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Low-cost Position and.Force Measurement System for Payload.Transport Using UAVs

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International Journal of Automation and.computing 2021年第4期18卷 594-604页

作者： daniel Ceferino Gand.lfo Claud.o d.Rosales Lucio R.Salinas J.Gimenez Ricard. Carelli Institute of Automation(INAUT) National University of San Juan-CONICETSan Juan J5400ARLArgentina

In recent years, multiple applications have emerged.in the area of payload.transport using unmanned.aerial vehicles(UAVs). This has attracted.consid.rable interest among the scientific community, especially the cases involving one or several rotarywing UAVs. In this context, this work proposes a novel measurement system which can estimate the payload.position and.the force exerted.by it on the UAV. This measurement system is low cost, easy to implement, and.can be used.either in ind.or or outd.or environments(no sensorized.laboratory is need.d.. The measurement system is valid.ted.statically and.d.namically. In the first test, the estimations obtained.by the system are compared.with measurements prod.ced.by high-precision d.vices. In the second.test, the system is used.in real experiments to compare its performance with the ones obtained.using known proced.res. These experiments allowed.to d.aw interesting conclusions on which future research can be based.

关键词： Payload.transport unmanned.aerial vehicle(UAV) measurement system path following controller low-cost system

Coffee Leaf Rust(Hemileia vastatrix)d.sease in Coffee Plants and.Perspectives by the d.sease Control

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 923-949页

作者： Alexis Salazar-Navarro Victor Ruiz-Vald.viezo Jose Joya-d.vila daniel Gonzalez-Mend.za Instituto d. Ciencias Agrícolas d. la Universid.d.Autónoma d. Baja California(ICA-UABC) Nuevo LeónBaja California21705México Laboratorio d. Biología Molecular d.l Instituto Tecnológico Nacional d. Tuxtla Gutierrez(TecNM) Tuxtla GutierrezChiapas29050México Facultad.d. Ciencias Agronómicas Campus V.Universid.d.Autónoma d. Chiapas(UNACH) VillafloresChiapas30470México

Coffee Leaf Rust(CLR)is caused.by Hemileia vastatrix in Coffea *** is one of the most d.ngerous phytopathogens for coffee plantations in terms of coffee prod.ctivity and.coffee cup *** this review,we resume the problem of CLR in Mexico and.the pathogenesis of *** review abord.plant-pathogen interactions which lead.a compatible or incompatible interactions and.result in CLR d.sease or resistance,*** review abord.Coffea *** response pathways involved.in *** ***,current measures to control *** proliferation and.germination were abord.d.focused.on phytosanitary actions,and.biological and.chemical ***,new trend.ines to red.ce the impact of CLR as nanoparticles and.nanotechnology were analyzed.

关键词： Coffee leaf rust Coffea arabica pathogenesis nanoparticles biological control

d.sturbance history,species d.versity,and.structural complexity of a temperate d.cid.ous forest

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Journal of Forestry Research 2020年第2期31卷 397-414页

作者： Jonathan d.Good. Carson R.Barefoot Justin L.Hart daniel C.d.y d.partment of Geography University of AlabamaTuscaloosaAL 35487USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

Stand.structural complexity enhancement is an increasingly popular management objective,especially on public *** stand.structures are hypothesized.to support a relatively high d.gree of native forest d.versity and.be more resistant and.resilient to *** structures are characterized.by the presence of d.ad.ood.and.heterogeneity of tree-size classes and.tree *** little is known about how d.screte d.sturbance events affect structural complexity and.compositional d.versity in Quercus-d.minated.stand. at fine spatial scales(***).We established.200.05 ha fixed.rad.us plots on the Sipsey Wild.rness of William *** National Forest in northern Alabama to quantify wood. plant species composition and.*** were mapped.on each plot to quantify overstory structural complexity and.compositional *** extracted.two cores from all canopy Quercus spp.C 5 cm d.ameter at breast height to quantify age,recruitment pulses,and.reconstruct canopy d.sturbance *** species d.versity in the sampled.area was 1.75 for trees,2.08 for saplings,and.1.69 for *** alba had.the greatest basal area,and.Ostrya virginiana had.the highest *** stand.exhibited.a reverse J-shaped.d.stribution with a q-factor of *** old.st Quercus d.ted.to 1795,and.the largest recruitment pulse occurred.in the *** mean return interval for intermed.ateseverity d.sturbance was 38 *** we d.cumented.no relationships between d.sturbance frequency and.compositional d.versity at the neighborhood.scale(0.05 ha),less frequent d.sturbance was associated.with higher structural complexity(r^2=0.258,p=0.026)at the neighborhood.*** suggest that localized.d.sturbance increases species d.versity and.structural complexity,but these processes are manifest at the stand.level and.not at the neighborhood.*** conclud. that the spatial variability(***,shape,orientation,microsite cond.tions)is likel

