Caractérisation de textures à l'aide d'un codage directionnel local

Texture characterisation with a local directional codingIn this paper, we propose a texture characterisation method based on a coding of the local structure of the texture. The local information in four  directions around a pixel is represented by a local directional code, which is the association of four directional elementary codes. The construction of four directional matrices allows computing efficient texture features for texture characterisation. Classification with 24 Brodatz textures and segmentation experiments show interesting perspectives for this method, which is related to texture unit method

Facility and community results-based financing to improve maternal and child nutrition and health in The Gambia

In 2013, the Government of The Gambia implemented a novel results-based financing (RBF) intervention designed to improve maternal and child nutrition and health through a combination of community, facility and individual incentives. In a mixed-methods study, we used a randomized 2 x 2 study design to measure these interventions' impact on the uptake of priority maternal health services, hygiene and sanitation. Conditional cash transfers to individuals were bundled with facility results-based payments. Community groups received incentive payments conditional on completion of locally-designed health projects. Randomization occurred separately at health facility and community levels. Our model pools baseline, midline and endline exposure data to identify evidence of the interventions' impact in isolation or combination. Multivariable linear regression models were estimated. A qualitative study was embedded, with data thematically analyzed. We analyzed 5,927 household surveys: 1,939 baseline, 1,951 midline, and 2,037 endline. On average, community group interventions increased skilled deliveries by 11 percentage points, while the facility interventions package increased them by seven percentage points. No impact was found, either in the community group or facility intervention package arms on early ANC. The community group intervention led to 49, 43 and 48 percentage point increases in handwashing stations, soaps at station and water at station, respectively. No impact was found on improved sanitation facilities. The qualitative data help understand factors underlying these changes. No interaction was found between the community and facility interventions. Where demand-side barriers predominate and community governance structures exist, community group RBF interventions may be more effective than facility designs

Carbone des sols en Afrique

Les sols sont une ressource essentielle à préserver pour la production d’aliments, de fibres, de biomasse, pour la filtration de l’eau, la préservation de la biodiversité et le stockage du carbone. En tant que réservoirs de carbone, les sols sont par ailleurs appelés à jouer un rôle primordial dans la lutte contre l’augmentation de la concentration de gaz à effet de serre. Ils sont ainsi au centre des objectifs de développement durable (ODD) des Nations unies, notamment les ODD 2 « Faim zéro », 13 « Lutte contre le changement climatique », 15 « Vie terrestre », 12 « Consommation et production responsables » ou encore 1 « Pas de pauvreté ». Cet ouvrage présente un état des lieux des sols africains dans toute leur diversité, mais au-delà, il documente les capacités de stockage de carbone selon les types de sols et leurs usages en Afrique. Il propose également des recommandations autour de l’acquisition et de l’interprétation des données, ainsi que des options pour préserver, voire augmenter les stocks de carbone dans les sols. Tous les chercheurs et acteurs du développement impliqués dans les recherches sur le rôle du carbone des sols sont concernés par cette synthèse collective. Fruit d’une collaboration entre chercheurs africains et européens, ce livre insiste sur la nécessité de prendre en compte la grande variété des contextes agricoles et forestiers africains pour améliorer nos connaissances sur les capacités de stockage de carbone des sols et lutter contre le changement climatique

Multiresolution texture feature extraction based on pyramid wavelet decomposition

No Abstract. Global Journal of Pure and Applied Sciences Vol. 12(3) 2006: 409-41

CARI'96 : actes du 3ème colloque africain sur la recherche en informatique = CARI'96 : proceedings of the 3rd African conference on research in computer science

Dans cet article, nous présentons une méthode de segmentation hiérarchique de textures fondée sur une décomposition en ondelettes de l'image. Une segmentation grossière est effectuée au niveau de résolution le plus élevé à partir de prototypes de chaque classe de texture déterminés avec un classificateur flou. Une analyse de voisinage permet ensuite de créer une classe de pixels ambigus. La segmentation initiale est progressivement affinée en reportant la prise de décision pour les pixels ambigus au niveau de résolution de l'image originale. (Résumé d'auteur

