Showing papers on "Data acquisition published in 1981"

Addressable cable television control system with video format data transmission

Abstract: An addressable cable television control system controls television program and data signal transmission from a central station to a plurality of user stations. The data signals include both control and text signals in video line format which are inserted on the vertical interval of the television signals, thereby freeing all channels for transmission of both television and data signals. Moreover, full-channel teletext data in video line format may be transmitted on dedicated text channels with the modification of only head end processors. An intelligent converter at each remote user location uses the data signals to control access to the system on the basis of channel, tier of service, special event and program subject matter. The converter uses a graphics display generator to generate display signals for the presentation of the text data on the television receiver and for the generation of predetermined messages for the viewer concerning access, emergencies and other functions. The converter processes vertical interval text data and selected full-channel text data, both transmitted in video line format. The keyboard of the subscriber provides a number of different functional inputs for the subscriber to interface with the system. The converter also includes apparatus for interfacing with two-way interactive data acquisition and control systems.

Modular computer programs for flow cytometry and sorting: The LACEL system

Abstract: A computer-based data acquisition, display and processing system for flow cytometers has been developed. The Los Alamos Cell Analysis (LACEL) programs and electronic hardware provide the capability to acquire list mode or histogram data for up to eight parameters and control bidirectional sorting based on up to four parameters for each direction. The programs described in this paper also enable the display of single parameter and bivariate histograms and the graphical manipulation of the list mode data. The electronic hardware is described in a companion paper.

Point of manufacture data acquisition system

Abstract: A point-of-manufacture data acquisition system for an industrial facility including a series of work stations through which workpiece units are transferred, comprising a multiplicity of workpiece unit identification members, which may be punched data cards, each bearing scannable workpiece unit identification data, a number of similar production operation identification members, and a plurality of similar operator identification members. There is a data terminal for each work station. Each data terminal includes a simple, manually-operated data scanner; for punched card identification members, the data scanner comprises one LED and one phototransistor. The data terminal also includes a data store, a data display, and a microprocessor which controls entry and retrieval of data in the store and processes that data; each data terminal further includes program means controlling the sequence and acceptability of all data. A central polling processor periodically interrogates all data terminals to collect and record data. Two transmission lines and a ground line connect the polling processor to the data terminals; the transmission lines transmit DC power in opposite polarities to all data terminals on a shared-time basis with digital data signals transmitted to and from the polling processor; the data signals on each line are of opposite polarity from the power.

Modular electronics for flow cytometry and sorting: The LACEL system†‡§

Abstract: LACEL is a newly developed, fast, general-purpose data acquisition and processing system for flow cytometric applications. The system's modular electronics allows flexibility in system configurations. The system can process as many as eight input analog parameters and can transfer 16-bit words between the user's electronics and the computer with standard input/output interfaces. The system's 8-fold coincidence logic capability can be set to operate with the noncoincidental timing that may occur in multiparameter flow measurements. As many as four parameters can be used to establish amplitude and timing criteria for each of two sorting directions. Two experiments can be on line with the computer at one time.

X-ray tomography for microstructural objects.

Abstract: A high-resolution high-contrast x-ray tomography system for imaging the structure of submillimeter-sized objects is constructed. A precise data acquisition mechanism to realize a sharp pencil beam, use of an optimum x-ray band to achieve high contrast, deconvolution processing to restore blurred projections, and the iterative revision method to compensate for physically unavailable data are incorporated into the system. Basic experimental results obtained for an optical fiber used as a test object show that the system has ~20- μm spatial resolution and good adsorption coefficient discrimination.

Engine generated waveform analyzer

Abstract: An internal combustion engine analyzer provides both data acquisition and data processing and includes an analog waveform analysis subsystem together with a general purpose background system wherein appropriate power distribution is provided for the system as a whole and peripheral equipment such as a printer, keyboard and an analog/digital CRT is also provided. The input signals to be analyzed are waveforms generally associated with internal combustion engines and peripheral equipment. Exemplary waveforms are the primary and secondary ignition waveforms. The waveforms are attenuated to reasonable levels and multiplexed to analog circuitry which serves to measure waveform magnitude at one or more sampling points along the length of the wave and to also measure the manner in which the characteristics of the waveform change. The analog measurements are digitized and coupled to a processor which in turn controls the operation of the analog circuitry. The digitized measurements together with previously entered engine identification data are analyzed by the processor to thereby control subsequent data taking and to generate appropriate maintenance and repair instructions which are communicated visually to an operator in the disclosed embodiment.

