Generally, standard direct torque control (DTC) does not require fine current responses from the current controller because the torque and flux of a DTC-based drive are controlled by a closed-loop system without current loops. It is often difficult for the standard DTC to achieve the desired current regulation and fine harmonic current disturbance suppression performancew. In order to overcome these problems, this paper proposes a new stationary reference frame position sensorless control system based on stator flux linkage estimation, and a new sinusoidal current tracking controller. In this paper, the current control performance of IPMSMs using the proposed sinusoidal current tracking controller is evaluated through numerical simulation and experiments. Finally, using the proposed sinusoidal current tracking controller, the effectiveness of the proposed stationary reference frame position sensorless control system with the stator flux control method is confirmed through experimental results.

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This paper presents the recent status of industry-university cooperative research activities in Japan on the mechatronics of information storage and input/output equipment. There are three research committees for promoting information exchange on technical problems and research topics of head-disk interface in hard disk drives (HDD), flexible media transport and image printing processes which are supported by the Japan Society of Mechanical Engineering (JSME), the Japanese Society of Tribologists (JAST) and the Japan Society of Precision Engineering (JSPE). For hard disk drive technology, the Storage Research Consortium (SRC) is supporting more than 40 research groups in various different universities to perform basic research for future HDD technology. The past and present statuses of these activities are introduced, particularly focusing on HDD and flexible media transport mechanisms.

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抄紙機のドライヤーパートは，プレスパートから湿紙を受け取りドライヤー内を搬送する間に，乾燥を促進させて所定の紙質に仕上げる役目を担っている。湿紙の乾燥は「熱」を有効に且つ効率的に利用することであるが，加えて「風」が必要であることも理解されている。
最新の多筒式抄紙機の抄速は2，000m／minに達しつつあり，カンバスが走行することによって発生する風の流れ，いわゆるカンバス随伴空気流の測定実験を行った。各種のカンバスを試料に用いて随伴流を測定した。実験結果に基づき随伴流に関する観察結果を報告する。

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In household refrigerators, the rotational speed of a reciprocating compressor can be appropriately adjusted according to the temperature inside of the refrigerator. The lower rotational speed reduces the power consumption of the compressor. However, several natural frequencies of the compressor exist in the low rotation region, and besides, the unbalance force arising from the piston motion acts on the internal drive unit. Thereby the vibrations of the compressor are likely to be larger due to the resonance in the low rotation region. In this study, a method for supporting the drive unit inside the shell, which is called “the self-standing support” is newly proposed in order to reduce the vibration of the compressor drastically. In the proposed method, a spherical support element is utilized instead of coil springs to support the drive unit. And the drive unit can maintain a stable self-standing state by acting restoring moment due to the gravity while it is directly placed on the shell. The natural frequencies of the compressor can be greatly reduced by decreasing the support stiffness for the drive unit in comparison with the support method using coil springs. Furthermore, in designing the drive unit, the application point of the exciting force is matched with the center of percussion to the contact point on the spherical support. As a consequence, the periodic restraining force acting on the contact point can be minimized. By these two features, it is possible to considerably reduce the vibration transmission from the drive unit to the shell. In the present study, a simplified model for a reciprocating compressor is treated, and the effectiveness of the self-standing support is investigated analytically and experimentally.

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An unbalanced input voltage three-level inverter can be applied to boost the input voltage by employing energy storage devices, such as the electric double layer capacitor (EDLC), in order to enhance the motor output performance. However, the unbalanced input DC voltage limits the output power and generates particular voltage harmonics. In this paper, the harmonic characteristics, a method to change the power distribution and the limit of the power distribution when the ratio of the DC source voltage to the EDLC voltage is changed are discussed.

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In late years, machine-room-less elevators have become mainstream and the demand for further space saving of elevator system is still increasing. At the same time, from the viewpoint of eco-friendliness, we should consider the resource saving as well. However it is difficult to meet these demands with the conventional "Traction sheave system" due to its limit of traction capability. Under this situation, we have recently completed the development of a revolutionary new drive mechanism "TALON Drive" that saves space and resources. The TALON Drive mechanism moves the elevator cab up and down by pressing the technologically advanced belt against the rope surface. We have already obtained EN81 certificate and put it on the European and Middle Eastern market. Commercialization of TALON in , North America and Asia is in progress now. TALON Drive is to be our global standard product in future.

