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The Dual Spaces of Sets of Difference Sequences of Order m and Matrix Transformations

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Acta Mathematica Sinica,English Series 2007年第3期23卷 521-532页

作者： eberhard malkowsky M.MURSALEEN Suthep SUANTAI Department of Mathematics University of GiessenArndtstrasse 2D-35392 GiessenGermany and Department of MathematicsFaculty of Sciences and MathematicsUniversity of NiViegradska 3318000 NiSerbia and Montenegro Department of Mathematics Aligarh Muslim UniversityAligarh 202002India and Department of MathematicsFaculty of Science Department of Mathematics Chiang Mai UniversityChiang MaiThailand

Let p = （pk）k=0^∞ be a bounded sequence of positive reals, m C N and u be s sequence of nonzero terms. If x = （xk）k=0^∞ is any sequence of complex numbers we write Δ（m）x for the sequence of the m th order differences of x and Δu^（m）X = {x=（x）k=0^∞ uΔ（m）x ∈ X} for any set X of sequences. We determine the α-, β- and γ-duals of the sets Δμ^（m）X for X=co（p）,c（p）,l∞（p） and characterize some matrix transformations between these spaces Δ^（m）X.

关键词： difference sequences dual spaces matrix transformations

Modelling of particle layer detachment—Role of transient kinetic effects

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Particuology 2009年第1期7卷 45-51页

作者： eberhard Schmidt Faculty D-Safety Engineering/Environmental Protection University of WuppertalBuilding FFRainer-Gruenter-StrasseD-42119 WuppertalGermany

Particle layers tend to build up on wails in many filtration and separation processes, calling for periodic removal in order to keep the apparatus running. Important factors are the adhesion of the layer on the substrate and the cohesion of the particles in the layer. Models describing such layer detachment generally assume constant and homogeneous conditions for the forces acting on the layer. But in reality detachment is extremely non-stationary concerning place and time, primarily due to changing conditions of the detaching forces on the one hand and changes in the particle layer morphology on the other. This paper describes a model and a simulation based on this model considering such transient kinetic effects, for which some computing results are presented and discussed.

关键词： Adhesive forces Filter cleanability Dust cake discharge Patchy cleaning

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Nucleon excitations

Chinese Physics C 2010年第9期34卷 1241-1246页

作者： eberhard Klempt Helmholtz-Institut für Strahlen- und Kernphysik der Universitt Bonn Nuβallee 14-16

The mass pattern of nucleon and Δ resonances is compared with predictions based on quark models,the Skyrme model,AdS/QCD,and the conjecture of chiral symmetry restoration.

关键词： baryon resonances AdS/QCD quark models chiral symmetry

Quantification of particle separation using electrostatically charged spray mist in a dust chamber

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Particuology 2021年第5期19卷 92-98页

作者： Marcel Zillgitt eberhard Schmidt Institute of Particle Technology Rainer Gruenter StraBeBuilding FFCampusFreudenbergBergische Universitat Wuppertal42119 WuppertalGermany

In order to improve the efficiency of reducing fine dust emissions from diffuse sources,the commonly used water mist can be electrostatically ***,the attraction between particles and droplets increases due to electrostatic field *** the experimental investigations carried out,an electrostatic two-fluid nozzle was used to generate a charged spray mist according to the principle of charging by *** a chamber,dispersed dust was precipitated with the spray mist,while detecting the laser light *** means of comparative measurements it could be shown that faster sedimentation and separation takes place through electrostatic *** variations regarding the use of compressed air and water were investigated and the sedimentation time of the particle-droplet mixture in the chamber was shown.A size distribution was then calculated from the laser light attenuation,which shows that the proportion of small particles decreases with spray ***,the influence of the polarity of droplets and solid particles on the reduction measure was determined.

关键词： Dust separation Spray mist Electrostatic Dust chamber Laser light attenuation Charging by induction

Adaptive nonlinear model predictive control design of a flexible-link manipulator with uncertain parameters

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Acta Mechanica Sinica 2017年第3期33卷 529-542页

作者： Fabian Schnelle Peter eberhard Institute of Engineering and Computational Mechanics University of Stuttgart

This paper presents a novel adaptive nonlinear model predictive control design for trajectory tracking of flexible-link manipulators consisting of feedback linearization, linear model predictive control, and unscented Kalman filtering. Reducing the nonlinear system to a linear system by feedback linearization simplifies the optimization problem of the model predictive controller significantly, which, however, is no longer linear in the presence of parameter uncertainties and can potentially lead to an undesired dynamical behaviour. An unscented Kalman filter is used to approximate the dynamics of the prediction model by an online parameter estimation, which leads to an adaptation of the optimization problem in each time step and thus to a better prediction and an improved input action. Finally, a detailed fuzzy-arithmetic analysis is performed in order to quantify the effect of the uncertainties on the control structure and to derive robustness assessments. The control structure is applied to a serial manipulator with two flexible links containing uncertain model parameters and acting in three-dimensional space.

关键词： Model predictive control Feedback linearization Unscented Kalman filter Flexible-link manipulator Fuzzy-arithmetical analysis

Application of dynamic image analysis to the optical characterisation of fibrous bulk material

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Particuology 2024年第7期90卷 51-60页

作者： Johannes Lunewski eberhard Schmidt Institute of Particle Technology University of WuppertalGermany

Dynamic image analysis provides an automated evaluation method to determine the size and shape of multiple particles. This method represents a common application for ordinary bulk material. The latest draft of ISO 13322–2:2021 describes the state of the art, but lacks instructions for handling fibrous bulk material. Interlocking fibres complicate the measurement conditions and require a disentanglement of fibrous samples during a pre-dispersion step. A further error source includes the fibre orientation inside the measurement zone of the device. If the thresholding algorithm fails to differentiate between the fibre projection area and the background, a subsequent image optimisation solves the problem. This article addresses the mentioned problems by analysing cotton cellulose and polyacrylonitrile fibres. Besides the execution of a pre-dispersion step, the experiments compare the discrepancies between dry and wet dispersion. Here, the software packages PAQXOS and ImageJ perform the image evaluation. In this case, the wet dispersion setup with a subsequent image evaluation by ImageJ provides comprehensible results.

