4,747 research outputs found
Efficient binary phase quantizer based on phase sensitive four wave mixing
We experimentally demonstrate an efficient binary phase quantizer operating at low pump powers. Phase-sensitive operation is obtained by polarization mixing the phase-locked signal/idler pair in a degenerate dual-pump vector parametric amplifier
Quadrature decomposition of optical fields using two orthogonal phase sensitive amplifiers
We propose a new technique to optically process coherent signals by simultaneously extracting their two (I and Q) quadrature components into two orthogonal polarizations at the same frequency. Two possible implementations are demonstrated
Signal regeneration techniques for advanced modulation formats
We review recent results on all-optical regeneration of phase encoded signals based on phase sensitive amplification achieved by avoiding phase-to-amplitude conversion in order to facilitate the regeneration of amplitude/phase encoded (QAM) signals
Novel polarization-assisted phase sensitive optical signal processor requiring low nonlinear phase shifts
We demonstrate a new scheme to achieve binary step-like phase response and high phase-sensitive extinction ratio at low powers. Phase-sensitive operation is achieved by polarization filtering phase-locked signal/idler in a degenerate dual-pump vector parametric amplifier
Reliable and Accountable System Design
Few would disagree with the assertion that safe engineering starts from the early stages of system design and should be maintained throughout the lifecycle. Different engineering domains have developed, mostly informal, frameworks with which they hope
to promote this attitude. An interesting question for the KBS community is whether some of our methods for knowledge representation and reasoning can be used to assist in understanding, representing and interpreting such frameworks. This paper concentrates on what is (arguably) the area of greatest concern: relating system requirements to high level design. We highlight what appear to be the major difficulties which face us in this area, using examples from systems which have been built to tackle them.</jats:p
HighâTensile Strength, Composite Bijels through Microfluidic Twisting
Rope making is a millennia old technique to collectively assemble numerous weak filaments into flexible and high tensile strength bundles. However, delicate soft matter fibers lack the robustness to be twisted into bundles by means of mechanical rope making tools. Here, weak microfibers with tensile strengths of a few kilopascals are combined into ropes via microfluidic twisting. This is demonstrated for recently introduced fibers made of bicontinuous interfacially jammed emulsion gels (bijels). Bijels show promising applications in use as membranes, microreactors, energy and healthcare materials, but their low tensile strength make reinforcement strategies imperative. Hydrodynamic twisting allows to produce continuous bijel fiber bundles of controllable architecture. Modelling the fluid flow field reveals the bundle geometry dependence on a subtle force balance composed of rotational and translational shear stresses. Moreover, combining multiple bijel fibers of different compositions enables the introduction of polymeric support fibers to raise the tensile strength to tens of megapascals, while simultaneously preserving the liquid like properties of the bijel fibers for transport applications. Hydrodynamic twisting shows potentials to enable the combination of a wide range of materials resulting in composites with features greater than the sum of their parts
Construção de um instrumento para medida de satisfação no trabalho
O objetivo deste trabalho Ă© a construção de um instrumento para medida da motivação no trabalho. A inspiração teĂłrica para este empreendimento baseou-se, principalmente, nos conceitos de motivação de Maslow (1954), tendo em vista a grande aceitação desta teoria, tanto por parte de psicĂłlogos organizacionais, como de administradores preocupados com o fator humano da empresa. AlĂ©m disso, cabe ainda assinalar a inexistĂȘncia de instrumentos de medida de motivação validados para o uso no Brasil
Wishes and Grumbles
This report summarises the 'wishes and grumbles' session from the Ninth UK Stata Users Group meeting.
Investigation into the role of pump to signal power ratio in FWM-based phase preserving amplitude regeneration
We carry out a detailed experimental characterization of a four-wave mixing based amplitude limiter in highly nonlinear fiber based on the Bessel-like power transfer characteristics and highlight trade-offs for phase preserving capabilities
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