Arabic parsing using grammar transforms

We investigate Arabic Context Free Grammar parsing with dependency annotation comparing lexicalised and unlexicalised parsers. We study how morphosyntactic as well as function tag information percolation in the form of grammar transforms (Johnson, 1998, Kulick et al., 2006) affects the performance of a parser and helps dependency assignment. We focus on the three most frequent functional tags in the Arabic Penn Treebank: subjects, direct objects and predicates . We merge these functional tags with their phrasal categories and (where appropriate) percolate case information to the non-terminal (POS) category to train the parsers. We then automatically enrich the output of these parsers with full dependency information in order to annotate trees with Lexical Functional Grammar (LFG) f-structure equations with produce f-structures, i.e. attribute-value matrices approximating to basic predicate-argument-adjunct structure representations. We present a series of experiments evaluating how well lexicalized, history-based, generative (Bikel) as well as latent variable PCFG (Berkeley) parsers cope with the enriched Arabic data. We measure quality and coverage of both the output trees and the generated LFG f-structures. We show that joint functional and morphological information percolation improves both the recovery of trees as well as dependency results in the form of LFG f-structures

Moving Object Trajectories Meta-Model And Spatio-Temporal Queries

In this paper, a general moving object trajectories framework is put forward to allow independent applications processing trajectories data benefit from a high level of interoperability, information sharing as well as an efficient answer for a wide range of complex trajectory queries. Our proposed meta-model is based on ontology and event approach, incorporates existing presentations of trajectory and integrates new patterns like space-time path to describe activities in geographical space-time. We introduce recursive Region of Interest concepts and deal mobile objects trajectories with diverse spatio-temporal sampling protocols and different sensors available that traditional data model alone are incapable for this purpose.Comment: International Journal of Database Management Systems (IJDMS) Vol.4, No.2, April 201

Transverse Hilbert Schemes and Completely Integrable Systems

Via the transverse Hilbert scheme construction, we associate a holomorphic completely integrable system to a surface $S$ endowed with a holomorphic symplectic form $\omega$ and a projection onto $\mathbb{C}$. We provide a full characterization of the completely integrable systems that arise in this way.Comment: 12 page

Hypoxia enhances the tissue protective effect of erythropoietin and its analogues in an endothelial cell injury model

PO has tissue protective activities in ischemic disease but also has prothrombotic, erythropoietic effects. Carbamylated EPO (CEPO) retains the protective actions without the erythropoietic effects. To assess the potential of these molecules in atherosclerosis (an ischemic heart disease), we investigated EPO and CEPO in an in vitro model of injury using bovine aortic endothelial cells (BAEC) in hypoxia and normoxia.. BAECs were grown to confluence in 10% FBS in 12 well culture plates. They were then cultured under normoxia (21% oxygen) or hypoxia (5% oxygen) 24 h prior to their use in an injury model using the ‘scratch assay.’ The effects of EPO and CEPO on endothelial closure were assessed using a range of concentrations (0-10 ng/mL). In separate experiments, the effects of EPO and CEPO on BAEC proliferation and chemotaxis were also assessed under similar hypoxic conditions. Gene expression of the receptors that may be involved in their protective pathway [EPOR and the β common chain receptor (βCR)] were assessed using quantitative PCR. The effects of both EPO and CEPO were enhanced under hypoxic conditions (13 ± 2.6 %, and 10 ± 1.69 %, p0.05). Whilst, the expression of EPOR gene increased by 2.1 ± 0.8 folds (p<0.05) In hypoxia, βCR expression was not affected by the change in oxygen tension. The effects of EPO and CEPO in the scratch assay appeared to be mediated by enhancing cell proliferation and migration of BAECs (p<0.05). In conclusion, the enhanced effects of EPO and CEPO on endothelial cells under hypoxia requires further investigation in processes in which hypoxia may play a role, e.gfor example. in atherogenesis and re-stensosis following angioplasty

