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Correction of failure in antenna array using matrix pencil technique

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Chinese Physics B 2017年第6期26卷 491-498页

作者： S u Khan M K A Rahim Advanced RF & Microwave Research Group Department of Communication Engineering Faculty of Electrical Engineering Universiti Teknologi Malaysia 81310 Skudai Johor Malaysia

In this paper a non-iterative technique is developed for the correction of faulty antenna array based on matrix pencil technique（mpT）. The failure of a sensor in antenna array can damage the radiation power pattern in terms of sidelobes level and nulls. In the developed technique, the radiation pattern of the array is sampled to form discrete power pattern information set. Then this information set can be arranged in the form of Hankel matrix（HM） and execute the singular value decomposition（SVD）. By removing nonprincipal values, we obtain an optimum lower rank estimation of HM. This lower rank matrix corresponds to the corrected pattern. Then the proposed technique is employed to recover the weight excitation and position allocations from the estimated matrix. Numerical simulations confirm the efficiency of the proposed technique, which is compared with the available techniques in terms of sidelobes level and nulls.

关键词： array correction low rank estimation matrix pencil technique singular value decomposition

Pulmonary Toxicity of a Formulated Preparation of Fenvalerate in Rats Subchronically Exposed by Nose Only Inhalation for 90 Days

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Biomedical and Environmental Sciences 2001年第4期14卷 333-340页

作者： u.MANI FAKRuLISLAM 等 InhalationToxicologyLaboratory IndustrialToxicologyResearchCentreM.G.MargP.Box.No.80M.G.MargLucknow－226001India DepartmentofMedicalElementolgoy＆Toxicology HamdardUniversityNewDelhi

Objective The pulmonary toxicity of a commercially available formulated preparation of Fenvalerate (Fen), a synthetic pyrethroid has been studied in rats following subchronic nose only inhalation exposure route. Method Adult male rats were exposed to Fen for 4h/day, 5 days a week for 90 days by using Flow Past Dynamic Nose only Inhalation Chamber. Results Fen exposed rats showed a significant increase in enzymatic activities of lactate dehydrogenase (LDH), acid phosphatase (ACP), alkaline phosphatase (ALP) and γ-glutamyl transferase (γ-GT) which are considered as biochemical indicators of pulmonary damage. The concomitant histopathological examination of Fen exposed rats' lung revealed inflammatory changes viz., influx of mononuclear cells admixed with a few giant cells in alveolar lumen, hypetrophied bronchiolar and alveolar epithelial lining cells and presence of edematous fluid in alveolar lumen alongwith congested parenchymatous blood vessels. Conclusion These results for the first time indicate the pulmonary toxic effects of a commonly used formulated Fen preparation by using rat model and nose only inhalation as the route of exposure.

关键词： Animals Behavior, Animal Body Weight Inhalation Exposure Insecticides Lung Male Nitriles Nose Organ Size Pyrethrins Rats Rats, Wistar

Buckling analysis of planar linear uniform deployable structures consisting of scissor-like element in space under compression

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Science China(Technological Sciences) 2021年第3期64卷 493-507页

作者： LI Bo WANG SanMin TAN u-Xuan School of Mechanical and Precision Instrument Engineering Xi’an University of TechnologyXi’an 710048China Department of Engineering Product Development Singapore University of Technology and DesignSingapore 487372Singapore School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China

This paper comprehensively investigates the buckling load and the stability of a planar linear array deployable structure composed of scissor-like element(SLE)under *** present,the researches on deployable structure are mainly focused on configuration design and dynamics characteristics of the mechanisms,but less on structural *** fact,when the external load exceeds the structural critical load value,the deployable structure will be permanently deformed or even collapse directly and no longer have any bearing *** address this issue,a new stability model is derived using linear elastic analysis method and substructure method to evaluate the buckling characteristics of the deployable structure with n SLEs when it is carried out in space,which can accurately obtain the structural instability load and can be used quantitatively to optimize the structure for making it have the most stable *** addition,the effects of the number of elements,the length,material properties and flexibility of the bar,and the deployment degree on the buckling of the scissor deployable structure are investigated,and the results of the theoretical analysis are compared with simulation and analytical results,respectively,confirming that the proposed stability model not only is able to effectively predict the structural instability load but also determine which part of the deployable structure is *** can be concluded that the stability of the deployable structure gradually decreases with the increase of the number of elements or the bar *** the calculation process,the critical load of each sub-element should be considered,and the minimum value of the critical loads of all subunits can be regarded as the instability load of the whole structure.

