Browsing by Author "Abdullah, NA"

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item: Article-Full-text
An approach to measure the pedagogy in slides with voice-over type instructional videos
(Academic Publishing, 2022) Suriyawansa, K; Kodagoda, N; Ranathunga, L; Abdullah, NA
E-learning provides a more suitable learning environment for educators and learners. Hence, the e-learning community has rapidly increased over the years. At present, e-learning environments use several materials to transfer knowledge to learners. Out of various types of materials, instructional videos have become the prominent source of information in popular e-learning environments. Instructional videos in e-learning can be categorised into many types based on the content presentation method. Voice-over slides are popular instructional videos at present. Since the instructional materials are a key component of an e-learning environment, maintaining the required quality of these materials is vital. Using proper pedagogy in instructional materials mainly enhances the quality. There are many pedagogical principles proposed over the years, and these principles address different features of all instructional materials. Therefore, it is necessary to derive the applicable pedagogical principles based on the features available in the instructional video to analyse the pedagogy in an instructional video. The investigation related to this paper aims to derive an approach to analysing and quantifying the pedagogy in slides with voice-over type instructional videos. In this study, a thorough literature review first identified the pedagogical principles applicable to slides with voice-over type instructional videos. Next, the prominence of the identified pedagogical principles was derived from a Likert-scale survey conducted by several Information Technology undergraduates. The survey response assigned a rank to each identified pedagogical principle. The rank was derived by the mean score obtained for each pedagogical principle. Next, one-way ANOVA tests were performed for the mean score of pedagogical principles to derive their prominence levels. The ANOVA tests were conducted by adding adjacent pedagogical principles with a non-identical rank until the ANOVA results claimed a significant difference in variances. A new level was defined when the ANOVA results showed a significant difference. This study proposed a pedagogical score calculation formula using these levels (derived from the statistical analysis) to derive a qualitative measure of the use of pedagogy in slides with voice-over type instructional videos. The pedagogical evaluators and content developers can use the proposed scoring method to quantify and compare the pedagogy in slides with voice-over instructional videos.
item: Conference-Abstract
Calibration checklist to use in an automated pedagogical evaluation process of web based E-Learning
(2014-06-20) De Sirisuriya, SCMS; Ranathunga, L; Karunanayaka, SP; Abdullah, NA
E-Learning becomes widely spread in the past few years because it enables learner to participate in anytime, anyplace personalized training. Designing rich E-Learning environment is an important factor to enhancing the effectiveness of web based education. Therefore the necessity of evaluating the web based E-Learning content is arising. The evaluation of E-Learning content is beneficial for learner to choose the best learning material, as well as instructional designer to improve the quality of their learning materials. Inconsistency is the biggest challenge faced by pedagogical reviewers in manual pedagogical evaluation process of web based E-Learning since different institutes used different set of checklists in order to pedagogically evaluate their web based E-Learning content. This paper puts forth web based E-Learning pedagogy evaluation formulae formation technique derived through a standardized checklist, which generally used in pedagogical evaluation process of web based E-Learning content. This wouldhelp to develop a theoretical framework to automate the pedagogical evaluation process of web based E-Learning content and subsequently design and develop a supporting tool for assisting pedagogical reviewers in the evaluating process. Also this paper discusses the challenges and design rational of the tool designed to setup the framework for pedagogy review of web-based E-Learning.
item: Conference-Abstract
Calibration Checklist to Use in an Automated Pedagogical Evaluation Process of Web Based ELearning
(2015-09-18) de S Sirisuriya, SCM; Karunanayaka, SP; Ranathunga, L; Abdullah, NA
E-Learning becomes widely spread in the past few years because it enables learner to participate in anytime, anyplace personalized training. Designing rich E-Learning environment is an important factor to enhancing the effectiveness of web based education. Therefore the necessity of evaluating the web based E-Learning content is arising. The evaluation of ELearning content is beneficial for learner to choose the best learning material,as well as instructional designer to improve the quality of their learning materials. Inconsistency is the biggest challenge faced by pedagogical reviewers in manual pedagogical evaluation process of web based E-Learning since different institutes used different set of checklists in order to pedagogically evaluate their web based E-Learning content. This paper puts forth web based E-Learning pedagogy evaluation formulae formation technique derived through a standardized checklist, which generally used in pedagogical evaluation process of web based E-Learning content.This wouldhelp to develop a theoretical framework to automate the pedagogical evaluation process of web based E-Learning content and subsequently design and develop a supporting tool for assisting pedagogical reviewers in the evaluating process.Also this paper discusses the challenges and design rational of the tool designed to setup the framework for pedagogy review of web-based E-Learning.
