Apple IIe Research Articles

Analysis of Pipe Networks by the Finite Element Method

ABSTRACT In this paper, the finite element technique used in the analysis and design of water distribution networks will be presented. The method was applied successfully to the solution of three different networks. In order to demonstrate the feasibility of the approach and to show some merits and demerits of the finite element method, a comparison was made on a digital computer with the standard Hardy Cross method. In all cases the finite element method was shown to provide superior performance. Moreover, the programmes were run on three different machines [Wang vs 100, Apple IIe, and IBM micro-computer] to show the effect of increasing storage capacity, machine accuracy, and time saving.

7243. Witness plate electron beam diagnostic for electron cyclotron maser research: S N Spartk and A D R Phelps,Meas Sci Technol, 1, 1990, 352–355

A project to determine some long-term statistical properties of the terrestrial meteor flux is described. A passive, 55 MHz (US -TV channel 2), forward-scatter radiometeor detection and simple (Apple IIe) computer logging system is used to record the epoch, duration and peak power of all echoes with durations greater than 0.09 s and less than 2 min. The system has been in continuous routine operation from March 1993 to March 1998 with occasional interruptions due to sporadic E, troposcatter and equipment outages. Over 2,000,000 events have been recorded and logging is continuing on a 24-h basis. Grouping by echo type is done statistically at the data processing stage. Using only a small fraction of the available data, we show that this system produces valid and useful scientific results in spite of the fact that meteor velocities are not obtained. Through computer-aided statistical analysis, some of the milestones achieved are: (a) automatic separation of events into overdense, transition and underdense categories, and compilation of various statistics on these groups or some combination of them; (b) confirmation of a diurnal effect on average underdense trail durations; (c) confirmation of an apparent ozone depletion effect on the durations of overdense meteors; (d) interpretation of an apparent peak-power and duration correlation for overdense echoes in terms of the Manning forward scattering model and (e) confirmation (through a power spectrum analysis of hourly rates) of the presence of sporadic radiant sources of approximately 20° of half-intensity-halfwidth which exhibit a 20–30% 16 day variability.

Color modulation of Doppler spectra with the use of a personal computer

This paper describes a method for the use of a personal computer in developing color modulated spectral maps of blood flow echoes from a Doppler flowmeter. The acoustical signal from a Doppler flowmeter is digitized and transformed into the frequency domain with a fast Fourier technique with the use of an Apple IIe microcomputer in conjunction with a Motorola 68000 co-processor. The resultant transform is displayed as a pseudo three-dimensional, color modulated spectral map by way of a color monitor, or a television projector onto the meeting room screen. We have found this technique to be useful in appreciating differences in blood flow from different hydraulic conditions, as well as in helping the medical students appreciate these differences in pulsatile flow in various arteries.

Vibrational relaxation in SiF4 using a computer-controlled ultrasonic interferometer

A variable-path ultrasonic interferometer has been modified to permit automatic data collection and analysis utilizing an Apple IIe microcomputer and an ADC interface board possessing a crystal-controlled clock for precision data sampling. The micrometer screw is driven by a synchronous motor also controlled by the interface board. The system allows rapid sampling and recording of the crystal driving voltage for each resonant node in the gas column, thereby reducing running time and improving overall accuracy and sensitivity. For SiF4, the (single) vibrational relaxation time was found to be (2.20±0.14)×10−8 s at a temperature of 304 K and 1 atm of pressure.

Effects of body position and bolus consistency on the manometric parameters and coordination of the upper esophageal sphincter and pharynx

The development of a solid-state intraluminal sphincter transducer has alleviated many of the problems associated with manometric studies of the upper esophageal sphincter (UES) and pharynx (P). We used this technology to study the effect of position (upright vs. supine) on resting UES pressures and the pressure dynamics of the UES/P complex during both wet and dry swallows in 11 normal volunteers and the effects of foods of different consistencies on the UES/P swallow dynamics in 10 normal volunteers. The UES/P coordination parameters were defined as the 15 time intervals that can be measured between any 2 of 6 pertinent points: the beginning, peak, and end of the pharyngeal contraction and the beginning, nadir, and end of the UES relaxation. Data from both the circumferential transducer used to measure sphincter pressures and a standard microtransducer used to measure pharyngeal pressures were collected on-line by an Apple IIe microcomputer and analyzed by programs written in our laboratory. Significant changes in swallow coordination were measured between upright and supine swallows of the same bolus size, between wet and dry swallows in the same position, and among foods of varying consistencies. Resting UES pressure was unchanged by position and pharyngeal contraction pressure was unchanged by bolus size or consistency.

