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A new feature of optical free induction decay (FID) is observed in a coherently prepared sample of $^{13}\mathrm{CH}$$_{3}\mathrm{F}$ by the method of Stark switching. The preparative phase is due to the resonant steady-state excitation by a cw laser beam, and is followed by FID upon sudden application of a dc Stark field that switches the molecular sample out of resonance. The emission is not observed as a simple decay but instead appears as a train of sharp pulses regularly spaced in time as a result of a repetitive interference. This situation arises because an entire set of infrared transitions within the Stark split manifold are initially prepared, in contrast to our previous study of a nondegenerate transition. The emission, which beats with the laser, produces a heterodyne beat spectrum, consisting of a set of regularly spaced frequencies, that is the Fourier transform of the slowly decaying pulse progression observed. We thus demonstrate what is the optical analog of the well-known NMR method of high-resolution pulse Fourier spectroscopy. The detailed behavior of the pulse train agrees well with an FID theory that assumes the transitions to be uncoupled. The subtle behavior of FID near the time origin is explored also by approximate analytic expressions that reveal either a near zero amplitude or sizable amplitude depending on the degree of saturation in the preparative stage. The experimental technique discussed offers an attractive way for obtaining high-resolution optical spectra without Doppler broadening, and for generating an optical pulse train whose time scale can be compressed by simply increasing the Stark field.

A method is described which allows chemical shifts in solids to be detected to a good accuracy by sharply determining the first moment. The analysis is made by using spin-temperature concepts and it is shown that the chemical-shift tensor can be determined if a single tensor contributes to the spectrum, and the average if more than one tensor contributes. Measurements are made in a single crystal of KH 2 PO 4 . The average tensors obtained are axially symmetric about the c axis with σ // =-25.6 ppm and σ ⊥ =-8.3 ppm relative to C 6 H 12 for 1 H(300 K), and with σ // =-1.1 ppm and σ ⊥ =-16.5 ppm relative to 85% H 3 PO 4 for 31 P(77 K). These values are discussed qualitatively. The 19 F chemical shift in CaF 2 is also obtained, and the result is in good agreement with that of pulse train method.

We derive the spectral density of a sinusoidal carrier phase modulated by a random baseband pulse train in which the signaling pulse duration is finite and the signaling pulses may have different shapes. The spectral density is expressed as a compact Hermitian form in which the Hermitian matrix is a function of only the symbol probability distribution, and the associated column vector is a function of only the signal pulse shapes. If the baseband pulse duration is longer than one signaling interval, we assume that the symbols transmitted during different time slots are statistically independent. The applicability of the method to compute the spectral density is illustrated by examples for binary, quaternary, octonary, and 16-ary PSK systems with different pulse overlap. Similar methods yield the spectral density of the output of a nonlinear device whose input is a random baseband pulse train with overlapping pulses.

By using the model of two level atoms and the boson description of the Frenkel excitons, the dispersion relation of the polariton for intense radiation field is investigated. It is shown that the quenching effect of the dipole moment and the effect of the exciton-exciton interaction modify the dispersion curve significantly. The possibility of the self-induced transparency of a pulse wave is examined by taking into account the polariton effect, and a negative answer is obtained.

The echlocation signals of two Atlantic bottlenose dolphins, Tursiops truncatus, were measured while the animals were involved in a target‐detection experiment conducted in open waters. The time intervals between successive pulses in a pulse train were found to be highly variable, although the intervals were longer than the time needed for an acoustic signal to travel from the animals to the target and back. Sound pressure levels of the echoranging signals were measured for target ranges of 60, 70, 75, and 80 yds. The peak‐to‐peak click‐source level at 1 yd showed little variation with the target range; the average level was 120.4 dB re 1 μbar for one animal and 122.3 dB for the other. These open‐water sound pressure levels are at least 30 dB higher than any click‐source levels reported in the literature. Oscilloscope photographs and their Fourier transforms of these high‐amplitude clicks are presented. The typical clicks had average durations of 40 μsec, with peak energies between 120 and 130 kHz, much higher than the previously reported energy peaks centered at 35 to 60 kHz.

