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基于超声无损检测对管道沉积物参数的分析

压电与声光 2018年第4期40卷 543-546页

作者：宗堃张栋臣 CHATI Farid LEON fernand 法国诺曼底勒阿弗尔大学声波与复杂介质国家实验室勒阿弗尔法国76600 青岛科技大学自动化与电子工程学院山东青岛266061

介绍了基于兰姆(Lamb)导向声波的对钢管中非对称沉积物体积参数的分析方法。通过收发分置的超声波换能器构建实验环境,分析散射曲线,获取合适的频率。最后利用该检测声波,使其在多个拥有各类体积参数沉积物的钢管内传播,进而通过换能器... 详细信息

介绍了基于兰姆(Lamb)导向声波的对钢管中非对称沉积物体积参数的分析方法。通过收发分置的超声波换能器构建实验环境,分析散射曲线,获取合适的频率。最后利用该检测声波,使其在多个拥有各类体积参数沉积物的钢管内传播,进而通过换能器得到多组实验数据,并得出输出信号的幅值大小会随着沉积物体积的增加而减少的实验结果。

关键词：兰姆(Lamb)导向声波收发分置叉指换能器聚偏氟乙烯(PVDF) 散射曲线

Mapping of the Water Table Levels of Unconfined Aquifers Using Two Interpolation Methods

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Journal of Geographic Information System 2016年第4期8卷 480-494页

作者： Oswaldo Augusto Filho Wanessa Soares Clemente Iriguay fernandéz Geotechnical Department Engineering School of Sao Carlos University of Sao Paulo Sao Paulo Brazil Department of Civil Engineering University of Granada Granada Spain

The spatial prediction of the water table can be used for many applications related to civil works (foundations, excavations) and other urban and environmental management activities. Deterministic and geostatistical interpolation methods were used to predict the spatial distribution of water table levels (unconfined aquifers) of important geological formations of the Joao Pessoa City (capital of Paraiba State, Brazil) with dense urban occupation and high demand for new civil works. The deterministic (topo to raster) and geostatistical (ordinary kriging) interpolation methods were evaluated using a Geographic Information System (GIS)-based investigation. The water table levels were obtained from 276 boring logs of Standard Penetration Test (SPT) in situ investigation distributed over the geological formations studied (an area of 59.8 km2, covering 40 districts of the Joao Pessoa City). The Nspt values and textural characterization data are stored for levels of 1 m depth. Some boreholes located in the area investigated were not included in the interpolation processes in order to be compared with estimated values (validation of the results). Maps of the water table depths were also produced to further analyze the quality of the water table surfaces interpolated by both methods. The phreatic surface interpolations provided satisfactory results for both methods (RMSE = 1.8 m). The topo to raster method showed a slight general tendency to be less affected by local values in relation to the kriging method and also has the advantage of integrating the drainage flow system, which is a relevant aspect for spatial models of the water table levels of unconfined aquifers. The ordinary kriging (geostatistical method) provides a prediction surface and some measure of the certainty or accuracy of the predictions.

关键词： Water Table Deterministic and Geostatistical Interpolation Methods SPT Boreholes Geological-Geotechnical Database

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基于FPGA的I/O控制器的设计和实现

计算机仿真 2013年第1期30卷 254-258页

作者：怀靓亮 fernand Lone Sang 中航工业雷达与电子设备研究院江苏无锡214063 LAAS-CNRS 法国图卢兹31028

对于计算机信息系统受到攻击基本上可以分为基于CPU和I/O控制器这两种。对于CPU的攻击已经被深入研究,各种成熟的对策也被广泛的应用。但是对于I/O控制器攻击的研究非常缺乏有效的保护机制。为了研究关于I/O控制器的攻击,使用FPGA可编... 详细信息

对于计算机信息系统受到攻击基本上可以分为基于CPU和I/O控制器这两种。对于CPU的攻击已经被深入研究,各种成熟的对策也被广泛的应用。但是对于I/O控制器攻击的研究非常缺乏有效的保护机制。为了研究关于I/O控制器的攻击,使用FPGA可编程技术设计和实现了一款PCI Express总线的平台。平台能产生任意种类的关于PCI Express事务层的信息包,为研究各类I/O控制器的攻击提供了基础。

关键词：信息系统可编程技术攻击

Calcium-Magnesium Ca/Mg Ratios and Their Agronomic Implications for the Optimization of Phosphate Fertilization in Rainfed Rice Farming on Acidic Ferralsol in the Forest Zone of Ivory Coast

