检索结果-南通市图书馆

Polycrystalline Silicon Gettered by Porous Silicon and Heavy Phosphorous Diffusion

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2004年第2期9卷 242-245页

作者：刘祖明 souleymane K traore 张忠文罗毅 Solar Energy Research Institute Yunnan Provincial Renewable Energy Engineering Key Laboratory Yunnan Normal University Kunming 650092 China Department of Electronic Engineering Tsinghua University Beijing 100084 China

The biggest barrier for photovoltaic (PV) utilization is its high cost, so the key for scale PV utiliza-tion is to further decrease the cost of solar cells. One way to improve the efficiency, and therefore lower the cost, is to increase the minority carrier lifetime by controlling the material defects. The main defects in grain boundaries of polycrystalline silicon gettered by porous silicon and heavy phosphorous diffusion have been studied. The porous silicon was formed on the two surfaces of wafers by chemical etching. Phosphorous was then diffused into the wafers at high temperature (900℃). After the porous silicon and diffusion layers were removed, the minority carrier lifetime was measured by photo-conductor decay. The results show that the lifetime抯 minority carriers are increased greatly after such treatment.

关键词： polycrystalline gettering grain boundaries passivation porous silicon heavy phosphorous diffusion

Study on the Movement of Grain Particles on Bionic Non-smooth Surface in Grain Tanks

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Study on the Movement of Grain Particles on Bionic Non-smoot...

作者： souleymane N’Famoussa traore 江苏大学

学位级别：硕士

联合收割机粮箱的籽粒输运过程中存在粘附堆积的问题,这严重影响联合收割机的作业效率。本文基于离散元法(DEM)模拟联合收割机粮箱卸粮过程中水稻颗粒群的运动,分析了粮箱壁面压力分布变化,研究了谷物颗粒群流动特性;设计搭建了微型粮... 详细信息

联合收割机粮箱的籽粒输运过程中存在粘附堆积的问题,这严重影响联合收割机的作业效率。本文基于离散元法(DEM)模拟联合收割机粮箱卸粮过程中水稻颗粒群的运动,分析了粮箱壁面压力分布变化,研究了谷物颗粒群流动特性;设计搭建了微型粮箱台架,基于台架试验研究了粮箱内表面材质和操作参数下的颗粒流动特性;通过仿真和台架试验研究了不同仿真非光滑表面型式下粮箱卸粮过程中的颗粒运动。这对缓解粮箱籽粒粘附堆积,联合收割机粮箱的设计、制造和改进具有重要意义。基于DEM模拟了水稻籽粒在卸粮过程中的运动,研究了粮箱的压力分布,结果表明不同壁面的压力是不一致的,当粮箱装满颗粒时,与粮箱底部的两个倾斜壁面相比,四个垂直壁面承受的应力较低,而粮箱底部的壁面承受最高压力。以粮箱内表面材质(钢、亚克力、木材、塑料)、粮箱底部倾斜角度、螺旋搅龙转速为变量,通过仿真和台架试验研究了卸粮过程中的籽粒流动特性,研究结果表明水稻籽粒在木质表面的附着力小于在钢材和亚克力表面上的附着力,而在塑料表面的附着力大于其他材料。增加粮箱底部倾斜角度增加了水稻籽粒在表面的附着力,同时提高了螺旋钻的转速,减少了籽粒在粮箱表面的附着力。将两种不同的仿生非光滑表面型式应用于粮箱内表面,并基于仿真和台架试验研究了粮箱卸粮过程中的籽粒粘附和运动变化,结果表明水稻籽粒在非光滑仿生表面粘附的仿真和台架试验结果相似。粘附在仿生1和仿生2表面的籽粒质量均少于光滑表面。比较两种仿生表面样品上水稻籽粒的定性附着力,水稻籽粒在仿生1表面的附着力低于仿生2表面。在这项研究中,粮箱壁面压力分布、粮箱底部倾斜角度、表面材料的数据可用于粮箱制造中的设计。研究表明,仿生非光滑表面可用于谷物处理设备,以减少谷物在潮湿表面上的粘附堆积。

关键词：联合收割机粮箱颗粒运动 DEM 仿生非光滑

BP neural network model for material distribution prediction based on variable amplitude anti-blocking screening DEM simulations

