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National institutes for Quantum Science and Technology (QST) are the implementing body of ITER project in Japan and takes the lead in fusion DEMO reactor development in Japan. The primary candidate of the breeder blanket for JA DEMO is Water Cooled Ceramic Breeder (WCCB) blanket. ITER-Test Blanket Module (TBM) program is an opportunity for the demonstration of DEMO breeding blanket concept under actual fusion environment. QST has led the development of the WCCB TBM Concept in the program since the signing of the TBM Arrangement in 2014. The preliminary design of test blanket system (TBS) is on-going. Recently, the status of the preliminary design of TBS was assessed between QST and the ITER Organization (IO). So, the status of the latest TBS design and the DEMO relevancy is presented. [ABSTRACT FROM AUTHOR]

We developed a novel artificial line circuit that compensates for the time delay of the transient recovery voltage (TRV) for a short‐line fault (SLF) interruption test and an analysis system that automatically extracts each parameter on the SLF line characteristics from the measured waveform with high precision. This new circuit and system can drastically improve the time efficiency for the adjustment and calculation of the prospective line‐side TRV condition, which is carried out before the main test, as compared to conventional methods. We also investigated the effect of the injection current and current transformer (CT) characteristics on the SLF line characteristics. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

As genetically resistant individuals, the "elite controllers" (ECs) of human immunodeficiency virus infection have been focused on as the keys to developing further functional treatments in medicine. In the livestock production field, identifying the ECs of bovine leukemia virus (BLV) infection in cattle is desired to stop BLV transmission chains on farms. Cattle carrying the bovine leukocyte antigen (BoLA)‐DRB3*009:02 allele (DRB3*009:02) have a strong possibility of being BLV ECs. Most of cattle carrying this allele maintain undetectable BLV proviral loads and do not shed virus even when infected. BLV ECs can act as transmission barriers when placed between uninfected and infected cattle in a barn. To identify cattle carrying DRB3*009:02 in large populations more easily, we developed a pooled testing system. It employs a highly sensitive, specific real‐time PCR assay and TaqMan MGB probes (DRB3*009:02‐TaqMan assay). Using this system, we determined the percentage of DRB3*009:02‐carrying cattle on Kyushu Island, Japan. Our pooled testing system detected cattle carrying the DRB3*009:02 allele from a DNA pool containing one DRB3*009:02‐positive animal and 29 cattle with other alleles. Its capacity is sufficient for herd‐level screening for DRB3*009:02‐carrying cattle. The DRB3*009:02‐TaqMan assay showed high‐discriminative sensitivity and specificity toward DRB3*009:02, making it suitable for identifying DRB3*009:02‐carrying cattle in post‐screening tests on individuals. We determined that the percentage of DRB3*009:02‐carrying cattle in Kyushu Island was 10.56%. With its ease of use and reliable detection, this new method strengthens the laboratory typing for DRB3*009:02‐carrying cattle. Thus, our findings support the use of BLV ECs in the field. [ABSTRACT FROM AUTHOR]

