Abstract: A personal inertial surveying system includes an inertial sensor and processing equipment adapted to be mounted to or carried by a person walking through a region being surveyed. As the person walks inaccuracies in position measurement due to drifts in the inertial sensor can be conveniently corrected. Corrections can be performed often during brief pauses as the person paces though the region, resulting in improved accuracy in the survey.

Abstract: Errors introduced into ac waveform measurements based on discrete amplitude samples because the waveform period is not an integral number of sampling intervals are substantially averaged out by computing the aggregate average of the set averages of sets of samples. Each set is taken over approximately an integral number of waveform cycles, and the set terminations are spread uniformly over approximately an integral number of cycles. Each set may overlap the previous set by all but one sample. As a short cut to the computation, each sample of the first set may be weighted with a weighting factor that is a respective member of an arithmetic series, starting at one and increasing in steps of one. Each remaining sample may be weighted by a factor that is a member of symmetrical series decreasing in steps of one and ending in one. The sum of all the weighted samples is accumulated and divided by the sum of all the weighting factors to produce the average of averages, or dc value of the waveform.

Abstract: An improved X-ray tomography system includes means for providing error information at each incremental angular position of the 360.degree. rotation of each scan, indicative of any mechanical lateral movements of the various tomography components during a scan, and means for compensating the data derived from the analog information signals representative of X-ray flux detected by the detectors during each projection view as a function of the error information during the back projection process so as to provide accurate scan data.

Abstract: In a hearing aid of the type having an electrical amplifier, wherein the improvement provides an audio signal processing circuit incorporated into the amplifier and including integral computing circuitry for controlling the operation thereof; the processing circuit providing circuitry for receiving an audio frequency electrical signal, circuitry for separating the audio frequency signal into a plurality of frequency bandwidths, circuitry for separately amplifying any audio frequency signal present in each of the bandwidths, circuitry for summing the amplified audio frequency signals from each of the bandwidths to produce a reconstituted signal, and circuitry for controlling amplification including circuitry for sampling any audio frequency signal present in each of the bandwidths and circuitry for determining, in response to the audio frequency signals sampled from all of the bandwidths the amplification level for each bandwidth for the separate amplification.

Abstract: A system for reducing a fixed number of data buses and connections in a computer system having a number of modules connected to the data bus utilizing the internal circuits of the various processing units or modules to transmit data from one unit to another via the data bus when the normal function of a unit can be interrupted, with the data routing and module control being under the control of a command bus.

Abstract: A composite signal is transmitted via a transmission line to an x, y, z display device. The composite signal contains in each of a plurality of predetermined time intervals an identifiable signal. The first signal of said composite signal is a synchronizing start signal. The other signals contain varying information. In the display device there are generated an x-, a y- and a z-coordinate signal. These coordinate signals are generated such that in said predetermined time intervals with reference to the synchronizing start signal and in predetermined varying combinations two of these three coordinate signals are developed and determined by the display device, whereas the remaining third coordinate signal is developed by the display device, but is determined from one of the other signals of the composite signal received via the transmission line.

Abstract: A signal processing apparatus comprises a main unit having a frame, and a plurality of modules for processing analog signals replaceably inserted into said frame. Each of the modules has an analog-to-digital converter for the analog signals and an identification signal generator which generates a module identification signal different for each module. The main unit comprises a signal processing system and a conversion pulse clock generator. The latter one clocks each analog-to-digital converter in each module to convert analog signals to digital data. The digital data are transmitted together with the module identification signal to the signal processing system.

Abstract: The apparatus contains a microprocessor circuit, which comprises a preprocessor which is not DMA-capable in itself and a DMA-capable central processor. Both processors can be made to communicate with each other by means of a main memory. This is performed by temporarily cutting off the communication path between said DMA-capable central processor and said main memory, specifically by an artificial DMA request via the address line of said preprocessor, and by establishing instead a communication path between said preprocessor and said main memory. The communication of said preprocessor with said main memory is started after said central processor has sent a return message signal to said preprocessor, whereby it confirms that its own communication with said main memory is completed.

Abstract: A cabinet is disclosed having recesses receiving sliding insulated plug-in modules, the modules having front connectors for receiving input signals and rear coupling portions, each module having printed circuit boards and a shield therefor.

Abstract: The system contains a number of monitoring devices, such as bedside units for monitoring parameters of patients, and a central station in star connection. Each monitoring device contains a signal generator and a display device for the display of monitored parameters. The central station contains a central display device and a central multiplexer. The multiplexer has a separate signal input for receiving the output signals of each signal generator, and a first and second number of multiplexer outputs. The output signals of the signal generators each contain undelayed and delayed signal data. The first multiplexer outputs can be connected to the central display device. Thereby, the undelayed signal data contained in the output signals of selected monitoring devices can be displayed in the central station. These signal data represent all parameters monitored by the selected device.

Abstract: A gating device which may be used with an image recording apparatus in connection with patient monitoring. The device gates a blanking bar with a recording of analogue signals on the picture screen of an oscilloscope.

Abstract: A tomography scanning system in which the intensity of radiation for each exposure is adjusted to obtain at the system detectors a minimum signal which results in a desired minimum signal-to-noise ratio to provide an image of acceptable quality with minimum radiation dosage to a patient.

Abstract: A tomography processor system for processing data from a plurality of projections in essentially real time to produce a reconstructed image immediately following completion of a scan. The system includes specialized high-speed processing stages for performing required calculations and operating in concert with a low-cost computer providing overall system control. These processing stages form a multi-stage pipeline processor capable of performing the correction, convolution, interpolation, and back projection functions required to reconstruct the desired final image. The invention makes use of a reconstruction algorithm particularly adapted to implementation in the manner disclosed and claimed.

Abstract: For use in an electronic weighing or force measuring system having a load cell providing an output signal representing measured force or weight, a ratiometric analog-to-digital converter operative with a low level differential input signal from the load cell and providing differential sensing of load cell excitation for use as a reference signal and generation of any required offset signal.

Abstract: An analog-to-digitial converter of the dual slope type wherein simultaneous integration of two input signals is achieved to provide a digital output substantially immune to disturbances affecting both signals. First and second dual slope converter circuits are employed, each receiving a respective analog signal. During conversion of the first signal, integration of the second signal is accomplished such that a digital output signal is provided representing the integrated instantaneous ratio of the two input signals and which is substantially free of disturbances affectng both of signals which may be introduced during a conversion cycle.

Abstract: For use in an electronic digitizer such as employed in an electronic weighing system, a circuit for detecting motion and providing a digital output signal. The circuitry includes a dual slope analog-to-digital converter having means for retaining a representation of the integrated analog level of a present and previous conversion cycle, the levels being representative of sampled data. The stored amplitudes are compared to provide an analog difference signal, and an output signal representative of measured weight is provided only when the difference signal is less than a predetermined reference threshold.