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Modified atomic orbital theory applied to the calculation of high-lying 2(K,t)n±1,3P°rydberg series of he-like ions

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Natural Science 2012年第1期4卷 73-78页

作者： ibrahima Sakho 不详

the 2(1,0)n-1P°, 2(1,0)n +3P°, 2(0,1)n+1P°, and 2(0,1)n-3P° intershell Rydberg series of the helium-like ions are investigated in the framework of the modified Atomic Orbital theory (MAOt). High-lying energy resonances of He and excitation energy of the he- lium-like Li+ up to n = 10 are tabulated. In addition, total energy positions for low-lying states (n1,3P° autoionizing states of two-electron systems.

关键词： Atomic Orbital theory Screening constant Semi-empirical calculations autoionizing states Rydberg series helium-like ions

Valuation of Laterite in Low-cost Building in West Africa

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Journal of Architectural Environment & Structural Engineering Research 2020年第3期3卷 1-3页

作者： ibrahima Sow ibrahima Khalil Cisse Souleymane Mbingue Doctoral School of the University of thies(ed2ds) Senegal&Comapagnie Sahélienne d’EntreprisesDakarSenegal Laboratoire de Matériaux Mécanique et Hydraulique(LMMH)Ecole Polytechnique de thièsThièsSénégal Doctoral School of the University of thies(ed2ds) Senegal

the study of the performance of raw clay bricks has made it possible to develop laterite in Eco village construction *** tests(particle size analysis,Atterberg limits,Proctor,shrinkage limit,and sand equivalent)made it possible to characterize the laterite,the sand,and the E1 mixture(70%laterite and 30%sand).By adding binders to E1,three other types of mixtures E2,E3,and E4 have been *** improved E1 sample:(1)At 2.5%of cement gives E2;(2)At 10%of lime gives E3;(3)with 0.8%*** making the bricks using the samples E1,E2,E3,and E4,we perform uniform compression test at 3,7,and 21 *** samples have simple compressive strengths greater than 0.5 MPa(in accordance with standard NF EN 771-1)after 3 *** evolution from 0.5 to 2.5 MPa,between 3 and 7 days,shows a jump of *** 7 to 21 days the evolution curve of the Rc shows a slight ascension then a plateau pace(2.5,2.51,2.56 MPa).From these results,we concluded that they were used according to the area and the type of *** use of the sample E1 is proposed in arid zones or with low rainfall,the sample E2,and E3 in the rainy zones without risk of capillary rise and the sample E4 in the rainy zones with the risk of capillary rise.

关键词： Brick Cement Lime Lignosulfonates Simple compression Eco village

Controllability Approach for a Fluid Structure Interaction Problem

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Applied Mathematics 2012年第3期3卷 213-216页

作者： ibrahima Mbaye Department of Mathematics University of Thies Thies Senegal

the present paper presents a new method to solve fluid structure interaction problem. Our computational method is based on controllability approach. Given a target structural displacement we will find a control steering the displacement of the structure u to . We need to define a payoff functional (J): where u solves the structure equation for the control and is a fixed value. Our aim is to find a control which minimizes the payoff criterion. And therefore we find u the beam displacement, v the velocity of the fluid and p the pressure of the fluid.

关键词： Fluid Structure Interaction Finite Elements Method Controllability BFGS Method

Effects of different inputs of organic matter on the response of plant production to a soil water stress in Sahelian region

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Natural Science 2012年第12期4卷 969-975页

作者： Abdoulaye Badiane Ndeye Yacine Badiane Ndour Fatou guèye Saliou Faye ibrahima Ndoye Dominique Masse Research Center IRD-ISRA-UCAD of Bel-Air Laboratory of Soil Microbial Ecology and tropical Agrosystems Dakar Senegal Research Centre IRD-ISRA Bel-Air National Laboratory for Research on Crop Production Dakar Senegal University Cheikh Anta Diop Department of Plant Biology Dakar Senegal

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.

