The impact of global routing on the performance of NoCs in FPGAs

With the over-provisioned routing resource on FPGA, the topology choice for NoC implementation on FPGA is more flexible than on ASIC. However, it is well understood that the global wire routing impacts the performance of NoC on FPGA because the topology is routed by using fixed routing fabric. An important question that arises is: will the benefit of diameter reduction by using a highly connective topology outweigh the impact of global routing? To answer this question, we investigate FPGA based packet switched NoC implementations with different sizes and topologies, and quantitatively measure the impact of global routing to each of these networks. The result shows that with sufficient routing resources on modern FPGA, the global routing is not on the critical path of the system, and thus is not a dominating factor for the performance of practical multi-hop NoC system. © 2011 IEEE.

Experimental investigation of drive-by bridge inspection

This study presents a vibration-based health monitoring of short span bridges by
an inspection vehicle. How to screen health condition of short span bridges in terms of the
drive-by bridge inspection is described. Feasibility of the drive-by bridge inspection is
investigated through a scaled laboratory moving vehicle experiment. The feasibility of using an
instrumented vehicle to detect the natural frequency and changes in structural damping of a
model bridge is observed. Observations also demonstrate possibility of diagnosis of bridges by
comparing patterns of identified dynamic parameters of bridges through a periodical
monitoring. It is confirmed that the method for damage identification under a moving vehicle
identifies the damage location and severity well.

Monitoring of a novel FlexiArchTM bridge system to investigate soil-structure interaction

Masonry arch bridges are one of the oldest forms of bridge construction and have been around for thousands of years. Brick and stone arch bridges have proven to be highly durable as most of them have remained serviceable after hundreds of years. In contrast, many bridges built of modern materials have required extensive repair and strengthening after being in service for a relatively short part of their design life. This paper describes the structural monitoring of a novel flexible concrete arch known as: FlexiArchTM. This is a bridge system that can be transported as a flat-pack system to form an arch in-situ by the use of a flexible polymeric membrane. The system has been developed under a Knowledge Transfer Partnership between Queen’s University Belfast (QUB) and Macrete Ltd. Tievenameena Bridge in Northern Ireland was a replacement bridge for the Northern Ireland Roads Service and was monitored under different axle loadings using a range of sensors including discrete fiber optic Bragg gratings to measure the change in strain in the arch ring under live loading. This paper discusses the results of a laboratory model study carried out at QUB. A scaled arch system was loaded with a simulated moving axle. Various techniques were used to monitor the arch under the moving axle load with particular emphasis on the interaction of the arch ring and engineered backfill.