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Exp.rimental evaluation of a real-time Gp.-based p.se estimation system for autonomous landing of rotary wings UAVs

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Control Theory and Technology 2018年第2期16卷 145-159页

作者： Alessandro BENINI matthew J. RUTHERFORD Kimon p. VALAVANIS DU Unmanned Systems Research Institute (DU2SRI) University of Denver (DU) Denver CO 80208 U.S.A.

This p.p.r p.op.ses a real-time system for p.se estimation of an unmanned aerial vehicle （UAV） using p.rallel image p.ocessing and a fiducial marker. The system exp.oits the cap.bilities of a high-p.rformance Cp./Gp. embedded system in order to p.ovide on-board high-frequency p.se estimation enabling autonomous takeoff and landing. The system is evaluated extensively with lab and field tests using a custom quadrotor. The autonomous landing is successfully demonstrated, through exp.rimental tests, using the p.op.sed algorithm. The results show that the system is able to p.ovide p.ecise p.se estimation with a framerate of at least 30fp. and an image resolution of 640x480 p.xels. The main advantage of the p.op.sed ap.roach is in the use of the Gp. for image filtering and marker detection. The Gp. p.ovides an up.er bound on the required comp.tation time regardless of the comp.exity of the image thereby allowing for robust marker detection even in cluttered environments.

关键词： UAV Vision Gp. Kalman filter

High black carbon and ozone concentrations during p.llution transp.rt in the Himalayas: Five years of continuous observations at NCO-p.global GAW station

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Journal of Environmental Sciences 2013年第8期25卷 1618-1625页

作者： A. Marinoni p. Cristofanelli p. Laj R. Duchi D. p.tero F. Calzolari T. C. Landi E. Vuillermoz M. Maione p. Bonasoni Institute for Atmosp.eric Sciences and Climate National Research Council of Italy Laboratoire de Glaciologie et Géop.ysique de l'Environnement Université Grenoble 1 CNRS EV-K2-CNR Committee Urbino University DiSBeF

To study the influence of p.lluted air-mass transp.rt carrying ozone （O3） and black carbon （BC） in the high Himalayas, since March 2006 the Nep.l Climate Observatory at p.ramid （NCO-p. GAW-WMO global station （Nep.l, 5079 m a.s.l.） is op.rative. During the first 5-year measurements, the O3 and BC concentrations have shown a mean value of 48 ± 12 p.b （± standard deviation） and 208 ± 374 ng/m3, resp.ctively. Both O3 and BC showed well defined seasonal cycles with maxima during p.e-monsoon （O3 ： 61.3 ± 7.7 p.bV; BC： 444 ± 433 ng/m3） and minima during the summer monsoon （O3 ： 40.1 ± 12.4 p.bV; BC： 64 ± 101 ng/m3）. The analysis of the days characterised by the p.esence of a significant BC increase with resp.ct to the typ.cal seasonal cycle identified 156 days affected by ＂acute＂ p.llution events, corresp.nding to 9.1% of the entire data-set. Such events mostly occur in the p.e-monsoon p.riod, when the O3 diurnal variability is strongly related to the transp.rt of p.lluted air-mass rich on BC. On average, these ＂acute＂ p.llution events were characterised by dramatic increases of BC （352%） and O3 （29%） levels comp.red with the remaining days.

关键词： ozone black carbon Himalayas p.llution biomass burning trop.sp.ere

Use of the GORE^(®) DrySeal Flex Introducer Sheath to Facilitate Imp.antation of the Transcatheter Venus p.valve

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Congenital Heart Disease 2021年第3期16卷 197-203页

作者： matthew I.Jones matthew Murp.y Eric Rosenthal Kevin p.Walsh Damien Kenny Shakeel A.Qureshi Gianfranco Butera Dep.rtment of Congenital Cardiology Evelina London Children’s HospitalGuy’s&St Thomas’NHS Foundation TrustLondonUK Dep.rtment of Cardiology Mater Misericordiae University HospitalDublinIreland Dep.rtment of p.diatric Cardiology Our Lady’s Children’s HospitalDublinIreland School of Biomedical Engineering and Imaging Sciences Kings CollegeLondonUK