Arterial pulse wave velocities, pulse wave contours, and systolic time intervals were recorded in thirty-nine diabetic children and were compared with recordings taken in twenty-seven normal children. Systolic time intervals were similar in the two groups of subjects. However, brachial and aortic pulse wave velocities were significantly greater in the diabetic than in the normal children (p

To obtain wider waveform equalization range and higher synchronization accuracy, we have introduced: 1) a multilevel pilot-pulse equalization system and 2)an in-band in-phase pilot synchronization system into multilevel VSB-conversion PCM-FDM equipment. This equipment is used to transmit digital signals on existing analog lines. 1) Multilevel pilot pulses with a smaller number of levels than the information pulses are inserted into the information pulse train. Due to the larger eye opening of the received pilot pulse, the automatic equalizer can converge and equalize the distortion more quickly and easily. For example, let 2-level pilot pulses be inserted into every 32 16-level information pulses. As long as the eye pattern of the pilot pulse is open, it is possible to allow up to 15 times more distortion in the transmission line. Thus the transmission span can be greatly extended. There are various other advantages in using this pilot pulse, such as dc drift suppression, in-service error rate monitoring, etc. 2) A carrier pilot and a sample timing pilot for phase synchronization are superimposed on the carrier frequency and 1/2 Nyquist rate, respectively, within the transmission signal spectra. Thus no excess bandwidth for pilots is necessary, and the phase error between pilot and signal is smaller. In this case, the phase jitter of regenerated carrier and timing clock caused by the neighboring signal spectra can decrease if the pilots are coupled in the same phase with the neighboring signal. For example, phase jitter of less than 0.5° (which was experimentally 1/10 phase error of the quadrature coupling) could be realized easily, even if the signal-to-pilot ratio is about 20 dB.

The onset of the picosecond pulse train in a passively Q-switched and modelocked solid state laser occurs with a considerable time jitter. A method has been devised which employs double-pulse pumping of the laser rod as a means to substantially reduce this jitter. With the ruby laser used, a reduction of more than twenty times, from 35 μsec to 1.5 μsec, was observed without altering the characteristics of the mode-locked pulse train or flash-lamp life. The synchronization of auxiliary equipment is thus made possible.

The set of coupled Maxwell-Schroedinger equations that govern the propagation of ultrashort pulses through a nonlinear laser medium are solved analytically in the steady-state regime. The periodic energy exchange, between the intense passing electromagnetic field and the stationary aggregate of two-level atoms, leads to doubly periodic jacobian elliptic-function solutions. Their modulus k is a function of the characteristic time length of the system τ and the pulse amplitude ξo. The physical properties of these steady-state solutions are considered. It is shown that there are in essence only four periodic pulse-train solutions sdu, ndu, and dn, where u is the retarded time t - z/v referred to the characteristic time τ. τ and the period of the pulse train T are controlled by the steady population-inversion density ηo, which is established by external means. Two of these solutions expand with intensified optical pumping while the other two contract under the same conditions.

A system for identifying moving objects such as vehicles, trucks, buses, containers, etc., in which a passive label having a number of dipoles in accordance with a code is attached to the object, is described. A synthetic aperture radar consisting of a Gunn diode mounted within a resonant cavity and connected to a horn is used to illuminate the label. The Gunn diode operates as a homodyne so that signals from the label are also detected by the diode as a number of overlapping chirp signals, which are sent to a computer for processing. The computer output is a pulse train with pulses corresponding to dipoles in the label. A number of tests have been made indicating that labels can be read regardless of range and vehicle speed. A number of horns may be strategically located in a city or along a highway, and these horns can be multiplexed into a common computer to provide an inexpensive all weather automatic vehicle identification system.

A myoelectric signal, under isometric contraction of the muscle, is modelled as the output of a linear time-invariant system whose input is a stationary Poisson pulse train. The mean frequency γ of the Poisson pulse train and the transfer function of the linear system are evaluated using the spectral properties of the signal. An estimate of the number of active motor unitsN contributing to the myoelectric signal is obtained under the assumption that the individual motor-unit trains are statistically independent. The variation of γ andN with respect to load levels and electrode positions is examined experimentally.

