In recent years, there is increasing attention on digitalisation and digitalised society with concepts such as Industry 4.0 and cyber-physical systems (CPS) on the rise. In order to realise this, sophisticated systems using numerous sensors that collect, process, and transmit all sorts of physical data at a large scale and in real-time are necessary. One of those important physical data is temperature. Conventional sensors such as thermocouples and thermal cameras have points of concern regarding energy consumption and calibration. Here, an energy harvesting temperature sensor using magnetic phase transition that has the potential to overcome these challenges is proposed. The proposed device utilises the temperature dependency of the magnetisation and electromagnetic induction to measure the probe temperature in the form of electromotive force. Here, a theoretical approach is taken to demonstrate the applicability of the proposed device as an energy harvesting temperature in the CPS frame work. Namely, a theoretical model for the sensing scheme of the proposed device is formulated to demonstrate how the input parameter of temperature can be outputted as electromotive force.

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The recent few years of the global pandemic have brought increased attention to the importance of collecting large amounts of data about public health in order to prevent outbreaks. In doing so, energy efficiency becomes a crucial point of concern. From the initial data acquisition to the data storage and communication component of a CPS, maintaining a sensible energy efficiency is of paramount importance for a sustainable society. Energy harvesting, where electricity is made from low-quality energy sources, is promising in this regard. In this research, the authors proposed a novel energy harvesting wireless temperature sensor aimed for body temperature. The authors analysed the applicability of the proposed device for a large-scale body temperature sensor, in terms of its quality as a temperature sensor and its energy harvesting capabilities. Namely, an investigation on the fundamental magnetic properties of the sensor probe material in question and the electromagnetic induction capabilities are conducted.

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Regarding Aichi Tokei Denki' s electromagnetic flow sensor which has such disposable structure that its flow-pass portion in contact with liquid can be replaced easily, the resin molding and the bonding technology to construct two flow-passes in the disposal flow-pass chip with high precision are described. Furthermore, the two flow-passes of the disposal flow-pass chip can measure different fluids in different flow-rates. The electromagnetic flow sensor of disposable structure is able to cope with various applications, as replacement of the disposable flow-pass chip can easily be done by any nurse and engineer, because knowledge of flow measurement is not required for the replacement.

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This paper presents results obtained from analytical and experimental studies to evaluate the characteristics of a vibration-control system that employs a sensor for changes in acceleration (also called jerk). We have developed an original jerk sensor that uses the derivative of acceleration as its control input. We evaluated the characteristics of a vibration-cotrol system which applied this jerk sonsor for direct jerk-feedback control. As a control model, we used a one-degree-of-freedom servo system. Analytical and experimental approaches were compared, and the following became clear: (1) The jerk sensor operated correctly. The gain increased 20 dB per decade and the phase of jerk lead that of acceleration by 90 degrees, as it theoretically must. (2) The analytical calculations for step response agreed well with the experimental results. (3) The possibility concerning the improvement of the speed of response was confirmed.

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矩形波渦電流探傷試験（RECT）では低周波と高周波信号を多数同時に取得できる特長があり、金属厚板の表裏面きずの同時検知などといった応用が期待されている。しかし、低周波信号が高周波信号に比べて得られる信号が小さいという課題があった。そこで，積分回路を使用して高周波信号を抑制し、低周波信号の高感度化を行う方法を提案する。検証として、厚さ12mmのアルミ板の裏面に大きさがΦ3、深さ2mm、4mm、6mmの三種類のドリル穴を設けた試験片でRECTを行い、提案手法により裏面きずを全て検出できるか否か検討を行う。

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電子機器から放射される電磁ノイズ源の特定は困難であり，現存するノイズ評価環境では膨大な時間とコストがかかる．本研究では時間とコストを削減し，簡易的なノイズ源特定が可能な微小コイル開発を目的としている．本研究では同軸プローブを用いてコイルを製作し，VNAに接続して評価する．現在はコイルの巻数変更と製作誤差を検証し，コイルの巻数や形状により受信特性(受信強度・指向性)が変化することが分かっている．今回は5巻きコイルを形状比較による特性変化の評価を行い，コイル巻線に隙間が生じることで大きな特性変化が生じることが分かった．

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経頭蓋磁気刺激(TMS)は，電磁誘導により渦電流を脳内に誘起させることで非侵襲に脳神経を刺激する手法であり，脳機能研究や精神疾患治療の分野に応用されている．
刺激目標への適切なTMSのためには，コイルの位置や大きさなどのコイル条件を最適化する必要がある．しかし脳内の渦電流分布の測定は困難であるため，条件設定は経験則に基づいているのが現状である．
本論文では，最適なコイル条件を求めるためのシミュレーションを行った．人間の解剖学的データに基づいた頭部モデルを作成し，言語野のブローカ野とウェルニッケ野におけるそれぞれの刺激位置，コイルの大きさ，電流の大きさ等のコイル条件の違いによる電流分布の変化を調べた．

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　A new polyurethane foam that has the properties of permanent magnet, a permanent magnet urethane foam elastomer, has been developed. Since the surrounding magnetic field distribution changes because of the change in the internal neodymium particles’ arrangement due to the deformation of the urethane foam elastomer, it is possible to use it for vibration power generation. Since the induced electromotive force depends on the deformation velocity according to Faraday’s law, the permanent magnet urethane foam elastomer can be sued for a velocity sensor. In this study, a permanent magnet polyurethane foam elastomer was placed in a coil and the relationship between the deformation velocity and induced electromotive force under repeated compression deformation was investigated experimentally. The waveform and topology of the deformation velocity and induced electromotive force were generally consistent and it is shown that it is possible to estimate the deformation velocity from the induced electromotive force.

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