Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Computer Systems”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 397 records · Page 22Linked to original sources
PubMed1982

Neuron reconstruction using a Quantimet image analyzing computer system.

A PDP-11/34 laboratory computer, a Quantimet image analyzer, and a research light microscope with motorized X, Y stage and focus axis are used for "semi-automatic" neuron reconstruction. The operator examines each neuron tree through the microscope eyepieces, commands the Quantimet system to move the stage and focus the optics, and when a point along the neuron process is in focus under a cross-hairs, commands the PDP-11 computer to record the point's spatial coordinate. A list of such coordinates when stored in the PDP-11 forms a mathematical reconstruction of the neuron. Because the Quantimet system was not designed for this type of work, there may arise some problems when using it. Incremental microscope stage movements are difficult to produce; its display does not accurately depict neurons; its software does not facilitate the simple commands to the microscope motors required in neuron reconstruction. Despite these constraints, a neuron tracing system has been written which traces and statistically analyzes neurons.

Animals↗
PubMed1998

Orthographic codes are used in integrating information from the parafovea by the saccadic computation system.

Two experiments that examined the characteristics of information extracted from a parafoveal letter string by the saccadic system are reported. In Experiment 1, we observed the effect of the orthographic legality of the initial letter sequence on landing positions. The deviation of landing positions towards an orthographically illegal letter sequence was shown to occur in saccades when subjects were instructed to read a nonsense letter string. Moreover, it was shown that the initial placement of the eyes is influenced by the frequency of occurrence of the letter sequence and not by the frequency of the letters that formed this sequence. Experiment 2 followed up on the implication that readers use orthographic information only from the initial letters of the parafoveal string. We concluded that the saccadic computation system integrates orthographic information from the two initial letters.

Analysis of Variance↗
PubMed2000

Facial-motion analysis with a video and computer system: a preliminary report.

HYPOTHESIS: To investigate the feasibility of a video and computer-assisted system for evaluating the temporal and spatial aspects of facial motion during selected facial expressions in a pilot group of six normal adults. Evaluation of the diverse medical and surgical treatments for facial paralysis and paresis cannot occur until objective, reliable, and sensitive measures of the spatial and temporal aspects of facial function at specific facial landmarks are developed. METHODS: Facial motion at predetermined facial locations was assessed using a commercially available computer-interactive motion analysis system, which is based on videography principles. The displacement, velocity, and acceleration data were averaged across all trials and subjects. Time plots also were obtained for the left versus right side. RESULTS: The greatest mean maximum displacement (resultant vector) occurred during the eyebrow lift expression, reaching 1.2 cm in magnitude. The mean maximum velocity (resultant vector), which ranged from 4.5 to 8.5 cm/s for the dynamic facial expressions, was greatest for the eyes closed tight expression. The mean maximum acceleration (resultant vector), which ranged from 193 to 465 cm/s/s, was greatest for the eyebrow lift expression. Symmetrical time plots were obtained. The system documented synkinesis by revealing substantial left upper eyelid motion during the nose-wrinkle expression in an illustrative case with slight left facial dysfunction. CONCLUSION: This approach to facial motion analysis is feasible for the simultaneous, multiregional, spatial-temporal assessment of facial expressions. Because motion at relatively remote regions could be quantified, this approach is potentially useful for the evaluation of synkinesis.

Adult↗
PubMed2000

An assessment of the validity of a computer system for probabilistic record linkage of birth and infant death records in Canada. The Fetal and Infant Health Study Group.

Studies on the validity of probabilistic record linkage are sparse. We performed a probabilistic linkage to link the 1984-1994 birth records (obtained from the Canadian Birth Data Base) with 1984-1995 infant death records (from the Canadian Mortality Data Base) in Canada. We extracted the linked birth-death records for Nova Scotia and Alberta (from January 1990 to December 1991) obtained from Statistics Canada's vital registration data and compared them with corresponding records from provincial data (primarily hospital records). The results showed that over 99% of infant deaths (153/155) in the Nova Scotia provincial data were successfully located in the linked Statistics Canada file; the corresponding figure for Alberta neonatal deaths was also 99% (365/367). The distributions of gestational age and birth weight in matched cases demonstrated high agreement between the two data sources. We conclude that the computer system for probabilistic linkage developed by Statistics Canada using the available personal identifying variables in the Canadian Birth Data Base and the Canadian Mortality Data Base is valid.

Alberta↗
PubMed1985

Versatile high-performance liquid chromatographic computer system for solvent delivery, gradient control and data acquisition using the Commodore 64 personal computer.

An interface for a high-performance liquid chromatographic system based on the Commodore 64 personal computer has been designed as an alternative to the expensive and somewhat inflexible solvent programmers and data acquisition systems offered by commercial manufacturers. The system consists of the Commodore 64 with a single disk drive and monitor, and an interface that directly controls the flow-rates of two Waters pumps for solvent delivery in either isocratic or gradient mode, as well as analog-to-digital conversion of chromatographic data and either graphic data output to a dot-matrix printer or digital-to-analog conversion for output to a chart recorder. The interface permits computer-controlled flow-rates of up to 10.0 ml/min, with an accuracy of 0.0047 ml/min at flow-rates of 4.1 ml/min and an accuracy of 0.03 ml/min at flow-rates of 10 ml/min. The software for data analysis permits tabulation of elution times and areas for the peaks in a chromatogram with an option for baseline correction. The data are stored on floppy disks together with information pertinent to the chromatogram (flow-rate, solvent composition, etc.).

