Computerized Data Acquisition Systems Research Articles

Processor control in computerized data-acquisition systems

A method is proposed for detecting single and double processor errors during arithmetic and logicaloperations with reduced time consumption.

Functional code error monitoring in computerized data-acquisition systems

Functional code error monitoring in computerized data-acquisition systems

Multiparameter Measurement Systems

An accuracy criterion is used in the synthesis of multiparameter computerized data-acquisition systems.

Computerized analysis of isometric tension studies provides important additional information about vasomotor activity.

Concentration-response curves of isometric tension studies on isolated blood vessels are obtained traditionally. Although parameters such as Imax, EC50 and pA2 may be readily calculated, this method does not provide information on the temporal profile of the responses or the actual nature of the reaction curves. Computerized data acquisition systems can be used to obtain average data that represent a new source of otherwise inaccessible information, since early and late responses may be observed separately in detail.

Data Acquisition Systems for Fusion Devices

During the last two decades, computerized data acquisition systems (DASs) have been applied at magnetic confinement fusion devices. Present-day data acquisition is done by means of distributed computer systems and transient recorders in CAMAC systems. The development of DASs has been technology driven; the emphasis has been on the development of computer hardware and system software. For future DASs, challenging problems are to be solved. The DASs have to be better optimized with respect to the needs of the users. Existing bottlenecks, such as CAMAC-computer coupling or pulse file merging, need to be eliminated. Continuous or long-pulse operation will require the introduction of event abstraction in DAS design.

FDA's good laboratory practice regulations and computerized data acquisition systems

Lepore, P.D., 1992. FDA's good laboratory practice regulations and computerized data acquisition systems. Chemometrics and Intelligent Laboratory Systems: Laboratory Information Management Systems, 17: 283–287. The Food and Drug Administration's good laboratory practice regulations apply to computerized systems that are used to collect and process data deriving from a non-clinical laboratory study. Such systems are considered to be ‘equipment’ and are regulated similarly to other equipment used in a laboratory. In this regard, computerized systems are to be of appropriate design and adequate capacity to accomplish protocol directions, and their fitness for use in a study is to be documented. Written, approved standard operating procedures are to cover system testing, calibration, standardization, inspection, and maintenance, and a historical file is to contain a listing of versions and dates of implementation. The system is to accommodate the identification of each individual responsible for direct data entry at the time of entry. Data entries may be changed but an audit trail must preserve the original entry and identify the person making the change, list the date of the change, and provide a reason for the change. In view of the forgoing, FDA's inspections of computerized systems are designed to determine whether the systems operated properly in the past, whether they are currently operating properly, and whether they will continue to operate properly in the future. A satisfactory outcome can best be achieved through the development, installation, use, and maintenance of systems comporting with high quality standards.

An Experimental Appraisal of the Load-Deformation Properties of A325 High-Strength Bolts

Abstract Current specifications and testing procedures of high-strength bolts are based on the results of early research performed in the late 1950s and the early 1960s using the testing technology available at that time. Within the past few decades, the development of new, advanced testing equipment and computerized data acquisition systems has brought about significantly improved capabilities for materials testing. In light of these advancements, conducting a new set of bolt tests was considered essential in appraising the load deformation properties of high-strength bolts using the new testing technology. In this study, samples of randomly obtained A325 high-strength bolts were tested in accordance with the ASTM standard test methods, utilizing a servo controlled universal testing machine and a computerized data acquisition system. This equipment differs from that used in the early research in the accuracy of the data collected and the existence of many available options for specimen loading. The new testing technology provides an easy determination of the yield point, the proof load, and ductility of the bolts. The study aimed at experimentally determining the load-deformation properties of high-strength bolts and comparing them with those generated by early research. The proof load, the yield strength, and the teasile strength obtained were much higher than the specified ASTM and AISC values. Additional studies were pursued to gain an improved understanding of the behavior of the bolts as affected by the exposed thread length in the grip. The tested bolts showed higher strength and lower ductility as the number of the thread exposed in the grip length decreased.