关键词： Organic Matter Water Stress Volumetric Soil Moisture Stomatal Conductance Leaf Area Index

Sedimentary characteristics and implications for hydrocarbon exploration in a retrograding shallow-water delta:An example from the fourth member of the Cretaceous Quantou Formation in the Sanzhao depression,Songliao Basin,NE China

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Petroleum Science 2022年第3期19卷 929-948页

作者： Quan-Sheng Cai Ming-Yi Hu Yi-Ni Liu Oumar-ibrahima Kane Qing-Jie Deng Zhong-gui Hu Hua Li Ngong-Roger Ngia School of Geosciences Yangtze UniversityWuhanHubei 430100China Key Laboratory of Exploration technologies for Oil and Gas Resources Ministry of EducationYangtze UniversityWuhanHubei 430100China Department of Geology University of BueaP.O.Box.63BueaCameroon

Based on the analysis of core,logging,and testing data,the fourth member of the Cretaceous Quantou Formation(K_(2)q^(4))in the Sanzhao depression,Songliao Basin,is investigated in order to understand the sedimentary characteristics and hydrocarbon exploration significance of a retrograding shallow-water *** results show that during the sedimentary period of K_(2)q^(4),the Sanzhao depression with a gentle basement experienced stable tectonic subsidence and suffered a long-term lake level rise caused by paleoclimate changes(from semiarid to semihumid),the K_(2)q^(4)in the study area were dominated by a fining-upward deltaic succession and had relatively stable *** the bottom to the top,the color of mudstone gradually changes from purplish-red to gray and grayish-green,the contents of caliche nodules decrease gradually,while the presence of pyrite in sediments becomes *** sandstones mainly composed of siltstone and fine sandstone with developed high-energy sedimentary structures constitute the main sand bodies of deltaic deposits,but the scale of channel sandstones decrease *** the long-term lake level rise and fining-upward sedimentary succession,purplish-red mudstone,caliche nodules and thin channel sandstones are still broadly distributed in the study area,and thin channel sandstones can be found at the top of K_(2)q^(4)covered by the black oil shale of Qingshankou *** assertations suggest that the study area was dominated by retrograding shallow-water delta deposits during the sedimentary period of K_(2)q^(4).In comparison with modern Poyang Lake,we infer that during the sedimentary period of K_(2)q^(4),the study area experienced frequent lake level fluctuations triggered by paleoclimate changes despite the long-term lake level rise,and the lake level fluctuations control the deposition of retrograding shallow-water *** addition,most of the thin channel sandstones distributed at the top of K_(2)q^(4)and cove

关键词： Depositional environment Retrograding shallow-water delta Lake level fluctuation Channel sandstone Hydrocarbon exploration K_(2)q^(4) Songliao Basin

Lightweight Key Management Scheme Using Fuzzy Extractor for Wireless Mobile Sensor Network

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Computers, Materials & Continua 2022年第4期71卷 1695-1712页

作者： Eid Rehman ibrahima Kalil toure Kashif Sultan Muhammad Asif Muhammad Habib Najam Ul Hasan Oh-Young Song Aaqif Afzaal Abbasi Department of Software Engineering Foundation UniversityIslamabad44000Pakistan Centre Informatique Universite Gamal Abdel Nasser deConakryGuinea Department of Software Engineering Bahria University Islamabad CampusIslamabadPakistan GDC Ahmad Karak Higher Education DepartmentKhyber PakhtunkhwaPakistan Department of Electrical and Computer Engineering Dhofar UniversitySalalahOman Department of Software Sejong UniversitySeoul05006Korea

the mature design of wireless mobile sensor network makes it to be used in vast verities of applications including from home used to the security *** such types of applications based on wireless mobile sensor network are generally using real time data,most of them are interested in real time communication directly from cluster head of cluster instead of a base station in cluster *** would be possible if an external user allows to directly access real time data from the cluster head in cluster wireless mobile sensor network instead of accessing data from base *** this leads to a serious security breach and degrades the performance of any security protocol available in this *** existing schemes for authentication and cluster key management for external users,exchange a number of messages between cluster head and base station to allow external to access real time data from the base station instead of cluster *** increase communication cost and delay in such real time access *** handle this critical issue in cluster wireless mobile sensor network,we propose a lightweight authentication and key management scheme using a fuzzy *** this scheme,any external user can access data directly from the cluster head of any cluster without the involvement of the base *** proposed scheme only uses the one-way hash functions and bitwise XOR operations,apart from the fuzzy extractor method for the user biometric verification at the login *** presented scheme supports scalability for an increasing number of nodes using *** proposed scheme increases the life-time of the network by decreasing the key pool size.

