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Search Results: 1 - 10 of 142 matches for " Daouda Badiane "
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Analysis of Bushfires Spatial and Temporal Variability in Guinea  [PDF]
Tamba Nicolas Millimono, Sa?dou Moustapha Sall, Daouda Badiane, Alassane Bah, Moussa Diakhate, Ibra Toure, Mamadou Ba?lo Barry, Diakaria Diallo, Idrissa Diaby
Atmospheric and Climate Sciences (ACS) , 2017, DOI: 10.4236/acs.2017.74034
Abstract: Guinea is confronted to the increasing risks of bushfires that destroy thousands of hectares of vegetation cover every year. Very little research is devoted to the variability of those fires, which makes it a serious threat to both wildlife and human habitats. The current study investigates the spatial and temporal distribution of bushfires in the period from 2003 to 2016. The method used is the geospatial technology: we first filter pixels corresponding with active light supplied by MODIS images (Moderate Resolution Imaging Spectroradiometer) and estimate their densities following the square meshing procedure. Burned areas are deducted from the estimated pixel densities by calculations. The results highlight great occurrence of fires: 4 to 48 pixels of active fire per year and per 100 km2 depending on the location; 2 to 5 million hectares per year of burned areas (20,000 to 50,000 sqkm). Almost 8 to 24% the size of the whole country. The prefectures of Beyla, Siguiri, Kouroussa, Kankan, Dinguiraye, Mali and Tougué are the most exposed areas. Every year, fire activities are observed as from October and between May and June. They are however mitigated according to the regions (or the geographical domains). Summits of bushfires activities are generally reached between December and January.
Comparative Study of the West African Continental, Coastal, and Marine Atmospheric Profiles during the Summer of 2006
Ibrahima Kalil Kante,Daouda Badiane,Sa dou Moustapha Sall,Abdoulaye Deme,Arona Diedhiou
International Journal of Geophysics , 2012, DOI: 10.1155/2012/603949
Abstract: We used sounding data of the Multidisciplinary Analysis of the African Monsoon experience in summer 2006 at continental and coastal sites of West Africa, respectively, to analyze the vertical profiles of relative humidity, temperature, dew point, and speed and wind direction for the JJAS rainy period. The vertical gradient method is applied to the profiles of some thermodynamic parameters estimated from sounding data to do a comparative study of the structure and thermal properties, moisture, and static stability of the atmospheric boundary layer of inland, coastal, and marine sites to show consistent differences related to geographic factors. In vertical profiles of relative humidity, the intensity is higher in Dakar than in Niamey particularly in the core of the season. There are dry intrusions in the low levels at the beginning and end of the season in Dakar, which do not exist in Niamey. The mixing layer on the continent during the day can reach a height greater than 1100 m, and the inversion layer height can exceed 1700 m. Therefore, the maximum thickness of the boundary layer is observed on the continent during the day, while at night the marine boundary layer is the thickest. The diurnal evolution shows that the mixing layer thickness decreases during the night over the continent but increases at the coast and at sea. In the night at the continental site there is a division of the mixing layer with a consistent residual mixing layer. Continental boundary layer is more unstable during the day, while at night it is the marine boundary layer that is more unstable than the coastal and inland ones.
