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A Novel Robust Attitude Control for Quadrotor Aircraft Subject to Actuator Faults and Wind Gusts

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IEEE/CAA Journal of Automatica Sinica 2018年第1期5卷 292-300页

作者： Yuying Guo Bin Jiang Youmin Zhang School of Information Engineering Southwest University of Science and Technology Mianyang 621010 China College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China department of Mechanical Industrial and Aerospace Engineering and the Concordia Institute of Aerospace Design and Innovation Faculty of Engineering and Computer Science Concordia University Montreal Quebec H3G 1M8 Canada IEEE

A novel robust fault tolerant controller is developed for the problem of attitude control of a quadrotor aircraft in the presence of actuator faults and wind gusts in this ***, a dynamical system of the quadrotor taking into account aerodynamical effects induced by lateral wind and actuator faults is considered using the Newton-Euler approach. Then,based on active disturbance rejection control(ADRC), the fault tolerant controller is proposed to recover faulty system and reject perturbations. The developed controller takes wind gusts,actuator faults and measurement noises as total perturbations which are estimated by improved extended state observer(ESO)and compensated by nonlinear feedback control law. So, the developed robust fault tolerant controller can successfully accomplish the tracking of the desired output values. Finally, some simulation studies are given to illustrate the effectiveness of fault recovery of the proposed scheme and also its ability to attenuate external disturbances that are introduced from environmental causes such as wind gusts and measurement noises.

关键词： Active disturbance rejection control(ADRC) attitude control actuator faults disturbances rejection quadrotor aircraft

A Proposed Method for Evaluating Management Feasibility When Determining Weed Control Priorities after Major Fires and Floods

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Research in Ecology 2023年第2期5卷 28-39页

作者： F.Dane Panetta School of Agriculture and Food Sustainability The University of QueenslandGattonQueensland4343Australia

Major fires and floods have enormous impacts on natural ecosystems and are predicted to increase in frequency with global *** managers need to make decisions on the prioritisation of weeds for control in post-disturbance landscapes,but little is available in the way of guidance to support timely decision ***-quantitative models(e.g.,scoring systems)have been employed routinely in weed risk assessment,which considers the potential impacts posed by weeds,as well as the likelihood of these impacts being *** progress has been made in the development of similar models addressing the topic of weed risk *** conditions prevailing after major disturbances,changes(both positive and negative)can be expected in the multiple factors that determine weed management feasibility,relative to pre-disturbance conditions.A semi-quantitative model is proposed that is based on the key factors that contribute to weed management feasibility in post-disturbance environments,along with annotated modules that could be used by land managers in both post-fire and post-flood *** fundamental challenge for weed management in these scenarios lies in the identification of differences between weeds and native species in relation to(1)patterns of seedling emergence;and(2)detectability relative to the growth *** two factors will determine the timing of control actions that are designed to address the trade-off between weed control and off-target damage during the period when both types of plants are recovering from a major disturbance *** model is intuitively sound,but field testing is required to determine both its practical value and any necessary improvement.

关键词： Maintenance control Natural ecosystems Semi-quantitative models Weed risk management

Biodiversity,current developments and potential biotechnological applications of phosphorus-solubilizing and-mobilizing microbes:A review

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Pedosphere 2021年第1期31卷 43-75页

作者： Divjot KOUR Kusam Lata RANA Tanvir KAUR Neelam YADAV Ajar Nath YADAV Manish KUMAR Vinod KUMAR Harcharan Singh DHALIWAL Anil Kumar SAXENA department of Biotechnology Dr.Khem Singh Gill Akal College of AgricultureEternal UniversityBaru SahibSirmour 173101(India Gopi Nath P.G.College Veer Bahadur Singh Purvanchal UniversityGhazipur 275201(India Amity Institute of Biotechnology Amity UniversityGwalior 474005(India Biochemistry Forage SectionCollege of AgricultureCCS Agricultural UniversityHaryana 125004India ICAR-National Bureau of Agriculturally Important Microorganisms Kusmaur 275103(India)

As one of the most important and essential macronutrients next to nitrogen,phosphorus(P)is important for plant development,but it is the least mobile nutrient element in plant and ***,P is mined from geological sediments and added to agricultural soils so as to meet the critical requirements of crop plants for agronomic *** exists in soil in both organic and inorganic *** various inorganic forms of the element in soil are salts with calcium,iron,and aluminum,whereas the organic forms come from decaying vegetation and microbial *** is a huge diversity of plant microbiomes(epiphytic,endophytic,and rhizospheric)and soil microbiomes that have the capability to solubilize the insoluble P and make it available to *** main mechanism for the solubilization of inorganic P is by the production of organic acids,which lowers soil pH,or by the production of acid and alkaline phosphatases,which causes the mineralization of organic *** P-solubilizing and-mobilizing microorganisms belong to all three domains,comprising archaea,bacteria,and *** strains belonging to the genera Arthrobacter,Bacillus,Burkholderia,Natrinema,Pseudomonas,Rhizobium,and Serratia have been reported as efficient and potential P *** use of P solubilizers,alone or in combination with other plant growth-promoting microbes as an eco-friendly microbial consortium,could increase the P uptake of crops,increasing their yields for agricultural and environmental sustainability.