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In order to reduce the power consumption of the household refrigerator further, it is necessary to control the rotation frequency of a reciprocating compressor as low as possible. However, several natural frequencies of the compressor exist in the low rotation frequency region. Therefore, the resonance occur in the compressor due to the unbalance force arising from the piston motion synchronous with rotation frequency, and then the vibration of the compressor may be transmitted to the refrigerator. In this study, the compressor was set on a steel plate for experiment, and the vibration characteristic of the compressor supported by means of conventional four points support method is examined. Based on the obtained results, the five points support method is newly proposed in order to suppress the vibration transmission. In the proposed method, the compressor is supported by low stiffness support elements at the four corners and a high stiffness support element at the center. Analytical and experimental results confirm that the natural frequencies of the compressor can be reduced by means of the five points support method as compared with the four points support method. From the results of driving experiment, it was also proven that the resonance of the compressor is hardly occurred in the low rotation frequency region, and the vibration transmission from the compressor to the plate can be reduced.

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I have been working and living in Japan for a little over 10 years now. I first came over as a graduate student, to work on SuperKamiokande, then started working at KEK as a JSPS fellow after graduating, and now work in the Accelerator Division at KEK. My experiences have varied much over that time, due to different locations and different types of job, but as I look back on my first ten years in Japan, I think I can say that the experiences have been (almost) all positive.

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Gene drive is a powerful system that can spread a desirable genetic trait into an entire species and/or population of a certain region,bypassing Mendelian rules of inheritance. Recently, one of the genome editing technologies, CRISPR/Cas, has been developed, making it easier to use gene drive in many different organisms. However, gene drive has potential risks that impact genetic diversity when organisms produced by CRISPR/Cas-based Gene Drive Technology (CCGDT) are accidentally released; therefore, a high degree of prudence is required when CCGDT is used.

In Japan, a Working Group on Gene Drive has been established in the Academic Association for Promotion of Genetic Studies (AAPGS), and a Statement on the Handling of Gene Drive was issued to the public including research institute across Japan, after comprehensive and extensive discussions by the working group in order to reduce risks posed by CCGDT. A national-wide survey on CCGDT was implemented. The survey revealed that those in managerial positions including members and secretariats of institutional review boards on recombinant DNA, and biosafety officers are conscious of CCGDT, and efforts to grasp experimental plans involving CCGDT are made by utilizing an application form for recombinant DNA experiment. In contrast, potential risks of CCGDT are not understood by many researchers. All stakeholders need to disseminate potential risks and preventive measures regarding CCGDT to all researchers who may wish to use this technology. Researchers should use CCGDT upon understanding its potential risks and taking necessary measures. This report refers to how safety measures for CRISPR/Cas-based gene drive technology which has potential risks to ecological system has been discussed and results of national-wide questionnaire survey on gene

in based on the poster presentation at the Asian Conference on Safety & Education in Laboratory 2018.

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In the present study, an image correlation method was used to determine the site-dependent strain in the porcine anterior cruciate ligament (ACL). In particular, the strain of the ACL in the femoral and tibial attachment areas was quantified when the eight knees were subjected to a maximum of 50 N anterior tibial load that was applied using a 6-DOF robotic system. The ACL strains in the anterior, central, and posterior bundles of the medial, middle and lateral layers were determined as a function of the applied anterior load. In addition, the surface of the ACL was observed using a light microscope under no loading condition. Results revealed that the strain in the medial layer of the ACL increased gradually and almost linearly with the increase of anterior load in the midsubstance area. In contrast, the strain in the femoral and tibial attachment areas of the medial layer of the ACL increased rapidly at the beginning of anterior loading and gradually thereafter with significant differences in slope of strain-anterior load curve found in the anterior and posterior bundles. The largest strain in response to 50 N of anterior force was found in the tibial attachment area in medial and middle layers, while the maximum strain was found in the femoral attachment area in the lateral layer. Microscopic observation indicated that crimp structure was more clearly observed in the femoral and tibial attachment areas than in the mid-substance. These microstructural features of the ACL were may be attributable to the higher and load-dependent, nonlinear strain observed in the attachment areas. Our study suggested that the strain in the ACL at full extension is site- and load-dependent in a non-linear manner at the femoral and tibial attachment areas.

