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50 Years Experience of the *** Electric Welding Institute in Field of Electron Beam Welding

稀有金属材料与工程 2011年第S4期40卷 6-13页

作者： o.K.Nazarenko V.m.Nesterenkov E.o.Paton Electric Welding Institute of the NAS of Ukraine

Studying the possibilities of electron beam welding (EBW) and the principles of construction of equipment for electron beam welding,led by academician Boris Evgenyevich Paton,began at the *** Electric Welding Institute (PWI) in *** resulted in development of the first laboratory-scale plant and welding of different small *** year later the method of electron beam welding turned out to be in great demand:in nuclear power engineering,in production of electric vacuum devices and liquid-fuel rocket *** 1961-1962 owing to effective coordination of work performed at government level,the first production machines for electron beam welding were put into operation at a number of branch *** the next few years,application of electron beam welding became wider,first of all in the above mentioned industries,and simultaneously electron beam welding began to be accepted by aircraft and power engineering *** 1960-s PWI organized in Ukraine full-scale production of power units,developed by it (guns,power sources and control systems) on the basis of Sumy Factory of Electron microscopes.72 complete sets of power source units of SP-30 type (25 kV,500 mА),330 complete sets of U-250А (30 kV,450 mА),320 complete sets of ELA-60 (60 kV,250,500 and 1000 mА) and ELA-120 (120 kV,1000 mА) were manufactured in different periods of *** october 16th 1969 the first test of electron beam welding and cutting of metals was carried out in ?Soyuz-6? spaceship,that practically initiated the space *** was performed in Vulkan unit developed by *** that in space X-radiation and difficulties with high-voltage insulation could eliminate the possibility of electron beam application,low accelerating voltage (not higher than 8 kV) was used.

关键词： electron beam welding Paton Electric Welding Institute technology equipment material engineering

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Control of a Two-wheeled machine with Two-directions Handling mechanism Using PID and PD-FLC Algorithms

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International Journal of Automation and computing 2019年第4期16卷 511-533页

作者： Khaled m. Goher Sulaiman o. Fadlallah School of Engineering University of Lincoln Lincoln LN6 7TS UK mechanical Engineering Department Auckland University of Technology Auckland 1142 New Zealand

This paper presents a novel five degrees of freedom (DoF) two-wheeled robotic machine (TWRm) that delivers solutions for both industrial and service robotic applications by enlarging the vehicle′s workspace and increasing its flexibility. Designing a two-wheeled robot with five degrees of freedom creates a high challenge for the control, therefore the modelling and design of such robot should be precise with a uniform distribution of mass over the robot and the actuators. By employing the Lagrangian modelling approach, the TWRm′s mathematical model is derived and simulated in matlab/Simulink?. For stabilizing the system′s highly nonlinear model, two control approaches were developed and implemented: proportional-integral-derivative (PID) and fuzzy logic control (FLC) strategies. Considering multiple scenarios with different initial conditions, the proposed control strategies′ performance has been assessed.

关键词： Two-wheeled inverted pendulum (IP) with two direction handling Lagrangian formulation proportional-integral-derivative (PID) fuzzy logic control (FLC) under-actuated systems

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Chemokines and Chemokine Receptors as Novel Therapeutic Targets in Rheumatoid Arthritis (RA):Inhibitory Effects of Traditional Chinese medicinal Components

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Cellular & molecular Immunology 2004年第5期1卷 336-342页

作者： XinChen JoostJ.oppenheim o.m.ZackHoward BasicResearchProgram SAIC-FrederickIncUSA. LaboratoryofmolecularImmunoregulation CenterforCancerResearchNationalCancerInstitute-FrederickFrederickMaryland21702-1201USA.

Chemokines belong to a large family of inflammatory cytokines responsible for migration and accumulation of leukocytes at inflammatory *** the past decade,accumulating evidence indicated a crucial role for chemokines and chemokine receptors in the pathophysiology of rheumatoid arthritis(RA).RA is a chronic autoimmune disease in which the synovial tissue is heavily infiltrated by *** play an important role in the infiltration,localization,retention of infiltrating leukocytes and generation of ectopic germinal centers in the inflamed *** evidence also suggests that identification of inhibitors directly targeting chemokines or their receptors may provide a novel therapeutic strategy in *** Chinese medicines(TCms) have a long history in the treatment of inflammatory joint *** basis for the clinical benefits of TCm remains largely *** studies have led to the identification of numerous novel chemokine/chemokine receptor inhibitors present in anti-inflammatory *** of these inhibitors were previously reported by other researchers to have anti-arthritic effect,which may be attributable,at least in part,to their inhibitory effect on chemokine and/or chemokine ***,identification of agents capable of targeting chemokine/chemokine receptor interactions has suggested a mechanism of action for several TCm components and provided a means of identifying additional anti-RA ***,this approach may lead to the discovery of new inhibitors of chemokines or chemokine receptors that can be used to treat diseases associated with inappropriately overactive chemokine mediated inflammatory *** & molecular Immunology.2004;1(5):336-342.