In the present work, multiple non existing model order reduction (MOR) techniques for unstable second‐order form systems (SOSs) are proposed. For unstable SOSs, continuous‐time algebraic Lyapunov equations get unsolvable that halt the reduction process. To avoid this problem, unstable SOS is first decomposed into stable and unstable portions and balanced truncation is applied to the stable part. The obtained reduced order model (ROM) for the stable portion is augmented with the unstable portion to obtain the overall reduced system. It is observed that the second‐order structure in ROM for the first technique gets lost as well as augmented unstable dynamics degrade the ROM performance. To cater to these constraints, two structure‐preserving second‐order balanced truncation techniques for unstable SOSs are proposed in second part. System is first stabilized using the Bernoulli feedback stabilization procedure and then gramians are computed for the stabilized system. Further, gramians are partitioned into position and velocity portions to achieve structure preservation in ROM and balanced truncation is applied. As second technique retains second‐order structure as well as involves stabilized system dynamics, this technique far closely approximates original system behavior. Proposed techniques are tested on multiple systems and results certify the correct development of proposed techniques that can be utilized for MOR applications of unstable SOSs. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Background: MRI scanning has revolutionized the clinical diagnosis of lumbar spinal stenosis (LSS). However, there is currently no consensus as to how best to classify MRI findings which has hampered the development of robust longitudinal epidemiological studies of the condition. We developed and tested an automated system for grading lumbar spine MRI scans for central LSS for use in epidemiological research.Methods: Using MRI scans from the large population-based cohort study (the Wakayama Spine Study), all graded by a spinal surgeon, we trained an automated system to grade central LSS in four gradings of the bone and soft tissue margins: none, mild, moderate, severe. Subsequently, we tested the automated grading against the independent readings of our observer in a test set to investigate reliability and agreement.Results: Complete axial views were available for 4855 lumbar intervertebral levels from 971 participants. The machine used 4365 axial views to learn (training set) and graded the remaining 490 axial views (testing set). The agreement rate for gradings was 65.7% (322/490) and the reliability (Lin's correlation coefficient) was 0.73. In 2.2% of scans (11/490) there was a difference in classification of 2 and in only 0.2% (1/490) was there a difference of 3. When classified into 2 groups as 'severe' vs 'no/mild/moderate'. The agreement rate was 94.1% (461/490) with a kappa of 0.75.Conclusions: This study showed that an automated system can "learn" to grade central LSS with excellent performance against the reference standard. Thus SpineNet offers potential to grade LSS in large-scale epidemiological studies involving a high volume of MRI spine data with a high level of consistency and objectivity. [ABSTRACT FROM AUTHOR]

The study aimed to clarify the life space of older adults who use a day care center, to explore for factors related to life space, and to identify the balance elements related to life space. In a cross-sectional study at a day care center located in Japan, 64 adult day care users were assessed using the Life Space Assessment (LSA), Mini-Balance Evaluation Systems Test (Mini-BESTest), Modified Falls Efficacy Scale (MFES), and Stops Walking When Talking test. A correlation analysis between the LSA score and variables and a stepwise multiple regression analysis with the LSA score as the dependent variable and the sub-items of the Mini-BESTest as explanatory variables were performed. The median LSA score was 45.8 (interquartile range: 34–62.8, range: 16–100) points. The LSA score showed a significant correlation with all the sub-items and total scores of the Mini-BESTest and the MFES. Based on the result of the multiple regression analysis, anticipatory postural adjustments (β = 0.31, p = 0.015) and dynamic gait (β = 0.30, p = 0.019) were incorporated into the model (R2 = 0.28, p < 0.001). The life space of adult day care users is narrow, and the 28.4% variance of life space is explained with anticipatory postural adjustments and dynamic gait. [ABSTRACT FROM AUTHOR]

This article introduces a new method for optimizing the placement of a multiple of D‐Statcoms for voltage sag mitigation in distribution systems. The D‐Statcom's placement is optimally selected not only for improving system voltage sag caused by a single fault event but also for all possible fault events in the system of interest. Therefore, D‐Statcom's placement is optimized in a problem of optimization where the objective function is to minimize the system voltage sag index—SARFIx. D‐Statcom's effectiveness for voltage sag mitigation is modeled based on the method of Thevenin's superimposition for the problem of short‐circuit calculation in distribution systems. This article considers the case of using a multiple of D‐Statcoms with a proposed voltage compensating principle that can be practical for large‐size distribution systems. This article uses the IEEE 33‐buses distribution feeder as the test system for voltage sag simulation and influential parameters to the outcomes of the problem of optimization are considered and discussed. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Toyota Motor Corporation and Honda R&D Co Ltd in Japan have developed a mobile power generation/output system, called 'Moving e', comprising a fuel cell electric bus that can carry a large amount of hydrogen in addition to portable external power output devices and batteries. The partners are starting demonstration testing this month of the system's ability to deliver electricity anytime and anywhere. [ABSTRACT FROM AUTHOR]

Japan-based measurement and analysis solutions company Horiba has announced a strategic collaboration with CRMT, a French pioneer in pollutant emission measurements with specific expertise in the development of alternative energy engines and vehicles. The partners will combine Horiba's measurement and automotive emission test systems with CRMT's 'green' mobility engineering expertise to work on the development of hydrogen-based engines and vehicles. [ABSTRACT FROM AUTHOR]

