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Fault Diagnosis Method of Rolling Bearing Based on ESGMD-CC and AFSA-ELM

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Structural Durability & Health Monitoring 2024年第1期18卷 37-54页

作者： Jiajie He Fuzheng Liu Xiangyi Geng Xifeng Liang faye Zhang Mingshun Jiang School of Traffic&Transportation Engineering Central South UniversityChangsha410075China project Management Department CRRC Advanced Composites Co.Ltd.Qingdao266108China School of Control Science and Engineering Shandong UniversityJinan250061China

Incomplete fault signal characteristics and ease of noise contamination are issues with the current rolling bearing early fault diagnostic methods,making it challenging to ensure the fault diagnosis accuracy and reliability.A novel approach integrating enhanced Symplectic geometry mode decomposition with cosine difference limitation and calculus operator(ESGMD-CC)and artificial fish swarm algorithm(AFSA)optimized extreme learning machine(ELM)is proposed in this p.p.r to enhance the extraction capability of fault features and thus improve the accuracy of fault ***,SGMD decomposes the raw vibration signal into multiple Symplectic geometry components(SGCs).Secondly,the iterations are reset by the cosine difference limitation to effectively separate the redundant components from the representative ***,the calculus operator is performed to strengthen weak fault features and make them easier to extract,and the singular value decomposition(SVD)weighted by power spectrum entropy(pSE)can be utilized as the sample feature ***,AFSA iteratively optimized ELM is adopted as the optimized classifier for fault *** superior performance of the proposed method has been validated by various experiments.

关键词： Symplectic geometry mode decomposition calculus operator cosine difference limitation fault diagnosis AFSAELM model

Intelligent Fault Diagnosis Method of Rolling Bearings Based on Transfer Residual Swin Transformer with Shifted Windows

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Structural Durability & Health Monitoring 2024年第2期18卷 91-110页

作者： Haomiao Wang Jinxi Wang Qingmei Sui faye Zhang Yibin Li Mingshun Jiang phanasindh paitekul The Institute of Marine Science and Technology Shandong UniversityQingdao26623China The School of Control Sciences and Engineering Shandong UniversityJinan250061China Thailand Institute of Scientific and Technological Research Amphoe Khlong LuangPathum Thani12120Thailand

Due to their robust learning and expression ability for complex features,the deep learning(DL)model plays a vital role in bearing fault ***,since there are fewer labeled samples in fault diagnosis,the depth of DL models in fault diagnosis is generally shallower than that of DL models in other fields,which limits the diagnostic *** solve this problem,a novel transfer residual Swin Transformer(RST)is proposed for rolling bearings in this *** has 24 residual self-attention layers,which use the hierarchical design and the shifted window-based residual *** with transfer learning techniques,the transfer RST model uses pre-trained parameters from ImageNet.A new end-to-end method for fault diagnosis based on deep transfer RST is ***,wavelet transform transforms the vibration signal into a wavelet time-frequency *** signal’s time-frequency domain representation can be represented ***,the wavelet time-frequency diagram is the input of the RST model to obtain the fault ***,our method is verified on public and self-built *** results show the superior performance of our method by comparing it with a shallow neural network.

关键词： Rolling bearing fault diagnosis transformer self-attention mechanism

Determination of the Series Resistance of a Series Vertical-Junction Silicon (N+/p.p.) Solar Cell under polychromatic Illumination and Magnetic Field: Effect of Optimum Thickness

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Journal of Modern physics 2024年第10期15卷 1543-1554页

作者： Dibor faye Babou Dione Mountaga Boiro p.p. Diop Semiconductor and Solar Energy Laboratory Department of Physics Cheikh Anta Diop University Dakar Senegal

By solving the magneto-transport equation for excess minority charge carriers in the base of the series vertical-junction silicon cell, the phenomenological parameters of the cell can be determined from the boundary conditions. photocurrent density and photovoltage are determined for each value of applied magnetic field and corresponding optimum thickness, to establish the current-voltage characteristic (Jph(Sf, Sb, z, B, Hop)-Vph(Sf, Sb, z, B, Hop) of the silicon cell under polychromatic illumination. This study will make it possible to reduce the material used (by reducing the optimum thickness), which will help to lower prices. It will also enable us to reduce betting effects (lower series resistance), thereby boosting solar cell efficiency.