Summary The effect of a simple model of a geological fault on an incident plane SH wave pulse is considered by using the approximate technique recently developed by the author for seismic wave problems involving lateral discontinuities. Calculated pulse forms are presented for the reflected, transmitted and diffracted wave fields. The technique used is shown to be successful in representing the diffraction effects of thin faults and should therefore provide a useful aid to the understanding of the interaction of seismic waves with truncated structures. When a propagating wave meets a ‘corner’ such as is formed by the sudden termination of a horizontal layer or by the tip of a buried wedge, diffraction will take place. The importance of such diffractions, and their association with geological faults, has been recognized for many years in seismic prospecting but relatively little theoretical work has been done on the nature of seismic diffraction. Skuridin (1955) has investigated the effect of a rigid step fault on a plane P wave using the form of representation theorem introduced by Kupradze (1950), but this work was confined to harmonic time dependence. The problem of the diffraction of an elastic wave pulse by a half-plane diffractor has been considered by Maue (1953) and extensively by de Hoop (1958), but they have given no visual presentation of their results. The remaining work which has been done on diffraction effects for seismic wave pulses has been confined to the acoustic wave approximation. Krey (1952) used Sommerfeld’s results for the diffraction of an acoustic wave by a half-plane to present diffracted wave forms for a crude model of a fault. Trorey (1 970) has derived approximate solutions to the acoustic wave equation subject to certain boundary conditions, to derive pulse forms for diffraction from discontinuous horizons characterized by reflection coefficients, any transmission effects being ignored. In this paper we consider the effect of a very simple horizontally discontinuous structure on an incident plane SH wave pulse. The model we consider approximates a truncated horizontal layer or a layer containing a plane of discontinuity inclined to the vertical. We use the method for handling such problems which was recently introduced by the author (Kennett 1973a-subsequently denoted as Paper I) to look at the character of both the reflected and transmitted waves and the corresponding diffractions. This fairly simple approximation is shown to provide quite a good description of the seismic wave field.

Further investigation of a problem originally considered by the author (Chester 1950 a ) is carried out. One of the results of the above-mentioned paper is a description of the disturbance produced inside a two-dimensional, open-ended channel when a transient sound wave approaches the open end. At large distances from the open end this disturbance may be regarded as a plane wave travelling into the channel, and expressions were obtained for the potential and velocity distributions in a limited region at the head of the wave. The present paper discusses the asymptotic behaviour of the disturbance at large distances from the wave front. It is found that, for an incident Heaviside unit pulse, the wave inside the channel also tends to behave like a unit pulse, the correction term being O (1/ s ) where s is the distance from the wave front. The asymptotic behaviour for an arbitrary incident pulse is also considered and illustrated with typical examples. The results are used to estimate the proportion of energy which returns along the channel when the incident pulse is of finite duration.

The clutter performance of coherent pulse trains is examined when the duration of the pulse train is increased to values for which range acceleration effects must be taken into account. The problem of target detection against a clutter background with differential Doppler is studied in terms of the range acceleration effects on the conventional Doppler response. Specifically considered are the consequences on the sidelobe level and width of the main Doppler lobe. The analysis shows that the sidelobe level remains essentially unchanged when the range acceleration mismatch becomes significant. However, the main Doppler response broadens in proportion to the magnitude of the acceleration mismatch. Thus, an increase of the signal duration for better Doppler resolution is useful only until acceleration effects spread the Doppler spectrum of the clutter and eliminate the differential Doppler between targets and clutter.

The propagation velocity of the pulse wave was examined in respect to age on the healthy children by obtaining the propagation time of the pulse wave of Saigusa et al at the finger-tip and calculating the velocity from this value and the length of the blood vessel.

The coherent pulse train has good clutter suppression performance because the energy in its matched-filter response is essentially concentrated within sharp ambiguous spikes. However, this is so only when the Doppler distortions are neglected, so that the Doppler effect is taken as a simple translation of the carrier frequency. This paper analyzes the consequences of Doppler distortions on the resolution performance of pulse trains. It is found that Doppler distortions widen the Doppler ambiguities of the pulse train response, with the widening factor proportional to the order of the Doppler ambiguity. This reduces the interval between Doppler ambiguities, and hence the Doppler width of a clutter space that can be accommodated without severe clutter interference. For an operation in a Doppler-ambiguous mode, it also degrades nominal Doppler resolution performance. A detailed analysis of the effects is presented, and numerical results on the widening of the Doppler ambiguities are obtained.

Designed for use on unloaded exchange cable, this repeater was developed to satisfy the transmission requirements of an experimental PCM system. It utilizes a pulse repetition frequency of 1.544 mc, and 6000-ft repeater spacing. Functionally, the repeatered line transmits the PCM signal without appreciable degradation over distances up to 25 miles, a feat accomplished by retiming and reshaping the signal at each repeater point. Retiming is accomplished by means of a clock extracted from the signal; reshaping is accomplished by regeneration with positive pulse width control. Near-end crosstalk and pulse train jitter dominate the design parameters. Timing is made tolerant of near-end crosstalk by choice of bipolar transmission (where successive marks are of opposite polarity) with clock derived from the rectified and clipped signal. Tolerance in the decision circuit is obtained by automatic threshold control, spike sampling, and tight control of time and voltage parameters. Accumulated pulse train jitter is controlled to the extent dictated by the terminal equipment, principally through control of the bandwidth of the clock circuit. Seven diffused-base transistors and ten logic diodes are used in the oneway repeater circuit. A two-way repeater consists of two such circuits with a common power unit, utilizes 135 components, and is packaged in a can of $1{1 \over 16} x 3{1 \over 8} x 5{3\over 4}$ -inches outside dimensions. Accommodations are made for line-length and power options, as well as remote testing. Power for the repeater is transmitted over the signal pair. One watt is required for the two-way repeater.

