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Thermal barrier coating (TBC) is deposited onto the gas turbine blade surface in order to protect the substrate from high-temperature combustion gas. Cracks and delamination of the ceramic coating which come from high heat flux loading are serious problem in TBC. In this study, the rapid thermal cycling device utilizing laser irradiation was developed. It was then investigated how the damage progresses in the ceramic coating exposed to cyclic rapid thermal loading. As a result, a sintering layer was formed in the surface of the ceramic coating, although such phenomenon was not recognized in TBC sample tested by the conventional thermal cycling test using an electric furnace. It was also revealed from the cross-sectional observation that the vertical crack was initiated at the surface of TBC and propagated into sintering layer. Finally, mechanical factors of those damages from finite element analysis using the TBC model including sintering progress was discussed

This paper designs the width of slit-like flux barriers to improve the space harmonic distribution of the air-gap flux density in a slit stator motor. The slit stator motor has slit-like flux barriers at wound teeth of the stator. The stator design can adjust the space harmonic distribution with the slit width. Space harmonic distributions govern torque and losses in motors. For this reason,the dependence of the space harmonic distribution on the slit width should be clarified to design slit stator motors. The dependence is investigated through a theoretical calculation based on a magnetic circuit model and a finite element method analysis. These methods show that a space harmonic producing the drive torque is maximised at a slit width and other dominant detrimental space harmonics are decreased with the increase of the slit width. The improved space harmonic distribution is verified by performing an experiment with a measuring rotor., IET Electric Power Applications, 13(8), pp.1125-1130; 2019

Background Invasive pneumococcal disease (IPD) is defined by the detection of Streptococcus pneumoniae on culture from samples obtained from a normally sterile site. Pneumococcal conjugate vaccines (PCV) have been developed for the prevention of IPD that is caused by highly virulent serotypes. Despite the effective reduction of IPD caused by vaccine serotypes after the introduction of PCV, there has been a rapid increase in the incidence of IPD caused by non-vaccine serotypes, and serotype replacement has become a global issue. Case presentation We report a previously healthy 4-month-old girl presenting with a large subcutaneous abscess caused by S. pneumoniae, identified as non-vaccine serotype 28F. The patient had received routine vaccination, including PCV vaccination. After the incision and drainage of the subcutaneous abscess, the patient was treated with antibiotics. She was discharged on Day 7 of hospitalization without any residual sequelae. Conclusions Subcutaneous abscess is a common pediatric skin and soft tissue infection, whereas pneumococcal subcutaneous abscesses are quite rare. As the pneumococcal serotype 28F caused a subcutaneous abscess, this serotype possibly has a high virulence. The incidence of IPD caused by non-vaccine serotypes, such as 28F, is expected to increase in the future. The consolidation of international data on pneumococcal serotypes is important for the development of novel PCV.

Permanent magnet (PM) machines generally employ rare-earth PMs. The rare-earth PMs increase the manufacturing cost of PM machines due to their high material cost. To reduce the manufacturing cost of PM machines, this paper studies a consequent-pole configuration. Consequent-pole PM machines have poles with magnets and poles composed of iron-cores. The rotor design can adjust the air-gap flux density distribution. This improves the average torque and reduces the volume of PMs simultaneously. In this paper, the rotor of a consequent-pole surface-mounted PM machine is designed to reduce the volume of PMs. The characteristics are investigated for the rotor structure through a theoretical calculation and a finite-element method analysis. These results show that the consequent-pole configuration can reduce the volume of PMs in comparison with a conventional one.

This paper proposes bridged slit-stator motors to eliminate the complexity in the manufacturing process. Slit stator motors increase average torque and operational efficiency in comparison with conventional motors. However, such motors complicate the manufacturing process due to the insertion of slits. In the proposed motors, the slits are bridged to connect core parts of the stator. A magnetic circuit model is created from the current flowing through the stator. The air-gap flux density distribution is theoretically obtained. The effect of the bridges is clarified by theoretically and numerically obtaining the air-gap flux density distribution of the bridged slit-stator motors.