Chromatography, High Pressure Liquid↗
PubMed1990

On the development of an integrated computer system for cephalometric analyses.

This paper describes a microcomputer based system that integrates image processing and computer graphics techniques to automate the data extraction and storage process in cephalometric analyses. The system increases the consistency of measurements and improves the productivity of surgical and dental staff.

Cephalometry↗
PubMed1995

Neural network control of functional neuromuscular stimulation systems: computer simulation studies.

A neural network control system has been designed for the control of cyclic movements in Functional Neuromuscular Stimulation (FNS) systems. The design directly addresses three major problems in FNS control systems: customization of control system parameters for a particular individual, adaptation during operation to account for changes in the musculoskeletal system, and attaining resistance to mechanical disturbances. The control system was implemented by a two-stage neural network that utilizes a combination of adaptive feedforward and feedback control techniques. A new learning algorithm was developed to provide rapid customization and adaptation. The control system was evaluated in a series of studies on a computer simulated musculoskeletal model. The model of electrically stimulated muscle used in the study included nonlinear recruitment, linear dynamics, and multiplicative nonlinear torque-angle and torque-velocity scaling factors. The skeletal model consisted of a one-segment planar system with passive constraints on joint movement. Results of the evaluation have demonstrated that the control system can provide automated customization of the feedforward controller parameters for a given musculoskeletal system. It can account for changes in the musculoskeletal system by adapting the feedforward controller parameters on-line and it can resist the effects of mechanical disturbances. These results suggest that this design may be suitable for the control of FNS systems and other dynamic systems.

Adaptation, Physiological↗
PubMed2006

Estimation of future outflows and infrastructure needed to recycle personal computer systems in California.

The objectives of the present study are to estimate future quantities of electronic waste (e-waste) for which appropriate infrastructure needs to be established, and to the estimate the total cost for e-waste recycling in California. Estimation of the future amounts of e-waste as a function of time is critical to effective e-waste management. To generate estimates, we use a time-series materials flow analysis model (MFAM). The model estimates future e-waste quantities by modeling the stages of production, usage, and disposal. We consider four scenarios for the estimation of future e-waste generation in order to consider the effects of exportation outside the State of California and of user preferences to store or to recycle the e-waste. These efforts were further investigated through the use of sensitivity analysis. The results of the present research indicate that the outflow (recycling) amount of central processing units (CPUs) will increase and will reach approximately 8.5 million units per year in 2013, but the outflow (recycling) of cathode ray tube (CRT) monitors will decrease from 2004 in California because of the replacement of CRT monitors by liquid crystal display (LCD) monitors. In 2013, the cost for CPU recycling will be 1.7 times higher than that in 2005. But for CRT monitors, the cost for recycling in 2013 will be negligible. After the State of California enacted the ban on landfill disposal of e-waste, recycling became the most common end-of-life (EOL) option in California. Also, after 2005, the State of California will need more than 60 average-capacity materials recovery facilities (MRFs), to recycle the number of personal computer systems generated, which represents an investment in capital of over 16 million dollars.

California↗
PubMed1978

Graduate education in computer systems in medicine--a conceptual model. Canadian Organization for Advancement of Computers in Health.

A conceptual model of the graduate educational programme in medical informatics is discussed. Problems involved in different types of informatics training can be avoided by stressing the integrative aspects of a systems approach. This programme is designed to lessen the gulf between a higher level of hardware capability and the ability to use it. The increasing educational demands in medical information systems have put more pressure on educational establishments to respond more expertly.

Biomedical Engineering↗
PubMed2001

Neural network in communication with medical computer system.

The paper presents a concept of an experimental module designed to recognize spoken utterances that cover a limited range of words indispensable in dialogs with computer medical systems. Research into the recognition of spoken words by a module based on artificial neural network is described. Usefulness of the obtained results for surgery-assisting multimedia systems and for a patient simulator supporting medical education of students in case history-taking and diagnosing is also discussed.

Computer Systems↗
PubMed2002

Facial motion analysis with a video and computer system after treatment of acoustic neuroma.

OBJECTIVE: To objectively evaluate facial function with a computer and video system in a group of normal adults and a group of adults who have been treated for acoustic neuroma. STUDY DESIGN: A prospective descriptive study was performed in which the experimenter performing the objective facial motion analysis was blinded to the subjective rating of facial function. PATIENTS: The normal subjects comprised 18 women and 16 men. The subjects who had been treated for acoustic neuroma included 12 patients (seven women and five men) who underwent treatment for acoustic neuroma. METHODS: Light-reflective markers were placed at selected facial sites. A video and computer-assisted system was used to measure displacement that was unconfounded by head motion at these sites during two expressions. Proximal and remote displacement were measured for the x and y coordinates. Percentage of asymmetry relative to the total displacement was determined. RESULTS: Significant asymmetry in displacement for the y coordinate during the eyes-closed expression occurred in 100% of the subjects who had been treated for acoustic neuroma with apparent facial dysfunction and 0% of the subjects who had been treated for acoustic neuroma with no apparent facial dysfunction. Synkinesis was severe (>0.2 cm) in 17%, moderate (0.1-0.2 cm) in 25%, mild (>95th percentile for normal subjects but <0.1 cm) in 42%, and absent in 16% of the subjects who had been treated for acoustic neuroma. CONCLUSION: This method of objective assessment of facial function is useful in the evaluation of the asymmetry in facial motion and in the detection and quantification of synkinesis. The findings suggest that those subjective rating systems of facial function that compare the abnormal to the normal side may be confounded by compensatory motion on the presumed normal side.

Adult↗