The CAVORT analog radar signal processor for matched filtering of coherent pulse trains from targets displaying significant radial acceleration is described. CAVORT employs a scanning technique to search repeatedly through trial pairs of values for Doppler and Doppler rate. When a target appears, it is detected, and the best-fitting pair of values determined. The principle of operation is illustrated, using photographs of waveforms generated by the equipment. The resuilts of satellite observations are included. It is demonstrated that the experimental CAVORT which integrates half-second segments of signal gives satisfactory estimates of acceleration.

In this section, experiments were performed in normal subjects in order to study whether several items of plethysmographic examination are useful or not for test a peripheral biood circulation, and gain control data in the normal subject.1. There were spontaneous variations in an amplitude as well as a base line of the plethysmogram at rest. In a grade of the spontaneous variations daily and individual differences were recognized.2. A crest time, a basic oscillation time, an amplitude of initial wave and its half decay time were measured on each wave of the plethysmogram. Since individual differences in the crest time and the half decay time were little, a comparison of these two element with a pathological wave form are regarded to be significant.3. A propagation time of pulse wave was represented by a time from the Q wave of electrocardiogram to a rising point of the plethysmogram. It was 0.244sec (0.219-0.272sec) for the third finger and 0.313sec (0.301-0.324sec) for the big toe.4. When an extremity under test was shifted passively from a heart level, there were specific patterns in variations of a base line and an amplitude of the plethysmogram for each position (elevated or lowered) 5. Whcn a hand clap or a mental arithmetic were applied to the subject, a base line of the plethysmogram moved to a direction of vasoconstriction.From these results, following items were selected as standard items of the plethysmographic examination. (1) Spontaneous variations in an amplitude and a base line of the plethysmogram. (2) A wave form of the plethysmogram. (3) A propagation time of pulse wave. (4) Changes in a base line and an amplitude of the plethysmogram when an extremity under test was raised or lowered from a heart position. (5) Vasomotor reflex.

This paper presents a new and simple technique for evaluating the correlation function and the power spectrum of a randomly shaped pulse train defined as y(t) = ??hn(t-tn) n--? where the {hn(·)} are random functions that describe the shape of the pulses and where the random occurrence times {tn} constitute a stationary point process. The obtained results are very simple, and various illustrations are given.

Members of the Santa Barbara basketball team were tested periodically during and after the 1957–58 season of play. The changes in physical conditioning were estimated using a step test. During this period of time the blood pressure and pulse wave measurements were studied to investigate the effects of basketball conditioning on these measurements. The resting and postexercise systolic blood pressure measurements decreased significantly during training. These changes were significant after 16 weeks, while the pulse rate changes indicated conditioning had changed in six weeks. During de-training these measurements reversed and made significant changes in ten weeks. The pulse wave measurements more closely followed those of the step test. They changed significantly in six weeks, leveled off, and finally reversed to the starting level during de-training.

The purpose of the simulator is to serve as a substitute for human subjects while developing and testing equipment measuring PWV continuously over long periods of time. For this purpose the shape of the simulated pulse should have the geometrical properties of the arterial pulse wave essential for measuring foot to foot PWV. These properties were defined and realized by choosing an appropriate input function and a shaping network. It was proved, by calculations based on steady state analysis, using Laplace transforms, that the simulated arterial pulse wave has the defined geometrical properties. The dicrotic complex, which sometimes interferes with foot to foot PWV measurements, was added to the simulated pulse wave by a separate circuit.

To understand the patterns of nerve impulses produced by sinusoidal stimuli, a simple model is considered which integrates input currents with a finite time constant until a threshold voltage is reached, whereupon an output pulse is produced and the process is restarted. We show here that (a) a general analytic solution exists for this model driven by sinusoidal stimuli, determining the interval between every member of the pulse train, (b) for all values of the parameters of the model a pattern exists which repeats periodically after a finite number of pulses in the absence of noise, (c) the system will approach a stable pattern which, if perturbed, will be recovered once the perturbation is removed, (d) the linear integrator or relaxation oscillator and the curren multiplier are limiting cases of this model.