关键词： Series Vertical Junction Silicon Cell Static Regime Magnetic Field Optimum Thickness Series Resistance

Study of the Biological Quality of the Water in the Manantali Dam Reservoir: Analysis of the Fish Fauna and plankton Communities

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Journal of Agricultural Chemistry and Environment 2024年第1期13卷 100-114页

作者： Joseph Mbeur faye Saïdou Ndao Louis Eugène Victor Sambou Laboratory of Water and Environment Sciences and Technologies (LaSTEE) Polytechnic School of Thies (EPT) Thies Senegal UFR Sciences et Technologies (SET) University Iba Der Thiam of Thies (UIDT) Thies Senegal

The aim of this study of the Manantali dam reservoir is to investigate the biological quality of the water through inventories and analysis of the ichthyofauna and planktonic communities (zooplankton and phytoplankton). Inventories of ichthyofauna and plankton communities were carried out quarterly from 2003 to 2022. The fish p.p.lations studied on the basis of bioindicators (species richness, diversity index, equitability index, diversification index) identified 29 species belonging to 10 families. The Cichlidae family is the most represented, while the Schilbeidae and Tetraodontioae families are less represented in terms of number of species. The species Hydrocynus forskalii and Brycinus nurse with relative abundances of 40.12% and 21.4% respectively, both from the family Alestidae, are the most abundant. The species H. forskalii has a frequency of occurrence of 100%. The specific diversity index of 2.9 and the equitability index of 0.6 show an average diversity of fish species. The diversification index of 2.9 indicates a theoretical number of habitats of 2 to 3. The planktonic community is made up of zooplankton and phytoplankton. The inventory of zooplankton shows the presence of 28 zooplankton species belonging to 9 families of the three zooplankton groups Rotifera, Cladocera and Cop.p.da. Analysis of the frequencies of occurrence of the various taxa showed that the characteristic species of Lake Manantali are the omnipresent rotifers Keratella cochlearis, Keratella quadrata and Trichocerca chattoni. For phytoplankton, the inventories carried out show the presence of 65 species belonging to 5 families (Chlorophycees, Diatomees, Dinophycees, Chrysophycees and Cyanophycees). An analysis of the frequency of occurrence of the various taxa shows that the characteristic species of Lake Manantali are Chlorophycees, with 7 species: Desmidium baileyi, Micrasterias alata, Sphaerocystis schroeteri, Spondylosium sp., Staurastrum heimii, Staurastrum subanchora, Staurodesmu

关键词： Inventory Fish Zooplankton phytoplankton Diversity Manantali

Infantile Spinal Muscular Atrophy at the Albert Royer National Children’s Hospital Center in Dakar

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Open Journal of pediatrics 2024年第3期14卷 514-521页

作者： guillaye Diagne Khadim Bop Sofiatou Dieye Arame faye Fatou Ly Amadou Lamine Fall pediatrics Ward of pikine Hospital Pikine Senegal pé diatrics Ward of Albert Royer National Hospital Dakar Senegal

Introduction: Infantile spinal muscular atrophy (ISA) is an autosomal recessive disease caused by primary degeneration of cells in the anterior horn of the spinal cord, leading to muscle weakness and hypotonia. Its incidence is estimated at 1 in 6000 births worldwide. In Africa, particularly in Senegal, there are few studies interested on this pathology. We therefore deemed this study necessary, which set itself the objective of describing the diagnostic, therapeutic and progressive aspects of infantile spinal muscular atrophy at the Albert Royer National Children’s Hospital Center in Dakar (CHNEAR). Methodology: We conducted a retrospective descriptive study over a period of two (2) years from December 2020 to December 2022. Included were all hospitalized patients in whom the diagnosis of spinal muscular atrophy was made with or without genetic confirmation. The data were collected on a pre-established form then entered and analyzed with the following software: Excel 2013 and R version 4.1.3. Results: During our study period, 2100 children were hospitalized, the annual incidence was 0.76%. The average age of our patients was 9 ± 9 months with a range of 3 months to 32 months and the median was 6.5 months. The sex ratio was 7. The notion of family consanguinity was found in 62.5% of cases and the notion of ISA in the family in 25% of cases. Hypotonia and respiratory distress were found at the forefront in equal proportions (50% of cases). Electromyogram (EMG) was performed in 3 patients (37.5%). Symptomatic medical treatment was administered in 100% of patients, 04 patients had benefited from respiratory physiotherapy, i.e. 50% of cases, and genetic counseling was carried out in one patient (12.5%). The evolution was immediately favorable in 2 patients or 25% of cases, unfavorable in 75% of cases with a death rate of 50% and the average age of death was 5.5 months ± 1 with extremes ranging from 3 to 7 months. Conclusion: The number of Infantile spinal muscular atrop

关键词： Spinal Muscular Atrophy Child Hypotonia Dakar

Hydrogeophysical and Structural Investigations Using VES: A Case Study of Dosso Region in the Southwestern part of the Meso-Cenozoic Iullemmeden Basin (Southwestern Niger)

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Open Journal of Geology 2024年第1期14卷 50-80页