Comparative Study of the West African Continental, Coastal, and Marine Atmospheric Profiles during the Summer of 2006
Ibrahima Kalil Kante,Daouda Badiane,Sa?dou Moustapha Sall,Abdoulaye Deme,Arona Diedhiou
International Journal of Geophysics , 2012, DOI: 10.1155/2012/603949
Abstract: We used sounding data of the Multidisciplinary Analysis of the African Monsoon experience in summer 2006 at continental and coastal sites of West Africa, respectively, to analyze the vertical profiles of relative humidity, temperature, dew point, and speed and wind direction for the JJAS rainy period. The vertical gradient method is applied to the profiles of some thermodynamic parameters estimated from sounding data to do a comparative study of the structure and thermal properties, moisture, and static stability of the atmospheric boundary layer of inland, coastal, and marine sites to show consistent differences related to geographic factors. In vertical profiles of relative humidity, the intensity is higher in Dakar than in Niamey particularly in the core of the season. There are dry intrusions in the low levels at the beginning and end of the season in Dakar, which do not exist in Niamey. The mixing layer on the continent during the day can reach a height greater than 1100?m, and the inversion layer height can exceed 1700?m. Therefore, the maximum thickness of the boundary layer is observed on the continent during the day, while at night the marine boundary layer is the thickest. The diurnal evolution shows that the mixing layer thickness decreases during the night over the continent but increases at the coast and at sea. In the night at the continental site there is a division of the mixing layer with a consistent residual mixing layer. Continental boundary layer is more unstable during the day, while at night it is the marine boundary layer that is more unstable than the coastal and inland ones. 1. Introduction The term boundary layer was first introduced in the literature by Prandtl and Lustig [1]. Since then, many authors such as Turner [2], Monin [3], Zeman [4] and more, recently, Cushman-Roisin and Beckers [5] have studied the detailed description. The atmospheric boundary layer (ABL) has been variously defined, but it is commonly recognized as the lower part of the atmosphere, which is strongly influenced by the presence of the earth’s surface and responds to surface forcing with a timescale of about one hour or less. The ABL is the place where many processes, such as turbulence, friction, dispersion, energy dissipation, and wind shear occur. These processes are poorly parameterized in atmospheric models. Several ABL studies have focused on the turbulence but also on the mixing process triggered by significant warming or cooling [6]. Within the ABL, the transport of various quantities (heat, pollution, moisture, momentum, etc.) is mainly
Effects of different inputs of organic matter on the response of plant production to a soil water stress in Sahelian region  [PDF]
Abdoulaye Badiane, Ndeye Yacine Badiane Ndour, Fatou Guèye, Saliou Faye, Ibrahima Ndoye, Dominique Masse
Natural Science (NS) , 2012, DOI: 10.4236/ns.2012.412125
Abstract: The aim was to study the effects of organic management like the application of organic matters on crop production. This research is placed in the context of climate change impact mitigation. A field experiment was conducted during the dry season. Rainfall inputs were simulated by irrigation to study the effects of water stress during the flowering period of a grain on the agronomic and the physiological behavior of the plant. The measurements were made on the volumetric soil moisture, stomatal conductance, and leaf area index (LAI), grain yield, straw and weight of 100 grains. The water use efficiency (WUE) and yield losses were evaluated. The results of the volumetric soil moisture showed that the use of localized input under water stress (STR-T1) recorded the lowest moisture in the surface horizons. Treatment with localized input under water stress with or without fertilization (STR-T1, STR-T1 + N) showed an ability of stomatal regulation compared to the control (STR- T0) and the input application by spreading (STR- T2). (STR-T1 + N) has initiated an early stomatal closure of the plant because of the effect of nitrogen. However, despite a more pronounced water stress with stomatal closure, the LAI and the grain yield were greater with (STR-T1) and (STR-T1 + N). The results showed that the inputs of localized organic fertilization with or without nitrogen grain yields were the highest regardless of the hydric regime applied. However the losses of grain yield were higher in treatments with organic inputs in spreading and localized under water stress. The WUE by the crop was reduced compared to the control with organic inputs under STR. In this study we show that the use of organic matter increases de farmers risk and this notion of risk is high and it is necessary to consider this risk in the proposals of technical innovations.