Hydrogenated amorphous carbon (a-C:H) coating exhibits different wear behaviors depending on its counterpart material in boundary lubricated sliding contact. In previous works, tribological behaviors of a-C:H coating were investigated against steel, chromium, and germanium counterpart materials. The specific wear rate of a-C:H coating was found to decrease with the ability of its counterpart material to react with or dissolve carbon. The present study investigated how graphitization of a-C:H coating's top layers and interactions of the counterpart material with carbon influence wear behaviors of a-C:H coating in boundary lubrication. Results show that a-C:H coating shows graphitization of its top layers regardless the counterpart material. Correlation with differences in wear behaviors of the a-C:H coating leads to the conclusion that graphitization will induce high wear of a-C:H coating only when there are also atomic interactions between the DLC coating and its counterpart material.

Objective. Kampo medicine, a traditional Japanese medicine, is widely used in Japan, especially in the field of menopause medicine. However, few studies have shown evidence-based effects. This study aimed to confirm the effects of kamishoyosan on menopausal symptoms with a randomized, placebo-controlled, double-blind clinical trial. Methods. Subjects were randomly allocated to groups that received either kamishoyosan (n = 101) or a placebo resembling kamishoyosan (n = 104). The primary outcomes were the change in the number of hot flashes, depression scores, improvements of anxiety, quality of life (QOL), and menopausal symptoms before and 4 and 8 weeks after initiation of treatment with the study drug. The secondary outcome was drug safety. Results. After 8 weeks, the number of hot flashes decreased after treatment in both groups, but there was no significant difference between the two groups. The changes in SDS scores showed the same results. Moreover, no significant differences were observed between the two groups in assessments with the STAI, SF-36, and JSOG menopausal index. No serious adverse effect was reported. Conclusions. This first placebo-controlled double-blind randomized trial with kamishoyosan demonstrated that it was safe and had some effects on climacteric symptoms, but not significant compared with placebo. Some problems, such as placebo effects, in the study of Kampo therapy for menopausal symptoms, were revealed. This trial is registered with the trial registration number. UMIN 000006042.

Investigations on tribological behaviors of Diamond-like Carbon (DLC) coating against other materials are strongly needed for scientific and industrial purposes. Recently, carbon diffusion has been found to play a key role in the wear of hydrogenated amorphous carbon (a-C:H) DLC coating when it is rubbed against steel counterpart material in boundary lubrication. Chromium has been reported to decrease carbon diffusion due to increase of the activation energy. In this research, we investigated on the effects of carbon diffusion on friction and wear properties of a-C:H coating when rubbed against Cr plating material. Results show that compared to steel counterpart, a-C:H coating exhibits lower friction coefficient, lower wear rate, and lower carbon diffusion rate when rubbed against Cr plating counterpart.

This paper proposes a design method of stator cores to modify the component ratio of space harmonics in the magnetic field due to stator windings for 12-slot 10-pole concentrated winding motors. The method inserts slit-like magnetic flux barriers in stator wound teeth. In fractional-slot concentrated winding motors, the magnetic field due to stator windings includes dominant space harmonics with a specific space harmonic that produces drive torque. These space harmonics give rise to undesirable effects that increase iron loss in cores and eddy-current loss in magnets. For 12-slot 10-pole motors with single-layer windings, the proposed method increases the driving space harmonic and decreases dominant detrimental space harmonics. This modification of the space harmonics leads to torque enhancement and efficiency improvement. The efficacy of the proposed method is determined by deriving the winding factor, estimating magnetic flux distribution and motor performance through a finite element method analysis, and demonstrating the actual motor performance of a prototype., IEEE Transactions on Industry Applications, 54(5), pp.4377-4385; 2018

Hormone replacement therapy (HRT) plays a large part in maintaining and improving the quality of life (QOL) of postmenopausal women. Despite this obvious role, the use of HRT has stagnated in Japan as well as the United States, since the interim report of the HRT trial of Women's Health Initiative study was published in 2002. The Japan Society of Obstetrics and Gynecology and Japan Society for Menopause and Women's Health formulated the Guidelines for Hormone Replacement Therapy in 2009, which was subsequently revised in 2012, with the aim of organizing perceptions about HRT and allowing people to provide or receive HRT with a sense of security. Later on, in light of changes in indications for HRT and attitudes toward its impact on cancer risks, amendments were made again in 2017. With the establishment of the 2017 guidelines, practitioners in Japan are able to address various issues related to HRT with more appropriate judgment. Moreover, the practice of reliable, safe and effective HRT is expected to promote further efforts toward improvement or maintenance of QOL in patients.

