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Mathematical model derivation of an unmanned circulation control aerial vehicle UC^2AV

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Control Theory and Technology 2020年第1期18卷 1-18页

作者： Mohammed AGHA Konstantinos KANISTRAS Matthew j.RUTHERFORD Kimon P.VALAVANIS University of Denver DenverCO80210U.S.A. University of Alabama Huntsville HuntsvilleAL35899U.S.A.

This paper presents a system identification method to derive accurate mathematical models for an unmanned circulation control aerial vehicle(UC2AV)that account for the effects of circulation control(CC)on the vehicle *** X-plane flight simulator and the CIFER system identification software are utilized to first derive simulation models to verify and validate the proposed system identification *** is followed by flight tests to derive mathematical models and stability derivatives for the aircraft with CC-on and *** tests indicate a nose down pitching moment effect induced by CC,which in turn alter the UAV trim values and *** of the two sets of mathematical models reveal that CC changes the longitudinal trim values and improves the lateral maneuverability of the *** experiments indicate an acceptable match between the derived models and UAV dynamics by calculating root mean square(RMS)error values and by quantifying the model predictive ability through calculating the Theil inequality coefficient(TIC).

关键词： Mathematical modeling control system UAV circulation control

Cavitation resistance of peduncle,petiole and stem is correlated with bordered pit dimensions in Magnolia grandiflora

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Plant Diversity 2021年第4期43卷 324-330页

作者： Feng-Ping Zhang jiao-Lin Zhang Timothy j.Brodribb Hong Hu CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303YunnanChina College of Traditional Chinese Medicine Yunnan Key Laboratory of Dai and Yi MedicinesYunnan University of Chinese MedicineKunming650500YunnanChina Key Laboratory of Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesYunnan Key Laboratory for Wild Plant ResourcesKunming 650201YunnanChina School of Natural Sciences University of TasmaniaPrivate Bag 55HobartTasmania 7001Australia

Variation in resistance of xylem to embolism among flowers,leaves,and stems strongly influences the survival and reproduction of ***,little is known about the vulnerability to xylem embolism under drought stress and their relationships to the anatomical traits of pits among reproductive and vegetative *** this study,we investigated the variation in xylem vulnerability to embolism in peduncles,petioles,and stems in a woody plant,Magnolia *** analyzed the relationships between water potentials that induced 50%embolism(P50)in peduncles,petioles,and stems and the conduit pit traits hypothesized to influence cavitation *** found that peduncles were more vulnerable to cavitation than petioles and stems,supporting the hypothesis of hydraulic vulnerability segmentation that leaves and stems are prioritized over flowers during drought ***,P50 was significantly correlated with variation in the dimensions of inter-vessel pit apertures among peduncles,petioles and *** findings highlight that measuring xylem vulnerability to embolism in reproductive organs is essential for understanding the effect of drought on plant reproductive success and mortality under drought stress.

关键词： Drought Flower Pit traits Xylem embolism Magnolia

iGluR expression in the hippocampal formation, entorhinal cortex, and superior temporal gyrus in Alzheimer’s disease

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Neural Regeneration Research 2022年第10期17卷 2197-2199页

作者： jason HY Yeung Henry j Waldvogel Richard LM Faull Andrea Kwakowsky Centre for Brain Research Department of Anatomy and Medical ImagingFaculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand

Alzheimer’s disease(AD)constitutes the largest proportion of dementia worldwide,with a significant associated medical *** major pathological hallmarks of AD include the gradual accumulation and deposition of amyloid-beta(Aβ)plaques and hyperphosphorylated tau protein(Revett et al.,2013).Whilst investigations centered around the tau and Aβhypothesis have been the main focus for the previous decades,the lack of therapeutic solutions has pushed for research into other potential therapeutic targets.

关键词： Alzheimer Aβ tau

Drawing-The Fusion of Inner and Outer

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Drawing-The Fusion of Inner and Outer

作者： CRISTIANO ASHLEY j 中国美术学院

学位级别：硕士

米哈里·契克森米哈的心流体验和弗雷德里克·弗兰克的冥想式的"看/画"将绘画过程描述为一种创造性的行为。在这个过程中,内在和外在的界限并不像日常正常的意识清醒状态下那样静止和一成不变的。绘画在很大程度上依赖于我们的主观感知... 详细信息

米哈里·契克森米哈的心流体验和弗雷德里克·弗兰克的冥想式的"看/画"将绘画过程描述为一种创造性的行为。在这个过程中,内在和外在的界限并不像日常正常的意识清醒状态下那样静止和一成不变的。绘画在很大程度上依赖于我们的主观感知,一种即是内在的也是外在的观察方式。它也依赖于眼睛部运动与手部运动的关联,并且在每时每刻与整个身体保持联系。我们在素描本中能够注意到自己的思想和情绪。这些思想和情绪形成的自我描述以前未被质疑。而素描本是使得我们可以选择新的、更有意义的叙事,并使我们对视角选择的力量保持清醒的认识。对中国传统艺术和手卷形式的探索揭示了叙事的本质和时间的碎片化,促进了内在和外在观察的同步。正是对我们的身体、思想的认识,以及随后对我们内心叙事的挑战,才能使艺术家达到一种心流的状态,并在绘画过程中彰显绘画变化莫测的本质。