关键词： chemokine receptor rheumatoid arthritis traditional Chinese medicine

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Interlayer distance effects on absorption coefficient and refraction index change in p-type double-δ-doped GaAs quantum wells

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Chinese Physics B 2019年第12期28卷 186-190页

作者： H Noverola-Gamas L m Gaggero-Sager o oubram Instituto de Investigaciones en Ciencias Básicas y Aplicadas Universidad Autónoma del Estado de Morelos MorelosCuernavaca 62209Mexico Division Academica de Ingeniería y Arquitectura Universidad Juárez Autonoma de TabascoCunduacan 8660Mexico Centro de Investigación en Ingeniería y Ciencias Aplicadas Universidad Autónoma del Estado de MorelosCuernavaca 62209Mexico Facultad de Ciencias Químicas e Ingeniería Universidad Autónoma del Estado de MorelosCuernavaca 62209Mexico

In the framework of the Thomas–Fermi(TF) approach, a model for the p-type double-δ-doped(DDD) system in Ga As is presented. This model, unlike other works in the literature, takes into account that the Poisson equation associated with the system is nonlinear. The electronic structure is calculated for heavy and light holes. The changes in the electronic structure result of the distance d between the doped layers are studied. In particular, the relative absorption coefficient as well as the relative refractive index change is calculated as a function of the incident photon energy for heavy holes. The effect of the interlayer distance exhibits, in the absorption coefficient, a red shift of the peak position and a decrease in amplitude when the distance increases. In addition, the relative refractive index change node has a red shift as well as the interlayer distance increases. The calculations show that the effect of the separation between layers has a greater influence on the linear terms. These results are very important for theoretical calculations and engineering of optical and electronic devices based in δ-doped Ga As.

关键词： double delta-doping p-type GaAs layers electronic structure Thomas–Fermi approach nonlinear optical properties

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A theoretical investigation of the band alignment of type-I direct band gap dilute nitride phosphide alloy of GaN_xAs_yP_(1-x-y)/GaP quantum wells on GaP substrates

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Chinese Physics B 2014年第7期23卷 640-644页

作者： o L nsal B Gnül m Temiz Department of Engineering Physics University of Gaziantep

The GaP-based dilute nitride direct band gap material Ga（NAsP） is gaining importance due to the monolithic integra- tion of laser diodes on Si microprocessors. The major advantage of this newly proposed laser material system is the small lattice mismatch between GaP and Si. However, the large threshold current density of these promising laser diodes on Si substrates shows that the carrier leakage plays an important role in Ga（NAsP）/GaP QW lasers. Therefore, it is necessary to investigate the band alignment in this laser material system. In this paper, we present a theoretical investigation to optimize the band alignment of type-I direct band gap GaNxAsyP1-x-y/GaP QWs on GaP substrates. We examine the effect of nitrogen （N） concentration on the band offset ratios and band offset energies. We also provide a comparison of the band alignment of type-I direct band gap GaNxAsyP1-x-y/GaP QWs with that of the GaNxAsyP1-x-y/Al2Ga1-2P QWs on GaP substrates. our theoretical calculations indicate that the incorporations of N into the well and AI into the barrier improve the band alignment compared to that of the GaAsP/GaP QW laser heterostructures.

关键词： quantum well band alignment carrier confinement dilute nitride phosphide alloy

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Generalized quantum mechanical two-Coulomb-center problem (Demkov problem)

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Chinese Physics B 2013年第9期22卷 245-251页

作者： A.m.Puchkov A.V.Kozedub E.o.Bodnia Theoretical Department Institute of PhysicsSt. Petersburg State University Department of Computational Physics Faculty of PhysicsSt. Petersburg State University

We present a new exactly solvable quantum problem for which the Schrtidinger equation allows for separation of variables in oblate spheroidal coordinates. Namely, this is the quantum mechanical two-Coulomb-center problem for the case of an imaginary intercenter parameter and complex conjugate charges are considered. Since the potential is defined by the two-sheeted mapping whose singularities are concentrated on a circle rather than at separate points, there arise additional possibilities in the choice of boundary conditions. A detailed classification of the various types of boundary-value problems is given. The quasi-radial equation leads to a new type of boundary value problem which has never been considered before. Results of the numerical calculations, which allow conclusions to be drawn about the structure of the energy spectrum, are shown. Possible physical applications are discussed.

