Small General-purpose Computer Research Articles

小型コンピュータによる眼球静電位図分析システム

This report presents an analogue data processing system, utilizing a small general purpose computer(HITAC E 600)for the electrooculography data reduction. The major characteristics of the system are as follows. 1. Whole process, from analogue-to-digital conversion to data processing can be put into practice interactively. 2. High operationability is attained by making use of process parameters file on disk. 3. Sufficient digital filtering is provided. 4. By using fast Fourier transformation, power spectra, coherence, and phase are calculated in a short time.

Time-of-day clocks and SKED: Techniques and applications

The SKED software system evolved as an attempt to replace traditional psychology laboratory instrumen­ tation with a small general-purpose computer (Snapper & Kadden, 1973). The system was written with tradi­ tional experimental designs in mind, and thus features were included to optimize experiments involving running small groups or individual subjects for short sessions each day. The notational system that forms the basis for the SKED language, however, is considerably more general in scope (Snapper, Knapp, & Kushner, 1970), and can easily describe procedures requiring more extended experimental sessions. The present modifications to SKED arose from requirements to control experimental environments in which the subjects lived for the duration of the ex­ periment. Control of behavior in continuous experi­ mental environments is not fundamentally different from that required for shorter experimental sessions. However, it becomes necessary to have a means of synchronizing the experiment with the clock. While earlier versions of SKED could perform these functions, it was necessary to have the program for each experi­ mental station keep track of the clock time and to have a means of initializing the time for each station. This involved considerable waste of computer time and memory, and led to the development of time-of-day clocks described in this paper, which could be in­ corporated into the SKED monitor and accessed as required by individual experiments. Two different techniques have been developed for maintaining time-of-day information in SKED. Both systems perform the functions of maintaining locations in memory containing the current hour (0-23), the current minute (0-59), and the current 24-h time (0-2359). Assembly language subroutines (F3 routines) incorporated in the SKED monitor can be called from SKED programs to control program operation based on

On-line training on analog computer identification of a speed control system

This paper investigates a method for modelling a speed control system through the use of a small general-purpose analog computer. Sensitivity functions are utilised to identify the model parameters. The time response of the system is compared with a reduced analog model. The transient error response and outputs from a comodel are used in predicting the model parameters. Theoretical and experimental work are presented and the identification algorithm is explained.

A High Speed Microprogrammed System for Generation and Acquisition of Signals

A high speed microprogrammed system has been constructed to perform the synthesis and recording of high frequency nonrepeating pulse signals. The system can drive an analog device with arbitrarily designed waveforms and record individual pulses from several sensors in return. The present design operates at frequencies up to 1.5 MHz and can accept pulse durations of up to 16 000 samples. Accuracy is limited by the availabe ADC and computer word size and is presently 8 bits (0.3%). A primary advantage of the design is the reliance to the maximum extent on the hardware of a small general purpose computer. Very little more external hardware is required than the ADC, DAC, and multiplexer. Waveforms are read directly from and stored directly in the host computer core memory. This enables the maximum flexibility in the design of service programs for particular experiments. At present the system is used for an experiment in which a fast pulse input is to be adjusted adaptively in real time based on the measured outputs of a system.

Principles of automatic analysis of sleep records with a hybrid system

A program for automatic sleep staging of whole nights polygraphic records of human subjects is described. The electronic system consists of an analog component, performing a first reduction of data, and a digital one, a small general purpose computer. The computer program assesses first the technical quality of the record, by recognition of artefacts, which may impair the diagnosis procedure. It performs second a two steps analysis, based upon electroencephalogram, muscle activity and eye movements. The first step of analysis is a recognition of elementary patterns on the tape and the second step is a calculation of a minute by minute sleep stage diagnosis, based upon these elementary patterns. This program has been tested by comparisons with human scoring of the same records, and has proved to have a good accuracy. This system is actually used as a clinical tool in the exploration of sleep disturbances.

A computer-controlled electron-beam machine for microcircuit fabrication

The main advantages of electron-beam methods for the fabrication of microcircuits are: 1) improvement in resolution; and 2) ease of automation. A computer-controlled electron-beam machine has been developed from a high-resolution scanning electron microscope and has incorporated several important features for use in microfabrication, such as an LaB 6 gun to improve brightness and stability, and a special electron collection system based on channel multipliers, which is particularly suitable for use with large flat specimens. The control system is based on a small general-purpose computer with a flexible data input facility which can be made compatible with the output of most computer-aided mask design facilities. The input data is based upon rectangular shapes but additional nonrectangular shapes can also be handled. Several of the important technical areas of the machine have been evaluated, e.g., resolution, speed of operation, area of coverage, etc. It has been found that speed of operation and area of coverage are both related to the beam diameter used and the effect of this rather complicated interrelationship has been studied. The machine has been used to generate patterns on mask and wafers and results indicate that it has direct application to microcircuit manufacturing and one immediate use would be to develop it into a mask maker where it could produce a complete set of standard size masks (1x) in one working day.