T1 carrier provides 24 voice channels by time division multiplexing and pulse code modulation (PCM). Each voice channel is sampled 8000 times a second and each sample is coded into a 7-digit binary word. Provision for signaling and synchronization raises the pulse repetition rate on the repeatered line to 1.544 × 106 pulse positions per second. The bipolar pulse train out of the terminals is transmitted over pulp, paper or plastic insulated paired cables by the use of regenerative repeaters. For 22-gauge cable pairs, repeaters are normally located at 6000-foot intervals. The system has been designed for low cost and is being widely applied on many trunks interconnecting switching units within metropolitan areas. Western Electric Company manufacture of T1 began in 1962 and about 100,000 channels are now in service throughout the Bell System.

Direct measurements with a picosecond streak-camera show that 1 mJ pulses, of transform limited durations ( Δt ∼ 3 psec, ΔtΔν ∼ 0.5), are produced at the beginning of the pulse train of a mode-locked Nd: glass laser. Pulse durations increase to ∼ 10 psec at the end of the train, with self-phase modulation frequency broadening. The optimum length of the contacted saturable absorber cell was found to be ∼ 50 μm , in agreement with earlier work using two-photon fluorescence measurements.

Observers were required to detect double jumps of a diffuse light spot jumping in a circular pattern and more intense noise pulses in a pulse train. Seven groups performed at different combinations of stimulus and signal frequencies, higher signal frequency/stimulus frequency ratios, and lower stimulus frequencies. Stimulus frequency was a more potent determiner of performance than signal frequency, and performance was not invariant within a given signal frequency/stimulus frequency ratio. Correlations of dependent measures were also examined.-Results are discussed with reference to various theories of vigilance behavior.

A device is described which (1) generates very accurate time calibration tones suitable for tape recording along with experimental behaviors, and (2) creates from such a recorded tone an easy-to-read structured pulse train for oscillographic tracings. Calibration tones at 1-, 5-, and 10-kHz pulse rates are derived from a crystal oscillator module and are made available for tape recording at one output of the device. The second output produces a four-level structured pulse train in which there is one pulse for each cycle of the calibration tone (every 10th is a little larger, every 100th a little larger yet, and every 1,000th larger still). An example of the use of this device in speech, timing research is given.

A pulse train generator capable of giving trains of fast pulses is described. The instrument, that may be used in testing electronic circuits to be used in high energy nuclear physics experiments, gives an output formed by trains of pulses of both polarity 10 V amplitude and 3.5 ns rise time, whose time separation may be changed between 60 ns and 300 ns. The diagram of the circuit is reported, together with long term and temperature tests.

Sequential constraints, in the form represented by equal frequencies within blocks, were imposed upon finite-state statistical generators. The sequences were encoded in the form of interval-coded pulse trains and were transduced to sound by earphones. In discrimination tests, interval thresholds between the finite states provided a measure of the relative discriminability between different sequential constraints. These thresholds are shown to be quantitatively related to the difference in uncertainty in specification of the sequences. To a first approximation: Equal interstate interval thresholds are associated with equal differences in uncertainty.

It is now well established that in cases of aortic regurgitation placed in the horizontal position the arterial pressure is considerably higher (50-80 mm. Hg) in the leg than in the arm. Such pressures are taken by the sphygmomanometer, using the armlet method, the armlet being placed respectively round the calf and the upper arm, the disappearance and reappearance of the pulse wave being noted in the dorsalis pedis or posterior tibial artery, and in the radial. In seeking for an explanation of this phenomenon it has already been suggested by us that the “lability” of the arterial wall plays a considerable part, the term “lability” being used to designate the ease with which an artery distends with a rise and recoils with a fall of arterial pressure. The effect of increased and of diminished lability of the vessel wall upon the conduction of the pulse wave has been demonstrated schematically by Russell Wells* on rubber tubing made with a thickness of wall corre­sponding to an artery. While the lability effect has been shown by us in exposed arteries, in the body the main arteries are surrounded with tissues permeated with small arteries into which the blood pulsates. As the arterial wall is supported by the pulsing tissues the lability effects obtained on the exposed arteries cannot be directly ascribed to the same arteries in situ . Further investigation must be made on these.

A quasilinear partial differential equation of the second order has been obtained to describe the flow of a viscous fluid through tubes with elastic walls. The equation has been generally derived from the variational principle. Applying this method to the description of the blood flow in arteries, an expression describing the velocity of the propagation of the pulse wave has been given. Passing over to the linear theory one obtains results consistent with those of Korteweg and King.

