Abstract: A queuing system, method and computer program product is provided for transferring electronic information over a data network, such as the Internet. A host or system administrator monitors host resources by preventing one or more host resource limits from being exceeded. Where a resource limit is reached, a queuing protocol is initiated with a client requesting data. The queuing protocol permits the client to enter a queue and wait until host resources may be allocated to service the data request. The queue is maintained by the host, which may provide periodic updates to the client regarding queue length, position and estimated wait time. Clients may advance through the queue in accordance with a first-in-first-out algorithm, or some alternative priority scheme. When a client reaches the head of the queue, host resources are checked. If sufficient resources are available to service the client request, they are allocated to the client at the head of the queue.

Abstract: A multiplicity of one-piece flexure plates are assembled in pairs to provide a support system on which a retroreflector may be mounted for reciprocal motion. Combined with balance bodies, the flexure plates provide a support system having portions that are dynamically and statically balanced with one another, irrespective of orientation, so as to thereby immunize the unit against extraneous forces. The motion transfer assembly is especially adapted for use to support a moving retroreflector in a two-arm interferometer that may further include a beamsplitter assembly constructed from a one-piece, integrally formed body, the body having convergent, optically flat planar surfaces of specular reflectance, and means for adjustably mounting a beamsplitter therein. The spectrometer is of modular construction, and employs an integrated clocking sub-assembly as well as a light-weight voice-coil motor.

Abstract: A folded-path gas cell employs an elliptical concave mirror in confronting relationship to two substantially spherical concave mirrors. At least one of the spherical mirrors, and usually both, are formed with an added cylindrical component to increase orthogonal focii coincidence and thereby to increase the radiation energy throughput characteristic of the cell.