We report on the observation of “hole” whispering gallery lasers from semiconductor microcavities with three dimensional optical confinement, with thresholds potentially reducible to micro- to nanoampere regimes according to a quadratic size-dependent reduction, consistent with a photonic quantum corral effect of naturally formed recombinant quantum rings. If the device size grows over a critical diameter, the quantum ring whispering gallery then begins to disappear. However, cooperative small hole laser arrays, exhibiting photonic crystal structure properties, avoid the criticality and open a possibility of constructing practical high-density electropumped emitter arrays.

In this study, an advanced method was proposed for the empirical formation of current profiles which can be directly used for the numerical analysis of offshore structures. A probabilistic approach was adopted to generate a reliable empirical model which can be expressed as a function of current velocity and water depth from the obtained best fit probability density function (PDF) with sub-parameters. It is recognised that the statistical scatter of current velocity at each normalised water depth is wide and requires a reliable method (or technique) with a refined manner to generate a simplified current profile model. From the probabilistic approach, the best-fit PDF of the current velocity distribution, including all ranges of normalised water depth is decided. In addition, sub-parameters of PDF (i.e., shape, scale, location parameters) can also be formulated as a function of normalised water depth through curve-fitting.For better understanding, three (3) main steps which are 1) individual, 2) overall, and 3) optimised outcomes have been highlighted in order to propose the empirical formulation of current profiles. For the publication in Marine StructuresApplicability of the proposed method was verified by collecting 54 current profiles obtained from existing offshore fields, thus making it possible to generate a more accurate current profile model.

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Microstmcture and mechanical properties of the strip-cast Ni-base superalloy(HasteHoy-X) alloy have been compared with those of a conventionally ingot-cast alloy. As-cast strip shows a fine columnar dendritic structure as a result of a relatively high cooling rate of 102-104K/sec during the process. The alloying elements, such as Cr and Fe, are homogeneously distributed in the u matrix of the as-cast strip. Whereas, Mo is segregated at the center part of the as-cast strip. Mo distribution, however, becomes homogenetms after cold rolling and subsequent heat treatment at 1175~ Two types of carbide, a Mo-rich MrC type and a Cr-rich M z~C-~ type, are present in the u matrix of the as-cast and rolled strips. Rolling and subsequent heat treatment of the strip-cast alloy result,; in a fine grain slrm:ture compared to the ingot-cast alloy. The u matrix grains in stripcast and ingot.cast alloy are approximately 14 Ittm and 34 pan in diameter respectively. Superior tensile properties in the strip-cast .,alloy is due to the Vane rnictostmctural evolution during the process.