关键词： deployable structure stability analysis buckling load sub structure linear array simulation

Estimation of Rheological Properties of RAP Binder

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Journal of Wuhan university of Technology(Materials Science) 2010年第5期25卷 866-870页

作者：马涛 HuSSAIN u Bahia School of Transportation Southeast University Nanjing 210096 China Department of Civil and Environmental Engineering University of Wisconsin-Madison 2205 Engineering Hall Madison WI 53706 USA

The low-temperature rheological properties of binders in the recycled asphalt pavement （RAP） material without the damaging effects of solvent extractions were analyzed. The developed procedure is based on testing of bitumen-RAP mortars produced by mixing the fresh （virgin） binder with RAP material smaller than # 8 sieve. Different mortars were prepared, containing RAP material passing the #8 sieve and 15% by weight of fresh binder. Low temperature properties of these mortars were investigated by using the bending beam rheometer （BBR） test procedure that is specially modified for testing of the RAP mortars. The modification involved the development of a new kind of mold and different testing parameters. The RAP material used in the experimental study were both extracted from real reclaimed pavement and prepared in the laboratory, by aging binder through repeated PAV cycles. The results indicate the new procedure can capture the effect of aged properties of bitumen in the RAP and can be used to estimate the PG low temperature grade of the blended binder. Although data is limited in size, the modification of the BBR appears to be simple and provide repeatable data.

关键词： RAP binder rheological properties aging bending beam rheometer

Generalized Weighted Morrey Estimates for Marcinkiewicz Integrals with Rough Kernel Associated with Schrodinger Operator and Their Commutators

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Chinese Annals of Mathematics,Series B 2020年第1期41卷 77-98页

作者： Ferit GuRBuZ Faculty of Education Department of Mathematics EducationHakkari UniversityHakkari 30000Turkey

Let L =-△+V(x) be a Schrodinger operator, where △ is the Laplacian on R^n,while nonnegative potential V(x) belonging to the reverse Holder class. The aim of this paper is to give generalized weighted Morrey estimates for the boundedness of Marcinkiewicz integrals with rough kernel associated with Schrodinger operator and their ***, the boundedness of the commutator operators formed by BMO functions and Marcinkiewicz integrals with rough kernel associated with Schrodinger operators is discussed on the generalized weighted Morrey spaces. As its special cases, the corresponding results of Marcinkiewicz integrals with rough kernel associated with Schrodinger operator and their commutators have been deduced, respectively. Also, Marcinkiewicz integral operators, rough Hardy-Littlewood(H-L for short) maximal operators, Bochner-Riesz means and parametric Marcinkiewicz integral operators which satisfy the conditions of our main results can be considered as some examples.

关键词： Marcinkiewicz operator Rough kernel Schrodinger operator generalized weighted Morrey space Commutator BMO

Sandy grassland blowouts in Hulunbuir, northeast China: geomorphology, distribution, and causes

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Progress in Natural Science:Materials International 2007年第1期17卷 68-73页

作者： ZHANG Altan MunkhDalai u Hurlee Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085China　Bureau of Land and Resources of Hulunbuir CityHulunbuir 021008China Primary Education College of Hulunbuir university Hulunbuir 021000 China

A sandy grassland blowout consists of an aeolian depression formed in top soil and the underlying sand deposit underlie, and the adjoining redeposit of sand derived from the depression. Research based on field survey and topographic mapping combined with aerophotograph interpretation reveals that: (1) All the three sand land tracts in Hulunbuir Grasslands are composed of blowout depressions and adjoining dunes, with interlaying remnants of sandy grasslands as background; (2) blowout depressions and their adjoining dunes can be classified according to their morphometric characteristics, development stages, and initiating factors; (3) blowouts develop mostly in the upper parts of sidelong aweather and sunward slopes inclining southwestward when west wind prevails; (4) initiation of blowouts is closely related with the coupling of extreme droughts and wide spread intense human disturbance to the fragile topsoil layer. The investigations indicate that key factors to prevent desertification are to protect grassland vegetation and topsoil.

关键词： Hulunbuir sandy grassland blowouts desertification.