item: Conference-Abstract
Can pedagogical evaluation process of web based E-Learning be automated?
(2014-06-24) de S Sirisuriya, SCM; Ranathunga, L; Karunanayaka, SP; Abdullah, NA
E-Learning aims to improve the quality of learning through the use of modern information and communication technologies. Designing E-Learning course materials is the most critical task because its entire educational system depends on the way content is presented. For that reason the necessity of evaluating the web based E-Learning content is arising. The evaluation of E-Learning content is beneficial for learner as well as instructional designer because it facilitates learner to choose the best learning material, and helps designers to improve the quality of their learning materials. This paper describes the importance of automating the pedagogical evaluating process of web based E-Learning contents and the theoretical framework used in the evaluation process. The aim of this research is to improve the quality of the content in e-Learning websites using the feedback given by the automated pedagogical evaluation process.
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Conventional video shot segmentation to semantic shot segmentation
(2015-09-18) Ranathunga, L; Zainuddin, R; Abdullah, NA
Video shot segmentation is a preliminary process used in video content analysis which requires for content description. Conventional shot segmentation techniques nourished with statistical approaches depend on chromatic distributions of video frames. However, these conventional approaches lagging behind in performing semantic shot segmentation where more intuitive and perceptive for human understanding and search. This paper presents a novel mechanism which capable of perform semantic shot segmentation without additional computational and description cost for semantic video content depiction process. This mechanism bypasses the traditional video shot segmentation which is normally performs at the beginning of video content depiction and instead it perform meaningful shot boundary identification at the end based on the results of video visual concept classification. This is a positive starting point to perform structuring of video content using semantic units of shots rather than abrupt discontinued shots. Further, this paper introduces a search mechanism empowered by semantic shot segmentation.
item: Conference-Abstract
A Feature clustering approach based on histogram of oriented optical flow and superpixels
Bandara, AMRR; Ranathunga, L; Abdullah, NA
Visual feature clustering is one of the cost-effective approaches to segment objects in videos. However, the assumptions made for developing the existing algorithms prevent them from being used in situations like segmenting an unknown number of static and moving objects under heavy camera movements. This paper addresses the problem by introducing a clustering approach based on superpixels and short-term Histogram of Oriented Optical Flow (HOOF). Salient Dither Pattern Feature (SDPF) is used as the visual feature to track the flow and Simple Linear Iterative Clustering (SLlC) is used for obtaining the superpixels. This new clustering approach is based on merging superpixels by comparing short term local HOOF and a color cue to form high-level semantic segments. The new approach was compared with one of the latest feature clustering approaches based on K-Means in eight-dimensional space and the results revealed that the new approach is better by means of consistency, completeness, and spatial accuracy. Further, the new approach completely solved the problem of not knowing the number of objects in a scene.
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Hierarchical region based template matching technique for global motion reduction of Coronary Cineangiograms
Kulathilake, KASH; Ranathunga, L; Constantine, GR; Abdullah, NA
The Coronary Cineangiogram (CCA) is an invasive medical image modality which is used to determine the stenosis in the Coronary Arteries. The global motion occurring due to the heart beat makes great disturbance to obtain the visual alignment among the vessel structure shown in the CCA frames. Therefore, the recorded vessel structure’s position in CCA varies within the frame sequence. This paper describes a hierarchical region based template matching technique to reconstruct the CCA by reducing the global motion artifacts. This proposed motion reduction technique is efficient and it reconstructs the CCA by reducing the background motion as desired. Experimental results of this method have shown its’ ability to maintain the visual alignment of the internal blood flow among the frames.