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This paper proposes a dynamic analysis method of the linear resonance actuator under PWM (Pulse Width Modulation) control employing the 3-D finite element method (FEM). The effectiveness of this method is shown by the comparison with the experimental results. Moreover, the influence of the load on dynamic performances is clarified.

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Having undertaken studies into a lightweight and highly efficient superconducting transformer for rolling stock, we developed a prototype with a primary winding, four secondary windings and a tertiary winding using bismuth (Bi-2223) high temperature superconducting wire. Its primary voltage is 25kV, which is widely adopted as the catenary voltage on the world's high-speed lines. We adopted liquid nitrogen cooling, the weight being 1.71t excluding the refrigerator. The maximum output available to maintain superconductivity is 3.5MVA. This paper describes the transformer details and test results.

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To clarify the relation between the ON-voltage of power semiconductors in the inverter and the magnetic properties such as iron loss and the magnetic hysteresis curves, the PWM shaped voltage with the virtual ON-voltage is realized experimentally by means of an arbitrary function generator and an amplifier excitation. The iron loss and the width of the minor loop increase linearly with the increasing ON-voltage. Therefore, if the inverter made a virtual voltage waveform generated by a low ON-voltage of the power semiconductor, the iron loss would be reduced.

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Pneumatic drive systems have higher power/weight ratio. So, it is easy to make a compact and lightweight robot manipulator. On the other hand, compressibility of air and very large friction, which is caused by mechanical seal, worsen the performance of positioning for a pneumatic drive system. Therefore, our goal of this study is to propose a positioning control scheme for pneumatic drive systems. In the proposed control scheme, full state feedback control and the disturbance compensator, which is composed by a disturbance observer and integral control action, are used in order to eliminate the effects of compressibility and friction. Further more, to eliminate the delay of a pneumatic servo valve, we designed the electric motor-driven servo valve which can respond very quickly. The effectiveness of the proposed control scheme and electric motor-driven servo valves is shown through experiments. As a result, by using out this method, a pneumatic drive system can be positioned at arbitrary point as fast as an electric motor does.

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ドローン用の同期モータでは，集中巻多極多スロット構造と SPMSM（表面磁石同期モータ）構造が一般的である。ドライブ装置も 120 度通電方式が採用されている。一方，一般産業用モータでは，小型化・高効率化が重要課題であることから，極数╱スロット比が 2 対 3 や 4 対 3 のものが多く，ドライブ装置も 180 度通電方式で，特にハイブリッド自動車や電気自動車ではベクトル制御が適用される。本稿では，ドローン用モータが一般産業用モータと異なる構造・駆動方式を採用している必然性を明らかにするとともに，ハルバッハ配列界磁をドローン用モータに適用するとこれらの必然性が消滅し，ドローン用モータ╱ジェネレータの小型化・高効率化が実現できる可能性を論じる。

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It is challenging for drivers to interpret the symbols currently displayed on variable message signs (VMS) used on Japan’s intercity expressways. Most people have expressed the need for symbols that are easy to see and understand. Thus, this study proposes symbols and examines their use on roads and in tests on a driving simulator. The effect of the legibility of complex symbols displayed on VMS at expressway junctions is also discussed.

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In this paper, we propose a boundary structure for improving performances of Single-sided Linear Induction Motors (SLIMs). In such machines, solid-plate conductors and back irons are usually used for secondary stators throughout operating regions. However, to take account of deformation due to thermal expansions, secondary stators are constructed from some sections of limited length. Therefore, a propulsive force characteristic declines when the primary armature crosses the boundary between secondary sections. In this study, by adopting a three-dimensional finite element method, detailed phenomena at the boundary between secondary sections have been clarified from the viewpoint of propulsive force and secondary current distributions. Besides the validity of calculated results is verified by the measured results. Further, to suppress the aggravation of characteristic caused by the secondary structural transition, we connect the secondary sections electrically. Finally, the propulsive force characteristic has been improved in spite of the existence of the boundary.

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本研究は,細胞動態のオンライン計測を目指し,高感度かつ長寿命なマイクロ流体デバイス集積型のマイクログルコースセンサの開発を目的としている．本発表では，開発中の電気化学式マイクロセンサの電極表面への酵素(グルコースオキシダーゼ)固定化方法として,物理吸着法と化学架橋法を比較し基本性能評価を実施したので,これらの検討結果について報告する．

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