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Advances in Entomology 2016年第1期4卷 19-24页

作者： Franceline Doh Koffi Yoboue Blanchard Eric Zadjehi Koffi Auguste Emmanuel Issali Kouassi Allou mamadou dagnogo Station de Recherche sur le Cocotier Port-Bou&euml t Marc Delorme CNRA Abidjan C&ocirc te d’Ivoire UFR Science de la Nature Université Nangui Abrogoua Abidjan C&ocirc te d’Ivoire UFR Science de la Nature Université Nangui Abrogoua Abidjan C?te d’Ivoire

Pseudotheraptus devastans Distant (Heteroptera: Coreidae), is an important coconut pest in C?te d’Ivoire. The stings from Nymph and adult cause not only the falling of immature nuts, but also their deformation. This triggers losses of production in the order can reach 80%. Little information is available about this pest. Those existing are limited to its ecology and damages caused in host-plants. The present investigation is aimed to study the life cycle of this pest. The experiment was carried out in a coconut field of the Marc Delorme Coconut Research Station (MDCRS). On these coconut palms, bunches between 3 and 4 months of age, enclosed in cage were used. Development duration from an egg to adult emergence averaged 28.26 days. The average incubation period was on average 6.63 days and fertility rate of eggs was 98.01%. Nymphal development period was 21.63 days. The sex-ratio is in favour of females which live 112.6 ± 13.45 days. These females laid on average 198.85 ± 36.05 eggs. The males lived on average 131.3 ± 17.7 days. The knowledge of these different parameters could allow the development of a control method based on the breaking of life cycle of this pest.

关键词： Coreid Life Cycle Rearing Nymph Coconut Pest

Chemically induced changes in the geotechnical response of cementing paste backfill in shaking table test

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第3期13卷 513-528页

作者： Imad Alainachi mamadou Fall Department of Civil Engineering University of OttawaOttawaOntarioK1N 6N5Canada

Cemented paste backfill(CPB)is extensively used for underground mine support and/or tailings ***,CPB behavior under cyclic loadings might be affected by the chemistry of its porewater,which often contains sulphate *** today,no studies have addressed the effect of sulphate on the response of CPB to cyclic loadings by using shaking table *** study presents new findings of assessing the effect of the sulphate in the pore water of CPB on its geotechnical response to cyclic loading by using shaking *** mixtures were prepared(with and without sulphate),poured into a flexible laminar shear box,cured to 4 h,and then exposed to cyclic loading using one-dimensional(1D)shaking *** parameters(*** water pressure,settlement,lateral deformation,acceleration,electrical conductivity,effective stress,and liquefaction susceptibility)were monitored or determined before,during,and after *** results indicate that the sulphate-bearing CPB cured to 4 h can be prone to liquefaction under the studied ***,sulphate-free CPB samples are resistant to *** results are expected to contribute to a better understanding of the effect of water chemistry on the cyclic behavior of CPB,consequently enhancing the cost-effective design of CPB structures.

关键词： Cemented paste backfill(CPB) Liquefaction Shaking table Tailings Mine Sulphate

Strength evolution and deformation behaviour of cemented paste backfill at early ages： Effect of curing stress, filling strategy and drainage

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International Journal of Mining Science and Technology 2016年第5期26卷 809-817页

作者： Ghirian Alireza Fall mamadou Department of Civil Engineering University of Ottawa 161 Louis Pasteur Ottawa K1N 6N5 ON Canada

In this study, a pressure cell apparatus is developed to investigate the early age evolution of the strength and deformation behaviour of cemented paste backfill(CPB) when subjected to various loading conditions under different curing scenarios. The different curing scenarios that are simulated include:(1)drained and undrained conditions,(2) different filling rates,(3) different filling sequences, and(4) different curing stresses. The findings show that drainage, curing stress, curing time and filling rate influence the mechanical and deformation behaviours of CPB materials. The coupled effects of consolidation, drainage and suction contribute to the strength development of drained CPB subjected to curing stress. On the other hand, particle rearrangement caused by the applied pressure and suction development due to self-desiccation plays a significant role in the strength gain of undrained CPB cured under ***, curing stress induces slightly faster rate of cement hydration, which can contribute to strength acquisition.

关键词： Cemented paste backfill Tailings Pore pressure Curing under stress Plug fill Cement

A column study of the hydro-mechanical behavior of mature fine tailings under atmospheric drying

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International Journal of Mining Science and Technology 2017年第2期27卷 203-209页

作者： Anis Roshani mamadou Fall Kevin Kennedy Department of Civil Engineering University of OttawaOttawa KIN 6N5Canada

In this paper, the hydro-mechanical behavior and physical properties of mature fine tailings(MFT) under atmospheric drying are investigated through a column study. In the study, evaporation takes place in the development of suction in the upper parts of the column and increasing suction leads to higher strength in the tailings. After 5 days, the suction in the first lift is around 17 k Pa in the upper part of the *** a second lift is added, the first lift initially loses strength but over a 30 days' period, the strength is recovered to its prior value and suction in the second lift reaches 500 k Pa. The vane shear strength values show a substantial increase in the strength of the MFT after 30 days under atmospheric drying and drainage. The 90% strength found in the column exceeds the threshold(5 k Pa). The hydraulic-mechanical properties of the deposited tailings are closely coupled due to several mechanisms, such as evaporation,drainage, self-consolidation, suction and crack development. The findings of this study will provide a better understanding of the placement behavior of multiple lifts of MFT and thus contribute to reclamation design standards and reduce the use of dedicated disposal areas.

