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Reversible Semi-Fragile Watermarking Technique for Integrity Control of Relational Database

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Engineering（科研） 2024年第9期16卷 309-323页

作者： Ali Hamadou abdoul aziz Issaka Hassane Lanciné Camara Harouna Naroua Department of Mathematics Dan Dicko Dankoulodo University of Maradi Maradi Niger Social Science and Management University of Bamako Bamako Mali Department of Mathematics and Computer Science Abdou Moumouni University Niamey Niger

Reversible watermarking schemes for relational database are usually classified into two groups: robust schemes and fragile schemes. The main limitation of existing reversible fragile methods is that they cannot differentiate between legal and malicious modifications. In this paper, we introduce a novel lossless semi-fragile scheme based on prediction-error expansion for content protection of relational database. In the proposed method, all attributes in a database relation are first classified according to their sensitivity to legitimate updates. Then, the watermark is embedded by expanding the prediction error of the two least significant digits of securely selected attributes. At watermark extraction, the proposed method has the ability to fully restore the original data while detecting and localizing tampering. The applicability of our method is demonstrated theoretically and experimentally.

关键词： Semi-Fragile Watermarking Integrity Control Reversibility Prediction-Error Expansion

Performance Study of a Quadratic Boost Converter

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Circuits and Systems 2024年第2期15卷 13-27页

作者： Modou Badiane Prince abdoul aziz Honadia Oumar Diallo Sadio Fabé Idrissa Barro Department of Physics Semiconductors and Solar Energy Laboratory Faculty of Science and Technique Cheikh Anta Diop University Dakar Senegal Renewable Thermal Energy Laboratory Kaya University Centre Ouagadougou Burkina Faso

Energy is the driving force behind all economic and industrial development. Africa is the least advanced continent in terms of energy consumption and production. Paradoxically, it is the sunniest continent, which is why our objective is to exploit this energy potential in order to produce and use sufficient energy. To achieve this, we are carrying out a series of studies aimed at developing a device capable of converting solar photovoltaic energy into electrical energy. This device is a two-stage converter, the first of which is a quadratic boost and the second a full bridge. Initially, this paper is devoted to studying the performance of the quadratic boost.

关键词： Solar Energy Photovoltaic Efficiency Quadratic Boost Converter

Experimental Study of a Quadratic Boost: The Cascaded Connected Single Switch

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Smart Grid and Renewable Energy 2024年第6期15卷 139-148页

作者： Prince abdoul aziz Honadia Bernard Zouma Adama Ouédraogo Fabé Idrissa Barro Department of Physics and Chemistry Centre Universitaire de Kaya (CU-K) Kaya Burkina Faso Thermal Renewable Energies Laboratory Department of Physics Joseph Ki-Zerbo University Ouagadougou Burkina Faso Semiconductors and Solar Energy Laboratory Department of Physics Faculty of Science and Technique Cheikh Anta Diop University Dakar Senegal

The quadratic boost is studied under its real model. The equations, of the continuous conduction mode, descriptive of this model are established. From these equations, the expressions of the voltage gain and the efficiency are extracted. These two quantities are plotted as a function of the duty cycle in order to appreciate them in different operating points of the transistor. The values of the different components have also been extracted for the fabrication of a prototype of the converter. Thanks to a set of experimental measurements at the input as well as at the output of the prototype converter, the voltage gain and the efficiency could also be observed. These were also plotted for different loads to observe converter behavior. The theoretical curves were compared with the experimental curves which allowed to validate the proposed mathematical models on a large range of duty cycles.

关键词： Voltage Gain Factor Conversion Efficiency Duty Cycle Quadratic Boost

Alternative Phenotypic Profile for B-Cell Abnormality in a Case at Zinder National Hospital

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Open Journal of Blood Diseases 2024年第1期14卷 8-16页

作者： Brah Moustapha Maman Amadou Djibrilla-Almoustapha Moustapha Elhadji-Chefou abdoul-aziz Garba Badé Malam-Abdou Department of Medicine Université André Salifou de Zinder Zinder Niger Department of Medicine H&#244pital National de Zinder Zinder Niger Department of Medicine Université Abdou Moumouni de Niamey Niamey Niger Department of Medicine Université Dan Dicko Dan Koulodo de Maradi Maradi Niger