An automated microcomputer-controlled system for neutron activation and gamma-ray spectroscopy

An automated instrumental neutron activation analysis (INAA) system has been constructed at the SLOWPOKE-2 reactor at the Royal Military College of Canada (RMC). Its pneumatic transfer system is controlled by an Apple IIe computer, linked in turn to an MS-DOS-compatible microcomputer which controls data acquisition. Custom software has been created for these computers and for off-line spectral analysis using programs that incorporate either peak boundary or Gaussian peak fitting methods of analysis. This system provides the gamut of INAA techniques for the analyst. The design and performance of the hardware and software are discussed.

Computer analysis of the exploratory behavior of insects and mites in an olfactometer

A method of quantification of the exploratory behavior of small animals stimulated by an odorant in a four-choice olfactometer, taking into account the interindividual variability of responses, was developed: individual tracks were time sampled according to the animal's walking speed and its positions were recorded according to the X-Y coordinates of the grid set underneath the device, the mesh of the grid suiting the animal's body size. A software, written in BASIC APPLESOFT on an APPLE IIe computer, allowed us to analyze the coordinates either of a single individual or of an experimental sample, leading to: a) the quantification of the insect distribution all over the experimental chamber, expressed in a table numbered according to the grid, where the percentages of position per square either for a given time fraction or the total observation period were reported, b) a graphic representation of the data according to several levels of greys, expressing the frequentation for each square for a given duration of observation. An analysis per time fraction allowed the chronological setup of events to appreciate. c) The collection of the positions among each flow field of the olfactometer for each individual of the experimental sample, for a given duration, was translated as the percentage of time spent in each flow field. Data files gathered these percentages for further statistical treatments. This computer method, which requires little equipment and appears to be easily adaptable to the study of biological models of various size and speed such as honeybees, trichogrammas and varroas mites, is a powerful tool for behavioral studies of small organisms tested in restricted areas.

Sensitive digital lock-in amplifier using a personal computer

The low-frequency sensitivity limitation provided by internal 1/f amplifier noise is eliminated by employing lock-in detection. Since low frequency noise spectral analysis commonly uses digital processing and fast Fourier transform techniques, it is convenient to use digital lock-in detection as well. A simple digital lock-in amplifier based on an Apple IIe personal computer is capable of detecting signals many orders of magnitude below the internal l/f noise of a PAR (Princeton Applied Research) 113 amplifier.

A Computerized Curd Firmness Meter

The curd firmness meter was interfaced with an Apple IIe computer to increase both the efficiency of the instrument and the accuracy of the instrumental measurements. The computerization allows for collection of real-time data, graphical analysis, and maintenance of results in a data base capable of generating reports. The newly modified curd firmness meter can measure the firmness of cheeses and gels. The mean, lowest, and highest firmness points are obtained from the computer-generated, force-time curve. The mean firmness values distinguish among samples, and the low and high firmness points give information on variability within samples.

Classroom demonstration—Generating an ROC curve from the energy detection of signals in random noise

Students enrolled in “Underwater Acoustics and Sonar” at the Naval Academy benefit from a “hands‐on” demonstration of binary detection theory. The relationships between the respective probabilities of detection, miss, false alarm, and null [P(D), P(MISS), P(FA), P(NULL)] are examined for different thresholds. Two loudspeakers, driven respectively by random noise and a pure tone, simulate the acoustical environment. The output of a microphone is sent through an analog multiplier and a low‐pass filter, which act as the detector. An Apple IIe computer with a digital oscilloscope card displays the output and performs the probability density function on the processed signal. PDFs of (a) noise alone and (b) noise plus a signal are used to generate the receiver operating characteristic (ROC) curve. [Work supported by the Naval Academy Research Council.]

An Investigation of Somatic Anxiety and Intelligence in Children Using the Kaufman-ABC and an Apple IIe Program Measuring Heart Rate

Somatic anxiety during intelligence testing was examined for 43 children in Grades K through 5 by assessing each child's heart rate with an Apple IIe computer program during an administration of the Kaufman-ABC. Heart rate (a measure of somatic anxiety) decreased steadily during the course of the test administration, except for an increase when the one timed subtest (Triangles) was administered. Heart rate during each separate subtest did not correlate significantly with performance on any task. Implications of these preliminary findings are discussed.

