Search results for "Online"
showing 10 items of 4526 documents
Exploring User Behavior in Destination Websites: An Application of Web Mining Techniques
2021
The development of the Internet has so strongly affected the way a tourist destination can be promoted that portals now play an important role in defining the marketing strategies of tourist destinations. Hence, investigating website surfing behavior has become crucial to understanding the needs of potential tourists. Using Web Mining techniques, our study explores the information-seeking behavior of those who log on to a website promoting the island of Sicily, a well known tourist destination in the South of Italy. The study explores whether a tourist’s country of origin affects their information needs and surfing behavior. Actually, our results do show differences in behavior between user…
Third-harmonic generation in optical microfibers: From silica experiments to highly nonlinear glass prospects
2012
International audience; Using optical microfibers, phase matching between different propagation modes allows for third-harmonic generation (THG). After detailing the relevant phase matching conditions and overlap integrals, we provide a comparison between THG effective efficiencies in silica and tellurite glasses. We also explain the relatively easy, wideband, conversion that we observe experimentally in silica glass microfibers, from 155 mu m to the green, by the geometry of the tapering region.
Helical Shift Mechanics of Rubber V-Belt Variators
2011
A very common configuration of V-belt variators for motorcycles considers the correction of the belt tensioning depending on the resistant torque by means of suitable helical-shaped tracks allowing the driven half-pulleys to close/open. The theoretical model for belt-pulley coupling is rather complex for this configuration, where one half-pulley may run in advance and the other one behind with respect to the belt, and requires the repeated numerical solution of a strongly nonlinear differential system by a sort of shooting technique, until all the operating conditions are fulfilled (angular contact extent, torque, and axial force). After solving the full equations, the present study develop…
Effectiveness of a web-based acceptance and commitment therapy program for adolescent career preparation : A randomized controlled trial
2021
Acceptance and commitment therapy (ACT) programs have rarely been used as tools for promoting adolescents' career preparation. This randomized controlled trial examined the possibility to promote the career preparation of Finnish ninth-grade adolescents (n = 249, 49% females) with a web-based five-week ACT-based online intervention program. Participants were randomly assigned to three conditions, of which two groups received an iACT including support via SMS (iACTface: iACT+two face-to-face sessions; only iACT: iACT with no face-to-face sessions) and the third (control) group received no treatment. The results showed that career-related insecurity decreased as a result of the intervention i…
Tiešsaistes uzdevumi angļu valodas vārdu krājuma apguvei sākumskolā
2015
Diplomdarba mērķis ir izpētīt kā tiešsaistes uzdevumi ietekmē angļu valodas vārdu krājuma apguvi sākumskolā. Diplomdarba autore uzskata, ka vārdu krājuma apguve ir viens no nozīmīgākajiem valodas aspektiem, kam ir liela nozīme sākumskolas skolēnu mācīšanā. Diplomdarba mērķa sasniegšanai darba autore izvēlējas atsevišķa gadījuma pētījuma metodi. Metodes, kas tika izmantotas datu vākšanā, ir anketēšana, priekšpārbaude un pēcpārbaude. Lai pārbaudītu kā tiešsaistes uzdevumi ietekmē skolēnu vārdu krājuma bagātināšanos, kopumā tika novadītas četras mācību stundas. Pētījuma rezultātā ir konstatēts, ka vairākums skolēnu ar tiešsaistes uzdevumiem uzlaboja savu vārdu krājumu. Darba autore secināja, k…
Airy-function approach to binary black hole merger waveforms: The fold-caustic diffraction model
2022
From numerical simulations of the Einstein equations, and also from gravitational wave observations, the gravitational wave signal from a binary black hole merger is seen to be simple and to possess certain universal features. The simplicity is somewhat surprising given that non-linearities of general relativity are thought to play an important role at the merger. The universal features include an increasing amplitude as we approach the merger, where transition from an oscillatory to a damped regime occurs in a pattern apparently oblivious to the initial conditions. We propose an Airy-function pattern to model the binary black hole (BBH) merger waveform, focusing on accounting for its simpl…
Selective protein removal and desalting using microchip CE.
2006
Abstract This paper describes the on-line sample pretreatment and analysis of proteins and peptides with a poly(methylmethacrylate) (PMMA) microfluidic device (IonChip™). This chip consists of two hyphenated electrophoresis channels with integrated conductivity detectors. The first channel can be used for sample preconcentration and sample clean-up, while in the second channel the selected compounds are separated. Isotachophoresis (ITP) combined with zone electrophoresis (CZE) was used to preconcentrate a myoglobin sample by a factor of about 65 before injection into the second dimension and to desalt a mixture of six proteins with 100 mM NaCl. However, ITP–CZE could not be used for the rem…
Nonlinear optical susceptibilities of polysilanes: exciton effect
1992
Abstract Third-order nonlinear optical susceptibilities of σ-conjugated one-dimensional polymers have been calculated in a tight-binding model by taking account of the formation of excitons due to long-range Coulomb interactions. The spectrum of third-harmonic generation (THG) exhibits peaks due to excitons as well as unbound electron—hole states, in contrast to the linear absorption spectrum which is dominated by the lowest exciton state. The results are in excellent agreement with recent experiments in polysilanes not only for THG but also for linear absorption, two-photon absorption, and electroabsorption in a mutually consistent way.
Toward device applicable second order NLO polymer materials: definition of the chromophore figure of merit
2007
Maximal achieved second order non linear optical (NLO) efficiency of the PMMA based host – guest systems containing eight dimethylaminobenzylidene -1, 3 - indandione (DMABI) related chromophores have been analysed. Two contradicting sets of NLO chromophore figure of merit (FOM) equations were tested. One of them predicts that NLO efficiency of the poled polymer host -guest film is proportional to ground state dipole d33 ~ 1/μg, another to d33 ~ 1/μg. The best correlations for the maximal achieved nonlinearity were obtained with second set of FOM, especially if high ground state dipole (μg > 7D) chromofores are included in analysis.
Dynamics of Glassy Polymer Melts in Confined Geometry: A Monte Carlo Simulation
1996
Dynamic properties of a dense polymer melt confined between two hard walls are investigated over a wide range of temperatures by dynamic Monte Carlo simulation. The temperature interval ranges from the ordinary liquid to the strongly supercooled melt. The influence of temperature, density and confinement on the polymer dynamics is studied by various mean-square displacements, structural relaxation functions and quantities derived from them (relaxation times, apparent diffusion coefficients, monomer relaxation rates), yielding the following results: The motion of the monomers and polymers close to the walls is enhanced in parallel, but reduced in perpendicular direction. This dynamic anisotr…