectangles. The problem is motivated by applications in architecture and urban planning. This paper shows that the problem is NP-Complete because of the locally indeterminate choice which can be introduced in positioning guards. A heuristic algorithm to produce a non-redundant set of guards is then presented. Given n rectangles, the algorithm runs in O(n2) time and O(n2) space and proves to be a good approximation in a number of test cases
In visual password systems it is important to display distractor pictures along with the user’s p... more In visual password systems it is important to display distractor pictures along with the user’s password picture on the authentication screen. These distractors should be similar to the password picture to make it difficult for shoulder surfers to easily identify the true password picture. In this work, we present approaches to generating similar pictures using bag context picture grammars (BCPGs). We describe how these approaches are implemented and present galleries of pictures that have similar characteristics. We then determine the mathematical similarity of the generated pictures, using the spatial colour distribution descriptor (SpCD). The spatial colour distribution descriptor has been shown to be effective in determining the similarity of computer-generated pictures in previous research, and so was seen as a good similarity measure for this research. We then describe an online survey that was conducted to determine the perceptual similarity of the pictures generated by the p...
Multimedia Tools and Applications, 2020
E-learning enables the dissemination of valuable academic information to all users regardless of ... more E-learning enables the dissemination of valuable academic information to all users regardless of where they are situated. One of the challenges faced by e-learning systems is the lack of constant interaction between the user and the system. This observability feature is an essential feature of a typical classroom setting and a means of detecting or observing feature reactions and thus such features in the form of expressions should be incorporated into an e-learning platform. The proposed solution is the implementation of a deep-learning-based facial image analysis model to estimate the learning affect and to reflect on the level of student engagement. This work proposes the use of a Temporal Relational Network (T RN), for identifying the changes in the emotions on students' faces during e-learning session. It is observed that T RN sparsely samples individual frames and then learns their causal relations, which is much more efficient than sampling dense frames and convolving them. In this paper, single-scale and multi-scale temporal relations are considered to achieve the proposed goal. Furthermore, a Multi-Layer Perceptron (MLP) is also tested as a baseline classifier. The proposed framework is end-to-end trainable for video-based Facial Emotion Recognition (FER). The proposed FER model was tested on the open-source DISFA+ database. The T RN based model showed a significant reduction in the length of the feature set which were effective in recognizing expressions. It is observed that the multi-scale T RN has produced better accuracy than the single-scale T RN and MLP with an accuracy of 92.7%, 89.4%, and 86.6% respectively.
Journal of Computer Languages, 2019
Abstract Random context picture grammars (RCPGs) have become established as a method of syntactic... more Abstract Random context picture grammars (RCPGs) have become established as a method of syntactic picture generation. They are context-free grammars with regulated rewriting, where the application of a rule in the grammar is regulated by two sets of variables, the so-called permitting and forbidding context sets. In this paper, we introduce bag context picture grammars (BCPGs). They are also context-free grammars, but the application of a rule is regulated by a k-tuple of integers, the so-called bag, which changes during a derivation. We prove that any RCPG can be written as a BCPG and illustrate the rewriting process with several examples. We then consider one set of pictures and discuss why it is easier to write a BCPG that generates a variation on the set, and modify that BCPG again, should we wish to, than to do the same to the RCPG that generates the original picture set. This allows for application in visual password systems.
International Journal of Human–Computer Interaction
The 2020 health pandemic brought renewed interest in using learning management systems (LMSs) to ... more The 2020 health pandemic brought renewed interest in using learning management systems (LMSs) to deliver educational services as routinely done in open distance and electronic learning (ODeL) environments. LMSs usability has been researched but the lecturers' perspective remains unexplored. The purpose of this study was to propose validated usability guidelines for an LMS in an ODeL context. A set of usability requirements was abstracted from the literature and used as the basis for a heuristic evaluation (HE) of the institution's LMS. These results of the HE was triangulated with three other usability evaluation methods including usability testing with eye tracking, a post-test system usability scale (SUS) questionnaire and interviews. The primary contribution is the validated usability requirements for ODeL LMSs based on the lecturers' perspective. A secondary contribution is the triangulation approach to evaluating the guidelines in situ which confirmed HE as a valid evaluation method for LMSs.