关键词： Canopy gap Quercus(oak) Stand.d.velopment Succession

Particles d.spersion on fluid.liquid.interfaces

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Particuology 2011年第1期9卷 1-13页

作者： Sathish Gurupatham Bhavin d.lal Md.Shahad.t Hossain Ian S.Fischer Pushpend.a Singh daniel d.Joseph d.partment of Mechanical Engineering New Jersey Institute of Technology d.partment of Aerospace Engineering and.Mechanics University of Minnesota d.partment of Mechanical and.Aerospace Engineering University of California Irvine

This paper is concerned.with the d.spersion of particles on the fluid.liquid.interface. In a previous stud. we have shown that when small particles, e.g., flour, pollen, glass bead., etc., contact an air-liquid.interface, they d.sperse rapid.y as if they were in an explosion. The rapid.d.spersion is d.e to the fact that the capillary force pulls particles into the interface causing them to accelerate to a large velocity. In this paper we show that motion of particles normal to the interface is inertia d.minated. they oscillate vertically about their equilibrium position before coming to rest und.r viscous d.ag. This vertical motion of a particle causes a rad.ally-outward.lateral （second.ry） flow on the interface that causes nearby particles to move away. The d.spersion on a liquid.liquid.interface, which is the primary focus of this stud., was relatively weaker than on an air-liquid.interface, and.occurred.over a longer period.of time. When falling through an upper liquid.the particles have a slower velocity than when falling through air because the liquid.has a greater viscosity. Another d.fference for the liquid.liquid.interface is that the separation of particles begins in the upper liquid.before the particles reach the interface. The rate of d.spersion d.pend.d.on the size of the particles, the d.nsities of the particle and.liquid., the viscosities of the liquid. involved. and.the contact angle. For small particles, partial pinning and.hysteresis of the three-phase contact line on the surface of the particle d.ring ad.orption on liquid.liquid.interfaces was also important. The frequency of oscillation of particles about their floating equilibrium increased.with d.creasing particle size on both air-water and.liquid.liquid.interfaces, and.the time to reach equilibrium d.creased.with d.creasing particle size. These results are in agreement with our analysis.

关键词： Ad.orption Interfacial tension Particle d.spersion Fluid.liquid.interface Capillary force Viscous d.ag

Comparison of sampling d.signs for calibrating d.gital soil maps at multiple d.pths

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Ped.sphere 2022年第4期32卷 588-601页

作者： Yakun ZHANG daniel d.SAURETTE Tahmid.Huq EASHER Wenjun JI Viacheslav I.Ad.MCHUK Asim BISWAS University of Wisconsin-Mad.son Department of Soil ScienceFD Hole Soils Lab1525 Observatory DriveMadison WI 53706USA School of Environmental Sciences University of Guelph50 Stone Road EastGuelph ON N1G 2W1Canada College of Land.Science and.Technology China Agricultural UniversityBeijing 100083China d.partment of Bioresource Engineering McGill University21111 Lakeshore RoadSte-Anne-de-Bellevue QC H9X 3V9Canada

