2,194 research outputs found
A digital twin framework for Industry 4.0 enabling next-gen manufacturing
Digital twins offer a framework to support the ever-rising demands in the fast-paced industrial evolution. This technology not only adds to the reliability of industrial processes but also offers an insight in to long-term behaviors and pattern during the aging of the industrial equipment. In this paper, a digital twin framework is presented to replicate the processes of a real production line for product assembly. The proposed work implements a digital/graphical replica of Festo Cyber Physical Factory (CPF) for Industry 4.0 (I4.0). The implemented system allows to schedule orders and specify product configuration which embodies the actions of CPF in digital world. In addition, the paper also presents a viable framework to interlink the physical system with the digital instance to offer extended services and a pathway towards realization of fully functional digital twins
DEVELOPMENT OF POLYRROLE THIN FILM BASED SOLID-CONTACT ION-SELECTIVE ELECTRODES FOR NITRATE AND NITRITE
Joint Research on Environmental Science and Technology for the Eart
Helminth eggs die-off and nutrients : human excreta storage experiment
Are the current practices of handling human excreta for agricultural purposes by farmers in Vietnam good enough?This study set up an excreta storage experiment to research how to inactivate Ascaris lumbricoides eggs and stillmaintain the nutrient value of human excreta
ULTRA-TRACE DETERMINATION OF IRIDIUM BY ETV/ICP-MS USING CHEMICAL MODIFIERS
Joint Research on Environmental Science and Technology for the Eart
INSIGHT INTO NANOPARTICLE CHARGING MECHANISM IN NONPOLAR SOLVENTS TO CONTROL THE FORMATION OF PT NANOPARTICLE MONOLAYERS BY ELECTROPHORETIC DEPOSITION
Electrophoretic deposition of nanoparticles is considered to be one of the convenient methods for preparation of ordered nanoparticle monolayers. By using a nonpolar suspension of nanoparticles, we can (a) limit the current between the electrodes; (b) reduce the changes in the composition and conductivity of the medium due to the generation of charged species near the electrodes; and (c) suppress electrochemical reactions at the electrodes. One of the important questions about understanding the principle mechanisms of electrophoretic deposition is to identify the origin of electric charge in nonpolar suspension from which the nanoparticles are deposited. We developed a simple model of nanoparticle charging and we explained how the amount of the charge carried by nanoparticles can affect the quality of deposited monolayers. For electrophoretic deposition, we used silicon substrates as electrodes and Pt nanoparticles in water-AOT-isooctane reverse micellar system as a suspension. We used the centrifugation of Pt in combination with DLS measurements for controlling the charge carried by nanoparticles. Prepared nanoparticle monolayers were analyzed by AFM, SEM and electrical measurements.
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PREPARATION AND CHARACTERIZATION OF LOW RESISTIVITY CuS FILMS USING SPRAY PYROLYSIS
CuS films were prepared by spray pyrolysis from solutions of (NH 2 ) 2 CS and CuCl 2 .2H 2 O mixed at ratios of 3:1, 4:1 and 5:1 on glass substrates heated at 160 to 240 o C. The deposition temperatures and pulsed regime of spray were controlled with the help of electronic equipments. The resistivity, phase composition, morphology, band gap energy and type of conductivity of the films were characterized using volt-ampere, XRD, SEM, optical absorption and Hall effect measurements. It was found that for all ratios of precursors the low resistivity of the films was stably obtained at substrate temperatures from 170 to 220 o C. Among them the lowest sheet resistivity of the films reached value of 8 ohm/sqr. The influences of deposition temperature and material ratio on characteristics of the spray deposited CuS films were discussed
CONTAMINATION BY ARSENIC AND LEAD IN RESIDENTS FROM VIETNAM
Joint Research on Environmental Science and Technology for the Eart
Bayesian inverse problems for recovering coefficients of two scale elliptic equations
We consider the Bayesian inverse homogenization problem of recovering the
locally periodic two scale coefficient of a two scale elliptic equation, given
limited noisy information on the solution. We consider both the uniform and the
Gaussian prior probability measures. We use the two scale homogenized equation
whose solution contains the solution of the homogenized equation which
describes the macroscopic behaviour, and the corrector which encodes the
microscopic behaviour. We approximate the posterior probability by a
probability measure determined by the solution of the two scale homogenized
equation. We show that the Hellinger distance of these measures converges to
zero when the microscale converges to zero, and establish an explicit
convergence rate when the solution of the two scale homogenized equation is
sufficiently regular. Sampling the posterior measure by Markov Chain Monte
Carlo (MCMC) method, instead of solving the two scale equation using fine mesh
for each proposal with extremely high cost, we can solve the macroscopic two
scale homogenized equation. Although this equation is posed in a high
dimensional tensorized domain, it can be solved with essentially optimal
complexity by the sparse tensor product finite element method, which reduces
the computational complexity of the MCMC sampling method substantially. We show
numerically that observations on the macrosopic behaviour alone are not
sufficient to infer the microstructure. We need also observations on the
corrector. Solving the two scale homogenized equation, we get both the solution
to the homogenized equation and the corrector. Thus our method is particularly
suitable for sampling the posterior measure of two scale coefficients
Noncommutative gravity: fuzzy sphere and others
Gravity on noncommutative analogues of compact spaces can give a finite mode
truncation of ordinary commutative gravity. We obtain the actions for gravity
on the noncommutative two-sphere and on the noncommutative in
terms of finite dimensional -matrices. The commutative large
limit is also discussed.Comment: LaTeX, 13 pages, section on CP^2 added + minor change
Theory of Exciton Recombination from the Magnetically Induced Wigner Crystal
We study the theory of itinerant-hole photoluminescence of two-dimensional
electron systems in the regime of the magnetically induced Wigner crystal. We
show that the exciton recombination transition develops structure related to
the presence of the Wigner crystal. The form of this structure depends strongly
on the separation between the photo-excited hole and the plane of the
two-dimensional electron gas. When is small compared to the magnetic
length, additional peaks appear in the spectrum due to the recombination of
exciton states with wavevectors equal to the reciprocal lattice vectors of the
crystal. For larger than the magnetic length, the exciton becomes strongly
confined to an interstitial site of the lattice, and the structure in the
spectrum reflects the short-range correlations of the Wigner crystal. We derive
expressions for the energies and the radiative lifetimes of the states
contributing to photoluminescence, and discuss how the results of our analysis
compare with experimental observations.Comment: 10 pages, no figures, uses Revtex and multicol.st
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