A semi-automatic computer-aided assessment framework for primary mathematics

Assessment and feedback processes shape students behaviour, learning and skill development. Computer-aided assessments are increasingly being used to support problem-solving, marking and feedback activities. However, many computer-aided assessment environments only replicate traditional pencil-and-paper tasks. Attention is on grading and providing feedback on the final product of assessment tasks rather than the processes of problem solving. Focusing on steps and problem-solving processes can help teachers to diagnose strengths and weaknesses, discover problem-solving strategies, and to provide appropriate feedback to students. This thesis presents a semi-automatic framework for capturing and marking students solution steps in the context of elementary school mathematics. The first focus is on providing an interactive touch-based tool called MuTAT to facilitate interactive problem solving for students. The second focus is on providing a marking tool named Marking Assistant which utilises the case-based reasoning artificial intelligence methodology to carry out marking and feedback activities more efficiently and consistently. Results from studies carried out with students showed that the MuTAT prototype tool was usable, and performance scores on it were comparable to those obtained when paper-and-pencil was used. More importantly, the MuTAT provided more explicit information on the problem-solving process, showing the students thinking. The captured data allowed for the detection of arithmetic strategies used by the students. Exploratory studies conducted using the Marking Assistant prototype showed that 26% savings in marking time can be achieved compared to traditional paper-and-pencil marking and feedback. The broad feedback capabilities the research tools provided can enable teachers to evaluate whether intended learning outcomes are being achieved and so decide on required pedagogical interventions. The implications of these results are that innovative CAA environments can enable more direct and engaging assessments which can reduce staff workloads while improving the quality of assessment and feedback for students

Experimental analysis of intrusion detection systems using machine learning algorithms and artificial neural networks

Since the invention of the internet for military and academic research purposes, it has evolved to meet the demands of the increasing number of users on the network, who have their scope beyond military and academics. As the scope of the network expanded maintaining its security became a matter of increasing importance. With various users and interconnections of more diversified networks, the internet needs to be maintained as securely as possible for the transmission of sensitive information to be one hundred per cent safe; several anomalies may intrude on private networks. Several research works have been released around network security and this research seeks to add to the already existing body of knowledge by expounding on these attacks, proffering efficient measures to detect network intrusions, and introducing an ensemble classifier: a combination of 3 different machine learning algorithms. An ensemble classifier is used for detecting remote to local (R2L) attacks, which showed the lowest level of accuracy when the network dataset is tested using single machine learning models but the ensemble classifier gives an overall efficiency of 99.8%

Two case reports on Mandibular metastases

Metastatic tumours of the oral cavity are not common. The most common site for bone metastases in the head and neck region is the mandible. Metastatic lesion of the mandible most commonly originate from the lungs in men and breast in women, and these lesions (or tumours) usually are carcinomas rather than sarcomas. We report two cases of metastatic lesions in the mandible: (1) A 19year old male with right mandibular swelling and a nodular swelling in the distal two–third of the right tibia. Radiograghs revealed sclerotic lesion with a sunburst appearance in both the jaw and tibia. Histology of the jaw lesion confirmed a metastatic osteosarcoma of the mandible. (2) A 51year old female with a right mandibular swelling with associated swelling in the anterior neck, right shoulder and right parietal region of the skull. Computerised tomography scan (CT) of the jaws showed an osteolytic lesion of the right mandible. CT scan of the brain also showed a large lytic lesion seen in the posterior aspect of the right parietal bone. Histology of the jaw mass confirmed a metastatic follicular carcinoma from the thyroid. Mandibular metastasis may be the first presenting feature of underlying occult malignancy of another primary site. Therefore, clinicians should maintain a high level of suspicion while evaluating patients with a history of cancer presenting with oral lesions. Keywords: metastatic tumours, mandible, tibia, thyroi

A semi-automatic computer-aided assessment approach for marking and providing feedback comments

