57 research outputs found

    Dynamic Street Parking Space Using Memetic Algorithm for Optimization

    Get PDF
    In recent years, there have been an increasing number of automobiles in cities around the world. This is due to more people living and working in cities as a result of urbanization. Street parking remains a common option for motorists, due to it being cheap and convenient. However, this option leads to a high concentration of vehicles causing congestion and obstruction of traffic. This problem is compounded as motorists wait for others to pull out of parking bays or look for empty parking spaces. In order to provide relief to this problem, an intelligent approach is proposed that generates an optimal parking space based on the vehicle location and desired destination. The proposed approach applies its operators adaptively and it derives optimality from the synergy between genetic algorithm and a local search technique in the search optimization process. The proposed method exhibits superior performance when compared with the existing methods over multiple iterations

    E-Learning in Place of Face-to-face Lectures: An Exploratory Study of Students’ Perceptions

    Get PDF
    E-learning has emerged as an essential system in higher education. In an era of technological advancement the move to online learning is inevitable as students are becoming more technically knowledgeable. Based on the Theory of Reasoned Action (TRA) the objectives of this study are to explorestudents’ perceptions towards e-learning as a replacement for face-to-face lectures in the discipline of Information Systems and Technology. A mixed methods approach was utilised. Questionnaires were employed as the primary source of data. A sample of 60 students from the IST disciplineshows that both e-learning and face-to-face lectures were considered relevant for different forms of subject matter. Additionally, it was found thatmost students valued face-to-face lectures in contexts that require a common understanding of cognitively higher level of learning, and students valued elearning for the convenience and ease of use. These findings also suggest that students have different learning styles and therefore researchers should take into consideration instructors’ competence in instructional pedagogy in e-learning. Instructors should, likewise recognize that e-learning may be perceived differently by students. Based on these findings, implications for theory and practice are explained

    Default reasoning and neural networks

    Get PDF
    In this dissertation a formalisation of nonmonotonic reasoning, namely Default logic, is discussed. A proof theory for default logic and a variant of Default logic - Prioritised Default logic - is presented. We also pursue an investigation into the relationship between default reasoning and making inferences in a neural network. The inference problem shifts from the logical problem in Default logic to the optimisation problem in neural networks, in which maximum consistency is aimed at The inference is realised as an adaptation process that identifies and resolves conflicts between existing knowledge about the relevant world and external information. Knowledge and data are transformed into constraint equations and the nodes in the network represent propositions and constraint equations. The violation of constraints is formulated in terms of an energy function. The Hopfield network is shown to be suitable for modelling optimisation problems and default reasoning.Computer ScienceM.Sc. (Computer Science

    Learning to program, learning to teach programming: pre- and in service teachers' experiences of an object-oriented language

    Get PDF
    The quest for a better way to learn and teach programming, in particular object-oriented programming, is a challenge that continues to intrigue computer science educators. Even after decades of research in learning to program, educators still search for the optimal instructional approach that will solve the `learning to program effectively' problem among introductory programming students. The aim of this study was to gain insight into, and to suggest possible explanations for, the "qualitatively different ways" in which students experience learning to program using an object-oriented programming language, and to recommend teaching and learning strategies as a result of the outcomes of the research. In order to achieve these aims, a combination of phenomenographic research methods and elements of activity theory have been employed to gain an in depth understanding of pre- and in-service teachers' learning experiences. The categories of description for the phenomenon, learning to program and the influence of the learning context have been analysed and described in detail. It is argued that understanding learning to program using Java, in order to teach programming involves more than understanding learning to program as it is normally taught in university programming courses. In addition to object-oriented concepts such as message passing, inheritance, polymorphism, delegation and overriding, it entails understanding how learning to program is reflected in the goals of instruction and in different instructional practices. Knowledge of learning to program must also be linked to knowledge of students' thinking, so that teachers have conceptions of typical trajectories of student learning, and can use this knowledge to recognize landmarks of understanding in individuals. The findings suggest relationships among students' affective appraisals of the value of learning to program, their conceptions of learning to program, their approaches to learning it, their evaluations of their performance in tests and examinations and outcomes of their actions. The relationships emerged from student descriptions of their actions and the way in which different aspects of their learning and outcomes related to one another were qualitatively described and in some cases, quantified. In particular, the tensions between prior programming knowledge of a procedural language and current learning of an object-oriented language have emerged in the study. This has implications for teaching, as this study was set against the backdrop of the change in programming language in high schools, from a procedural to an object-oriented language.Mathematical SciencesPhD (Maths, Science and Technology Education

    European white paper : oropharyngeal dysphagia in head and neck cancer

    Get PDF
    Purpose To develop a European White Paper document on oropharyngeal dysphagia (OD) in head and neck cancer (HNC). There are wide variations in the management of OD associated with HNC across Europe. Methods Experts in the management of specific aspects of OD in HNC across Europe were delegated by their professional medical and multidisciplinary societies to contribute to this document. Evidence is based on systematic reviews, consensus-based position statements, and expert opinion. Results Twenty-four sections on HNC-specific OD topics. Conclusion This European White Paper summarizes current best practice on management of OD in HNC, providing recommendations to support patients and health professionals. The body of literature and its level of evidence on diagnostics and treatment for OD in HNC remain poor. This is in the context of an expected increase in the prevalence of OD due to HNC in the near future. Contributing factors to increased prevalence include aging of our European population (including HNC patients) and an increase in human papillomavirus (HPV) related cancer, despite the introduction of HPV vaccination in various countries. We recommend timely implementation of OD screening in HNC patients while emphasizing the need for robust scientific research on the treatment of OD in HNC. Meanwhile, its management remains a challenge for European professional associations and policymakers.Peer reviewe

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

    Get PDF
    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

    Canagliflozin and renal outcomes in type 2 diabetes and nephropathy

    Get PDF
    BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to <90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], >300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years

    Acknowledgement to reviewers of informatics in 2018

    Get PDF
    corecore