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Fall risk assessment is important, because falls for the elderly account for 12% of the factor of needed LongTerm Care. The plantar pressure during walking is responsible for gait movement, and fall risk and the most influential factor is the fall history of the previous year. In this research, we constructed fall history estimation algorithm by a plantar pressure waveform model during walking. We implemented algorithms based on Feed Forward Neural Network, Support Vector Machine, Auto Encoder, and Principal Component Analysis We carried out the comparison of the algorithms based on the performances of fall history estimation by plantar pressure. The results showed that the reconstructed waveform by Auto Encoder has the best performance. The fall history estimation algorithm that we have developed is expected to become a better fall risk assessment tool for elderly people.

THz optical elements, typically made of silicon (Si), suffer from large reflection due to the large gap in refractive index at the interface between Si and air. In this research, anti-reflection (AR) coating for THz region using polymer and Si nanoparticle (SiNP) composite was developed to minimize the reflection loss. Low absorbance and small diameter of SiNPs allowed the THz waves to transmit the composite without absorption and scattering. The AR layer coated on a THz optical element successfully demonstrated transmittance exceeding 90 % in amplitude as wide as Δf= 0.8 THz 1 THz.

As manufacturing and servicing operations have been increasingly becoming complicated, scheduling which directly effects the manufacturing cost, production quality, level of services is becoming more challenging. By far, various scheduling methods have been developed in order to support decision making in scheduling. It is noted that, however, when a well-tuned scheduling method is applied to different circumstances where scheduling preference of decision makers may be different laborious parameter tuning of the method is required. Such parameter tuning to some extent limits applicability of the scheduling method. To eliminate parameter tuning of scheduling methods, in this study, we proposed a scheduling optimization method with the hybrid objective function. By using small-scale historical schedules evaluated by decision makers, a learning-based objective function is trained to evaluate new schedules. Moreover, to restrain the evaluation errors of the learning-based method which may be caused by the imbalanced training data, the priori objective function is exploited and integrated into the learning-based objective function. The proposed method is validated by a classical scheduling problem, the flow shop scheduling problem with two machines and multiple objectives. Validation results show that, the method outperforms the methods with individual priori objective and learning-based functions. Therefore, by using small-scale evaluation result, the proposed method can capture preference changes of decision makers and avoid laborious parameter tuning of the optimization method.

A large number of ground coils are used in superconducting magnetic levitation (Maglev) systems; therefore, it has been considered that condition monitoring systems for the ground coils are mounted on Maglev trains. We have been studying radio sensing techniques to detect partial discharges (PD) occurring in propulsion coils. In this study, a radio interferometer system with a vector-antenna was mounted on a test bogie, which can be run at the speed of 200 km/h by remote control. The vector-antenna composed of vertical and horizontal dipole-antennas was set to the center of the antenna-array of the radio interferometer system. A set of mock-ups of the propulsion coil and the levitation-guidance coil was set on the side of the test track of which length is 500 m. The propulsion coil has multiple holes penetrating through insulation to the inner conductor for attaching a needle-electrode; one or some of the holes can be voluntarily chosen to generate PDs. Experimental results showed that the propulsion coil with a PD source set behind the levitation-guidance coil could be located from the test bogie running at the speeds of 198.5 km/h and 212.3 km/h.

Currently, there are two coding trends in mobile image sensors: Quad Bayer coding (QBC) and dual photodiode (DPD). QBC realizes high resolution and high dynamic range (HDR), whereas DPD achieves high phase detection auto focus (PDAF) performance. We propose a QBC with 2×2 on-chip lens (2×2OCL) architecture as a potential next-generation high-performance CMOS image sensor. This combines high resolution, HDR, and high PDAF performance in one sensor. The critical issues of 2×2OCL are degradation of the resolution due to the sensitivity difference between 4 pixels under the same color filter and increasing the crosstalk among different colors. To overcome these issues, the OCL and pixel isolation shapes were optimized respectively. The world`s first image sensor using 2×2OCL architecture we prepared in this paper, has 1/2 inch 48M pixels with 0.8µm QBC for high resolution, and all pixel PDAF achieved a minimum AF illuminance level of 1 lux.

