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Journal of Water Resource and Protection 2012年第11期4卷 944-953页

作者： William Assatsé Teikeu Philippe Nouck Njandjock dieudonné bisso Quentin Yene Atangana Jean-Paul Sep Nlomgan Department of Earth Science University of Yaounde I Yaounde Cameroon Department of Physics Faculty of Science University of Yaounde I Yaounde Cameroon National Institute for Geologic and Mining Research Yaounde Cameroon

Detailed local geological and hydrogeophysical investigations were carried out for the aquifer in Yaoundé, Cameroon to delineate the architecture of different subsurface geological horizons using lithologs and generated vertical electrical sounding (VES) data. An attempt has also been made to estimate aquifer transmissivity from resistivity data. The transmissivity of the uncon?ned aquifer was computed by determining the Dar-Zarrouk parameters (longitudinal unit conductance and transverse unit resistance) and were compared with the actual field transmissivity. The results showed a direct relation between aquifer transmissivity and transverse resistance. The relationship established has therefore, been generalized in the study area in order to evaluate hydraulic conductivity and transmissivity at all the points where geoelectrical measurements have been carried out. This generalization allows one to derive maps of the product Kσ and transmissivity in the study area based on geoelectrical measurements. These maps are important in future modelling processes oriented towards better exploitation of the aquifers.

关键词： Hydrogeophysical Transmissivity Hydraulic Conductivity Yaounde

Application of Coefficient of Anisotropy to the Geophysical Prospecting of Campo—Ma’an Area of the Ntem Complex in Cameroon

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Open Journal of Geology 2017年第12期7卷 1801-1818页

作者： Njingti-Nfor Owona Angue Marie Louise Kue Petou Rokis Malquaire bisso dieudonné Lando Tsakou Julyo Achille Postgraduate School of Sciences Technologies & Geosciences University of Yaoundé I Yaoundé Cameroon Department of Physics Advanced Teacher Training College University of Yaoundé I Yaoundé Cameroon National Institute of Cartography Yaoundé Cameroon School of Geosciences China University of Petroleum Qingdao China

Audiomagnetotelluric data were acquired for 10 sounding stations in open fields and roads along the main highways from Campo to Ma’an in Cameroon. An application of the coefficients of anisotropy was used to determine the tectonic settings and the nature of the contacts between the sedimentary formation of the Kribi-Campo basin and the cratonic Ntem Complex. The results of this study show that apart from the sedimentary formation, the metamorphic formation in this area comprises two metamorphic blocks: a regional metamorphic block which might be igneous or granitic in nature and composition and seem to be Precambrian and plutonic in origin and a contact or transitional metamorphic block, which might represent schist or gneiss rocks. The contact or transitional metamorphic block might be as a result of a long period of contact between regional metamorphic rocks and rocks of sedimentary formation. These contact/transitional metamorphic rocks which are found sandwiched between rocks of sedimentary formation and rocks of the regional metamorphic block and at varied depths confirm the existence of vertical and sub-vertical contacts between the Kribi-Campo basin and the cratonic Ntem complex. Two types of rock contacts have been identified: a sedimentary-schist contact which is found at the boundary between the sedimentary formation and the transitional metamorphic block and a schist-granite contact between the transitional and regional metamorphic blocks. Two main formations: a sedimentary formation, which is found in the Kribi-Campo sub-basin and the Ntem River bed and its flood plains and the metamorphic formation which includes both the transitional and regional metamorphic rocks have also been identified in the area of study. Subsurface rocks and rock materials have been observed to be highly resistive and occupying almost the entire subsurface in the area of study confirming the high vertical tectonic stability of the Ntem Complex even at contact with the sedimentar

关键词： Anisotropy Telluric Geo-Electric Subsidence Isotropic Vertical Faults Tectonics

Determination of the Structural Lineaments in the Kribi-Campo-Ma’an Area from a Multi-Scale Analysis of Gravity Data Using the HGM and Euler 3D Deconvolution Approaches

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International Journal of Geosciences 2016年第9期7卷 1122-1143页

作者： Owona Angue Marie Louise Clotilde Assembe Stephane Patrick Njingti Nfor Ngoh Jean Daniel Ndougsa Mbarga Theophile Kue Petou Rokis bisso dieudonné Department of Physics Advanced Teacher Training College University of Yaoundé I Yaoundé Cameroon Postgraduate School of Sciences Technologies & Geosciences University of Yaoundé I Yaoundé Cameroon Department of Physics Faculty of Science University of Bamenda Bambili Cameroon

