In this paper, a brief summary of different methods of fabrication of optical preform and fiber is reviewed. Several methods of incorporation of erbium ions into optical preforms are studied. Characterization of the fabricated erbium doped fibers including measurements of refractive index profile, absorption, fluorescence and gain spectra and metastable lifetime are described. It is also expres...

An alternative fabrication technique is proposed for ceramic matrix / ceramic fibre composites involving filling a fibre fabric preform with a SiSi N slurry and subsequently reaction bonding. For the first processing step in this process, chemical vapour infiltration (CVI) was evaluated as a means of both binding together and protecting the fibres. Sic (Nicalon) fibre p re fom consisting of thr...

We introduce two refinements of the neutral stability criterion, namely the ascending and the eroding neutrally stable strategies (NSS). These criteria take into account how well the NSS preform against all pure strategies in symmetric two-player games. We also present a dynamic model which supports the refinements.

We obtain the maximum likelihood estimator of the central subspace under conditional normality of the predictors given the response. Analytically and in simulations we found that our new estimator can preform much better than sliced inverse regression, sliced average variance estimation and directional regression, and that it seems quite robust to deviations from normality.

In this work, fibre Bragg gratings (FBGs) were inscribed in two different undoped poly- (methyl methacrylate) (PMMA) polymer optical fibres (POFs) using different types of UV lasers and their inscription times, temperature and strain sensitivities are investigated. The POF Bragg gratings (POFBGs) were inscribed using two UV lasers: a continuous UV HeCd @325 nm laser and a pulsed UV KrF @248 nm ...

Finite-Element (FE) simulations are a valuable tool to support the analysis and optimization of production processes. In order to achieve realistic simulation results, a consistent simulation set-up followed by an evaluation through experiments is crucial. Stretch Blow Molding (SBM) is a commonly applied forming method to produce thin walled bottles. Polyethylene terephthalate (PET) preforms ar...

Abstract SiC fiber-reinforced matrix composites (SiC f /SiC) with 2D woven fabric as preform were tested under compression in-situ X-ray computed tomography. The microstructure and damage evolution of the material continuous loading levels accurately revealed by image reconstruction CT data. There inhomogeneous pores in /SiC composite because un-uniform fiber distribution preform. result also s...

Reaction bonded silicon carbide (RBSiC) has a wide variety of industrial applications and a manufacturing process based on Selective Laser Sintering (SLS) has been demonstrated in previous research at the University of Texas. That study was directed toward semiconductor manufacturing applications and was based on prior indirect SLS methods. Several key research questions were addressed for thre...

The main advantage of multidirectionally reinforced composites is the freedom to orient selected fiber types and hence derives the benefits of varying fibre volume fractions and there by accommodate the design loads of the final structure of composites. This technology provides the means to produce tailored composites with desired properties. Due to the high level of fibre integrity with throug...

To test a model recently proposed to account for the observation of efficient second-harmonic generation in glass fibers, we have applied a strong dc electric field to the glass preform from which the fibers were drawn. We find that at most a temporary x(2) is induced, with a lifetime of a few minutes.