[in Japanese]

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In contemporary society, an increasing number of people have excessive stress which affects their physical and mental conditions. As for methods of alleviating stress, listening to music and aromatherapy can be cited. These are expected to be applied to complementary alternative medicine because they can be easily handled. However, the effect depends on sensory evaluation. In this study, oxygenated hemoglobin (Oxy-Hb) concentration in the prefrontal cortex was measured by applying auditory or olfactory stimulations to an organism during a time of rest and stress using near-infrared spectroscopy. (1) An experiment that applied rest and stimulation alternately and (2) an experiment that applied stress and stimulation alternately were conducted for 10 subjects (6 male and 4 female). During rest time, subjects were asked to repeat counting from 1 to 10. In experiments with auditory stimulation, three kinds of music with 1/f fluctuation were listened to by the subjects. In olfactory stimulation, three essential oils which are supposed to have a relaxing effect were inhaled. The stress time allowed subjects to perform one digit of mental arithmetic. The Oxy-Hb concentration change decreased with time when auditory stimulation in (1) and all stimulation in (2) were applied. In addition, the mean values of Oxy-Hb concentrations at rest, stress, and each stimulation were calculated, and the differences were compared to evaluate each stimulation. In the case of (1), Oxy-Hb concentration decreased at auditory stimulation time in comparison to rest time. Oxy-Hb concentration was confirmed to decrease in all stimulations in (2). Oxy-Hb concentrations in both experiments were compared using a t-test. Significant differences in Oxy-Hb concentrations were observed in the left prefrontal cortex for all the stimulations (p<0.05). Therefore, it can be suggested that the stimulations used in this experiment are effective in alleviating stress.

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In this paper, the effect of boiling treatment upon the distribution of selenium and mercury in the edible tissues of the short-necked clam Ruditapes philippinarum was investigated in relation with each elution profile of both elements to the cooking liquid (generally called "Kaijiru" in Japan). During the boiling treatments (5 min, 10 min, 20 min and 30 min at about 90 ﾟC), the variation of both levels were not apparently observed in the edible tissues, however, the level of dissolved selenium in the cooking liquid tended to increase slightly with time. The chemical species of the dissolved selenium was mainly organic. On the other hand, dissolved mercury was not detected from the fact that the mercury level was extremely low in the edible tissues. This suggested that a trace amount of Hg-Se complex as a final detoxified substance was not excreted out of body by means of the boiling treatment. The Se/Hg value (the molar ratio of selenium to mercury) in the edible tissues of the short-necked clam as an indicator of the safety of marine products was almost constant (about 100 1) through all boiling treatments, and then the safety of mercury in the edible tissue was confirmed against the boiling treatments.

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IoT has been rapidly spreading in recent years. In particular, the spread of IoT to the socially vulnerable is expected to realize advanced social inclusion. However, it is difficult for the physically handicapped people to operate the IT terminal. In this research, we developed a pointing device that does not require limb movement. In this device, the cursor is operated by swinging the head, and the click is operated by surface-EMG. Moreover, pointing performance was evaluated according to ISO 9241-9. Experimental results show that the Throughput value is about 1.5 bits/sec and has pointing performance according to the remote mouse for presentation. In addition, the malfunction rate was different among individuals. This cause is presumed to be due to individual differences in occlusion, suppressing malfunction by training is expected. From these result, it is expected that the device will be useful as a pointing device for physically handicapped people.

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This study was performed on students (elementary, junior high school and high schools) who attend cram schools to evaluate how various types of wall material influence on their learning and general impressions. Students attend cram schools to improve their academic skills, demonstrate better grades through routine testing, and to pass entrance exams to get into high schools and universities of their choice. Another role of cram schools is providing an environment where learning can take place. The number of cram schools offering rooms and spaces for quiet independent study is increasing. These schools are now required to provide a space where students can study comfortably for long hours. We therefore, created a study room with interchangeable wall material, based on our belief in the connection between wall material and better grades. Among various wall materials, we focus on the bamboo charcoal that has beneficial effects such as deodorizing, humidity control and shielding electromagnetic waves. Bamboo charcoal is used in a variety of fields including environmental and medical for its numerous benefits. Among those, application of bamboo charcoal in residential environments is drawing much attention. It has been used beneath floors to adjust humidity in Japan, which has very high humidity. Its recent application in interiors has boosted the development of bamboo carbon paneling and cardboard. In this study, we surrounded the walls (except the ceiling) of the cram schools attended by many of the students with bamboo carbon paneling or boards. The students are allowed to study freely in this space. We tracked the transitions of their grades and assessed their impressions while they were studying in this space.

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The purpose of this study was to analyze the traveling motion by a running motion analysis device (sensor device) using an inertial navigation system with a proprietary triaxial acceleration sensor and gyro sensor and 3 dimensional motion analysis system (VICON). The validity of the sensor devise as a motion analysis device was examined by comparing the analysis results of the running motion. As a result, the intraclass correlation coefficient (ICC) was 0.9 or more at speed, vertical motion, contact time, brake, landing angle and kicking out angle. The degree of agreement between the above two analysis index values between the two devices was regarded as excellent. By Bland-Altman analysis, it was recognized that the degree of coincidence of each analysis index value was high, and the difference was confirmed to be within the error range. In some items, the sensor device was more accurate than VICON and the possibility of measurement could be considered sufficiently. From the above results, it can be said that the accuracy of the sensor device developed independently and the accuracy of the algorithm used for motion analysis were recognized, and the validity as a motion analysis device was recognized.