关键词： crop improvement gene expression microbial diversity organic acid production P mineralization P solubilizer phosphatase production plant growth-promoting traits

Spatial Pattern of Rural Settlements in the Upper Reaches of the Minjiang River——a Case Study in Maoxian County, Sichuan

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Journal of Mountain Science 2007年第2期4卷 146-154页

作者： FENG Werdan LI Ainong ZHOU Wancun Chengdu Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu 610041SichuanChina Graduate School of Chinese Academy of Sciences Beijing 100039 China Chengdu Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu 610041Sichuan China

A quantitative analysis of the spatial pattern of rural settlements in the upper reaches of the Minjiang River was made with the major data sources being the relevant ETM image and the national geographical database of China （including contour line, fiver and road） at the scale of 1：250000, and using image interpretation and field investigation to obtain spatial information on rural settlements. The results of the spatial analysis technique of GIS and correlation analysis showed that most settlements （78.2 %） were located in the mountain area at 1500-2700 m altitude, and almost half in the arid valley area. More than 80.0 % of settlements had their slopes above 15°. Most settlements had good access to water resources, roads and communications, and tended to cluster close to the road network rather than the fiver. About half of the rural settlements in the study area were relatively concentrated, while the others were decentralized. Those with higher altitude usually had land with steep slope, inconvenient water and road accesses, and were located far apart from each other. In view of such a situation, further research should be done to make reasonable countermeasures on these settlements for better living conditions and ecosystem stability.

关键词： Rural settlement spatial pattern GIS Maoxian County China

Divergent male and female mate preferences do not explain incipient speciation between lizard lineages

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Current Zoology 2020年第5期66卷 485-492页

作者： Claire A.McLean Richard A.Bartle Caroline M.Dong Katrina J.Rankin Devi Stuart-Fox School of BioSciences The University of MelbourneParkville VIC 3010Australia Sciences department Museums VictoriaCarlton VIC 3053Australia

Diversification in sexual signals is often taken as evidenee for the importance of sexual selection in speciatio ***,in order for sexual selection to gen erate reproductive isolati on between populations,both signals and mate preferences must diverge ***,assortative mating may result from multiple behavioral mecha nisms,in eluding female mate pref ere nces,male mate preferences,and male-male competition;yet their relative contributions are rarely ***,we explored the role of mate pref ere nces and male competitive ability as pote ntial barriers to gene flow between 2 diverge nt lineages of the taw ny dragon lizard,Ctenophorus decresii,which differ in male throat *** found stronger behavioral barriers to pairings between southern lineage males and northern lineage females than between northern males and southern females,indicating incomplete and asymmetric behavioral isolating *** results were driven by both male and female mate preferences rather than lineage differences in male competitive *** trasexual selecti on is therefore un likely to drive the outcome of sec on dary contact in ***,despite its widely ack no wledged importa nee in *** results are consiste nt with the emergi ng view that although both male and female mate pref ere nces can diverge alongside sexual signals,speciation is rarely driven by divergent sexual selection alone.

关键词： Ctenophorus decresii hybridization male-male competition secondary contact sexual selection

Invasion genetics： Lessons from a ubiquitous bird, the house sparrow Passer domesticus

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Current Zoology 2015年第3期61卷 465-476页

作者： Andrea L. LIEBL Aaron W. SCHREY Samuel C. ANDREW Elizabeth L.SHELDON Simon C. GRIFFITH University of Exeter ComwaU Campus Penryn Cornwall TR10 9EZ UK department of Biology Armstrong State University Savannah GA31419 USA department of Biological Sciences Macquarie University Sydney NSW 2109 Australia

Following an introduction, non-native species are exposed to environments that differ from those found in their native range; further, as these non-native species expand beyond the site of introduction, they must constantly adapt to novel environ- ments. Although introduced species are present across most ecosystems, few species have successfully established themselves on a truly global scale. One such species, the house sparrow Passer domesticus, is now one of the world＇s most broadly distributed vertebrate species and has been introduced to a great part of its current range. To date, work on four continents suggests both ge- netic and phenotypic variation exists between native and introduced ranges. As such, house sparrows represent an excellent op- portunity to study adaptations to novel environments and how these adaptations are derived. The global distribution of this spe- cies and the multiple independent introductions to geographically isolated sites allow researchers to ask questions regarding ge- netic variation and adaptation on a global scale. Here, we summarize the molecular studies of invasive house sparrows from the earliest work using allozymes through more recent work on epigenetics; using these studies, we discuss patterns of dispersal of this species. We then discuss future directions in techniques （e.g. next generation sequencing） and how they will provide new in- sight into questions that are fundamental to invasion biology. Finally, we discuss how continued research on the house sparrow in light of these genetic changes and adaptations will elucidate answers of adaptation, invasion biology, range expansion, and resi- lience in vertebrate systems generally