Wireless Communications and Mobile Computing
Various studies have measured and analyzed learners’ emotions in both traditional classroom and e... more Various studies have measured and analyzed learners’ emotions in both traditional classroom and e-learning settings. Learners’ emotions can be estimated using their text input, speech, body language, or facial expressions. The presence of certain facial expressions has shown to indicate a learner’s levels of concentration in both traditional and e-learning environments. Many studies have focused on the use of facial expressions in estimating the emotions experienced by learners. However, little research has been conducted on the use of analyzed emotions in estimating the learning affect experienced. Previous studies have shown that online learning can enhance students’ motivation, interest, attention, and performance as well as counteract negative emotions, such as boredom and anxiety, that students may experience. Thus, it is crucial to integrate modules into an existing e-learning platform to effectively estimate learners’ learning affect (LLA), provide appropriate feedback to bot...
2021 IST-Africa Conference (IST-Africa), 2021
Honours students, who are mostly new to research, require support in finding, selecting and shari... more Honours students, who are mostly new to research, require support in finding, selecting and sharing information resources to conduct research. Providing students with access to information resources becomes problematic in Open and Distance Learning (ODL), especially in developing countries due to constraints that are introduced by distance among the students, and between students and the supervisors. The constraints include isolation, lack of peer collaboration, the cost of Internet facilities, and time management for working students. Mobile applications could offer solutions, but the extant literature offers little guidance on the functional design of such applications. This design science research study presents a mobile tool with an interface for information access, information sharing and collaboration. The evaluation results show that the tool supports collaboration effectively by allowing students to access and share information. Besides the proof of concept, the theoretical ...
Proceedings of the 13th International Conference on Computer Supported Education, 2021
Programming is one of the major subjects within the field of computing. In the higher education s... more Programming is one of the major subjects within the field of computing. In the higher education sector, some introductory programming students succeed while others find it difficult to progress or learn the material. Methods of teaching to program do not accommodate struggling students. Among introductory programming issues, the nested-decision statement is one of the misconceived concepts. In the literature, there is evidence that some programming educators make use of physical manipulatives to teach introductory programming. However, there is no framework or validation methods used to identify and use the manipulatives. In this study, we designed a manipulative called Nested-decider to assist struggling introductory programming students to develop an appropriate conceptual knowledge about nested-decisions. The details of the design and its functionalities are presented in this paper. We believe that teaching and learning nested-decisions with the proposed Nested-decider manipulative could be a useful pedagogical intervention towards enhancing struggling students' comprehension. This is ongoing research where we identify and test various manipulatives for struggling introductory programming students. The results will also help us to develop a manipulatives-oriented pedagogical framework, which can be used to inform identification and use of manipulatives.
South African Computer Journal
This article explores what constitutes an acceptable PhD, with some examples of the failings the ... more This article explores what constitutes an acceptable PhD, with some examples of the failings the author has noticed in theses he has been asked to examine or in his own students’ drafts.
IST-Africa Week Conference, May 9, 2018
Recognition of hand-drawn images is an easy task for human beings, but a challenging and cumberso... more Recognition of hand-drawn images is an easy task for human beings, but a challenging and cumbersome task for the computer to do automatically due to many factors including handwriting variations. This paper focuses on image pre-processing and feature extraction and proposes an effective offline technique to process handdrawn finite automata (FAs). Pre-processing techniques are the first approach in a recognition system. We applied a number of pre-processing techniques to 20 handdrawn FA images to see how feasible it is to extract the primitives of the input FA images. The output of the pre-processing stage was used as an input for the feature extraction stage. The histogram of oriented gradients (HOG) technique was used to extract the features in an FA diagram. A HOG descriptor takes the visual components of an input FA and describes them by the edge directions. The result of our experiment shows that using a HOG algorithm reduces the dimensionality of the feature space without disturbing the performance of the classifier, thus maintaining high efficiency with little computational complexity. Also, our experiment result shows that our system produced good results that can be used in classification.