With the aim to produce a detailed structural map and then enhance the geological information of the south-western Cameroon, a field gravity study is carried out in the Kribi-Campo-Ma’an area (SW Cameroon). This study area is assumed to undergo pending active tectonics as witnessed by several earthquakes [1]. Besides, the area has been affected by some shears that gave rise to many major faults including the Kribi-Campo Fault (KCF). This N-S lineament is an active fault corresponding to the NW margin of the CC [2] [3] and related to the development of the Kribi-Campo basin. The gravity data analysis enables to highlight many deeply-seated structural features trending in the NE, NNE, N-S, NNW, NW and E-W directions in this region. The NW-SE trend is more strongly developed than the other identified trends and could have deeply affected the major NNE structure. The NNE-SSW to N-S fractures and faults which are local relays of the Kribi-Campo fault are related to the Kribi shear zone. The fairly good clustering observed on local maxima of the horizontal gradient magnitude enables to suggest that the contacts outlined have vertical to subvertical dips. However, a probable interpretation of these features is that they are vertical to subvertical faults which follow the aforementioned directions. The location of the study area in the gulf of Guinea suggests that it sustains tectonics related both to the equatorial and the south Atlantic oceans opening.

关键词： Gravity Anomaly Lineament Kribi-Campo Fault Dip

Geophysical Contribution for the Determination of Aquifer Properties in Memve Ele, South Cameroon

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Journal of Water Resource and Protection 2012年第10期4卷 885-890页

作者： Harlin L. E. Nkoungou Philippe N. Nouck dieudonné bisso Stéphane Assembe Eliézer M. Dicoum Department of Earth Sciences Faculty of Science University of Yaounde I Yaounde Cameroon Department of Physics Faculty of Science University of Yaounde I Yaounde Cameroon

This article aims to localise aquifer and to estimate hydraulic parameters such as transmissivity and tranverse resistance in the Memve Ele dam site (26.35 km2) in South-Cameroon region, using audiomagnetotelluric (AMT) method. For this purpose, resistivity data are collected at twenty-two measurement stations distributed along two perpendicular profiles in the study area. The sounding curves of phase and impedance are modelled and interpreted. The geological models and geoelectrical sections are also provided. The transverse resistivity and transmissivity field maps are plotted. The audiomagnetotellurics insights have been compared with boreholes. All these results allow us to localise the area which may be suitable to set up monitoring wells.

关键词： Hydraulic Parameters Aquifer Audio-Magnetotelluric Method Sounding Curves Memve Ele

Mathematical Analysis and Simulation of an Age-Structured Model of Two-Patch for Tuberculosis (TB)

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Applied Mathematics 2016年第15期7卷 1882-1902页

作者： Badjo Kimba Abdoul Wahid Saley bisso Department of Mathematics and Computer Science Abdou Moumouni University Niamey Niger

This paper studied a structured model by age of tuberculosis. A population divided into two parts was considered for the study. Each subpopulation is submitted to a program of vaccination. It was allowed the migration of vaccinated people only between the two patches. After the determination of and , the local and global stability of the disease-free equilibrium was studied. It showed the existence of three endemic equilibrium points. The theoretical results were illustrated by a numeric simulation.

关键词： Age-Structured Reproductive Number Two-Patch TB Stability Simulation

Mathematical Analysis of an Optimal Control Problem of Surface Water Pollution

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Applied Mathematics 2017年第2期8卷 164-179页

作者： Djibo Moustapha Hamidou Haoua Saley bisso Department of Mathematics and Informatics Abdou Moumouni University Niamey Niger

We present in this paper a new technique based on Gelfand’s triplet [1] and include differential theory to make a theoretical analysis of an optimal control problem with constraints governed by coupled partial differential equations. This technique allowed us to give some theoretical results of existence and uniqueness of the solution of constraints and characterize the optimal control.

关键词： Sand Dune Formation Objective Function Operators State Equation

Psychopathological outcomes and defence mechanisms in clinically healed adults with a paediatric cancer history: an exploratory study

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General Psychiatry 2021年第4期34卷 60-68页

作者： Antonino Petralia Emanuele bisso Ilaria Concas Antonino Maglitto Nunzio Bucolo Salvatore Alaimo Andrea Di Cataldo Maria Salvina Signorelli Alfredo Pulvirenti Eugenio Aguglia Department of Clinical and Experimental Medicine Psychiatry UnitUniversity of CataniaSchool of MedicineCataniaItaly Department of Mathematics and Computer Science University of CataniaCataniaItaly Department of Clinical and Experimental Medicine Pediatric Hemato-Oncology UnitUniversity of CataniaSchool of MedicineCataniaItaly