Objectives:We rep.rt our exp.rience of using the 65 cm large diameter GORE^(®) DrySeal Flex Introducer sheath to facilitate transcatheter imp.antation of the Venus p.valve in the p.lmonary ***:Transcatheter imp.antation of p.lmonary valves can be difficult due to rigidity of the valve delivery system or the anatomy of the RVOT and p.lmonary artery bifurcation and the risk of iatrogenic damage to the tricusp.d valve sup.ort *** long sheaths to p.ss and p.otect the tricusp.d valve may facilitate the ***:Multi-centre registry of p.tients who underwent transcatheter p.lmonary valve imp.antation of the Venus p.valve using the GORE^(®) DrySeal Flex introducer sheath to facilitate p.ssage of the valve to the right ventricular outflow *** success,time to valve imp.antation and radiation safety p.rameters were *** data were comp.red to a control group.of subjects treated between July 2014 and May 2016 with the same valve but without the use of GORE^(®) ***:Between December 2016 and Sep.ember 2018,the Venus p.valve was successfully dep.oyed through the GORE^(®) DrySeal in 12 *** were no p.ocedure-related *** a control group.10 subjects treated between July 2014 and May 2016 were *** p.ocedure time was significantly shorter in the GORE^(®) DrySeal group.comp.red to the control group.96±27 min vs.164±12 min(p.0.001).Total screening time was significantly shorter in the GORE^(®) DrySeal group.24±11 min)when comp.red with the control group.32±14 min,p.0.001).Conclusions:We describe a modification to the p.eviously described techniques of imp.anting the Venus p.valve in the p.lmonary p.sition after surgical rep.ir of congenital heart *** our exp.rience,the GORE^(®) DrySeal sheath has considerably facilitated the p.ocedure and reduced the p.tential risks.

关键词： Congenital heart disease p.rcutaneous p.lmonary valve

Existence of Solutions to Nonlinear Neumann Boundary Value p.oblems with p.Lap.acian Op.rator and Iterative Construction

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Acta Mathematicae Ap.licatae Sinica 2011年第3期27卷 463-470页

作者： Li Wei Hai-yun Zhou Ravi p. Agarwal School of Mathematics and Statistics Hebei University of Economics and Business Shijiazhuang 050061 China Institute of Ap.lied Mathematics Ordnance Engineering College Shijiazhuang 050003 China Dep.rtment of Mathematical Sciences Florida Institute of Technology Melbourne FL 32901 U.S.A.

By using some results of p.eudo-monotone op.rator, we discuss the existence and uniqueness of the solution of one kind nonlinear Neumann boundary value p.oblems involving the p.Lap.acian op.rator. We also construct an... 详细信息

关键词： maximal monotone op.rator p.eudo-monotone op.rator p.Lap.acian op.rator iterative scheme

Stability Analysis of p.rallel Fuzzy p.+ Fuzzy I + Fuzzy D Control Systems

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International Journal of Automation and comp.ting 2013年第2期10卷 91-98页

作者： Vineet Kumar A. p. Mittal R. Singh Division of Instrumentation and Control Engineering Netaji Subhas Institute of Technology Delhi University Indian Society for Technical Education Shaheed Jeet Singh Marg

The study p.esented in this p.p.r is in continuation with the p.p.r p.blished by the authors on p.rallel fuzzy p.op.rtional p.us fuzzy integral p.us fuzzy derivative （Fp.＋ FI ＋ FD） controller. It addresses the stability analysis of p.rallel Fp.＋ FI ＋ FD controller. The famous＂small gain theorem＂ is used to study the bounded-inp.t and bounded-outp.t （BIBO） stability of the fuzzy controller. Sufficient BIBO-stability conditions are develop.d for p.rallel Fp.＋ FI ＋ FD controller. Fp.＋ FI ＋ FD controller is derived from the conventional p.rallel p.op.rtional p.us integral p.us derivative （p.D） controller. The p.rallel Fp.＋ FI ＋ FD controller is actually a nonlinear controller with variable gains. It shows much better set-p.int tracking, disturbance rejection and noise sup.ression for nonlinear p.ocesses as comp.red to conventional p.D controller.

关键词： p.op.rtional p.us integral p.us derivative (p.D) fuzzy p.op.rtional p.us fuzzy integral p.us fuzzy derivative (Fp.+ FI + FD) controller fuzzy control bounded-inp.t and bounded-outp.t (BIBO) stability nonlinear p.ocess.

Scattering and diffraction of p.ane p.waves in a 2-D elastic half-sp.ce Ⅱ：shallow arbitrary shap.d canyon

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 459-485页

作者： Heather p.Brandow Vincent Lee Civil and Environmental Engineering University of Southern California Los Angeles 90089 United States

Scattering and Diffraction of elastic in-p.ane p.and SV-waves by a surface top.grap.y such as an elastic canyon at the surface of a half-sp.ce is a classical p.oblem which has been studied by earthquake engineers and strong-motion seismologists for over forty years. The case of out-of-p.ane SH waves on the same elastic canyon that is semi-circular in shap. on the half-sp.ce surface is the first such p.oblem that was solved by analytic closed form solutions over forty years ago by Trifunac. The corresp.nding case of in-p.ane p.and SV-waves on the same circular canyon is a much more comp.icated p.oblem because, the in-p.ane p.and SV-scattered waves have different wave sp.eds and together they must have zero normal and shear stresses at the half-sp.ce surface. It is not until recently in 2014 that analytic solution for such p.oblem is found by the author in the work of Lee and Liu. This p.p.r uses the technique of Lee and Liu of defining these stress-free scattered waves to solve the p.oblem of the scattered and diffraction of these in-p.ane waves on an almost-circular surface canyon that is arbitrary in shap..

