Recently,lithium–sulfur(LiS)batteriesachieveincredibleresearchinterestowingtooutstandingtheoreticalstoragecapacity,abundantresources,economical,andecologicalaffability.Nonetheless,therealusageofLSbatteryobstructsbyshuttling-effectofsolublelithium-basedpolysulfides(LiPSs)thatresultinlanguidredoxreactions,whilethevitaldiffusionandmigrationmechanismofLiandSontoTiNsurfaceisyetamyth.Herein,rationalsynthesisoftitaniumnitride(TiN)nanoparticlesandsulfurcomposite(TiN-NPs@S)viadryfreezingmethodascathodematerialisexploredforhighefficiencyLiSbatteries.Theultra-smallnanoparticlesexhibitshighsurfaceareawithnarrowporeswhichserveasconductivechannelsforproficientpassageforions/electronsexchangeduringelectrochemicalenergystoragereactions.Thedensityfunctionaltheory(DFT)computationalresults,chargedensitydistributionandchargetransferandanalysisofgeometryconstructionsindicateTiNsurfacepossessstrongeradsorptionstrengthtoSatomthanLiatomimpliesTiNaspolysulfideadsorbent.TheTiNcathodeafter100cyclesexhibitsanexcellentinitialcapacityof1279?mAh?g?1at0.5?Cabout75.8%oftheoreticalcapacity(1562?mAh?g?1).Thehot-to-cold-synthesismethodprojectsformationofultra-smallsizednanoparticleswhichilluminatesbrightpanoramaforLi–Sbatteriestoachieveexcellentconductivity,highpowerdensityandenergydensity,whichisofgreatadvantageousforindustrialapplications.
Sorting of paper into compatible grades is a necessary step prior to recycling. Current method of manually sorting is tedious, slow, and expensive. Hence, significant part of the waste paper stream is sent to the landfill. High speed automation of the sorting process will improve the cost efficiency and increase the amount of paper recycled significantly. There have been recent developments in automation of this process. Mechanisms for the distribution of the papers from a bale onto a moving conveyor and the pneumatic actuation to deflect papers into different streams are well established. Correct identification of the sample in real-time before the sample reaches the actuation station still remains a challenge since different types of paper and board samples are mixed in a waste stream, and has a lot of variation in terms of color, chemical composition, coating, and prints in black and white and color to different degrees. This is primarily due to the lack of satisfactory sensors and sensor fusion algorithms for sample identification in real-time. In this report, we identify key parameters that must be measured (lignin, stiffness, color gloss), sensor design, and integration of the output from sensors to interpret the type of sample using a fuzzy inference system. Results show that the sensor system proposed is capable of identifying the samples at 90 % accuracy. The sensor system can be integrated onto a conveyor and actuation system for automated sorting.
AmorphousGeOx-coatedreducedgrapheneoxide(rGO)ballswithsandwichstructurearepreparedviaaspray-pyrolysisprocessusingpolystyrene(PS)nanobeadsassacrificialtemplates.Thissandwichstructureisformedbyuniformlycoatingtheexteriorandinterioroffew-layerrGOwithamorphousGeOxlayers.X-rayphotoelectronspectroscopyanalysisrevealsaGe:Ostoichiometryratioof1:1.7.TheamorphousGeOx-coatedrGOballswithsandwichstructurehavelowcharge-transferresistanceandfastLi+-iondiffusionrate.Forexample,atacurrentdensityof2Ag鈥?,theGeOx-coatedrGOballswithsandwichandfilledstructuresandthecommercialGeO2powdersexhibitinitialchargecapacitiesof795,651,and634mAhg鈥?,respectively;thecorresponding700th-cyclechargecapacitiesare758,579,and361mAhg鈥?.Inaddition,atacurrentdensityof5Ag鈥?,therGOballswithsandwichstructurehavea1600th-cyclereversiblechargecapacityof629mAhg鈥?andacorrespondingcapacityretentionof90.7%,asmeasuredfromthemaximumreversiblecapacityatthe100thcycle.
