Abstract: A fluid dispensing system and method includes a pump to aspirate and expel sample fluid, a fluid dispensing tip, and a metering station. The fluid dispensing tip includes a working fluid and an air gap where the air gap separates the working fluid from the sample fluid. The metering station receives a drop of sample fluid that is at least twice as large as the pre-determined volume to ultimately be dispensed. The fluid dispensing tip then withdraws the predetermined volume of fluid from the sample fluid. Precise volumes are ascertained by prior knowledge of the geometry of the fluid dispensing tip and by using an imaging device to monitor an interface of either the sample fluid or working fluid with the air gap within the fluid dispensing tip. The system and method are capable of accurately dispensing very small volumes of sample fluid on the order of 10 picoliters. In addition, the system and method do not require large volumes of sample fluid to prime a pump mechanism.

Abstract: A fluid dispensing system and method includes a pump to aspirate and expel sample fluid, a fluid dispensing tip, and a metering station. The fluid dispensing tip includes a working fluid and an air gap where the air gap separates the working fluid from the sample fluid. The metering station receives a drop of sample fluid that is at least twice as large as the predetermined volume to ultimately be dispensed. The fluid dispensing tip then withdraws the predetermined volume of fluid from the sample fluid. Precise volumes are ascertained by prior knowledge of the geometry of the fluid dispensing tip and by using an imaging device to monitor an interface of either the sample fluid or working fluid with the air gap within the fluid dispensing tip. The system and method are capable of accurately dispensing very small volumes of sample fluid on the order of 10 picoliters. In addition, the system and method do not require large volumes of sample fluid to prime a pump mechanism.

Abstract: A fluid dispensing system and method includes a pump to aspirate and expel sample fluid, a fluid dispensing tip, and a metering station. The fluid dispensing tip includes a working fluid and an air gap where the air gap separates the working fluid from the sample fluid. The metering station receives a drop of sample fluid that is at least twice as large as the predetermined volume to ultimately be dispensed. The fluid dispensing tip then withdraws the predetermined volume of fluid from the sample fluid. Precise volumes are ascertained by prior knowledge of the geometry of the fluid dispensing tip and by using an imaging device to monitor an interface of either the sample fluid or working fluid with the air gap within the fluid dispensing tip. The system and method are capable of accurately dispensing very small volumes of sample fluid on the order of 10 picoliters. In addition, the system and method do not require large volumes of sample fluid to prime a pump mechanism.

Abstract: A fluid dispensing system and method includes a pump to aspirate and expel sample fluid, a fluid dispensing tip, and a metering station. The fluid dispensing tip includes a working fluid and an air gap where the air gap separates the working fluid from the sample fluid. The metering station receives a drop of sample fluid that is at least twice as large as the predetermined volume to ultimately be dispensed. The fluid dispensing tip then withdraws the predetermined volume of fluid from the sample fluid. Precise volumes are ascertained by prior knowledge of the geometry of the fluid dispensing tip and by using an imaging device to monitor an interface of either the sample fluid or working fluid with the air gap within the fluid dispensing tip. The system and method are capable of accurately dispensing very small volumes of sample fluid on the order of 10 picoliters. In addition, the system and method do not require large volumes of sample fluid to prime a pump mechanism.

Abstract: A fluid dispensing system and method includes a pump to aspirate and expel sample fluid, a fluid dispensing tip, and a metering station. The fluid dispensing tip includes a working fluid and an air gap where the air gap separates the working fluid from the sample fluid. The metering station receives a drop of sample fluid that is at least twice as large as the predetermined volume to ultimately be dispensed. The fluid dispensing tip then withdraws the predetermined volume of fluid from the sample fluid. Precise volumes are ascertained by prior knowledge of the geometry of the fluid dispensing tip and by using an imaging device to monitor an interface of either the sample fluid or working fluid with the air gap within the fluid dispensing tip. The system and method are capable of accurately dispensing very small volumes of sample fluid on the order of 10 picoliters. In addition, the system and method do not require large volumes of sample fluid to prime a pump mechanism.