Pharyngeal and upper esophageal sphincter manometry in humans

Manometric studies of pharyngeal-upper esophageal sphincter (UES) coordination during swallowing have proven difficult. Asymmetry of the UES makes pressure measurements with a single, unoriented transducer suspect. Perfused systems lack the necessary response rate for measuring peak pharyngeal contraction pressures. Precise quantification of the coordination of pharyngeal contractions and UES relaxations during swallowing is difficult because of rapid pressure changes. We tested a modified solid-state transducer that measures pressures over 360 degrees. This transducer was placed in the proximal UES with a second, single transducer 5 cm proximal. Data were collected and analyzed with an Apple IIe microcomputer. A computer program was developed to measure nine timing sequences, UES resting pressure, nadir of UES relaxation, and pharyngeal contraction pressures. We studied 21 volunteers with six swallows each for dry, 5, 10, and 20 ml of water. Dry swallows differed significantly (P less than 0.05) from wet (5 ml). All timing sequences became progressively longer with increasing bolus size. Residual pressures were unchanged. Timing sequences were also measured for wet (5 ml) and dry swallows in seven volunteers using a Dent sleeve and single perfused orifice in the UES; no differences were seen.

Intonation and Fundamental Frequency in Male-to-Female Transsexuals

Twenty speakers, diagnosed as male-to-female transsexuals, produced conversational recordings of speech and voice. The samples were submitted to perceptual evaluations and to acoustic analysis by means of a Visi-Pitch, Apple IIe microcomputer system. Transsexuals categorized as having female voices had higher fundamental frequencies (fo), less extensive downward intonations, a higher percentage of upward intonations and downward shifts, and a smaller percentage of level intonations and level shifts than transsexuals categorized as having male voices. The lowest average fo identified as belonging to a female speaker was 155 Hz. Higher (more feminine) ratings on the masculinity-femininity dimension correlated with fo (r = .89), percentage of level shifts (r = -.67), percentage of downward shifts (r = .50), percentage of level intonations (r = -.43), and percentage of upward intonations (r = .40). Findings are discussed in terms of the relative perceptual salience of average fundamental frequency and patterns of intonation for female voice quality.

Development of 3-dimensional molecular descriptors

Abstract Structural invariants used currently as molecular descriptors in structure-property (SPR) and structure-activity relationship (SAR) studies are based on molecular graphs rather than on a structure as a 3-dimensional (3-D) object. Here we outline an approach which extends graph-theoretical methodology to structures embedded in 3-D space. Derived descriptors are sensitive to the 3-D characteristics of a molecular structure and change with variations in molecular conformations. We illustrate the approach by examining conformations of smaller alkanes, including selected conformations of cyclohexane, methyl-cyclohexanes and cyclooctane. In particular, we report the atomic path numbers and atomic ID numbers (i.e. local descriptors), and molecular path numbers and molecular ID numbers (i.e. global descriptors). The path numbers were weighted so that a path of length 1 corresponds to the molecular connectivity index χ. This paper should correct the widely held misconception that graph-theoretical analysis is not applicable to 3-D molecular structures, and at the same time should alert those interested in SPR and SAR to the availability of 3-D structural invariants of potential use in QSPR and QSAR models. The examples given and the computational background suffice to inform a potential user to write her/his own software, or to modify the existing ALL PATH program in order to obtain the novel 3-D molecular invariants. The computations were performed on an Apple IIe personal computer (with a program written in BASIC).

Microcomputers in an Introductory College Astronomy Laboratory: A Software Development Project

We have developed software for the Apple IIe series of microcomputers for use in labs in an introductory astronomy course. This software emphasizes a toolkit approach to data analysis; it has been class tested with over 170 students and was a resounding success as a replacement for previously used graphical approximations. A unique feature of this software is the incorporation of image-processing techniques into a course designed for non-science majors.The five software packages are:(a)Datasheet - A six-column spreadsheet with columnwise operations, statistical functions, and double-high-resolution graphics.(b)Image-Processor Program - Allows 37 × 27 pixel × 8 bit video captured images to be manipulated using standard image-processing techniques such as low pass/high pass filtering and histogram equalization.(c)Picture-Processor Program - Allows 256 × 192 bilevel pictures to be manipulated and measured with functions that include calipers, odometer, planimeter, and protractor.(d)Orrery Program - Simulates planet configurations along the ecliptic. A movable cursor allows selection of specific configurations. Since both relative times and angular positions are given, students can deduce the scale of the solar system using simple trigonometry.(e)Plot Program - Allows orbital positions as observed from above the pole to be plotted on the screen. By entering trial values of elliptical orbit parameters, students obtain and the program plots the best fitting ellipse to the data. The sum of the squares of the residuals in the radial coordinate is given after each trial so that students can discover convergence more easily than by simple visual examination of a plot comparing the trial theoretical points with the raw data points.

