119 research outputs found
LE COEFFICIENT DâOCCUPATION DU SOL COS ET LA PROMOTION DES TECHNIQUES MODERNES DE LA GESTION URBAINE -CAS DE LA VILLE DâALGER
Les systĂšmes traditionnels de contrĂŽle de la densitĂ©, lors de lâĂ©tablissement du Plan Directeur dâAmĂ©nagement et dâUrbanisme(PDAU) et le Plan dâOccupation du Sols (POS) dont la responsabilitĂ© communale sâexerce, imposent des innovations rapideset fondamentales des techniques modernes de gestion urbaine.Partie intĂ©grante du POS, le coefficient dâoccupation du sol (COS) reprĂ©sente une rĂšgle axiale pour les nouveaux outilsdâurbanisme, il est donc lâĂ©lĂ©ment de base du rĂšglement dâurbanisme.Lâobjet de ce travail est la mise au point dâune mĂ©thode thĂ©orique et analytique du COS, qui met en Ă©vidence ses facteursdĂ©terminants et sa relation avec les espaces fonctionnels de lâhabitat. Ce travail sâintĂ©resse surtout Ă lâĂ©quilibre entre larĂ©glementation concernant le coefficient dâoccupation du sol et son application. Câest une phase importante pour la poursuitedes empreintes et des effets du COS dans la rĂ©alitĂ©,Le travail se termine par un modĂšle dâintĂ©gration informatisĂ©e qui met en reliefs ces relations et leurs interactions.Mots clĂ©s : AlgĂ©rie â AlgerâDensitĂ©âCoefficient dâoccupation des sols COS-Droit de lâurbanisme-Techniques de gestionurbaine-Programme COS
Long-time Behavior of a Two-layer Model of Baroclinic Quasi-geostrophic Turbulence
We study a viscous two-layer quasi-geostrophic beta-plane model that is
forced by imposition of a spatially uniform vertical shear in the eastward
(zonal) component of the layer flows, or equivalently a spatially uniform
north-south temperature gradient. We prove that the model is linearly unstable,
but that non-linear solutions are bounded in time by a bound which is
independent of the initial data and is determined only by the physical
parameters of the model. We further prove, using arguments first presented in
the study of the Kuramoto-Sivashinsky equation, the existence of an absorbing
ball in appropriate function spaces, and in fact the existence of a compact
finite-dimensional attractor, and provide upper bounds for the fractal and
Hausdorff dimensions of the attractor. Finally, we show the existence of an
inertial manifold for the dynamical system generated by the model's solution
operator. Our results provide rigorous justification for observations made by
Panetta based on long-time numerical integrations of the model equations
Parallel Evaluation of Multi-join Queries
A number of execution strategies for parallel evaluation of multi-join queries have been proposed in the literature. In this paper we give a comparative performance evaluation of four execution strategies by implementing all of them on the same parallel database system, PRISMA/DB. Experiments have been done up to 80 processors. These strategies, coming from the literature, are named: Sequential Parallel, Synchronous Execution, Segmented Right-Deep, and Full Parallel. Based on the experiments clear guidelines are given when to use which strategy.
This is an extended abstract; the full paper appeared in Proc. ACM SIGMOD'94, Minneapolis, Minnesota, May 24â27, 199
Contribution Ă la modĂ©lisation du flux de phosphore dans le barrage de Hammam Boughrara (province de Tlemcen, AlgĂ©rie) : application Ă la gestion de lâeutrophisation
Dans la prĂ©sente Ă©tude portant sur le barrage de Hammam Boughrara, mis en eau en 1999, nous avons appliquĂ© plusieurs modĂšles de bilan du phosphore, Ă savoir les modĂšles de Vollenweider (1969), de Dillon & Rigler (1975), de Walker (1977), de Reckhow (1977) et dâOstrofsky (1978). Afin de prendre en considĂ©ration la vitesse de submersion graduelle des surfaces inondĂ©es, caractĂ©risĂ©e ordinairement par un accroissement trĂšs important de lâĂ©tat trophique rĂ©sultant des apports endogĂšnes du phosphore par lessivage, nous avons tentĂ© dâadapter le modĂšle dâOstrofsky (1978) Ă la rĂ©alitĂ© du rĂ©servoir Ă©tudiĂ©, et ce en ajoutant une nouvelle dimension. Les rĂ©sultats obtenus montrent que le modĂšle proposĂ© semble pertinent.In the present study, carried out on the Hammam Boughrara dam (impounded in 1999), a number of phosphorus balance models were applied, namely, Vollenweider (1969), Dillon & Rigler (1975), Walker (1977), Reckhow (1977) and Ostrofsky (1978) models. In order to take into account the rate of gradual submergence of flooded surfaces which is ordinarily characterized by an important increase in the trophic status as a result of endogenous inputs of phosphorus by leaching we have tried to adapt the Ostrofsky model (1978) to the reality of studied dam, by adding a new dimension. The obtained results show that the proposed model seems relevant