In order to control wear and friction in industry, Diamond like carbon (DLC) hard coatings are widely applied in recent years due to their well appreciated mechanical and tribological properties. However, those properties are not yet well understood, as well as behavior of DLC hard coatings when rubbed against other materials. Other researchers reported that DLC hard coatings film show high wear when rubbed against steel counterpart and their durability decrease with the increase of the temperature. In this research, we investigated on friction and wear properties of DLC coatings and the results reveal that carbon diffusion has a key role in the wear and friction behavior of DLC coatings when rubbed against steel.

Sensorless control techniques that do not use a linear scale are desired for applications that require a long-stroke linear synchronous motor (LSM). This paper discusses the development of a stator-magnetless LSM (i.e., no magnet is mounted on the stator of the LSM) for sensorless control that includes a high-speed position estimation algorithm based on the magnetic saturation phenomenon. This paper presents a new structure of a flux-switching LSM that achieves a high saliency ratio using a cutout that results in magnetic saturation in the armature core. The effect of the sub-tooth on reducing the cogging thrust is also discussed. Furthermore, the analytical and experimental characteristics of inductance, thrust, cogging thrust, and sensorless drive control are discussed based on a prototype., IEEE Transactions on Industry Applications, 53(5), pp.4559-4568; 2017

The first piston ring application of a hydrogen-free diamond-like carbon (H-free DLC) coating to a mass-production gasoline engine reduces friction. It is found that the friction reduction effect between the cylinder bore and piston is 18%. When H-free DLC is applied to top ring, friction is over 10% reduced. The effect is larger than H-free DLC applied to oil rings. Because DLC as low friction coating is effective in a thin oil film and there are few oil at a large area near piston Top Dead Center (TDC). The friction reduction effect is enhanced when lower viscosity engine oil is used. In this study, the adhesion strength of H-free DLC coating on piston rings is also improved. It is shown that the relation between the adhesion strength and 2 coating parameters; i.e. providing substrate roughness and coating thickness. Adhesion strength is verified by test results using actual parts considered to piston ring environment by gasoline engine. Piston rings with low friction and high reliability are developed.

Due to the demands of expanding the high efficiency area and controllable torque / speed area, the new concept variable field flux motors have been researched. We also proposed a variable field flux motor with a half-wave rectified brushless self-excitation method. This motor is possible to construct a brushless self-excited by connecting a diode in series with the field winding on the rotor. And it is possible to excite and control the rotor field flux by the stator winding current. This paper describes the influence of the rotor and stator core design on the torque and efficiency characteristic for proposed motor. And the final designed model is shown with motor parameters. Further, the variable field flux characteristics of the designed motor are confirmed by electromagnetic field analysis.

We developed a mixing medical device by attaching Shirasu porous glass Millipore membrane to prepare water-in-oil-in-water (WOW) emulsion in a shorter time to be applied as

Diamond-like carbon (DLC) coatings are designed to work under severe lubrication conditions. Depending on working environment, lubrication condition, and counterpart material, DLC coatings can exhibit crucial variations in their tribological behaviors. In the search of a counterpart material to improve tribological performances of DLC coatings in desired environment, we found out in previous work that carbon diffusion is an important parameter that influences the tribological behaviors of amorphous hydrogenated (a-C:H) coating in boundary lubrication. a-C:H coating exhibits high wear against steel counterpart material that has a high carbon affinity/solubility, while its exhibits lower wear against chromium counterpart material that has lower carbon affinity/solubility than steel. These recent findings imply that consideration of the carbon affinity/solubility when choosing a counterpart material for a-C:H coating in boundary lubrication might be of significant importance to improve tribological performances of a-C:H coating. This research investigates tribological behaviors of a-C:H coating against germanium counterpart material that has extremely low carbon affinity/solubility. Results show that there is no atomic interaction between a-C:H coating and germanium during friction and wear test, followed with a very low wear of a-C:H coating., ファイル公開：2020/06/01

