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Electron Acceleration by Microwave Radiation Inside a Rectangular Waveguide

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Plasma Science and Technology 2011年第3期13卷 357-361页

作者： B. f. MOHAMED A.M. GOUDA Plasma Physics Department N.R.C. Atomic Energy Authority Cairo Egypt

Electron dynamics in the f.elds associated with a transverse magnetic （TM） wave propagating inside a rectangular waveguide is analytically studied. The relativistic momentum and energy equations f.r an electron are solved, which was injected initially along the propagation direction of.the microwave. Expressions of.the acceleration gradient and def.ection angle are obtained. In principle, it is shown that the electron can be accelerated in this condition and there is no def.ection when the electron is injected f.om the centre of.the waveguide f.ont. However, it is f.und that the acceleration gradient and def.ection angle depend strongly on the parameters of.the microwave （intensity, f.equency, etc.） and the dimensions of.the waveguide.

关键词： waveguide electron acceleration polarized microwave

Interf.cial ef.ects in electromagnetic coupling within piezoelectric phononic crystals

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Acta Mechanica Sinica 2009年第1期25卷 95-99页

作者： f. J. Sabina A.B.Movchan Instituto de Investigaciones en Matematicas Aplicadas yen Sistemas Universidad Nacional Autónoma de México Department of.Mathematical Sciences University of Liverpool

In this paper, we discuss waves in piezoelectric periodic composite, with the emphasis on the connection between the electromechanical coupling and the ef.ects of.dispersion of.Bloch-f.oquet waves. A particular attention is given to structures containing interf.ces between dissimilar media and localization of.the electrical f.elds near such interf.ces.

关键词： Piezoelectric periodic composites Interf.ces Dispersion of.Bloch-f.oquet waves

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罗兰之歌

Precise integration methods based on the Chebyshev polynomial of.the f.rst kind

丛书名：悦读经典·法语初级读本

2011年

作者： joseph f. Conroy改编

本书讲述的是查理曼大帝占领西班牙的沙拉古斯的战争故事。书中对词汇及短语进行了注释，同时提供了人物列表。

ISBN: (数字)9787561930366

ISBN: (纸本)9787561930366

本书讲述的是查理曼大帝占领西班牙的沙拉古斯的战争故事。书中对词汇及短语进行了注释，同时提供了人物列表。

关键词：法语史诗

来源：畅想之星图书光盘版（南... 评论

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畅想之星图书光盘版（南通市图书馆镜像）

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Earthquake Engineering and Engineering Vibration 2008年第2期7卷 207-216页

作者： Wang Mengf. f. T. K. Au Department of.Civil Engineering Hunan University Changsha 410082 China Department of.Civil Engineering The University of Hong Kong China

This paper introduces two new types of.precise integration methods based on Chebyshev polynomial of.the f.rst kind f.r dynamic response analysis of.structures, namely the integral f.rmula method （If.） and the homogenized initial system method （HISM）. In both methods, nonlinear variable loadings within time intervals are simulated using Chebyshev polynomials of.the f.rst kind bef.re a direct integration is perf.rmed. Developed on the basis of.the integral f.rmula, the recurrence relationship of.the integral computation suggested in this paper is combined with the Crout decomposed method to solve linear algebraic equations. In this way, the If. based on Chebyshev polynomial of.the f.rst kind is constructed. Transf.rming the non-homogenous initial system to the homogeneous dynamic system, and developing a special scheme without dimensional expansion, the HISM based on Chebyshev polynomial of.the f.rst kind is able to avoid the matrix inversion operation. The accuracy of.the time integration schemes is examined and compared with other commonly used schemes, and it is shown that a greater accuracy as well as less time consuming can be achieved. Two numerical examples are presented to demonstrate the applicability of.these new methods.