Signal Processing Issues Related to Deterministic Sea Wave Prediction

The bulk of the research work in wave related areas considers sea waves as stochastic objects leading to wave forecasting techniques based on statistical approaches. Due to the complex dynamics of the sea waves’ behaviour, statistical techniques are probably the only viable approach when forecasting over substantial spatial and temporal intervals. However this view changes when limiting the forecasting time to a few seconds or when the goal is to estimate the quiescent periods that occur due to the beating interaction of the wave components, especially in narrow band seas. This work considers the multi disciplinary research field of deterministic sea wave prediction (DSWP), exploring different aspects of DSWP associated with shallow angle LIDAR systems. The main goal of this project is to study and develop techniques to reduce the prediction error. The first part deals with issues related to shallow angle LIDAR systems data problems, while the remaining part of this work concentrates on the prediction system and propagation models regardless of the source of the data. The two main LIDAR data problems addressed in this work are the non-uniform distribution and the shadow region problems. An empirical approach is used to identify the characteristics of shadow regions associated with different wave conditions and different laser position. A new reconstruction method is developed to address the non-uniformed sampling problem, it is shown that including more information about the geometry and the dynamics of the problem improves the reconstruction error considerably. The frequency domain approach to the wave propagation model is examined. The effect of energy leakage on the prediction error is illustrated. Two approaches are explored to reduce this error. First a modification of the simple dispersive phase shifting filter is tested and shown to improve the prediction. The second approach is to reduce the energy leakage with an iterative Window-Expansion method. Significant improvement of the prediction error is achieved using this method in comparison to the End-Matching method typically used in DSWP systems. The final part in examining the frequency domain approach is to define the prediction region boundaries associated with a given prediction accuracy. The second propagation model approach is the Time/Space domain approach. In this method the convolution of the measured data and the propagation filter impulse response is used in the prediction system. In this part of the research work properties of these impulse responses are identified. These are found to be quite complicated representations. The relation between the impulse response (duration and shift) with prediction time and distance are studied. Quantification of these impulse responses properties are obtained by polynomial approximation and non-symmetric filter analysis. A new method is shown to associate the impulse response properties to the prediction region of both the Fixed Time and Fixed Point mode

Three level Induction Motor Torque Control Schemes for Electric Vehicles application

Abstract- This work presents the results of an investigation into suitable torque control schemes for an electric vehicle application. The electric vehicle drive consists of rewound induction motors and a three-level IGBT inverter switching at 10 kHz. The schemes investigated are Direct Torque Control DTC with three-level IGBT inverter, and a new direct-torque fuzzy control (DTFC) scheme of induction motor with space vector modulation (SVM) is presented. The results of Matlab- Simulink simulations and a comparison between the control schemes are presented. It is found that the DTFC and space vector application using three-level IGBT is best for this application.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Removing bias due to finite measurement of dynamic systems: case study on P2P systems

Mesurer avec pr\'ecision la dynamique des graphes de terrain est une t\^ache difficile, car les propri\'et\'es observ\'ees peuvent \^etre biais\'ees pour diff\'erentes raisons, en particulier le fait que la p\'eriode de mesure soit finie. Dans ce papier, nous introduisons une m\'ethodologie g\'en\'erale qui nous permet de savoir si la fen\^etre d'observation est suffisamment longue pour caract\'eriser une propri\'et\'e donn\'ee dans n'importe quel syst\`eme dynamique. Nous appliquons cette m\'ethodologie \`a l'\'etude des dur\'ees de sessions et des dur\'ees de vie des fichiers sur deux jeux de donn\'ees P2P. Nous montrons que le comportement des propri\'et\'es est diff\'erent : pour les dur\'ees de sessions, notre m\'ethodologie nous permet de caract\'eriser avec pr\'ecision la forme de leur distribution. Par contre, pour les dur\'ees de vie des fichiers, nous montrons que cette propri\'et\'e ne peut pas \^etre caract\'eris\'ee, soit parce qu'elle n'est pas stationnaire, soit parce que la dur\'ee de notre mesure est trop courte