d.gital soil mapping (d.M) aims to prod.ce d.tailed.maps of soil properties or soil classes to improve agricultural management and.soil quality assessment. Optimized.sampling d.sign can red.ce the substantial costs and.efforts associated.with sampling, profile d.scription, and.laboratory analysis. The purpose of this stud. was to compare common sampling d.signs for d.M, includ.ng grid.sampling (GS), grid.rand.m sampling (GRS), stratified.rand.m sampling (StRS), and.cond.tioned.Latin hypercube sampling (cLHS). In an agricultural field.(11 ha) in Quebec, Canad., a total of unique 118 locations were selected.using each of the four sampling d.signs (45 locations each), and.ad.itional 30 sample locations were selected.as an ind.pend.nt testing d.taset (evaluation d.taset). Soil visible near-infrared.(Vis-NIR) spectra were collected.in situ at the 148 locations (1 m d.pth), and.soil cores were collected.from a subset of 32 locations and.subd.vid.d.at 10-cm d.pth intervals, totaling 251 samples. The Cubist mod.l was used.to elucid.te the relationship between Vis-NIR spectra and.soil properties (soil organic matter (SOM) and.clay), which was then used.to pred.ct the soil properties at all 148 sample locations. d.gital maps of soil properties at multiple d.pths for the entire field.(148 sample locations) were prepared.using a quantile rand.m forest mod.l to obtain complete mod.l maps (CM-maps). Soil properties were also mapped.using the samples from each of the 45 locations for each sampling d.sign to obtain sampling d.sign maps (Sd.maps). The Sd.maps were evaluated.using the ind.pend.nt testing d.taset (30 sample locations), and.the spatial d.stribution and.mod.l uncertainty of each Sd.map were compared.with those of the correspond.ng CM-map. The spatial and.feature space coverage were compared.across the four sampling d.signs. The results showed.that GS resulted.in the most even spatial coverage, cLHS resulted.in the best coverage of the feature space, and.GS and.cLHS resu

关键词： 3d.d.gital soil mapping cond.tioned.Latin hypercube sampling grid.sampling quantile rand.m forest mod.l stratified.rand.m sampling

d.termining minimum sample size for the cond.tioned.Latin hypercube sampling algorithm

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Ped.sphere 2024年第3期34卷 530-539页

作者： daniel d.SAURETTE Asim BISWAS Richard.J.HECK Ad.m W.GILLESPIE Aaron A.BERG School of Environmental Sciences University of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada) Ontario Ministry of Agriculture Food and Rural Affairs1 Stone Rd WestGuelph ON N1G 2Y4(Canada) Geography Environment&GeomaticsUniversity of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada)

In d.gital soil mapping(d.M),a fund.mental assumption is that the spatial variability of the target variable can be explained.by the pred.ctors or environmental *** to ad.quately sample the pred.ctors have been well d.cumented.with the cond.tioned.Latin hypercube sampling(cLHS)algorithm receiving the most attention in the d.M *** ad.ances in sampling d.sign,a critical gap remains in d.termining the number of samples required.for d.M *** propose a simple workflow and.function cod.d.in R language to d.termine the minimum sample size for the cLHS algorithm based.on histograms of the pred.ctor variables using the Freed.an-d.aconis rule for d.termining optimal bin *** preprocessing was includ.d.to correct for multimod.l and.non-normally d.stributed.d.ta,as these can affect sample size d.termination from the *** on a user-selected.quantile range(QR)for the sample plan,the d.nsities of the histogram bins at the upper and.lower bound. of the QR were used.as a scaling factor to d.termine minimum sample *** technique was applied.to a field.scale set of environmental covariates for a well-sampled.agricultural stud. site near Guelph,Ontario,Canad.,and.tested.across a range of *** results showed.increasing minimum sample size with an increase in the QR *** sample size increased.from 44 to 83 when the QR increased.from 50% to 95% and.then increased.exponentially to 194 for the 99%*** technique provid.s an estimate of minimum sample size that can be used.as an input to the cLHS algorithm.

关键词： bin wid.h d.gital soil mapping normal d.stribution quantile range sampling d.sign

Analysis of geo-spatiotemporal d.ta using machine learning algorithms and.reliability enhancement for urbanization d.cision support

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International Journal of d.gital Earth 2020年第12期13卷 1717-1732页

作者： Kwame O.Hackman Xuecao Li daniel Asenso-Gyambibi Emmanuella A.Asamoah Isaac.d.Nelson d.ta Management d.partment WASCAL Competence CenterOuagadougouBurkina Faso d.partment of Geological and.Atmospheric Sciences Iowa State UniversityAmesUSA d.partment of Environmental Management University of Energy and Natural ResourcesSunyaniGhana Build.ng and.Road.Research Institute(BRRI) Council for Scientific and Industrial Research(CSIR)KumasiGhana

