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Acoustic emission (AE) measurement is a non-destructive testing method that can detect high-frequency elastic waves generated by mechanical events inside an object, and is able to localize the wave source by using multiple sensors. In order to determine the mechanism causing the quench phenomenon in superconducting coil, we applied the AE method to a small ellipse-shaped coil in a training experiment. Six AE sensors were installed on the coil surface before the coil was cooled to 4 K in a vacuum vessel and excited. The current to the coil was controlled to produce a gradual increase until the quench occurred. The entire training experiment ended after over 10 quenches and all AE events that occurred in each training cycle were measured. The location of the AE source inside the coil was calculated from the difference in arrival time between sensors, and the results were plotted on an expansion plan of the coil. High-amplitude AE events appeared in areas assumed to have sufficiently high internal stress to cause concentration of strain energy.

A quench is the transition from a superconducting state to a normal conducting state. Elucidating the mechanism of quenching caused by mechanical disturbances (training quench) requires a detailed understanding of the stress state in the coil during excitation. In this study, we developed a large-scale analysis method that can precisely analyze where strain energy is concentrated and loss energy is generated due to thermal stress and electromagnetic force in superconducting coils by considering the detailed structure of superconducting wires and the wire alignment disorder caused by constraints during winding. The results showed that strain energy in the resin is concentrated in the region of overlap between the strain energy distribution caused by the macroscopic deformation of the coil and the geometrically inhomogeneous region, including the wire transfer zone. Furthermore, comparative verification using acoustic emission measurements to determine damage locations suggests that quench is also concentrated at the transfer zone in the actual coil, thus demonstrating the validity of the analysis. A sub-model of the area around the transfer zone, which was found in the large-scale analysis, was created, and crack propagation analysis was conducted using the phase-field method. Crack propagation in the resin and increased deformation of the wire due to weakening of the supporting rigidity of the wire caused by the crack propagation were observed.

Prognostic health monitoring technologies for power electronic systems assess their performance degradation, load histories, and degrees of fatigue in order to increase maintenance effectiveness, reliability design methods, and equipment availability under conditions of actual use. To improve reliability and reduce downtime, prediction of reliability in terms of thermal fatigue life under field conditions is important, as is the use of load and health monitoring data from the field in cases of performance degradation during use, maintenance, and field failure. The fatigue life of solder joints is also affected by whether the load history waveform is symmetric or asymmetric. In this paper, we propose a novel health monitoring method for thermal fatigue failure corresponding to time-dependent inelastic strain response, such as in asymmetric cycles, by use of a surrogate model obtained by a finite element method-based thermal stress simulation. We applied this method to an insulated-gate bipolar transistor power module capable of monitoring module temperature, electrical performance, and number of revolutions of the cooling fan. With the proposed method, inelastic strain cycles and thermal fatigue life distribution of solder joints could be estimated from their temperature monitoring history. The method was judged to be useful for assessing thermal load histories and estimating thermal fatigue life in prognostic health monitoring.

Objective biomarkers are crucial in the development of personalized medicines, such as Japanese traditional medicine (Kampo). To date, some objective markers to predict the response of Kampo medicines have been reported, but the information is somewhat limited. The aim of this study was to search for objective markers and combinations thereof to estimate the effect of the Japanese traditional medicine daikenchuto (DKT) on colon contraction intensity in guinea pigs. Specifically, the microbiome biomarkers were employed as candidate, using the Fisher ratio and the nearest neighbor classifier for statistical pattern recognition. The combination of the ratio between gut microbes of family Ruminococcaceae/Rikenellaceae, Ruminococcaceae/Paraprevotellaceae, and genus Ruminococcus/unknown genus in family Rikenellaceae of guinea pig gut microbes was found to influence the activity of DKT with 0.8 accuracy for test samples. These findings suggest that statistical pattern recognition can contribute to identifying target markers of multi-target drugs such as Kampo.

The decay lifetime of free neutrons (∼880 s) is an important parameter of the weak interaction and for Big Bang Nucleosynthesis. However, results of measurements currently show discrepancies depending on the method used. As most experiments nowadays employ ultra cold neutrons, we have developed a new cold-beam experiment which we perform at the Japan Proton Accelerator Research Complex. As a special feature, a polarized neutron beam is bunched by a spin flip chopper. A time projection chamber operated with He and CO2gas, including a well-controlled amount of3He, is used for detection of the beta-decays and simultaneous determination of the beam intensity. Using the data between 2014 and 2016, we evaluated our first, preliminary result of the neutron lifetime as 896 ± 10(stat.)−10+14(sys.) s. We plan several upgrades to achieve our precision goal of 1 s.

