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Smart Grid and Renewable Energy 2023年第5期14卷 73-84页

作者： Ibrahima Gueye mamadou sall Abdoulaye Kebe Laboratoire L3EPI Ecole Superieure Polytechnique Université Cheikh Anta Diop Dakar Senegal

In this study, we investigate the performance of a boost converter regulating its output voltage using two control methods: Proportional-Integral (PI) control and neural control. Both methods are implemented on a simulation platform (Matlab/Simulink) and evaluated in terms of accuracy, response speed, and robustness to disturbances. Indeed, the output voltage of converters exhibits imperfections that require a control method to optimize efficiency when applying a variable load. Results show that neural control offers superior performance in terms of accuracy and response time, with faster and more precise regulation of the output voltage. On the other hand, PI control proves to be more robust against disturbances. These findings can help guide the selection of the appropriate control method for a boost converter based on the specific requirements of each application.

关键词： Chopper PI Control Neural Control

Comparative Study between the PID Regulator and the Fuzzy Regulator Applied to the Operation of a Brushless DC Motor

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Energy and Power Engineering 2021年第11期13卷 365-376页

作者： mamadou sall Abdoulaye Kebe Ibrahima Gueye Moustapha Diop Laboratoire L3EPI Ecole Supérieure Polytechnique Ecole Normale Supérieure d’Enseignement Technique et Professionnel Université Cheikh Anta Diop Dakar Senegal

This paper presents the results of research on speed regulation of a brushless DC motor. This is mainly a comparative study between a PID regulator and a fuzzy regulator applied to the operation of this type of engine in order to find the best control. The BLDC engine must operate under various speed and load conditions with improved performance and robust and complex speed control. Because of this complexity, the traditional PID command encounters difficulties in controlling the speed of a BLDC. Another control technique is currently developing and is producing good results. This is the fuzzy controller that handles process control problems, that is, managing a process based on a given set point per action on the variables that describe the process. To achieve the desired results, the brushless DC machine model will be studied. With the model obtained, both types of regulator will be tested. A synthesis of the observed comparison results will enable a conclusion to be drawn on the performance of the two types of regulators driving a BLDC (Brushless DC).

关键词： Fuzzy Logic Controller PID Controller Brushless DC Motor DC Motor

Solar Controller with Automatic Search Technology for the Maximum Power Point with Autonomy Display

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Energy and Power Engineering 2022年第9期14卷 509-522页

作者： mamadou sall Ousmane Sow Sega Gueye Gora Diop Lemrabott Habiboullah mamadou Wade Gregoire Sissoko Ecole Polytechnique de Thiè s Thi&egrave s S&eacute né gal Institut Universitaire de Technologie. Université Iba Der THIAM de Thi&egrave s S&eacute né gal Groupe International de Recherche en Energie Renouvelable(GIRER) Dakar S&eacute né gal Ecole Supérieure Multinationale de Té lé communication Dakar S&eacute né gal

In our work, we have been interested in conducting technological research on the use of photovoltaic energy for lighting. In fact, we have produced a stand-alone photovoltaic system with automatic search for the maximum power point, consisting of a photovoltaic module, a solar regulator, a storage battery and a digital control by microcontroller. The solar field is connected to the input of the regulator and the battery to its output. When the battery voltage is lower than the regulation voltage, the controller operates the photovoltaic generator at maximum power Pmpp and transfers this power to the output. In addition to the protection function, this regulator ensures tracking of the maximum power point (MPPT) and allows the photovoltaic generator to deliver its power whatever the variation of climatic conditions (sunshine and temperature). The main role of the solar regulator is the continuous monitoring of the state of charge of the battery to ensure its protection against overcharging and excessive discharging, the coupling and decoupling of the user as well as its maintenance. The principle of operation is based on controlling a DC-DC converter by a rectangular “PWM” signal generated by a PIC16F874 microcontroller which also controls the entire system. The results of simulation after realization were presented to illustrate the operation of the regulator by curves.

