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61.
Quality control is an important and integral part to any microfabrication process. While the widths of features often can be easily assessed by light microscopy, the heights of the fabricated structures are more difficult to determine. Here, we present a rapid, accurate, and low-cost method to measure the heights of microfabricated structures during and after the fabrication process. This technique is based on white-light interferometry, which offers accuracy on the submicrometre scale. 相似文献
62.
Roberto Alicandro Marco Cicalese Antoine Gloria 《Archive for Rational Mechanics and Analysis》2011,200(3):881-943
This article is devoted to the study of the asymptotic behavior of a class of energies defined on stochastic lattices. Under
polynomial growth assumptions, we prove that the energy functionals Fe{F_\varepsilon} stored in the deformation of an e{{\varepsilon}}-scaling of a stochastic lattice Γ-converge to a continuous energy functional when e{{\varepsilon}} goes to zero. In particular, the limiting energy functional is of integral type, and deterministic if the lattice is ergodic.
We also generalize, to systems and nonlinear settings, well-known results on stochastic homogenization of discrete elliptic
equations. As an application of the main result, we prove the convergence of a discrete model for rubber towards the nonlinear
theory of continuum mechanics. We finally address some mechanical properties of the limiting models, such as frame-invariance,
isotropy and natural states. 相似文献
63.
Georgiana Dascalu Gloria Pompilian Bertrand Chazallon Valentin Nica Ovidiu Florin Caltun Silviu Gurlui Cristian Focsa 《Applied Physics A: Materials Science & Processing》2013,110(4):915-922
CoFe2O4 thin films with preferential texture structure, small grain size, and perpendicular magnetic anisotropy can be obtained by the pulsed laser deposition (PLD) technique. In this work, we studied the influence of the Fe3+ ions substitution by three elements from lanthanide group (Dy, La, and Gd) on the structural properties of the thin films. The samples were deposited by Nd:YAG laser (λ=532 nm, 10 ns) ablation of CoFe1.8RE0.2O4, (RE=Dy, La, Gd) targets at various substrate temperatures ranging from room temperature to 600 °C. The microstructure and chemical composition of the thin films were investigated by Raman spectroscopy, XRD, SEM-EDS, and ToF-SIMS. The XRD patterns and Raman spectra of the thin films indicated the formation of a single spinel structure. Thus, the desired substitution of the iron ions in the spinel lattice with the RE elements was achieved in the thin films, although in the bulk material, their presence determined the formation of a residual phase with a perovskite-type structure. 相似文献
64.
Narjès Bellamine-Ben Saoud Gloria Mark 《Computational & Mathematical Organization Theory》2007,13(2):113-146
In this paper, we investigate how complexity theory can benefit collaboration by applying an agent-based computer simulation
approach to a new form of synchronous real-time collaborative engineering design. Fieldwork was conducted with a space mission
design team during their actual design sessions, to collect data on their group conversations, team interdependencies, and
error monitoring and recovery practices. Based on the fieldwork analysis, an agent-based simulator was constructed. The simulation
shows how error recovery and monitoring is affected by the number of small group, or sidebar, conversations, and consequent
noise in the room environment. This simulation shows that it is possible to create a virtual environment with cooperating
agents interacting in a dynamic environment. This simulation approach is useful for identifying the best scenarios and eliminating
potential catastrophic combinations of parameters and values, where error recovery and workload in collaborative engineering
design could be significantly impacted. This approach is also useful for defining strategies for integrating solutions into
organizations.
Narjès Bellamine-Ben Saoud is an Associate Professor at the University of Tunis and Researcher at RIADI-GDL Laboratory, Tunisia. After Computer Science
engineering diploma (1993) of the ENSEEIHT of Toulouse, France, she received her PhD (1996), on groupware design applied to
the study of cooperation within a space project, from the University of Toulouse I, France. Her main research interests concern
studying complex systems particularly by modeling and simulating collaborative and socio-technical systems; developing Computer
Supported Collaborative Learning in tunisian primary schools; and Software Engineering. Her current reserach projects include
modeling and simulation of emergency rescue activities for large-scale accidents, modeling of epidemics and study of malaria,
simulation of collabration artifacts.
Gloria Mark is an Associate Professor in the Department of Informatics, University of California, Irvine. Dr. Mark received her Ph.D.
in Psychology from Columbia University in 1991. Prior to UCI, she was a Research Scientist at the GMD, in Bonn, Germany, a
visiting research scientist at the Boeing Company, and a research scientist at the Electronic Data Systems Center for Advanced
Research. Dr. Mark’s research focuses on the design and evaluation of collaborative systems. Her current projects include
studying worklife in the network-centric organization, multi-tasking of information workers, nomad workers, and a work in
a large-scale medical collaboratory. Dr. Mark is widely published in the fields of CSCW and HCI, is currently the program
co-chair for the ACM CSCW’06 conference and is on the editorial board of Computer Supported Cooperative Work: The Journal
of Collaborative Computing, and e-Service Qu@rterly. 相似文献
65.
Gloria E. Helfand 《Natural Resource Modeling》1993,7(3):203-217
Pollution standards in practice take many forms, such as measuring pollution per unit of output rather than just restricting pollution. This paper uses simulations to provide some evidence on the effects of these two forms of standards when firms vary. For the cases studied, it shows that a pollution standard can lead to higher profits, but a pollution-per-output standard leads to higher output and lower price; the overall efficiency effects are therefore ambiguous. 相似文献
66.
67.
Mario Bianchi Gloria Menchi Franco Francalanci Franco Piacenti Ugo Matteoli Piero Frediani Carlo Botteghi 《Journal of organometallic chemistry》1980,188(1):109-119
Saturated monocarboxylic acids up to C6, several bicarboxylic acids and some of the corresponding anhydrides are hydrogenated in the homogeneous phase with H4Ru4(CO)8(PBu3)4 as catalyst to give the corresponding alcohols (present among the reaction products as esters) or lactones at 100–200°C under a pressure of 100–200 atm of hydrogen. Anhydrides react at temperatures lower than those needed for acids. Esters are not reduced. Only δ-valerolactone is hydrogenated to 1,5-pentanediol. Ruthenium carbonyl carboxylates have been recovered at the end of the reaction and appear to be catalytically active intermediates. 相似文献
68.
69.
Let m be an integer, m 2 and set n = 2m. Let G be a non-cyclic group of order 2n admitting a cyclic subgroup of order n. We prove that G always admits a starter and so there exists a one–factorization of K2n admitting G as an automorphism group acting sharply transitively on vertices. For an arbitrary even n > 2 we also show the existence of a starter in the dicyclic group of order 2n.Research performed within the activity of INdAM–GNSAGA with the financial support of the Italian Ministry MIUR, project Strutture Geometriche, Combinatoria e loro Applicazioni 相似文献
70.
Four phenolic glycosides (1-4), including two new ones (3 and 4), have been isolated from the stems of Casearia multinervosa and identified as arbutin (1), 4-O-E-caffeoylarbutin (2), 4-O-E-coumaroylarbutin (3) and 4-O-E-feruloylarbutin (4), respectively. In addition, the two known phenolic glycosides (1 and 2) were also isolated from the leaves. Structures were elucidated on the basis of spectroscopic evidence. Compounds 1-4 were tested for cytotoxicity against the P388 mouse lympholytic cell line by an ATP Lite-M assay method and showed mild to moderate activity. 相似文献