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A high-power electromagnetic source for disabling improvised explosive devices

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High Voltage 2024年第2期9卷 403-409页

作者： Laurent Ariztia Njomza Ibrahimi Alexey Zhabin Antoine Silvestre de Ferron Marc Rivaletto Edson Martinod valérie Bertrand Bucur Novac Laurent Pécastaing Universite de Pau et des Pays de l’Adour E2S UPPASIAMEPauFrance XLIM UMR CNRS BriveLimogesFrance CISTEME LimogesFrance Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLeicestershireUK

Ultra-wideband(UWB)microwave sources driven by specialised pulsed power generators have experienced a considerable development in the last decade due to their wide domain of new applications such as defence or counter-terrorism *** authors present the main findings of a research dedicated to the development of a pulsed power-driven electromagnetic field source for disabling improvised explosive devices(IED).The pulsed power generator driving the source is a 13-stage compact Marx producing voltage pulses reaching an amplitude of 0.5 MV,with a pulse repetition frequency(PRF)of up to 100 *** generator is coupled to a bipolar pulse forming line,providing bipolar pulses with a dV/dt of around 1.6 MV/*** pulsed power system feeds an array composed of 16 Koshelev-type UWB antennas through an impedance matching *** resulting electromagnetic source is capable to produce pulsed electric fields(PEFs)having a figure-of-merit(FOM)of 1 ***,practical experiments were carried out to study the effects of the PEFs on *** targets used in the present study are M2B type flashbulbs,known to have the same susceptibility as the US army M6 *** configurations of wires(shielded,twisted,etc)with different lengths were used in connecting items inside these *** tests were performed by placing the flashbulbs at different distances to determine the essential parameters(i.e.,amplitude,duration,and frequency range)of the PEFs required to trigger *** overview of the experimental campaign and the main findings are also presented followed by conclusions.

关键词： power bipolar source

A study on wildfire impacts on greenhouse gas emissions and regional air quality in South of Orléans,France

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Journal of Environmental Sciences 2024年第1期135卷 521-533页

作者： Chaoyang Xue Gisèle Krysztofiak Yangang Ren Min Cai Patrick Mercier Frédéric Le Fur Corinne Robin Benoit Grosselin Véronique Daele Max RMcGillen Yujing Mu valéry Catoire Abdelwahid Mellouki Laboratoire de Physique et Chimie de l’Environnement et de l’Espace(LPC2E) CNRS–UniversitéOrléans–CNES(UMR 7328)Orléans Cedex 245071France Institut de Combustion AérothermiqueRéactivitéEnvironnement(ICARE)CNRSOrléans Cedex 245071France Research Centre for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Lig’Air-Association de surveillance de la qualitéde l’air en région Centre-val de Loire Saint-Cyr-en-Val 45590France Mohammed V University RabatMorocco

Wildfire events are increasing globally which may be partly associated with climate change,resulting in significant adverse impacts on local,regional air quality and global *** September 2020,a small wildfire(burned area:36.3 ha)event occurred in Souesmes(Loiret-Cher,Sologne,France),and its plume spread out over 200 km on the following day as observed by the MODIS *** on measurements at a suburban site(~50 km northwest of the fire location)in Orléans and backward trajectory analysis,young wildfire plumes were *** increases in gaseous pollutants(CO,CH_(4),N_(2)O,VOCs,etc.)and particles(including black carbon)were found within the wildfire plumes,leading to a reduced air *** factors,defined as EF(X)=ΔX/ΔCO(where,X represents the target species),of various trace gases and black carbon within the young wildfire plumes were determined accordingly and compared with previous *** in the ambient ions(such as ammonium,sulfate,nitrate,chloride,and nitrite in the particle-and gasphase)and aerosol properties(e.g.,aerosol water content,aerosol p H)were also quantified and ***,we estimated the total carbon and climate-related species(e.g.,CO_(2),CH_(4),N_(2)O,and BC)emissions and compared them with fire emission *** biomass burning emission inventories have uncertainties in estimating small fire burned areas and *** instance,we found that the Global Fire Assimilation System(GFAS)may underestimate emissions(e.g.,CO)of this small wildfire while other inventories(GFED and FINN)showed significant *** that it is the first time to record wildfire plumes in this region,related atmospheric implications are presented and discussed.