ABSTRACT In this paper cycle picking in defined as an optimisation problem where cycles are chose... more ABSTRACT In this paper cycle picking in defined as an optimisation problem where cycles are chosen from a directed graph under the constraint that any node that is in a cycle in the original directed graph must be in at least one of the chosen cycles. This problem is an abstraction of a real-world problem where people who require different sized shoes cooperate to be able to buy shoes that fit. The paper considers a number of variations of the problem -- the minimum number of cycles, the all small cycles and the minimum total cycle length views. The paper also shows how the directed graph can be amended to ensure that every node in the original graph is in at least one cycle of an augmented graph before the optimisation phase commences. This is the equivalent of adding dummy people to the group of all people who need shoes to ensure that everyone who needs shoes has a group (even if it contains dummy nodes) of other people with whom to cooperate. Finally a simple greedy heuristic approach for finding approximate solutions to instances of the problem is considered.
Canadian Conference on Computational Geometry, 1998
ABSTRACT In an earlier paper the notion of a ray guard, a guard that can only see along a single ... more ABSTRACT In an earlier paper the notion of a ray guard, a guard that can only see along a single ray, was introduced. Ray guarding means siting the fewest possible guards that guard all adjacencies (shared edges or parts of edges) in an orthogonal arrangement of adjacent nonoverlapping rectangles. In the earlier paper the problem was restricted by requiring that the direction of sight be parallel to one of the Cartesian axes. This problem was shown to be NP-Complete by a transformation from the vertex cover problem for planar graphs. This paper discusses the more general problem where the rays are not restricted to being orthogonal, the same ray can thus cut both horizontal and vertical adjacencies between adjacent rectangles. The problem is shown to be NP-Complete by a transformation from planar vertex cover. The problem of siting ray guards to cover the adjacencies between adjacent convex polygons is a more general case of the non-orthogonal ray guarding problem and the NP-Completeness proof c...
This research addresses the problem of partial edge visibility. This problem stems from work done... more This research addresses the problem of partial edge visibility. This problem stems from work done in the ray guarding of configurations of adjacent rectangles [7]. In ray guarding these configurations it is necessary to be able to find a straight line through a set of adjacencies in a group of adjacent rectangles. If the adjacent rectangles are visualised as an orthogonal polygon whose boundary is the boundaries of the rectangles excluding the adjacencies between the rectangles then the problem is one of finding a straight line from one edge in the polygon to another that is completely contained in the polygon. Partial edge visibility is thus the ability to determine whether one edge of a polygon can "see" another edge in the same polygon. This research derived an algorithm to answer the question "Is some part of edge ef of a given simple polygon visible to some part of edge el of the polygon?" The problem domain places some constraints on the simple polygons that can occur and these constraints were used in developing the algorithm. The final algorithm obtained is linear in the number of polygon vertices. Future work in this area will focus on adapting the algorithm to solve the problem of ray guarding general convex polygons
Recursion is a fundamental concept in Computer Science. A student&amp... more Recursion is a fundamental concept in Computer Science. A student's knowledge of recursion can be termed their models were also constructed. Identifying the models that students have can allow lecturers to target individual students' specific problems and analysis of the models can provide insight into learning.
Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie, 2016
South African Journal of Science and Technology, Feb 11, 2016
South African Computer Journal, Dec 1, 2004
Axial line placement is a computational geometry problem with direct applications to Space Syntax... more Axial line placement is a computational geometry problem with direct applications to Space Syntax Analysis, a technique used in the analysis of building and city layouts. While it has been shown that the general axial line placement problem is NP-complete, polynomial time solutions have been found for several restricted versions of the problem. Of these, the case of urban grids is the most applicable to space syntax. Urban grids are polygons that can be used to represent some real-world layouts, but are relatively restricted in their modelling power. The concept of a deformed urban grid was therefore introduced in an attempt to find a more flexible structure, while retaining the grid-like nature of urban grids. It was originally conjectured that this restricted nature of deformed urban grids would allow for an exact polynomial time solution of the problem. However, this article presents a proof showing that the axial line placement problem for deformed urban grids is NP-complete. As this result holds for grids with relatively little deformation, it seems likely that urban grids are the most general input instance for which exact polynomial time solutions can be found. The development of good heuristic solutions to more general instances of the problem will therefore be crucial in the automation of space syntax.