Objective. The KOSMOS study, a multicenter, randomized, double-blind, placebo-controlled trial, investigated the effects and safety of kamishoyosan (TJ-24), a traditional Japanese medicine, in the treatment of climacteric disorder. Methods. Japanese women with climacteric disorder were administered a placebo during a 4-week run-in period, after which they were classified as placebo responders (R group) if their score on the modified Questionnaire for the Assessment of Climacteric Symptoms in Japanese Women (m-QACS) with excitability and irritability as the primary outcome improved by ≥ 3 points and as placebo nonresponders (NR group) otherwise. Members of the NR group were randomly allocated to receive either TJ-24 or placebo. After 12 weeks, their m-QACS scores, anxiety and depression, sleep, and overall quality of life (QOL) were compared. Results. The TJ-24 and placebo arms in the NR group included 20 patients each. The change in the m-QACS scores of members of the NR group for excitability and irritability at 12 weeks versus baseline was –3.1 ± 1.7 in the TJ-24 arm, a significant decrease, but compared with –2.7 ± 2.2 in the placebo arm, no significant difference was between two arms. However, the proportion of participants whose score improved by ≥3 points was significantly higher in the TJ-24 arm. In the subgroup analysis of premenopausal women, the changes in the score for excitability and irritability were significantly larger in the TJ-24 arm. The incidence of adverse drug reactions or adverse events did not differ between the two arms, and no serious events were reported. Conclusion. Although no significant difference was identified for the primary outcome, a significantly higher proportion of patients who received TJ-24 displayed improvement. Its high level of safety and effects on excitability and irritability in premenopausal women suggest that TJ-24 may be a useful treatment.

Objective Pregnancy is an opportunity for women to become aware of their risk of cardiovascular disease (CVD), because physiologic responses to dynamic hemodynamic changes can be observed during pregnancy. Accordingly, we hypothesized that blood pressure levels during pregnancy may be associated with the risk of CVD later in life. Study design We used data from the Iwaki Health Promotion Project and designed a population-based, cross-sectional study. In this study, Maternity Health Record Books were collected from women over 40 years of age in order to obtain reliable data regarding past pregnancies. Of a total of 642 women, 432 were selected according to the study criteria. Main outcome measures The associations between blood pressure levels during pregnancy and major CVD risk factors (hypertension and dyslipidemia) were analyzed retrospectively. Results A 10 mmHg increase in the mean diastolic blood pressure level between gestational weeks 12 and 42 conferred a 1.70- and 1.55-fold increase in the risk of hypertension and dyslipidemia, respectively, in later life. Conclusions Blood pressure levels during pregnancy may be associated with CVD risk and could therefore be a useful predictive marker.

Fractional-slot winding configurations have attracted much attention due to the availability of concentrated windings and low cogging torque in permanent magnet brushless motors. For the design of the winding configurations, many design parameters must be determined. The winding factor provides a useful index for the optimal design. However, no general expressions of the winding factor have been derived for all the winding configurations. This study performs the general formulation of the winding factor for the fractional-slot concentrated windings. The winding factor is redefined for stator windings without any information of the numbers of poles. For given stator windings, the optimal numbers of poles are determined from the obtained winding factors. The design strategy for the winding configurations is validated through a finite element method analysis., IET Electric Power Applications, 10(4), pp.231-239; 2016

We developed a mixing medical device by attaching Shirasu porous glass Millipore membrane to prepare water-in-oil-in-water (WOW) emulsion in a shorter time to be applied as 10B-entrapped WOW emulsion for hepatocellular carcinoma (HCC) treatment. Single-dose toxicity studies by intra-arterial injection of 10BSH-entrapped WOW were performed in rabbits and pig, and no side effects were observed. We hope to proceed to the preclinical and clinical studies for further evaluation of 10B compound as multidisciplinary treatments for HCC.