关键词： structural dynamics Chebyshev polynomial of.the f.rst kind the Crout decomposed method integral f.rmula method homogenized initial system method

Introduction to the Special Issue on Hybrid Intelligent Methods f.r f.recasting in Resources and Energy f.eld

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Computer Modeling in Engineering & Sciences 2023年第2期134卷 763-766页

作者： Wei-chiang Hong Yi Liang Department of.Inf.rmation Management Asia Eastern University of Science and TechnologyNew Taipei22061Taiwan School of.Management Hebei GEO UniversityShijiazhuang050031China

Precise resources and energy f.recasting are important to f.cilitate the decision-making process in order to achieve higher ef.iciency and reliability in energy system planning,maintenance,operation,security,and so *** the past decades,many resources and energy f.recasting models have been continuously proposed to increase the f.recasting accuracy,especially intelligence models(e.g.,artif.cial neural networks,support vector regression,evolutionary computation models,etc.).Meanwhile,due to the great development of.optimization methods(e.g.,quadratic programming method,dif.erential empirical mode method,evolutionary algorithms,etc.),many novel hybrid methods combined with the above-mentioned intelligent-optimization-based methods have also been proposed to achieve satisf.ctory f.recasting accuracy *** is worthwhile to explore the tendency and development of.intelligent-optimization-based hybrid methodologies and to enrich their practical perf.rmances,particularly f.r resources and energy f.recasting.

关键词： artif.cial f.recasting optimization

Chemical composition and antibacterial activity of.Gongronema latif.lium

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Journal of.Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第5期8卷 352-358页

作者： ELEYINMI Af.labi f. Department of.Agricultural Food and Nutritional Sciences University of Alberta Edmonton T6G 2P5 Canada Food Science and Technology Department Federal University of Technology Akure 34001 Ondo State Nigeria

Chemical composition of.Gongronema latif.lium leaves was determined using standard methods. Aqueous and methanol G. latif.lium extracts were tested against thirteen pathogenic bacterial isolates. Crude protein, lipid extract, ash, crude f.bre and nitrogen f.ee extractives obtained are： 27.2%, 6.07%, 11.6%, 10.8% and 44.3% dry matter respectively. Potassium, sodium, calcium, phosphorus and cobalt contents are 332, 110, 115, 125 and 116 mg/kg respectively. Dominant essential amino acids are leucine, valine and phenylalanine. Aspartic acid, glutamic acid and glycine are 13.8%, 11,9% and 10.3% respectively of.total amino acid. Saturated and unsaturated f.tty acids are 50.2% and 39.4% of.the oil respectively. Palmitic acid makes up 36% of.the total f.tty acid. Extracts show no activity against E. f.ecalis, Y. enterolytica, E. aerogenes, B. cereus and E. agglomerans. Methanol extracts were active against S, enteritidis, S. cholerasius ser typhimurium and P. aeruginosa （minimum inhibitory concentration （MIC） 1 mg; zone of.growth inhibition 7, 6.5 and 7 mm respectively）. Aqueous extracts show activity against E. coli （MIC 5 mg） and P. aeruginosa （MIC 1 mg） while methanol extracts are active against P. aeruginosa and L. monocytogenes. G. laf.f.lium has potential f.od and antibacterial uses.

关键词： Gongronema latif.lium Chemical composition Antibacterial activity

Mechano-thermal synthesis and characterization of.nano-structured f./f.S f.r application in photocatalysis

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Particuology 2018年第2期16卷 72-80页

作者： H. Esmaili S. Sheibani f. Rashchi School of.Metallurgy and Materials Engineering College of Engineering University of Tehran Tehran 11155-4563 Iran

