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Future aerospace vehicles like 'Hybrid wing/body', 'Truss-braced Wing' and 'DoubleBubble' would be having pressurized non-circular fuselage structures and complex wing geometry. Traditional aircraft designs have led to the confidence and experience of designing such structures using the knowledge-base built over the years and the resulting thumb-rules. However, there is a lack of experience of load-calculations and design of complex, multifunctional, aircraft structural concepts for future aerospace vehicles. Designing such structures will require a physics-based optimization framework, so a new optimization framework, EBF3PanelOpt is being developed. Commercial software, MD-PATRAN(Geometry modeling and mesh generation), MD-NASTRAN (Finite Element Analysis), are integrated in EBF3PanelOpt framework using Python programming environment to design stiffened panels with curvilinear stiffeners. Currently, EBF3PanelOpt is supported with curvilinear blade stiffeners without loads through the stiffeners to optimize the panels for minimum mass subjected to buckling, von Mises stress, and crippling or local failure of the stiffener constraints. EBF3PanelOpt is enhanced to have curvilinear T stiffeners with or without axial loads in addition to loads through plate. The panel/stiffener geometry is defined in a parametric fashion based on design variables that include variables for orientation and shape of the stiffeners, the thicknesses and heights of the webs and flanges of the stiffeners, and the plate pockets thicknesses. This framework is supported with coarse-grained parallelism using Python to analyze multiple designs on the cluster. Using this framework, a vertical stabilizer skin panel of transport aircraft panel having two extreme load-cases, is optimized using with or without stiffener loads. When the equivalent uniform loads are applied through the plate only, plate buckling becomes critical during the optimization as compared to combined buckling of plate and stiffeners when loads applied through the plate and stiffeners. Straight T stiffened panel is optimal than curvilinearly T stiffened panel when the loads are applied through both the plate and stiffeners.

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In this paper we describe a distributed-memory parallel implementation of the Open Network Emulator (ONE), a network simulator that combines the controllability of simulation with the direct code execution advantages of emulation and experimental testbeds. ONE uses a scaled real-time model called Relativistic Time (RT). We describe a RT-based reactive global warp detection algorithm to exploit lookahead. The Distributed ONE system provides a platform for network simulation that combines model fidelity (existing network applications can be compiled and instantiated within ONE without modification), temporal fidelity, and good scalability. We present strong and weak scaling performance results for the Distributed ONE system on up to sixteen nodes of a distributed-memory parallel cluster, on simulations involving up to 16,000 virtual hosts.