We proposed a half-wave rectified brushless self-excitation method that generates the field flux on the rotor field winding short-circuited by a diode. And the amplitude of the rotor field flux is controlled from a zero to its maximum by the stator excitation current. This paper discusses the influence of turns ratio of stator and rotor windings on the self-excitation method by analysis results.

Fractional-slot concentrated winding motors generate several dominant space harmonics. The space harmonic distribution is closely associated with the motor performance. A slit stator motor (SSM) has been proposed to improve the space harmonic distribution. The motor decreases iron loss. However, the dependence of loss generation on each space harmonic has not attracted much attention. To clarify the dependence, iron loss of the rotor is decomposed with respect to space harmonics. The composition of the iron loss caused by each space harmonic is compared with iron loss caused by stator winding current. This result clarifies that the iron loss can be evaluated for each space harmonic in the SSM.

In this paper, a consequent pole structure is presented to reduce the volume and number of permanent magnets (PMs) in comparison with a benchmark machine. To reduce the manufacturing cost of PM machines, the volume and number of PMs should be reduced. Magnet torque decreases with the volume of PMs. However, the consequent pole structure can generate reluctance torque. Therefore, the consequent pole structure reduces the volume and number of PMs and maintains the torque production by generating reluctance torque. The consequent pole arrangements are studied through a finite element method analysis.

Hormone replacement therapy (HRT) plays a large part in maintaining and improving the quality of life (QOL) of postmenopausal women. Despite this obvious role, the use of HRT has stagnated in Japan as well as the United States, since the interim report of the HRT trial of Women's Health Initiative study was published in 2002. The Japan Society of Obstetrics and Gynecology and Japan Society for Menopause and Women's Health formulated the Guidelines for Hormone Replacement Therapy in 2009, which was subsequently revised in 2012, with the aim of organizing perceptions about HRT and allowing people to provide or receive HRT with a sense of security. Later on, in light of changes in indications for HRT and attitudes toward its impact on cancer risks, amendments were made again in 2017. With the establishment of the 2017 guidelines, practitioners in Japan are able to address various issues related to HRT with more appropriate judgment. Moreover, the practice of reliable, safe and effective HRT is expected to promote further efforts toward improvement or maintenance of QOL in patients.

A segment type linear switched reluctance motor is proposed for a linear actuator or a liner generator. A flat gap motor and a cylindrical gap motor are designed and their characteristics are compared. The movers have concentrated armature windings. The stators consist of segment cores and aluminum block bodies. The characteristics are calculated using a finite element method analysis. The efficiency of the cylindrical gap motor is larger than the flat gap motor because the armature windings without end windings reduces copper loss.

Linear synchronous motor (LSM) is used in industrial machines for positioning and conveying equipment. A variety of layout lines has been suggested to be highly expected to raise productivity. Flexible layout of the track including curved part is an advantage of the application. For example, the track shaped production lines of circular system is used to reduce the waste time that occurs during return and stop of the carrier including the mover. Furthermore, this paper discusses design considerations and verification results of Linear and Curvilinear Synchronous Motor (LCSM) which is a linear motor driving in a straight part and a curved part. It was confirmed that the ratio of the thrust reduction by FEM analysis and prototype evaluation are mostly the same as the result considering by skew factor. Moreover, Multi Carrier Module (MCM) demonstrated drive of LCSM seamlessly.

Characteristics of a line-start permanent magnet linear synchronous motor are presented. The motor is a surface permanent magnet synchronous motor with aluminum plate. It starts and accelerates as an induction motor and moves as a synchronous motor. Design analysis is performed. Basic characteristics in analysis using a finite element method are shown.

We have proposed a claw pole type half-wave rectified variable field flux motor (CP-HVFM) with special self-excitation method. The claw pole rotor needs the 3D magnetic path core. This paper reports an analysis method with experimental BH and loss data of the iron powder core for FEM. And it shows a designed analysis model and characteristics such as torque, efficiency and loss calculation results.