Effect of the Continuum Removal in Predicting Soil Organic Carbon with Near Infrared Spectroscopy (NIRS) in the Senegal Sahelian Soils  [PDF]
Macoumba Loum, Mateugue Diack, Ndeye Yacine Badiane Ndour, Dominique Masse
Open Journal of Soil Science (OJSS) , 2016, DOI: 10.4236/ojss.2016.69014
Abstract: Spectroscopy plays a major role in the access of the analytical parameters of the soil. It tends to substitute the conventional laboratory analysis because hyperspectral data were least expensive and easier to obtain. The objective of this study was to evaluate the effect of the continuum removal (CR) in the validation of the accurate prediction model of the soil properties with Vis-NIR spectroscopy data. Few studies using Vis-NIR reflectance spectroscopy have well focused the calculation of the CR method; its effect in the calibration of the accurate models was also not well emphasized. In this study, we used the remote sensing software ENVI 4.7 to compute the CR function where the value of the continuum for each sample and for each spectral wavelength was obtained by dividing the reflectance values of the full spectrum (FS) with those of the continuum curve (CC). The partial least square regression (PLSR) model was applied in the spectral data from the soil of the Senegal Sahelian region. It was calibrated with both data from the full spectrum (FS) and those obtained after the application of the continuum removal. With the application of the CR, ultraviolet wavelengths (350 - 429 nm) and those of near infrared (2491 - 2500 nm) were removed from the explanatory variables of PLSR model. With the FS, all wavelengths between 350 and 2500 nm were taken into account in predicting soil properties. Our findings show a positive effect of the application of CR in the estimation of soil organic carbon. In calibration, the R2 increased up to 10% with the continuum removal in the model of 12 components (CP). In terms of validation, it’s the 15-component model which is the most accurate with the same range in calibration between the FS and the CR. The lowest RMSE ranged from 0.04 with the FS to 0.03 with the application of the CR in calibration and validation. These results show that the interest of this study as soil organic carbon is recognized as a key indicator of fertility of the soil in Sahelian-African regions. For future studies, it’s important to apply the model of neural networks to better evaluate the effect of continuum removal in predicting soil properties from the spectral data and other methods of preprocessing like the multiplicative scatter correction (msc).
Effects of the 2008 Financial Crisis on the Determinants of Foreign Direct Investments in the West African Economic and Monetary Union (WAEMU): A Panel Data Approach  [PDF]
Tibi Didier Zoungrana, Daouda Lawa tanToé
Modern Economy (ME) , 2018, DOI: 10.4236/me.2018.911109
Abstract: This article analyzes through a panel data analysis covering the period 1994 to 2016, the effects of the 2008 financial crisis on the determinants of Foreign Direct Investment in the West African Economic and Monetary Union (WAEMU). From the analysis, it turns out that this crisis has strongly impacted FDI’s determinants in the union. In fact, as consequence, it created a much more infatuation of resource-seeking investors in spite of market-seeking investors. This result shows that those countries can still attract investors even in time of crisis if they have tremendous natural resources, which makes the protection of these resources very important. In addition, we can notice that after the crisis, the stability in the region became an important decisional variable for foreign investors. That points out the importance of promoting a good political governance. Furthermore, the study has also shown that the financial crisis has been a stepping corner for the emergence of a third type of investors in the region (efficiency seeking investors).
Minimally Invaded Sentinel Lymph Node Model for the Development of Intraoperative Infrared Fluorescence Imaging  [PDF]
Badiane Serigne Moussa, Raes Florian, Julien Sobilo, Natkunarajah Sharuja, Lerondel Stéphanie, Le Pape Alain
Advances in Molecular Imaging (AMI) , 2018, DOI: 10.4236/ami.2018.84005
Abstract: In this study we implemented an axillary SLN invasion model to develop highly sensitive imaging strategies enabling detection of a very small amount of tumor cells. A highly diffusible molecular probe targeting αvβ3 and αvβ5 integrins was investigated either via IV or locoregional injections. We additionally documented the potential interferences of this Near Infrared Fluorescence Probe with Blue Patente V and ICG dyes routinely used to facilitate lymph node detection during surgery. The human mammary adenocarcinoma MDA-MB-231-luc model was injected into the forepaw of nude female rats to obtain a controlled invasion of the axillary LN. Thanks to its high sensitivity, BLI was selected to achieve in vivo quantitation of tumor cells in SLNs and determine eligible animals for the study. NIRF of integrins was performed at 680 nm both in vivo and ex vivo using spectral unmixing to suppress auto-fluorescence signal and preserve sensitivity. In vivo BLI was quite reliable in estimating discrete invasion by cancer cells in the LN with thresholds of detection and quantitation of about 500 and 1500 cells respectively. For fluorescence at 680 nm, in vivo imaging is not suitable to detect micro-invasion, but ex vivo fluorescence with spectral unmixing of SLNs confirmed the presence of a tumor burden as low as 1500 cells expressing αvβ3/αvβ5 integrins. Targeting few tumor cells inside a micro-invaded sentinel lymph node by molecular probes is not sensitive enough to provide direct in vivo or peroperative imaging. At the time NIRF is performed on the excised specimen, high sensitivity imaging associated with spectral unmixing allowed such detection within less than 1 minute of examination.
