Desktop Personal Computer Research Articles

Radiotherapy patient scheduling using a desktop personal computer

This paper describes the transition from a conventional paper based patient scheduling system for radiotherapy to a computer based system in a busy clinical department. The hardware and software requirements are set out, together with a description of the current advantages and future potential for development of the system as part of a mathematical model of departmental activity.

On the erosion of heat exchanger tube banks in fluidized-bed combustors

Erosion (usually referred to as metal wastage) of heat exchanger tube banks in bubbling atmospheric and pressurized fluidized beds is a serious issue that may affect their reliability and economics. A simplified version of the comprehensive monolayer energy dissipation (MED) erosion model, developed by us earlier, is presented. This study illustrates the application and usefulness of this simplified MED erosion model to quickly and easily produce trends and dependencies upon independent parameters. This version can easily fit on a pocket calculator or desktop personal computer. Predicted trends of erosion rate dependency upon the particle diameter, the fluidizing velocity and bed porosity using this model are discussed. Main fluidization variables are introduced in this erosion model by interpreting the solids—fluid interphase drag as the principal means of potential erosion. This simplified MED erosion model is compared with three other erosion models: the more comprehensive MED erosion model, the Finnie impaction erosion model, and the combined ductile—brittle Neilson—Gilchrist (N-G) erosion model. The simplified MED erosion model is shown to agree reasonably well with the maximum erosion data obtained experimentally at the Grimethorpe cold model facility of the Coal Research Establishment. A two-dimensional fluidized-bed geometry embodying three immersed tubes, which represents a generic approximation of the Coal Research Establishment cold models, is used to compare erosion model predictions. Detailed hydrodynamic calculations for this bed geometry were performed using the FLUFIX computer code and were used as inputs to the four erosion models. The comprehensive MED, the Finnie and the N-G erosion models predict an order-of-magnitude agreement with each other and with limited erosion experimental data. Good agreement is obtained between the relative trends predicted by the simplified and comprehensive versions of the MED erosion model.

Supercomputers in seismic data processing

Today's computers span a wide range of computing capability from desktop personal computers, through minicomputers and mainframes to the fastest, most powerful machines designed to the limit of existing electronics engineering technology. It is the last category, those that perform millions of floating point operations per second (megaflops) at the peak of current technology that are termed supercomputers. In seismic data processing extremely large volumes of numbers are processed through many stages, most of which involve complex mathematical operations. A typical seismic survey today is acquired with 300 recording channels to 6 s at a 2 ms sample rate. This recording configuration means that one kilometre of data produces 36 million samples (floating point numbers) for processing. Many seismic surveys today involve the recording of up to 10,000 kilometres of data, particularly 3D surveys. Processing techniques currently performed have evolved over past decades in accordance with the available electronic hardware of the time. The latest supercomputing technology allows more complex processing algorithms to be tested on data in realistic time, as well as the increased throughput capacity needed to accommodate today's large multichannel 2D and 3D seismic surveys.

1 The technical aspects of computers

This chapter is concerned with the technical aspects of computers. It is therefore concerned with how computers came about in the way they did, and who were the people who pioneered their development--what they were like in the early years, what they are like now, and what are likely to be the future developments. The emphasis is always on giving information to the readers so that they may know what questions to ask of the experts and, equally important, which experts to spend time with. In consequence of this last statement it becomes necessary to present a panorama showing the range of computers both size-wise and cost-wise; such scenario will therefore cover the vista from large main-frames (which must inevitably be needed in District Health Authorities and District General Hospitals) to the desk-top personal computers which all clinicians of the future will find essential. Because readers will be experiencing the impact and, hopefully, the benefits of the computer at the lower end of the size and price scale, considerable space has been devoted to explaining the various items (disc drives, monitors, printers) that pervade the microcomputer scene. New terminology must be introduced to readers if they are to discuss intelligently their computer needs to the providers of such facilities. Just as an automobile is no use without oil, petrol, water and a competent user, so the computer hardware needs computer software and a competent user. The chapter therefore continued with some considerable space being devoted to software (operating systems, programming languages, utilities and expert systems) so that the user will have clear guidance as to which path to follow in order to become a competent user of the present and future technology. Because of the rapid advances in data storage, in networking and in computer programs, the clinicians of tomorrow will have vast sources of information at their disposal. This latter will include not only patient records, but also drug data-sheets, textbooks, journals and research reports. Finally, lack of space has prevented some topics receiving more than a cursory mention. This is known but, like real life, one has to make judgements as to the relative importance of the topics and include those which come out top. It is hoped that the readers will not be too disappointed: if they absorb all that is here they will be very knowledgeable indeed.

