Isogrid structure

Isotropic rib stiffened shell whose ribs intersect to form equilateral triangles has advantages of high twisting rigidity of construction and simplicity of triangular pattern

Efficient Parallelization of Short-Range Molecular Dynamics Simulations on Many-Core Systems

This article introduces a highly parallel algorithm for molecular dynamics simulations with short-range forces on single node multi- and many-core systems. The algorithm is designed to achieve high parallel speedups for strongly inhomogeneous systems like nanodevices or nanostructured materials. In the proposed scheme the calculation of the forces and the generation of neighbor lists is divided into small tasks. The tasks are then executed by a thread pool according to a dependent task schedule. This schedule is constructed in such a way that a particle is never accessed by two threads at the same time.Benchmark simulations on a typical 12 core machine show that the described algorithm achieves excellent parallel efficiencies above 80 % for different kinds of systems and all numbers of cores. For inhomogeneous systems the speedups are strongly superior to those obtained with spatial decomposition. Further benchmarks were performed on an Intel Xeon Phi coprocessor. These simulations demonstrate that the algorithm scales well to large numbers of cores.Comment: 12 pages, 8 figure

Biological Characteristics That Make The Lesser Peachtree Borer (Lepidoptera: Sesiidae) a Pest on Peach Trees

The lesser peachtree borer, Synanthedon pictipes, is a native insect with well distributed hosts near peach orchards, which has high mobility between sylvatic and domestic hosts. It is able to take advantage of the susceptibility of the peach tree to periodic freeze injury and disease cankers. The moth stage is present through most of the growing season and effectively conceals the eggs singly at the most favorable sites for larval success

A unique flight test facility: Description and results

The Dryden Flight Research Facility has developed a unique research facility for conducting aerodynamic and fluid mechanics experiments in flight. A low aspect ratio fin, referred to as the flight test fixture (FTF), is mounted on the underside of the fuselage of an F-104G aircraft. The F-104G/FTF facility is described, and the capabilities are discussed. The capabilities include (1) a large Mach number envelope (0.4 to 2.0), including the region through Mach 1.0; (2) the potential ability to test articles larger than those that can be tested in wind tunnels; (3) the large chord Reynolds number envelope (greater than 40 million); and (4) the ability to define small increments in friction drag between two test surfaces. Data are presented from experiments that demonstrate some of the capabilities of the FTF, including the shuttle thermal protection system airload tests, instrument development, and base drag studies. Proposed skin friction experiments and instrument evaluation studies are also discussed

Fabrication and experimental evaluation of common domes having waffle-like stiffening. part i- program development

Determination of minimum weight shape and stiffening configuration for doubly curved shells subjected to external buckling pressure