Abstract: The current invention is related to a system and a method for session overload protocol (SIP) server overload detection and control. The current invention proceeds by receiving SIP messages at the SIP server from a communications network; processing the received SIP messages; detecting an overload based on a trigger condition as a result of receiving and processing SIP messages; and transitioning the SIP server to an overload state and applying appropriate control actions to mitigate the detected overload.

Abstract: The current invention is related to a system and a method for session overload protocol (SIP) server overload detection and control. The current invention proceeds by receiving SIP messages at the SIP server from a communications network; processing the received SIP messages; detecting an overload based on a trigger condition as a result of receiving and processing SIP messages; and transitioning the SIP server to an overload state and applying appropriate control actions to mitigate the detected overload.

Abstract: The present invention provides methods for high throughput analysis of analytes in complex mixtures for unresolved chromatographic peaks including specific embodiment for summing intensities for each mass transition of interest over a selected chromatographic peak (50) to generate a signal corresponding to total intensity for each transition (55, 60). The intensities are deconvoluted into intensities of individual analytes (65, 70), based on branching ratios acquired from authentic standards, and a comparison to calibration curve is performed to obtain a quantitative concentration measurement of a particular analyte in a sample.

Abstract: A novel method for the qualitative and quantitative analysis of dicarboxylic acids in biological samples is provided. The method includes the steps of esterfying the acid component of the sample and subsequently analyzing the esterified sample using tandem mass spectroscopy using atmospheric pressure ionization techniques in the positive ion mode. The method is particularly useful in the determination of methylmalonic acid in biological samples, and thus, the diagnosis of vitamin B12 deficiency.

Abstract: A novel method for the qualitative and quantitative analysis of dicarboxylic acids in biological samples is provided. The method includes the steps of estering the acid component of the sample and subsequently analyzing the esterified sample using tandem mass spectroscopy using atmospheric pressure ionization techniques in the positive ion mode. The method is particularly useful in the determination of methylmalonic acid in biological samples, and thus, the diagnosis of vitamin B12 deficiency.

Abstract: A displacer assembly for a Stirling cycle system includes a displacer and a synchronous linear electric motor linked so as to drive the displacer. The electric motor features at least one stator assembly having first and second soft-magnetic pole pieces defining therebetween a gap. The width of the gap is oriented perpendicular to an axis of movement of the motor, and the stator assembly is constructed so as to generate a magnetic field aligned primarily parallel to the width of the gap. The motor also includes at least one compound permanent magnet system located within the gap. The compound permanent magnet system has a first section magnetized in a first direction parallel to the width of the gap and a second section axially displaced from the first section magnetized in a direction opposite to the first direction. The result of this structure is that the electric motor operates as a magnetic spring which, when no power is supplied to the motor, returns the displacer to a predefined rest position.

Abstract: A synchronous twin reciprocating piston apparatus includes a cylinder and a number of stator assemblies mounted in fixed relation thereto. The stator assemblies are constructed so as to generate a radial magnetic field in a number of regions near to each end of the cylinder. The apparatus also includes a pair of piston-magnet assemblies, each having a piston slidable within an end of the cylinder, and a number of compound permanent magnet systems located within the regions. Each compound permanent magnet system includes a first section magnetized in a direction radial relative to the cylinder axis and a second section, axially displaced from the first, magnetized in the opposite direction. When the stator assemblies are excited with an alternating current, the piston-magnet assemblies reciprocate axially relative to said cylinder, and synchronously with the frequency of the applied current. The pistons then generate a pulsating pressure within the cylinder.

Abstract: A piston-cylinder assembly in which the piston includes two piston heads connected together in spaced relation by a stem and cooperable with two portions of the cylinder, dividing the cylinder into a working chamber on one side of the first piston head between it and the end wall of the cylinder, a drive chamber on the opposite side of the second piston head communicating with the drive, and an intermediate chamber between the working chamber and drive chamber. The first piston head defines a clearance seal with respect to the first portion of the cylinder, and the second portion of the cylinder guides the reciprocatory movements of the piston. The intermediate chamber includes a semi-permeable seal between the cylinder and piston, which seal is permeable by gas but impermeable by liquids, to thereby prevent the passage of liquid from the drive chamber through the intermediate chamber to the working chamber.

Abstract: A piston-type compressor includes a cylinder having a liner sleeve in which is mounted a reciprocating piston driven by a crankshaft through a connecting rod. The piston forms a dynamic seal with the sleeve with the volume above the piston head defining a first, or compression chamber. Connected between the piston and the compressor cylinder is a flexible sealing element such as a bellows which defines a second, isolating chamber between the bellows and the dynamic seal and which further defines a third, or crankcase chamber between the bellows and the region of the compressor which includes the crankcase. The volumes in the second and third chambers are chosen so that the pressures therein are generally equal. A bypass filter assists in eliminating the pressure differential across the bellows during startup by maintaining the pressure within the intermediate and crankcase chambers substantially equal.

Abstract: A split Stirling cryogenic cooler including a compressor located in a first unit, and, located in a second unit, an expander-displacer defining an expansion volume, a cold tip adjacent the expansion volume, a regenerator heat exchanger and a displacer, a pneumatic conduit coupled the first unit to the second unit whereby pressurized gas pulses are provided from the compressor to the displacer for driving therof in oscillatory motion and apparatus for providing controllable damping of the resonant motion of the displacer comprising pneumatic flow produced friction damping apparatus.

Abstract: An integral Stirling cryogenic cooler including a compressor, an expander-displacer portion defining an expansion volume, a cold tip adjacent the expansion volume, a cold tip adjacent the expansion volume, a regenerator heat exchanger and a displacer, a crank shaft arranged to receive input rotary power and to drive the compressor and the displacer, and apparatus for low vibration mounting of the expander-displacer portion with respect to the compressor.