Communications in Computer and Information Science, 2021
2021 IST-Africa Conference (IST-Africa), 2021
Some educators make use of manipulatives for teaching Computer Science 1 (CS1) concepts in introd... more Some educators make use of manipulatives for teaching Computer Science 1 (CS1) concepts in introductory programming courses. Their aim is to foster or enhance CS1 students’ comprehension, especially of the concepts that may be difficult or too abstract to comprehend. No framework validating the efficacy of using manipulatives to teach CS1 concepts could be found in the literature. The overall study is embarking on extensive research to identify and test manipulatives suitable for teaching challenging CS1 concepts with the aim of developing such a framework. However, in this paper we discuss manipulatives we used to teach and foster understanding of the assignment statement. The early results indicate the effectiveness of teaching and learning with manipulatives. This is ongoing research and more experiments to test other manipulatives will follow through our practical action research methodology.
Guarding and covering problems have great importance in Computational Geometry. In this paper the... more Guarding and covering problems have great importance in Computational Geometry. In this paper the notion of a ray guard, a guard that can only 'see' along a single ray, is introduced. The problem of siting the fewest possible such guards so that they guard all adjacencies in an orthogonal arrangement of adjacent non-overlapping rectangles is discussed. The problem is further restricted by requiring that the direction of sight be parallel to an axis and that the guards cannot 'see' outside the rectangles. The problem is motivated by applications in architecture and urban planning. This paper shows that the problem is NP-Complete because of the locally indeterminate choice which can be introduced in positioning guards. A heuristic algorithm to produce a non-redundant set of guards is then presented. Given n rectangles, the algorithm runs in O(n2) time and O(n2) space and proves to be a good approximation in a number of test cases
In visual password systems it is important to display distractor pictures along with the user’s p... more In visual password systems it is important to display distractor pictures along with the user’s password picture on the authentication screen. These distractors should be similar to the password picture to make it difficult for shoulder surfers to easily identify the true password picture. In this work, we present approaches to generating similar pictures using bag context picture grammars (BCPGs). We describe how these approaches are implemented and present galleries of pictures that have similar characteristics. We then determine the mathematical similarity of the generated pictures, using the spatial colour distribution descriptor (SpCD). The spatial colour distribution descriptor has been shown to be effective in determining the similarity of computer-generated pictures in previous research, and so was seen as a good similarity measure for this research. We then describe an online survey that was conducted to determine the perceptual similarity of the pictures generated by the p...
Multimedia Tools and Applications, 2020
E-learning enables the dissemination of valuable academic information to all users regardless of ... more E-learning enables the dissemination of valuable academic information to all users regardless of where they are situated. One of the challenges faced by e-learning systems is the lack of constant interaction between the user and the system. This observability feature is an essential feature of a typical classroom setting and a means of detecting or observing feature reactions and thus such features in the form of expressions should be incorporated into an e-learning platform. The proposed solution is the implementation of a deep-learning-based facial image analysis model to estimate the learning affect and to reflect on the level of student engagement. This work proposes the use of a Temporal Relational Network (T RN), for identifying the changes in the emotions on students' faces during e-learning session. It is observed that T RN sparsely samples individual frames and then learns their causal relations, which is much more efficient than sampling dense frames and convolving them. In this paper, single-scale and multi-scale temporal relations are considered to achieve the proposed goal. Furthermore, a Multi-Layer Perceptron (MLP) is also tested as a baseline classifier. The proposed framework is end-to-end trainable for video-based Facial Emotion Recognition (FER). The proposed FER model was tested on the open-source DISFA+ database. The T RN based model showed a significant reduction in the length of the feature set which were effective in recognizing expressions. It is observed that the multi-scale T RN has produced better accuracy than the single-scale T RN and MLP with an accuracy of 92.7%, 89.4%, and 86.6% respectively.
Journal of Computer Languages, 2019
Abstract Random context picture grammars (RCPGs) have become established as a method of syntactic... more Abstract Random context picture grammars (RCPGs) have become established as a method of syntactic picture generation. They are context-free grammars with regulated rewriting, where the application of a rule in the grammar is regulated by two sets of variables, the so-called permitting and forbidding context sets. In this paper, we introduce bag context picture grammars (BCPGs). They are also context-free grammars, but the application of a rule is regulated by a k-tuple of integers, the so-called bag, which changes during a derivation. We prove that any RCPG can be written as a BCPG and illustrate the rewriting process with several examples. We then consider one set of pictures and discuss why it is easier to write a BCPG that generates a variation on the set, and modify that BCPG again, should we wish to, than to do the same to the RCPG that generates the original picture set. This allows for application in visual password systems.