item: Conference-Abstract
Invariant properties of a locally salient dither pattern with a spatial-chromatic histogram
(2014-06-18) Bandara, AMRR; Ranathunga, L; Abdullah, NA
Compacted Dither Pattern Code (CDPC) is a recently found feature which is successful in irregular shapes based visual depiction. Locally salient dither pattern feature is an attempt to expand the capability of CDPC for both regular and irregular shape based visual depiction. This paper presents an analysis of rotational and scale invariance property of locally salient dither pattern feature with a two dimensional spatial-chromatic histogram, which expands the applicability of the visual feature. Experiments were conducted to exhibit rotational and scale invariance of the feature. These experiments were conducted by combining linear Support Vector Machine (SVM) classifier to the new feature. The experimental results revealed that the locally salient dither pattern feature with the spatial-chromatic histogram is rotationally and scale invariant.
item: Article-Abstract
Performance evaluation of the combination of Compacted Dither Pattern Codes with Bhattacharyya classifier in video visual concept depiction
Ranathunga, L; Zainuddin, R; Abdullah, NA
High dimensionality and multi-feature combinations can have negative effect on visual concept classification. In our research, we formulated a new compacted form which is Compacted Dither Pattern Code (CDPC) as a chromatic syntactic feature for visual feature extraction. The effectiveness of CDPC with Bhattacharyya classifier for irregular shapes based visual concepts depiction is reported in this paper. The proposed technique can reduce feature space and computational complexity while maintaining visual data mining and retrieval accuracy in high standard. Our system was empowered with Bhattacharyya classifier which has improved efficiency by considering one numeric value which is the Bhattacharyya coefficient. Experiments were conducted on various combinations and compared with different visual descriptors and classifiers. The first experiment illustrates the comparison of the CDPC based results with well known feature space reduction classes. The second and third experiments demonstrate the effectiveness of our approach with multiple perspectives of performance measures including various concepts.
item: Article-Abstract
Reduction of motion disturbances in Coronary Cineangiograms through template matching
Kulathilake, KASH; Ranathunga, L; Constantine, GR; Abdullah, NA
The coronary cineangiogram (CCA) is an invasive medical image modality which is used to determine the stenosis in Coronary Arteries. The motion artifacts occurring due to the heart pulse makes great disturbance to visualize a stable contrast agent flow within the vessel structure of CCA and it negatively affects to quantify the stenosis based on the functional significance within the arterial flow. This paper describes an application of template matching to reconstruct the CCA by reducing the global motion artifacts. The Normalized Correlation Coefficient (NCC) method has been used for the template matching because, it reports the lowest false matching occurrences. Further, the NCC technique has 99.5% accuracy and demonstrates its ability to maintain the visual correlation of the internal blood flow among the frames. Producing Motion eliminated CCA to maintain the visual correlation of arterial flow is an improvement of angiography technique which can be useful for advanced processing.
item: Conference-Full-text
Region Growing Segmentation Method for Extracting Vessel Structures from Coronary Cine-angiograms
(2015-08-04) Kulathilake, KASH; Ranathunga, L; Constantine, GR; Abdullah, NA
The coronary cine-angiogram (CCA) is an invasive medical image modality which is used to determine the luminal obstructions or stenosis in the Coronary Arteries (CA). CCA based quantitative assessment of vascular morphology is a demanding area in medical diagnosis and segmentation of blood vessels in CCAs is one of the mandatory step in this endeavor. The accurate segmentation of CAs in Angiogram is a challenging task due to various reported reasons. In order to overcome this challenge, we proposed a region growing segmentation method which implements using morphological image processing operations and flood fill method. It can extract the boundary of main CA visualized in the processed CCA completely. The result of the proposed method reveals that this proposed segmentation method possesses 90.89% accuracy to segment the CAs related to the selected Angiography views. This segmentation results can be further enhanced to determine the functional severity of the CA and this study laid the foundation to improve the Angiography based diagnosis technique.