We have proposed a claw pole type half-wave rectified variable field flux motor (CP-HVFM) with special self-excitation method. This paper reports the experimental results under the load condition and various speed command, and shows the fundamental output characteristics such as the voltage and the current, the efficiency. And we consider the influence of the variable field flux control on the fundamental characteristics.

For development of the bone during adolescence, the increased estrogen plays an important role especially in young women as well as GH/IGF-Ⅰ system. Although primary amenorrhea can be caused by various pathological factors, almost of cases have a dysfunction of estrogen secretory systems. For Turner syndrome, which is well-known disease with primary amenorrhea,it is generally recommended that the estrogen therapy is started at adolescence and gradually increased up to adult dose level. Recently studies about the adequate dose of estrogen and the adequate age of adult dose in Turner syndrome revealed that intervention with adult dose of estrogen is required as soon as possible for gaining better bone mineral. In the point of view for bone fragility at the future, early diagnosis and adequate intervention for primary amenorrhea is important.

SUMMARY This paper presents a method for reducing cogging thrust in permanent-magnet-type linear synchronous motors. A phase shift method and supplement tooth method are proposed. The methods do not affect the original thrust performance of the linear motor, nor do they greatly modify its basic shape. The methods are confirmed through experiments and FEM analysis. This paper also discusses the effect of construction errors on cogging thrust.

SUMMARY In a previous paper, we proposed a novel linear synchronous motor with half-wave-rectified self-excitation. A long-stator-type linear synchronous motor was built and its performance was verified by experiments. This paper presents a new current control method for the linear synchronous motor in order to achieve a wide range of speeds and high-power operations. First, we propose a current control method for high-thrust operation in the constant-thrust region. This operation is realized by using the reluctance thrust resulting from the saliency of the linear synchronous motor. We also propose a control method that maximizes the ratio of the thrust to the voltage; this method can be used to expand the operating range. Wide-range-speed operation can be achieved by applying this new control method along with field-weakening control. The thrust and operating characteristics of the proposed control methods are estimated by performing experiments and coupled electric and magnetic analysis.

Diamond-like carbon (DLC) coatings are amorphous hard carbon films which offer excellent mechanical and tribological properties. Recently, these coatings have been applied to engine and powertrain components in passenger cars, including those under boundary lubricated conditions. Tribological performance of DLC coatings in oil lubricated conditions and their interaction with various lubricant additives are very complex due to the variety of DLC coatings and lubricants. In this study, the effects of oil temperature and additive concentration on the wear and friction performance of non-hydrogenated tetrahedral amorphous carbon (ta-C DLC) coating have been investigated. Tribological tests were conducted using a pin-on-disc tribotester with ta-C DLC coated steel pins sliding against non-coated steel discs. Tribological tests were also carried out between DLC coated pin against germanium disc in base oil for clarification of wear mechanism. The ta-C coating gave very low boundary friction with base oil at 50 °C but the coating experienced limited durability with increased wear rate at higher temperature against steel disc. Organic friction modifier glycerol-mono-oleate was able to preserve low friction behavior of the coating at higher temperature with enhanced durability. The anti-wear additive Zinc Dialkyldithiophosphate (ZnDTP) provided excellent wear protection for the ta-C coating due to the formation of thick pad-like tribofilm on steel counterpart at all temperature ranges but rubbing in ZnDTP additivated oil lead to higher friction coefficient. The results obtained at high temperature show the significant and beneficial influence of oil additives on the wear performance of the coating. Based on the obtained results and analysis, the wear performance of non-hydrogenated DLC was found to have a clear dependence on the concentration of the lubricant additives, test temperature and counter material.

A novel synchronous generator is proposed for wind power generation. The field flux is generated by the half-wave rectified excitation method. The generator does not require slip rings and brushes for field power supply, as well as permanent magnets. In this paper, the excitation method is explained, and then, the basic characteristics are calculated using the finite element method analysis. Furthermore, the generator is designed for increasing the output power and efficiency.