Robust decoupling controland extended sliding mode observer for an induction motor

ISSN 1114-3800International audienceThis paper presents a feedback linearization strategy and a robust controller to permit a decoupling and regulation of the motor states in order to assure a good dynamic performance and stability of the global system. As the control required the knowledge of the instantaneous flux of the rotor and the rotor parameter estimation can improve the control quality, a fifth-order discrete-time extended sliding mode observer is proposed for on-line estimation of rotor fluxes and rotor time constant. The simulation and experimental results for a 5.5 kW induction motor are presented to illustrate the validity and the high robustness of the proposed approach against parameter variations and disturbances

Bayonet-shaped language development in autism with regression: a retrospective study.

Language delay is one of the major referral criteria for an autism evaluation. Once an autism spectrum diagnosis is established, the language prognosis is among the main parental concerns. Early language regression (ELR) is observed by 10-50% of parents but its relevance to late language level and socio-communicative ability is uncertain. This study aimed to establish the predictive value of ELR on the progression of language development and socio-communicative outcomes to guide clinicians in addressing parents' concerns at the time of diagnosis. We used socio-communicative, language, and cognitive data of 2,047 autism spectrum participants from the Simons Simplex Collection, aged 4-18 years (mean = 9 years; SD = 3.6). Cox proportional hazard and logistic regression models were used to evaluate the effect of ELR on language milestones and the probability of using complex and flexible language, as defined by the choice of ADOS module at enrollment. Linear models were then used to evaluate the relationship of ELR and non-verbal IQ with socio-communicative and language levels. ELR is associated with earlier language milestones but delayed attainment of fluent, complex, and flexible language. However, this language outcome can be expected for almost all autistic children without intellectual disability at 18 years of age. It is mostly influenced by non-verbal IQ, not ELR. The language and socio-communicative level of participants with flexible language, as measured by the Vineland and ADOS socio-communicative subscales, was not affected by ELR. This study is based on a relatively coarse measure of ultimate language level and relies on retrospective reporting of early language milestones and ELR. It does not prospectively document the age at which language catches up, the relationship between ELR and other behavioral areas of regression, nor the effects of intervention. For autistic individuals with ELR and a normal level of non-verbal intelligence, language development follows a "bayonet shape" trajectory: early first words followed by regression, a plateau with limited progress, and then language catch up

Community-directed vector control to supplement mass drug distribution for onchocerciasis elimination in the Madi mid-North focus of Northern Uganda.

BACKGROUND:Onchocerciasis a neglected tropical disease that historically has been a major cause of morbidity and an obstacle to economic development in the developing world. It is caused by infection with Onchocerca volvulus, which is transmitted by black flies of the genus Simulium. The discovery of the potent effect of Mectizan (ivermectin) on O. volvulus microfilariae and the decision by its manufacturer to donate the drug for onchocerciasis spurred the implementation of international programs to control and, more recently, eliminate this scourge. These programs rely primarily on mass distribution of ivermectin (MDA) to the afflicted populations. However, MDA alone will not be sufficient to eliminate onchocerciasis where transmission is intense and where ivermectin MDA is precluded by co-endemicity with Loa loa. Vector control will likely be required as a supplemental intervention in these situations. METHODOLOGY/PRINCIPAL FINDINGS:Because biting by the black fly vectors is often a major nuisance in onchocerciasis afflicted communities, we hypothesized that community members might be mobilized to clear the breeding sites of the vegetation that represents the primary black fly larvae attachment point. We evaluated the effect of such a community based "slash and clear" intervention in multiple communities in Northern Uganda. Slash and Clear resulted in 89-99% declines in vector biting rates. The effect lasted up to 120 days post intervention. CONCLUSIONS/SIGNIFICANCE:Slash and clear might represent an effective, inexpensive, community- based tool to supplement ivermectin distribution as a contributory method to eliminate onchocerciasis and prevent recrudescence