关键词： Bootstrap method Dynamic image analysis Fibre diameter Fibre length distribution Natural fibres Synthetic fibres

Hepatitis B virus-induced oncogenesis

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World Journal of Gastroenterology 2007年第1期13卷 74-81页

作者： Joachim Lupberger eberhard Hildt Department of Internal Medicine II Hugstetter Str. 55 D-79106 Freiburg Germany

Hepatocellular carcinoma (HCC) is one of the most com- mon cancers in the world with an annual incidence of more than 500 000 in the year 2000. Its incidence is rising in many countries. Recently, it has been estimated that about 53% of HCC cases in the world are related to hepatitis B virus (HBV). The epidemiological association of HBV with HCC is well established. In recent studies, it was revealed that HBsAg carriers have a 25-37 times increased risk of developing HCC as compared to non-infected people. At present, HBV-associated carcinogenesis can be seen as a multi-factorial process that includes both direct and indirect mechanisms that might act synergistically. The integration of HBV DNA into the host genome occurs at early steps of clonal tumor expansion. The integration has been shown in a number of cases to affect a variety of cancer- related genes and to exert insertional mutagenesis. The permanent liver inflammation, induced by the immune response, resulting in a degeneration and regeneration process confers to the accumulation of critical mutations in the host genome. In addition to this, the regulatory proteins HBx and the PreS2 activators that can be encoded by the integrate exert a tumor promoter-like function resulting in positive selection of cells producing a functional regulatory protein. Gene expression profiling and proteomic techniques may help to characterize the molecular mechanisms driving HBV-associated carcino- genesis, and thus potentially identify new strategies in diagnosis and therapy.

关键词： Hepatitis B virus Hepatocellular carcinoma Regulatory proteins Signal transduction

Testosterone deficiency：a historical perspective

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Asian Journal of Andrology 2014年第2期16卷 161-168,I0006页

作者： eberhard Nieschlag Susan Nieschlag Center of Reproductive Medicine and Andrology University Hospital of M(Jnster MOnster Germany Center of Excellence in Genomic Medicine Research King Abdulaziz University Jeddah Saudi Arabia.

The biological effects of the testes and testosterone are known since antiquity. Aristotle knew the effects of castration and his hypothesis on fertilization is one of the first scientific encounters in reproductive biology. Over centuries, castration has been performed as punishment and to produce obedient slaves, but also to preserve the soprano voices of prepubertal boys. The Chinese imperial （and other oriental） courts employed castrates as overseers in harems who often obtained high-ranking political positions. The era of testis transplantation and organotherapy was initiated by John Hunter in London who transplanted testes into capons in 1786. The intention of his experiments was to prove the ＇vital principle＇ as the basis for modern transplantation medicine, but Hunter did not consider endocrine aspects. Arnold Adolph Berthold postulated internal secretion from his testicular transplantation experiments in 1849 in Gottingen and is thus considered the father of endocrinology. Following his observations, testicular preparations were used for therapy, popularized by self-experiments by Charles-Edouard Brown-Sequard in Paris （1889）, which can at best have placebo effects. In the 1920s Sergio Voronoff transplanted testes from animals to men, but their effectiveness was disproved. Today testicular transplantation is being refined by stem cell research and germ cell transplantation. Modern androgen therapy started in 1935 when Enrest Lacquer isolated testosterone from bull testes in Amsterdam. In the same year testosterone was chemically synthesized independently by Adolf Butenandt in G6ttingen and Leopold Ruzicka in Basel. Since testosterone was ineffective orally it was either compressed into subcutaneous pellets or was used orally as 17α-methyl testosterone, now obsolete because of liver toxicity. The early phases of testosterone treatment coincide with the first description of the most prominent syndromes of hypogonadism by Klinefelter, by Kallmann, DelCastillo

关键词： castration testosteron testosterone deficiency

Thermal Reversion of Plant Phytochromes

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Molecular Plant 2020年第3期13卷 386-397页

作者： Cornelia Klose Ferenc Nagy eberhard Schafer Institute of Biology II University of Freiburg79104 FreiburgGermany Institute of Plant Biology Biological Research CentreTemesvari krt.626726 SzegedHungary

Phytochromes are red/far-red reversible photoreceptors essential for plant growth and *** signaling is mediated by the physiologically active far-red-absorbing Pfr form that can be inactivated to the red-absorbing Pr ground state by light-dependent photoconversion or by light-independent thermal reversion,also termed dark *** the term“dark reversion”is justified by historical reasons and frequently used in the literature,“thermal reversion”more appropriately describes the process of light-independent but temperature-regulated Pfr relaxation that not only occurs in darkness but also in light and is used throughout the *** reversion is a critical parameter for the light sensitivity of phytochrome-mediated responses and has been studied for decades,often resulting in contradictory *** reversion is an intrinsic property of the phytochrome molecules but can be modulated by intra-and intermolecular interactions,as well as biochemical modifications,such as *** this review,we outline the research history of phytochrome thermal reversion,highlighting important predictions that have been made before knowing the molecular *** further summarize and discuss recent findings about the molecular mechanisms regulating phytochrome thermal reversion and its functional roles in light and temperature sensing in plants.

关键词： phytochrome phyA phyB thermal reversion dark reversion in vivo spectroscopy