Safety functions for the clay buffer in a repository for high-level radioactive waste (HLW) are fulfilled if the presence of montmorillonite with high swelling capacity and low permeability is maintained in the long-term. The transformation of montmorillonite to the non-swelling mineral illite is addressed in most safety assessments by using simple semi-empirical kinetic models, but this approach contrasts with all other near-field geochemical modelling activities that employ a full description of thermodynamic and kinetic mineral-fluid processes. The consistency of these two modelling approaches has been studied by simulating the montmorillonite to illite transformation in the marine sediment profile penetrated by the Ocean Drilling Program (ODP) Site 1174, offshore Japan. Illite in mixed-layer smectite-illite increases from 20% at <700 m below seafloor (mbsf) to 89% at 1100 mbsf. Illitization of smectite at Site 1174 using the semi-empirical approach has been shown by previous authors to provide a satisfactory match to the gradual change of illite content with depth, albeit with significant differences between model variants. In comparison, the approach used in the current study was to simulate the mineralogical and fluid chemical evolution of a 'packet' of a typical fluid-saturated sediment using a model involving full kinetic and thermodynamic treatment of mineral dissolution-precipitation reactions, along a temperature-time burial curve defined by published thermal conductivity data for Site 1174. The results of these simulations showed that the onset of illitization at a depth of 700 mbsf could be matched, but that the overall rate of conversion was significantly more rapid than observed, or as modelled by the simple semi-empirical kinetic approach. The onset and rate of illite growth was strongly linked to the rate of transformation of amorphous silica to quartz. Geochemical model simulations therefore err on the side of conservatism, but may produce unrealistic estimates of illitization. This comparison demonstrates that models involving full kinetic and thermodynamic treatment of mineral dissolution-precipitation reactions must be carefully applied to simulate other transformation reactions of montmorillonite relevant to the geological disposal of HLW, such as those arising from the interaction of montmorillonite with iron/steel, cement and/or groundwater. • Smectite to illite is usually addressed by semi-empirical models, contrasting with the use of geochemical simulations. • The consistency of these approaches has been studied by simulating smectite illitization at ODP Site 1174, Japan. • Illitization at Site 1174 using the semi-empirical approach gives a good match to the change of illite with depth. • Geochemical simulations showed the onset of illitization was matched, but the rate of conversion was quicker than observed. • This comparison shows that geochemical models must be carefully applied to simulate transformation reactions of smectite. [ABSTRACT FROM AUTHOR]

After a volcanic eruption, the risk of debris flow increases in the case of volcanic ash deposits on a slope. It is necessary to precisely and rapidly know the thickness of such volcanic ash, to ensure proper evacuation warnings against debris flow after the eruption. Traditionally, in order to know the thickness of volcanic ash, several observers make direct measurements in the field, or consult measurement containers. However such practices are dangerous after eruptions, and the accuracy of the survey results can vary with the observer. Therefore a machine-based measurement technique was considered, and the Automatic Tephra and Rain Gauge was developed in Japan. The instrument has good precision but is costly when deployed at multiple observation points.Therefore, we developed a simple, low-cost ash-fall meter, which demonstrated sufficient precision for economical multipoint observation. The meter is composed of an outer container, a funnel, an inner gauge, a filter, and a camera capable of transmitting image data using the 3G network.In order to test the system, a sample instrument was installed at the Kirishima Volcano from October 2017 to August 2018. We sampled the volcanic ash after an explosive eruption in April 2018, and confirmed that the deposit thickness was 1.5 mm. The thickness value was highly similar to that of another investigation. However the image data transmission was cut off after the collection of volcanic ash, and was not restored. We presume that the communication disorder occurred as a result of volcanic ash entering the camera, due to insufficient sealing of the camera box.In the future, we aim to improve the simple ash-fall meter by making use of the knowledge gained in this study, and test the device at other volcanoes. [ABSTRACT FROM AUTHOR]