The Vibroseis system; a high-frequency tool

Abstract: Exploration methods are extended to their limits as we continue the search for energy resources. Successful application of high-frequency seismic methods requires evaluating each element in the seismic acquisition system and ensuring that each part of the system contributes to the success of the method. This extends from seismic signal generation through data processing where good equipment performance and correct parameter selections are required.The Vibroseis system depends upon the ability of vibrators to generate synchronous, repeatable sweeps over the frequency range of interest. To support our high-frequency seismic efforts, Conoco Inc. has developed and built a new high-frequency vibrator. This paper includes some of the considerations used in building the vibrator, along with typical baseplate responses showing excellent drive levels to the design goal of 200 Hz. With an excellent source available, correct application is essential to assure retention of high-frequency data. Recording offsets, array lengths, and array sampling must be selected for the sweep frequencies used. Also, approximate matching of the data acquisition system response to the spectral response of the earth reduces the dynamic range requirements for recording systems and subsequent data processing. Data are included showing the successful application of high-frequency techniques to stratigraphic exploration problems.

Fast digital data acquisition and on-line processing system for an HB5 scanning transmission electron microscope

Abstract: The Fast Digital Data Acquisition System (FDDAS) links a Vacuum Generator’s HB5 Scanning Transmission Electron Microscope and a PDP‐11/34 minicomputer, to enable high‐speed collection and storage of digitized images for analysis, processing, and display, either in real time (using hardware) or later (via software). The FDDAS hardware consists of a digital scan generator, a programmable quad scaler with quad discriminator, an on‐line processor with digital gray level generator, an analog to digital converter, and a joystick. These devices are interconnected as addressable locations on the FDDAS bus line, the ’’System Bus,’’ on which they can act as data sources or sinks. The FDDAS also contains the circuitry for interfacing the system bus to the PDP‐11 UNIBUS, allowing it to read or write image data into the computer at memory cycle speeds. The FDDAS software consists of data transfer, data reformatting, and test pattern generation modules which are linked in an overlay structure and designed to execute under Digital Equipment Corporation’s RT11 operating system.

The XSYS Data Acquisition System at Triangle Universities Nuclear Laboratory

Abstract: We have described a general purpose data acquisition and analysis system for the VAX 11/780. The system runs under VMS and uses commercially available hardware for the bulk of the interface. The code is written almost exclusively in Fortran and uses many software components and ideas from other laboratories. All users share common versions of applications tasks, reducing problems associated with program proliferation and documentation.All event sorting is performed by the event analysis language EVAL. Singles data rates of about 70 KHz use about a third of the available CPU time. This has little or no impact on the response time for the other off-line users. Taking over work from an other facility is a convenient and fast way of implementing a data acquisition system when the computer and interface are identical. This was the case for us with the MBD software and the graphics software. If the hardware configuration is different, however, implementation may be difficult unless one of the programmers is very familiar with the system being installed. The key parts of our system, EVAL and the Z-like data structures, did require modification. They were developed during a three month visit by one of the authors (RVP). Once these foundations were laid, the work of writing the full system could be spread around a number of people. We estimate about 1.5 man years of effort in our system to date.

Design And Physical Characteristics Of A Digital Chest Unit

Abstract: A prototype digital chest unit capable of imaging patients in the conventional upright position is described. The unit employs a scanning slit configuration and discrete detector array. The general features of the detector and data acquisition system are discussed as well as the unit's physical performance parameters and geometry. The resolution along and transverse to the scanning direction is in agreement with theoretical predictions. Measurements of the digital chest unit's signal-to-noise ratio versus detector exposure, detector and data acquisition dynamic range, scatter transmission and exposure linearity are also discussed.

Seismic data acquisition method

Abstract: The field locations of seismic shot points are chosen to produce partial multifold data, the static correction equations of which are at least partially coupled. The seismic cross sections resulting therefrom are substantially improved.

Data acquisition and evaluation in biological monitoring systems

Abstract: Biological monitoring is a means of assessing the quality of water or wastewater One such method, which enables continuous and automated monitoring, assesses the ventilatory rates of fish as an early warning system The various methods for data acquisition and data analyses are discussed and compared

Microprocessors: Applications to Raman and Brillouin spectroscopy

Abstract: Automation techniques based upon the latest microprocessor computer technology are described in general terms for applications in light scattering spectroscopy. Two practical systems are described in detail. The first system operates a Raman spectrometer and handles the data collection automatically, storing the spectrum in digital form on disc and providing visual displays simultaneously. The second controls the alignment and scanning of a multi-pass Fabry-Perot spectrometer as well as data acquisition. Finally, prospects for future systems are reviewed.

