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Turkish censorship, cultural translation, and the trial of William S. Burroughs's the soft machine
No full textErratum: Large spectral tuning of liquid microdroplets by optical scattering force (Applied Physics Letters (2007) 91 (231102))
No full textErratum: Innate lymphoid cells in asthma phenotypes (Clinical and Translational Allergy (2015) 5 (23)
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A numerical and experimental study of optimal velocity feedback control for vibration suppression of a plate-like structure
No full textThis study presents a numerical and an experimental study on an active vibration control system. The system includes a fully-clamped plate and two surface bonded piezoelectric actuators and a collocated velocity sensor at one of the actuator locations. One of the piezoelectric actuators is used for disturbance actuation and the other one is used for control actuation. A model based optimal velocity feedback controller is used as control algorithm. The disturbance and actuator models are obtained through experimental characterization of the plate under the effect of the disturbance source. A representative SIMULINK model is built in parallel to the development of the experimental setup in order to investigate performance of the controller for various control parameters. After the model based optimal controller is designed, performance of the optimal velocity feedback controller is validated with the experimental study by comparing the vibration suppression values at multiple modes of the structure. Results show that the developed control methodology effectively suppresses the vibration amplitudes at multiple modes of the structure and also vibration attenuation levels can be predicted accurately with the simulations for various controller design parameters. It is also demonstrated that using an optimal controller enhances the performance of the system as opposed to just using velocity feedback algorithm for the active vibration control of the smart plate
Luminescence of black silicon
No full textRoom temperature visible and near-infrared photoluminescence from black silicon has been observed. The black silicon is manufactured by shining femtosecond laser pulses on silicon wafers in air, which were later annealed in vacuum. The photoluminescence is quenched above 120 K due to thermalization and competing nonradiative recombination of the carriers. The photoluminescence intensity at 10K depends sublinearly on the excitation laser intensity confirming band tail recombination at the defect sites
Dielectric resonators based on amorphous silicon
No full textIn this paper, we report on the design, modeling, fabrication, and characterization of dielectric microresonators based on hydrogenated amorphous silicon nitride and hydrogenated amorphous silicon oxide. The microresonators were modelled using the transfer matrix method (TMM). Quarter wavelength thick stacks of hydrogenated amorphous silicon nitride and hydrogenated amorphous silicon oxide were consecutively deposited using low temperature plasma enhanced chemical vapor deposition (PECVD). For the characterization of the dielectric microresonators the intrinsic photoluminescence of the amorphous silicon nitride is used. The photoluminescence is enhanced by at least an order of magnitude at the resonance wavelength of 710 nm. The minimum resonance linewidth is 6 nm, corresponding to a quality factor of 118. The maximum rejection bandwidth of the distributed Bragg reflector (DBR) is 150 nm. The enhancement and inhibition of the photoluminescence is understood by the modified photon density of states of the dielectric microresonator. The linewidth of the photoluminescence is also narrowed with respect to the linewidth of the bulk amorphous silicon nitride, again due to the presence of the electromagnetic modes of the microresonator
Dualisation of the Salam-Sugin D-8 supergravity
No full textThe first-order formulation of the Salam-Sezgin D = 8 supergravity coupled to N vector multiplets is discussed. The non-linear realization of the bosonic sector of the D = 8 matter coupled Salam-Sezgin supergravity is introduced by the dualisation of the fields and by constructing the Lie superalgebra of the symmetry group of the doubled field strength. (C) 2004 Published by Elsevier B.V
Brand concepts as representations of human values: do cultural congruity and compatibility between values matter?
No full textGlobal brands are faced with the challenge of conveying concepts that not only are consistent across borders but also resonate with consumers of different cultures. Building on prior research indicating that abstract brand concepts induce more favorable consumer responses than functional attributes, the authors introduce a generalizable and robust structure of abstract brand concepts as representations of human values. Using three empirical studies conducted with respondents from eight countries, they demonstrate that this proposed structure is particularly useful for predicting (1) brand meanings that are compatible (vs. incompatible) with each other and, consequently, more (less) favorably accepted by consumers when added to an already established brand concept; (2) brand concepts that are more likely to resonate with consumers with differing cultural orientations; and (3) consumers' responses to attempts to imbue an established brand concept with new, (in)compatible abstract meanings as a function of their own cultural orientations
Pseudo-Hermiticity versus PT-symmetry. II. A complete characterization of non-Hermitian Hamiltonians with a real spectrum
No full textWe give a necessary and sufficient condition for the reality of the spectrum of a non-Hermitian Hamiltonian admitting a complete set of biorthonormal eigenvectors