Science Applications International Corporation

The United States of America As Represented by the United States

Martin Marietta Energy Systems, Inc.

Other

The United States of America As Represented by the United States Energy

Kenneth H Valentine

Victor V Verbinski

Victor J Orphan

Scott T Smith

Manfred K Kopp

John M Wettroth

Melvin G Willey

Ernest L Long, Jr

Eric Ackermann

Jeff Adams

Michael E Buchanan

Diedre D Falter

Howard T Kerr

Kelly G Falter

A system and method of density detection in a target object involve irradiating the target object, detecting a first and second discrete number of photons penetrating the target object through respective first and second prescribed volumes and entering respective first and second radiation detectors. First and second numbers of photons detected by the first and second radiation detectors are counted, and a display output signal is generated in response to the first and second numbers. A graphical representation of the densities within the first and second volumes of the target object is displayed.

Density detection using discrete photon counting

A system for detecting and graphically displaying a contents of a fast-moving target object comprises: a radiation source, having a position such that at least a portion of radiation emitted from the radiation source passes through the fast-moving target object, the fast-moving target object having a variable velocity and acceleration while maintaining a substantially constant distance from the radiation source and being selected from the group consisting of: a vehicle, a cargo container and a railroad car; a velocity measuring device configured to measure the variable velocity of the fast-moving target object; a detector array comprising a plurality of photon detectors, having a position such that at least some of the at least a portion of the radiation passing through the target object is received thereby, the detector array having a variable count time according to the variable velocity and a grid unit size; a counter circuit coupled to the detector array for discretely counting a number of photons entering individual photon detectors, the counter circuit measuring a count rate according to a contents within the fast-moving target object; a high baud-rate interface coupled to the counter circuit for sending count information from the counter circuit at a rate fast enough to support real-time data transfer therethrough; and a processor coupled to the velocity measuring device and to the high baud-rate interface, receiving count information from the high baud-rate interface and generating distortion-free image data in real time as a function of the count information and the variable velocity. A method for using the system is also disclosed.

Density detection using real time discrete photon counting for fast moving targets

A radiation measurement apparatus and method extends the measurement range of a single Geiger Mueller tube (GMT). The apparatus may operate in a either a conventional mode, used to measure low radiation levels, e.g. background radiation, or an extended range geiger (ERG) mode, used to measure high radiation levels. Both modes utilize the same GMT and basic operating circuitry, including a power supply for generating a GMT anode voltage, a GMT anode voltage control circuit, a GMT trigger circuit, a clock circuit, and a GMT pulse counter circuit. In the conventional mode, the radiation rate is determined as a function of the number of GMT pulses counted over a prescribed time period. In the ERG mode, an additional counter is employed to count trial intervals of a prescribed duration. The radiation rate is determined in the ERG mode statistically as a function of the ratio of the GMT pulse count and the trial interval count, with a prescribed number of trial interval counts being rejected after each GMT pulse in order to assure known initial conditions.

Extended range geiger counting apparatus and method utilizing a single

Small, light-weight portable radiation measurement apparatus provides accurate quantitative measurment of radiation dosage and dosage rates. Such apparatus, referred to as a dosimeter, is housed in a ruggedized housing that is only about 1/2 the volume of a package of cigarettes, may easily be clipped to clothing or carried in a shirt pocket, and is powered by a conventional alkaline AA-sized battery. Included in the housing are a geiger tube for detecting radiation, a high voltage power supply for providing power to the geiger tube, a counting circuit for counting geiger pulses generated by the geiger tube, a microprocessor circuit for processing the geiger pulses in accordance with a prescribed program to determine the does or dosage rate to which the geiger tube has been exposed, and a digital display that displays the dosage rates thus determined. The microprocessor program is stored in memory circuits, included as part of the microprocessor circuit. An audible alarm is generated whenever the dose or dosage rate exceeds a programmable threshold. The circuitry and display allow a wide range of radiation levels to be detected and displayed. All the circuits are designed for low power consumption, allowing 500-600 hours of continuous use before having to replace the battery. A dielectrically coupled communications port allows necessary data, e.g., calibration coefficients or dosage data, to be transferred to and from the dosimeter circuitry without direct physical contact.