A computerized system for rapid evaluation of thyroid function.

To improve the accuracy and speed of determination of thyroid structure and function, we have developed a system that combines the use of 99mTc-pertechnetate, the scintillation camera and a small general-purpose computer. With the pinhole collimator of the gamma camera over the patient's thyroid, five mCi of 99mTc-pertechnetate is injected intravenously. Data are accumulated in the core memory of an Image Display and Analysis System (“IDA”). The activity of a standard amount of 99mTc in a thyroid phantom is also measured. Data are displayed as serial images on a video screen. The exact area and activity of the thyroid are then computed by simple programs used together with a light-pen. The activity in tissue adjacent to the thyroid is subtracted to correct for extrathyroidal activity. The entire gland and focal regions within the gland are characterized by rates of uptake of 99mTc-pertechnetate. The method was tested with respect to variations in the size, position and activity of the thyroid. There was g...

SMART - A three-axis stabilized attitude reference technique.

An autonomous star mapping attitude reference technique (SMART) suitable for providing three-axis attitude information is discussed. The paper examines the possibility of utilizing one field of view and only two stars to provide three-axis attitude information. The star field is examined for a uniqueness criterion based on the resolution of a star mapper. The system utilizes an electronic scanning star mapper and a small general purpose computer— thus no moving parts are utilized. The technique applies either to inertially stabilized or slowly spinning spacecraft. The star field is shown to be suitable for such a system provided the star mapper field of view is properly oriented with respect to mission orbital parameters or multiple mappers are utilized. Maps of star pair availability for star mapper fields of view of 20° and 40° are included. An estimate of the total attitude error based on star mapper accuracy is given. The system is capable of performing continuous attitude determination if the mission orbital parameters are sufficiently restrained or multiple mappers are utilized. The system may also be used to automatically update an inertial system for missions where the orbital parameters preclude the use of a single mapper.

An off‐line system for data acquisition and analysis

AbstractA generalized solution to the problem of laboratory data acquisition and data reduction will be discussed. The Nuclear Data 7700 System represents a new approach to laboratory data acquisition and reduction in that it is capable of interfacing with, providing complete data analysis and generating comprehensive output reports for many instruments in the analytical laboratory. Featuring both off‐line data reduction and digital magnetic tape cartridge program storage, it was designed to offer an economical and minimum obsolescence solution to the data reduction problem. The system allows the full capability of a small general purpose computer to be employed with a variety of computer programs to perform data analysis for a variety of instruments. Besides software availability, providing complete data reduction and comprehensive output reports, for the more important analytical instruments such as Gas Chromatographs, IR and Atomic Absorption Spectrophotometers, Physical Testing Instruments, etc., the flexibility of this approach makes computerized data reduction practical for such instruments as Thermal Analyzers, Titrators, etc. The gas chromatography data handling aspects of the system are discussed in detail.

A digital computer data acquisition, display, and analysis system for the gamma camera.

A digital computer data acquisition, display, and analysis system for use with a scintillation camera is described. The system makes possible quantitative analysis of a scan image now represented by a 50 × 50 matrix. The low cost of the small general-purpose computer employed in this system makes it a practical consideration for the average nuclear medicine laboratory.

The use of a high resolution NMR spectrometer controlled by a dedicated computer for quantitative analytical chemistry.

AbstractOperational complexity of high resolution NMR spectrometers has severely limited their use in quantitative analysis in spite of the many inherent advantages of the NMR technique. In order to demonstrate the feasibility of routine analyses in a rapid and accurate fashion with no special demands on the skill of the operator, the authors have programmed a small general purpose computer to control an NMR spectrometer, maintain adjustment of critical operating parameters, acquire data, numerically integrate appropriate spectral regions, calculate results and errors, and print out a teletype record of results. The unsaturation in natural edible oils, expressed as the iodine number and a polyunsaturation factor, has been chosen to illustrate in a specific case the application of this general approach to the analysis of multicomponent mixtures. It is shown in this paper that iodine numbers obtained by NMR agree with those obtained by the classical titration method within two or three iodine numbers over a wide range of values. The effect of varying NMR instrumental parameter settings over a wide range has also been investigated and reported. In view of the results obtained in the present work, it appears that computers aided quantitative analysis using sophisticated analytical instrumentation such as NMR spectrometers, and should now be given serious consideration by many high volume, multicomponent analyses in the food, drug and chemical industries.