Introduction: Since it is impossible to establish a diagnosis in the presence of hyperlymphocytosis not secondary to lymphocytic hyperactivation, we considered a B-lymphoid hematopathy with a non-specific phenotypic profile. We report one case of this. Observation: This is a forty-eight (48) year old patient with hyperlymphocytosis at 139,000 elements per cubic millimeter, heterogeneous splenomegaly at 25.6 cm in diameter on abdominal ultrasound without detectable deep or peripheral lymphadenopathy. Peripheral blood cytology shows lymphocyte cell proliferation suggestive of the circulating phase of chronic lymphoproliferative B syndrome. The expression profile of cell membrane markers did not allow for the definition of a specific phenotypic profile. Faced with this immunophenotyping result, we considered a B-lymphoid hemopathy with a non-specific phenotypic profile. After three courses, the MINICHOP treatment was used to achieve partial remission with wasting of more than 80% of the evaluable masses. Conclusion: Despite the contribution of immunophenotyping in the diagnosis of lymphoproliferative syndromes, it is possible to consider the diagnosis of a B-lymphoid hemopathy with a phenotypic non-specific profile of CD45+, monotypic kappa, CD19+, FMC7+, CD22+, CD5−, CD79b−, CD23−, CD43−, CD38−, CD200−.

关键词： Hyperlymphocytosis CLL Immunophenotyping MINICHOP

Local Criteria Used by Farmers to Evaluate the Agronomic Performance and the Fertilizing Capacity of Cowpea Varieties: Diversity, Variability and Proximal Relation with Agronomic Measurements in Contrasted Sahelian Locations

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Agricultural Sciences 2024年第1期15卷 114-131页

作者： Nouhou Salifou Jangorzo abdoul-aziz Saïdou Abou-Soufianou Sadda abdoulaye Moussa Mamoudou Hassane Bil-Assanou Issoufou Département des Sciences du Sol et Télédétection Université Dan Dicko Dankoulodo de Maradi Maradi Niger. Unité Mixte de Recherche “Diversité et Adaptation des Plantes” (UMR DAP) Université Dan Dicko Dankoulodo de Maradi Maradi Niger Centre Imaan de Support en Recherche Transdisciplinaire (Imaan Research) Niamey Niger Institut de Recherche pour le Développement Niamey Niger Université Boubacar BA de Tillabéri Tillabéri Niger Département des Sciences et Techniques de Productions Végétales Université Dan Dicko Dankoulodo de Maradi Maradi Niger

When contributing to participatory research, farmers usually appreciate the performance of cowpea varieties using qualitative scores. The score they attribute to each variety are based on local knowledge. The specific criteria they individually use to attribute a score are not well described. The objectives of this work were to: 1) identify and describe exhaustively the local criteria used by farmers to measure the agronomic performance of cowpea;2) assess the variability and statistical structure of these farmer criteria across local contexts;3) and analyze the association between these farmer criteria and the classical agronomic measurement. To achieve these objectives, an augmented block design was implemented across fifteen locations in the regions of Maradi, Dosso and Tillabéri, representing a diversity of local contexts. From a set of 36 cowpea varieties, fifteen varieties were sown per location, including five varieties (controls) common to all locations. In each location, two replicates were sown in randomized Fisher’s blocks. After agronomic measurement and participatory evaluation (scoring of varieties by farmers), a group survey (focus group) was conducted in each location to identify the criteria considered by farmers to found their discretional scoring of varieties during the participatory evaluation. The analysis of the data identified, across locations, thirteen criteria defined by farmers to characterize the agronomic performance of cowpea. Some of these criteria were different according to location. Farmers ranked the three varieties with the best performance for each agronomical trait (Top 3 varieties). A comparison of the farmer ranking with the ranking based on agronomic measurements revealed similarity and complementary between both methods. This study highlighted the importance of considering both local and scientific knowledge in local varietal evaluations.