关键词： two-Coulomb-center problem potential models

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Simulation of the spatio-temporal evolution of the electron energy distribution function in a pulsed hollow-cathode discharge

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Plasma Science and Technology 2023年第3期25卷 87-94页

作者： N A ASHURBEKoV K o ImINoV K m RABADANoV G S SHAKHSINoV m Z ZAKARYAEVA m B KURBANGADZHIEVA Dagestan State University Department of Physics Harbin Institute of Technology Institute of Physics Dagestan Federal Research CenterRussian Academy of Sciences

This article presents the 2D simulation results of a nanosecond pulsed hollow cathode discharge obtained through a combination of fluid and kinetic *** spatio-temporal evolution of the electron energy distribution function(EEDF)of the plasma column and electrical characteristics of the nanosecond pulsed hollow cathode discharge at a gas pressure of 5 Torr are *** results show that the discharge development starts with the formation of an ionization front at the anode *** ionization front splits into two parts in the cathode cavity while propagating along its lateral *** ionization front formation leads to an increase in the fast isotropic EEDF component at its front,as well as in the anisotropic EEDF *** accelerated electrons enter the cathode cavity,which significantly contributes to the formation of the highenergy EEDF component and EEDF anisotropy.

关键词： pulsed nanosecond discharge electron energy distribution fuinction hollow cathode electron kinetics gas discharge

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Characterization of refractory behaviour of complex gold/silver ore by diagnostic leaching

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中国有色金属学会会刊：英文版 2009年第3期19卷 707-713页

作者： o. CELEP . ALP H. DEVEC m. VICIL mining Engineering Department Karadeniz Technical University Geology Engineering Department Karadeniz Technical University

The amenability of a refractory ore to the extraction of gold and silver by cyanide leaching was investigated. Diagnostic leaching tests were also performed to shed light on the refractory characteristics of ore. The leaching tests show that the extraction of gold and silver is consistently low, i.e. ≤47% and ≤19.2%, respectively, over a leaching period of 24 h. Even fine grinding (e.g. m) does not improve the recovery of gold and silver. Diagnostic leaching approach provides information into the cause of the refractoriness of the ore. The findings suggest that the refractoriness is induced by the dissemination and encapsulation of the very fine gold and silver particles largely in the carbonates, oxides and sulfides and, to a small extent, with silicates present in the ore matrix. These findings highlight the practical importance of diagnostic leaching for the understanding of the refractory characteristic of such an ore and for the identification of possible pretreatment options to overcome its refractoriness prior to cyanide leaching.

关键词：氰化浸出银矿石黄金诊断行为表征浸出试验硅酸盐矿石

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Burrow morphology of Uca uruguayensis and Uca leptodactylus(Decapoda:ocypodidae)from a subtropical mangrove forest in the western Atlantic

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Integrative Zoology 2013年第3期8卷 307-314页

作者： Glauco B.o.mACHADo João B.L.GUSmÃo-JUNIoR Tânia m.CoSTA Campus Experimental do Litoral Paulista UNESPSão VicenteSão PauloBrazil

The continuous excavation of burrows by fiddler crabs generates bioturbation in the sediment,which can be estimated from burrow *** aim of the present study was to describe the burrow morphology of Uca uruguayensis and *** and its relationship with demography of resident individuals and to estimate the level of bioturbation in the sediment generated by each *** all individuals from each of the 2 species,sex was determined and the carapace width(CW;mm)*** were characterized according to burrow diameter(BD;mm),maximum burrow depth(mBD;mm)and burrow volume(BV;cm^(3)).The density of each species in the study area was also *** both species,the males were larger and occupied burrows with higher BV compared to *** between sexes in relation to the burrow characteristics might reflect sexual dimorphism within the group and are probably related to the fact that males use the burrows for *** and BV showed significant positive relationships with the size of resident *** amount of sediment removed per burrow was estimated from mean BV:10.78 cm^(3)of sediment/burrow for *** and 12.38 cm^(3)of sediment/burrow for *** the density and depth differences between the 2 species,the similarity in burrow volume suggests that *** and *** present the same importance in terms of the bioturbation *** morphology is highly associated with characteristics of the occupant,although extrinsic factors should also be considered,and its description can provide estimates on the bioturbation generated by Uca species in mangrove forests.

关键词： bioturbation burrow structure crab burrowing fiddler crab

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Discrete Simulation of Flexible Plate Structure Using State-Space Formulation

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系统仿真学报 2008年第19期20卷 5141-5146页

作者： S. md. Salleh m. o. Tokhi Department of Automatic Control and System Engineering The University of Sheffield Sheffield S3 1JD U. Kingdom Faeulty of mechanical and manufacturing Engineering University of Tun Hussein Onn Malaysia 86400 Johor Malaysia

This paper presents the development of dynamic simulation of a flexible plate structure with various boundary conditions. A flexible square plate is considered. A finite-difference method is used to discretise the governing partial differential equation formulation describing its dynamic behaviour. The model thus developed has been validated against characteristic parameters of the plate. The model thus developed is further formulated using discrete state-space representation, to allow easy and fast implementation for simulating the dynamic behaviour of the plate with various boundary conditions. The simulation algorithm thus developed is validated, and accurate results with representation of the first five modes of vibration of the plate have been achieved. The algorithm thus developed is used in subsequent research work as a platform for development and verification of suitable control strategies for vibration suppression of flexible plate structures.

关键词：复杂系统模拟技术平面结构分析方法系统结构

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