We constructed population pharmacokinetic (PK) models for the five constituents of daikenchuto (DKT), a traditional Japanese herbal medicine. Data were collected from two randomized PK studies conducted in Japan and the United States. Participants received single oral doses of 2.5 g, 5 g, and 10 g of DKT. The plasma concentrations of five DKT constituents--hydroxy-α-sanshool (HAS), hydroxyl-β-sanshool (HBS), 6-shogaol (6S), 10-shogaol (10S), and ginsenoside Rb1 (GRB1)--were determined by liquid chromatography-tandem mass spectrometry. A total of 1859 samples from 55 participants (US, n = 36; Japanese, n = 19) were included in the analysis. Population PK models of HAS, HBS, 6S, and 10S were best described by a one or two-compartment model with a bolus input. On the other hand, the model of GRB1 was best described by a one-compartment model with nonlinear extravascular input. Among the covariates evaluated, body mass index (BMI) and age were found to influence oral clearance (CL/F) and volume of distribution (Vd/F) for HAS and HBS, respectively. The influence of body weight on CL/F and Vd/F for 6S was demonstrated. Marked differences were observed in mean plasma concentrations of HAS and HBS between Japanese and US participants. However, the simulation results indicated that the difference in plasma concentrations may be attributed to the difference in demographic factors such as BMI, body weight, and age, whereas ethnic difference between the Japanese and US participants was considered minimal.

Two patients presented with malignant hypertension associated with encephalopathy predominantly manifesting as brainstem lesion. T(2)-weighted and fluid-attenuated inversion recovery magnetic resonance (MR) imaging revealed diffuse hyperintense areas in the pons and scattered lesions in the cerebellum, basal ganglia, and cerebral subcortex without parieto-occipital lesions. Diffusion-weighted MR imaging demonstrated these lesions as normal intensity, indicating vasogenic edema. These lesions resolved rapidly once hypertension was controlled. Review of clinical findings for 14 other patients with hypertensive brainstem encephalopathy without parieto-occipital lesions suggested that anterior circulation structures supplied by the carotid artery are frequently involved in such patients.

Two patients presented with malignant hypertension associated with encephalopathy predominantly manifesting as brainstem lesion. T(2)-weighted and fluid-attenuated inversion recovery magnetic resonance (MR) imaging revealed diffuse hyperintense areas in the pons and scattered lesions in the cerebellum, basal ganglia, and cerebral subcortex without parieto-occipital lesions. Diffusion-weighted MR imaging demonstrated these lesions as normal intensity, indicating vasogenic edema. These lesions resolved rapidly once hypertension was controlled. Review of clinical findings for 14 other patients with hypertensive brainstem encephalopathy without parieto-occipital lesions suggested that anterior circulation structures supplied by the carotid artery are frequently involved in such patients.

A food pigment (Monascus yellow) extracted from Monascus fermentations (red yeast rice) has been studied as a novel sensitizing dye for dye-sensitized solar cells (DSCs). The photocurrent action spectrum was in agreement with the absorption spectrum of the dye adsorbed on a nanocrystalline-TiO2 electrode. The DSC fabrication process has been optimized in terms of the rinsing solvent used after dye adsorption and the dye-uptake duration. After optimizing nanocrystalline-TiO2 electrodes and pH conditions, the resulting maximal photovoltaic characteristics were an open-circuit voltage of 0.57 V, a short-circuit current of 6.1 mA cm−2, and a fill factor of 0.66, yielding an energy conversion efficiency of 2.3%.

We studied the effects of alumina content and firing temperature on the electrical properties of alumina substrate. Alumina content was varied within the range 91.5% to 98.8%, and firing temperature, within the range 1, 480°C to 1, 640°C. The higher the firing temperature, the greater become the volume resistivity, Te value, dielectric constant (e), and dielectric loss tangent (tan δ). When the alumina content is increased, the coefficient of electric loss (e×tan δ) which is a representative parameter of substrate properties of high frequency decreases, while the volume resistivity, a representative parameter of substrate insulated properties, and the Te value remain invariable.

In order to explain the interrelationships between the substantive region and formal region in rural society, the author selected Kai Province (now Yamanashi Prefecture) as a typical example for study.First of all, the spatial relations between the hanseison (administrative village) and the mura (natural village) in the Edo era were investigated. At that point, the question was how to identify the mura. The author suggested adopting shinto shrines as an operational analytical measure, because they seem to fulfill the function as the center of the rural community. Consequently, several village types can be found on the basis of shinto shrines. Among these types, the suye mura type is frequent in which there are several muras in the hanseison and such mura are smaller than the hanseison in the size of community and area. This suye mura type was dominant in Tsuru county, Nishigori suji, Higashi-Kawauchiryo of the Yatsushiro county, and Henmi suji of the Koma county in the mountainous region. And by contrast with the suye mura type, the hyojun type, equivalent to the hanseison in the size of the community and area, is distinguished in the central part of Kofu basin. Moreover, when the suye mura type is defined in the stricter sense, it refers to the village type in the mountainous, whereas the village type in the plain area is referred to as the Kemuyama mura type.In order to find out the factors leading to the formation of the large-scale hanseison, the author analyzed the Kita-koma district and Kita-Tsuru district. Generally, hanseison in Kai Province up on the basis of topographical conditions.It is clear through examination of the Kita-Koma district and Kita-Tsuru district that the large-scale hanseison in the Kai Province consist of hamlets. Especially, it seems that the large-scale hanseison in Tsuru district coincide with the Kona-shuraku theory.Second, the subject of the spatial reorganization of the mura was examined. This subject offers a valuable topic in analyzing the interrelationships between rural system and administration in the Meiji era and after. On the whole, the major part of Kai Province did not show any spatial reorganization of the mura. Where it did occur, it was mostly the spatial reorganization of the mura, or its breaking up into two or several smaller muras, which can be found in the Manriki, Kuribara, and Henmi suji. The village types in the Manriki and Henmi sujis changed from the kemuyama mura type to the suye mura type. On the other hand, in the spatial reorganization of the mura, a tendency towards expansion and amalgamation occured in many small-scale hanseison, Yet, the amalgamation of towns and villages that was promoted in the early years of the Meiji era seems to have contributed little to the spatial reorganization of the region concerned. This is because the amalgamation did not include material bases (eg, communal land, forest land, etc, ) in the spatial reorganization of the region.Third, the spatial relations between the hanseison and the mura is explained by investigating the village organization, irrigation system, forest land and religious organization for the shinto shrines in the Kita-Koma district. First of all the Kayagatake villages in the late Edo era show the characteristics of the suye mura type and the mura consists of several hamlet units (kumi) in reality. Entering the modern period, the small-territory groups such as hamlets progressed into the mura units. Whereas the village type of Amari Go in the late Edo era approaches the kemuyama mura type.

