The main aim of this thesis has been to contribute to the ongoing work with development of new diode-laser-based spectroscopic techniques and metho­do­lo­gies for sensitive detection of molecules in gas phase. The techniques under scrutiny are tunable diode laser absorption spectrometry (TDLAS) and Faraday modulation spectrometry (FAMOS). Conventional distributed-feedback (DFB) tele­communication diode lasers working in the near-infrared (NIR) region have been used for detection of carbon monoxide (CO) and temperature in hot humid media whereas a unique frequency-quadrupled external-cavity diode laser producing mW powers of continuous-wave (cw) light in the ultra violet (UV) region have been used for detection of nitric oxide (NO). A methodology for assessment of CO in hot humid media by DFB-TDLAS has been developed. By addressing a particular transition in its 2nd overtone band, and by use of a dual-fitting methodology with a single reference water spectrum for background correction, % concentrations of CO can be detected in media with tens of percent of H2O (≤40%) at T≤1000 °C with an accuracy of a few %. Moreover, using an ordinary DFB laser working in the C-band, a technique for assessment of the temperature in hot humid gases (T≤1000 °C) to within a fraction of a percent has been developed. The technique addresses two groups of lines in H2O that have a favorable temperature dependence and are easily accessed in a single scan, which makes it sturdy and useful for industrial applications. A technique for detection of NO on its strong electronic transitions by direct absorption spectrometry (DAS) using cw UV diode laser light has been deve­loped. Since the electronic transitions are ca. two or several orders of magnitude stronger than of those at various rotational-vibra­tional bands, the system is capable of detecting NO down to low ppb∙m concentrations solely using DAS. Also the FAMOS technique has been further developed. A new theoretical description expressed in terms of both the integrated line strength of the transition and 1st Fourier coefficients of a magnetic-field-modulated dispersive lineshape functions is presented. The description has been applied to both ro-vib Q-transitions and electronic transitions in NO. Simulations under different pressures and magnetic field conditions have been made that provide the optimum conditions for both cases. A first demonstration and characteri­zation of FAMOS of NO addressing its electronic transitions in the UV-region has been made, resulting in a detection limit of 10 ppb∙m. The characterization indicates that the technique can be significantly improved if optimum conditions can be obtained, which demonstrates the high potential of the UV-FAMOS technique.

Orientador: Mauricio Ferreira Magalhães / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-08T01:20:28Z (GMT). No. of bitstreams: 1 Zuliani_LuizGustavo_M.pdf: 512812 bytes, checksum: cab94937633f70467669b12635e8ccb1 (MD5) Previous issue date: 2006 / Resumo: Redes totalmente ópticas (fotônicas) controladas por GMPLS (Generalized MultiProtocol Label Switching) são a promessa para lidar com o crescente volume de tráfego IP. Os protocolos de sinalização e roteamento GMPLS, principalmente OSPF (Open Shortest Path First) e RSVP (Resource ReSerVation Protocol), trabalham de tal modo que o cálculo da rota para circuitos ópticos não considera a disponibilidade de comprimentos de onda (labels). Esta solução não é ótima em termos do uso de recursos de rede e da probabilidade de bloqueio de novos circuitos. Para aprimorar este quadro, algoritmos RWA (Routing and Wavelength Assignment) mais eficientes poderiam ser usados para calcular a rota e o comprimento de onda simultaneamente. Estes algoritmos RWA necessitam conhecer a topologia óptica de um modo ainda não descrito pelas atuais especificações do protocolo OSPF. Esta dissertação propõe extensões de Engenharia de Tráfego para o protocolo OSPF para permitir que o plano de controle GMPLS se beneficie do uso de algoritmos RWA mais eficientes. Um protótipo foi desenvolvido e instalado em uma rede óptica emulada para verificar a praticabilidade da solução proposta baseado na sobrecarga de tráfego gerado no plano de controle / Abstract: GMPLS-controlled all-optical networks are the promise to handle the increasing volume of IP traffic. The GMPLS routing and signaling protocols, mainly OSPF and RSVP, work in such a way that the route calculation for optical circuits does not take into account the wavelength (label) availability. This is not optimal in terms of network resources usage and blocking probability of new circuits. To deal with this scenario, more efficient RWA algorithms could be used to calculate the route and the wavelength assignment at one time. These RWA engines need to know the optical topology in a way that is not described by current OSPF standards. This dissertation proposes Traffic Engineering extensions to the OSPF protocol to enable the GMPLS control plane to take advantage of the most effective RWA classes. A prototype was developed and deployed in an optical-emulated copper-based network to verify its feasibility based on the bandwidth overhead generated in the control plane / Mestrado / Engenharia de Computação / Mestre em Engenharia Elétrica