Serotypes and Antibiotic Susceptibility of Streptococcus pneumoniae Isolates from Invasive Pneumococcal Disease and Asymptomatic Carriage in a Pre-vaccination Period, in Algeria
In Algeria, few data is available concerning the distribution of pneumococcal serotypes and respective antibiotic resistance for the current pre-vaccination period, which is a public health concern. We identified the most frequent Streptococcus pneumoniae serogroup/types implicated in invasive pneumococcal disease (IPD; n = 80) and carriage (n = 138) in Algerian children younger than 5 years old. Serogroup/types of 78 IPD isolates were identified by capsular typing using a sequential multiplex PCR. Overall, serotypes 14, 19F, 6B, 23F, 18C, 1, 5, 7F, 19A, and 3 (55% of PCV7 serotypes, 71.3% of PCV10, and 90% of PCV13) were identified. Additionally, 7.5% of the non-vaccine serotypes 6C, 9N/L, 20, 24F, 35B, and 35F, were observed. In the case of S. pneumoniae asymptomatic children carriers, the most common serogroup/types were 6B, 14, 19F, 23F, 4, 9V/A, 1, 19A, 6A, and 3 (42.7% of PCV7 serotypes, 44.2% of PCV10, and 58% of PCV13). For 6.1% of the cases co-colonization was detected. Serotypes 14, 1, 5, and 19A were more implicated in IPD (p 2ÎŒg/ml). Resistance to cefotaxime was higher in isolates from meningitis (40.5%); however, resistance to erythromycin and co-trimoxazole (>40%) was more pronounced in no-meningeal forms. Overall, our results showed that PCV13 conjugate vaccine would cover up to 90% of the circulating isolates associated with IPD in Algeria, highlighting the importance of monitoring the frequency of S. pneumoniae serogroups/types during pre- and post-vaccination periods
In silico pharmacodynamics, toxicity profile and biological activities of the Saharan medicinal plant Limoniastrum feei
ABSTRACT In-silico study was performed to find the pharmacodynamics, toxicity profiles and biological activities of three phytochemicals isolated from Limoniastrum feei (Plumbagenaceae). Online pharmacokinetic tools were used to estimate the potential of Quercetin, kaempferol-3-O-ÎČ-D-glucopyranoside (astragalin) and quercitin-7-O-ÎČ-D-glucopyranoside as specific drugs. Then the prediction of potential targets of these compounds were investigated using PharmMapper. Auto-Dock 4.0 software was used to investigate the different interactions of these compounds with the targets predicted earlier. The permeability of quercetin was found within the range stated by Lipinski Śłs rule of five. Hematopoietic prostaglandin (PG) D synthase (HPGDS), farnesyl diphosphate synthetase (FPPS) and the deoxycytidine kinase (DCK) were potential targets for quercetin, astragalin and quercetin 7, respectively. Quercetin showed antiallergic and anti-inflammatory activity, while astragalin and quercetin 7 were predicted to have anticancer activities. The activity of Astragalin appeared to be mediated by FPPS inhibition. The inhibition of DCK was predicted as the anticancer mechanisms of quercetin 7. The compounds showed interesting interactions and satisfactory binding energies when docked into their targets. These compounds are proposed to have activities against a variety of human aliments such as allergy, tumors, muscular dystrophy, and diabetic cataracts
Formulation and Optimization by Experimental Design of Low-Fat Mayonnaise Based on Soy Lecithin and Whey
The main objective of this study is to develop a new formula for a diet mayonnaise-like sauce without cholesterol. Emulsifying power is provided by the use of soy lecithin and the total fat content was limited to 16%. Droplet size measurement of employed mayonnaise samples at different times show that the largest diameter of fat does not exceed 18.5 ”m with a yield stress of 56.1 Pa. Results of stability to centrifugation reveal that the absence of the supernatant oily layer ensures the stability of the emulsion. Using the experimental design method, the number of trials can be limited to a number of 16 experiments, and best formulation of the mayonnaise (without cholesterol) was obtained
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