International Journal of Human–Computer Interaction
The 2020 health pandemic brought renewed interest in using learning management systems (LMSs) to ... more The 2020 health pandemic brought renewed interest in using learning management systems (LMSs) to deliver educational services as routinely done in open distance and electronic learning (ODeL) environments. LMSs usability has been researched but the lecturers' perspective remains unexplored. The purpose of this study was to propose validated usability guidelines for an LMS in an ODeL context. A set of usability requirements was abstracted from the literature and used as the basis for a heuristic evaluation (HE) of the institution's LMS. These results of the HE was triangulated with three other usability evaluation methods including usability testing with eye tracking, a post-test system usability scale (SUS) questionnaire and interviews. The primary contribution is the validated usability requirements for ODeL LMSs based on the lecturers' perspective. A secondary contribution is the triangulation approach to evaluating the guidelines in situ which confirmed HE as a valid evaluation method for LMSs.
Wireless Communications and Mobile Computing
Various studies have measured and analyzed learners’ emotions in both traditional classroom and e... more Various studies have measured and analyzed learners’ emotions in both traditional classroom and e-learning settings. Learners’ emotions can be estimated using their text input, speech, body language, or facial expressions. The presence of certain facial expressions has shown to indicate a learner’s levels of concentration in both traditional and e-learning environments. Many studies have focused on the use of facial expressions in estimating the emotions experienced by learners. However, little research has been conducted on the use of analyzed emotions in estimating the learning affect experienced. Previous studies have shown that online learning can enhance students’ motivation, interest, attention, and performance as well as counteract negative emotions, such as boredom and anxiety, that students may experience. Thus, it is crucial to integrate modules into an existing e-learning platform to effectively estimate learners’ learning affect (LLA), provide appropriate feedback to bot...
2021 IST-Africa Conference (IST-Africa), 2021
Honours students, who are mostly new to research, require support in finding, selecting and shari... more Honours students, who are mostly new to research, require support in finding, selecting and sharing information resources to conduct research. Providing students with access to information resources becomes problematic in Open and Distance Learning (ODL), especially in developing countries due to constraints that are introduced by distance among the students, and between students and the supervisors. The constraints include isolation, lack of peer collaboration, the cost of Internet facilities, and time management for working students. Mobile applications could offer solutions, but the extant literature offers little guidance on the functional design of such applications. This design science research study presents a mobile tool with an interface for information access, information sharing and collaboration. The evaluation results show that the tool supports collaboration effectively by allowing students to access and share information. Besides the proof of concept, the theoretical ...
Proceedings of the 13th International Conference on Computer Supported Education, 2021
Programming is one of the major subjects within the field of computing. In the higher education s... more Programming is one of the major subjects within the field of computing. In the higher education sector, some introductory programming students succeed while others find it difficult to progress or learn the material. Methods of teaching to program do not accommodate struggling students. Among introductory programming issues, the nested-decision statement is one of the misconceived concepts. In the literature, there is evidence that some programming educators make use of physical manipulatives to teach introductory programming. However, there is no framework or validation methods used to identify and use the manipulatives. In this study, we designed a manipulative called Nested-decider to assist struggling introductory programming students to develop an appropriate conceptual knowledge about nested-decisions. The details of the design and its functionalities are presented in this paper. We believe that teaching and learning nested-decisions with the proposed Nested-decider manipulative could be a useful pedagogical intervention towards enhancing struggling students' comprehension. This is ongoing research where we identify and test various manipulatives for struggling introductory programming students. The results will also help us to develop a manipulatives-oriented pedagogical framework, which can be used to inform identification and use of manipulatives.
South African Computer Journal
This article explores what constitutes an acceptable PhD, with some examples of the failings the ... more This article explores what constitutes an acceptable PhD, with some examples of the failings the author has noticed in theses he has been asked to examine or in his own students’ drafts.