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Nucleon transition form factors at JLab:status and outlook

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Chinese Physics C 2009年第12期33卷 1216-1221页

作者： R. w. Gothe University of South Carolina Columbia SC 29208 USA

The measurements of exclusive single-meson and double-pion electro-production cross sections off the proton to study nucleon resonances w.ll be extended to higher momentum transfers w.th the CLAS12 detector and the energy upgraded CEBAF beam. Based on new.theoretical developments to extract and interpret the electromagnetic transition form factors and on the experience gained from the most recent results, the new.y formed collaboration of experimentalists and theorists shall enable us to provide unprecedented high- precision data, high-quality analyses, and state-of-the-art model and QCD based calculations in a Q2 domain up to 10 GeV2. For the first time nucleon resonance structures w.ll be studied at still unexplored distance scales, w.ere the dressed quark contributions are the dominating degrees of freedom and their strong interaction is responsible for the ground and excited nucleon state formation. These studies also open up a promising opportunity to understand the origin of more than 98% of the nucleon mass that is created by strong fields predominantly at these distance scales by dressing the current quarks.

关键词： baryon structure strong degrees of freedom

N4SID and MOESP Algorithms to Highlight the Ill-conditioning into Subspace Identification

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International Journal of Automation and computing 2014年第1期11卷 30-38页

作者： Slim Hachicha maher Kharrat Abdessattar Chaari Laboratory of Sciences and Techniques of Automatic Control and Computer Engineering (Lab-STA) National School of Engineering of SfaxUniversity of Sfax

In this paper,an analysis for ill conditioning problem in subspace identifcation method is *** subspace identifcation technique presents a satisfactory robustness in the parameter estimation of process model w.ich performs *** a frst step,the main geometric and mathematical tools used in subspace identifcation are briefly *** the second step,the problem of analyzing ill-conditioning matrices in the subspace identifcation method is *** illustrate this situation,a simulation study of an example is introduced to show.the ill-conditioning in subspace *** numerical subspace state space system identifcation(N4SID)and multivariable output error state space model identifcation(MOESP)are considered to study,the parameters estimation w.ile using the induction motor model,in simulation(Matlab environment).Finally,w. show.the inadequacy of the oblique projection and validate the efectiveness of the orthogonal projection approach w.ich is needed in ill-conditioning;a real application dealing w.th induction motor parameters estimation has been *** obtained results proved that the algorithm based on orthogonal projection MOESP,overcomes the situation of ill-conditioning in the Hankel s block,and thereby improving the estimation of parameters.

关键词： Subspace identification ill-conditioning oblique projection orthogonal projection algorithms numerical subspace state space system identification (N4SID) multivariable output error state space model identification (MOESP) induction motor

On the truth of nanoscale for nanobeams based on nonlocal elastic stress field theory:equilibrium,governing equation and static deflection

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Applied Mathematics and Mechanics(English Edition) 2010年第1期31卷 37-54页

作者： C. w. LIM Department of Building and Construction City University of Hong Kong

This paper has successfully addressed three critical but overlooked issues in nonlocal elastic stress field theory for nanobeams：（i） w.y does the presence of increasing nonlocal effects induce reduced nanostructural stiffness in many, but not consistently for all, cases of study, i.e., increasing static deflection, decreasing natural frequency and decreasing buckling load, although physical intuition according to the nonlocal elasticity field theory first established by Eringen tells otherw.se？（ii） the intriguing conclusion that nanoscale effects are missing in the solutions in many exemplary cases of study, e.g., bending deflection of a cantilever nanobeam w.th a point load at its tip; and （iii） the non-existence of additional higher-order boundary conditions for a higher-order governing differential equation. Applying the nonlocal elasticity field theory in nanomechanics and an exact variational principal approach, w. derive the new.equilibrium conditions, do- main governing differential equation and boundary conditions for bending of nanobeams. These equations and conditions involve essential higher-order differential terms w.ich are opposite in sign w.th respect to the previously studies in the statics and dynamics of nonlocal nano-structures. The difference in higher-order terms results in reverse trends of nanoscale effects w.th respect to the conclusion of this paper. Effectively, this paper reports new.equilibrium conditions, governing differential equation and boundary condi- tions and the true basic static responses for bending of nanobeams. It is also concluded that the w.dely accepted equilibrium conditions of nonlocal nanostructures are in fact not in equilibrium, but they can be made perfect should the nonlocal bending moment be replaced by an effective nonlocal bending moment. These conclusions are substantiated, in a general sense, by other approaches in nanostructural models such as strain gradient theory, modified couple stress models and experim

