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Actin, a cytoskeletal protein, gathers and polymerizes under the cell membrane to mediate protrusion of the cell membrane. Therefore, actin participates greatly in cell movement. To quantitatively evaluate actin's dynamics during cell protrusion, movements of actin-labeled cells were observed under a confocal laser scanning microscopy, and time-lapse images were obtained. Image analysis of the orientation of actin stress fibers revealed dynamic formation of a meshwork of stress fibers in the protrusion structure at the leading edge of the motile cell. In addition, a number of immobile spots such as focal adhesions were observed adjacent to the dynamic meshwork of stress fibers. The distribution and the time between appearance and disappearance of each spot were analyzed. The results suggest that immobile spots close to the centroid of the cell play a crucial role in providing anchorage and driving cell movement.

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The accuracy of vision sensors and distance sensors to be used for environmental recognition is dependent on environmental condition. We propose method for generating 2.5-D map that includes information of impeditive bumps for autonomous mobile robots in outdoor environments. 2.5-D map has information of minute scale bumps which have a bad influence when a robot passes. We generate a 2.5-D map in real time with using the information of the image sensor and distance sensor while moving. Result of the experiment by the proposed method in outdoor environment shows highly precise and reproducible map generation is possible.

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Mobile robots need Simultaneous Localization and Mapping (SLAM) for autonomous movement in human living environments. The occupancy grid map used in SLAM is a conventional method which makes a map by an occupancy probability in each grid. This method renews a map based on whether an object is observed or not. In order to remove moving objects from a map an additional method is required. However conventional methods deal only actually moving objects, and potential moving objects (ex. standing humans) are mapped as static objects. Furthermore, only binary states, used or not used, are given to each object in map updating.
This paper proposes the immobility area grid map to represent a map by an immobility probability in each grid. The proposed method renews a map based on the identification of observed objects by robot's sensors, in addition to whether an object is observed or not. We introduce the map update parameter which is set adaptively from the certainty of identification result of the object. Observed objects can take continuous states, truly static - unknown - truly moving, according to the parameter value. Potential moving objects are not mapped if the parameter takes value corresponding to moving objects. The experimental results show the robust mapping in dynamic environments including potential moving objects.

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In this research, according to the stress coping style which used the hemodynamic parameter, I evaluated mode of viewing TV with the aim to estimate of the mode of viewing TV. The central nerves system was assessed by the Electroencephalogram (EEG). The autonomic nervous system were assessed by nasal skin temperature (NST) and Heart rate variability (HRV) with spectral analysis. In the spectral analysis of HRV, the high-frequency components (HF) were evaluated. The cardiovascular system was assessed by mean pressure (MP), heart rate (HR), stroke volume (SV), cardiac output (CO), total peripheral resistance (TPR). The multiple mood scale (MMS) and Visual Analog Scale (VAS) were administered to evaluate psychological status. As a conclusion, mode of viewing TV cannot be distinguished only with the preference to TV contents but it became clear that mode of viewing TV can be distinguished by the stress coping style with a hemodynamic parameter.

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Three-dimensional display technology has developed rapidly in recent years. There are also various types of telop, in which text information moves on a screen. We carried out experiments targeting about the 100 young and elderly subjects to verify the visibility of 3D images contained in text information. The aim of this study was to observe reading of the characters and how easy-to-read the display types were for 3D images. We examined the maximum distance in which subjects' eyes could recognize the 3D character representations without any difficulty or discomfort and validated popping distance using character information from 3D images that popped up from the background of stereoscopic images. We analyzed the effects of the virtual positions of the 3D texts. There was no significant difference between the theoretical and observed values in any age groups. We have found that even in the text protrusion of the large parallax, it is possible to recognize the position that pop out.

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In this study, we investigated expressive facial reactions in response to changes in the visual environment and their automatic extraction from sensors, in order to construct a comfortable level of illumination in personal living spaces. We conducted an experiment that showed that expressive facial reactions occur when illumination in the visual environment changes. We captured facial images and manually classified them as expressing or not expressing discomfort. We then conducted a second experiment that showed that automatic image processing can be used to extract and identify these expressive facial reactions. We extracted facial features and used a support vector machine to learn the classification in this experiment.