Assessment is an essential part of the learning process. It is important for educators to provide detailed and reliable evaluations to students so that they can be better prepared for future studies and the workplace. Marking and providing formative feedback can be time-consuming and prone to errors especially when detailed analyses of students’ problem-solving steps are considered. A computer-aided marking and feedback support tool that aims at improving the efficiency and effectiveness of human marking may result in reduced marking time, improved consistency in marking, and improved feedback capabilities. This paper discusses a semi-automatic approach to marking problem-solving steps in the context of elementary school mathematics using analytical assessment rubrics. A prototype tool which implements the approach is described following recommendations based on research evidence in mathematics problem solving. The tool was evaluated in an observational study which compared marking-time efficiencies obtained using the technique with those obtained from marking done manually. The result suggests that the method has the potentials to facilitate broad feedback delivery, improve marking consistency and may save on marking time. The use of such marking and feedback support systems may contribute to the overall educational goal of more accurate and consistent assessment procedures

Touch arithmetic: a process-based computer-aided assessment approach for capture of problem solving steps in the context of elementary mathematics

Technology today offers many new opportunities for innovation in educational assessment and feedback through rich assessment tasks, efficient scoring and reporting. However many Computer-Aided Assessment (CAA) environments focus on grading and providing feedback on the final product of assessment tasks rather than the process of problem solving. Focusing on steps and problem-solving processes can help teachers to diagnose strengths and weaknesses, discover strategies, and to provide appropriate feedback. This study explores a method that uses trace links on an interactive touch-based computing tool for the capture and analysis of solution steps in elementary mathematics. The tool was evaluated in an observational study among 8 and 9 year old primary school children (N=39). The approach yielded similar performance scores as compared to paper-and-pencil tests while providing more explicit information on the problem-solving process. The output data was useful for scoring intermediate and final answers as well as feedback information on types and time efficiencies of strategies used. An implication of this study for teachers and researchers is that they can more accurately assess students’ understanding of important concepts, and be in a better position to provide rich and detailed feedback while motivating students with interactive tasks

Use of multi-touch gestures for capturing solution steps in arithmetic word problems

Multi-touch interfaces are becoming popular with tablet PCs and other multi-touch surfaces increasingly used in classrooms. Several studies have focused on the development of learning and collaboration potentials of these tools. However, assessment and feedback processes are yet to leverage on the new technologies to capture problem solving steps and strategies. This paper describes a computer aided assessment prototype tool that uses an innovative approach of multi-touch gestures to capture solution steps and strategies. It presents a preliminary effort to investigate the capturing of solution steps involving a two- step arithmetic word problem using the approach. The results suggest that it is possible to perform two step arithmetic work with multi-touch gestures and simultaneously capture solution processes. The steps captured provided detailed information on the students’ work which was used to study possible strategies adopted in solving the problems. This research suggests some practical implications for development of automated feedback and assessment systems and could serve as a base for future studies on effective strategies in arithmetic problem solving

Physico-chemical properties of municipal refuse in Lagos metropolis and cellulolytic activities of resident microorganisms associated with organic matter degradation

This study investigated the activities of micro organisms involved in the degradation of organic matter in solid wastes and their potential to produce cellulolytic enzymes. Soil samples of decomposing waste piles were collected from four designated landfill sites in Lagos metropolis and analyzed for physicochemical properties, toxic heavy metal content and microbial populations. Findings revealed that the moisture content of the soils ranged from 7.6 - 10.0% in all the locations sampled. Ojota-Olusosun site had the highest organic matter content of 10.65%. The highest viable bacterial counts were 28.2 ± 3.0 x 106 cfu/g while fungi were 47.0 ± 4.0 x 104 cfu/g respectively. A similar pattern was observed for phosphate and chloride levels while some heavy metals were also detected in varying and high amounts. There was a significant positive correlation at 5% level between fungal viable counts and phosphate ion while a significant negative correlation was observed for total hydrocarbon. The bacteria associated with the soil samples were identified as Escherichia coli, Bacillus spp, Klebisella spp, Micrococcus spp. and Acinetobacter spp while the resident fungal species were mostly the Aspergillus spp and an isolate identified as Mucor spp. The moulds were found to be capable of utilising lignin and cellulosic substrates for growth and for production of cellulolytic enzymes. Results from this study suggest that such micro organisms could be useful in bioconversion of cellulosic substrates and solid wastes to cellulolytic enzymes for industrial processes