Background The incidence of paediatric cancers has increased in recent years;however,with advances in the treatment of paediatric cancer,almost 80%of children and adolescents who receive a diagnosis of cancer become long-term *** the high stress levels associated with cancer,it becomes important to ascertain the risk and likelihood of psychiatric disorders in adult paediatric cancer *** This study aims to investigate the relationship between defence styles and predisposition to psychiatric diseases in adults with a history of paediatric *** We performed an explorative study on a sample of 66 clinically healed adults with a history of paediatric cancer(survivors)during follow-up visits at the University Hospital‘Policlinico G Rodolico’of Catania(Italy)and 98 healthy controls among medicine *** administered the Defence Mechanism Inventory(DMI)to assess defence *** Symptom Checklist-90-Revised(SCL-90-R)and the Davidson Trauma Scale(DTS)were administered to assess psychopathological *** conducted comprehensive statistical analysis based on correlation analysis and mediation analysis to investigate the relationship between defence styles and psychopathological outcomes in survivors compared with *** The survivors obtained statistically significant lower values in TAO,PRO and TAS defence styles and a higher value in *** groups showed non-pathlogical mean scores in DTS and SCL-90-R(with an exception of the obsessive-compulsive subscale),with lower mean values among *** results of mediation analysis showed that TAS had mediation effects on interpersonal sensitivity,anxiety,PSDI,GSI and avoidance,while TAO had mediation effects on DTS total score and ***,for these psychopathological indices,the effect of the oncological pathology was indirect and mediated by TAO or *** analysis exlcluded mediation effects between the remaining variables and defence *** Integrati

关键词： clinically pathological TAO

Numerical Modelling and Simulation of Sand Dune Formation in an Incompressible Out-Flow

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Applied Mathematics 2015年第5期6卷 864-876页

作者： Yahaya Mahamane Nouri[alassanenouri@yahoo.fr] Saley bisso Department of Mathematics and Informatic Abdou Moumouni Unversity Niamey Niger

In this paper, we are concerned with computation of a mathematical model of sand dune formation in a water of surface to incompressible out-flows in two space dimensions by using Chebyshev projection scheme. The mathematical model is formulate by coupling Navier-Stokes equations for the incompressible out-flows in 2D fluid domain and Prigozhin’s equation which describes the dynamic of sand dune in strong parameterized domain in such a way which is a subset of the fluid domain. In order to verify consistency of our approach, a relevant test problem is considered which will be compared with the numerical results given by our method.

关键词： Sand Dune Formation Navier-Stokes Equations Incompressible Out-Flows Chebyshev Projection Scheme

Study of the 1D Saint-Venant Equations and Application to the Simulation of a Flood Problem

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Journal of Applied Mathematics and Physics 2020年第7期8卷 1193-1206页

作者： Maman Yarodji Abdoul Kader Rabé Badé bisso Saley Department of Mathematics and Computer Science Faculty of Science and Technology Abdou Moumouni University Niamey Niger

In this paper we are concerned with the mathematical and numerical analysis of the one-dimensional Saint-Venant equations. Thus, we prove the existence of a weak solution for any fixed time and with low regularity on the data. For the numerical approach we use the Rusanov scheme to approximate the flux and the hydrostatic reconstruction method which consists of decentering the source term at the interface. A numerical test of the proposed resolution is performed on a non-uniform topography.

关键词： Shallow Water Equations Hyperbolic System Finite Volume Method Weak Solution

Contribution to the Mathematical Modeling of COVID-19 in Niger

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Applied Mathematics 2020年第6期11卷 427-435页

作者： Badjo Kimba Abdoul Wahid Djibo Moustapha Hassane Ganda Rabi Saley bisso Department of Exact and Applied Sciences Dosso Unversity Dosso Niger Department of Mathematics and Computer Sciences Abdou Moumouni Unversity Niamey Niger

We are interested in this paper in the modeling and analysis of the disease of COVID-19 applied to the capital of Niger: Niamey. The model we are presenting takes into account the strategy that the country has adopted to fight this pandemic. The spread of the infectious agent within the population is a dynamic phenomenon: the number of the healthy and sick individuals changes over time, depending on the contacts during which the pathogen passes from an infected individual to a healthy individual. We model this propagation phenomenon by a set of differential systems equations and determine its behavior through a numerical resolution.

关键词： Covid-19 Epidemiology Differential Equations Operators Numerical Analysis Matlab