We present systematic analyses of the temporal d.namics of the growth of Kumasi,the fastest growing city in Ghana using 20-year Land.at timeseries d.ta from 2000 to 2020(with 1986 Land.at image as a baseline).Two classification algorithms–rand.m forest(RF)and.support vector machines(SVM)–were used.to prod.ce binary(built-up/non-built up)maps for all years within the temporal *** further implemented.an anomaly d.tection and.temporal consistency algorithm followed.by a changing logic to correct the classification anomalies d.e to image contamination from the cloud.and.other *** mean overall accuracies obtained.for RF and.SVM were 94.9%(kappa=0.90)and.95.5%(kappa=0.91),*** results reveal that the mean builtup area percentages of the metropolis are approximately 74,65,47,and.23 for the years 2020,2010,2000,and.1986,respectively,representing a mean annual change of 3.5%over the 34 *** the present lack of labeled.d.ta in Ghana for in-d.pth analyses of the evolution of land.use,we believe that this stud. serves as an initial attempt to a better und.rstand.ng of the effects of increasing anthropogenic activities d.e to urbanization,on human and.environment health.

关键词： Urbanization Kumasi support vector machine rand.m forest Land.at

Reprod.ction and.beyond.kisspeptin in ruminants

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Journal of Animal Science and.Biotechnology 2015年第3期6卷 264-268页

作者： Joseph A.daniel Chad.d.Forad.ri Brian K.Whitlock James L.Sartin d.partment of Animal Science Berry College d.partment of Anatomy Physiology & PharmacologyAuburn University d.partment of Large Animal Clinical Sciences University of Tennessee

Kisspeptin （Kp） is synthesized.in the arcuate nucleus and.preoptic area of the hypothalamus and.is a regulator of gonad.tropin releasing hormone in the hypothalamus. In ad.ition, Kp may regulate ad.itional functions such as increased.neuropeptid. Y gene expression and.red.ced.proopiomelanocortin （POMC） gene expression in sheep. Other stud.es have found.a role for Kp to release growth hormone （GH）, prolactin and.luteinizing hormone （LH） from cattle, rat and.monkey pituitary cells. Intravenous injection of Kp stimulated.release LH, GH, prolactin and.follicle stimulating hormone in some experiments in cattle and.sheep, but other stud.es have failed.to find.an effect of peripheral injection of Kp on GH release. Recent stud.es ind.cate that Kp can stimulate GH release after intracerebroventricular injection in sheep at d.ses that d. not release GH after intravenous injection. These stud.es suggest that Kp may have a role in regulation of both reprod.ction and.metabolism in sheep. Since GH plays a role in luteal d.velopment, it is tempting to speculate that the ability of Kp to release GH and.LH is related.to normal control of reprod.ction.

关键词： Growth hormone Leptin Luteinizing Neuropeptid. Y POMC

Inhibition of Curcumin-Treated.Herpes Simplex Virus 1 and.2 in Vero Cells

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Ad.ances in Microbiology 2016年第4期6卷 276-287页

作者： daniel J. Flores Lee H. Lee Sand.a d. Ad.ms d.partment of Biology Montclair State University Montclair USA

The purpose of this stud. was to investigate the effect of curcumin-treated.Herpes simplex virus-1 (HSV-1) and.Herpes simplex virus-2 (HSV-2) virions in cultured.Vero cells. Previous stud.es have ind.cated.that curcumin, a polyphenol extracted.from the plant Curcuma longa, has d.monstrated.antiviral properties against a variety of viruses. After establishing the maximum non-cytotoxic concentrations of curcumin on Vero cells, HSV-1 and.HSV-2 virions were treated.with varying concentrations of curcumin. The effect on infectivity was d.termined.by antiviral assays, using WST-1, plaque assays, ad.orption and.penetration assays. Treating HSV-1 and.HSV-2 viruses with curcumin, at a concentration of 30 μM, red.ces the prod.ction of infectious HSV-1 and.HSV-2 virions in cultured.Vero cells by interfering with the ad.orption process. These results support the potential of curcumin to be used.as a therapeutic agent to red.ce the transmission of HSV-1 and.HSV-2.

关键词： HSV-1 HSV-2 Curcuma Longa Curcumin Vero Cells Ad.orption Antiviral