Digital Laboratories Research Articles

P3314 Corrected TIMI frame count (cTFC): applicability in modern digital catheter laboratories when angiograms are acquired at different frame rates

P3314 Corrected TIMI frame count (cTFC): applicability in modern digital catheter laboratories when angiograms are acquired at different frame rates

Digital echocardiography.

Continued improvement in the computer price-to-performance ratio and the adoption of international standards have enhanced the feasibility of completely digital echocardiographic laboratories that were initially described more than a decade ago. Digital archival has distinct advantages over analog recording, including improved laboratory efficiency, capability of side-by-side comparison of current and historical studies, streamlined image storage, and enhanced interinstitution image transfer. Studies have demonstrated that clinical and electronic image compression allows efficient storage of data, without affecting diagnostic accuracy. Finally, digital echocardiography has important telemedicine applications.

The Kodak approach to digital cardiovascular imaging laboratories.

Cine film had been a global standard in the cardiac catheterization lab for the acquisition, archive, review and exchange for decades. The advent of digital imaging in the cath lab heightened the desire to store cath procedure images in a digital format. The issues related to the development of a digital exchange standard, the data capacities and data rates, lossless and lossy compression, and techniques to obtain digital image data from the lab are discussed. In addition, Kodak's approach to cine film replacement with digital systems is described.

Reproducibility of quantitative coronary analysis, Assessment of variability due to frame selection, different observers, and different cinefilmless laboratories.

Because of limited storage capacity for digital images, angiographic laboratories without cinefilm are dependent on locally performed quantitative coronary angiography (QCA) in clinical studies. In the present study the intra- and interobserver variability, as well as variability between different laboratories and variability due to frame selection was analyzed. A total of 20 coronary lesions were studied in two different laboratories 12 +/- 8 days apart. Images were analyzed on-line and after being transferred to a Cardiac Work Station (CWS). There was no significant difference between the measurement situations. For minimal luminal diameter (MLD) precision (SD of signed errors) ranged from 0.12 mm to 0.20 mm, for reference diameter (RD) from 0.15 mm to 0.28 mm, and for percent diameter stenosis (DS) from 4.2% to 5.8%. Overall relative precision was obtained by normalizing the QCA parameters, as well 11.9% for MLD, 7.0% for RD and 8.5% for DS (p < 0.001, Rd and DS compared to MLD). The overall variability in the interobserver and in the interlaboratory comparisons was 11.2% and 10.4%, respectively (n.s) (n.s.). Thus the variability of QCA performed in cinefilmless, digital laboratories is small, and within a range making it an useful tool for clinical practice and group comparisons in clinical studies. However, the error range of QCA measurements must be taken into consideration when judging results from individual patients.

Building Data Storage Systems And Data Networks To Support Digital Microscopy

Abstract As laboratories like the Materials Analysis User Center (MAUC) in the High Temperature Materials Laboratory, at Oak Ridge National Laboratory move from analog to digital imaging systems, the process for acquiring, processing, analyzing, and publishing research results is changing. In this case since original scientific data exist only in digital form, analog systems for gathering, staring, and transmitting data are being set aside in favor of digital systems. In order to adequately protect original scientific data and to ensure that digital laboratories have the same (or greater) functionality as analog laboratories, scientists must focus on building information systems that make data highly available, highly reliable, and quickly accessible. Meeting these three objectives imposes special requirements for both data storage systems and data networks.

Building data storage systems and data networks to support digital microscopy

As laboratories like the Materials Analysis User Center (MAUC) in the HTML at ORNL move from analog to digital imaging systems, the process for acquiring, processing, analyzing, and publishing research results is changing. In this case since original scientific data exist only in digital form, analog systems for gathering, storing, and transmitting data are being set aside in favor of digital systems. In order to adequately protect original scientific data and to ensure that digital laboratories have the same (or greater) functionality as analog laboratories, scientists must focus on building information systems that make data highly available, highly reliable, and quickly accessible. Meeting these three objectives imposes special requirements for both data storage systems and data networks. A data storage system for a digital microscopy laboratory must have a very large capacity (at MAUC, 30 GB). In addition, the data stored within the system must be highly available and highly reliable.

A programmable logic array suitable for use in digital system design laboratories

A specially designed programmable logic array (PLA) suitable for use in digital system design laboratories for undergraduates is presented. Rewriting the PLA is done just by transferring the new codes; no explicit erasing process is required. The number of product terms allowed implementation on the PLA is unlimited. The computation speed of the PLA is less than 100 ns. The PLA can communicate with a host computer by accepting a variety of commands for writing PLA codes and monitoring input and output values for the PLA. Using software tools developed for the PLA, the student can perform laboratory experiments at various levels. Another software tool permits programming the PLA in a high-level language. The excitation (next-state) and output functions of a controller circuit are naturally described in a simple syntactic construct. Laboratory experiments utilizing the PLA and student responses are also given. >

Programming support for IC design in ULA technology

A programming tool for IC design in ULA technology is described. It is shown that it gives a great support by significantly decreasing the time to develop IC elements and by increasing the reliability of the product. Basic procedures of the system, namely grouping, placement and routing are detailed. Its important features lie in possibilities for backtracking and interactive handling of the system. As it is written for IBM-PC compatible users, its wide usage by researchers in digital laboratories and by other PC users is expected.