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

International Journal of Agricultural and Biological Engineering 2023年第4期16卷 190-199页

作者： Zheng Ma Yongle Zhu Zhiping Wu souleymane Nfamoussa traore Du Chen Licheng Xing School of Agricultural Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina Key Laboratory of Modern Agricultural Equipment and Technology Ministry of Education&Jiangsu ProvinceJiangsu UniversityZhenjiang 212013JiangsuChina Key Laboratory for Theory and Technology of Intelligent Agricultural Machinery and Equipment Jiangsu UniversityZhenjiang 212013JiangsuChina College of Engineering China Agricultural UniversityBeijing 100083China Jiangsu World Agricultural Machinery Co. Ltd.Picheng Industrial ParkDanyang 212311JiangsuChina

The material feeding changing of combine harvester is easy to cause accumulation and blockage of the vibrating screen,which seriously affects the harvest *** order to alleviate such accumulation and blockages on the vibrating screen surface,the guide chute rotation angle of the improved variable amplitude screening mechanism was selected as the target variable,and EDEM-RecurDyn was employed to simulate the anti-blocking process of the variable amplitude under a changing feeding quantity(0.5 kg/s abnormal,0.2 kg/s normal)of materials(rice grain and stem mixture).A BP(an error back propagation algorithm)neural network was designed and the prediction model of the material distribution was subsequently constructed on the variable screening surface under different chute angles during abnormal *** results revealed a continuous decrease in the quality and time of the material blockage at the front end of the screen surface with the increasing guide chute *** the guide chute angle of 20°-45°and adjustment time of 3-6 s,the blocked and accumulated materials at the front-end screen surface was be moved back to Grid 6 for ***,overtime,the screen surface materials continued to move back under the chute angle of 40°-45°,which had a great impact on the screening *** the guide chute angle of 30°-35°and adjustment time of 4 s,the materials on the screen surface were evenly distributed in Grid *** was able to alleviate the accumulation and blockage of the screen surface *** R of the material distribution prediction model(BP neural network)on the screen surface was determined as 0.97,indicating the high reliability and accuracy of the material distribution model on the screen surface based on the BP neural *** work provides an important reference for the variable amplitude intelligent control of screen surface material anti-blocking.

关键词： variable amplitude material distribution EDEM-RecurDyn BP neural network

Ultrasound of the Siren Syndrome (Sirenomelia) in the District of Bamako Apropos of a Case

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Medical Imaging 2022年第3期12卷 165-170页

作者： Ouncoumba Diarra Ousmane traore Ilias Guindo Mamadou Dembele souleymane traore Alassane Kouma Issa Cisse Mahamadou Diallo Siaka Sidibe Adama Diama Keita Radiology Department of the Reference Health Center of the CIII Commune of Bamako Bamako Mali Radiology Department of the Medical Clinic “Marie Curie” Bamako Mali Radiology Department of the KATI Hospital Center Bamako Mali Radiology Department of the Medical Clinic “FERTILIA-DIAFOUNOU” Bamako Mali Radiology Department of the “Luxembourg” Mother-Child Hospital Center Bamako Mali Radiology Department of the “Gabriel TOURE” Hospital Center Bamako Mali Radiology Department CHU Point G Bamako Mali

Sirenomelia is a rare fetal malformation with more or less complete fusion of both lower limbs consistently associated with bilateral renal abnormalities. The positive diagnosis can be made antenatally by ultrasound during the first trimester of pregnancy but often before the 22 weeks of amenorrhea. The objective was to think about the possible diagnosis by ultrasound in front of the urinary anomalies and the ologiamnios during the morphological study of the second trimester of pregnancy. We report a case of sirenomelia in a 25-year-old lady as part of the routine prenatal assessment suspected and confirmed during the morphological ultrasound of the second trimester of pregnancy and confirmed after the termination of pregnancy in Mali in the Health Center of Reference of commune III of the district of Bamako. The morphological ultrasound made it possible to diagnose the malformation of the urinary tract, the amniotic fluid and to make the therapeutic decision of medical termination of pregnancy at the end of confirming the siren syndrome.

