Recently, study on CAD system is addressed. The CAD system can assist to medical doctor for diagnosis in visual screening. Temporal subtraction method is the one of techniques for implementation of CAD. The temporal subtraction method, which enhances temporal changes such as new lesions, is useful for thoracic CT diagnostic imaging. To achieve a temporal subtraction method, image registration technique is required as essential procedure. If the image registration procedure is implemented insufficiently, subtraction artifacts are remained as the result of miss-registration on temporal subtraction image. Also, in the case of using thoracic MDCT, 3-dimensional image registration is applied for temporal subtraction method. However, because of the complication of temporal deformation on 3D region, large amount of calculation costs are required for the image registration between current image and previous one. In this study, to reduce computational time for temporal subtraction on thoracic MDCT, we have developed hierarchical 3D image registration method based on octree data structure. Some experimental results are shown with discussion.

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In the system to search for a target image using IGA (Interactive Genetic Algorithm) that we have been developing, a user first selects one individual resembling a target image most and gives it fitness 1.0, and others are assigned with fitness calculated based on the relationship between the selected individual and the others. Although this system asked a user to do only simple task that is selecting one sample, all users weren't happy. There are a few reasons for this. It is sometimes difficult for a user to select only one individual. Sometimes, a couple of individuals may equally resemble a target image, or no individual may have a close resemblance to a target image. In these situations, a user wants to select a few individuals, or to say it doesn't resemble a target image very much, or it only slightly resembles a target image. In this paper, we propose a interaction strategy that is able to deal with the situations and evaluated the validity of the strategy using computer simulation. As a result, we found out useful an interaction method and a fitness assignment method.

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The approach of the Web accessibility is necessary for all the people to be able to use websites. As the visual elements are very important factors in the website, in our previous study, the visibility of young adults, the elderly and dichromatic vision was evaluated using the simulation filters. And we made a model of linear discriminant function for predicting the website visibility. In this report, in order to improve the visibility predictive formula, we made a model of quadratic discriminant function. And the accuracy of the calculated predictive formula was evaluated based on the visual feature. As the results, both discrimination functions had a high correlation with the visual feature. However, the correlation of the linear discriminant function was stronger than the quadratic discriminant function. Therefore, it was shown that the linear discriminant function strongly reflected the visual feature.

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Medical students need to pass a nationally licensed and recognized national exam before their graduation. They take the national exam across Japan in late February. There are several studies that have examined the stress level of the students while preparing for the exam. However, there are few reports about support given to those students in order to alleviate their stress. In this study, 16 students while preparing for the exam were recommended to take a 30 minute rest in bed. In order to assess their stress levels, cortisol levels in their blood were measured. As a result, 11 out of 16 students had a decrease in cortisol levels; however, the rest of the students did not. This study concluded that taking a 30 minute rest before the exam leads to the reduction of students' stress levels. With regard to the students who did not have a decrease in cortisol levels, other factors need to he analyzed.

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Blinking can be used as a biological indicator of consciousness, concentration power and Visual Load. We develop a technique to obtain the number of blinking during the VDT work easily and without restrictive measurement method. In the technique, images from a generally utilized Web camera connected to PC are processed to detect the blinking. The template matching method for the image is used to track the eye region and the upper eyelid which moves up and down when blinking. In the previous paper, the accuracy of blinking detection was over 90% at the capture resolution 320×240 [pixel]. However, when the capture resolution was set even lower, the tracking accuracy of the upper eyelid inside the eye region deteriorated extremely. In order to improve the tracking accuracy, the continuous change of the number of pixels which corresponds to the size of pupil and iris within the eye region is used to detect the movement of the upper eyelid. Therefore we examined whether the fatigue estimation of VDT work by measured Eye-Blink.

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In this research, we have experimented with assuming a collision or fall with of dummy at JARI. Various experiments can be used to evaluate the safety in this situation. Crash dummy experiments are especially used to assess the risk of potential damage for driving and boarding People. We attempt to know the physical strength of human organs and their coefficients. We searched the physical and initial conditions of numerical analysis. The data, which we obtained from dummy's experiments, were useful for determination of anatomical trauma scales.