Aiming at the problem that the electromechanical actuator system needs to track the target without error within a finite time, fuzzy sliding mode control has been studied. Aiming at the problems of conventional fuzzy sliding mode control, such as: low precision, low dynamic quality of system, obvious chattering phenomenon and so on, the disturbance observer is introduced to estimate the uncertainty of electromechanical actuator and combine it with conventional fuzzy sliding mode control, then a fuzzy sliding mode control method based on disturbance observer is proposed. Firstly, we build the model of the sliding mode control system of the electromechanical actuator, then design the controller and verify the stability of the system. Finally, we carried out some experiments by MATLAB& Simulink, the results indicate that the fuzzy sliding mode controller based on disturbance observer can decrease the tracking error and the response time, movement accuracy and the resistance to disturbance of the system can be improved, the system has a good performance in tracking, which has a great value to the control of electromechanical actuator.
Immediately after a natural disaster, several assistance activities are required in the affected areas. The challenges faced in this response phase are numerous, due to the limited availability of resources and the lack of centralized coordination, infrastructure and personnel. In this context, this paper aims to present a procedure for the decision-making process of structuring an aid distribution network in disaster response operations with the application of UAV technologies and geographic information systems (GIS). The procedure is applied to a real-life situations event, taking as basis the characteristics of the post-disaster in the municipality of Duque de Caxias in the state of Rio de Janeiro, Brazil, in 2013. Results from the proposed procedure should subsidize the response teams in the design of the distribution network, considering the assessment of the local situation, facility location, vehicle routing and distribution of information in real time.
This paper presents a proposed design of small unmanned aircraft system (SUAS) for reaching a transonic max velocity using micro gas turbine available today. Project Boom is a group of distributed students working on the problem of small scale supersonic flight. The present paper takes aerodynamics, structures, propulsion, stability and control, avionics, and integration design complications into consideration and discusses implications of high speed effects on design decisions. Engine design software, VSPaero, CFD, CAD, structural analysis,3D printing, and engine stand tests are utilized to reach the aircraft design proposed.
We measure the scaling properties of the probability distribution of the smoothed density field in $N$-body simulations of expanding universes with scale-free initial power-spectra, with particular attention to the predictions of the stable clustering hypothesis. We concentrate our analysis on the ratios $S_Q(\ell)\equiv {\bar \xi}_Q/{\bar \xi}_2^{Q-1}$, $Q \leq 5$, where ${\bar \xi}_Q$ is the averaged $Q$-body correlation function over a cell of radius $\ell$. The behavior of the higher order correlations is studied through that of the void probability distribution function.
As functions of ${\bar \xi}_2$, the quantities $S_Q$, $3 \leq Q \leq 5$, exhibit two plateaus separated by a smooth transition around ${\bar \xi}_2 \sim 1$. In the weakly nonlinear regime, ${\bar \xi}_2 \la 1$, the results are in reasonable agreement with the predictions of perturbation theory. In the nonlinear regime, ${\bar \xi}_2 1$, the function $S_Q({\bar \xi}_2)$ is larger than in the weakly nonlinear regime, and increasingly so with $-n$. It is well-fitted by the expression $S_Q= ({\bar \xi}_2/100)^{0.045(Q-2)}\ {\widetilde S}_Q$ for all $n$. This weak dependence on scale proves {\em a small, but significant departure from the stable clustering predictions} at least for $n=0$ and $n=+1$. The analysis of $P_0$ confirms that the expected scale-invariance of the functions $S_Q$ is not exactly attained in the part of the nonlinear regime we probe, except possibly for $n=-2$ and marginally for $n=-1$. In these two cases, our measurements are not accurate enough to be discriminant.