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Design and Multicriteria Optimization of a Two-Stage Reactive Extrusion Process for the Synthesis of Thermoplastic Polyurethanes

Open Journal of Soil Science（土壤科学期刊） 2024年第1期

作者： fernand G.Yao Brahima Kone Franck M.L.Bahan Kouadio Amani Jean L.Essehi Mamadou B.Ouattara Konan E.B.Dibi Brou Kouame François Lompo Albert Yao-Kouame

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Engineering（科研） 2012年第9期4卷 497-514页

作者： Sandrine Hoppe Dimitrios Meimaroglou Mauricio Camargo Christian Fonteix fernand Pla Equipe de Recherche des Processus Innovatifs (ENSGSI) Université de Lorraine Nancy France Laboratoire Réactions et Génie des Procédés (CNRS) Université de Lorraine Nancy France Université de Lorraine Nancy France

This paper presents the implementation of two multicriteria optimization methods based on different approaches, namely, Rough Set Method (RSM) and Net Flow Method (NFM), to the manufacture by reactive extrusion of linear thermoplastic polyurethanes (TPUs), appropriate for medical applications. A preliminary study allowed determining the process operating conditions for which the polymerization time and the average residence time of the reactants in the extruder are of the same order of magnitude. Prior to the optimization, a neural network model able to predict with acceptable accuracy the effect of the operating conditions on the output process variables, was constructed and validated. This model was then used to determine, using Pareto’s concept, a set of non-dominated solutions constituting Pareto’s domain. These solutions were then ranked according to the preferences of a decision maker using NFM and RSM. This allowed providing the 10% highest ranked solutions of Pareto’s domain and proposing a set of optimal operating conditions for the production, with the lowest energy consumption, of TPUs with targeted properties and high purity. Experimental validation runs carried out under similar operating conditions gave rise to criteria values confirming the su- perior performance of NFM, without rejecting, at the same time, the values obtained using RSM.

关键词： Reactive Extrusion Thermoplastic Polyurethanes Modelling Multicriteria Optimization Decision-Making Support

Sizing of a Filter (L-C) for a 180°Control Inverter Connected to a Medium Voltage Network

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Open Journal of Applied Sciences 2021年第5期11卷 565-576页

作者： Kouakou fernand Koffi Gondo Yake Raymond Gbegbe Georges Loum Olivier Asseu Institut National Polytechnique Félix Houphouë t Boigny (INP-HB) Yamoussoukro C&#244 te d’Ivoire Université Félix Houphouë t Boigny (UFHB) Abidjan C&#244 te d’Ivoire Ecole Supérieure Africaine des Technologies d’Information et de la Communication (ESATIC) Abidjan C&#244 te d’Ivoire

This paper studies the design and sizing of a filter (L-C) for an inverter with 180° control in Medium voltage (MV), based on formulas of the capacitance of the capacitor C and the inductance L of the filter (L-C) of an SPWM inverter. These formulas were obtained by minimizing two parameters: the reactive power of the capacitor (capped at 5% of the apparent power of the load) and the ripple of the current flowing through inductance L (capped at 10% of the current supplying the load). The application of these formulas for the calculation of the filter (L-C) of the 180° control inverter in MV is not conclusive. Studies have been carried out to make them applicable. The results show that limiting the current ripple in the inductor to 10% of the load current is a valid assumption and that limiting the reactive power of the capacitor to 5% of the apparent power of the load presents shortcomings. The results also show that setting the inductance L of the filter to Lmaxi and the capacitor C from 35 × Cmaxi to 400 × Cmaxi gives voltage and current THDs that meet the 519 IEEE-2014 standards.

关键词： filter (L-C) THD inverter with 180° control and with SPWM control mathematical iterations MV. MATLAB-SIMULINK

Pollination Efficiency of Amegilla calens(Hymenoptera: Apidae) on Gossypium hirsutumL. (Malvaceae) Variety L457 Flowers at Meskine (Maroua, Cameroon)

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Agricultural Sciences 2021年第10期12卷 1150-1167页

作者： Issaya Kodji Issaya Beaudelaine Stephanie Kengni Sidonie Fameni Tope fernand-Nestor Tchuenguem Fohouo Department of Biological Sciences Faculty of Science University of Maroua Maroua Cameroon