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medical accidents by falling fracture, it is tend to increase every year. According to the previous year is due to falling fracture about 30% of medical accidents. Medical institution, falling fracture countermeasure is an important issue. We are elucidate behind falling that had to give a serious head injury by previous studies. In this study, we conducted a survey of head injuries effect due to falls by floor material and falling posture. As a result, the angular velocity in head injury risk is high, regardless of the floor material. the HIC showed no difference floor materials.

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We will have much experience of human mechanical injury when we live together with various robots in daily life. When our bodies were given same energies of mechanical impacts by robots, parts of our bodies had serious damages in proportion as proper characteristic of organs. And our organs had proper waveforms of impacts and we need proper criterions for proper organs. We proposed the analytical models of human falling and hypothesis of the rotational & free falling of human bodies, and estimated the grade of organs' damages, head, chest, abdomen, and femoral region. Our serious damages of falling, fracture of head, chest and lacerate wound of abdominal organs were occurred by mechanical impacts. Especially head injury was estimated by HIC, however, which was not he able to apply for the other organs, and used proper criterion for various organic damages. And We knew, antagonist muscles, biceps femoral m. & rectus femoral m. worked together and had oscillation motions, in order to absorb impacts as if antagonist muscles were made to be formed as a kind of bio visco-elasticity.

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Accidents of fall & descent sometimes cause serious injuries, which propose us criterion-models of human biomechanical impacts when various robots will come into future daily life. The collision's experiments using dummy dolls, which were supposed to direct contact between human bodies and robots, were performed in co-operation with JARI. And theoretical models based on the experiments, which we thought to describe processes of the accidents of the fall & descent, were proposed. The worst case of the fall & descent in our daily life were assumed to be the fall & descent from on high, (for examples, bicycle, footstool, carriage, and chair, steps), and we attempted to estimate biomechanical Impacts and injuries by doing experimental image analysis. Finally, we found to he approximately expressed the fall & descent of human bodies as motions of ridged bodies and proposed a theory of rotation & free fall for human heads.

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Human injuries of damages were two major factors. One was a set of physical factors and another was a set of biological & medical factors. The set of physical factors was composed of about four factors, which mainly corresponded to the height, area, weight and collision-time to govern external impacts for human bodies. The biological factors to be based on individual differences were so complex that it is not easy to research the estimation of organs damages. Adopting anatomical criteria, AIS or HIC and using those s set of physical factors, we can easily attain the average damages of human bodies, however, the estimation of individual damages is no so easy to do. We can obtain the important values of the collision time and impact responses with using the impact-falling test, which is a kind of excellent nondestructive tests.

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It is difficult to obtain dynamical coefficient of viscoelasticity when we attempt to practice a simulation of human bodies and organ's injuries, because of a ethical problems for those experiments. We proposed the experiments, which we used biological samples on the market and impact-falling testing machines in order to guess the time-dependent coefficient of viscoelasticity. Impacts-response data (breaking accelerations and responses of load-cells) to be obtained from those experiments was divided into many small time-intervals, and those data assumed to correspond to the terms of the breaking accelerations and to responses of load cells-external forces of our differential equation. The measuring method of time-dependent coefficient of viscoelasticity was very simple ideas, however, we paid attention to adjustments of biological samples and to the intervals of time separations.

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The human injuries were composed of two sets of various factors, which were a set of physical factors and that of biomedical factors. The physical factors were simply determined by four factors containing the collision's times (impact response time), an area of injury, height of falling and weight of injury's region. The injury' criteria, AIS and HIC were calculated for average Japanese men and women by adopting hypothesis of free falling & rotation, and those physical four factors. The most severe case of falling and descent was to be colliding with both big dummies. The injury of AIS>4 gave rise to the fetal traumas in the head when the big dummies collide with each other at speed 5km/h. We can efficiently reduced the lethal rate of traumas when we worn protectors made up Styrofoam. However, I was desirable to improve our present protectors since we sometimes had large outliers of impacts.