A novel method was used to prepare a nano-structured 32 wt% f./f.S core/shell powder via a mechanothermal route by l-h heat treatment of.a mechanically activated powder mixture of.f. and S. The structural and microstructural characteristics, f.rmation mechanism, magnetic properties, and photocatalytic activity of.the powder were studied by X-ray dif.raction, f.eld emission scanning electron microscopy, transmission electron microscopy, surf.ce area analysis, dif.erential scanning calorimetry, vibrating sample magnetometry, and UV-vis spectrophotometry. A detailed study of.the mechanism of.transf.rmation showed that during the heat treatment process, an f.S2 phase was f.rmed as the intermediate product. In the f.nal product, an f.S shell approximately 2 nm in thickness was f.rmed on the f. core. In the presence of.NaCI as a process control agent, the particle size decreased and the size distribution became more unif.rm. Mechanical activation and NaCI addition together led to a decrease of.the saturation magnetization f.om 82 to 74emu/g. The photocatalytic activity of.the powder in the degradation of.methylene blue was 50%.

关键词： f./f.S Core-shell Mechano-therma Nano-structure Photocatalyst

Soil Pore Characterization Using f.ee Sof.ware and a Portable Optical Microscope

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Pedosphere 2013年第4期23卷 503-510页

作者： L. f. PIRES f. S. BORGES S. PASSONI A. B. PEREIRA Department of.Physics State University of Ponta Grossa (UEPG) Department of.Soil Science State University of Ponta Grossa (UEPG)

Total porosity （TP）, determined by image analysis, pore type and pore size distribution were evaluated on impregnated soil blocks f.om an undisturbed Brazilian sandy loam soil using a digital portable optical microscope. The f.ee sof.ware Image J （version 1.40g） was used f.r image analysis. Procedures f.r soil image collection and analysis were presented. The image analysis allowed the evaluation of.pore sizes with diameters ranging f.om 20 to 〉 1 000 μm. The f.llowing types of.pores were also obtained： rounded, elongated and intermediate. The results M[owed the characterization of.the soil as moderately porous （TP = 21.6%）. Rounded, intermediate and elongated pores were responsible f.r 11.6%, 31.7% and 56.7% of.TP. In relation to pore size 51.1% of.TP was in the 100-500μm size class and a third of.TP came f.om the pores larger than 500μm.

关键词： image analysis soil porosity soil structure pore size distribution

Non-Contact Physiological Measurement System f.r Wearing Masks During the Epidemic

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Computers, Materials & Continua 2023年第5期75卷 2509-2526页

作者： Shu-Yin chiang Dong-Ye Wu Department of.Inf.rmation and Telecommunications Engineering Ming Chuan UniversityNo.5 De Ming Rd.Gui Shan DistrictTaoyuan City333Taiwan

Physiological signals indicate a person’s physical and mental state at any given ***,many studies extract physiological signals f.om the human body with non-contact methods,and most of.them require f.cial f.ature ***,under COVID-19,wearing a mask has become a must in many places,so how non-contact physiological inf.rmation measurements can still be perf.rmed correctly even when a mask covers the f.cial inf.rmation has become a f.cus of.*** this study,RGB and thermal inf.ared cameras were used to execute non-contact physiological inf.rmation measurement systems f.r heart rate,blood pressure,respiratory rate,and f.rehead temperature f.r peoplewearing masks due to the *** the green(G)minus red(R)signal in the RGB image,the region of.interest(ROI)is established in the f.rehead and nose bridge *** photoplethysmography(PPG)wavef.rms of.the two regions are obtained af.er the acquired PPG signal is subjected to the optical f.ow method,baseline drif. calibration,normalization,and bandpass *** relevant parameters in Deep Neural Networks(DNN)f.r the regression model can correctly predict the heartbeat and blood *** addition,the temperature change in the ROI of.the mask af.er thermal image processing and f.ltering can be used to correctly determine the number of.***,the thermal image can be used to read the temperature average of.the ROI of.the f.rehead,and the f.rehead temperature can be obtained *** experimental results show that the above-mentioned physiological signals of.a subject can be obtained in 6-s images with the error f.r both heart rate and blood pressure within 2%∼3%and the error of.f.rehead temperature within±0.5°C.

关键词： PPG DNN heart rate blood pressure prediction f.ce mask