关键词： Index Terms-Battery Charge/Discharge Regulator PIC16FC874

Performance of Twelve Mass Transfer Based Reference Evapotranspiration Models under Humid Climate

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Journal of Water Resource and Protection 2017年第12期9卷 1347-1363页

作者： Koffi Djaman Komlan Koudahe mamadou sall Isa Kabenge Daran Rudnick Suat Irmak Department of Plant and Environmental Sciences New Mexico State University Agricultural Science Center Farmington USA ADA Consulting Africa Lomé Togo Research Scientist Institut Senegalais de Recherches Agricoles Centre de Saint Louis Saint Louis Sénégal Department of Agricultural and Biosystems Engineering Makerere University Kampala Uganda Department of Biological Systems Engineering University of Nebraska-Lincoln Chase Hall Lincoln USA

Reference evapotranspiration is very important parameter in the hydrological, agricultural and environmental studies and is accurately estimated by the FAO Penman-Monteith equation (FAO-PM) under different climatic conditions. However, due to data requirement of the FAO-PM equation, there is a need to investigate the applicability of alternative ETo equations under limited data. The objectives of this study were to evaluate twelve mass transfer based reference evapotranspiration equations and determine the impact of ETo equation on long term water management sustainability in Tanzania and Kenya. The results showed that the Albrecht, Brockamp-Wenner, Dalto, Meyer, Rohwer and Oudin ETo equations systematically overestimated the daily ETo at all weather stations with relative errors that varied from 34% to 94% relative to the FAO-PM ETo estimates. The Penman, Mahringer, Trabert, and the Romanenko equations performed best across Tanzania and the South Western Kenya with root mean squared errors ranging from 0.98 to 1.48 mm/day, which are relatively high and mean bias error (MBE) varying from -0.33 to 0.02 mm/day and the absolute mean error (AME) from 0.79 to 1.16 mm/day. For sustainable water management, the Trabert equation could be adopted at Songea, the Mahringer equation at Tabora, the Dalton and/or the Rohwer equations at Eldoret, the Romanenko equation at Dodoma, Songea and Eldoret. However, regional calibration of the most performing equation could improve water management at regional level.

关键词： Reference Evapotranspiration Mass Transfer Eastern Africa Water

Back Illuminated N/P/P<sup>+</sup>Bifacial Silicon Solar Cell under Modulated Short-Wavelength: Determination of Base Optimum Thickness

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Energy and Power Engineering 2021年第5期13卷 207-220页

作者： mamadou sall Dianguina Diarisso Mame Faty Mbaye Fall Gora Diop Mor Ndiaye Khady Loum Gregoire Sissoko Laboratory of Semiconductors and Solar Energy Physics Department Faculty of Science and Technology Cheikh Anta Diop University Dakar Senegal University Institute of Technology University of Thiès Thiès Sénégal Ecole Polytechnique de Thiès Thiès Sénégal

A bifacial silicon solar cell under monochromatic illumination in frequency modulation by the rear side is being studied for the optimization of base thickness. The density of photogenerated carriers in the base is obtained by resolution of the continuity equation, with the help of boundary conditions at the junction surface (n+/p) and the rear face (p/p+) of the base. For a short wavelength corresponding to a high absorption coefficient, the AC photocurrent density is calculated and represented according to the excess minority carrier’s recombination velocity at the junction, for different modulation frequency values. The expression of the AC recombination velocity of excess minority carriers at the rear surface of the base of the solar cell is then deduced, depending on both, the absorption coefficient of the silicon material and the thickness of the base. Compared to the intrinsic AC recombination velocity, the optimal thickness is extracted and modeled in a mathematical relationship, as a decreasing function of the modulated frequency of back illumination. Thus under these operating conditions, a maximum short-circuit photocurrent is obtained and a low-cost bifacial solar cell can be achieved by reducing material (Si) to elaborate the base thickness.