关键词： Fuzzy extractor user authentication key management cluster session key wireless mobile sensor network

Coronavirus Disease 2019 (COVID-19) in Conakry, Republic of guinea: Analysis and Relationship with Meteorological Factors

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Atmospheric and Climate Sciences 2021年第2期11卷 302-323页

作者： ibrahima Kalil Kante ibrahima Diouf tamba Nicolas Millimono Jean Moussa Kourouma Laboratoire de Physique de l’Atmosphère et de l’Océan Siméon Fongang école Supérieure Polytechnique Université Cheikh Anta Diop Dakar Dakar Senegal Direction Nationale de la Météorologie de guinée Conakry Guinea Université Gamal Abdel Nasser de Conakry/Laboratoire d’Enseignement et de Recherche en énergétique Appliquée de Conakry Conakry Guinea NOAA Center for Weather and Climate Prediction College Park Maryland USA Institut Supérieur des Sciences de l’Education de guinée (ISSEG) Conakry Guinea Department of Plant and Environmental Science School of Natural Resource Copperbelt University Kitwe Zambia

the coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), dates back to December 29, 2019, in Wuhan, China. It quickly spreads like wildfire to all continents in the following months. In guinea, the first case of COVID-19 and death were all reported respectively on March 12 and April 16, 2020. Since then, several studies have found a relationship between certain environmental conditions such as the meteorological factors to have the potential of contributing to the spread of the virus. thus, this study aims at examining the extent to which observed meteorological factors might have contributed to the spread of the coronavirus disease 2019 (COVID-19) cases in Conakry, from March 1 to May 31, 2020. Meteorological factors such as temperature (tmin, Tmean and Tmax) and relative humidity (RHmin, RHmean and RHmaxtyle="font-family:Verdana;">) were analyzed together with the data on the COVID-19. the dynamic of the COVID-19 in guinea was analyzed along with that of some west African countries. the analysis on the dynamic of the COVID-19 pandemic in West Africa indicated guinea as one of the most affected countries by the pandemic after Nigeria and Ghana. the study found that in general an increase in the temperature is linked to a decline in the COVID-19 number of cases and deaths, while an increase in the humidity is positively correlated to the number of cases and deaths. Nevertheless,

关键词： Conakry guinea COVID-19 Meteorological Factors temperature Humidity

Microfacies and Depositional Environments of Miocene Isolated Carbonate Platforms from Central Luconia, Offshore Sarawak, Malaysia

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Acta Geologica Sinica(English Edition) 2017年第5期91卷 1778-1796页

作者： Hammad tariq JANJUHAH José Antonio GáMEZ VINtANED Ahmed Mohamed Ahmed SALIM ibrahima FAYE Mumtaz Muhammad SHAH Deva Prasad GHOSH SEACARL Department of Geoscience University Technology PETRONAS Perak Malaysia 32610 Department of Geoscience University Technology PETRONAS Perak Malaysia 32610 Department of Fundamental and Applied Science University Technology PETRONAS Perak Malaysia 32610 Department of Earth Science Quaid-i-Azam UniversityIslamabad Pakistan 45320 CoE in CSIf Department of Geoscience University Technology PETRONAS Perak Malaysia 32610

the Luconia Province-offshore Sarawak-is a key geological unit for understanding the distribution of hydrocarbon resources in Malaysia. Nevertheless, little effort has been made to address the palaeoenvironmental characteristics of the tertiary carbonates in the key sector of Central *** study the sedimentology and petrography of core samples from a well in Central Luconia, for which thirteen microfacies have been identified reflecting different depositional settings. this is the first microfacies scheme elaborated for Luconian carbonates. Lithofacies and microfacies distribution are compatible with deposition in a reef complex, originating around a framework reef, within the euphotic zone. Sediments were deposited in environments of backreef, reef crest, and forereef. the fair weather wave base is marked by the presence of coralline red algae, foraminifera, decreasing degree of bioclast fragmentation and other microfacies features. As a result, a depositional-environmental model is constructed, depicting a reef complex built around a framework reef developed on the margin of an isolated platform. In addition, an innovative, preliminary time series analysis of facies, microfacies and depositional environment data reveal the existence of seasonal cycles in the stacking patterns of facies and microfacies.

关键词： central Luconia sedimentology microfacies reef complex depositional environments time series

Conjugate Gradient Method to Solve Fluid Structure Interaction Problem

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Applied Mathematics 2017年第4期8卷 444-452页

作者： Mamadou Diop ibrahima Mbaye thies University Thies Senegal Department of Mathematics and Computer Science Thies University Thies Senegal

In this paper, we propose a method to solve coupled problem. Our computational method is mainly based on conjugate gradient algorithm. We use finite difference method for the structure and finite element method for th... 详细信息

关键词： Fluid-Structure Interaction Beam Stokes Finite Element Finite Difference Method Conjugate Gradient Method