A review on the rheology of blood and blood vessel has been given, stress being placed on the author's research area. Subjects selected are : 1. Non-Newtonian viscosity of blood, 2. Casson's equation, 3. Cause of non-Newtonian viscosity of blood, 4. Influence of plasmatic zone on apparent viscosity of blood, 5. Cause of appearance of plasmatic zone, 6. Sigma phenomenon, 7. Wall effect on apparent viscosity of blood, 8. Flow of liquid through a tapered tube, 9. Tension in blood vessel walls.
General formulae have been given for the flow and velocity distribution of a non-Newtonian liquid specified by an arbitrary flow curve f (τ) through a slightly tapered tube. These formulae are quite similar in form to those for the flow of a non-Newtonian liquid through a cylindrical tube.
A general theory of the tension in thick-walled blood vessels has been developed. The circumferential tension was expressed as a function of the internal and external. pressures and the internal and external radii of a blood vessel. The expression for the circumferential tension is reduced to the law of Laplace in the limit of infinitely thin wall. However, it has been found that the law of Laplace does not apply to thick-walled blood vessels. The circumferential tension may become even negative, depending upon the thickness ratio and the pressure ratio. Burton's theory of the circumferential tension in thick-walled blood vessels was criticized. It is really a question to introduce the concept of “pressure” in the interior of an elastic body as in his theory. It is shown that the circumferential tension which may be deduced from his theory does not agree with our general formula. Approximate formulae for the circumferential tension and the stress in the wall have been given, these quantities being expressed in terms of measurable quantities. A general theory of longitudinal tension has also been developed.

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Simulation techniques were employed in an attempt to reduce the waiting time for out-patients.
Seventeen clinical and administrative divisions in the Center for Adult Diseases, Osaka were selected as parmanent elements in the present simulation model.
The main routine of the simulation program consists of subroutines for the establishment of arriving time, service contents and their sequences as well as those of traffic control of each patient. Each arriving time is determined by normal random numbers. Service contents and their sequences are determined on the basis of uniformly distributed random numbers in terms of the probability presently calculated. The traffic control is. performed after patients' codes are subjected to schedules and queue tables with adequate changes in the computer memory.
Effects of changes on patient number, service time and traffic sequence were examined by means of the maximum and mean queues and the mean waiting time calculated by the simulator. Various improved methods were designed to reduce the waiting time of patients through the above procedure.
A traffic simulation approach has been found to be more practical than the queue theory in a complicated model. It seems promising in establishing an ideal hospital system.

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A digital computer program has been described whih is intended to serve as the basis for automatic interpretation of cardiac arrhythmias. Emphasis has been placed at this time on simulating and quantitatively determining human diagnostic logics with the use of only the temporal location of the P and R waves without regard to their shapes.Primary attention has been given in this paper to separating out and distinguishing between those “dominant” cardiac rhythms which are controlled by the sinus pacemaker (sinus rhythm group). Of 184 test cases belonging to the sinus rhythm group, 174 were correctly identified : 46 of 49 cases of regular sinus rhythm, 113 of 116 cases of sinus arrhythmia, and 15 of 19 cases of marked sinus arrhythmia.
Only 1 of 23 cases belonging to the complicated dominant rhythm group was incorrectly included in the sinus rhythm, eleven of total test cases of 207 were incorrectly diagnosed or could not be assigned a dominant rhythm on the basis of temporal beat distribution alone.
All occasional ectopic beats occurring in the tracing were correctly located in 168 of 184 cases of sinus rhythm group. In 8 cases, some of the occasional abnormalities were overlooked by the program, and in two cases, some parts of an example of marked sinus arrhythmia were mistakenly attributed to the presence of ectopic beats. Three fourth of all the errors encountered in this study were not due to program logic per se but could be attributed to the use of peak-to-peak rather than beginning-to-beginning interval measurements. It is anticipated that the concomitant use of information concerning the shape of the P and R waves would greatly reduce these kinds of errors.

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In this paper, an average response method is theoretically described for the systems including the variation of the dead time.
When the average response method is used for the systems in which a dead time element and a linear or zero-memory nonlinear system are connected in series, it is shown that the variation of the dead time is equivalent to a filter having an impulse response. The equation of the impulse response is represented by an equation describing a distribution of the dead time.
Some examples of the distribution function and their equivalent transfer functions are also given.
A manual control system is shown as an example of the systems including the variation of the dead time, a distribution function of the dead time of the manual control system and its equivalent transfer function are described.

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A new auto-scanner was developed with the purpose of automatic screening of cytological smears.
This apparatus is composed of an optical microscope with an automatic scanning stage, a TV camera as a morph detector and a computing system. The size and density of nuclei stained by Feulgen's reaction are transformed into video signal by means of the TV camera. The amplitude and the duration of the video signal are calculated by the computing system. The thresholds of the amplitude and the duration are previously determined by microscopic observation on malignant and non-malignant nuclei. If the information from a nucleus exceeds the thresholds, a signal lamp gives a red sign. The total number of red signs indicates whether the subject is malignant or not.
Up to now, vaginal smears of 1032 cases have been examined. All cases with uterine cancer were accurately diagnosed by this apparatus. A few false positive cases were, however, observed due to many clumpings of polymorphonuclear leukocytes in the smears.
Now we are planning to develop other advanced auto-scanners for mass-screening of gastric and lung cancers.

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Software system for MBE application which can execute information processing in conversational mode between the computer and the operator was discussed and constructed with the below-described features. (1) It was provided with ten useful macro instructions frequently used in MBE and six IO instructions. Both instructions and their parameters can be input to computer through a typewriter without any knowledge on programming. (2) A few optional instructions can be added by the code “OPT”. (3) Possible foolproof for operator is provided. (4) After instructions were input continuously, they were automatically implemented by the devised software named “Sequential Branching”. (5) By controlling the sense switch, data output and its calibration can be selected at will.
We focussed our efforts on the endeavour to minimize the memory allocation for storing the program in order to allocate 2.5 K words for data storage out of limited 4K word memory and yet provide enough information processing functions with the abovementioned features. Common use of program was adopted fully and some software techniques were devised such as the method of recognition of input code and that of type-outing the characters.

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The voluntary contractions of muscles generate specific patterns, related to the body motions, in the voltage fields on the skin surface. These patterns can be picked up through. multi-channel surface electrodes.
This report is concerned with the possibility of classifying these patterns and using them. as control signals for multi-functional system such as an artificial hand. The classification of the patterns is performed by the same method as in the learning machine. Myoelectric signals are fed to a computer, LINC-8, via an analog-digital converter and used as input variables for a linear discriminant function which is programmed on the computer. The learning procedure in this case is based on the error correcting training method.
The subject is asked to do a sequence of body motions. For each motion, the computer calculates the discriminants and categorizes the given pattern. If the answer is not correct, the weighting coefficients of the discriminant function are adjusted so as to approach a right answer.
In our experiments, seven kinds of hand motions were discriminated by using spatial patterns picked up from three surface electrodes on the fore-arm.

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