关键词： Tailings Oil sand Environment Drying Multi-lift deposition

Neutral stochastic delay partial functional integro-differential equations driven by a fractional Brownian motion

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Frontiers of Mathematics in China 2013年第4期8卷 745-760页

作者： Tomas CARABALLO mamadou Abdoul DIOP Dpto. Ecuaciones Diferenciales y Analisis Numerico Universidad de Sevilla Apdo. de Correos 1160 41080-Sevilla Spain Universite Gaston Berger de Saint-Louis UFR SAT Departement de Mathematiques 234 Saint-Louis Senegal

This paper deals with the existence and uniqueness of mild solutions to neutral stochastic delay functional integro-differential equations perturbed by a fractional Brownian motion BH, with Hurst parameter H E （1/2, 1）. We use the theory of resolvent operators developed by R. Grimmer to show the existence of mild solutions. An example is provided to illustrate the results of this work.

关键词： Resolvent operator C0-semigroup Wiener process mild solution fractional Brownian motion

Swelling ability and behaviour of bentonite-based materials for deep repository engineered barrier systems:Influence of physical,chemical and thermal factors

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第3期14卷 689-702页

作者： Mohammed Alzamel mamadou Fall Sada Haruna Department of Civil Engineering University of OttawaOttawaOntarioK1N 6N5Canada

Compacted bentonite-sand(B/S)mixtures have been used as a barrier material in engineered barrier systems(EBSs)of deep geological repositories(DGR)to store nuclear *** study investigates the individual and combined effects of different chemical compositions of deep groundwaters(chemical factor)at potential repository sites in Canada(the Trenton and Guelph regions in Ontario),heat generated in DGRs(thermal factor),dry densities and mass ratios of bentonite and sand mixtures(physical factors)on the swelling behavior and ability of bentonite-based *** this study,swelling tests are conducted on B/S mixtures with different B/S mix ratios(20/80 to 70/30),compacted at different dry densities(ρd=1.6-2 g/cm^(3)),saturated with different types of water(distilled water and simulated deep groundwater of Trenton and Guelph)and exposed to different temperatures(20℃-80℃).Moreover,scanning electron microscopy(SEM)analyses,mercury intrusion porosimetry(MIP)tests and X-ray diffractometry(XRD)analyses are carried out to evaluate the morphological,microstructural and mineralogical characteristics of the B/S *** test results indicate that the swelling potential of the B/S mixtures is significantly affected by these physical and chemical factors as well as the combined effects of the chemical and thermal factors.A significant decrease in the swelling capacity is observed when the B/S materials are exposed to the aforementioned groundwaters.A large decrease in the swelling capacity is observed for higher bentonite content in the ***,higher temperatures intensify the chemically-induced reduction of the swelling capacity of the B/S barrier *** decrease in the swelling capacity is caused by the chemical and/or microstructural changes of the *** results from this research will help engineers to design and build EBSs for DGRs with similar groundwater and thermal conditions.

关键词： Deep geological repository Engineered barrier Bentonite-sand materials Nuclear waste Swelling capacity Swelling strain

A multiphysics-viscoplastic cap model for simulating blast response of cemented tailings backfill

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第3期9卷 169-182页

作者： Gongda Lu mamadou Fall Liang Cui Civil Engineering Department University of Ottawa Ottawa ON Canada

Although a large number of previous researches have significantly contributed to the understanding of the quasi-static mechanical behavior of cemented tailings backfill,an evolutive porous medium used in underground mine cavities,very few efforts have been made to improve the knowledge on its response under sudden dynamic loading during the curing *** fact,there is a great need for such information given that cemented backfill structures are often subjected to blast loadings due to mine *** this study,a coupled thermo-hydro-mechanical-chemical(THMC)-viscoplastic cap model is developed to describe the behavior of cementing mine backfill material under blast loading.A THMC model for cemented backfill is adopted to evaluate its behavior and evolution of its properties in curing processes with coupled thermal,hydraulic,mechanical and chemical ***,the model is coupled to a Perzyna type of viscoplastic model with a modified smooth surface cap envelope and a variable bulk modulus,in order to reasonably capture the nonlinear and rate-dependent behaviors of the cemented tailings backfill under blast *** of the parameters required for the variable-modulus viscoplastic cap model were obtained by applying the THMC model to reproducing evolution of cemented paste backfill(CPB)properties in the curing ***,the behavior of hydrating cemented backfill under high-rate impacts can be evaluated under any curing time of *** validation results of the proposed model indicate a good agreement between the experimental and the simulated *** authors believe that the proposed model will contribute to a better understanding of the performance of hydrating cemented backfill under blasting,and also to practical risk management of backfill structures associated with such a dynamic condition.

