The works of Thomas Hearne, M. A.

With reprints of original t.-p. for chronicles of Robert of Gloucester and Peter Langtoft.

InP-based active and passive components for communication systems at 2 μm

Progress on advanced active and passive photonic components that are required for high-speed optical communications over hollow-core photonic bandgap fiber at wavelengths around 2 μm is described in this paper. Single-frequency lasers capable of operating at 10 Gb/s and covering a wide spectral range are realized. A comparison is made between waveguide and surface normal photodiodes with the latter showing good sensitivity up to 15 Gb/s. Passive waveguides, 90° optical hybrids, and arrayed waveguide grating with 100-GHz channel spacing are demonstrated on a large spot-size waveguide platform. Finally, a strong electro-optic effect using the quantum confined Stark effect in strain-balanced multiple quantum wells is demonstrated and used in a Mach-Zehnder modulator capable of operating at 10 Gb/s.

A survey of the northern neck of Virginia, being the lands belonging to the Rt. Honourable Thomas Lord Fairfax Baron Cameron, bounded by & within the Bay of Chesapoyocke and between the rivers Rappahannock and Potowmack: With the courses of the rivers Rappahannock and Potowmack, in Virginia, as surveyed according to order in the years 1736 & 1737.

Scale ca. 1:875,000.

Improving the Flexibility of Active Grids through Web Services

Active Grids are a form of grid infrastructure where the grid network is active and programmable. These grids directly support applications with value added services such as data migration, compression, adaptation and monitoring. Services such as these are particularly important for eResearch applications which by their very nature are performance critical and data intensive. We propose an architecture for improving the flexibility of Active Grids through web services. These enable Active Grid services to be easily and flexibly configured, monitored and deployed from practically any platform or application. The architecture is called WeSPNI ('Web Services based on Programmable Networks Infrastructure'). We present the architecture together with some early experimental results on using web services to monitor data movement in an active grid.