作者： Abdou Ali Ibrahim Huguette C. Emvoutou Alain Zanga Konaté Moussa Serigne faye Department of Life and Earth Sciences Ecole Normale Supérieure Université Abdou Moumouni Niamey Niger Department of Earth Sciences Faculty of Sciences University of Douala Douala Cameroon Department of Geology Faculty of Sciences and Techniques University Cheikh Anta Diop of Dakar Dakar Senegal Department of Geology Faculty of Sciences and Techniques Université Abdou Moumouni Niamey Niger

A regional study connecting geolelectrical surveys with geology and hydrogeology was carried out in the western part of the Iullemmeden basin, precisely in the Dosso region in Niger. One hundred and four (104) vertical electrical sounds have been realized, among them nineteen representative were thus be used as parametric surveys. The local resistivity values of the geological formations of Quaternary range from 100 Ω⋅m to 1000 Ω⋅m (sands and lateritic sandstones). The Oligo-Miocene formation of the Continental terminal (Ct) shows resistivity values ranging from 1 to 5 Ω⋅m (brackish groundwaters) to 1500 Ω⋅m (clay sandstones) while the Upper Cretaceous formation of the Continental “hamadien” (Ch) indicates values ranging from 20 Ω⋅m (sandy clay) to 5000 Ω⋅m (clayey sandstones). The geological formations of paleocene have values from 2 Ω⋅m (marls) to 60 Ω⋅m (calcareous marl), while the precambrian basement exhibits values of granite around 300 Ω⋅m to 60,000 Ω⋅m. The update of the structural settings reveals many faults in the study area which explain both the shape of the basin and the geometry of the aquifers. Tectonics is also consistent with the hydraulic characteristics of aquifers. In addition, brackish groundwaters were identified as perched aquifer groundwaters in different depths in Dosso region. They probably come from the marine brines during the regression of the paleocene Sea.

关键词： Vertical Electrical Soundings Continental Terminal Continental “Hamadien” Brackish Groundwaters Iullemmeden Basin Dosso Region

Enhancing precision in Radiotherapy delivery: Validating Monte Carlo Simulation Models for 6 MV Elekta Synergy Agility LINAC photon Beam Using Two Models of the GAMOS Code

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World Journal of Nuclear Science and Technology 2024年第2期14卷 146-163页

作者： Nogaye Ndiaye Oumar Ndiaye p.p. Macoumba faye Kodjo Joël Fabrice N’guessan Djicknack Dione Khady Sy Moussa Hamady Sy Jean paul Latyr faye Alassane Traoré Ababacar Sadikhe Ndao Institute of Applied Nuclear Technology University Cheikh Anta Diop Dakar Senegal International Cancer Center of Dakar Dakar Senegal Department of physics Faculty of Sciences and Technology University Cheikh Anta Diop Dakar Senegal

The most crucial requirement in radiation therapy treatment planning is a fast and accurate treatment planning system that minimizes damage to healthy tissues surrounding cancer cells. The use of Monte Carlo toolkits has become indispensable for research aimed at precisely determining the dose in radiotherapy. Among the numerous algorithms developed in recent years, the GAMOS code, which utilizes the Geant4 toolkit for Monte Carlo simula-tions, incorporates various electromagnetic physics models and multiple scattering models for simulating particle interactions with matter. This makes it a valuable tool for dose calculations in medical applications and throughout the patient’s volume. The aim of this present work aims to vali-date the GAMOS code for the simulation of a 6 MV photon-beam output from the Elekta Synergy Agility linear accelerator. The simulation involves mod-eling the major components of the accelerator head and the interactions of the radiation beam with a homogeneous water phantom and particle information was collected following the modeling of the phase space. This space was po-sitioned under the X and Y jaws, utilizing three electromagnetic physics mod-els of the GAMOS code: Standard, penelope, and Low-Energy, along with three multiple scattering models: Goudsmit-Saunderson, Urban, and Wentzel-VI. The obtained phase space file was used as a particle source to simulate dose distributions (depth-dose and dose profile) for field sizes of 5 × 5 cmp>2p> and 10 × 10 cmp>2p> at depths of 10 cm and 20 cm in a water phantom, with a source-surface distance (SSD) of 90 cm from the target. We compared the three electromagnetic physics models and the three multiple scattering mod-els of the GAMOS code to experimental results. Validation of our results was performed using the gamma index, with an acceptability criterion of 3% for the dose difference (DD) and 3 mm for the distance-to-agreement (DTA). We achieved agreements of 94% and 96%, respective

关键词： GAMOS Monte Carlo LINAC Radiotherapy Dose Distribution phase Space Gamma Index 6 MV photon Beam

Humoral Response and Tolerance of Vaccination against SARS-CoV-2 in Adults Senegalese patients Undergoing Hemodialysis: A Multicenter prospective Study

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Open Journal of Nephrology 2024年第1期14卷 70-80页