We studied the effect of alumina content on the sinterability of alumina substrate in relation to the firing temperature. The surface roughness, sintered density, and bending strength of alumina substrate were improved as the alumina content increased. The optimum firing temperature for alumina substrate was defined as the minimum temperature at which the characteristics of alumina substrate were satisfied all the following conditions, 1) The ratio of water absorption is almost zero. 2) The ratio of the sintering shrinkage is 0 to -0.4% of the maximum sintering shrinkage. 3) The sintering density is above 97% of the maximum sintering density. 4) The average surface roughness is 1.3 times of the minimum surface roughness. 5) The bending strength is above 85% of the maximum bending strength. The optimum firing temperature shifted toward higher-temperature side when the content of alumina increased. Thus, the optimum firing temperature for 1.1μm alumina substrate was 1, 520°C for an alumina content of 91.5% 1, 560°C for 96.4%, and 1, 600°C for 98.8%.

The purpose of this study is to propose a model that could explain traditional rural society from a spatial approach. Furthermore, I think that the traditional rural society should be discussed from the standpoint of the spatial forms or spatial design of the village people. To study the subject the author first of all investigated the structure of spatial forms that are regarded as the arrangement of the constituent elements on the rural space, including the patterns of settlement, arable land and forest land. Moreover, I have clarified the formation of social groups and their role within the rural space. Therefore, objectives of this analysis are (A) to describe the evolution process of the life-space and (B) propose a model to exlain the spatial structure of the traditional rural society. In order to explain the subject, the author deals with a hanseison, Gochoda in Koma-gun of Kai (Yamanashi Prefecture) that is located on the southern side of the Mt. Yatsugatake.The results of this study are summarized as follows:(A) The evolution process of the life-space.(1) The first stage: from the latter Middle Ages until just prior to the Kanbun Era (1661). The homesteads of the period were loosely concentrated or scattered on a ridge of gentle slope. In this stage early pioneer families or head families (nakee), of the consanguineous maki bands were scattered on a ridge. Cultivated lands as productive space were not sufficiently reclaimed and the wasteland still occupied about 20% of the total land area.(2) The second stage: from the Kanbun Era (1661) to the Horeki Era (1751-). Rural population increased markedly and consequently, within a hanseison (administrative village) several hamlets or Weiler emerged. It is assumed that these hamlets would correspond to the consanguineous maki bands, which (organized into a head family with its branch families) were already in existence and organized by this period.Analyzing the distribution of arable lands, it becomes evident that each farmer was given rights to specific arable land, that is to say, a furlong. The domain of the hanseison, Gochoda was demarcated by the Land Survey in 1666 (Kanbun Kenchi). Several hamlets were integrated into a hanseison through the irrigation association.(3) The third stage: from the Horeki Era (1751-) to the last days of the Tokugawa regime. Rural population had already reached the limits of the agricultural productivity of those days. The consanguineous maki bands had been weakened by the end of the Tokugawa Period, while small territorial groups, goningumi, lost their administrative significance but strenghtened their economic or social functions more and more. Dosogin organization, which seemed to fulfill the integral function of the mura (natural village), had gradually been established. Disputes with surrounding hanseisons had broken out by the land reclamation of common land (i. e. communal land, forest land etc.) at the southern side of the Mt. Yatsugatake.(B) Spatial structure of the rural settlemants at the foot of the mountain.At the foot of the mountain, the topographical conditions spread out with ridges of gentle slope alternating between valleys with streams. Generally, hamlets were located on the ridges which were disadvantageous for paddy fields. The population size was affected by historical factors as well as by the extent of ridge. In particular, rural settlements along the main traffic route might have become the center of a hanseison.Arable lands as productive space (i. e. a paddy field, an upland field, etc.) were divided into several furlongs according to the complexity of ridges and especially the uplands were located at the periphery of the hamlets or in places which lacked irrigation water.