Telecommunications opens new strategic vistas.

Telecommunications has become an essential part of every facet of today's business, yet many of us tend to take it for granted. Whenever we pick up the phone, fax documents or messages, or even transmit files from our desktop personal computers or laptops, we are putting telecommunications to use, but we hardly give it a second thought.

Blade-to-blade compressible flow analysis by the modified field singularity method.

Compressible flow analysis in turbine cascades was carried out by the use of the modified field singularity (sink/source) method that was originally developed by Van den Braembussche. This method has many noteworthy features : simplicity. compactness of program size and small memory size. all of which allow the program to run even on a desk-top personal computer. A comparison is made between experimental data or calculations of another numerical method (Denton method) and the results obtained with the proposed method in this paper. which shows its capability for subsonic blade-to-blade flow analysis.

Graphical output of health testing data

A new indicator to evaluate the health status of an examinee by computerizing selected health screening data has been devised and designated as a disease score. By employing such an index, it is possible to display to some extent the functional status of organs in simple, easily understood, computer-generated cartoons. Thus a computer program has been developed for a desk-top personal computer to calculate the disease score index from screening data and to generate an output in an easily understandable graphic and pictorial format. The disease score index with a graphic display (i.e., a disease map), a score graph and short comments are incorporated in the report form. This type of output should be especially useful in communicating with subjects who are screened and in helping them to understand selected aspects of their own state of health better. The index could also be helpful in screening and selecting subjects who require further detailed clinical examinations but this assumption needs full clinical evaluation to prove its efficacy.

Modular Control System Simulator

In this paper, we introduce a modular control system simulator for positioning servo applications. The program package was originally written for elevator car positioning simulations, but because of its straightforward modular structure it can easily be tailored for other types of applications as well. The simulator contains all the necessary functions needed to design an appropriate positioning servo when an estimate of the system model is known. The numerical system model is assumed to be a rational z-domain transfer function and it can be identified a priori from measured excitation and response signals by using some prediction error type algorithm. Although all the internal computations are performed using floating-point numbers, the simulator has built-in A/D and D/A converters to quantize the input and output sequences artificially. The simulator also has a programmable noise generator to generate additive measurement error to the simulated feed-back signal. The control and noise- filtering algorithms can be changed by replacing the existing modules with user-written FORTRAN subroutines. All the data transfers between individ ual modules are well defined to ensure easy modifiability of the overall system. The simulation software runs in a desk top personal computer.

The Business Benefits of PC Office Systems and End-user Computing at Glaxo Pharmaceuticals 1984-88

Since 1984, Glaxo Pharmaceuticals has seen a dramatic expansion in the use of desktop personal computers. The use of these machines for spreadsheet modelling and data analysis, databases, graphics, wordprocessing, project planning and statistical analysis, computer-based training and expert systems has transformed the nature of computing within the company and provided a platform for significant new co-processing developments. Over 1,300 personal computers have been installed in the company's four sites, providing a range of business benefits in terms of improved efficiency and effectiveness. Case studies of how these benefits have been provided are described, and a number of key issues for managing such change are discussed.

The Business Benefits of PC Office Systems and End-user Computing at Glaxo Pharmaceuticals 1984–88

Since 1984, Glaxo Pharmaceuticals has seen a dramatic expansion in the use of desktop personal computers. The use of these machines for spreadsheet modelling and data analysis, databases, graphics, wordprocessing, project planning and statistical analysis, computer-based training and expert systems has transformed the nature of computing within the company and provided a platform for significant new co-processing developments. Over 1,300 personal computers have been installed in the company's four sites, providing a range of business benefits in terms of improved efficiency and effectiveness. Case studies of how these benefits have been provided are described, and a number of key issues for managing such change are discussed.