Lithiummetalisconsideredasapotentialanodeforlithiumbatteries,butitscommercializationprocessishinderedbyseveralproblems,includinguncontrollablelithiumdendritegrowth,largevolumeexpansion,lowutilizationoflithiumandsoon.Toaddresstheseissues,inthiswork,lithiophilicsilverlayerswith80?nmthicknessarecoatedonthecommercialcarboncloth(CC)usingthermalevaporationmethodtoregulateLigrowthduringlithiumplatingprocess.Wefindthattheuniformlydistributedsilverlayerscansuccessfullyreducelithiumnucleationover-potential,thusinducingthehomogeneousdepositionofmetalLi,supportedbydensityfunctionaltheorycalculation.Benefitedfromtheas-preparedlithiophilicAglayers,theCC/Ag/Lianodewithanultrahigharealcapacityof16mAhcm?2isachievedadoptingelectrochemicaldepositionat0.2?mA?cm?2withouttheformationoflithiumdendrites,whichisconfirmedbycontinuousdetectionusingvisualdiscriminationandscanningelectronmicroscopeobservation.Asaresult,astabledendrite-freeCC/Ag/Lianodeexhibitsexcellentelectrochemicalproperties:(1)theassembledCC/Ag/Lisymmetricalcellmaintainsastablevoltagehysteresiswithin25?mVaftercycling750?hatacurrentdensityof1?mA?cm?2;(2)TheassembledCC/Ag/Li-LiFePO4cellalsodemonstratesenhancedelectrochemicalbehaviorsintermsofrateperformanceandcapacityretention;(3)Whencoupledwithacarbon/sulfurcathode,theCC/Ag/Lianodealsodemonstratesexcellentcompatibility.TheinitialdischargecapacityoftheCC/Ag/Li-Scellis899.3mAhg?1at0.2C,thereversiblecapacityretainsavalueof587.7mAhg?1after400?cycles,correspondingtoacapacityattenuationrateof0.075%percycle."
This paper investigates the use of unmanned aerial vehicles (UAVs)/drones for providing high data rates to mobile relays (MRs) placed on top of high speed train wagons, thus introducing the concept of Travel Hopping Enabled Resource Allocation (THEResA). The objective is to provide high data rate connectivity to train passengers in 5G+/6G networks. With the drone flying at the same train speed, highly directive beams can be formed and steered between the drone and each of the MRs. The simulation results in the paper show that this leads to high data rate connectivity, which will be reflected in the indoor links between the MRs and the train passengers inside the wagons. The drones maintain the connectivity to the cellular infrastructure by using high speed links with the cellular base stations (BSs) deployed along the rail track, e.g., through free space optics (FSO). The drones use the BS sites for recharging and resuming their operation. Therefore, a separate set of drones, or the same drones when they are not flying over trains, can be used to provide connectivity to remote rural areas. In fact, high speed trains might travel through rural areas with low population density. Although it is practical to lay fiber optic cables along the rail track, villages and small rural population agglomerations far from the railroad might not have access to the internet backhaul. UAVs can provide this connectivity in a delay tolerant fashion, by heading from the BSs/train station sites towards remote areas, collecting/transferring data from/to these areas, then returning to the sites along the rail track to recharge their batteries. This paper presents an analysis that shows the feasibility of this approach.
Accurateinformationonbatterystate-of-charge,expectedbatterylifetime,andexpectedbatterycyclelifeisessentialformanypracticalapplications.Inthispaper,wedevelopanonchemicallybasedpartiallylinearized(inbatterypower)input-outputbatterymodel,initiallydevelopedforlead-acidbatteriesinahybridelectricvehicle.Weshowthatwithproperlytunedparametervalues,themodelcanbeextendedtodifferentbatterytypes,suchaslithium-ion,nickel-metalhydride,andalkaline.Thevalidationresultsofthemodelagainstmeasureddataintermsofpowerandefficiencyatdifferenttemperaturesarethenpresented.Themodelisincorporatedwiththerecoveryeffectforaccuratelifetimeestimation.TheobtainedlifetimeestimationresultsusingtheproposedmodelaresimilartotheonespredictedbytheRakhmatovandVirudhulabatterymodelonagivensetoftypicalloadsatroomtemperature.Apossibleincorporationofthecyclingeffect,whichdeterminesthebatterycyclelife,intermsofthemaximumavailableenergyapproximatedatcharge/dischargenominalpowerlevelisalsosuggested.Theusageoftheproposedmodeliscomputationallyinexpensive,henceimplementableinmanyapplications,suchaslow-powersystemdesign,real-timeenergymanagementindistributedsensornetwork,etc.
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