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Investigation of Microbiological Regrowth after Ultraviolet DisinfectionMa, Daniel T. January 2020 (has links)
No description available.
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262 |
Studies of Atmospheric Pressure Visible-Wavelength MALDI-MSSun, Zhen 20 September 2012 (has links)
No description available.
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263 |
Wavelength Multiplexing of MEMS Pressure and Temperature Sensors Using Fiber Bragg Gratings and Arrayed Waveguide GratingsLi, Weizhuo January 2005 (has links)
No description available.
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264 |
On Optimal Survivability Design in WDM Optical Networks under Scheduled Traffic ModelsLi, Tianjian 18 April 2007 (has links)
No description available.
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265 |
The Development and Applications of Soft Visible-Wavelength LDI, UV LDI, and DESI Sources for the Analyses of Biomolecules by Mass SpectrometryWest, Raymond Edward, III January 2016 (has links)
No description available.
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266 |
True-time all optical performance monitoring by means of optical correlationAbou-Galala, Feras Moustafa 06 June 2007 (has links)
No description available.
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267 |
Design and Fabrication of Highly Reflective DBRs for use with Long Wavelength VCSELsShahideh, Mehdi 07 1900 (has links)
This project successfully designed, fabricated and characterized two highly reflective distributed Bragg reflectors for use with long wavelength vertical cavity surface emitting lasers. The first reflector consisted of 20 pairs of alternating lnP/Ino.64Gao.36Aso.777Po.223 layers grown on an InP substrate with a theoretically predicted normal incident reflectivity of 96.6% at a center wavelength of 1550nm. The second DBR had 20 pairs of alternating GaAs/Ino.484Gao.5i6P layers grown on a GaAs substrate with a theoretically predicted reflectivity of 94.9% at a center wavelength of 1550nm for normal incident light. Experimental results obtained using a specially designed reflectivity measurement setup confirmed reflectivity models and predictions at both normal and variable incident light angles. However, these measurements revealed a discrepancy between theoretical and experimental layer thickness values for both DBR structures. Applying perturbations to the theoretical models, the actual layer thicknesses of the DBRs were determined. X-ray analysis was employed to examine the periodicity of the super-lattices along with the accuracy of lattice matching to the substrate. Transmission electron microscopy revealed that no detectable drift in layer thickness was apparent during growth of the DBR structures. Photoluminescence was used to investigate any compositional variations of the quaternary layers in the first DBR stack. / Thesis / Master of Applied Science (MASc)
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Injection-Locked Fabry-Perot Laser Diode In Wavelength Division Multiplexing Passive Optical NetworkYan, Yudan 07 1900 (has links)
The bandwidth demanding in the access network has been increasing rapidly over the past several years. The predominant broadband access network solutions deployed today are digital subscriber line (DSL) and community antenna television (CATV) (cable TV) based networks. However, the passive optical network (PON) which is a point to multipoint access network based on optical fibers provides much higher bandwidth compared to current access networks based on copper lines. Incorporating wavelength division multiplexing (WDM) in a PON allows a much higher bandwidth compared to the standard PON which operates in the single wavelength mode where the one wavelength is used for upstream transmission and another different wavelength is used for downstream transmission. Moreover, WDM-PON offers the advantages in terms of capacity, low latency and service transparency. In the past five years WDM-PON technology has been developed to a mature for commercial consideration. In this thesis, we start from some fundamentals about WDM-PON and the technology challenge for WDM-PON which is to avoid the need for expensive wavelength selective optical components in the end-user optical network unit (ONU). Then we investigate Injection Locked Fabry-Perot Laser Diode with narrow band amplified spontaneous emission (ASE) noise as an approach to be a wavelength independent ONU. We study its theoretical model and compare the experimental results with the simulation results based on the theoretical model. / Thesis / Candidate in Philosophy
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Numerical simulations of vortices near free and solid surfacesLuton, J. Alan 05 October 2007 (has links)
The interaction of vortices passing near free and solid surfaces has been examined using direct numerical simulation (DNS). A computer code was developed which solves the unsteady, three-dimensional Navier-Stokes equations for incompressible flow. A critical element of the numerical scheme is the efficient solution of Poisson's equation. A state of the art solver based on multigrid techniques was developed which gives excellent convergence rates. The result is a tool capable of modeling complex three-dimensional flows in a variety of configurations.
Three different flow fields have been examined in order to determine some of the complex interactions involved between a vortex and a surface. The first concerns the two-dimensional interaction between a boundary layer and a convecting vortex. The size and height above the wall of the vortex are the same order of magnitude as the boundary layer thickness. A strong primary vortex creates a secondary vortex which causes the rebound of the primary, a response observed in many previous studies. However, weaker vortices as well do not follow the inviscid trajectory despite the absence of a secondary vortex. Rather than creating vorticity at the wall, a weaker vortex mainly redistributes the vorticity of the boundary layer. The redistributed vorticity alters the path of the vortex in ways not seen for vortex/wall interactions. / Ph. D.
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Wavelength compensation in fused fiber couplersWang, Zhi G. 06 June 2008 (has links)
The performance of fused fiber couplers is wavelength dependent. Wavelength spectral compensation is a technique to decrease the effect of the wavelength dependence, which is an essential task for many applications in fiber optic communication systems. Fiber devices such as wavelength-flattened couplers (WFCs) can be fabricated using wavelength spectral compensation methods. In this dissertation, wavelength spectral compensation techniques in fused biconical taper (FBT) couplers including both multimode and single-mode fiber couplers are studied in detail. In multimode fiber coupler operation, a novel theoretical model based on frustrated total internal reflection (FTIR) has been developed to effectively describe the power coupling and loss mechanism. Experimental results support the theoretical predictions. In single-mode fiber couplers, the conventional technique of fabricating WFCs is discussed. An alternative analytical model has been developed based upon coupled mode theory, which provides a relatively simple and mathematically sound explanation to the wavelength spectral compensation. Aiming to simplify WFC fabrication, a new way of constructing WFCs is proposed and demonstrated by connecting regular single-mode fiber couplers, some of which serve as wavelength spectral compensators. WFCs of various structures including 2x2, 1x3, 1x2ᴺ, and 4x4 have been developed, and the experimental data agree with theoretical predictions of performance. Potential applications and future research directions in wavelength spectral compensation are also presented. / Ph. D.
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