关键词： bending effective nonlocal bending moment nanobeam nanomechanics,nanoscale nonlocal elastic stress strain gradient

General Theoretical Model for Resonantly Enhanced Optical Modulators

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光学学报 2003年第S1期23卷 337-338页

作者： Yuvaraja S. Visagathilagar Arnan Mitchell michael w. Austin Australian Photonics CRC SECE RMIT University GPO Box 2476V MelbourneVictoria3001Australia.Australian Photonics CRC SECE RMIT University GPO Box 2476V MelbourneVictoria3001Australia.Australian Photonics CRC SECE RMIT University GPO Box 2476V MelbourneVictoria3001Australia.

1 IntroductionLiNbO3 optical modulators have become essential transmission devices for current and future w.deband fibre-optic communications for both military and telecommunications applications. For many telecommunications applications, only a narrow.bandw.dth is required and thus resonantly enhancedMach-Zehndermodulators(RE-MZMs)have been developed to improve modulation efficiency at the expense of bandw.dth.

关键词： for on et of in be General Theoretical Model for Resonantly Enhanced Optical Modulators MZM

Impact of Human Vulnerabilities on Cybersecurity

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Computer Systems Science & Engineering 2022年第3期40卷 1153-1166页

作者： maher Alsharif Shailendra Mishra Mohammed AlShehri Department of Information Technology College of Computer and Information SciencesMajmaah UniversityMajmaah11952Saudi Arabia Department of Computer Engineering College of Computer and Information SciencesMajmaah UniversityMajmaah11952Saudi Arabia

Today,security is a major challenge linked w.th computer netw.rk companies that cannot defend against *** vulnerable factors increase security risks and cyber-attacks,including viruses,the internet,communications,and *** of Things(IoT)devices are more effective,and the number of devices connected to the internet is constantly increasing,and governments and businesses are also using these technologies to perform business activities ***,the increasing uses of technologies also increase risks,such as passw.rd attacks,social engineering,and phishing *** play a major role in the field of *** is observed that more than 39%of security risks are related to the human factor,and 95%of successful cyber-attacks are caused by human error,w.th most of them being insider *** major human factor issue in cybersecurity is a lack of user aw.reness of cyber *** study focuses on the human factor by surveying the vulnerabilities and reducing the risk by focusing on human nature and reacting to different *** study highlighted that most of the participants are not experienced w.th cybersecurity threats and how.to protect their personal ***,the lack of aw.reness of the top three vulnerabilities related to the human factor in cybersecurity,such as phishing attacks,passw.rds,attacks,and social engineering,are major problems that need to be addressed and reduced through proper aw.reness and training.

关键词： Cybersecurity phishing attack passw.rd attack social engineering cybersecurity aw.reness security risk

ON GRAPH MEASURES IN BANACH SPACES AND DESCRIPTION OF ESSENTIAL SPECTRA OF MULTIDIMENSIONAL TRANSPORT EQUATION

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Acta Mathematica Scientia 2012年第5期32卷 2050-2064页

作者： Boulbeba Abdelmoumen Aref Jeribi maher Mnif Dpartement de Mathmatiques Universit de SfaxFacult des Sciences de SfaxRoute de SoukraKm 3.5B.P.11713000SfaxTunisie

In this paper,w. define new.measures called respectively graph measure of noncompactness and graph measure of w.ak ***,w. apply the obtained results to discuss the incidence of some perturbation results realized in [2] on the behavior of essential spectra of such closed densely defined linear operators on Banach *** results are exploited to investigate the essential spectra of a multidimensional neutron transport operator on L1 spaces.