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New utilization of rice hull, which is one of the agricultural waste in Japan, is required from a viewpoint of the recycling. The authors have developed porous carbon material (Rice Hull Silica Carbon: RHSC) made from rice hull. RHSC is manufactured by mixing and impregnating the rice hull particles with a phenol resin, pressure forming, drying, and then carbonizing it in the nitrogen gas atmosphere at high temperatures. Since the rice hull has a natural porous structure, the RHS carbon is manufactured as a porous carbon material. RHSC has core competencies such as low friction coefficient and water resistance, and it is expected to be applied to linear guide elements and sliding bearing. However, RHSC has pores generated during the manufacturing process, and it is considered that the reliability of strength is lower than commonly used sliding member. In this study, the authors carried out a fatigue test, evaluated of fatigue strength of RHSC and elucidated influence by size effect. The strength of RHSC tended to depend on bulk density. In addition, the authors in order to confirm the characteristics of the test piece broken at a low number of cycles, fracture surface was observed by scanning electron microscope. Moreover, pores were observed on fracture surface of test piece, and RHSC was clarified that pores in structure of RHSC influences the fatigue strength. Therefore, it is suggested that the reliability of RHSC can be obtained by stabilizing the bulk density.

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"Yutori Education", or pressure-free education, that was proposed in Japan in the 1980s led to a significant reduction of learning contents and teaching hours in schools, and the introduction of the five-day school week. According to the results of Programme for International Student Assessment (PISA) that has been conducted by OECD (Organisation for Economic Co-operation and Development) every 3 years since 2000, the rankings of Japanese students dropped dramatically since 2003. In reading literacy, the ranking of Japanese students dropped from No.8 in 2000 to No.14 in 2003 and No. 15 in 2006. And in math literacy, it dropped from No.1 in 2000 to No. 6 in 2003 and No. 10 in 2006. These outcomes brought a discussion about the issue of academic ability decline caused by the reduction of learning contents and school hours under the governmental education guideline of "Yutori Education". In response to this situation, the 2008 governmental education guideline titled "Break from Yutori Education" advocated nurturing of "Living Skill" and reformed teaching toward "Acquisition of Basic Knowledge/Skills". It included a significant change of direction such as increase of school hours and learning contents. For acquisition of basic academic skills, it is thought that nurturing of thinking ability, practical ability and expressive ability is required to improve the comprehensive academic ability. In this study, we focused on the cognitive process of the learners during their learning for academic improvement, and examined the studying method that could connect the learning material with the individual knowledge of each learner. Concretely, we examined how the learning method using highlighter pens, which are used to improve the effectiveness of learning through the visual effect of coloring texts, influences the cognitive process during learning. Focusing on the number of eye movement and the fixation duration of line of sight, we attempted to develop the evaluation system for such examination.

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The bromide ion analysis method in beverage raw water by liquid chromatography/tandem mass spectrometry (LC/MS/MS) was examined, and its validity was evaluated by addition recovery test. As a measurement condition, a multimode column reversed phase + anion exchange resins, into which a quaternary ammonium group was introduced, were used for the purpose of appropriately separating for high朴olarity bromide ion and other ionic compounds on the chromatogram. The calibration curve of bromide ion showed good linearity in the concentration range of 0.5 to 10 ｵg/L, and the repeatability (RSD) of the 1.0 ｵg/L bromic acid standard solution was good (2.4 %). Furthermore, as a result of the addition recovery test (n = 7) of ground water, the results for bromide ion in tap water showed that the recovery efficiency was 90 % and the RSD was 1.4 %, and satisfied results were obtained for the real samples.

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This study aims to develop a system to recommend an adequate difficulty level of music which suits a preference of a self-learning piano student. First, a user input a group of favorite music into a system and the system arranges the music according to the difficulty level. Next, the system analyzes the proficiency level of the user and recommends the music with the difficulty which is most similar to this level. With this system, users can select their practice music from the group of music arranged according to the difficulty level. In this paper, the authors used following procedure: first, a group of music from a piano manual which arranged several pieces of music according to the difficulty level are registered into a system; next, the system selects a piece of music based on the preference and the proficiency level of the user. The proficiency level is judged by whether the user can play the selected music or not. We proposed two algorithms to estimate the similarity of the difficulty level of music: One employs nearest neighbor algorithm and the other utilizes neural network.

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[in Japanese]

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Top athletes use pre-performance routines to improve their performances. We here examined whether pre-performance routines improve accuracy in the tasks performed by non-athletes. Thirteen non-athlete students were subjected to darts, arithmetic and memory tasks after pre-performance routines. The non-use of pre-performance routines was used as a control. The levels of concentration were assessed with the electroencephalography. The use of pre-performance routines significantly increased the levels of concentration during the darts and the memory tasks. Moreover, pre-performance routines also significantly improved the accuracy in the darts task. These findings suggest that pre-performance routines have potential to improve concentration and task accuracy even in the non-athletes.

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