4,060 research outputs found
Improvement of the guiding performances of near infrared organic/inorganic channel waveguides
New sol-gel derived organic/inorganic hybrid single mode waveguides devices
have been developed for telecommunication applications in the two near infrared
windows at 1310 and 1550 nm. The overall procedure of fabrication of these
devices is described and the refractive indices of the guiding, the buffer and
the protective layers are adjusted by a precise control of the materials'
composition. Due to the improvement of the composition of the guiding layer,
the attenuation losses are significantly decreased to 0.8 dB/cm and 2dB/cm at
respectively 1310 and 1550 nm
Commentary on Directive 2000/31/EC, art. 9, section 3:contracts concluded by electronic means, Concise European IT Law
Commentary on Directive 2000/31/EC, art. 9, section 3:contracts concluded by electronic means, Concise European IT Law
Damage spreading and coupling in Markov chains
In this paper, we relate the coupling of Markov chains, at the basis of
perfect sampling methods, with damage spreading, which captures the chaotic
nature of stochastic dynamics. For two-dimensional spin glasses and hard
spheres we point out that the obstacle to the application of perfect-sampling
schemes is posed by damage spreading rather than by the survey problem of the
entire configuration space. We find dynamical damage-spreading transitions
deeply inside the paramagnetic and liquid phases, and show that critical values
of the transition temperatures and densities depend on the coupling scheme. We
discuss our findings in the light of a classic proof that for arbitrary Monte
Carlo algorithms damage spreading can be avoided through non-Markovian coupling
schemes.Comment: 6 pages, 8 figure
Light-driven liquid crystalline nonlinear oscillator under optical periodic forcing
An all-optically driven strategy to govern a liquid crystalline collective
molecular nonlinear oscillator is discussed. It does not require external
feedbacks of any kind while the oscillator and a time-depending perturbation
both are sustained by incident light. Various dynamical regimes such as
frequency -locked, quasiperiodic, forced and chaotic are observed in agreement
with a theoretical approach developed in the limit of the plane wave
approximation.Comment: 5 pages, 6 figures, submitted to Phys. Rev.
Analytical bond order potential for simulations of BeO 1D and 2D nanostructures and plasma-surface interactions
An analytical interatomic bond order potential for the Be–O system is presented. The potential is fitted and compared to a large database of bulk BeO and point defect properties obtained using density functional theory. Its main applications include simulations of plasma-surface interactions involving oxygen or oxide layers on beryllium, as well as simulations of BeO nanotubes and nanosheets. We apply the potential in a study of oxygen irradiation of Be surfaces, and observe the early stages of an oxide layer forming on the Be surface. Predicted thermal and elastic properties of BeO nanotubes and nanosheets are simulated and compared with published ab initio data.Peer reviewe
A decade of dental education: Faculty of Dentistry
Published on the occasion of the 10th anniversary of the faculty.Incudes bibliographical references.published_or_final_versionConservative dentistry: achievements and perspectives 47Congratulations Wang, Gungwu Wang, Gungwu viiForeword Wei, Stephen H.Y. Wei, Stephen H.Y. ixAcknowledgements Wei, Stephen H.Y. Wei, Stephen H.Y. xiThe Prince Philip Dental Hospital 1Departments and units: a decade of activities and progressStudents' life in the faculty 151Alumni 155Faculty of Dentistry - dental graduates 1985-1992 157The next decade and beyond - some prospects in dentistry 175Brief history of the Faculty of Dentistry 1Administration and governance 4Other services 7Children's dentistry and orthodontics: achievemnets and perspective 13Oral and maxillofacial survey: achievements and perspectives 69Periodontology and public health: achievements and perspectives 95Prosthetic dentistry: achievements and perspectives 113Dental technology unit 125Dental materials science unit: achievements and perspectives 131Oral Biology Unit: achievements and perspectives 139Optimizing adhesion with mineralized dental tissues Gwinnett, A. John Gwinnett, A.John 177Conservative approach to esthetic dentistry Suzuki, M. Mike Suzuki, M. Mike 183The wonderful world of glass ionomer cements Mount, Graham J. Mount, Graham J. 189Biocompatibility of dental materials Smith, Dennis C. Smith, Dennis C. 197Esthetic implant restorations Lewis, Steven Lewis, Steven 203Chemicals in the treatment of periodontal diseases Gjermo, Per Gjermo, Per 21
Quantum partition noise of photo-created electron-hole pairs
We show experimentally that even when no bias voltage is applied to a quantum
conductor, the electronic quantum partition noise can be investigated using GHz
radiofrequency irradiation of a reservoir. Using a Quantum Point Contact
configuration as the ballistic conductor we are able to make an accurate
determination of the partition noise Fano factor resulting from the
photo-assisted shot noise. Applying both voltage bias and rf irradiation we are
able to make a definitive quantitative test of the scattering theory of
photo-assisted shot noise.Comment: 4 pages, 4 figure
Geometrization of metric boundary data for Einstein's equations
The principle part of Einstein equations in the harmonic gauge consists of a
constrained system of 10 curved space wave equations for the components of the
space-time metric. A well-posed initial boundary value problem based upon a new
formulation of constraint-preserving boundary conditions of the Sommerfeld type
has recently been established for such systems. In this paper these boundary
conditions are recast in a geometric form. This serves as a first step toward
their application to other metric formulations of Einstein's equations.Comment: Article to appear in Gen. Rel. Grav. volume in memory of Juergen
Ehler
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