Animal pollination is a key of reproduction of more plants species including Gossypium hirsutum. This Malvaceae is the best cultivated oilseed plant in tropical and subtropical regions in the world. This research evaluates the interaction between Amegilla calens and Gossypium hirsutum from 2018 to 2019 based on the activities of the solitary bee on the flowers of this plant and their productive impact in field. The experiment was focused on four repeated treatments during the flowering phase: the first two were characterised by the existence or absence of protection of the flowers regarding all insects and the other two made up of flowers designed for the exclusive visit of A. calens or open then protected again without a visit from an insect or any other organism. Daily rhythm of activity, behavioural ecology, the pollination efficiency, the fruiting rate, the number of seeds per capsule and the percentage of normal seeds were evaluated. Among twenty insects species recorded A. calens is the most abundant with 30.72% of 655 visits and the most efficient pollinator. Amegilla calens is active on G. hirsutum flowers from 6 a.m. to 5 p.m. with a maximum activity situated from 8 a.m. to 9 a.m. All visits of this solitary bee are able to fertilize the flowers of Malvaceae. The mean duration of a visit per flower for pollen harvest is also more important (23.57 ± 0.96 sec) than nectar collection (13.69 ± 0.72 sec). For the two years, through its pollination efficiency, A. calens increased the fruiting rate by 20.30%, as well as the percentage of normal seeds by 32.39%. Therefore, we concluded that A. calens is the important pollinator and increases the fecundity and number of normal seeds of G. hirsutum.

关键词： Amegilla calens Gossypium hirsutum Meskine Pollination Efficiency Yields

Molecular Identification of Co-Existence of Carbapenemase and Extended-Spectrum β-Lactamase Genes in Klebsiella pneumoniaeClinical Isolates, and Their Phylogenetic Patterns in Kenya

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Advances in Microbiology 2021年第8期11卷 399-415页

作者： Noutin fernand Michodigni Atunga Nyacheo Juliah Khayeli Akhwale Gabriel Magoma Andrew Nyerere Kimang’a Department of Molecular Biology & Biotechnology Pan African University Institute for Basic Sciences Technology and Innovation (PAUSTI) Nairobi Kenya Institute of Primate Research (IPR) Nairobi Kenya Jomo Kenyatta University of Agriculture and Technology (JKUAT) Nairobi Kenya

The increasing incidence of multidrug-resistant Klebsiella pneumoniae strains has become a serious global healthcare problem. Additionally, the carriage of both extended-spectrum ß-lactamase and carbapenemase genes on plasmid and genomic DNA in K. pneumoniae clinical isolates has not been documented in Kenya. This study aimed to assess the presence of extended spectrum β-lactamase (ESBL) and carbapenemase genes on genomic and plasmid DNA in K. pneumoniae, and classify these super-bug clinical isolates based on their phylogenetic patterns. The identification of Klebsiella-like clinical isolates (n = 20) collected from Kenyatta National Hospital in Nairobi was performed using API 20E Kit. Screening and confirmation for ESBL and carbapenemase phenotypes were conducted using Kirby-Bauer disk diffusion susceptibility test protocol. Conventional PCR technique was used to characterize ESBL and carbapenemase resistant genes on both genomic and plasmid DNA. Subsequently, 16S rRNA gene amplification and sequencing were performed. The 16S rRNA gene contiguous sequences of the bacterial isolates were analyzed using the ChromasPro. The gene sequence was compared with the sequences in GenBank database, using the BLAST program of NCBI to obtain the nearest phylogenetic neighbours from the databases. Then, the sequences of MDR K. pneumoniae and its relatives were aligned using ClustalW. The evolutionary history was inferred by using the maximum likelihood algorithm in MEGA MX. The phenotypic data of antibiotic susceptibility testing revealed that 2/20 (10%) clinical isolates were resistant both to imipenem and meropenem and producers of carbapenemase. These isolates were carbapenemase producers but not extended β-lactamases. However, 3/20 (15%) isolates that co-harboured blaNDM-1, blaIMP, blaTEM, and bla-OXA were identified during genotypic analysis. The positive control used separately yielded the expected band sizes for blaIMP (275

关键词： MDR Klebsiella pneumoniae Plasmid Genomic DNA Extended Spectrum β-Lactamase Carbapenem 16S rRNA

中学后教育:应对全球化知识经济的政策工具(英文)

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中学后教育:应对全球化知识经济的政策工具(英文)