关键词： Wildfire Air quality Emission factor Emission inventory VOLTAIRE supersite

Piezoelectric resonant ice protection systems–Part1/2:Prediction of power requirement for de-icing a NACA 0024 leading edge

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Chinese Journal of Aeronautics 2024年第3期37卷 92-103页

作者： valerian PALANQUE Jason POTHIN vale′rie POMMIER-BUDINGER Marc BUDINGER Institut Clement Ader University of ToulouseINSAISAE-SUPAEROMINES ALBIUPSCNRSToulouse 31055France ISAE-SUPAERO University of Toulouse10 Avenue Edouard BelinToulouse 31055France

This paper proposes a numerical method to analyze the ice protection capability and predict the power requirements of a piezoelectric resonant de-icing *** method is based on a coupled electro-mechanical finite element analysis which enables the fast computation of the modes of resonance of interest to de-ice curved surfaces and the estimation of the input voltage and current required for a given configuration(defined by its mode,actuator location,ice deposit,etc.).Eventually,the electric power to be supplied can be also *** method is applied to a NACA 0024 leading edge equipped with piezoelectric ***,two extension modes are analyzed and compared with respect to their efficiency and power ***,tests are carried out in an icing tunnel to verify the effectiveness of the piezoelectric ice protection system and the predictions of the maximal required *** system allows de-icing the leading edge in less than 2 s for a glaze ice deposit.

关键词： Ice protection system Piezoelectric Resonance mode Ice fracture Leading edge de-icing

High-performance eight-channel system with fractal superconducting nanowire single-photon detectors

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Chip 2024年第2期3卷 45-52页

作者： Zifan Hao Kai Zou Yun Meng Jun-Yong Yan Fangyuan Li Yongheng Huo Chao-Yuan Jin Feng Liu Thomas Descamps Adrian Iovan val Zwiller Xiaolong Hu School of Precision Instrument and Optoelectronic Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Optoelectronic Information Science and Technology Ministry of EducationTianjin 300072China State Key Laboratory of Modern Optical Instrumentation College of Information Science and Electronic EngineeringZhejiang UniversityHangzhou 300072China Hefei National Research Center for Physical Sciences at the Microscale and School of Physical Sciences University of Science and Technology of ChinaHefei 230026China Department of Applied Physics Royal Institute of Technology(KTH)SE-10691 StockholmSweden

Superconducting nanowire single-photon detectors(SNSPDs)have become a mainstream photon-counting technology that has been widely applied in various *** far,most multi-channel SNSPD systems,either reported in literature or commercially available,are polarization sensitive,that is,the system detection efficiency(SDE)of each channel is dependent on the state of polarization of the to-be-detected ***,we reported an eight-channel system with fractal SNSPDs working in the wavelength range of 930 to 940 nm,which are all featured with low polarization *** a close-cycled Gifford-McMahon cryocooler system with the base temperature of 2.2 K,we installed and compared the performance of two types of devices:(1)SNSPD,composed of a single,continuous nanowire and(2)superconducting nanowire avalanche photodetector(SNAP),composed of 16 cascaded units of two nanowires electrically connected in *** highest SDE among the eight channels reaches 96+^(4)_(-5%),with the polarization sensitivity of 1.02 and a dark-count rate of 13 counts per *** average SDE for eight channels for all states of polarization is estimated to be 90±5%.It is concluded that both the SNSPDs and the SNAPs can reach saturated,high SDE at the wavelength of interest,and the SNSPDs show lower dark-count(false-count)rates,whereas the SNAPs show better properties in the time *** the adoption of this system,we showcased the measurements of the second-order photon-correlation functions of light emission from a singlephoton source based on a semiconductor quantum dot and from a pulsed *** is believed that this work will provide new choices of systems with single-photon detectors combining the merits of high SDE,low polarization sensitivity,and low noise that can be tailored for different applications.

