The study was directed, first of all, toward the detailed analysis of the operation in business office. As far as the view of industrial engineering is concerned, it seems to be some problems to reduce clerical costs and to provide better management information.
We discuss the benefits and operating advantages that can be gained through the use of EDPS in business office. We also describes electronic data processing of admission and discharge procedure, particularly supplying information to prospective patients, room reassignment, and transfers the patients to other floor.

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In order to produce a handy and reliable instrument for the measurement of ultrasonic sound pressure in liquids, two of the authors have developed a series of calibrated probe microphones for the frequency ranges of 10 to 300 kc and 100 to 1000 kc. This paper describes the construction, method of calibration, sensitivity of the probe microphone and, as an example of its medical application, an experiment carried out by the other authors on the quantitative analysis of the acceleration effect of ultrasound on the osmosis through semipermeable membrane to be used in an artificial kidney. The probe micro-phone principally consists of a thin metal rod, ceramic transducing element and sound absorbing tail soldered in tandem. The sound pressure at any point in liquid medium is picked up by one end surface of the rod, and it propagates through the rod and ceramic element without any reflection until being absorbed in the tail. Such a reflectionless construction permits of a flat response over a wide range of frequency. The sensitivity seems to be high, enough, i. e., the output voltage can be measured with ordinary vacuum tube voltmeter when the sound pressure is such a value that yields ultrasonic cavitation, as in the most cases of applications of intense ultrasound in liquid.

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The biological regulatory system is opened by cutting at two points in the loop, and the external artificial system is connected between the two cut ends of the biological system. Thus a new control system whose overall characteristics is artificially modificable, may be constructed. Three series of the experiments using rabbit as experimental animal were undertaken.
1) The system of blood pressure regulation by carotid sinus was opened by cutting the connection between the systemic blood pressure, P_B (t), and intrasinual pressure, P_C (t), and is controlled by artificial system so as to maintain the required relationship : P_C (t) =f {P_B (t)} using computer, automatic control system and other devices. Because the original biological system has sufficiently large gain-and phase-margins, the loop gain can be much increased without the occurrence of unstability. The marked improvement of control characteristics was indicated by the increase of loop gain. If the system has a comparatively large delay characteristics, e. g. dead time is given by the insertion of dead time generator, the system falls into unstable state, hunting, and the undulative change in blood pressure was produced.
2) The system of blood pressure regulation via depressor nerve was examined. In this case the nerve was cut and stimulated with electric pulses the frequency of which was modulated by f {P_B (t)}. The improvement of control characteristics as well as undulative change in blood pressure were observed as shown in the first series experiment.
3) The system of regulation of respiratory movement via vagus nerve was modified.The vagus was cut, and its central cut end was stimulated by electric pulses the frequency of which was modulated by the required function of lung volume. The respiratory frequency was easily controlled, and the respiration thus produced (“electrovagal respiration” named by the author) was sustainable against severe disturbances. The electrovagal respiration may be used as an artificial respiration which is most physiological and most effective.

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To estimate cardiac electromotiveforce from electrocardiography, some methods which determine internal electrical sources from the surface potential of the human body have been analyzed. Body is approximated as a homogeneous conductor having a simple shape such as cuboid or cylinder. It is proved that the surface potential determines the potential in a harmonic region, and the sources such as point sources, dipoles, multipole, single layer or double layer, except some 3-dimensionally distributed sources. However, the distance between the source and the surface under consideration acts as a low pass filter for spatial frequency, and practically, the potential is measurable at a finite number of surface points, with various kinds of noise. Therefore, precise determination of sources is restricted by the accuracy of the measurement of surface potential.

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According to the Windkessel theory, cardiac output is proportional to dP/dt+P/τ, whereP, t and τ are aortic pressure, time, and time constant of the Windkessel respectively. On the basis of this theory, an analog computer was designed to compute stroke volume from aortic pressure. This computer may be calibrated by suitably infusing a known amount of saline into the aorta. The validity of this method was verified by measuring aortic flow with electromagnetic flowmeter in parallel with aortic pressure in a human subject during open-chest cardiac surgery.

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Factors regulating glucose biokinetics of non-anaesthetized dogs were studied using a ¹⁴C-glucose tracer dilution technique. The changes in plasma glucose level and rate of appearance of glucose were determined following the injection or infusion of various amounts of glucose. From the results of the experiments, a system of equations was set up using the digital computer, and their effectiveness in simulating the experimentally obtained results was tested. The proposed system has been found to give closely agreeing values for both rates of glucose production and the shape of the curve describing plasma glucose concentration versus time, confirming the reliability of the physiological basis of the equations. The equations proposed have proven successful in a number of different ways : (a) the same equations and the same numerical values of two parameters can be used in the same individual, irrespective of dose and speed of glucose administration; (b) the numerical values of the parameters vary within a small range between individuals; (c) the characteristic responses in the blood glucose concentration to an exogenous glucose load, such as secondary hypoglycemia, overshoots and oscillating leveling of blood glucose level, were also simulated by the equations ; (d) the intravenous glucose tolerance curve as well as the rates of appearance and disappearance of glucose can be simulated over a prolonged period of time.

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