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In this paper, we propose a robust feature extraction method for color texture image based on multi-dimensional morphology. Multi-value co-occurrence matrix of multi-value morphology pattern spectrum of skeletons is used to represent texture structure. Color features are also extracted from RGB components based on similar binary morphology pattern spectrum. The extracted feature vectors have robustness to geometric distortions such as shift, rotation, scaling, skew, projection and their combinations. In simulations, robustness performance of the proposed method is verified to show the effectiveness under various distortion conditions. The effectiveness is examined by applying to image retrieval and classification systems. Accuracy of retrieval and classification is evaluated compared with those of HLAC based approach.

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This paper proposes a novel view independent vehicle make and model recognition method (VMMR). Our system identifies the make and model from the variety of viewpoints while the conventional methods for VMMR work only for the fixed frontal or rear images. In addition, it needs only the 2D images not CAD data for database. To solve the alignment issue, our method uses SIFT, that has scale and rotation invariance. For the view independent recognition, it creates less distorted frontal view images by view morphing or homography matrix calculated by the position of the license plate and extracts the keypoints from them. Our method enables to recognize up to 60-degree angle with high accuracy due to the less distorted virtual frontal images.

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Falls are very common among elderly patients in hospitals and nursing homes. Therefore, this paper presents recognition of getting-up motion which is an early indicator that can be used to help prevent falls. We propose a method for human action recognition based on patterns of motions. The method is constructed by autocorrelation of features extracted from edge direction and local intensity gradients. With the focus on the local regions of the image sequence, the features extracted by our proposal method are used as input information for AdaBoost. These features are turned to discriminate between different classes of action. We evaluate our algorithms on 95 video sequences, containing 31 getting-up motions and 64 different actions.

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In this study, we measured and compared the time resolution of the air conduction and bone conductive sound transmission by measuring the gap detection thresholds. It was found that the time resolution of sound heard through bone conduction is worse than that of sound heard through air conduction. Better time resolution was found in both ears than in one ear, in both air conduction and bone conduction sound transmission. In bone conductive sound transmission, the differences in temporal resolutions between the cases of one ear in the cases of both ears were larger than the differences when using air conductive sound transmission.

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Evacuation guidance and announcement are important for occupants to egress from buildings at emergencies. However, it is reported that the guidance and announcements have not been used effectively in real cases. NIST published reports on WTC collapse, September 11 2001. The reports include data on evacuation behaviors of the occupants and how they got information during their egress. After the Great East Japan earthquake, the Japanese Government conducted investigation how people behaved at the disasters. The evacuation behaviors of people are similar to both cases. The behaviors are categorized into three groups; instant evacuation, evacuation after tasks and emergent evacuation. We present a system that evacuation guidance is implemented as a way of agent communication and show the contents of the guidance change the escape time.

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In this paper, we propose a transversal adaptive equalizer using the least mean squares (LMS) algorithm for digital power line carrier systems and discuss about the optimal number of taps, the step size parameters, and the achievable bit error rate (BER) performance. First, we present two power line models: Model 1 with a line trap on the power line branch and Model 2 without a line trap on the branch. Then, we present theoretical analysis and the computer simulation results. In the case of Model 1, the sufficient number of taps is around 12, while in the case of Model 2, it increases to 21. This is because a line trap in the case of Model 1 can suppress the electric energy of the delay path. It is desirable to change the step size parameter µ in the training and tracking modes in order to achieve fast mean square error (MSE) convergence rate and a good BER performance; i.e., a relatively large value of µ=0.01 should be used in the training mode while a small value of µ=0.001 should be used in the tracking mode.