关键词： Superconducting nanowire single-photon detector Superconducting strip photon detector Fractal Quantum optics Photon correlation

Piezoelectric resonant ice protection systems-Part 2/2:Evaluation of benefits at aircraft level

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Chinese Journal of Aeronautics 2024年第6期37卷 50-63页

作者： valerian PALANQUE Thomas PLANES Pommier-Budinger valERIE Budinger MARC Delbecq SCOTT Institut Clement Ader(ICA) INSAISAE-SUPAEROMINES ALBIUPSCNRSUniversity of Toulouse31400 ToulouseFrance Federation ENAC ISAE-SUPAERO ONERA University of Toulouse31400 ToulouseFrance

Piezoelectric resonant de-icing systems are attracting great *** paper aims to assess the implementation of these systems at the aircraft *** article begins with the model to compute the power requirement of a piezoelectric resonant de-icing system sized from the prototype detailed in Part 1/2 of this *** the mass,drag,and fuel consumption of this system and the subcomponents needed for its implementation are *** features of a piezoelectric resonant de-icing system are finally computed for aircraft similar to Airbus A320 aircraft and aircraft of different categories(Boeing 787,ATR 72 and TBM 900)and compared with the existing thermal and mechanical ice protection systems.A sensitivity analysis of the main key sizing parameters of the piezoelectric de-icing system is also performed to identify the main axes of improvement for this *** study shows the potential of such ice protection *** particular,for the realistic input parameters chosen in this work,the electro-mechanical solution can provide a 54% reduction in terms of mass and a 92% reduction in terms of power consumption for an A320 aircraft architecture,leading to a 74% decrease in the associated fuel consumption compared to the actual air bleed system.

关键词： Ice protection system De-icing Piezoelectric Electro-mechanical system Power Fuel consumption

Contribution of SAR Radar Imagery in the Detection of Suspicious Vessels in the Ivorian EEZ

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World Journal of Engineering and Technology 2024年第1期12卷 200-212页

作者： Koffi Cyprien Yoboue Jean-Baptiste Kassi Eric valère Djagoua Tiemelé Jacque-André Laboratory of Remote Sensing and GIS University Center for Research and Application in Remote Sensing (CURAT) Félix Houphouet-Boigny University of Abidjan Cocody Ivory Coast

The present work proposed a method for match SAR and AIS data to detect vessels carrying out suspicious activity in the Ivorian EEZ. Two superposition methods, detected AIS and SAR data, based on point-to-point association on the one hand and point-to-line on the other hand, were used to detect suspicious vessels in Ivorian marine waters. The results showed that most vessels detected in the Ivorian EEZ do not declare their positions to avoid being spotted. These funds are likely to practice illegal, undeclared and unregulated fishing (INN fishing). This clandestine activity is very recurrent in Ivorian waters. This is illustrated by the number of suspicious vessels detected by SAR radar imagery which is greater compared to declared or authorized vessels.

关键词： INN Fishing CFAR Algorithm AIS Sentinel-1A Ivory Coast

Study of Rice Husks and Expanded Polystyrene Composites for Construction Applications

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Open Journal of Civil Engineering 2024年第3期14卷 456-468页

作者： Edem Chabi valéry Kouandété Doko Sena Peace Hounkpè Paul Damien Amadji Emmanuel Olodo Laboratory of Rural Engineering School of Rural Engineering National University of Agriculture Ketou Benin Laboratory of Applied Energy and Mechanics (LEMA) Polytechnic School of Abomey-Calavi University of Abomey-Calavi Abomey-Calavi Benin Department of Civil Engineering Higher National School of Public Works (ENSTP) National University of Sciences Technologies Engineering and Mathematics Abomey Benin

