Arabic Spelling Correction using Supervised Learning

In this work, we address the problem of spelling correction in the Arabic language utilizing the new corpus provided by QALB (Qatar Arabic Language Bank) project which is an annotated corpus of sentences with errors and their corrections. The corpus contains edit, add before, split, merge, add after, move and other error types. We are concerned with the first four error types as they contribute more than 90% of the spelling errors in the corpus. The proposed system has many models to address each error type on its own and then integrating all the models to provide an efficient and robust system that achieves an overall recall of 0.59, precision of 0.58 and F1 score of 0.58 including all the error types on the development set. Our system participated in the QALB 2014 shared task "Automatic Arabic Error Correction" and achieved an F1 score of 0.6, earning the sixth place out of nine participants.Comment: System description paper that is submitted in the EMNLP 2014 conference shared task "Automatic Arabic Error Correction" (Mohit et al., 2014) in the Arabic NLP workshop. 6 page

Acceleration Techniques for Photo Realistic Computer Generated Integral Images

The research work presented in this thesis has approached the task of accelerating the generation of photo-realistic integral images produced by integral ray tracing. Ray tracing algorithm is a computationally exhaustive algorithm, which spawns one ray or more through each pixel of the pixels forming the image, into the space containing the scene. Ray tracing integral images consumes more processing time than normal images. The unique characteristics of the 3D integral camera model has been analysed and it has been shown that different coherency aspects than normal ray tracing can be investigated in order to accelerate the generation of photo-realistic integral images. The image-space coherence has been analysed describing the relation between rays and projected shadows in the scene rendered. Shadow cache algorithm has been adapted in order to minimise shadow intersection tests in integral ray tracing. Shadow intersection tests make the majority of the intersection tests in ray tracing. Novel pixel-tracing styles are developed uniquely for integral ray tracing to improve the image-space coherence and the performance of the shadow cache algorithm. Acceleration of the photo-realistic integral images generation using the image-space coherence information between shadows and rays in integral ray tracing has been achieved with up to 41 % of time saving. Also, it has been proven that applying the new styles of pixel-tracing does not affect of the scalability of integral ray tracing running over parallel computers. The novel integral reprojection algorithm has been developed uniquely through geometrical analysis of the generation of integral image in order to use the tempo-spatial coherence information within the integral frames. A new derivation of integral projection matrix for projecting points through an axial model of a lenticular lens has been established. Rapid generation of 3D photo-realistic integral frames has been achieved with a speed four times faster than the normal generation

Bioinsecticide activity of Bacillus thuringiensis isolates on tomato borer, Tuta absoluta (Meyrick) and their molecular identification

Twelve (12) bacterial isolates were isolated from dead larvae of Tuta absoluta (4th instar) from tomato cultivated fields at Fayoum Governorate, Egypt. All isolates were preliminarily identified as members of the genus Bacillus based on morphological and biochemical characteristics. According to the results of the pathogenicity of Bacillus isolates against different larval instars of T. absoluta, the 12 isolates revealed varying efficiencies and the isolates B1, B2, B3 and B4 showed high mortality of 93.3, 90, 86.7 and 80% on day 7, respectively, on the 4th instar larvae. Also, protecto (Bacillus thuringiensis subsp. kurstaki) recorded the highest mortality when the 4th instar larvae were treated with 2 g / 2 liter of water (96.7%) on the 5th day post treatment. Isolate B12 recorded the lowest percentage mortality of the 4th instar larvae (13.3%). In addition, there was a significant decrease in egg hatching percentage reaching 44.12% compared with the control, meanwhile, the adult emergence decreased after treatment and only 38 and 30 adults emerged from the cages containing tomato plants infested by eggs with B1 and protecto compared with the control which gave 253 adults that emerged. Further, genetic identification of 12 isolates was performed using randomly amplified poylmorphic DNA (RAPD) markers to determine their genetic diversity pattern. Different random primers were used for RAPD amplification, which generated a total of 52 fragments; of these 42 were polymorphic and 10 monomorphic. The primers OPA02, OPA04, and OPA07 produced 100% polymorphic fragments, whereas primers OPA1, OPA3, OPA05, OPA06, OPA08 and OPA09 produced 1, 3, 1, 2, 1 and 2 monomorphic fragments, respectively. When the RAPD banding pattern data was subjected to dendrogram construction, the 4 isolates fell into two separate clusters, clusters I cluster II, which includes 1 and 3 B. thuringiensis isolates, respectively. The RAPD technique was shown to be effective in differentiating closely related isolates and applied to confirm the identification of Bacillus isolates by API system which was used to reveal the phylogenetic relationships between the isolates.Keywords: Bacillus thuringiensis, bioinsecticide, randomly amplified poylmorphic DNA-polymerase chain reaction (RAPD-PCR), instar larvae, Tuta absolutaAfrican Journal of Biotechnology Vol. 12(23), pp. 3699-370

Convergence des EDSRs et homogéneisation des inégalités variationnelles semilinéaires dans un convexe

AbstractWe study the limit of the solution of a Semi-linear Variational Inequality (SVI for short) involving a second order differential operator of parabolic type with periodic coefficients and highly oscillating term. Our basic tool is the approach given by Pardoux [16]. In particular, we use the weak convergence of an associated reflected Backward Stochastic Differential Equation (BSDE for short)

Non-dominated sorting gravitational search algorithm for multi-objective optimization of power transformer design

Transformers are crucial components in power systems. Due to market globalization, power transformer manufacturers are facing an increasingly competitive environment that mandates the adoption of design strategies yielding better performance at lower mass and losses. Multi-objective Optimization Problems (MOPs) consist of several competing and incommensurable objective functions. Recently, as a search optimization technique inspired by nature, evolutionary algorithms have been broadly applied to solve MOPs. In this paper, a power Transformer Design (TD) methodology using Non-dominated Sorting Gravitational Search Algorithm (NSGSA) is proposed. Results are obtained and presented for NSGSA approach. The obtained results for the study case are compared with those results obtained when using other multi objective optimization algorithms which are Novel Gamma Differential Evolution (NGDE) Algorithm, Chaotic Multi-Objective Algorithm (CMOA), and Multi- Objective Harmony Search (MOHS) algorithm. From the analysis of the obtained results, it has been concluded that NSGSA algorithm provides the most optimum solution and the best results in terms of normalized arithmetic mean value of two objective functions using NSGSA to the TD optimization

Geotechnical properties of paper recycling waste streams

This paper studies two waste streams of the paper recycling industry for potential use in geotechnical applications. Namely, de-inking paper sludge from the secondary treatment stage, and paper sludge ash (PSA) obtained from the incineration of this sludge. Salient geotechnical properties of the statically compacted sludge before and after stabilisation with lime or PSA are presented. Tests include shear box testing, uniaxial compressive strength (UCS) testing, 1-D swelling and compression in oedometric conditions, p-wave velocity measurements using a Portable Ultrasonic Non-destructive Digital Indicating Tester (PUNDIT), and filter paper testing to determine water retention characteristics. The volume changes of the untreated sludge were found to be considerable in all above tests; however its shear strength at a highly compacted state was overall adequate. Chemical stabilization of the sludge was effective in reducing volume changes. The PSA was also assessed as a silt soil stabiliser. As geomaterial stabiliser, PSA was found to have a similar or better performance than lime. Overall the results are encouraging and indicate that it is possible to use paper industry waste in geotechnical applications