Context Switching in a Run-Time Reconfigurable System

A distinguishing feature of reconfigurable computing over rapid prototyping is its ability to configure the computational fabric on-line while an application is running. Conventional reconfigurable computing platforms utilize commodity FPGAs, which typically have relatively long configuration times. Shrinking the configuration time down to the nanosecond region opens possibilities for rapid context switching and virtualizing the computational resources. An experimental context-switching FPGA, called the CSRC, has been created by BAE Systems, and gives researchers the opportunity to explore context-switching applications. This paper presents results obtained from constructing both control-driven and data-driven context switching applications on the CSRC device, along with unique properties of the run-time and compile-time environment.     

Investigations on physical,mechanical, morphological and water absorption properties of ramie/hemp/kevlar reinforced vinyl ester hybrid composites

Structural uses in the vehicle, aerospace, and sporting goods industries are being supplanted by hybrid composites that utilized natural fibers as reinforcements. The main focus of this work is to fabricate and characterize the ramie, hemp, and kevlar fabric reinforced hybrid vinyl ester composites. The composite laminates were fabricated via economically feasible and flexible hand lay-up technique. Overall six composites were prepared by varying the stacking sequence, including both hybrid and non-hybrid composites. The prepared composites were subjected to physical analysis (density, void fraction), mechanical tests (tensile, flexural, interlaminar shear, and impact test), morphological analysis (scanning electron microscopy), and water absorption test. The hybrid composites exhibited lesser void percentage than the non-hybrid composites. The mechanical properties were maximum for kevlar fabric skinned with core natural fabric reinforced composites (L-5, L-6) due to hybridization of highly strengthened kevlar fabrics. Moreover, the number fabric layers reinforced to achieve the standard thickness also affected the mechanical properties. All composite morphologies exhibited the same failure characteristics, including transverse interlaminar shear cracking, microbuckling, and fiber rip. The texture of the Kevlar yarns is uniform, but the texture of the natural fabric yarns is relatively less uniform. In comparison to the salt water medium, the percentage of water absorbed by composites in normal and distilled water was greater. This is due to the presence and accumulation of salt particles on the surface of the materials, which inhibits the action of water molecules, resulting in a drop in the proportion.