Photoionization Study of Cl II, Ar II and Kr II Ions Using the Modified Atomic Orbital Theory  [PDF]
Abdourahmane Diallo, Mamadou Diouldé Ba, Jean Kouhissoré Badiane, Momar Talla Gning, Malick Sow, Ibrahima Sakho
Journal of Modern Physics (JMP) , 2018, DOI: 10.4236/jmp.2018.914162
Abstract: Resonance energies of the Cl II-[3s23p3(2D5/2)]nd and [3s23p3(2P3/2)]nd, Ar II-3s23p4(1D2)ns, nd and of the Kr II [4s24p4(1D2)]ns, nd and 4s24p4(3P2,3P1)]ns, 4s24p4(3D2)]ns, nd and 4s24p4(3D2, 1S0)]ns, nd Rydberg series are reported. Natural widths of the Ar II-[3s23p4(1D2)]ns, nd series are also reported. Calculations are done in the framework of the Modified Atomic Orbital Theory (MAOT). Excellent agreements are obtained with available theoretical and experimental data. High lying accurate resonance energies up to n = 40 are tabulated. The possibility to use the MAOT formalism report rapidly with an excellent accuracy the position of the excitation resonances as well as their width within simple analytical formulae is demonstrated.
Study of the Sediments of the Dam of Okpara (Benin): Physico-Chemical Characterization and Speciation of Iron and Manganese  [PDF]
Fidele Suanon, Biaou Dimon, Daouda Mama, A.Lyde Tominti
Journal of Water Resource and Protection (JWARP) , 2013, DOI: 10.4236/jwarp.2013.57071
Abstract:

Iron and Manganese contents and parameters including pH, conductivity, and organic matter contents were determined in the sediments of the Okpara dam in Northern Benin. Fifteen samples were collected during a one-month period and analysed in laboratory using the method of sequential extraction of Tessier. The analyses indicated that sediments contained high concentrations in reducible fraction of Iron and relatively high contents of exchangeable fraction, acidhydrolysable fraction and residual fraction of Manganese. The findings of this study confirmed the hypotheses that the meal contents of the sediments were relatively high and varied according to the geochemical phases.

A Review and Update of Analytical and Numerical Solutions of the Terzaghi One-Dimensional Consolidation Equation  [PDF]
Cheikhou Ndiaye, Meissa Fall, Mapathe Ndiaye, Daouda Sangare, Abib Tall
Open Journal of Civil Engineering (OJCE) , 2014, DOI: 10.4236/ojce.2014.43023
Abstract: Practical resolution of consolidation problems that we often face requires an extensive and solid knowledge of the different parameters highlighted by the Terzaghi one-dimensional consolidation theory. This theory, with its assumptions, leads to a partial differential equation of second order in space and first order in time of pore water pressure. Analytical and numerical resolutions of this equation allow determining the water pressure variation before and after the application of a charge. Numerical modeling has enabled the simulation of the whole results obtained by the two methods of resolution (pressure, degree of consolidation, time factor, among others) to have a physical analysis and a lawful observation that lead to a suitable understanding of the phenomenon of Terzaghi one-dimensional consolidation.
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