Optimisation de ľefficacité de couplage entre un guide ďonde confiné et une fibre optique monomode par ľintermédiaire ďune lentille boule

Theoretical coupling efficiency between a channel waveguide and a single-mode optical fibre using a ball lens is optimized by varying the parameters of the optical system such as the relative position of the components, the refractive index and the size of the lens. A specific software has been used for the optimization. Numerical calculations have been done under the Gaussian approximation of the fields distributions. The losses due to waveguides misalignments with respect to their ideal position have been evaluated. All these theoretical results are compared with those obtained from buttcoupling.     

Numerical modelling for simulation and treatment planning of prostate thermal therapy

A 2D transmission line matrix model is used to study thermal transfer in living tissues exposed to laser energy. Damage size because of thermal coagulation in thermal treatment of benign prostate hyperplasia is determined quantitatively. Results show a quasilinear dependency of blood perfusion on temperature at the beginning of coagulation. Immediately thereafter, blood perfusion decreases considerably until it shuts down when the tissue under investigation has been coagulated. Increase in perfusion rate (ω) leads to high values of t₁₀₀, which is the time required to reach a primary zone temperature of about 100 °C, and reflects the increased cooling created by perfusion. The transmission line matrix numerical model predicts the coagulation damage contours; that way, it has a clinical interest in therapy as an aid for clinicians because damage cannot be easily measured within patients. Results are validated through comparison with other researches. Copyright © 2014 John Wiley & Sons, Ltd.     

Characterisation of an algerian asphaltene by 1H and 13C CPMAS NMR,DEPT and ESI mass spectroscopy

Quantitative liquid 1H and solid 13C CPMAS NMR spectroscopy were used in combination with qualitative DEPT (Distortionless Enhancement by Polarization Transfer) and liquid 13C NMR to investigate the molecular structural parameters of an Algerian asphaltenes. The molecular weight of the asphaltene ionisable species determined by positive Electro Spray Ionization mass spectrometry ESI was around 390 Da. The results indicate that the representative molecular structure of the asphaltenes contains PAH (Poly-aromatic hydrocarbon) core of 4–5 rings. The combination of 13C NMR/DEPT constitutes a good route for characterizing the chemical functions of asphaltenes.     

Multi-layer compression algorithm for 3D deformed mesh based on multi library wavelet neural network architecture

Multimedia Tools and Applications - We propose in this paper a 3D mesh compression algorithm for 3D deformation objects to facilitate the transmission of deformed object to another. This algorithm...     

A novel approach for high dimension 3D object representation using Multi-Mother Wavelet Network

In this paper, we present a novel approach for 3D objects representation. Our idea is to prove that wavelet networks are capable for reconstruction and representing irregular 3D objects used in computer graphics. The major contribution consist to transform an input surface vertices into signals and to provide instantaneously an estimation of the output values for input values. To prove this, we will use a new structure of wavelet network founded on several mother wavelet families. This structure uses several mother wavelet, in order to maximize best wavelet selection probability. An algorithm to construct this structure is presented. First, Data is taken from 3D object. The vertices and their corresponding normal values of a 3D object are used to create a training set. To this stage, the training set can be expressed according to three functions, which interpolates all their vertices. Second we approximate each function using wavelet network. To achieve a better approximation, the network is trained several iterations to optimize wavelet selection for every mother. To guarantee a small error criterion, we adjust wavelet network parameters (weight, translation and dilation) by using an improved Orthogonal Least Squares method version. We consider our proposed approach on some 3D examples to prove that the new approach is able to approximate 3D objects with a good approximation ability.     

Retama raetam W: a poisonous plant of North Africa

A through-the-scope endoscopic balloon dilatation technique and acid-reducing medication was used in 46 consecutive patients (median age, 55; range, 21-88 years) with benign gastric outlet obstruction. In five patients, dilatation was not technically possible. In 41 patients, 122 dilatations (median, 2; range, 1-9 per patient) were performed without morbidity. Ninety-four procedures were successful (77%) at the initial attempt (able to pass a 12-mm endoscope into the duodenum at the end of the procedure). Median follow-up in the 41 patients was 19 (range, 1-78) months. Thirteen patients (32%) required subsequent surgery; 8 had delayed operation for persistent symptoms (1-28 months after the first dilatation), 1 had surgery during the initial hospital admission, and 4 required emergency surgery for other ulcer complications (3 perforation, 1 bleeding). Of the 28 patients who had only balloon dilatation and medical therapy, 11 are asymptomatic (4 with active ulceration), 9 have mild symptoms (Visick 2), and 3 have persistent symptoms (Visick 3). One patient was lost to follow-up and four patients have died (one from an ulcer-related complication). Balloon dilatation and sustained acid-reducing therapy with regular endoscopic surveillance should be first-line treatment of peptic pyloroduodenal strictures, because the procedure is safe and is likely to be successful in half of the patients in whom dilatation is technically possible.