关键词： Thermo-hydro-mechanical-chemical (THMC) coupling Multiphysics processes Tailings Paste backfill Cap model Blast

Geotechnical characterization of peat-based landfill cover materials

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Journal of Rock Mechanics and Geotechnical Engineering 2016年第5期8卷 596-604页

作者： Afshin Khoshand mamadou Fall Faculty of Engineering K.N.Toosi University of Technology Department of Civil Engineering University of Ottawa

Natural methane （CH4） oxidation that is carried out through the use of landfill covers （biocovers） is a promising method for reducing CH4 emissions from landfills. Previous studies on peat-based landfill covers have mainly focused on their biochemical properties （e.g. CH4 oxidation capacity）. However, the utilization of peat as a cover material also requires a solid understanding of its geotechnical properties （thermal, hydraulic, and mechanical）, which are critical to the performance of any biocover. Therefore, the objective of this context is to investigate and assess the geotechnical properties of peat-based cover materials （peat, peat–sand mixture）, including compaction, consolidation, and hydraulic and thermal conductivities. The studied materials show high compressibility to the increase of vertical stress, with compression index （Cc） values ranging from 0.16 to 0.358. The compressibility is a function of sand content such that the peat–sand mixture （1：3） has the lowest Cc value. Both the thermal and hydraulic conductivities are functions of moisture content, dry density, and sand content. The hydraulic conductivity varies from 1.74 × 10^-9 m/s to 7.35 × 10^-9 m/s, and increases with the increase in sand content. The thermal conductivity of the studied samples varies between 0.54 W/（m K） and 1.41 W/（m K） and it increases with the increases in moisture and sand contents. Increases in sand content generally increase the mechanical behavior of peat-based covers; however, they also cause relatively high hydraulic and thermal conductivities which are not favored properties for biocovers.

关键词： Landfill Geotechnical engineering Landfill cover Peat Compaction Compressibility Hydraulic and thermal conductivity

Enhancing the reusability and interoperability of artificial neural networks with DEVS modeling and simulation

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International Journal of Modeling, Simulation, and Scientific Computing 2016年第2期7卷 88-108页

作者： David Ifeoluwa Adelani mamadou Kaba Traore Department of Computer Science African University of Science and Technology AbujaNigeria LIMOS CNRS UMR 6158 Universit´e Blaise PascalClermont-Ferrand 2 Campus des Cezeaux63173 Aubiere

Artificial neural networks(ANNs),a branch of artificial intelligence,has become a very interesting domain since the eighties when back-propagation(BP)learning algorithm for multilayer feed-forward architecture was introduced to solve nonlinear *** is used extensively to solve complex nonalgorithmic problems such as prediction,pattern recognition and ***,in the context of a holistic study,there may be a need to integrate ANN with other models developed in various paradigms to solve a *** this paper,we suggest discrete event system specification(DEVS)be used as a model of computation(MoC)to make ANN models interoperable with other models(since all discrete event models can be expressed in DEVS,and continuous models can be approximated by DEVS).By combining ANN and DEVS,we can model the complex configuration of ANNs and express its internal ***,we are extending the DEVS-based ANN proposed by Toma et al.[A new DEVS-based generic art-ficial neural network modeling approach,The 23rd European Modeling and Simulation Symp.(Simulation in Industry),Rome,Italy,2011]for comparing multiple configuration parameters and learning algorithms and also to do *** DEVS models are described using the high level language for system specification(HiLLS),[Ma¨ıga et al.,A new approach to modeling dynamic structure systems,The 29th European Modeling and Simulation Symp.(Simulation in Industry),Leicester,United Kingdom,2015]a graphical modeling language for *** developed platform is a tool to transform ANN models into DEVS computational models,making them more reusable and more interoperable in the context of larger multi-perspective modeling and simulation(MAS).

关键词： Artificial neural networks DEVS Z-schema reusability interoperability HiLLS learning algorithm modeling and simulation

Comment on review article:Chronic hepatitis C virus infection cascade of care in pediatric patients

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World Journal of Gastroenterology 2022年第14期28卷 1494-1498页

作者： Nouhoum Bouare mamadou Keita Jean Delwaide Biomedical Sciences National Institute of Public HealthBamako 1771Mali Department of Prevention Medical and Psychosocial ManagementCSLSHIV-TB-HBamako E 595Mali Department of Gastroenterology and Hepatology CHULiegeLiege 4000Belgium

An enhanced cascade of care should include a younger population,helping to achieve the goal of the World Health Organization with a focus on elimination in the pediatric ***,enhanced screening and awareness efforts and continued education of health care providers will improve the outcomes of chronic hepatitis C virus(HCV)infection in the pediatric *** present work discusses and comments on the topic"cascade of care in HCV chronic pediatric patients".

关键词： Cascade of care Hepatitis C virus Chronic patients Pediatric population Disease management Commentary