Motor vehicle deceleration data acquisition and processing apparatus and methodology

Abstract: The decelerating movement of a vehicle during a skid test is sensed by an accelerometer which provides an analog signal representative of the deceleration to a computer where the analog signal is periodically sampled and converted into a digital deceleration signal for storing in a computer memory. Alternatively, the decelerating movement of the vehicle may be sensed by a radar speed detector providing digital signals representative of the initial speed and final speed of a time increment to a computer processor which records and stores the digital speed signals in computer memory to be later recalled to produce a digital deceleration signal. The computer processor effects storing of the digital deceleration signals in the computer memory at the beginning of a skid test when the magnitude of the signals exceeds a predetermined threshold level as sensed by a threshold level detector or, alternatively, when a mercury position switch is operated by the deceleration force. Subsequently, the stored deceleration data is retrieved from the computer memory by the processor for performing selected mathematical operations on the data to derive information such as the coefficient of friction encountered by the skidding vehicle, the length of the skid, and the time duration of the skid. The results of the mathematical operations may be displayed on a digital display panel or printed on a tape to provide a permanent record.

Experimental System For Dual Energy Scanned Projection Radiography

Abstract: Developing digital radiography techniques provides greater diagnostic information while utilizing less invasive procedures and/or decreased patient dose. An experimental scanned projection radiography system has been built using a CT detector and data acquisition system to provide increased contrast resolution and flexibility in data manipulation. Modifications to the basic system allow dual energy scanning, and subtraction algorithms relying on the energy dependence of the mass attenuation coefficient have been implemented.© (1981) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Apparatus for dynamic analysis of analog signals

Abstract: Apparatus for dynamic analysis of a plurality of analog electrical signals and particularly for fatigue analysis of a structure subject to mechanical stress, comprises a control module, and a data acquisition unit containing a plurality of data acquisition modules to which input analog signals from sensors are fed. Each data acquisition unit includes a specially arranged analog to digital converter, random access memory, microprocessor, programmable read- only memory, and input/output port communicating with the control module. The control module includes a microprocessor for control purposes, a programmable read-only memory, and input/output port communicating with the data acquisition modules for acquiring data therefrom and for sending control information thereto. A further input/output port on the control module allows communication with an external computer for further processing of acquired data. A battery ensures retention of data stored in memory in absence of main power supply.

Substation Interlocking and Sequence Switching Using a Digital Computer

Abstract: Power systems on-line control is being studied and applied for its technical and econcmical advantages. This paper presents the work carried out with a substation model, interfaced with digital processors for data acquisition and control, to develop and test on-line strategies to control switching operations. A network representation model containing switch data is scanned to forecast the effects of any switch operation providing a comprehensive and flexible inter-locking scheme. Extension of the concept to optimal sequence switching is also presented.

Low-Power Portable Geophysical Data Acquisition System And Its Use in Geomagnetic Measurements

Abstract: A low-power portable data acquisition system presently in use for geomagnetic measurements is described. The system is composed of a data-processing system containing a low-power microprocessor, a 9-track digital tape recorder, and a rechargeable battery pack. The magnetometer is a low-power three axis fluxgate design. Under program control the data processing system keeps track of time of day and date, samples three analog magnetometer outputs at intervals of either 0.4 or 2 s, digitizes the data to 15-bit resolution, and, depending upon relative magnetic activity, decides upon data compression to increase the tape storage capacity. It also monitors and records internal voltages and provides self-checking functions which may be monitored through a visual readout on the control panel. The system is mounted in a rugged, weather-tight carrying case suitable for use outdoors with minimal protection. The system, including magnetometer, uses 1.6-W power and can store 5.7 Mbytes of data.

The Data Acquisition System for the Neutron Scattering Instruments at the Intense Pulsed Neutron Source

Abstract: The Intense Pulsed Neutron Source (IPNS) at Argonne National Laboratory is a major new useroriented facility which is now coming on line for basic research in neutron scattering and neutron radiation damage. This paper describes the data acquisition system which will handle data acquisition and instrument control for the time-of-flight neutron scattering instruments at IPNS. This discussion covers the scientific and operational requirements for this system, and the system architecture that was chosen to satisfy these requirements. It also provides an overview of the current system implementation including brief descriptions of the hardware and software which have been developed.

Kinematic data acquisition system for two- or three-dimensional motion analysis.

Abstract: This paper presents a novel data acquisition svstem for motion analysis in two or three dimensions Emphasis is placed on a relatively simple method of data collecting requiring minimal equipment The system consists of an ordinary 35 mm camera (one camera for two dimensions or two cameras for analysis in three dimensions), infrared light emitting diodes (led) used as markers, and an electronic control circuit The camera records successive positions of pulsed infrared leds which are attached over anatomical landmarks, to produce sequences of dots on the film The resulting trajectories of the flashing diodes are digitised to generate numerical values which serve as input data to the computer carrying out the actual motion analysis

Design of the RSX11M Q System

Abstract: The present LAMPF Q data acquisition/analysis software system is being converted to run under the RSX-1lM operating system. Major subsystems have been redesigned to be compatible with RSX-11M and to provide enhanced functionality. In addition, two new major subsystems have been designed: a test package subsystem and a real-time parameter array subsystem.