关键词： Bifacial Silicon Solar Cell AC Recombination Velocity-Base Thickness Short-Wavelength

Trend Analysis in Rainfall, Reference Evapotranspiration and Aridity Index in Southern Senegal: Adaptation to the Vulnerability of Rainfed Rice Cultivation to Climate Change

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Atmospheric and Climate Sciences 2017年第4期7卷 476-495页

作者： Komlan Koudahe Koffi Djaman Ansoumana Bodian Suat Irmak mamadou sall Lamine Diop Alpha B. Balde Daran R. Rudnick Direction des Filières Végétales (DFV) MAEH Lomé Togo Department of Plant and Environmental Sciences New Mexico State University Agricultural Science Center at Farmington Farm-ington NM USA Laboratoire Leïdi “Dynamique des territoires et développement” Université Gaston Berger (UGB) Saint Louis Sénégal Department of Biological Systems Engineering University of Nebraska-Lincoln Chase Hall Lincoln NE USA Research Scientist Institut Senegalais de Recherches Agricoles Centre de Saint Louis Saint Louis Sénégal UFR S2ATA Université Gaston Berger (UGB) Saint Louis Sénégal Institut Sénégalais de Recherches Agricoles Bambey Sénégal

Rainfall and evapotranspiration are two vital elements for food production under rainfed agriculture. This study aims at investigating the combined changes in these variables in the form of aridly index in the southern Senegal. The temporal trends in annual and monthly (from May to October) aridity index, rainfall and evapotranspiration are examined and adaptation strategies to the vulnerability of rainfed rice cultivation to the changes are developed. The results show a significant decreasing trend in annual rainfall at all study locations for the period 1922-2015. When analyzing the trends in sub-periods, there are two clear patterns in the annual rainfall series: a decreasing trend for the period 1922-1979 and a reversal increasing trend for the period 1980-2015. An increasing trend is also observed in annual reference evapotranspiration. The results reveal that the region will be drier with a significant increase in aridity at the annual and most monthly series. Appropriate adaptation strategies should be implemented to diminish the adverse influence of the increasing aridity on rice productivity for a sustainable agriculture.

关键词： Variation Evapotranspiration Rainfall Aridity Index Senegal Rainfed Rice

Congenital Cervico-Mandibular Cystic Lymphangioma in Pediatric Surgical Setting in Guinea

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Open Journal of Pediatrics 2024年第1期14卷 164-173页

作者： Thierno Saïdou Barry Mohamed Lamine Sadou Sacko Balla Keita Aissatou Bailo Balde mamadou Alpha Diallo Moussa Conde Ibrahima Kalil Dioubate Mory Sangare Salamata sall Mariama Dalanda Diallo Daniel Agbo-Panzo Pediatric Surgery Department Donka National Hospital (HND) of Conakry University Hospital (Gamal Abdel Nasser University of Conakry (UGANC) of Guinea) Conakry Guinea Hadja Bilguissou BARRY Medical-Surgical Clinic (HBB) Conakry Guinea Albert Royer Children’s Service Cheikh Anta DIOP University (UCAD) Dakar Senegal Surgery Department of the Regional Hospital Center of Ziguinchor (CHRZ) Ziguinchor Senegal

Introduction: Cystic lymphangiomas are rare benign malformative tumors of the lymphatic system of obscure etiopathogenesis. The cervico-facial location remains the most common (75%). Although benign, these tumors remain potentially fatal, due to possible compression of the upper aero-digestive tract. The aim of this work is to study the epidemiological, diagnostic and therapeutic characteristics of cervico-mandibular congenital cystic lymphangiomas in the pediatric surgery department of the Donka National Hospital (HND) Conakry. Patients and methods: This is a retrospective and descriptive study of 13 files lasting 7 years from January 2015 to December 31, 2021. The files of children whose age is less than or equal to 15 years operated on cervical tumor with histological evidence of cystic lymphangioma were retained. The data were analyzed using SPSS statistical software 21 and anonymously. Results: The incidence of this study was 1.86 cases per year and a sex ratio of 0.62 in favor of girls. The average age was 8 months 19 days. In the antecedents, we only find poorly monitored pregnancies. The average size of the tumors was 11.85 cm. Cervical ultrasound and standard x-ray of the cervical mass were the only examinations performed. Total surgical excision of the cervical tumor was performed in all patients. The mass was polycystic on exploration. The histological examination of the surgical specimens was in favor of a cystic lymphangioma. The surgical consequences were simple in 11 patients (84.62%) and complicated by parietal suppuration in 2 cases (15.38%). There were no cases of recurrence after one year of follow-up. Conclusion: Cervico-mandibular cystic lymphangiomas are the most frequent locations of congenital lymphangiomas in children. Their severity is linked to the risk of compression of the aero-digestive tracts. Their diagnosis must be confirmed by the histology of the surgical specimen. Despite the therapeutic arsenal, excision of the cystic mass remain