A teaching program for experimentation with computer-assisted instruction

Although many perspicacious mathematics teachers are interested in learning more about computer-assisted in struction (CAI), the high costs and relative inaccessibility1 of these sophisticated systems have afforded little opportunity for firsthand experience with this technological advance which will surely have far-reaching effects on education. Recently, however, a program has been developed which will “convert” a small general-purpose computer, available at many schools and campuses, to an electronic teaching machine capable of teaching skill s with facts of both multiplication and addition.2 Furthermore, the author wishes to announce th at this program is available to readers of The Arithmetic Teacher. It is hoped that the dissemination of this program will lead to improved pupil achievement, increa ed teacher and parental interest in innovation, and the enhancement of research opportunities in other places as it has at Indiana State University.

A Digital Control Laboratory

A laboratory facility is described that provides for the experimental study of digital control systems. The activities of the laboratory are designed to permit experiments in data conversion, data acquisition, hybrid system simulation, computer control of typical physical processes, and binary and decimal data transfer between a digital computer and peripheral equipment. The main facility of the laboratory is a PDP-8 computer, a small general-purpose computer. The laboratory program is part of an educational program in the study of discrete systems and computer control system. This program is also briefly described.

Use of ``On Line'' Computer for Mössbauer Experiments

The application of a small general purpose computer as an ``on line'' data acquisition device for Mössbauer effect experiments is described. A method of conversion from analog to digital information and an outline of the computer program are given. The performance of the system is demonstrated by a Mössbauer spectrum of iron sulphide (pyrite). The extension of these techniques to other experiments is briefly considered.

N17Energy Levels and Gamma Rays

The nuclear reaction ${\mathrm{Li}}^{7}$+${\mathrm{B}}^{11}$ was studied with the use of a three-parameter analysis technique. The three parameters recorded were particle type, particle energy, and energy of gamma rays in time coincidence with the charged particles. Both ungated particle spectra and particle-gamma-ray coincidence data were taken simultaneously. Particles were detected by a $E\ensuremath{-}\frac{\mathrm{dE}}{\mathrm{dX}}$ system made up of solid-state detectors. The gamma rays were detected in a large NaI (Tl) crystal. The data gathering and analyzing system consisted of three pulse-height analyzers (256 channels for ${E}_{\ensuremath{\gamma}}$ and $\ensuremath{\Delta}E$, and 1024 channels for ${E}_{\mathrm{particle}}$), and a small general-purpose computer with magnetic tape units and an oscilliscope display. The energies of protons from the reaction ${\mathrm{B}}^{11}({\mathrm{Li}}^{7}, p){\mathrm{N}}^{17}$ were measured. Groups corresponding to previously observed states in ${\mathrm{N}}^{17}$ were seen as well as 14 new states. Spectra of gamma rays from the bound levels of ${\mathrm{N}}^{17}$ were analyzed to give the decay schemes and some branching ratios. Calibrations were obtained from gamma rays of known energy produced in the reaction and from the known energies of some of the proton, deuteron, and triton groups.

The NRL Cyclotron Data Acquisition and Processing System

In order to make effective use of the NRL Isochronous Cyclotron we are designing an efficient multipurpose data collection and data handling facility. The central part of this system is a small general purpose computer with all digital data collection devices (examples are: timers, scalers, frequency meters, and digital voltmeters) feeding directly into the computer, thus eliminating a vast amount of time-consuming and error-causing paper work. The computer will also be used for multi-parameter and single-parameter multichannel analysis with ADC's feeding the computer memory directly. For rapid display of data, and any desired graphical display, a computer controlled CRT display will be used. A light pen will be used to select and modify information in the computer memory. The standard input-output equipment will consist of a typewriter, paper tape read/punch unit, two magnetic tape units, a graph plotter, and a fast on-line printer. The on-line time will be time shared between the (random) data collection and data processing and/or display. To make such concurrent operations possible a priority interrupt system will be used, with a higher priority system taking over computer control from a lower priority operation.

Computer-Controlled Automated Testing on the Polaris Program

Recently there has been increased interest in the use of computer-controlled testing equipment at static test facilities and prelaunch checkout areas as well as at manufacturing locations. LMSC has designed, built and operated such a system for over two and one half years. During the early phases of the Polaris program, an impending need was already apparent. The anticipated high rates of production would require extensive personnel and equipment for system and subsystem testing. Could automation alleviate this problem within reasonable economic limits? Also, sought was a quality of testing consistent with the degree of reliability being designed into the missile, and a means for providing accurate and reliable test data for design-improvement feedback and missile system reliability analysis. Lockheed design personnel felt strongly that the solution to these problems was a flexible automated testing system under the control of a stored program general purpose digital computer but it was necessary to minimize the cost of the control computer. Two steps were taken to accomplish this: A small test-oriented drum memory general purpose computer was designed and built by Lockheed, and a most significant advancement for that day, the testing system was organized so that one computer could be time shared among eight testing stations. The digital computer, located in a central control set, controls the operation of remote test consoles and automatically evaluates missile systems, subsystems and modules.