Very low current amplifier for computerized data acquisition systems in noisy environments

A routine requirement in experiments on synchrotron light sources is the measurement of the currents generated by photoemission. Accurate recording of such low level signals is often problematic due to electronically noisy environments and the distance between the data acquisition computer and the experiment. We present the design of a low current amplifier whose small size enables it to be mounted directly onto the experimental chamber. The device generates a frequency output proportional to its input signal. This method of frequency transmission ensures a high level of noise immunity and permits the use of standard counting electronics. Multiple devices may be driven from a common clock, derived from the counter clock, thus eliminating errors due to clock frequency drift.

Fatigue crack propagation in unplasticized poly(vinyl chloride): 1. Effect of mean stress

Abstract The effect of mean stress on fatigue crack growth in an unplasticized poly(vinyl chloride) (uPVC) pipe material was investigated using single-edge-notched (SEN) specimens and the results analysed in terms of fracture mechanics. Three series of experiments were conducted. In the first the fatigue crack growth rates d a d N were collected as a function of the applied stress intensity factor range ΔK (= K max − K min ) by keeping the stress ratio R(= K min K max ) constant. In the second series of experiments d a d N were obtained as a function of ΔK when the mean stress intensity factor K m was constant; and in the third series ΔK was maintained constant, d a d N were obtained with increasing K m . All experimental results were obtained and processed using computerized data acquisition systems. When the data were analysed in terms of the conventional log d a d N versus log ΔK and log K m plots the effects of R and K m on fatigue crack growth rate were insignificant. However, there was a strong dependence of d a d N on R when analysed in terms of Williams' line zone model for fatigue crack growth.

Authors

Authors

Review of the 3rd Biennial Conference on Real-Time Computer Applications in Nuclear and Particle Physics

The community of engineers, programmers, and physicists who support data-acquisition, control, and post processing activities in nuclear and particle physics had an opportunity to meet in Berkeley on May 16-20, 1983 for the on Real-Time Computer Applications.... It was the third such conference, held every other year. In May, 1979 Dennis Perry of Los Alamos Scientific Laboratory hosted the Topical Conference on Computerized Data-Acquisition Systems in Particle and Nuclear Physics in Santa Fe. David Hensley brought the conference to Oak Ridge in May, 1981. And this year's conference underwent a name change by it's host, Creve Maples of Lawrence Berkeley Laboratory, but remained very much the same in spirit and direction.

Computerized Data Acquisition Systems for Dairy Herd Management

Computerized Data Acquisition Systems for Dairy Herd Management

Topical Conference on Computerized Data-Acquisition Systems in Particle and Nuclear Physics 14-17 May 1979, Santa Fe, New Mexico

Topical Conference on Computerized Data-Acquisition Systems in Particle and Nuclear Physics 14-17 May 1979, Santa Fe, New Mexico

THE LOWELL OBSERVATORY DATA SYSTEM

ABSTRACT Two computerized data-acquisition systems have been designed and built at the Lowell Observatory. These systems, which are centered around the PDP-1 1 minicomputer, embody the following design concepts. 1. Software development is a large and continuing task. Everything possible should be done to facilitate this part of the development. 2. A keyboard is used for all manual data entry, which eliminates the need to interface to a large number of switches. 3. A cathode -ray 4ube display is used to achieve good communication between the astronomer and the system. 4. A highly reliable magnetic tape unit (DECTAPE) is used for storage of programs and data, which has increased the ease and speed of program development. 5. The computer has many desirable features, plus enough core (8K) to make programming relatively easy and rapid. 6. The entire system is under the control of a real-time monitor program. 7. All input-output is done in the background by the monitor program, which utilizes the advanced interrupt structure available on this machine. 8. The programming has been made extremely modular to facilitate further program development. The necessary hardware and software have been developed within six months, and the systems are now in use at the telescope. In two programs involving rapid scanning we have realized a six-fold gain in the efficiency of data taking. Further gains are anticipated as more sophisticated programs of data analysis become available at the telescope. Key words: instrumentation - data-aequisition system - computer