作者： Lot Nehemie Motoula Latou Moustapha Mbow Modou Ndongo Gnagna faye Gora Lo Sidy Mohamed Seck Department of Nephrology and Dialysis Military Hospital of Ouakam Dakar Senegal Immunology Laboratory Military Hospital of Ouakam Dakar Senegal Department of Nephrology and Dialysis Regional Hospital of Kedougou Kedougou Senegal Department of Nephrology Idrissa Pouye General Hospital Dakar Senegal Bacterioloy and Virology Laboratory CMIA Dakar Senegal IRL-3189 ESS/UGB/CNRS/UCAD/CNRST/USTB Faculty of Health Sciences University Gaston Berger Saint-Louis Senegal

Introduction: Following the COVID-19 pandemic, vaccination has been proposed in several countries as the main preventive measure despite very limited data, particularly in dialysis patients. We conducted this study to assess the immunological response to vaccination in Senegalese hemodialysis patients. patients and Methods: We conducted a prospective study, in two dialysis centers in Dakar from March 30p>thp> to August 30p>thp>, 2021 including patients on hemodialysis for >6 months, vaccinated against SARS-CoV-2 according to the vaccination schedule recommended by WHO. A vaccine response was considered positive when seroconversion was observed after one dose of vaccine. The clinical efficacy of immunization was defined as the absence of new COVID-19 infection in patients who received a complete vaccination. Results: Among the 81 patients included in the study, 7.4% had anti-Spike IgM antibodies before their first vaccination. Seroprevalence of IgM antibodies was 38.3% one month after the first vaccine dose (at M1) and 8.6% one month after the second dose (at M4). Anti-Spike IgG antibodies were present in 40.3% of patients before vaccination, in 90.1% at M1, and in 59.7% at M4. Among patients previously infected with SARS-CoV-2, 10.2% had IgM antibodies at M0, 31.6% at M1, and 10.5% at M4 post-vaccination. Similarly, seroprevalences of IgG antibodies in this subgroup were 31.5%, 61.3%, and 50.0% respectively at M0, M1, and M4 post-vaccination. A comparison of seroconversion rates between M0 and M4 showed significant differences only for IgG in COVID-19 naive patients. Mean duration in dialysis and the existence of previous COVID-19 infection were associated with patients’ vaccinal response after the two doses. Age, gender and the use of immunosuppressive treatment did not influence post-vaccinal antibody production. Conclusion: Vaccination against COVID-19 in Senegalese hemodialysis patients induced a low seroconversion rate but it was well tolerated. M

关键词： SARS-Cov2 Vaccination Humoral Response Tolerance Hemodialysis Senegal

Lithostructural Control of the Gold Mineralization of the Douta permit of African Star Resources (Kédougou-Kéniéba Inlier, Southeastern Senegal)

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International Journal of Geosciences 2024年第4期15卷 303-333页

作者： Masse Ndour p.p. Moussa Ndiaye Koffi Félix Ekra Alain Ndong Malick faye pierre Ndour African Star Resources Yoff Dakar S&#233n&#233gal Dé partement de G&#233ologie Universit&#233 Cheikh Anta Diop Dakar S&#233n&#233gal

The Douta permit of African Star Resources/Thor Explorations, located in the southeast of Senegal, in the Kédougou-Kéniéba Inlier (western part of the West African Craton), is dominated to the East by metasedimentary formations such as greywackes, shales, graphitic shales, quartzites, cherts, claystones and breccias characteristic of the Dialé-Daléma basin. To the West, the mafic formations of the Mako volcanic belt are the most common. Metasedimentary rocks are associated with metavolcanosedimentary terms found at the contact zones between the two (2) Birimian groups. These different geological formations are cut by mafic dolerite and gabbro sills and/or dykes, as well as quartz and microgranite veins. The Douta gold project is crossed from North to South by the MTZ (Main Transcurrent Zone), generally oriented NE-SW and becoming N-S towards the North. The permit is characterized by several shear corridors. The rocks are affected by brittle, brittle-ductile to ductile deformations. The gold mineralization is hosted by a NE-trending shear corridor called the Makosa corridor (Makosa shear zone), therefore sub-parallel to the MTZ. It has a subvertical dip (75˚ to 85˚ to the NW). It is associated with a hydrothermal phase characterized by quartz-sericite-epidote-fine, disseminated pyrite and arsenopyrite ± albite ± chlorite paragenesis. These minerals testify to the existence of a low degree of metamorphism (greenschist facies, epizonal domain) in the area. However, metamorphism reaches amphibolite facies in some places, particularly in the vicinity of intrusive bodies, with the presence of hornblende (amphiboles) and plagioclase. The gold mineralization is mainly hosted by two (2) metasedimentary lithological units: meta-greywackes and shales.

关键词： Douta Kédougou-Kéniéba Inlier Senegal Metasedimentary MTZ Control Gold Mineralization Makosa Corridor