item: Conference-Abstract
Region growing segmentation method for extracting vessel structures from Coronary Cine-angiograms
Kulathilake, KASH; Ranathunga, L; Constantine, GR; Abdullah, NA
The coronary cine-angiogram (CCA) is an invasive medical image modality which is used to determine the luminal obstructions or stenosis in the Coronary Arteries (CA). CCA based quantitative assessment of vascular morphology is a demanding area in medical diagnosis and segmentation of blood vessels in CCAs is one of the mandatory step in this endeavor.The accurate segmentation of CAs in Angiogram is a challenging task due to various reported reasons. In order to overcome this challenge, we proposed a region growing segmentation method which implements using morphological image processing operations and flood fill method. It can extract the boundary of main CA visualized in the processed CCA completely. The result of the proposed method reveals that this proposed segmentation method possesses 90.89% accuracy to segment the CAs related to the selected Angiography views. This segmentation results can be further enhanced to determine the functional severity of the CA and this study laid the foundation to improve the Angiography based diagnosis technique.
item: Conference-Abstract
A Segmentation method for extraction of main arteries from coronary Cine-angiograms
Kulathilake, KASH; Ranathunga, L; Constantine, GR; Abdullah, NA
Coronary Cine- Angiogram (CCA) based subjective assessment of vascular malfunction is a preliminary diagnostic method in Cardiac clinical procedures. Even though there are many other medical image modalities available, improving the CCA method to objectively detect and assess the stenosis is a cost effective approach in Cardiac clinical procedures. Segmentation of Coronary Arteries (CA) is a basic and challenging area in such an endeavour. Hence, in this study we proposed a segmentation method to extract the major areas of CA based on Frangi's vessel enhancement filter and region growing segmentation method called flood fill. Experimental results of our proposed segmentation method have clearly proven its ability to extract the main CA almost completely. Moreover this proposed segmentation method possesses 93.73% average segmentation accuracy. Further, it detects the vessel path lines of the segmented frames using a thinning algorithm. The results obtained from this proposed segmentation method can be further enhanced to determine the functional severity of the CA and this study lays a foundation to improve the Coronary Angiogram image modality to do objective diagnosis of stenosis in future.
item: Conference-Abstract
Spatio Concept relation accompanied interface to bridge semantic gap of video search and retrieval
(2015-09-18) Ranathunga, L; Abdullah, NA; Zainuddin, R
Video search and retrieval becoming hot topic in multimedia information retrieval. However, the ‘semantic gap’ still persists and urges effective mechanisms to bridge the gap. This paper presents an empirical framework, which grabs the user experience to reduce the ‘semantic gap’. The graphical user interface of the system allows visual information seeker to express his idea using semantic concept association by spatially related visual concepts. This study comes with a video content depiction schema that has created the foundation for the semantic search mechanism of Spatial Concept Association Based Search (SCABS). In this approach, the communication between the end user and the video search system has been linked through the depiction schema. This visual retrieval mechanism provides advantages in contrast to common tag based retrieval systems. The experimental results pave the path for the possible improvements inline with semantic video retrieval.
item: Article-Abstract
User’s visual Intention driven retrieval model for semantic video search and retrieval
Ranathunga, L; Abdullah, NA; Zainuddin, R
There are various models of retrieval mechanisms for effective video retrieval, however, ‘semantic gap’ still persists. This study aims to reduce the gap by providing a graphical user interface that allows user to express the visuals in their mind into a query using semantic association of spatial and temporal visual concepts. To accomplish this, we have developed a video content depiction schema that serves as the foundation to our semantic search mechanisms, namely a generic visual concept search, Spatial Concept Association Based Search (SCABS) and Spatial Concept Transition Based Search (SCTBS). In our approach, a clear understanding between the user and the system has been established through the depiction schema and the visual retrieval mechanisms in contrast to common tag based retrieval systems. This retrieval model employs visual experiences and context knowledge of the users to generate search results. Our experiment result shows that our approach produces positive result against other approaches.