关键词： Sirenomalia Ultrasound Fetal Malformation Mali

Multivariate Statistical Analysis of Dominating Groundwater Mineralization and Hydrochemical Evolution in Gao, Northern Mali

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Earth Science 2024年第5期35卷 1692-1703页

作者： Adiaratou traore Xumei Mao Alhousseyni traore Yahaya Yakubu Aboubacar Modibo Sidibe School of Environmental Studies China University of Geosciences College of Construction Engineering Jilin University

Population growth and expanding urbanization have caused persistent shortages and contamination of groundwater resources in Mali, Africa. The increase in groundwater salinity makes it more difficult for residents to obtain drinking water, it is necessary to clarify the causes and control factors of groundwater mineralization in Gao region, northern Mali. Based on the analysis of the hydrochemical composition of groundwater in 24 boreholes, Piper and Sch?eller diagrams, principal component analysis(PCA) and hierarchical cluster analysis(HCA) are used to carry out multivariate statistical analysis on the main ions. The results show that the groundwater samples are weakly alkaline, with p H values ranging from 5.83 to 8.40, and the average values of boreholes are 7.50, respectively. The average electrical conductivity(EC) value is 354.4(μS/cm), and the extreme value is between 124.0 and 1 247(μS/cm). Water is usually mineralized and presents nine types of water phase. The three principal components explain 84.42% of the total variance for 13 parameters. The factor F1(58.85%), the factor F2(16.88%) and the factor F3(8.69%) present for the majority of the total data set. In addition, multivariate statistical analysis confirmed the genetic relationship among aquifers and identified three main clusters. Clustering related to groundwater mineralization(F1), clustering related to oxide reduction and iron enrichment(F2), and clustering of groundwater pollution caused by nitrate and magnesium(F3). We found that agriculture, weathering activities and dissolution of geological materials promote the mineralization of groundwater. Groundwater quality in the Gao region is becoming less and less potable because of increasing salinity.

关键词： hydrochemical composition multivariate statistical analysis mineralization hydro-chemical evolution Gao northern Mali hydrogeology

Petrology and Structural Characterization of Post-Neoproterozoic Dolerites from the Kimberlite Fields in the Kéniéba Region (Western Mali)

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Open Journal of Geology 2024年第6期14卷 655-670页

作者： Gbele Ouattara Baco traore Ziandjêdé Hervé Siagné Aboubacar Denon souleymane Sangare Marc Ephrem Allialy Laboratoire des Sciences Gographiques du Gnie Civil et des Gosciences Institut National Polytechnique Flix HOUPHOUT-BOIGNY (INP-HB) Yamoussoukro Cte dIvoire EUREKAGEO Sarl Consulting Mining Company Bamako Republic of Mali Unit de Formation et de Recherche des Sciences de la Terre et des Ressources Minires (UFR-STRM) University of Cocody Abidjan Cte dIvoire

Post-Neoproterozoic dolerites from the Kéniéba region (Western Mali) are often associated with kimberlites. The rarity of kimberlite outcrops led to the study of doleritic rocks, spatially associated with them. The petrographic and lithogeochemical study showed that the dolerites of the Kéniéba kimberlitic fields are of tholeiitic nature and of the E-MORB (Enriched-Mid Ocean Ridge Basalt) type. This reflects an enrichment over time, compared to the Birimian dolerites of the volcano-sedimentary greenstone belt of Toumodi, in central C?te d’Ivoire. Furthermore, these dolerites are enriched in SiO2, TiO2, Zr and poor in Fe2O3, MgO. These dolerites would have formed in a late to post-orogenic intracontinental context during the breakup of Gondwana. Structurally, Kéniéba dolerites are often associated with kimberlite pipes, fractures and large deep structures identified using aeromagnetic images. Taking into account the fact that kimberlites do not outcrop in the Kéniéba region, the geochemical study coupled with the interpretation of aeromagnetic data proved to be very useful for the search for pipes.

