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Exploring Machine Learning Methods to Automatically Identify Students in Need of Assistance
Get PDFABSTRACT Methods for automatically identifying students in need of assistance have been studied for decades. Initially, the work was based on somewhat static factors such as students' educational background and results from various questionnaires, while more recently, constantly accumulating data such as progress with course assignments and behavior in lectures has gained attention. We contribute to this work with results on early detection of students in need of assistance, and provide a starting point for using machine learning techniques on naturally accumulating programming process data. When combining source code snapshot data that is recorded from students' programming process with machine learning methods, we are able to detect high-and low-performing students with high accuracy already after the very first week of an introductory programming course. Comparison of our results to the prominent methods for predicting students' performance using source code snapshot data is also provided. This early information on students' performance is beneficial from multiple viewpoints. Instructors can target their guidance to struggling students early on, and provide more challenging assignments for high-performing students. Moreover, students that perform poorly in the introductory programming course, but who nevertheless pass, can be monitored more closely in their future studies
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No full textAbstract The objective of this study is to determine the relation of inhabitants of Centra
NEW TECHNIQUE FOR SKEW ANGLE DETECTION OF TEXT IN IMAGE DOCUMENT
Get PDFAbstract Image text document can be acquire via scanner or other type of machines which cause sometime a skew angle (alignment) on its horizontal direction so many techniques were developed to treat that skew. In This Research a new idea based on Fan filter will be achieved to detect the skew angle of a text image. A fan filter will be designed in different level and size to be suitable to decompose the image to its component with the same number of filter level, then looking for which coefficients hold the highest energy. The skew angle of the text image will be extracted from The fan filter component rank which match the highest energy component in the image slices. The proposed algorithm applied on different type of skew with different images. The difference between the measured angle and the actual angle in the range of ± 1.5º. the proposed algorithm was simulated using Matlab software Version (R2011a)
Work supported in part by Department of Energy contract DE-AC02-76SF00515 Study of B → D ( * ) D Decays and Measurement of D − s and D sJ (2460) − Branching Fractions
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No full textAbstract. An investigation was made of changes in the Raman spectra of germanosilicate optical fibres as a result of UV irradiation. The photoinduced changes in the spectra were of the same nature for all types of irradiation used. These changes increased with increase in the radiation dose and in the GeO 2 concentration in the fibre core and were evidence of a structural modification of glass. Introduction Photoinduced modification of the refractive index of germanosilicate glasses plays an important role in the development of a new class of integrated-optical and optical-fibre instruments and devices (see, for example, Ref. One of the proposed mechanisms of this effect is the transformation of GOD centres giving rise to other defects [GeE H , Ge(1), Ge(2), DID] in the glass as a result of UV irradiation À3 [5]. Such a large change is most likely associated with the experimentally observed increase in the density of glass as a result of the action of high-intensity UV radiation from pulsed lasers or of low-intensity UV radiation from cw lasers One of the methods for investigating the microstructure of glasses is the Raman scattering of light, which makes it possible to use the positions and intensities of the bands in the Raman spectra to study the vibrational spectra associated directly with the glass structure. In Ref. [6] it was shown for the first time that exposure of a germanosilicate optical fibre to powerful pulsed excimer laser radiation of the 248 nm wavelength alters considerably the Raman spectra. According to Ref. [6], these changes are evidence of a considerable photoinduced modification of the microstructure of the glass shown by a reduction in the number of multimember (six members or more) rings consisting of SiO 4 tetrahedra and an increase in the number of rings with few members in the glass structure. Since only one radiation dose (41 kJ cm À2 ) was used Our aim was to study the UV-induced changes in the Raman spectra of germanosilicate optical fibres as a function of the concentration of germanium dioxide in the fibre core, and also of the UV dose and of the kind of irradiation. Experiments The Raman spectra of fibres were recorded, as in Ref. Optical fibres with a germanosilicate core and a cladding made of pure fused silica, free of any additional dopants, were made by the modified chemical vapour deposition method. The parameters of the investigated fibres are liste
Generating Moving Average Trading Rules on the Oil Futures Market with Genetic Algorithms
No full textThe crude oil futures market plays a critical role in energy finance. To gain greater investment return, scholars and traders use technical indicators when selecting trading strategies in oil futures market. In this paper, the authors used moving average prices of oil futures with genetic algorithms to generate profitable trading rules. We defined individuals with different combinations of period lengths and calculation methods as moving average trading rules and used genetic algorithms to search for the suitable lengths of moving average periods and the appropriate calculation methods. The authors used daily crude oil prices of NYMEX futures from 1983 to 2013 to evaluate and select moving average rules. We compared the generated trading rules with the buy-and-hold (BH) strategy to determine whether generated moving average trading rules can obtain excess returns in the crude oil futures market. Through 420 experiments, we determine that the generated trading rules help traders make profits when there are obvious price fluctuations. Generated trading rules can realize excess returns when price falls and experiences significant fluctuations, while BH strategy is better when price increases or is smooth with few fluctuations. The results can help traders choose better strategies in different circumstances
Københavns Universitet Presence of psychoactive substances in oral fluid from randomly selected drivers in Presence of psychoactive substances in oral fluid from randomly selected drivers in Denmark
No full textKnowledge, Attitude and Practices Of School Children and Teachers Of Khammam towards Oral Hygiene Knowledge, Attitude and Practices Of School Children and Teachers Of Khammam towards Oral Hygiene
No full textAbstract Objectives: This study was conducted to assess the knowledge,attitude and practices of school children and school teachers towards oral hygiene, oral health and also to assess the dentition status in school children in rural and urban areas of Khammam. Materials and methods: In the present study 700school students of age group 9-15 years and 100 teachers were included.data on oral health KAP from school students and teachers were collected by giving a close ended questionnaire consisting of 24 and 31 pre tested questions respectively