Fumihiko Yano

A time variation of professional driver's EEG in monotonous work

An experiment was conducted on five subjects to determine the time it takes for slow alpha wave activity to appear during monotonous tasks. The experiment measured the time of response to digits appearing on a screen and the time of appearance of slow waves in the electroencephalograms (EEGs). Two professional automobile drivers were tested, as well as one maintenance technician and two students for comparison. The EEGs were analyzed using the autoregressive method. The results are presented and discussed.<<ETX>>

The Arresting Effect Of Fragrance On Inclining Sleep

In this paper we describe the arresting effect of fragrance on inclining sleep(The inclination to sleep), and list some of the basic data. It has been firmly established that Grouped Slow Alpha Wave appear in the EEG(e1ectroencephalogram) when one falls into the state of inclining sleep, indicating a drop of brain activity. It has also been reported in recent studies, that the stimulus of fragrance has various biological effects on human beings. An experiment, arresting the effect of inclining sleep followed with a drop in brain activity, was performed. The results were estimated by using Grouped Slow Alpha Waves. The fragrance stimuli in this experiment were Lemon, Jasmine and Lavender, and the results were as follows:

A detecting method for the fetal QRS complex with a small amplitude

It is often impossible to determine the presence of the fetal QRS waves from leads on the maternal abdomen because the amplitude is small or noise interferes. Yet, clinically, confirmation is highly necessary. Clinicians face a great difficulty when the fetal QRS waves are not identifiable: when, for example, they are not apparent owing either to the fetal death or to the poor recording system. We therefore developed the fetal QRS complex detecting system for computer use. This system was developed through the use of two procedures. First, possible fetal QRS waves were detected by computing slopes of moving regression lines. Second, the location of the fetal QRS waves was determined from possible fetal QRS waves by using the weighted periodgram method. We recognized that this system can detect fetal QRS complex from fetal ECGs that are affected by mixture noises in the fetal ECGs accompanying both cephalic and breech presentations.

An image analysis of fundus photograph

The authors have developed a system for the classification of fundus findings in the examination of cerebral hemorrhage and for the support of the image analysis. This system recognizes the position in the blood vessel in the image, codes the pattern information, and compares the image with already stored images on the basis of the coding patterns.<<ETX>>

Automated Image Analysis Of Fundus Photographs For Mass Health Screenings

As the use of non-mydriatic wideangle fundus cameras has become widespread, a large number of color fundus photographs are now routinely taken during group health checks. Since many tests have to be performed at one time on a large number of people during group physical examinations, a utomation or simplification of these tests is important. Bearing this in mind, we recently experimented with an automated image analysis of color fundus p hotographs (taken during group health checks) with a low-cost s ystem using a personal computer. The following results were obtained: (1) By moving regression planes, corresponding to minute segments of the image, vascular edges could be detected without any limitation as to the direction of approach. (2) Data transformation into Y.1.G signals with the NTSC (National Television System C ommittee) method allowed for e ffective e xtraction of vascular patterns without being affected by color changes. (3) Chain c oding of the extracted vascular patterns r esulted in reduction of the data to about 2% of the original

Multistage signal extraction method with spline filter

As is often the case, experimental data contain various superimposed signals, from which the required signal or signals must be extracted. In such cases, the required signal level has not always been higher than the other signal levels. Therefore, it was difficult to eliminate all unnecessary signals using conventional noise elimination methods by classifying unnecessary signals as noise. To overcome such difficulties, a multistage signal extraction method is suggested which extracts the desired signal component by applying the filtering in multi-stages. The results extracted by this method contain only the required signals plus the noise with the same amplitude readings. This makes it easier to reduce the complexity of signal extraction in later stages, such as the signal extraction based on other data information. In this study, a spline filter is constructed using the cubic B-spline smoothing process, which has versatility and is employed widely as a practical method. The multistage signal extraction method has versatility, and filters other than the spline filter can be utilized if the waveform is not overly distorted.

A study of short term memory-character presentation and masking stimulus time, and their order

The purpose of this study is to determine what factors influence short-term memory, for a short time that may or may not equal the presentation time. Six or seven English characters are presented for a short time sequentially and at the same position on the display of a CRT. A masking stimulus is presented along with the characters. It is found that: (1) The total presentation time, which is the sum of the character presentation time and the masking stimulus time, has a great effect on short-term memory. (2) A masking stimulus is profitable for short-term memory. (3) When the ratio of character presentation time to total presentation time is large, it is favorable for memory. (4) It is not always favorable for total presentation time to be too much longer.<<ETX>>