关键词：心流注意沉思感知讲故事素描本心理时间

An extraordinary-performance gradient nanostructured Hadfield manganese steel containing multi-phase nanocrystalline-amorphous core-shell surface layer by laser surface processing

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journal of Materials Science & Technology 2023年第3期134卷 209-222页

作者： Wanting Sun jiasi Luo Yim Ying Chan j.H.Luan Xu-Sheng Yang Research Institute for Advanced Manufacturing Department of Industrial and Systems EngineeringThe Hong Kong Polytechnic UniversityHung HomHong KongChina Hong Kong Branch of National Rail Transit Electrification and Automation Engineering Technology Research Center The Hong Kong Polytechnic UniversityHung HomHong KongChina Department of Materials Science and Engineering City University of Hong KongHong KongChina

Reducing grain size(*** the fraction of grain boundaries)could effectively strengthen nanograined metals but inevitably sacrifices the ductility and possibly causes a strengthening-softening transition below a critical grain *** this work,a facile laser surface remelting-based technique was employed and optimized to fabricate a∼600μm-thick heterogeneous gradient nanostructured layer on an austenitic Hadfield manganese steel,in which the average grain size is gradually decreased from∼200μm in the matrix to only∼8 nm in the nanocrystalline-amorphous core-shell topmost ***-scale microstructural characterizations dissected the gradient refinement processes along the gradient direction,*** from the dislocations activities and twinning in sub-region to three kinds of martensitic transformations,and finally a multi-phase nanocrystalline-amorphous core-shell structural *** tests(***,bulk-specimen tensile,and micro-pillar compression)were conducted along the gradient *** confirms a tensile strength of∼1055 MPa and ductility of∼10.5%in the laser-processed ***,the core-shell structural surface maintains ultra-strong(tensile strength of∼1.6 GPa,micro-pillar compressive strength of∼4 GPa at a strain of∼8%,and nanoindentation hardness of∼7.7 GPa)to overcome the potential strengthening-softening *** significant strengthening effects are ascribed to the strength-ductility synergetic effects-induced extra work hardening ability in gradient nanostructure and the well-maintained dislocation activities inside extremely refined nanograins in the multi-phase nanocrystalline-amorphous core-shell structural surface,which are evidenced by atomic-scale observations and theoretical *** study provides a unique hetero-nanostructure through a facile laser-related technique for extraordinary mechanical performance.

关键词： Laser surface processing Hadfield manganese steel Gradient nanostructure Nanocrystalline-amorphous Martensitic transformation

Extra-pair paternity and antiparasitic defence

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Avian Research 2020年第4期11卷 391-397页

作者： Anders Pape Møller jørgen Skavdal Søraker juan joséSoler Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing 100875China Ecologie Systématique et Evolution UniversitéParis-SaclayCNRSAgroParisTech91405 OrsayFrance Centre for Biodiversity Dynamics Department of BiologyNorwegian University of Science and TechnologyHøgskoleringen 5No-7491TrondheimNorway Depto.Ecología Funcional y Evolutiva Estación Experimental de ZonasÁridasCtra.Sacramento S/NLa Cañada de San Urbano04120 AlmeríaSpain

Background:Extra-pair paternity(EPP)in birds provides benefits in terms of more offspring,and characteristics for maintenance of this behaviour have been the subject of *** are known to be transmitted during mating,especially when mating with multiple partners,and factors reducing this cost of multiple mating are ***,plumage brightness and colour intensity have been shown to be important traits to benefits from multiple mating as predicted by sexual *** aim of this study was to investigate the relationship between the rate of extra-pair paternity and the relative size of the uropygial gland at the interspecific level,as the uropygial gland is an exocrine gland hypothesized to produce antiparasitic substances and further identified to affect plumage *** of the expected benefits of large uropygial gland in scenarios of sexual selection,we predicted a positive correlation with ***:We collected information from the literature of uropygial gland size and frequency of extra-pair paternity of 60 avian species of different families and explored the predicted positive correlation between *** did so with means of comparative analyses that considered phylogenetic relationship as random factor and included body mass as *** used Markov chain Monte Carlo generalized linear mixed models that were weighted by number of nests used to estimate extra-pair ***:We detected a positive relationship between level of extra-pair paternity and uropygial gland size at an interspecific *** finding is consistent with the ***:We discuss the importance of this result in scenarios of sexual selection and argue that the detected relationship may have arisen by utilizing antiparasitic secretions through secondary sexual characters indicating parasite resistance.