Effects of a task-specific warm-up on anaerobic power.

Twenty-four untrained (UT) males (age 21 +/- 2.5 yr, height 1.77 +/- 0.05 m, weight 75.3 +/- 10.1 kg, values mean +/- SD) performed the Wingate Anaerobic Test (WT) under two conditions, cold (C) and following a warm-up (WU). Trials were separated by a minimum of 48 h. A modified Monark 818 cycle ergometer was interfaced with an Apple IIE microcomputer and peak power (PEAK), mean power (MEAN) and fatigue index (FI) determined. The WU trial consisted of an 8 min incremental continuous cycling bout (cadence 90 rev.min-1) with 5 min rest before the WT. During the C trial subjects completed only the WT. A repeated measures design was employed with order of trials counterbalanced. ANOVA revealed no significant differences for PEAK or MEAN between WU or C conditions. However FI was significantly greater (p less than 0.05) following the WU. A significant correlation (r = 0.45, p = 0.03) was obtained between WU intensity and FI. These findings suggest that our UT subjects were fatiguing themselves during the WU. Future studies are needed to assess whether a task-specific WU in which FI is not impaired would lead to improvements in PEAK and MEAN. Investigators should be aware that a self-spaced WU may increase FI in the WT in UT subjects.

Technique of on-line analysis of diaphragmatic electromyogram activity in the newborn

The present study provides an on-line analysis of diaphragmatic electromyographic activity (EMGdi) in newborns. EMGdi was recorded using surface electrodes. EMGdi signals were processed using a microcomputer (Apple IIe). The centroid frequency (Fc) and the high over low (H/L) frequencies ratio of the power spectrum were calculated. Furthermore the model frequency (Fo) was computed by an autoregressive model of the EMG signal. EMGdi analysis was performed in seven healthy spontaneously breathing preterm newborns. Fc ranged from 46-62 Hz. Fc was significantly lower than Fo in four of the seven preterm newborns. The coefficient of variation for Fc was significantly lower than for the H/L ratio (p less than 0.001). The coefficients of variation for Fo and Fc were not significantly different, but the percentage of rejected calculations for Fo was significantly higher than for Fc (p less than 0.01). Therefore, in healthy preterm newborns, Fc appears to be the best index of EMGdi analysis.

Utilisation d'un générateur de système expert pour la conduite de procédé en chimie au laboratoire de développment

Research carried out to date on the automated versatile modular reactor set-up, in the development laboratory, has shown the complexity of security In the present work, an expert system generator is used, Nexpert (software from Neuron Data), in order to create an expert system able to manage the mo The control system consists of a Macintosh computer. Interaction between the control system and the process is achieved by means of an Apple IIe comput

The Rate of Vascularization of Coralline Hydroxyapatite

Coralline hydroxyapatite (CHAP) is a porous, biocompatible bone-graft substitute manufactured by the Replamineform process. The use of this material in the experimental and clinical settings for maxillofacial onlay grafting has been recently described. This study was designed to quantitate the rate of vascularization of coralline hydroxyapatite when used in an onlay application to membranous bone in an animal model. Sixteen onlay grafts of coralline hydroxyapatite (0.5 X 0.5 X 1.0 cm Interpore 200) were placed in a subperiosteal location on the nasal dorsum of 2- to 3-kg male New Zealand white rabbits. The grafts and nasal bones were harvested en bloc at 1, 2, 3 and 4 weeks after onlay. Prior to harvest, injectable silicone visualizing agent (Microfil*) was injected by means of carotid artery cutdown. The decalcified specimens were examined on a digitizing pad to count the number of vessels appearing in the blocks of hydroxyapatite. Counting was summed and integrated by an Apple IIe microcomputer. A significant difference (p less than 0.05) was noted in both the number of vessels and the fraction of implants infiltrated by vessels between 1 and 4 weeks. The usefulness of these previously undescribed data may be in their extrapolation to onlay grafts of coralline hydroxyapatite in maxillofacial reconstruction in humans.

Screen display and timing synchronization on the Apple IIe and Apple Ilgs

The logic of the vertical blanking interval (VBL) Softswitch in the Apple Ilgs is the reverse of the logic of the VBL in the Apple IIe. Programs written for the Apple IIe that synchronize the videoscan with the experiment control program timing by sensing the VBL pulse will therefore function incorrectly when run on an Apple Ilgs. Procedures for modifying existing synchronization routines are discussed. A flexible alternative program that senses the type of computer on which it is running and accordingly adjusts the logic of the synchronization routine is described.