Insect-eating bats find their aerial food by sonar, through emitting ultrasonic chirps and locating sources of echoes. Certain moths have ears sensitive to these chirps and can detect bats well beyond the range of the bats' sonar. On hearing a distant bat, many moths turn and fly directly away from the source of ultrasound. Only one sense cell in each ear of a moth provides the primary nervous information for this response. This article describes my initial attempts to find out how a moth's central nervous system processes the train of chirps reaching its two ears. The ear of a restrained moth is exposed to a sequence of artifically generated ultrasonic pulses that approximates the cries made by a bat. This stimulus can be varied with respect to ultrasonic frequency (pitch), pulse intensity, pulse duration, the interval between pulses, and pulse-train duration. The more sensitive acoustic sense cell responds to all frequencies between about 15,000 and 80,000 cycles per second, but the signal that it transmits to the moth's central nervous system contains no measure of frequency within this range. However, this nerve signal reports variations in the other parameters of the stimulus. The acoustic fiber connects, in the central nervous system, with various nerve cells that transform the signal farther. The signal from a pulse-marker neuron contains no measures of pulse intensity or pulse duration, reporting only changes in interpulse interval and pulse-train duration. A train-marker neuron reports only the duration of the pulse train. The stimulus parameters may be likened to keys, each of which is necessary to gain admittance through a given door but becomes superfluous once this door has been passed. This analogy suggests one of the ways in which a signal is transformed in its passage through the nervous system, and how its specificity is assured in eliciting a given response. In addition to undergoing this kind of transformation, neural signals generated in the two directionally sensitive ears must be combined if a flying moth is to steer a course away from a distant bat. Neurons have been discovered in the central ganglia which summate signals from the right and left ears. Other neurons are inhibited in their activity by stimulation of one ear. The moth may combine signals from these neurons with motor-nerve information on the attitude of its own wings, which act as oscillating baffles modifying its directional acoustic sensitivity 20 to 40 times a second as it flaps an erratic path through the darkness.

The present study was performed in order to spot the patient having the Raynaud's phenomenon by inducing iontophoresis while the Raynaud's phenomenon is latent. Ten subjects were divided into two groups each of which was composed of five, one group of patients having the Raynaud's phenomenon and the other serving as the control. As the pain was felt when a current 2 mA or more was introduced and when the current was rapidly increased, a current of 0.5 mA at the beginning and 1.9 mA at the end, increasing by 0.1 mA in every two minutes, was applied. The method of iontophoresis was as follows. At first, a solution of 0.1% noradrenalin was introduced by the above procedure, and next, a solution of 0.5% histamin was perfused by the same procedure. Plethysmogram after noradrenalin iontophoresis was round-shaped and its amplitude (mean) corresponded to 4.3 μl in the patient group. On the contrary, plethysmogram of the control group was sharp and its amplitude (mean) corresponded to 7.4 μl. Namely, a reduction of pulse wave amplitude had occured after the noradrenalin iontophoresis in the patient group. When histamin iontophoresis was operated subsequently, pulse wave amplitude of the control group increased above the amplitude of the patient group. The pulse wave amplitude at the time of histamin iontophoresis was compared with that before histamin iontophoresis, and it was observed that the increment of the pulse wave amplitude of the patient group was larger than that of the control group. However, this tendency was not found in a few persons among the patient group. This might be related with the functional abnormality in individuals among the patient group.

In an investigation now being carried out by us at Manchester observations are being made, under various conditions, upon the velocity of the pulse wave in man. As a preliminary to this investigation it was thought advisable to study the theory of the transmission of the pulse wave, and the following pages contain the results arrived at, together with an account of experiments upon the velocity of the pulse wave in an isolated human artery.

(1949). Diagnosis of Arteriostenosis (Arterial Occlusion) With the Aid of Pulse Wave Recordings. Scandinavian Journal of Clinical and Laboratory Investigation: Vol. 1, No. 3, pp. 177-186.