Opening the Box of a Boxplot

Abstract Variations of the boxplot are suggested, in which the sides of the box are used to convey information about the density of the values in a batch. The ease of computation by hand of the original boxplot had to be sacrificed, as the variations are computer-intensive. Still, the plots were implemented on a desktop personal computer (Apple Macintosh), in a way designed to keep their ease of computation by computer. The result is a dynamic display of densities and summaries.

Calculation of coverage parameter : H. H. Amer and E. J. McCluskey. IEEE Trans. Reliab.R-36, 194 (1987)

The development of accurate, flexible and robust dynamic reduced order models (ROMs) is an important step towards greater commercialization of entrained flow gasifiers (EFGs). This two-part series of papers describes the development of such a ROM. Part I, below, describes the model, while Part II presents its validation for four EFG designs and sensitivity analysis. The ROM employs a reactor network model (RNM) that approximates fluid mixing and recirculation using a series of idealized chemical reactors; well-stirred reactors and 1-D plug flow reactors. The RNM is constructed such that the ROM is capable of simulating the operation of a range of commercial or research gasifiers and syngas cooler configurations. The ROM incorporates submodels for multiple feedstocks, mixing and recirculation, particle properties, drying and devolatilization, chemical kinetics, fluid dynamics, heat transfer, pollutant formation, slag behavior and syngas cooling. It is the first experimentally-validated gasifier simulator to incorporate all of the above submodels as well as possess dynamic capability. Modifications to some of the submodels from their original form to improve ROM accuracy, flexibility and robustness are also discussed. The ROM performs the steady-state simulations presented in Part II of this series in 1–5 min on a desktop personal computer, compared to multiple days on multiple processors for more detailed CFD-based simulations.

Experiments with microcomputer-based artificial intelligence environments

The U.S. Geological Survey (USGS) has been experimenting with the use of relatively inexpensive microcomputers as artificial intelligence (AI) development environments. Several AI languages are available that perform fairly well on desk-top personal computers, as are low-to-medium cost expert system packages. Although performance of these systems is respectable, their speed and capacity limitations are questionable for serious earth science applications foreseen by the USGS. The most capable artificial intelligence applications currently are concentrated on what is known as the “artificial intelligence computer,” and include Xerox D-series, Tektronix 4400 series, Symbolics 3600, VAX, LMI, and Texas Instruments Explorer. The artificial intelligence computer runs expert system shells and Lisp, Prolog, and Smalltalk programming languages. However, these AI environments are expensive. Recently, inexpensive 32-bit hardware has become available for the IBM/AT microcomputer. USGS has acquired and recently completed Beta-testing of the Gold Hill Systems 80386 Hummingboard, which runs Common Lisp on an IBM/AT microcomputer. Hummingboard appears to have the potential to overcome many of the speed/capacity limitations observed with AI-applications on standard personal computers. USGS is a Beta-test site for the Gold Hill Systems GoldWorks expert system. GoldWorks combines some high-end expert system shell capabilities in a medium-cost package. This shell is developed in Common Lisp, runs on the 80386 Hummingboard, and provides some expert system features formerly available only on AI-computers including frame and rule-based reasoning, on-line tutorial, multiple inheritance, and object-programming.

Practice in Online Flood Prediction by a Desk-top Personal Computer

Practice in Online Flood Prediction by a Desk-top Personal Computer

Magnetooptic erasable disk memory with two optical heads

A long lifetime and high-performance MO erasable disk memory is described. It has two optical heads for the erase and write operation. Previous information is erased by the erase head; subsequently, new information is recorded by the write head, which is equivalent to an overwrite operation for a magnetic memory. The recording medium is TbCo; this has a longer lifetime than other media, which contain Fe. All components are compactly formed into a standard 13.3-cm (5.25-in.) magnetic memory drive size. This disk memory will be used as a large capacity digital memory for desktop computers or personal computers.

A portable data-logging system for industrial hygiene personal chlorine monitoring.