关键词： Agronomic Performance Participatory Research Cowpea Farmers’ Criteria

Seasonal Performance of Solar Power Plants in the Sahel Region: A Study in Senegal, West Africa

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Smart Grid and Renewable Energy 2024年第2期15卷 79-97页

作者： Serigne abdoul aziz Niang Mamadou Simina Drame Astou Sarr Mame Diarra Toure Ahmed Gueye Seydina Oumar Ndiaye Kharouna Talla FST D&#233partement de Physique Universit&#233 Cheikh Anta Diop de Dakar Dakar S&#233n&#233gal Laboratoire de Physique de l’Atmosphère et de l’Océan Siméon Fongang Université Cheikh Anta Diop Dakar Sénégal

The main objective of this study is to evaluate the seasonal performance of 20 MW solar power plants in Senegal. The analysis revealed notable seasonal variations in the performance of all stations. The most significant yields are recorded in spring, autumn and winter, with values ranging from 5 to 7.51 kWh/kWp/day for the reference yield and 4.02 to 7.58 kWh/kWp/day for the final yield. These fluctuations are associated with intense solar activity during the dry season and clear skies, indicating peak production. Conversely, minimum values are recorded during the rainy season from June to September, with a final yield of 3.86 kWh/kW/day due to dust, clouds and high temperatures. The performance ratio analysis shows seasonal dynamics throughout the year with rates ranging from 77.40% to 95.79%, reinforcing reliability and optimal utilization of installed capacity. The results of the capacity factor vary significantly, with March, April, May, and sometimes October standing out as periods of optimal performance, with 16% for Kahone, 16% for Bokhol, 18% for Malicounda and 23% for Sakal. Total losses from solar power plants show similar seasonal trends standing out for high loss levels from June to July, reaching up to 3.35 kWh/kWp/day in June. However, using solar trackers at Sakal has increased production by up to 25%, demonstrating the operational stability of this innovative technology compared with the plants fixed panel. Finally, comparing these results with international studies confirms the outstanding efficiency of Senegalese solar power plants, other installations around the world.

关键词： Performance Study Photovoltaic Power Plant Season Variations Senegal

Modeling the Spatio-Temporal Dynamics of Local Context for a Contextualized Diffusion of Agroecological Intensification Options in Niger

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International Journal of Geosciences 2024年第3期15卷 270-301页

作者： Nouhou Salifou Jangorzo Maud Loireau Abou-Souﬁanou Sadda Ousmane Sami Mari abdoul-aziz Saïdou Hassane Bil-Assanou Issoufou Département des Sciences du Sol et Télédétection Université Dan Dicko Dankoulodo de Maradi UMR DAP Maradi Niger Unité mixte de Recherche Diversité et Adaptation des Plantes (UMR DAP) Université Dan Dicko Dankoulodo de Maradi Maradi Niger Institut de Recherche pour le Développement UMR Espace-DEV Université de Perpignan Via Domitia (UPVD) Perpignan France Institut de Recherche pour le Développement Représentation Niamey Niger Centre Imaan de Support en Recherche Transdisciplinaire UMR DAP/UDDM Niamey Niger Département des Sciences et Techniques de Productions Végétales Université Dan Dicko Dankoulodo de Maradi UMR DAP Maradi Niger

Spatio-temporal variability and dynamics in Sahelian agro-pastoral zones make each local situation a special case. These specificities must be considered to guide the dissemination of agricultural options with a view to sustainable development. The territorial scale of municipalities is not sufficient for this necessary contextualization;the scale of the “village terroir” seems to be a better option. This is the hypothesis we put forward in the framework of the Global Collaboration for Resilient Food Systems program (CRFS), i.e. local context is spatially defined by village terroir. The study is based on data collected through participatory mapping and surveys in “village terroirs” in three regions of Niger (Maradi, Dosso and Tillabéri). Then the links between farm managers and their cultivated land, as well as the spatio-temporal dynamics of local context are analyzed. This study provides evidence of the existence and functional usefulness of the village terroir for farmers, their land management and their activities. It demonstrates the usefulness of contextualizing agricultural options at this scale. Their analysis elucidates the links between “terroirs village” and the specific functioning of the agrosocio-ecosystems acting on each of them, thus laying the systemic and geographical foundations for a model of the spatio- temporal dynamics of “village terroirs”. This initial work has opened up new perspectives in modeling and sustainable development.