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The present study examined the influences of slope gradients and the direction of wheelchair travel on the user's riding comfort, as well as postural change and physiological values during wheelchair locomotion on a longitudinal slope. On both uphill and downhill slopes, steeper gradients enhanced the postural change of the user. On steeper downhill gradients, going down the slope backward decreased user's heart rate. On a downhill slope with a steep gradient, especially slope gradients steeper than 1/10 or more, going down backward would be a useful technique to stabilize user's posture during wheelchair locomotion.

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This paper describes studies to understand the fundamental mechanism of the collision and fall induced human injury by using dummy in the experiment. In our dummy experiments, the dummy on the cart is collided by the other dummy and fallen on the floor It is concluded that (1) the time interval of these two forces was 800ms, and it is possible to use this interval for developing safety devices for these human falls, (2) the injure criteria was effected by the initial position and pose of dummy, (3). HIC (Head Injury Criteria) decrease under the safety area with helmet in all cases of these dummy experiments.

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What is time? This question has been considered philosophically since ancient times. In 20the century, theory of relativity has been constructed in the field of physics by Albert Einstein as everyone knows. One result of this theory is that it is meaningless to think about time independently from space In this way, profound natures of time have been elucidated. Nevertheless, there is a big problem in the concept of time in relativity. All natural science including physics have same problem. This sort of the concept of time is objective and there is essentially no difference between the past, the present and the future. However, it is different from real daily experience in human life. We are always conscious of only "now". The past and the future can be only imagined, not experienced. The psychotic disease such as schizophrenia makes these facts remarkable. In this article, we will illustrate difference between physical time and "experienced time" explaining psychotic symptoms such as depersonalization psychopathologically. Furthermore, it would be expected to get more profound understanding about the concept of time.

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In geriatric medicine, fall is a very important problem as well as dementia, being bedridden and incontinence. The serious damage such as fracture and subdural hematoma sometimes follows fall and brings about being bedridden. Being bedridden is also a risk factor of dementia. This condition needs great care and medical treatment. Therefore, the prevention against fall is a very essential problem in geriatric medicine. We investigated the actual situation of fall in several psychiatric hospitals in this study paying attention to age, posture and place in falling. At a result,the occurrence ratio of serious damage brought about by fall is about 16.5% in one hospital and about 4.5% in another hospital. These results are comparable to preceding investigations. The factors of place and posture in falling have no relationship with this occurrence ratio. Aging has been found to be the factor reducing this ratio. This result fell short of our expectations. Generally speaking, aging is thought to be a risk factor of fall. In many hospitals, many measures have been taken against fall, especially for elderly patients recently. Our results may be caused by these measures. It would be thought that places in fall should be classified into various categories according to materials of the floor.

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Handball Games is a basic human behavior "Run", "throw", "jump" for a sports. Handball Games, attention has begun to incorporate new course of study is being evaluated this. However, Japan Handball could not get results at the recent world championships. Japan Handball Association felt this sense of crisis situation. And Japan Handball Association starts up NTS (National Training System) and is aiming at "Talent excavation", "training", "strengthening". In the present study, the game of the Fukuoka student selection team and the Korea team of Asia top-level was investigated. And in order to obtain a score in a game by multiple linear regression analysis, it argues about whether a characteristic play and skill exist. As a result, It turned out that a score is related to the breakthrough method, a breakthrough position and a foul, the times of a path, etc. The attack which was being subjectively expressed by this was able to be shown quantitatively. Use this index could indicate a strengthening of the team and evaluate the game.

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We defined Collision Impact Index (CII) of each part of human body due to falling down. The formula of CII is defined similar to HIC. The meaning is "Powered averaged acceleration and the time product". In order to make clear the usefulness of the Index CII, the experiment was done in JARI, and the acceleration data are taken on the head, chest and pelvis of a dummy robot, which simulates the human body. The acceleration data was measured in the step of 0.0001 second, and analyzed on the basis of the proposed formula of CH. As a result, it is shown that index CII is important for recognition of the peak pattern because (1) the ratios are similar dependence in spite of the power, (2) only peak is selected by the power, (3) the selected time intervals are almost constant, although the width becomes narrow as the power goes large.

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