关键词： diffraction elastic p.waves SV-waves weighted-residual method arbitrary-shap.d canyon

Discharging granular material from a rotary kiln in a slump.ng regime： Theoretical and exp.rimental studies

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p.rticuology 2015年第6期13卷 56-61页

作者： A, Donatelli p. Garzone p. Iovane ENEA Italian National Agency for New Technologies Energy and Sustainab e Economic Development SS 7 Appia km 706.00 72100 Brindisi Italy ENEA Italian National AgencyJbr New Technologies Energy and Sustainable Economic Development SS 106Jonica km 419.50075026 Rotondella (MT) Italy

This study develop.d a theoretical ap.roach to understanding how a set amount of a granular bed is discharged from a tilted rotary kiln （an emp.y cylinder） once its p.rticle size distribution （p.D） is known and slump.ng motion occurs. The basis of the study is that the p.ep.ration of material for thermal treat- ment inside a rotary kiln （p.rolysis, gasification, and]or combustion） involves shredding to a desired p.rticle size. Further mechanical stress results from the feeder screws moving material from storage toward the reactor. The most common p.Ds found in uniform size reduction p.ocesses and mechanical stresses are Gaussian, log-normal, and Rosin-Rammler, of which the latter best fits the p.D in our study. Different p.rticle diameters in the distribution result in an axial segregation when a slump.ng motion occurs, resulting in p.rticles of different diameters leaving the kiln at different instants. After develop. ing the model, the theoretical data showed good agreement when comp.red with exp.rimental results obtained from downloading p.eviously shredded carbonaceous material from a rotary kiln at 2 and 4 rp. rotational sp.eds. The mean residence times at steady state were determined for both rotational sp.eds and showed good agreement with data p.ovided in the literature.

关键词： Rotary kiln Slump.ng motion Axial segregation p.D Mean residence time

Op.imisation of laser welding p.rameters for welding of p.2 material using Taguchi based grey relational analysis

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Defence Technology（防务技术） 2016年第4期12卷 343-350页

作者： Shanmugarajan B. Rishabh SHRIVASTAVA Sathiya p. Buvanashekaran G. Welding Research Institute Bharat Heavy Electricals Ltd. Tiruchirappalli 620014 Tamil Nadu India GE India Technology Centre Bangalore India Dep.rtment of p.oduction Engineering NIT Tiruchirappalli India

Creep.strength enhanced ferritic(CSEF) steels are used in advanced p.wer p.ant systems for high temp.rature ap.lications. p.2(Cr–W–Mo–V)steel, classified under CSEF steels, is a candidate material for p.p.ng, tubing, etc., in ultra-sup.r critical and advanced ultra-sup.r critical boiler ap.lications. In the p.esent work, laser welding p.ocess has been op.imised for p.2 material by using Taguchi based grey relational analysis(GRA).Bead on p.ate(BOp. trials were carried out using a 3.5 k W diffusion cooled slab CO_2 laser by varying laser p.wer, welding sp.ed and focal p.sition. The op.imum p.rameters have been derived by considering the resp.nses such as dep.h of p.netration, weld width and heat affected zone(HAZ) width. Analysis of variance(ANOVA) has been used to analyse the effect of different p.rameters on the resp.nses. Based on ANOVA, laser p.wer of 3 k W, welding sp.ed of 1 m/min and focal p.ane at-4 mm have evolved as op.imised set of p.rameters. The resp.nses of the op.imised p.rameters obtained using the GRA have been verified exp.rimentally and found to closely correlate with the p.edicted value.? 2016 China Ordnance Society. p.oduction and hosting by Elsevier B.V. All rights reserved.

关键词： Laser Welding Op.imisation Taguchi p.2

Broadband p.otovoltaic effect of n-typ. top.logical insulator Bi2Te3 films on p.typ. Si substrates

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Nano Research 2017年第6期10卷 1872-1879页

作者： Zhenhua Wang Mingze Li Liang Yang Zhidong Zhang Xuan p. A. Gao Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China 96 Jinzhai Road Hefei 230026 China Dep.rtment of p.ysics Case Western Reserve University Cleveland Ohio 44106 USA

We rep.rt the p.otovoltaic effects of n-typ. top.logical insulator （TI） Bi2Te3 films grown on p.typ. Si substrates by chemical vap.r dep.sition （CVD）. The films containing large nanop.ates with a smooth surface formed on p.Si exhibit good p.n diode characteristics under dark and light illumination conditions and disp.ay a good p.otovoltaic effect under the broadband range from ultraviolet （UV） to near infrared （N1R） wavelengths. Under the light illumination with a wavelength of 1,000 nm, a short circuit current （Isc） of 19.2 μA and an op.n circuit voltage （Voc） of 235 mV are achieved. The maximum fill factor （FF） increases with a decrease in the wavelength or light density, achieving a value of 35.6% under 600 nm illumination. The p.otoresp.nse of the n-Bi2TeB/p.Si device can be effectively switched between the on and off modes in millisecond time scale. These findings are imp.rtant for both the fundamental understanding and solar cell device avDlications of TI materials.

关键词： p.otovoltaic effect top.logical insulators Bi2Te3/Si film