关键词： House sparrow Invasive Passer domesticus

Denitrification in Chongming east tidal flat sediment, Yangtze estuary, China

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Science China Earth Sciences 2006年第10期49卷 1090-1097页

作者： WANG Dongqi1,2, CHEN Zhenlou1,3, XU Shiyuan1,2, HU Lingzhen1 & WANG Jun1,2 1. College of Resources & environment, East China Normal University, Shanghai 200062, China 2. State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics, East China Normal University, Shanghai 200062, China 3. Key Laboratory of Geographical Information Science of Ministry of Education,East China Normal University,Shanghai 200062, China 1. College of Resources & environment East China Normal University Shanghai 200062 China 2. State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics East China Normal University Shanghai 200062 China 3. Key Laboratory of Geographical Information Science of Ministry of Education East China Normal University Shanghai 200062 China

From July 2003 to July 2004, samples were collected on Chongming Island east tidal flat every two months. The research showed that the nitrous oxide (N2O) production rate was very low in the water, Chongming east tidal flat (CM) sediment was the N2O source of the water. Sediment N2O natural production rate was between -0.08 and 1.74 μmolN·m-2·h-1. N2O natural production rate was higher in the summer. The difference of the N2O natural production rate in the different tidal flats, the correlation between the N2O natural production rate and the denitrification rate, and those with the temperature and DO indicate that middle tidal flat sediment denitrification was the main process of the N2O production, while in the low tidal flat sediment, the production of the N2O came from several processes of the nitrogen cycling. Tidal flat sediment denitrification reaction was stronger in summer and winter but relatively lower in the late autumn and early spring. Seasonal change of the sediment denitrification rate was wide, from 1.12 to 33.34 μmolN·m-2·h-1. Temperature, DO and the coactions of them had the prominent effect on the tidal flat sediment denitrification.

关键词： Yangtze estuary, tidal flat sediment, denitrification, nitrous oxide, effect factor.

Probing atomic-scale symmetry breaking by rotationally invariant machine learning of multidimensional electron scattering

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npj Computational Materials 2021年第1期7卷 595-600页

作者： Mark P.Oxley Maxim Ziatdinov Ondrej Dyck Andrew R.Lupini Rama Vasudevan Sergei V.Kalinin Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTNUSA Computational Sciences and Engineering Division Oak Ridge National LaboratoryOak RidgeTNUSA

The 4D scanning transmission electron microscopy(STEM)method maps the structure and functionality of solids on the atomic scale,yielding information-rich data sets describing the interatomic electric and magnetic fields,structural and electronic order parameters,and other symmetry breaking distortions.A critical bottleneck is the dearth of analytical tools that can reduce complex 4D-STEM data to physically relevant *** propose an approach for the systematic exploration of 4D-STEM data using rotationally invariant variational autoencoders(rrVAE),which disentangle the general rotation of the object from other latent *** implementation of purely rotational rrVAE is discussed as are applications to simulated data for graphene and zincblende *** rrVAE analysis of experimental 4D-STEM data of defects in graphene is illustrated and compared to the classical center-of-mass *** approach is universal for probing symmetry-breaking phenomena in complex systems and can be implemented for a broad range of diffraction methods.

关键词： symmetry breaking rotational

Algae (Raphidocelis subcapitata) mitigate combined toxicity of microplastic and lead on Ceriodaphnia dubia

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Frontiers of environmental Science & Engineering 2020年第6期14卷 65-74页

作者： Xuesong Liu Jianmin Wang department o f Civil Architectural and Environmental EngineeringMissouri University of Science and TechnologyRollaMO 65409USA The Center for Research in Energy and environment(CREE) Missouri University of Science and TechnologyRollaMO 65409USA

Microplastics(MPs)have been recognized as a new class of emerging contaminants in recent *** not only directly impact aquatic organisms,but also indirectly impact these organisms by interacting with background toxins in the ***,under realistic environmental conditions,algae,a natural food for aquatic organisms,may alter the toxicity pattern related to *** this research,we first examined the toxicity of MPs alone,and their effect on the toxicity of lead(Pb)on Ceriodaphnia dubia(***),a model aquatic organism for toxicity ***,we investigated the effect of algae on the combined toxicity of MPs and *** observed that,MPs significantly increased Pb toxicity,which was related to the increase in soluble Pb concentration and the intake of Pb-loaded MPs,both of which increased the accumulation of Pb in *** presence of algae mitigated the combined toxicity of MPs and Pb,although algae alone increased Pb ***,the toxicity mitigation through algae uptake came from mechanisms other than Pb accumulation,which will need further investigation.

关键词： Microplastic Lead Toxicity Algae C.dubia