关键词： Congenital Cystic Lymphangioma (LKC) Child Pediatric Surgery Guinea

Screening, Treatment and Control of High Blood Pressure on Five Sites in Mali

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World Journal of Cardiovascular Diseases 2024年第5期14卷 322-332页

作者： mamadou Touré Sagara Ibrahima Youssouf Camara Hamidou Oumar Bâ Ibrahima Sangaré Djénébou Traoré Noumou Sidibé Fousseyni Samassékou Massama Konaté Coumba Thiam Doumbia Asmaou Maiga Réné-Marie Dakouo Hamidou Camara Sako Mariam Sidibé Samba Adama Sogodogo Boubacar Diarra Boubacar Sonfo Aladji Traoré mamadou Diakité Ilo Bella Diall Ichaka Menta Departement of Cardiology University Hospital Gabriel Tour&#233 Bamako Mali Departement of Cardiology Cardiology University Hospital Sidy Bocar Sall Kati Mali Internal Medecine University Hospital Point G Bamako Mali Departement of Cardiology Cardiology University Hospital &#8220H&#244pital du Mali&#8221 Bamako Mali Departement of Cardiology Cardiology University Hospital Mother-Children Bamako Mali

Introduction: High blood pressure is defined as blood pressure greater than or equal to 140 mm Hg for systolic and or 90 mm Hg for diastolic. It constitutes a major public health problem, the leading chronic disease in the world. The objective was to determine the prevalence, treatment rate and control of hypertension. Methods: This was a cross-sectional and descriptive study which took place over a period of 6 months in a hospital environment and in the general population. Results: Of the 1000 participants, 637 had hypertension, giving a prevalence of 63.70% with a female predominance. Thirty-three percent (33%) were unaware of their high blood pressure. The age group 60 and more was the most represented (44%). A proportion of 33 and 23.20 were overweight and obese participants, respectively. Male subjects were more overweight than female, unlike obesity which was more common among female subjects. Sixty-two percent (62%) of hypertensives were treated, of whom 44% were non-compliant. The excessively high cost and consumption of medications as needed were the main factors in therapeutic non-compliance. Twenty-two percent (22%) of all hypertensive patients and 35% of treated hypertensive patients were controlled. Women were more treated but less observant and less controlled than men. Therapeutic coverage and combination therapy rates were lower in rural areas. Hypertensives who had a high level of education were better treated and controlled than those who had no level. Conclusion: High blood pressure remains a real public health problem in Mali. It is more common in people aged 60 and over and in females. One in three hypertensives were unaware of their hypertension. The majority received antihypertensive treatments, but only a minority of them had their hypertension controlled.

关键词： High Blood Pressure Screening Control Rate Mali

Epidemiological, Clinical and Therapeutic Aspects of Bladder Tumors in a Schistosomiasis-Endemic Country

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Open Journal of Urology 2024年第3期14卷 151-159页

作者： Amadou Kassogue Idrissa Sissoko Alkadri Diarra Moussa Salifou Diallo Daouda Sangare Boureima Coulibaly Philippe Togo Albacaye Sember Mahamadou Traore Salia Coulibaly mamadou Lamine Diakite Urology Department Pr Bocar Sidy Sall University Hospital Kati Mali Urology Department Luxembourg University Hospital Bamako Mali Medical Imaging Department Pr Bocar Sidy Sall University Hospital Kati Mali Urology Department Point G University Hospital Bamako Mali