Electronic pocket dosimeter

A system for monitoring moving objects, such as the flight of honeybees and other insects, using a pulsed laser light source. This system has a self-powered micro-miniaturized transmitting unit powered, in the preferred embodiment, with an array solar cells. This transmitting unit is attached to the object to be monitored. These solar cells provide current to a storage energy capacitor to produce, for example, five volts for the operation of the transmitter. In the simplest embodiment, the voltage on the capacitor operates a pulse generator to provide a pulsed energizing signal to one or more very small laser diodes. The pulsed light is then received at a receiving base station using substantially standard means which converts the light to an electrical signal for processing in a microprocessor to create the information as to the movement of the object. In the case of a unit for monitoring honeybees and other insects, the transmitting unit weighs less than 50 mg, and has a size no larger than 1.times.3.times.5 millimeters. Also, the preferred embodiment provides for the coding of the light to uniquely identify the particular transmitting unit that is being monitored. A 'wake-up' circuit is provided in the preferred embodiment whereby there is no transmission until the voltage on the capacitor has exceeded a pre-set threshold. Various other uses of the motion-detection system are described.

Infrared system for monitoring movement of objects

A method and device have been provided for distinguishing Africanized honeybees from European honeybees. The method is based on the discovery of a distinct difference in the acoustical signatures of these two species of honeybees in flight. The European honeybee signature has a fundamental power peak in the 210 to 240 Hz range while the Africanized honeybee signature has a fundamental power peak in the 260 to 290 Hz range. The acoustic signal produced by honeybees is analyzed by means of a detecting device to quickly determine the honeybee species through the detection of the presence of frequencies in one of these distinct ranges. The device includes a microphone for acoustical signal detection which feeds the detected signal into a frequency analyzer which is designed to detect the presence of either of the known fundamental wingbeat frequencies unique to the acoustical signatures of these species as an indication of the identity of the species and indicate the species identity on a readout device.

Method and device for identifying different species of honeybees

An extended range dose-rate monitor is provided which utilizes the pulse pileup phenomenon that occurs in conventional counting systems to alter the dynamic response of the system to extend the dose-rate counting range. The current pulses from a solid-state detector generated by radiation events are amplified and shaped prior to applying the pulses to the input of a comparator. The comparator generates one logic pulse for each input pulse which exceeds the comparator reference threshold. These pulses are integrated and applied to a meter calibrated to indicate the measured dose-rate in response to the integrator output. A portion of the output signal from the integrator is fed back to vary the comparator reference threshold in proportion to the output count rate to extend the sensitive dynamic detection range by delaying the asymptotic approach of the integrator output toward full scale as measured by the meter.

Extended range radiation dose-rate monitor

A neutron flux monitor is provided which consists of a plurality of fission counters arranged as spaced-apart point detectors along a delay line. As a fission event occurs in any one of the counters, two delayed current pulses are generated at the output of the delay line. The time separation of the pulses identifies the counter in which the particular fission event occured. Neutron flux profiles of reactor cores can be more accurately measured as a result.

Neutron flux profile monitor for use in a fission reactor

An atomic fission counting apparatus used for neutron detection is provided with spirally curved electrode plates uniformly spaced apart in a circular array and coated with fissile material.

Neutron detection apparatus

A gamma analyzer system is provided for the analysis of nuclear fuel microspheres and other radioactive particles. The system consists of an analysis turntable with means for loading, in sequence, a plurality of stations within the turntable; a gamma ray detector for determining the spectrum of a sample in one section; means for analyzing the spectrum; and a receiver turntable to collect the analyzed material in stations according to the spectrum analysis. Accordingly, particles may be sorted according to their quality; e.g., fuel particles with fractured coatings may be separated from those that are not fractured, or according to other properties.

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San Diego, CA, United States of America

Kenneth H Valentine