For the art appreciation in museums, usually a certain information will be provided as a caption. Visitors usually read the description to help his/her understanding. Museums usually prepare such descriptions for general visitors (viewers). The problem for reading these captions is visitors will not see the artworks after reading the descriptions to understand the art works. However, recently several museums have removed or hidden such descriptions as captions. For instance, the exhibition “Bacon and Caravaggio” held in Museo e Galleria Borghese, Roma did not provide any descriptions as captions. Accordingly visitors can see and think the artworks deeply. This might be a positive aspect of the display strategy. Thus experts show greater flexibility and differentiation in art appreciation. Non-experts will not show flexibility and differentiation in art appreciation. This is a problem in art appreciation. We have conducted several experiments where various types of information offering strategies were performed. From the results, we obtained interesting phenomenon. The participants seemed to be able to gradually understand the artwork by offering information of the artwork. Of course for an abstract art, the information of the artworks functions better understanding of artworks. Even for a representational painting, the level of understanding was gradually changing. Thus the information of art sometimes influences the art appreciation. However, a price will not be related to aesthetics. For the price, it is a rather vulgar matter. However, such a price can be an influential factor in art appreciation and sense of values. In this paper, we will discuss how will the value of art change according to offered information? For that we conducted an experiment. Where information of the artwork was offered randomly. Information involved title, painting materials, production year, name of artist, price, and theme of the artwork.

We have been studying radio sensing techniques to detect partial discharges (PDs) occurring in propulsion coils used in superconducting magnetic levitation (Maglev) systems. In this study, preliminary experiments were carried out for setting an objective of detecting PDs occurring in the propulsion coils by using a radio interferometer system with a vector-antenna mounted on a test bogie, which can be run at the speed of 200 km/h by remote control. In the experiments, the radio interferometer system with the vector-antenna was mounted on the test bogie that was kept stopped; PD sources occurring in a propulsion coil were located. The vector-antenna composed of vertical and horizontal dipole-antennas was set to the center of the antenna-array of the on-board radio interferometer system. An antenna-module contains the antenna-array composed of three dipole-antennas and the vector-antenna. Three sets of mock-ups of the propulsion coil and the levitation-guidance coil were arranged in a row on the side of the test bogie. One of the propulsion coils has eight cylinder-shaped holes penetrating through the insulating material to the inner conductor for attaching a needle-electrode; one or some of the holes can be voluntarily chosen to generate PDs. Experimental results show that a PD source generated at a voluntary position of the propulsion coil could be roughly located by using the antenna-array; the vertical and horizontal components (electric fields) of electromagnetic (EM) waves emitted from the PD source could be separately received by using the vector-antenna.

A super-junction (SJ) device has been developed to improve the trade-off relationship between the breakdown voltage ( $V_{\text{BD}}$ ) and specific on-resistance ( $\boldsymbol{R}_{\mathbf{onA}}$ ). A multi-epitaxial (ME) growth method had been used for fundamental demonstrations, but this method needs a lot of repetitions of epitaxial growth and implantation in the case of SiC material. A trench-filling epitaxial (TFE) growth method is expected as a promising alternative, especially for high-voltage devices. In this study, we have established critical fabrication processes for a thick ( $> 20\ \boldsymbol{\mu} \mathbf{m}$ ) and high-aspect-ratio SJ structure. The measured $\boldsymbol{R}_{\mathbf{onA}}$ of a 7.8 kV SJ MOSFET was $17.8\ \mathbf{m}\mathbf{\Omega}\cdot \mathbf{cm}^{2}$ , which is less than half the $\boldsymbol{R}_{\mathbf{onA}}$ of the state-of-the-art 6.5 kV-class SiC MOSFET with an n-type drift layer. Improvement of trade-off relationship exceeding the 4H-SiC theoretical limit was experimentally demonstrated for the first time.

This paper proposes techniques of automatically discovering tips Web sites from a large collection of Web pages using a topic model and support vector machine (SVM). Tips refer to practical knowledge or expertise that is used to help accomplish certain tasks in a particular field. We designed several approaches of extracting features with respect to domain names based on their distribution among Web pages and candidate tips Web sites. In addition, search engine suggests, the query keywords used to fetch Web pages from the search engine are also considered to present patterns that can be potential features. It was discovered from our dataset that domain names of tips Web sites (Web sites containing tips on a certain specific theme) are more likely dispersed among topics and Web pages. These domain names also tend to correspond to a larger number of search engine suggests. This paper verifies such observed patterns by training an SVM using those extracted features. Evaluation is performed in precision and recall to measure correctness of classifying whether or not a domain name belongs to a tips Web site.

Complex-refractive indices and the optical axis direction in a birefringent material were simultaneously measured. This technique consists of two parts: first, alternate emission of two kinds of polarized THz pulses, generated by periodic modulation of pump pulses with a Pockels cell; and second, polarization-sensitive THz-time-domain spectroscopy (PS- THz- TDS) that simultaneously measures orthogonal components of the THz electric field. Simultaneous measurement of the electric-field vectors of two THz pulses with different polarization states was realized using an FPGA-based controller. In other words, four temporal waveforms were obtained using a single temporal sweep.