Abstract: A fluid dispensing system and method includes a pump to aspirate and expel sample fluid, a fluid dispensing tip, and a metering station. The fluid dispensing tip includes a working fluid and an air gap where the air gap separates the working fluid from the sample fluid. The metering station receives a drop of sample fluid that is at least twice as large as the predetermined volume to ultimately be dispensed. The fluid dispensing tip then withdraws the predetermined volume of fluid from the sample fluid. Precise volumes are ascertained by prior knowledge of the geometry of the fluid dispensing tip and by using an imaging device to monitor an interface of either the sample fluid or working fluid with the air gap within the fluid dispensing tip. The system and method are capable of accurately dispensing very small volumes of sample fluid on the order of 10 picoliters. In addition, the system and method do not require large volumes of sample fluid to prime a pump mechanism.

Abstract: Method and apparatus for a railway navigation system which provides information defining the position of a railway vehicle on a track system. The system uses an on-board computer with a track database representing the locations of the rail lines, including locations of curves and switches. The system uses a turn rate indicator and a speedometer means to obtain a value for the curvature of the track on which the railway vehicle moves. Curvature data so obtained is compared with data in the track database to determine the position of the railway vehicle in relation to curves and switches of the track system.

Abstract: A surface energy meter (10) includes a probe (18) having two spaced apart electrodes (38 and 40) with a centrally located fluid dispensing head (36). When a fluid of known surface tension is dispensed onto a material (22) having unknown surface energy, the surface energy is determined by the volume of a fluid drop (42) which bridges between electrodes (38 and 40). The volume of the fluid drop (42) is closely regulated using a stepper motor (24) and by tracking the number of steps and volume dispensed per step required for the fluid drop (42) to expand to a point where the electrodes (38 and 40) are bridged. When a fluid of unknown surface tension is to be tested, materials having known surface energies are used.

Abstract: A plurality of lasers, each regulated to operate at a particular temperature, are supported by a manifold to direct coherent light into space. The regulation may be provided by producing pulses of a trickle current of a particular magnitude through the laser, measuring the voltage required to produce the trickle current and adjusting the characteristics of a thermoelectric member in accordance with the magnitude of such voltage to adjust the rate at which the thermoelectric member transfers heat from the laser. The lasers produce substantially parallel and thin beams of light in pairs. The light beams in each pair provide an optimum angle for the interception by such paired beams of particles having individual trajectories in space. These particles scatter the light to a receiving lens system disposed within the manifold. The received light then passes through masks which restrict the collected light to a spatial pattern corresponding to the pattern of the light beams from the lasers.

Abstract: Light from a moving airborne vehicle and scattered from atmospheric particles produces at first and second detectors at the vehicle, signals which are spatially and spectrally filtered, and conditioned by amplification and special filtering and converted to digital signals. The digital signals are edited and accepted if they satisfy certain conditions pertaining to a threshold variable with the average amplitude level of the noise plus signals. The digital signals from each particle are grouped. A centroid, based upon a weighting of the signals in each group with amplitude and time, is determined to represent the most probable time at which the particle crossed the peak of the illuminated region. The peak amplitude of each signal from the first detector is paired with the peak amplitude of the successive signals from the second detector. The time difference between the paired signals, and their product amplitudes, are determined.

Abstract: An imaging sonar system is disclosed comprising a transmitter, a receiver, and a rotatable transducer coupled with the transmitter and receiver for generating sound waves and for detecting echoes therefrom. Drive means are provided for rotating the rotatable transducer. Transducer position sensing means are provided for sensing the rotary position of the transducer. Analog to digital converter means are coupled with the receiver for converting receiver emitted signals into digital form. Serial access memory means are provided entering into storage receiver emitted signal data in digital form at a preselected rate and for withdrawing from storage receiver emitted signal data at a rate different than the predetermined rate. Write and read control means are also provided for respectively entering digital data into and recalling digital data from the memory.

Abstract: An electrical surge arrester tester comprising two surge arrester test leads and a voltage generator for generating and applying DC voltage of continuously increasing magnitudes to the surge arrester test leads. A monitor is provided for continuously and simultaneously monitoring the magnitude of DC voltages being applied to, and the current being conducted across, the surge arrester test leads. A counter is provided for digitally recording the monitored firing voltage when the monitored current exceeds a preselected magnitude. A terminator circuit is provided for terminating the generation and application of voltage by the voltage generator upon recording of the firing voltage. A digital display is also provided for displaying the digitally recorded firing voltage.