关键词： Dolerites Kimberlitic Fields Petrology Structures Kéniéba Mali

BP神经网络预测变振幅防堵筛分性能研究——基于EDEM-RecurDyn仿真

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国农机化学报 2022年第11期43卷 75-80页

作者：朱永乐马征陈树人 souleymane Nfamoussa traore 李耀明姜晟江苏大学现代农业装备与技术教育部重点实验室江苏镇江212013 江苏大学农业工程学院江苏镇江212013

针对物料喂入量变化导致振动筛面堆积堵塞,影响筛分性能的问题。以变振幅筛分机构导向滑槽转角为变量,RecurDyn和EDEM联合仿真水稻籽粒、茎秆非正常喂入(0.5 kg/s)条件下变振幅防堵筛分过程。BP神经网络预测不同滑槽转角下变振幅的筛分... 详细信息

针对物料喂入量变化导致振动筛面堆积堵塞,影响筛分性能的问题。以变振幅筛分机构导向滑槽转角为变量,RecurDyn和EDEM联合仿真水稻籽粒、茎秆非正常喂入(0.5 kg/s)条件下变振幅防堵筛分过程。BP神经网络预测不同滑槽转角下变振幅的筛分效率、含杂率,优化变振幅调节,缓解筛面堆积堵塞,改善筛分性能。结果表明物料非正常喂入(0.5 kg/s)下导向滑槽转角0°~10°时筛分效率在55%~58%内平稳上升,含杂率在0.1%~0.16%内小范围波动变化;滑槽转角15°~40°时筛分效率在58%~75%内线性增大,含杂率在0.11%~0.19%内波动上升;滑槽转角40°~45°时筛分效率骤然线性下降至65.8%,含杂率陡然升高至0.37%。BP神经网络预测滑槽转角在37°时变振幅筛分效率最高、含杂率较低,变振幅防堵筛分性能更好,此时筛分效率和含杂率为74.30%、0.20%。BP神经网络预测模型R^(2)为0.999,预测误差集中在-0.00041,预测曲线均高度拟合。验证了BP神经网络预测模型的可靠性和精确度。这为未来变振幅防堵筛分的智能化调控提供了依据。

关键词：变振幅 EDEM-RecurDyn BP神经网络筛分效率含杂率

A Generic and Reliable Land Acquisition Protocol Implementation for Sub-Saharan Africa Countries

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Computer and Communications 2024年第1期12卷 208-245页

作者： Bayomock Linwa André Claude traore Hamidou Department of Computer Science International University of Grand-Bassam Grand-Bassam Ivory Coast

Land acquisition is subject of many frauds worldwide. In Africa countries, land acquisition frauds are a real curse. Main reasons of the high land acquisition frauds in Africa are a lack of a reliable land acquisition protocol implementation, no centralized information system that records land transactions and integrates all actors, lack of education about the acquisition protocol and lack of applied sanctions in case of frauds. As of sanctions, the issue is bound to the corruption plague in Africa. Authorities that are supposed to rule the laws are not well paid and are part of the corruption scheme. Most frequent frauds are multiple sales of the same land, falsified land title, false owner identification. In Africa, a land belongs generally to the first residents of the area. To claim ownership of a land, an owner should be recognized by the rural or city authorities. To achieve this recognition, he must obtain from those authorities an attribution letter. The author proposed a complete and reliable land acquisition protocol named ACLAP (Africa Countries Land Acquisition Protocol). The purpose of this paper is to explain the main components of the protocol implementation and show its efficiency when confronting fraud threats. In this paper, a Generic and Reliable Land Acquisition Protocol Implementation in Sub-Saharan Africa countries context is proposed. The platform keeps relevant land transaction information for administrators, managers, buyers, sellers, or for people consultation purpose. The application may be used in village, city, department, region, or country for land management decision making.

关键词： Land Acquisition Protocol Reliable Africa

The Dual of the Two-Variable Exponent Amalgam Spaces (L^q(),l^p())(Ω)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Applied Mathematics and Physics 2024年第2期12卷 383-431页

作者： Sambourou Massinanke Sékou Coulibaly Mamadou traore Departement d’Etudes et de Recherches de Mathématiques et d’Informatique Université des Sciences des Techniques et des Technolo-gies de Bamako Bamako Mali

Wiener amalgam spaces are a class of function spaces where the function’s local and global behavior can be easily distinguished. These spaces are ex-tensively used in Harmonic analysis that originated in the work of Wiener. In this paper: we first introduce a two-variable exponent amalgam space (Lq(),lp())(Ω). Secondly, we investigate some basic properties of these spaces, and finally, we study their dual.

关键词： Amalgam Spaces Variable Exponent Lebesgue Spaces Dual of a Vector Space