The combination of suitable portable sensors or instruments with small microprocessor-based data-logger units has made it possible to obtain detailed monitoring data for many health and environmental applications. Following data acquisition in field use, the logged data may be transferred to a desk-top personal computer for complete flexibility in manipulation of data and formating of results. A system has been assembled from commercial components and demonstrated for chlorine personal monitoring applications. The system consists of personal chlorine sensors, a Metrosonics data-logger and reader unit, and an Apple II Plus personal computer. The computer software was developed to handle sensor calibration, data evaluation and reduction, report formating and long-term storage of raw data on a disk. This system makes it possible to generate time-concentration profiles, evaluate dose above a threshold, quantitate short-term excursions and summarize time-weighted average (TWA) results. Field data from plant trials demonstrated feasibility of use, ruggedness and reliability. No significant differences were found between the time-weighted average chlorine concentrations determined by the sensor/logger system and two other methods: the sulfamic acid bubbler reference method and the 3M Poroplastic diffusional dosimeter. The sensor/data-logger system, however, provided far more information than the other two methods in terms of peak excursions, TWAs and exposure doses. For industrial hygiene applications, the system allows better definition of employee exposures, particularly for chemicals with acute as well as chronic health effects.(ABSTRACT TRUNCATED AT 250 WORDS)

Using a pocket computer as a time study data collection tool

This paper discusses the use of a Radio Shack PC-2 pocket computer as a smart stopwatch. The PC-2 is a small (7.7″ by 3.4″ by 1.0″) low cost battery powered computer/calculator that is programmable in Basic. It also has an internal clock that is accessible to Basic, and an RS232 serial interface option that allows it to communicate with larger computers. A program is presented that turns the PC-2 into a smart time study stopwatch. A function key is used to record the start time of an activity. When it is pressed, the computer stores the start time in an array and prompts the user to enter an activity code. As the activity progresses other function keys may be pressed to change quantities or performance ratings, and add comments. Data from previous observations can also be examined and/or changed. Once an observation session is finished, the recorded data can be up-loaded to a desk top personal computer. The data can then be edited and recapped into a standard format. Note: The references in this paper to the Radio Shack PC-2 computer are not intended to be commercial. Several equivalent or close to equivalent machines are available from alternative vendors. The PC-2 is the machine that was purchased for the application presented.

Lap top computers review

Lap top computers are being heavily marketed by the manufacturers. They are useful for professionals on the move, but do not replace the desktop personal computers. In selecting a lap lop computer, portability, communications capabilities, size of memory, possible extensions and price should all be considered.

The Desktop Computer as a Network Participant

A desktop personal computer can be greatly extended in usefulness by attaching it to a local area network and implementing a full set of network protocols, just as one might provide for a mainframe computer. Such protocols are a set of tools that allow the desktop computer not just to access data elsewhere, but to participate in the computing milieu much more intensely. There are two challenges to this proposal. First, a personal computer may often be disconnected from the network, so it cannot track the network state and it must be able to discover and resynchronize with that state very quickly. Second, full protocol implementations have often been large and slow, two attributes that could be fatal in a small computer. This paper reports a network implementation for the IBM Personal Computer that uses several performance-oriented design techniques with wide applicability: an upcall/downcall organization that simplifies structure; implementation layers that do not always coincide with protocol specification layers; copy minimization; and tailoring of protocol implementations with knowledge of the application that will use them. The size and scale of the resulting package of programs, now in use in our laboratory for two years, is quite reasonable for a desktop computer and the techniques developed are applicable to a wider range of network protocol designs.

A desk-top personal computer for finite element post-processing

There is low cost, effective software for data processing available for use with desk-top personal computers. One such software package, called VisiCalc, is used on a TRS80 personal computer as a complement to some mainframe finite element post-processing. The TRS80 was attached to a time-sharing computer system to transfer some ADINA data to the TRS80's diskettes so that the data could then be reviewed with VisiCalc after disconnecting from the time-sharing system. VisiCalc post-processing was limited to review and graphical display of data that represented the contact pressure between a tire model and a road surface. However, the techniques and specialized programming can be easily extended to provide other types of data reduction and review. Also, the procedures are directly extendable to other desk-top personal computers.