The microvibration or minor tremor (MT) on the body surface of man and rabbit was recorded under various physiological conditions. The electrocardiogram (EKG) or heart beat and sometimes electroencephalogram (EEG) were also traced simultaneously with the recording of MT to elucidate the physiological significance of the mechanism of the development of MT. In some cases, correlation and frequency analyses were performed on MT to obtain their average time-and frequency-patterns.In MT tracings under the relaxed condition, two groups of vibrations corresponding to the first and second heart beats or the R and T waves of EKG were observed. This synchronization was more evident in the crosscorrelogram of the heart beat or EKG and the MT than in the original MT tracing. In the autocorrelograms of MT, a damping of oscillation with a beat phenomenon was clearly shown.In the power spectra of the autocorrelograms, several peaks were recognized in the so-called alpha frequency which confirm the beat oscillation in the autocorrelograms.However, its frequency range was often broader than that of the alpha wave in EEG.Even when the radial pulse was suppressed by pressure on the upper arm, the two groups of main vibrations appeared which corresponded to the R and T waves of EKG.This finding suggests that these vibrations are not closely related with the pulse wave and/or other vibrations of the artery caused by the blood flow, but rather related to vibration of the body surface due to the heart beat.During sleep and in the awake state, in which the inhibition and acceleration of MT were observed respectively, the same correspondence between MT and EKG as that in the relaxed was also demonstrated.It was suggested from the above results that the regulating system of the heart beat in addition to so-called muscle tonus might also play an important role in the inhibition and acceleration of MT under various physiological conditions.A part of this (or rabbit) research reported in this document has been made possible through the support and sponsorship (DA-92-557-FEC-35764) of the U. S. Department of Army, through its Far East Research Office. The authors thank sincerely to Dr. Z. KIYASU, K. IBUKI and T. KIMURA for applying the computer MI-B.

Coherent optical signal processing techniques can be used to perform pattern identification test procedures. It is shown that there are four properties of the optical signal processing techniques that are necessary and sufficient for pattern identification. The purpose of this paper is to present a candidate neural pattern identification procedure and a realistic neuron network model able to execute the pattern identification procedure.The identification procedure and neuron network model are obtained from an analogy between coherent optical systems and neuron networks. The four neural analogs of these optical properties are identified and shown to be reasonable neural properties. The four analogs between optical and neural systems compare and identify: (1) the neuron's pulse rate with the magnitude of a light wave, (2) the ‘phase difference’ between any two synapses with the phase difference between any two points in the coherent light beam, (3) the spatial dispersion of the neuron's pulse train with the...

Figures 1 to 3 represent a condensed account of some wave pulse experiments carried out in a long tank equipped with a wavemaker. The object of the experiments was to observe the effects of finite amplitude on the shape and frequency distribution of wave pulses propagated on deep water. Each pulse was generated by varying the wavemaker stroke smoothly from an amplitude of zero to some maximum value and back down to zero again. The resulting surface displacement was then recorded electrically at various positions along the centreline of the wave tank. The wavemaker frequency was 2·5 c/s throughout (corresponding to a regular wavelength of about 10in.). The pulse periods, which were selected to represent rapid and slow rates of modulation, were 12½ and 25 wavemaker periods.

The need for data on the perception of sounds produced by the excitation of resonance systems is discussed in relation to speech and psycho-acoustics. The voltage response of a series of N decoupled low-pass resonator sections to the sudden application of various types of input pulse trains is reviewed. The output of such a series of resonators to a recurrent impulse which is suddenly applied contains a d.c. term, a series of transient terms at the uncoupled resonator frequencies, and a steady-state term involving the harmonics of the input pulse train. A circuit for psychophysical tests is described which provides a number of discrete positions of resonator frequency and damping. Sound spectrographic analyses demonstrating the transient and steady-state terms for a single resonator are presented.

Finger pulse wave was recorded in 144 womens consisting of 100 key-punchers, 24 normal control and 20 patients with scalenus syndrome, by means of a pneumatic strain gauge transducer plethysmograph. The contour of pulse wave was classified in six groups, vis. catacrotic, peak flat, anacrotic, sclerotic rigid, vasospastic and plateau. Geometrical analysis of the pulse wave was carried out, eight indices being adopted. Percentages of the normal pattern of the pulse wave, comprised of catacrotic plus peak flat wave, were ca. 85% in the normal control group, ca. 35% in patients with scalenus syndrome, and ca. 45% in key-punchers. Whereas, those of vasospastic wave plus plateau wave, which is said to represent the spasm of peripheral vessels, were ca. 35% in key-punchers, 6% in the control group and 20% in patients with scalenus syndrome. In the finger pulse wave of key-punchers, a statistically significant decrease of elasticity index, a significant increase of dicrotic index, relatively descending time at the half-way of the peak amplitude, and that of relative amplitude at the half-way of the diastolic phase, and the reduction of peripheral blood flow were observed. The finger pulse wave of key-punchers with complaints represented neurovascular symptoms such as pain, numbness, hyperaesthesia and coldness of the hands, arms and shoulders or the neck, showed only the prolongation of relative ascending time at the halfway of the peak amplitude compared with that of the key-punchers without complaints. Both geometrical analysis and wave form of the finger pulse wave of key-punchers revealed no significant difference in the arms with and without complaints. The finger pulse wave of punchers engazed in key-punching over 10 years indicated a tendency to increase in peripheral vascular resistance, such as the increase in the dicrotic index and the relative descending time at half-way of the peak amplitude, the decrease of the elasticity index and the shorting of the propagation time compared with the group of key-punchers whose length of service are less than 10 years. When the modified Adson's maneuver (elevation of the chin, looking toward right and left side alternatively) was employed in subjects, no significant change was found in geometrical analysis of the finger pulse wave of both the key-punchers and of the control. In the scalenus syndrome group, however, the increase of the relative descending time at half-way of the diastolic phase was observed when the patients rotated his neck to the left side as well as a significant reduction of peripheral blood flow when rotated to the right or the left side. When key-punchers, whose pulse wave classified as vasospastic and plateau type, lay on their back with arms raised so high as 90 degrees in the angle for 30 seconds in the duration, contours of the finger pulse changed from vasospastic or plateau wave to the normal wave (catacrotic or peak flat). Therefore, peripheral hemodynamics of the key-punchers was manifested as vasoconstrictive and its cause would not likely be organic but rather functional. The vasconstriction of the finger, estimated from the finger pulse wave, was more prominent in the group of key-punchers engaged in key-punching more than 10 years and this appeared to be independent of their complaints.