In the current context of environmental challenges, this study focuses on developing innovative and eco-friendly composites using rice husk and recycled expanded polystyrene. This dual-responsibility approach valorizes a by-product like rice husk, often considered waste, and reuses polystyrene, a plastic waste, thereby contributing to CO2 emission reduction and effective waste management. The manufacturing process involves dissolving recycled polystyrene into a solvent to create a binder, which is then mixed with rice husk and cold-compacted into composite materials. The study examines the impact of two particle sizes (fine and coarse) and different proportions of recycled polystyrene binder. The results show significant variations in the mechanical characteristics of the composites, with Modulus of Rupture (MOR) values varying from 2.41 to 3.47 MPa, Modulus of Elasticity (MOE) ranging from 223.41 to 1497.2 MPa, and Stiffness Coefficient (K) from 5.04 to 33.96 N/mm. These characteristics demonstrate that these composites are appropriate for various construction applications, including interior decoration, panel claddings, and potentially for furniture and door manufacturing when combined with appropriate coatings. This study not only highlights the recycling of agricultural and plastic waste but also provides a localized approach to addressing global climate change challenges through the adoption of sustainable building materials.

关键词： Rice Husk Recycled Expanded Polystyrene Eco-Friendly Composites Waste valorization Sustainable Construction

Performance Evaluation of Novel Eco-Materials Composed of Millet Husks, Rice Husks, and Polystyrene

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Open Journal of Composite Materials 2024年第1期14卷 33-43页

作者： Paul Damien Amadji Edem Chabi valéry Kouandété Doko Céphas Houndedji Emmanuel Olodo Laboratory of Applied Energy and Mechanics (LEMA) Polytechnic School of Abomey-Calavi University of Abomey-Calavi Abomey-Calavi Benin Laboratory of Rural Engineering School of Rural Engineering National University of Agriculture Kétou Benin

Managing agricultural waste and expanded polystyrene (EPS) poses significant environmental and economic challenges. This study aims to create composites from millet husks, rice husks, and recycled EPS, using a manufacturing method that involves dissolving the polystyrene in a solvent followed by cold pressing. Various particle sizes and two binder dosages were investigated to assess their influence on the physico-mechanical properties of the composites. The mechanical properties obtained range from 2.54 to 4.47 MPa for the Modulus of Rupture (MOR) and from 686 to 1400 MPa for the Modulus of Elasticity in Bending (MOE). The results indicate that these composites have potential for applications in the construction sector, particularly for wood structures and interior decoration. Moreover, surface treatments could enhance their durability and mechanical properties. This research contributes to the valorization of agricultural and plastic waste as eco-friendly and economical construction materials.

关键词： Bio-Based Composites Millet Husk Rice Husk Expanded Polystyrene Waste valorization Sustainable Construction

Development and Characterization of Particle Boards Based on Sorghum Husk

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Open Journal of Applied Sciences 2024年第9期14卷 2460-2470页

作者： Hamed Tidjani Tabe Gbian Edem Chabi valéry Kouandété Doko Kora Farid Carlos Yarou Emmanuel Olodo Laboratory of Applied Energy and Mechanics (LEMA) Polytechnic School of Abomey-Calavi University of Abomey-Calavi Abomey-Calavi Benin Laboratory of Rural Engineering School of Rural Engineering National University of Agriculture Ketou Benin

This study tackles current environmental challenges by developing innovative and eco-friendly particle boards utilizing sorghum husk, combined with recycled expanded polystyrene (EPS). This dual eco-responsible approach valorizes sorghum husk, often deemed agricultural waste, and repurposes EPS, a plastic waste, thus contributing to CO2 emission reduction and effective waste management. The manufacturing process involves dissolving recycled polystyrene within a solvent to create a binder, which is then mixed with sorghum husk and cold-pressed into composite boards. The study explores the impact of two particle sizes (fine and coarse) and two different concentrations of the recycled EPS binder. Results demonstrate significant variations in the boards’ mechanical properties, displaying a range of Modulus of Rupture (MOR) from 0.84 MPa to 3.85 MPa, and Modulus of Elasticity (MOE) spanning from 658.13 MPa to 1313.25 MPa, influenced by the binder concentration and particle size. These characteristics suggest that the boards can be effectively used in various construction applications, including interior decoration, false ceilings, and potentially for furniture and door manufacturing when combined with appropriate coatings. This study not only exemplifies the valorization of plastic and agricultural wastes but also offers a practical, localized solution to global climate change challenges by promoting sustainable construction materials.

关键词： Eco-Material Bio-Sourced Material Sorghum Husk Particle Board Recycled Expanded Polystyrene Sustainable Construction