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Journal of Beijing Institute of Technology 2011年第3期20卷 339-344页

作者：李蒙刘莉 S.m.VERES School of Aerospace Engineering Beijing Institute of Technology School of Engineering Sciences University of Southampton

Aerodynamic parameter estimation provides an effective way for aerospace system modeling using measured data from flight tests, especially for the purpose of developing elaborate simulation environments and designing control systems of unmanned aerial vehicle （UAV） with short design cycles and reduced cost. However, parameter identification of airplane dynamics by nonlinear mod- els is complicated because of the noisy and biased sensor measurements. Using linear models for system identification is an alternative way if the fidelity can be guaranteed, as control design procedures are better established in linear systems. This paper considers the application and comparison of linear as well as nonlinear aerodynamic parameter estimation approaches of an UAV using unscented Kalman filter （UKF）. It also highlights the degree of deterioration of the linear model in the UKF identification process. The results show that both the linear and nonlinear methodologies can accurately estimate the control system design. Furthermore, considering loss of accuracy to be negligible, the linear model can be employed for control design of the UAV as presented here.

关键词： unmanned aerial vehicle aerodynamic parameter estimation unscented Kalman filter

Thermodynamical Bending of FGm Sandwich Plates Resting on Pasternak’s Elastic Foundations

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Advances in Applied mathematics and mechanics 2015年第1期7卷 116-134页

作者： mohammed Sobhy Ashraf m.Zenkour Department of mathematics Faculty of ScienceKing Faisal UniversityP.O.Box 400Hufof 31982Saudi Arabia Department of mathematics Faculty of ScienceKing Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia Department of mathematics Faculty of ScienceKafrelsheikh UniversityKafrelsheikh 33516Egypt

The analysis of thermoelastic deformations of a simply supported functionally graded material(FGm)sandwich plates subjected to a time harmonic sinusoidal temperature field on the top surface and varying through-the-thickness is illustrated in this *** FGm sandwich plates are assumed to be made of three layers and resting on Pasternak’s elastic *** volume fractions of the constituents of the upper and lower layers and,hence,the effective material properties of them are assumed to vary in the thickness direction only whereas the core layer is still *** in-plane sinusoidal variations of the displacements and the temperature that identically satisfy the boundary conditions at the edges,the governing equations of motion are solved analytically by using various shear deformation theories as well as the classical *** influences of the time parameter,power law index,temperature exponent,top-to-bottom surface temperature ratio,side-to-thickness ratio and the foundation parameters on the dynamic bending are investigated.

关键词： FGm sandwich plates dynamic bending elastic foundations thermal load

The Chromosomal Control of Leaf Characteristics of Early-Stage Plants in Wheat (Triticum aestivum L.)

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Agricultural Sciences in China 2011年第2期10卷 159-165页

作者： LI Cun-dong BAI Zhi-ying Ye G miyagi m Chapman S Reader S m LIU Chun-ji CSIRO Plant Industry Queensland Bioscience PrecinctSt LuciaQLD 4067Australia Faculty of Agriculture Hebei Agricultural UniversityBaoding 071000P.R.China College of Life Science Hebei Agricultural UniversityBaoding 071000P.R.China School of Land and Food Sciences University of QueenslandSt LuciaQLD 4072Australia John Innes Centre Norwich Research ParkColney NorwichNR4 7UHUK

Rapid expansion of leaves of early-stage plants in wheat produced by chromosomal control of characteristics related to rapid expansion of the first six leaves of wheat were investigated using a set of single chromosome substitution lines under two different temperature regimes（TRs）.Results from this study indicated that several chromosomes could be responsible for each of the four characteristics studied（including leaf width,leaf length,leaf elongation rate and leaf appearance index） and that different chromosomes may be responsible for the same characteristics at different *** a small number of substitutions that showed the most significant effects on leaf length were found among those that showed the most significant effects on leaf width,providing further evidence that these two characteristics are likely controlled by different sets of *** 4B,4D,and 5A are among those that were repeatedly detected to having significant effects on different leaf characteristics at the lower-TR and genes residing on these three chromosomes could be *** possibility and its implication are discussed.

关键词： wheat leaf characteristics chromosomal control

Comparison of Energy Harvesting Systems for Wireless Sensor Networks

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International Journal of Automation and computing 2008年第4期5卷 334-347页

作者： James m.Gilbert Farooq Balouchi Department of Engineering University of Hull

Wireless sensor networks (WSNs) offer an attractive solution to many environmental,security,and process monitoring ***,one barrier to their fuller adoption is the need to supply electrical power over extended periods of time without the need for dedicated *** harvesting provides a potential solution to this problem in many *** paper reviews the characteristics and energy requirements of typical sensor network nodes,assesses a range of potential ambient energy sources,and outlines the characteristics of a wide range of energy conversion *** then proposes a method to compare these diverse sources and conversion mechanisms in terms of their normalised power density.