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There is increasing need for magnetic resonance microimaging (MRMI) measurements of tissues and cells of organisms to be nondestructive and accurate. However, no objective method is yet available for evaluating the spatial resolution of MRMI. Therefore, this study attempted a simple evaluation of spatial resolution of MRMI captured by 3T MRI of clinical equipment. In this evaluation, a phantom was inserted into an NMR tube (outer diameter 10mm) filled with copper sulfate solution. The phantom is a double structure comprising a thin capillary tube inserted in a thick capillary tube. The outer diameter of the capillary tube was measured using a micrometer. Images of the capillary tubes were captured using image-processing clinical 3T MRI equipment. From the captured image, the outer diameter of the inner capillary tube and the inside diameter of the outer capillary tube were determined. The outer diameter of the outer capillary determined from the image was nearly consistent with that measured using the micrometer; therefore, the capillary tube method was confirmed as being reasonably accurate. Further, the MR image captured by the clinical 3T MRI equipment was found to have a spatial resolution of about 20-40µm.

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In a college of clinical engineering, the students have to receive practical training and clinical skills. During practical training, the students sometimes have some troubles about their mood or anxiety. In this research, the psychosomatic states and autonomic nervons system of the students were evaluated before, duning, and after the training. This study examined changes in the mood and anxiety states and the pulse wave associated with workload in students at a clinical engineering training college before, during, and after clinical practice. The subjects were 10 healthy adults (7 males and 3 females; mean age, 24 years). The Profile of Mood States (POMS) and the State Trait Anxiety Inventory (STAI) psychological tests were administered before, during, and after clinical practice, and the autonomic nervous responses were evaluated by measuring the digital pulse volume under calculation and eye-closed resting. The results of the psychological tests showed a higher level of nervousness, anxiety, and fatigue during the clinical practice than before the clinical practice. The autonomic nervous responses showed a state of sympathetic dominance before the clinical practice and that of parasympathetic dominance during the clinical practice. These findings suggest that monitoring students' psychological states and stress conditions by performing POMS and STAI and evaluating autonomic nervous responses before and after their clinical practice is beneficial for students' own stress management as well as mentors' coaching purposes.

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The aim of this study was to characterize the neural activation that was associated with the performance of intellectual activities under the influence of Brownian noises that were similar to environmental noises in real spaces. An N-back task comprising 2 components, i.e., verbal and spatial tasks, was used to study working memory during 4 types of auditory stimuli. The 4 types of auditory stimuli were as follows: sounds with frequency characteristics of Brownian noise [No Modulation (NM)] and with their amplitudes modulated 0.05-1 Hz, and sounds with frequency characteristics of White (slope of power spectral density, 1/f⁰), Pink (1/f), and Brownian noise (1/f²). Event-related potentials (ERPs) were recorded from 60 electrodes on the scalp and analyzed. Seven healthy men who were 21-23 years old participated in the experiments. For the NM, the root mean squares (RMS) of the ERPs that were observed included a negative peak component around 150 ms in the parietooccipital area (N1) and a positive component around 330 ms in the centroparietal area (P3) in both tasks, as well as for other auditory stimuli. The White modulation sound was the most influential, with a P3 amplitude in the spatial task in the frontal and central regions. These results suggested that the White sound during a spatial task affected the neural activation that was associated with attention accompanied with working memory activity in the N-back task.

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Due to the amplitude-frequency characteristic of the steady-state visual-evoked potential, the flickering frequency of a steady-state visual-evoked potential-based brain-computer interface is typically lower than 20Hz. However, a visual flicker with a flashing frequency below the critical flicker-fusion frequency often makes subjects feel edgy and causes visual discomfort. This study aims to quantitatively evaluate the relationship between user's visual discomfort and the nasal skin temperature (NST). NST is calculated using the thermal image of the human face. The correlations between the physiological index (NST) and the psychophysical index (based on responses on the visual analogue scale (VAS)) were both considered. The results of VAS are a psychometric response index, which can be used in questionnaires.
This study presents a novel technique based on the nasal skin temperature to measure user's visual discomfort. A change in temperature was studied in accordance with the usual method. The results were similar to the known symptoms, which are related to optical sensitivity. Moreover, the frequency characteristics of NST were studied. As a result, the relationship between user's visual discomfort and frequency characteristics of NST dynamics is very strong under 0.01Hz.