关键词： Antiparasitic defence Costs of extra-pair paternity Microorganisms Uropygial gland Uropygial secretions

Robust design approach to the minimization of functional performance variations of products and systems

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Frontiers of Mechanical Engineering 2021年第2期16卷 379-392页

作者： j.ZHANG H.DU D.XUE P.GU Intelligent Manufacturing Key Laboratory of Ministry of Education Shantou UniversityShantou 515063 China Department of Mechanical and Manufacturing Engineering University of CalgaryCalgary T2N1N4Canada School of Mechanical Engineering Tianjin UniversityTianjin 300072China

Functional performance variations of products and systems are often used to measure the qualities of products and systems considering the changes in the design parameter values caused by uncertainties.A robust design approach has been developed in this research to minimize the functional performance variations considering the design parameter uncertainties by identifying the boundaries of the functional performance variations through *** this work,a mathematical model is developed to describe the relationships among functional performance,design configurations and parameters,and design parameter uncertainties.A multi-level optimization model is established to identify:(1)The optimal design configuration,(2)the optimal values of design parameters,and(3)the boundaries of functional performance *** analysis considering the impact of parameter uncertainties on functional performance variation boundaries has also been conducted.A case study on the design of a truss system has been *** study results show that the sensitivities of functional performance variation boundaries to the design parameter uncertainties can be reduced significantly using the new robust design approach.

关键词： product design robust design design optimization uncertainties

Interference from HONO in the measurement of ambient air NO2 via photolytic conversion and quantification of NO

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journal of Environmental Sciences 2021年第9期33卷 184-193页

作者： Nicholas j.Gingerysty Charles A.Odame-Ankrah Nick jordan Hans D.Osthoff Department of Chemistry University of CalgaryCalgary AB T2N 1N4Canada Global Analyzer Systems Ltd. Calgary AB T2E 7L6Canada

The reference method to quantify mixing ratios of the criteria air pollutant nitrogen dioxide(NO_(2)) is NO-O_(3) chemiluminescence(CL), in which mixing ratios of nitric oxide(NO) are measured by sampling ambient air directly, and mixing ratios of NO_(x)(= sum of NO and NO_(2))are measured by converting NO_(2) to NO using, for example, heated molybdenum catalyst or,more selectively, photolytic conversion(P-CL).In this work, the nitrous acid(HONO) interference in the measurement of NO_(2) by P-CL was *** with two photolytic NO2 converters are *** first used radiation centered at 395 nm, a wavelength region commonly utilized in *** second used light at 415 nm, where the overlap with the HONO absorption spectrum and hence its photolysis rate are *** ratios of NO_(2),NO_(x) and HONO entering and exiting the converters were quantified by Thermal Dissociation Cavity Ring-down Spectroscopy(TD-CRDS).Both converters exhibited high NO_(2) conversion efficiency(CF_(NO2);> 90%) and partial conversion of *** of CF against flow rate were consistent with photolysis frequencies of 4.2 s^(-1) and 2.9 s^(-1) for NO_(2) and 0.25 s^(-1) and 0.10 s^(-1) for HONO at 395 nm and 415 nm, *** larger than predicted from the overlap of the emission and HONO absorption *** results imply that measurements of NO2 by P-CL marginally but systematically overestimate true NO_(2) concentrations,and that this interference should be considered in environments with high HONO:NO_(2) ratios such as the marine boundary layer or in biomass burning plumes.

关键词： Photolytic conversion of NO_(2) HONO interference

Brain weight predicts yawn duration across domesticated dog breeds

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Current Zoology 2020年第4期66卷 401-405页

作者： Andrew C.Gallup Lea Moscatello jorg j.M.Massen Psychology Program Department of Social and Behavioral SciencesSUNY Polytechnic InstituteUticaNY13502USA Department of Psychology SUNY College at OneontaOneontaNY13820USA Animal Ecology Group Department of BiologyUtrecht UniversityPadualaan 8Utrecht CH3584The Netherlands

Previous research shows that yawning enhances intracranial circulation and regulates brain temperature. Consistent with these functional outcomes, yawn duration correlates positively with interspecies variation in brain weight across mammals, with robust relationships documented at both the taxonomic rank of class and the more restricted scale of family (e.g., Felidae). This study provides the first investigation into whether differences in brain weight within a single species, domesticated dogs Canis lupus familiaris, can predict intraspecific variation in yawn duration. Measures of yawn duration were obtained from public videos available online and then paired with previously published brain and body weight data of different dog breeds. The final sample consisted of 272 yawns from 198 dogs across 23 breeds. Consistent with recent studies, we find robust correlations between yawn duration and brain weight across breeds. Moreover, these correlations remain significant after controlling for differences in body weight across breeds. These findings replicate and extend upon past work in this area and provide further support that yawns evolved to serve an important and large-scale neurophysiologic function.

关键词： brain cooling brain size cortical arousal neuroanatomy