关键词： Niger Option by Context Local Condition Complex System Multiscale Conceptual Modeling

Assessment of Satisfaction in the Reception and Emergency Department of a Health Center

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Open Journal of Epidemiology 2024年第2期14卷 284-296页

作者： Boubacar Gueye Martial Coly Bop NdéyeMarième Diagne Cheikh Tacko Diop Alioune Badara Tall Papa Gallo Sow Mountaga Dia abdoul aziz Ndiaye Ousseynou Ka Training and Research Unit for Health and Sustainable Development Alioune Diop University of Bambeye Bambey Senegal Dakar Principal Hospital Dakar Senegal Health and Development Institute Cheikh Anta Diop University of Dakar Dakar Senegal

Introduction The main objective of any healthcare establishment must be to ensure the quality of patient care and customer satisfaction. It is necessary to regularly assess patient satisfaction. The aim of this study was to assess the level of satisfaction of customers aged over 18 years attending the emergency department of the health center. Methodology This was a descriptive and analytical cross-sectional study of patients aged 18 years and over, who attended the Samu Municipal emergency department between 02 and 30 May 2023. The satisfaction index was determined using the adapted 2009 SAPHORA-MCO questionnaire and the Likert satisfaction scale. Results A total of 400 patients were surveyed. The average age was 35 years, with a standard deviation of 14.7. Of those surveyed, 51% were women, 87% were educated, 50% lived in Grand Yoff and 59.5% were unemployed. Satisfaction levels linked to perception of the cost of care (72%), waiting time (64.3%), information given to patients (69.1%) and pain management (74 .5%) are fair. On the other hand, the levels of satisfaction linked to administrative procedures (82.5%), staff attitudes towards patients (84%), staff availability (86.4%), patient privacy (89.2%), general atmosphere (87.2%), staff competence (87.3%), and the effectiveness of care (89.4%) were satisfactory. The average waiting time was 38 minutes. However, 32% of patients waited less than 30 minutes and 92% less than an hour. The satisfaction index linked to administration and reception was 72.9% and 79.85%, respectively. The satisfaction index linked to the administration and technical quality of care is equal to 85.8% and 83.7%, respectively. The overall satisfaction index is equal to 80.6%;the level of satisfaction of users of the health structure is satisfactory. Conclusion Patient satisfaction is an essential part of quality care. Patient satisfaction must be based on effective communication from the healthcare team and the creation of a patient-caregive

关键词： Assessment Satisfaction Reception Ad Emergency Department Health Center

Management of Acute Myeloblastic Leukaemia (AML) Treated with Intensive Chemotherapy: Experience in a Single Centre

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Open Journal of Pediatrics 2024年第2期14卷 401-411页

作者： abdoul Karim Doumbia Hawa Konaré Tati Simaga Pierre Togo Oumoulkairi Nana Kouma Hawa Gouro Diall Oumar Coulibaly Adama Dembélé Mohamed Elmouloud Cissé Karamoko Sacko Belco Maiga Aminata Doumbia Kalirou Traoré Ibrahima Cissé Boury Traoré abdoul aziz Diakité Fousseyni Traoré Boubacar Togo Department of Pediatrics University Hospital Gabriel Touré Bamako Mali

Introduction: Acute myeloblastic leukaemia (AML) is a haematological malignancy with a poor prognosis, despite significant therapeutic progress. This study presents the results of AML management in Mali according to GFAOP recommendations. Methodology: This was a retrospective, cross-sectional study. It included patients aged 0 - 15 years treated in the paediatric oncology unit for AML and followed up between January 2016 and December 2020. Results: During the study period, 85 cases of acute leukaemia were diagnosed in the paediatric oncology unit (including 51 cases of ALL), of which 34 cases of AML were included in this study. The majority were boys (59%). The mean age was 8 years, with extremes of 18 months and 15 years. The mean time to diagnosis was 68 days. In 79% of cases, patients were referred by 1st or 2nd level hospitals. Anaemia was observed in 91% of cases, an infectious syndrome in 68%, haemorrhage in 56% and a tumour syndrome in 85%. The haemogram showed hyperleukocytosis in 15% of cases, thrombocytosis in 22% and severe anaemia in 73%. Death occurred in 85% of cases, most often in the context of sepsis or haemorrhage. Conclusion: AML is probably underestimated in Mali and diagnosis delayed, which may be explained by patient-related factors (lack of knowledge, financial constraints) and a cumbersome referral system. These results suggest the need to implement an appropriate diagnostic and therapeutic strategy, with strong involvement of the political authorities.

关键词： Acute Myeloblastic Leukaemia Children Mali