A 16-Bit Microcomputer for Audio Bandwidth Digital Filtering

Small microcomputers using 8-bit machines have been used in teaching digital filtering and discrete-time control. These systems have two major limitations: 1) bandwidth limited to approximately 125 Hz for fourth-order algorithms, and 2) limited precision for representing the coefficients in the algorithm. This paper describes the development and application of a high-speed 16-bit machine which largely overcomes the limitations of previous systems. A special-purpose digital filtering and control computer was built using the MC68000 microprocessor operating at 12.5 MHz. This machine uses 16-bit data transfers to memory and 32-bit arithmetic. The multiply and divide instructions are microcoded in the instruction set, and therefore execute much faster than subroutines used in 8-bit machines. The system has a general-purpose monitor routine and a digital filtering algorithm in firmware, user RAM, two channels of A/D, two channels of D/A, a programmable timer, and an RS232 interface for a CRT. The firmware implements any filtering or compensation algorithm through eighth order in the form of a linear difference equation. The greater precision of the 16-bit machine allows the coefficients in the difference equation to be represented accurately without extensive rationalization procedures. The firmware is written for student use in digital filtering and control laboratories. The computer prompts the user for coefficients and the sampling interval, informing him of any input errors. It then continuously runs the selected algorithm until interrupted. This system has been found to be of much wider bandwidth than previous machines. Signals of 4.

Microprocessor-based IEEE-488 interfacing unit as a development aid

The IEEE-488 standard has become one of the major standards for instrument interfacing used today, finding wide application in automatic test equipment and microcomputer-based controllers. This article describes a microprocessor-based IEEE-488 interfacing unit that is now in use as a development aid in our digital control laboratories. The unit offers an answer to specialized signal generation and intelligent data acquisition.

Labs for digital systems

Digital systems laboratories are to the set up at five universities and one polytechnic, under the Science and Engineering Research Council's scheme for providing more expertise in digital computing and microelectronic systems. This represents the first stage of the SERC's initiative in the field, and it is expected to cost about £1m.

Digital hardware design and test method

This paper discusses a project carried out at the Digital Laboratories of the Twente University of Technology. The purpose of the project was twofold: Firstly, to develop a digital hardware design and test method. Secondly, to build a hardware interpreter for an intermediate code of Pascal, the so-called P4 code. The implemented P4 machine is based on AM2901 bit slices. During the project a P4 interpreter running on an Intel 8080 system, and a microprogram assembler for the AM2901 were developed. This paper focuses on the hardware design and test method as applied to the implementation of the P4 machine. In particular, the simulation and emulation aspects of the method are discussed.

Microprocessors in undergraduate digital design laboratories

The decreasing costs of digital processors coupled with the dramatic increase in their actual and contemplated use in systems design and product engineering make it imperative that electrical engineering students understand the characteristics and capabilities of digital processors as system components. Educating undergraduates to understand the structure and behavior of digital processors as components presents a different set of problems from those encountered in teaching engineers computer programming. This paper outlines the requirements for such education, concluding that the use of LSI microprocessors in the digital laboratory offers the best solution. The choice of laboratory topics to be covered and the selection of equipment are discussed, along with some possible classes of experiments. The relationship between these laboratory courses and the selection of equipment are discussed, along with some possible classes of experiments. The relationship between these laboratory courses and other topics in the EE curriculum is treated briefly. Finally, an appendix is included which lists and briefly discusses the phased acquisition of equipment and implementation of the undergraduate EE digital systems laboratory at the authors' institution.

A course in minicomputer systems

The study of minicomputer systems in a laboratory environment has been considered by both Electrical Engineering [1], and Computer Science [2] departments. In a summary of the COSINE Committee report on Digital Laboratories, Booth [1] points out that since minicomputers are becoming an integral part of many industrial systems, it is mandatory that students be made aware of the principles of such systems. Further, Booth suggests that the best way to accomplish this is in a projects-oriented laboratory environment. We certainly agree with his statement that “A successfully completed project thus gives the student a sense of accomplishment that is hard to duplicate in any other educational situation.”

Design of an Audio Logic Tester

The design of a simple logic tester producing audio outputs is described. These audio outputs are distinct frequencies, approximately an octave apart, and correspond to the logic states '0,' '1,' and 'fault,' as defined for transistor-transistor logic (TTL) integrated circuits. The tester can be easily modified to detect pulses or logic levels of other types of circuits. It is expected that such a testing circuit will provide a useful aid in undergraduate digital laboratories.

An Economical Self-Supervised Individually Operated Open Electronics Laboratory

A senior electronics laboratory at Michigan Technological University has operated for more than a year with 100 students each term working individually on an open laboratory basis. The objectives of the laboratory are to teach the theory and practice of experimentation and supplement engineering theory presented in the classroom. Students schedule their laboratory time in two-hour blocks and perform experiments alone without direct supervision. This laboratory has increased development of experimental skills for all students compared with traditional group operation. The laboratory has functioned on a small budget with no new equipment in the first year and no increase in instructor time. This mode of operation is presently being extended to selected analog, digital, and electromagnetic laboratories.

Undergraduate digital laboratories

Digital circuits are rapidly replacing analog circuits in many areas of electrical engineering. The undergraduate curriculum in electrical engineering has reflected these changes by including more course work in the digital area. The availability of low cost integrated circuit logic elements and minicomputers has made it possible to provide a digital system laboratory program that allows the student to undertake the design of realistic digital systems. This paper discusses the organization of such a laboratory program and the facilities needed to carry out this program.