PERFORMANCE EVALUATION OF MULTIPLE TRANSFORM WATERMARKING SYSTEM FOR PRIVACY PROTECTION OF MEDICAL DATA USING PSNR AND NC

This paper presents the performance evaluation of a developed multiple transform watermarking system for privacy protection of medical data using Peak Signal to Noise Ratio (PSNR) and Normalized Cross-Correlation (NC). The PSNR was used to evaluate the imperceptibility of the system, while the NC was used to evaluate the robustness of the system under the various attacks include: Gaussian noise, pepper and salt noise, sharp enhancing, image cutting, image compression, low pass filter and image rotation. The obtained result showed that the similarity between original image and watermarked image has PSNR of 52.4595dB as compared to the existing system of 50.0285dB. This indicates that the proposed scheme can conceal the watermark better, and as well retains the image quality

Cervicofacial Necrotizing Fasciitis in Patients with No Underlying Medical Conditions: A Review of Four Cases Seen in Twelve Months at a Nigerian Tertiary Hospital

Necrotizing fasciitis of the head and neck is a rare but rapidly progressive infection involving the skin, subcutaneous tissue, and fascia. We report 4 cases of cervicofacial necrotizing fasciitis with similar patterns of presentation. All the 4 cases presented with an odontogenic source and no underlying medical condition. All the patients had tooth extraction and serial wound debridement. Three of these patients recovered well, and healing of the wound occurred by secondary intention. One patient had a resultant neck defect, which was repaired with a supraclavicular island flap after the infection had subsided. We advocate the importance of early detection of necrotizing fasciitis with or without an underlying medical condition and an aggressive medical and surgical intervention. Additionally, eradication of the source of infection is highly indicated to reduce the mortality of this disease

2k Factorial Experiments on Factors that Influence the Recovery of Gold during the Upgrade of Ilesha-Itagunmodi Gold Ore through Froth Flotation

A low-grade gold ore from Ilesha-Itagunmodi, south western Nigeria was panned, dried and ball-milled before sieving into fractions. The morphological, mineralogical and chemical composition was studied by optical micro-scopy (Reflected and Transmission), X-ray diffraction (XRD) and Energy Dispersive X-ray fluorescence (XRF), respectively. The sieved fractions were subjected to chemical analysis (AAS). The +106 μm sieve had the highest concentration of the mineral and was then selected for the upgrade through froth flotation using standard rea-gents. In this paper a report on a 2k factorial experiment that provides an understanding of the impact of opera-tional variables on the quantity of gold mineral obtained from the ore during froth flotation is presented. Analy-sis results showed that Ilesha-Itagunmodi gold ore is non-refractory with fine grain particles, amenable to froth flotation and contained about 20 other associated minerals, gold had a concentration of about 0.0024%. A com-bination of P-Xanthate and amine glycol collectors at a pH of 9.2 only produced a considerable increase in gold yield. This translated to about 87.13% increase in recovery of gold from the ore. Analysis of variance (ANOVA) was carried out and the model equation obtained was subsequently optimised to obtain a model equation that could be used in predicting the recoverable quantity of gold, indicating that F11,1-values for Collector concentra-tion, Frother concentration, pH and Conditioning time were 156.86, 6.96, 43.81, and 56.77 respectively. A model with an F value of 88.41 was obtained which indicated that the model was significant. The model equation obtained was subsequently optimised to be able to predict the recoverable quantity of gold. A “Pred R-Squared” value of 0.9365 (93.65%) was also obtained and is in reasonable agreement with the “Adj R-Squared” value of 0.9534 (95.34%). It was established that Ilesha placer gold ore is amenable to froth flotation using standard reagents