关键词： Energy harvesting energy scavenging wireless sensor networks (WSNs) energy management

Bimodal imaging of proliferative diabetic retinopathy vascular features using swept source optical coherence tomography angiography

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International Journal of Ophthalmology(English edition) 2018年第9期11卷 1528-1533页

作者： Amal m Elbendary Hossam Youssef Abouelkheir mansoura Ophthalmic Center Mansoura University

AIm： To categorize neovessels morphology and to detect response to anti-angiogenic therapy by using structural and angiographic modes of swept source optical coherence tomography（SS-OCT）.mETHODS： Thirty-two eyes with neovessels at disc（NVD） and neovessels elsewhere（NVE）-as diagnosed by fluorescein angiography-were included. Cross sectional OCT images of disc and macular regions were registered to enface OCT angiography（OCTA）, B-scan blood flow over lay and density maps. Three eyes received antiangiogenic ***： Pin point registration of cross-sectional OCT and OCTA images differentiated active NVD with vascular elements from fibrous or equivalent fibrovascular elements. En face images delineated NVE as vascular tufts or area of filling while cross-sectional images differentiated NVE from microvascular intraretinal abnormality（IRmA）. All cases were associated with enlargement of foveal avascular zone and or areas of capillary non perfusion. Regressed NVD appeared as ghost vessel or pruned vascular loops after ***： Structural and angiographic modes of SS-OCT can detect, characterize and categorize the pattern of wide spectrum of neovessels based on blood flow data and density maps. It is potentially useful to detect ischemic changes in the vascular bed and regression of NVD after therapeutic regimens providing substitute for invasive techniques.

关键词： optical coherence tomography angiography swept proliferative diabetic retinopathy

Design of Six Element mImO Antenna with Enhanced Gain for 28/38 GHz mm-Wave 5G Wireless Application

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Computer Systems Science & Engineering 2023年第8期46卷 1689-1705页

作者： K.Jayanthi A.m.Kalpana Department of Electronics and Communication Engineering Government College of EngineeringSalemIndia Department of Computer Science and Engineering Government College of EngineeringSalemIndia

The fifth-generation(5G)wireless technology is the most recent standardization in communication services of interest across the *** concept of multiple-Input-multiple-Output antenna(mImO)systems has recently been incorporated to operate at higher frequencies without *** paper addresses,design of a high-gain mImO antenna that offers a bandwidth of 400 mHz and 2.58 GHz by resonating at 28 and 38 GHz,respectively for 5G millimeter(mm)-wave *** proposed design is developed on a RT Duroid 5880 substrate with a single elemental dimension of 9.53×7.85×0.8 mm^(3).The patch antenna is fully grounded and is fed with a 50-ohm stepped impedance microstrip *** also has an I-shaped slot and two electromagnetically coupled parasitic slotted *** design is initially constructed as a single-element structure and proceeded to a six-element mImO antenna configuration with overall dimensions of 50×35×0.8 mm^(3).The simulated prototype is fabricated and measured for analyzing its performance characteristics,along with mImO antenna diversity performance factors making the proposed antenna suitable for 5G mm-wave and 5G-operated handheld devices.

关键词： mImO antenna parasitic elements 5G mm-wave dual band frequency diversity factors

multi-label Emotion Classification of COVID–19 Tweets with Deep Learning and Topic modelling

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Computer Systems Science & Engineering 2023年第6期45卷 3005-3021页

作者： K.Anuratha m.Parvathy Department of Information Technology Sri Sai Ram Institute of TechnologyChennaiTamilnaduIndia Department of Computer Science and Engineering Sethu Institute of TechnologyMaduraiTamilnaduIndia

The COVID-19 pandemic has become one of the severe diseases in recent *** it majorly affects the common livelihood of people across the universe,it is essential for administrators and healthcare professionals to be aware of the views of the community so as to monitor the severity of the spread of the *** public opinions are been shared enormously in microblogging med-ia like twitter and is considered as one of the popular sources to collect public opinions in any topic like politics,sports,entertainment etc.,This work presents a combination of Intensity Based Emotion Classification Convolution Neural Net-work(IBEC-CNN)model and Non-negative matrix Factorization(NmF)for detecting and analyzing the different topics discussed in the COVID-19 tweets as well the intensity of the emotional content of those *** topics were identified using NmF and the emotions are classified using pretrained IBEC-CNN,based on predefined intensity *** research aimed at identifying the emotions in the Indian tweets related to COVID-19 and producing a list of topics discussed by the users during the COVID-19 *** the Twitter Application Programming Interface(Twitter API),huge numbers of COVID-19 tweets are retrieved during January and July *** extracted tweets are ana-lyzed for emotions fear,joy,sadness and trust with proposed Intensity Based Emotion Classification Convolution Neural Network(IBEC-CNN)model which is *** classified tweets are given an intensity score varies from 1 to 3,with 1 being low intensity for the emotion,2 being the moderate and 3 being the high *** identify the topics in the tweets and the themes of those topics,Non-negative matrix Factorization(NmF)has been *** of emotions of COVID-19 tweets has identified,that the count of positive tweets is more than that of count of negative tweets during the period considered and the negative tweets related to COVID-19 is less than 5%.Also,more than 75%neg