Epithelial restitution and wound healing in inflammatory bowel disease

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World Journal of Gastroenterology 2008年第3期14卷 348-353页

作者： Andreas Sturm Axel u Dignass Department of Gastroenterology and Hepatology Charité-Campus Virchow Clinic Berlin Germany Department of Gastroenterology Hepatology Oncology and Metabolic Diseases Markus-Krankenhaus Frankfurt/Main Germany

Inflammatory bowel disease is characterized by a chronic inflammation of the intestinal mucosa. The mucosal epithelium of the alimentary tract constitutes a key element of the mucosal barrier to a broad spectrum of deleterious substances present within the intestinal lumen including bacterial microorganisms, various dietary factors, gastrointestinal secretory products and drugs. In addition, this mucosal barrier can be disturbed in the course of various intestinal disorders including inflammatory bowel diseases. Fortunately, the integrity of the gastrointestinal surface epithelium is rapidly reestablished even after extensive destruction. Rapid resealing of the epithelial barrier following injuries is accomplished by a process termed epithelial restitution, followed by more delayed mechanisms of epithelial wound healing including increased epithelial cell proliferation and epithelial cell differentiation. Restitution of the intestinal surface epithelium is modulated by a range of highly divergent factors among them a broad spectrum of structurally distinct regulatory peptides, variously described as growth factors or cytokines. Several regulatory peptide factors act from the basolateral site of the epithelial surface and enhance epithelial cell restitution through TGF-13-dependent pathways. In contrast, members of the trefoil factor family （TFF peptides） appear to stimulate epithelial restitution in conjunction with mucin glycoproteins through a TGF-13-independent mechanism from the apical site of the intestinal epithelium. In addition, a number of other peptide molecules like extracellular matrix factors and blood clotting factors and also non- peptide molecules including phospholipids~ short-chain fatty acids （SCFA）, adenine nucleotides, trace elements and pharmacological agents modulate intestinal epithelial repair mechanisms. Repeated damage and injury of the intestinal surface are key features of various intestinal disorders including inflammatory bowel disease

关键词： Intestines Wound healing Inflammation Restitution

Study of K^(*)(892)^(0)andФ(1020)meson production in proton–proton and Pb–Pb collisions at√S_(NN)=2.76 TeV

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Communications in Theoretical Physics 2021年第2期73卷 89-95页

作者： Y Ali M Ahmed A Arif Q Ali u Tabassam u Rubab M Suleymanov Department of Physics COMSATS UniversityPark RoadIslamabad44000Pakistan Institute for Physical Problems Baku Suate UniversityBakuAZ 1000Azrbajan

In this paper,we describe a study of charged particle yield as a function of pT for K^(*)(892)0 and phgr(1020)mesons in proton–proton(pp)and Pb–Pb collisions at√S_(NN)=2.76 TeV in the central rapidity region of|y|mportant ratio,the nuclear modification factor,to study the effects of the medium in the most central region,i.e.0%–5%*** data simulation,we used the EPOS-LHC and EPOS-1.99 *** check the validity of these models'simulations,we compared the data obtained from these Monte Carlo simulation programs with ALICE experimental data for√S_(NN)=2.76 *** was concluded that the models'predictions for the phgr-meson in pp and for the most central Pb-Pb collisions disagreed with the ALICE data,and that the difference increased with *** may be connected with the essential role of collective parton behaviors which could not have been taken into account by the *** K^(*)0 mesons,both programs gave almost the same predictions,and with pT in the interval pT>3 GeV c^(−1),the predictions were very close to the experimental *** models gave higher predictions for the soft pT interval and lower predictions for the hard *** values of the RAA distributions were lower than unity and both models were very close to the ALICE *** is very interesting that the models were not able to describe the pT distributions,but they gave good predictions for their *** may possibly be due to parton collective *** observed some additional suppression of K^(*)0 at low values of pT with respect to phgr-mesons,which may be related to the role of the masses of the particles in soft *** rising trend for R_(AA)in the region from pT=10 GeV c^(−1)to 20 GeV c^(−1) observed by the ALICE experiment was absent for theФ-mesons.

关键词： Quark Gluon Plasma EPOS-LHC nuclear modification factor

Subwavelength hybrid plasmonic structures for nonlinear nanophotonics

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Light(Science & Applications) 2021年第3期10卷 307-309页

作者： Ann-Katrin u.Michel Optical Materials Engineering Laboratory Department of Mechanical and Process EngineeringETH ZurichZurichSwitzerland

Plasmonic structures made of a semiconductor-insulator-metal hybrid provide efficient routes for second-harmonic and sum-frequency generation in sub-micrometer structures,which ultimately may boost on-chip integrated ... 详细信息

关键词： structures nonlinear plasmon