We report novel organic mixed crystals composed of DSTMS and DASC. The THz spectra generated from the mixed crystals showed that absorption around 1 THz was very low compared to that of DAST derivatives. Moreover, the THz spectral range and the intensity were as good as those of DAST. Thus, the mixed crystals could be better suited for generating broadband, high-power THz waves.

Newspapers and other media often describe particular topics over some periods by giving a series of texts that introduces new information and corrects previous information. By analyzing such texts, we can understand how a topic changed over time and how the media treated it. However, analyzing such texts manually is time-consuming. To solve this problem, we propose a method for visualizing texts that describe a topic changing over time. For this purpose, we first generate an event information graph from such texts by using an existing method. Then we transform it into two different graphs. The first graph shows changes in the topic that we obtain by separating the initial graph and comparing the resulting time-dependent graphs. The second graph depicts a summary of the topic that we obtain by extracting high-frequency words from the initial graph. The results of our experiment show that our method can visualize changes and important information described in the texts.

Condition monitoring techniques for ground coils used in superconducting magnetic levitation (Maglev) systems are required. In this study, an on-board radio interferometer system with a vector-antenna was developed to locate partial discharge (PD) sources occurring in propulsion coils of superconducting Maglev systems and to know the propagation characteristics of electromagnetic (EM) waves emitted from PD sources. PD current generally develops into multiple directions, that is, the EM waves emitted from the PD current have also multidirectional components. The structures and the arrangement of propulsion coils and levitation-guidance coils might influence the propagation of EM waves. The vector-antenna composed of vertical and horizontal dipole-antennas was set to the center of the antenna-array of the on-board radio interferometer system. Three sets of mock-ups of the propulsion coil and the levitation-guidance coil were also developed in order to evaluate easily the on-board radio interferometer system. One of the propulsion coils has eight cylinder-shaped holes penetrating through the insulating material to the inner conductor for attaching a cap with a needle-electrode; one or some of the holes can be voluntarily chosen. PD current was generated in an air-gap between the tip of the needle-electrode and the surface of the inner conductor. Experimental results show that a PD source generated at a voluntary position of the propulsion coil could be located by using the on-board radio interferometer system; the vertical and horizontal components (electric fields) of the EM waves emitted from the PD source could be separately received by using the vector-antenna.

In order to evaluate the insulation condition of gas insulated switchgear (GIS) by using the ultra-high frequency (UHF) method, attempt to estimate PD current using the finite difference time domain (FDTD) method was carried out. The influence of PD current parameters and the position of measuring point on the received electromagnetic (EM) waves was studied. The EM waves received by using UHF sensors were also simulated by applying a band pass filter to the received signals. Results showed that peak-to-peak value of electric field strength of EM waves was closely related to the peak value and rise time of PD current. The relationship between the peak-to-peak value of electric field strength and the position of measuring point was investigated and the estimation procedure of PD current was proposed.

The two-stage-type electrostatic precipitator has been used for limited applications. It is required to have a compact size and relatively large flow rate. The two-stage-type electrostatic precipitator consists of a pre-charger and a collecting unit. The grounded electrode length in the pre-charger is generally designed to be short. In our previous studies, regarding the influence of the grounded electrode length in the pre-charger on the collection efficiency, it has been considered that the particle charge through the pre-charger decreased for a very short or very long grounded electrode length in the precharger. And therefore, the electric field and space charge distribution were calculated for various grounded electrodes length using a finite-element method. In the case of a very short grounded electrode, the electric field intensity around the high voltage wire electrode decreased. Additionally, the electric field intensity distribution at proximity to the grounded electrode has two additional peaks due to the effect of the edges of the grounded electrode. For the very long grounded electrode, the space charge distribution and the peak of the electric field intensity distribution did not overlap. These results show that there is a suitable length for the grounded electrode of the pre-charger for particle charging.

Superconducting magnetic levitation (Maglev) systems require a large number of ground coils: propulsion coils and levitation-guidance coils, therefore how to monitor the condition of ground coils is a big issue for the real operation. In our previous papers, it is shown that an on-board radio interferometer system is effective for detecting and locating a partial discharge (PD) source occurring in an abnormal propulsion coil. We mounted the two radio interferometer systems on a test vehicle consisting of a bogie and a car for moving-detection and location of a PD source occurring in an abnormal propulsion coil arranged on the U-shaped guideway of Miyazaki Maglev test track. It is shown that the abnormal propulsion coil could be found by using the on-board radio interferometer system while the test vehicle was driven at the speed of 50km/h.