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This paper focuses on mobile robots that can accompany a person, that is, it addresses how to control the relative position of the robot to the accompanied person according to the dynamic environment. The robot is expected to move side-by-side with the person in the normal situation, but the position in front or behind the person might be better if there are some obstacles. The shape of the artificial potential field of the accompanied person is devised to smoothly control the robot position in a unified way. Laplace potential method is also used subsidiarily to cope with extremely cluttered environments. Simulations and experiments in real space show the usefulness of the proposed method.

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Research on human interaction is done actively in recently years, and activity of robot is expected in various scenes. For example, the robot which guides facilities while regarding communication as a human being or the robot is intended to play with a child. We paid our attention to the interaction for purpose of enjoying turn-taking. We believe that it is necessary to reflect the preference of the user for an interaction so that a user has a positive impression for the system through such an interaction more. This research aims at development of the human interaction system which a impression for the system of a user improves by the system reflect a preference of the user, and emergence does a better interaction for the user. The user gives an evaluation to the interaction that the user and the system performed, and the system learns it dynamically. The system carries out emergence of a better interaction for a user. This report pays attention to simple interaction by the sight, and inspects effectiveness of the proposal method in interaction using simpler symbol.

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To evaluate performance of a large scale digital system, the system is modeled by stochastic timed petri nets (STPN) and performance index is estimated through iteration of a petri net simulation. When the performance evaluation is carried out in a large distributed environment, parallel calculation with incidence matrices of STPN can make the petri net simulation more efficient. In this paper, we proposed an ordering method of incidence matrices to reduce the communication costs in the parallel calculation of matrix operations. For this purpose, we first proposed a method for blocking the incidence matrices based on a structure of a system by considering synchronous and asynchronous buses as composing elements. We also proposed a method for converting sub-matrices of incidence matrices to band matrices. This method is based on the bread first search of STPN represented by the sub-matrices. Finally, we demonstrated an effect of the ordering on the time for performance evaluation by carrying out the performance evaluation using incidence matrices generated by the proposed method. In addition, we showed that the ordering method could reduce the communication costs in a large distributed environment by estimating the use rate of calculation nodes.

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For mitigating the negative impacts of high penetration photovoltaic power generation systems on the existing electric power system, the increase in the daytime electricity demand by the shift from the night-time or the other energy use is essential. Focusing on a heat-pump water heater (HPWH), this study proposes an autonomous scheduling method of the daytime operation of HPWH. In the proposed method, the reference stop-time is determined based on the past hot-water demand. The actual start-up time and stop-time varies with days depending on the change in the amount and the timing of the hot-water demand with days. The proposed method was tested by using the hot-water demand observed in 12 households for a year. As a result, the ratio of in-use HPWHs increases lineally with the increase in the extraterrestrial irradiance when the extraterrestrial irradiance is larger than the certain value. The sudden increase and/or decrease in the ratio of in-use HPWHs are avoided by dispersing the reference stop-time depending on the amount of hot-water demand. Consequently, the numerical simulation shows that the proposed autonomous scheduling method effectively works to schedule individual HPWH so that total number of in-use HPWHs follows the daily change in the extraterrestrial irradiance.

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This letter presents a design of low power dissipation and small die area 10-bit capacitive digital-to-analog converter (DAC) for Bluetooth applications. By using three-level operation, the number of capacitor can be reduced. Thanks to differential operation of the designed DAC, it is no need to implement common mode reference voltage generator circuit. Moreover, in this design, optimally designed common mode capacitor is used to suppress common mode voltage drift. The fabricated chip achieves the best figure-of-merit among published DACs for Bluetooth applications.

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The event-related potential (ERP) when subjectively judging the appearance of food was measured by four tasks with changing the number of displayed pictures corresponding to each opinion; “like”, “favorite” and “more favorite”. Sushi was selected as a typical food. The results indicate that the use of a task with one piece of food picture corresponding to each opinion “more favorite” and “favorite” will be suitable.

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