Introduction: Bladder tumors are common in our country;Mali is a bilharzial endemic country. In our context, urinary bilharzia is common, and bladder tumors arouse particular interest in the field of urological oncology, because of their frequency, their diagnosis, their difficulty in management and their histological particularity. The objective of our work was to study the epidemiological, clinical and therapeutic aspects of bladder tumors. Materials and Methods: This is a cross-sectional, descriptive study with a retrospective and prospective collection that took place over 3 years from January 1, 2020 to December 31, 2022. Results: We identified 316 cases of bladder tumors during this period. Bladder tumors are a common pathology representing 35.95% of all hospitalized patients, and occupying the 1st rank of tumors in urology in the Urology Department of the Pr Bocar Sidy sall University Hospital in Kati. Bladder tumors were more common in men with 56.33%. The average age of our patients was 50 years ± 25.8 years and the extreme ages were 20 and 87 years. Urinary schistosomiasis, considered a predisposing factor, was found in 66.78% of cases in our patients as a history. Transurethral resection of the bladder was performed in 100% of our patients, nephrostomy in 1.90% of cases, ureterostomy in 1.58% of cases, Bricker type urinary diversion in 1.27% of cases, and a neobladder in 0.32% of cases. Squamous cell carcinoma is the dominant histological type (88.29%). The postoperative outcome was 99% favorable after resection. Conclusion: Bladder tumors were mainly tumors infiltrating the bladder muscle. The main risk factor was urinary bilharzia. Squamous cell carcinoma is the most common histological type with a diagnostic delay, thus limiting radical treatment after resection of the bladder tumor.

关键词： TURB Squamous Cell Carcinoma Urinary Schistosomiasis

Ureteroscopy with Holmium: YAG Laser—A Initial Study in the Urology Department of the Pr Bocar Sidy sall University Hospital of Kati

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Open Journal of Urology 2024年第4期14卷 207-216页

作者： Amadou Kassogue Idrissa Sissoko Daouda Sangare Moussa Salifou Diallo Hamed Sylla Mahamadou Traore Boureima Coulibaly Salia Coulibaly Modibo Diakite Modibo Togola Fadima Tall Ilias Guindo Ben Naoum Kamel mamadou Lamine Diakite Urology Department University Hospital of Pr Bocar Sidy Sall Kati Mali Radiology Department University Hospital of Pr Bocar Sidy Sall Kati Mali Anesthesy and Reanimation Department University Hospital of Pr Bocar Sidy Sall Kati Mali Urology Department University Hospital Nimes France Urology Department University Hospital of Point G Bamako Mali

Introduction: Ureteroscopy is a minimally invasive endoscopic surgery which provides access to the ureter, pyelon and calyceal cavities via the urethra and the bladder. Laser ureteroscopy uses the laser as an energy source to treat the stone and eliminate it naturally. Minimally invasive endoscopic methods are struggling to become popular in sub-Saharan African countries, especially for the upper urinary tract. The objective of our work was to report the results of our first laser ureteroscopy experience in the department. Materials and Methods: This was a prospective and descriptive study running from December 1, 2023 to February 19, 2024. Included in our study was any case of upper urinary tract stone operated by Laser ureteroscopy. The characteristics of the lithiasis were determined by CT scan. Sterilization of urine was verified by carrying out a cytobacteriological examination of urine. Ureteral lithiasis was approached by semi-rigid ureteroscopy. Renal lithiasis was immediately addressed by flexible ureteroscopy. Ureteroscopy was coupled with a Holmium YAG laser. A double J ureteral catheter was placed after the operation. A 230 µm laser fiber was used in each case with a generator with a power of 35 watts (Storz Calculase III type). An access sheath was used in all cases of flexible ureteroscopy. The parameters studied were: sociodemographic characteristics, lithiasis (site, size, number, density, topography), type of anesthesia, duration of laser use, duration of intervention, postoperative outcomes. Data entry and analysis were carried out using the software (Word 2016 and SPSS). Result: We collected 30 cases of laser ureteroscopy. The average age was 37 years with extremes of 9 and 79 years. The male gender was more represented. The most common age group was 24-39 years old. Renal colic was the most frequent reason for admission, 12 patients (40%). On physical examination, lumbar tenderness was present in 47% (14 patients). ECBU was positive in 4 patients

关键词： Ureteroscopy Semi-Rigid Flexible Holmium YAG Laser