Custom Integrated Circuits

Contains table of contents for Part III, table of contents for Section 1 and reports on eleven research projects.IBM CorporationMIT School of EngineeringNational Science Foundation Grant MIP 94-23221Defense Advanced Research Projects Agency/U.S. Army Intelligence Center Contract DABT63-94-C-0053Mitsubishi CorporationNational Science Foundation Young Investigator Award Fellowship MIP 92-58376Joint Industry Program on Offshore Structure AnalysisAnalog DevicesDefense Advanced Research Projects AgencyCadence Design SystemsMAFET ConsortiumConsortium for Superconducting ElectronicsNational Defense Science and Engineering Graduate FellowshipDigital Equipment CorporationMIT Lincoln LaboratorySemiconductor Research CorporationMultiuniversity Research IntiativeNational Science Foundatio

The decision rule approach to optimization under uncertainty: methodology and applications

Dynamic decision-making under uncertainty has a long and distinguished history in operations research. Due to the curse of dimensionality, solution schemes that naïvely partition or discretize the support of the random problem parameters are limited to small and medium-sized problems, or they require restrictive modeling assumptions (e.g., absence of recourse actions). In the last few decades, several solution techniques have been proposed that aim to alleviate the curse of dimensionality. Amongst these is the decision rule approach, which faithfully models the random process and instead approximates the feasible region of the decision problem. In this paper, we survey the major theoretical findings relating to this approach, and we investigate its potential in two applications areas

Proper orthogonal decomposition of primary breakup and spray in co-axial airblast atomizers

The primary atomisation of a liquid jet by a coaxial stream of high speed gas is analysed by means of Proper Orthogonal Decomposition (POD) for gas to liquid momentum ratios, MR, from 182 to 727 and Weber numbers, We, from 22 to 88. The continuous liquid core is visualised by the optical connectivity technique. The full spray in the near nozzle region is visualised using shadowgraphy. It is found that universal POD modes exist for the continuous liquid core and the near nozzle full spray across all considered flow conditions. The universal POD modes are related to physical structures of the flow. The complexity of the flow, as determined by the energy of the POD modes, is found to be constant for the liquid core across the examined range of flow MR. On the contrary, the complexity of the full spray is inversely proportional to the flow MR. Correlations are established between the spatial and temporal scales of primary atomisation. In addition, a novel method to extrapolate the spatial and temporal scales of the atomisation process beyond the limits of the current measurement resolution is described and demonstrated. Estimates are provided on the number of samples and the sampling rate that are required to fully resolve the flow to specific temporal and spatial scales

Proper orthogonal decomposition of primary breakup and spray in co-axial airblast atomizers

The primary atomization of a liquid jet by a coaxial stream of high speed gas is analyzed by means of Proper Orthogonal Decomposition (POD) for gas to liquid momentum ratios (MR) from 182 to 727 and Weber numbers, We, from 22 to 88. The continuous liquid core is visualized by the optical connectivity technique. The full spray in the near nozzle region is visualized using shadowgraphy. It is found that universal POD modes exist for the continuous liquid core and the near nozzle full spray across all considered flow conditions. The universal POD modes are related to physical structures of the flow. The complexity of the flow, as determined by the energy of the POD modes, is found to be constant for the liquid core across the examined range of flow MR. On the contrary, the complexity of the full spray is inversely proportional to the flow MR. Correlations are established between the spatial and temporal scales of primary atomization. In addition, a novel method to extrapolate the spatial and temporal scales of the atomization process beyond the limits of the current measurement resolution is described and demonstrated. Estimates are provided on the number of samples and the sampling rate that are required to fully resolve the flow to specific temporal and spatial scales. © 2019 Author(s)