We derive upper and lower bounds on the probability of error of M -ary CPSK systems subject to intersymbol interference and additive Gaussian noise. The bounds are expressed in terms of the error probability obtained with a finite pulse train and some parameters associated with the residual pulse train. Methods are given to compute the probability of error with a finite number of interference terms and it is shown that the difference between the upper and the lower bounds is a monotone decreasing function of the number of pulses in the finite pulse train. The applicability of the method to compute the probability of error with any desired degree of accuracy is illustrated by examples for quaternary and octonary systems.

Records of the first derivative of the brachial pulse have been secured in over 175 subjects, 68 of whom were healthy persons, and the rest of whom were ambulatory hospital patients. Such records emphasize certain features of the conventional pulse, such as angles, notches, and slurs, and suppress other features, such as the slow movements of the base line. From data secured in the healthy subjects, normal standards have been defined for contour, for amplitude of the chief deflection, and for the durations of the main waves on the base line. As age advances, the main wave of the pulse derivative diminishes in amplitude and becomes broader on the base line, even though health commensurate with one's age is retained. Conspicuous abnormalities of the contour of the pulse derivative were identified by inspection in 43 hospital patients, in all of whom conventional hospital studies gave strong evidence of cardiac abnormality. Four persons who believed themselves to be healthy showed similar abnormalities of the pulse derivative contour. The amplitude of the main wave of the pulse derivative indicates the maximum rate at which blood pressure rises on the advancing pulse wave front. Amplitudes greater than normal were found in 25 patients. No one was encountered who had an amplitude less than normal; the reason for this is discussed. Abnormalities of wave duration were identified in a small number of patients—the exact number depended on whether this duration was expressed as time or as per cent of the cardiac cycle. Changes in the amplitude and duration of the main wave of the pulse derivative permit one to identify aspects of the cardiac performance which change as age advances. These indicate the “normal” weakening of the myocardium as one grows older. Abnormalities of contour of the pulse derivative indicate an incoordination of the cardiac contraction.

An electronic instrument which generates a train of constant amplitude pulses occurring at random times is described. The average pulse rate of this process is a linear function of a controlling voltage. The intervals between successive pulses form a renewal process and the probability density of these intervals may be varied from an exponential distribution to a gamma distribution of variable form. Statistical measurements on the pulse train are described which support the claims on its statistical properties.

A hydrodynamic model of the systemic circulatory system was mounted on an ultralow-frequency ballistocardiograph (ULF-BCG). The relationship between stroke volume and ballistocardiographic amplitude was investigated for different pulse wave velocities. It was found that the amplitude of the displacement ballistocardiogram, as used by Klensch (“J”M minus “I”J), is strongly correlated to stroke volume; however, the relationship is highly dependent on pulse wave velocity. Closer evaluation of the data showed that there is a combination of amplitude measurements that also gives a strong correlation between amplitude and stroke volume but is now independent of pulse wave velocity.

The binary rate multiplier is a device which has been used for many years in hybrid computing (operational digital techniques) and control systems as a means for generating a pulse train of average frequency proportional to the value of a binary number stored in a register. In general, the pulse spacing is irregular and the number of pulses generated in a given time fluctuates above and below the number which would be produced by a perfectly regular pulse train at the same average frequency. These fluctuations constitute a short-term frequency error, the value of which is an important parameter in the design of pulse rate digital systems incorporating binary rate multipliers. This article analyzes the conditions under which maximum positive and negative errors occur, and expressions are derived from which the magnitude of such errors may be calculated.