关键词： measures of noncompactness and w.ak noncompactness in Banach spaces Fredholm operators essential spectra

NOTES ON “MULTICRITERIA FUZZY DECISION-MAKING METHOD BASED ON A NOVEL ACCURACY FUNCTION UNDER INTERVAL-VALUED INTUITIONISTIC FUZZY ENVIRONMENT”

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Journal of Systems Science and Systems Engineering 2010年第4期19卷 504-508页

作者： Kevin w. LI Zhoujing w.NG Odette School of Business University of Windsor Windsor Ontario N9B 3P4 Canada School of Computer Science and Engineering Beihang University Beijing 100083 China Department of Automation Xiamen University Xiamen Fujian 361005 China

This note points outs the inappropriateness of an accuracy function introduced by Ye [Ye, J. （2009）. Multicriteria fuzzy decision-making method based on a novel accuracy function under interval-valued intuitionistic fuzzy environment. Expert Systems w.th Applications, 36 （3）： 6899-6902] and its misleading use for comparing tw. interval-valued intuitionistic fuzzy numbers.

关键词： Interval-valued intuitionistic fuzzy set accuracy function score function multicriteria decision-making

Influence of concentration and sintering temperature on luminescence properties of Eu^(3+):SnO_2 nanocrystallites

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Journal of Rare Earths 2012年第7期30卷 627-631页

作者： P. Psuja w. Strek Institute of Low.Temperature and Structure Research of Polish Academy of Sciences

The nanopow.ers of SnO2 doped w.th different Eu^3＋ concentrations w.re synthesized using the modified Pechini method. The Eu^3＋ concentrations w.re high above solubility limit. The average size of crystallites w.s controlled by the sintering temperatures. The structure and the morphology of obtained pow.ers w.re examined using the XRD （X-ray diffraction） and TEM （transmission electron microscopy） analyses. The Eu2Sn2O7 phase separation w.s observed at relatively high concentration of Eu^3＋ ions. The ZnS：Ag micropow.ers w.re mixed w.th the Eu^3＋：SnO2 pow.ers and their normalized emission w.s used to measure a relative efficiency of Eu3＋：SnO〉 The photoluminescence spectra of mixed pow.ers w.re measured in function of Eu^3＋ concentration and average size of nanocrystallites. The reference peak method w.s used for comparison of intensities of the samples and selection of optimal one. The influence of the average grain size and Eu^3＋ concentration on the phosphor＇s efficiency w.s discussed. The presented results confirmed the rightness of synthesis of the Eu^3＋：SnO2 in form of nanocrystalites w.th relatively high Eu^3＋ concentration.

关键词： SnO2 nanocrystallites Eu^3+ luminescence phosphors rare earths

Supercritical fluids:Clean solvents for green chemistry

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Chinese Journal of Chemistry 1999年第3期17卷 212-222,201页

作者： POLIAKOFF Martyn GEORGE michael w. HOw.LE Steven M. BAGRATASHVILI Viktor N. 韩布兴闫海科 LaserChem Scientific Centre for Technological Lasers of the Russian Academy of Sciences Troitzk (Moscow Region) Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Department of Chemistry The University of Nottingham Nottingham NG7 2RD England

Supercritical fluids are becoming increasingly attractive as environmentally acceptable replacement for organic solvents in chemical reactions and material processing. This paper highlights some of the properties of supercritical fluids, especially supercritical CO2, w.ich offer particular advantages for the handling of polymers, metal complexes and the environmentally more friendly synthesis and manufacture of chemicals. The paper includes same of the researches in University of Nottingham and a number of recent review. w.ich together provide a comprehensive introduction.

关键词： Green chemistry supercritical fluids chemical reaction w.ter rapid expansion antisolvent