关键词： Twitter topic detection emotion classification COVID-19 corona virus non-negative matrix factorization(NmF) convolutional neural network(CNN) sentiment classification healthcare

The influence of fire frequency on the abundance of maerua subcordata in the Serengeti National Park, Tanzania

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Journal of Plant Ecology 2012年第4期5卷 400-406页

作者： Ayron m.Strauch Stephanie Eby Department of Biology Tufts University163 Packard AvenueMedfordMA 02155USA Department of Ecology and Evolutionary Biology 106A Guyot HallPrinceton UniversityPrincetonNJ 08544USA Present address:Department of Ecology and Evolutionary Biology Yale UniversityPO Box 208106165 Prospect StreetNew HavenCT 06520-8106USA

Aims Invasive species alter the composition and function of communities,threatening the conservation of important ecosystems *** savanna ecosystems,fire plays a key role by modifying biogeochemical cycles and shaping the composition and structure of vegetation *** many studies have examined the long-term effects of fire frequency on grassland communities,few studies have examined the relationship between fire regime and woody species *** The Serengeti ecosystem is an ecologically and economically valuable natural resource in East Africa whose conservation is currently threatened by a variety of factors,including invasive *** determined the abundance of maerua subcordata,a noxious woody shrub,in three different regions of the Serengeti National Park,*** then examined the influence of fire frequency,developed through the use of 7 years of moderate Resolution Imaging Spectroradiometer(mODIS)imagery,on *** *** Findings In all regions,burned transects had significantly greater abundances of *** compared to unburned ***,the number of times each transect burned from 2000 to 2006 had a significant positive effect on the abundance of *** and the number of years since a transect last burned had a significant negative relationship with *** results are particularly important as this species provides little forage value and is potentially toxic to wildlife and *** studies are needed to determine the ecological consequences of increasing *** abundance,as the potential expansion of noxious shrubs into protected areas of important conservation status is of serious concern.

关键词： Serengeti fire savanna maerua subcordata mODIS

Predictive-Analysis-based machine Learning model for Fraud Detection with Boosting Classifiers

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Computer Systems Science & Engineering 2023年第4期45卷 231-245页

作者： m.Valavan S.Rita Department of Statistics Periyar UniversitySalemTamilnaduIndia

Fraud detection for credit/debit card,loan defaulters and similar types is achievable with the assistance of machine Learning(mL)algorithms as they are well capable of learning from previous fraud trends or historical data and spot them in current or future *** cases are scant in the comparison of non-fraudulent observations,almost in all the *** such cases detecting fraudulent transaction are quite *** most effective way to prevent loan default is to identify non-performing loans as soon as *** learning algorithms are coming into sight as adept at handling such data with enough computing *** this paper,the rendering of different machine learning algorithms such as Decision Tree,Random Forest,linear regression,and Gradient Boosting method are compared for detection and prediction of fraud cases using loan fraudulent *** model accuracy metric have been performed with confusion matrix and calculation of accuracy,precision,recall and F-1 score along with Receiver Operating Characteristic(ROC)curves.

关键词： Random forest decision tree logistic regression machine Learning gradient boosting method confusion matrix

Effect of substituents in hydroxyl radical-mediated degradation of azo pyridone dyes: Theoretical approaches on the reaction mechanism

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Journal of Environmental Sciences 2020年第12期32卷 14-21页

作者： J.Dostanic m.Hus D.Loncarevic Institute of Chemistry Technology and MetallurgyUniversity of Belgrade(National Institute)Department of Catalysis and Chemical EngineeringNjegoševa 12BelgradeRepublic of Serbia Department of Catalysis and Chemical Reaction Engineering National Institute of ChemistryHajdrihova 19LjubljanaSlovenia

Understanding the degradation behavior of azo dyes in photocatalytic wastewater treatment is of fundamental and practical importance for their application in textile-processing and other coloration industries. In this study, quantum chemistry, as density functional theory, was used to elucidate different degradation pathways of azo pyridone dyes in a hydroxyl radical(HO ·)-initiated photocatalytic system. A series of substituted azo pyridone dyes were synthesized by changing the substituent group in the para position of the benzene moiety, ranging from strong electron-donating to strong electron-withdrawing groups. The effect of dye molecular structure on the photocatalytic degradation reaction mechanism was analyzed and quantification of substituent effects on the thermodynamic and kinetics parameters was performed. Potential energy surface analysis revealed the most susceptible reaction site for the HO ·attack. The calculated reaction barriers are found to be strongly affected by the nature of substituent group with a good correlation using Hammett σp constants and experimentally determined reaction rates. The stability of pre-reaction complexes and transition state complexes were analyzed applying the distortion-interaction model. The increased stability of the transition state complexes with the distancing from the substituent group has been established.

关键词： Quantum chemical calculation Density functional theory Azo dye Reaction mechanism Photocatalytic degradation Hydroxyl radical Hammett equation Substituent effect