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An Improved Extraction Scheme for High-Frequency Injection in the Realization of Effective Sensorless PMSM Control
Full text linkHigh-frequency (HF) injection is a widely used technique for low-speed implementation of position sensorless permanent magnet synchronous motor control. A key component of this technique is the tracking loop control system, which extracts rotor position error and utilizes proportional–integral regulation as a position observer for estimating the rotor position. Generally, this process relies on band-pass filters (BPFs) and low-pass filters (LPFs) to modulate signals in the quadrature current to obtain rotor position error information. However, limitations in filter accuracy and dynamic response lead to prolonged convergence times and timing inconsistencies in the estimation process, which affects real-time motor control performance. To address these issues, this study proposes an exponential moving average (EMA)-based scheme for rotor position error extraction, offering a rapid response under dynamic conditions such as direction reversals, step speed changes, and varying loads. EMA is used to pass the original rotor position information carried by the quadrature current signal, which contains HF components, with a specified smoothing factor. Then, after the synchronous demodulation process, EMA is employed to extract rotor position error information for the position observer to estimate the rotor position. Due to its computational simplicity and fast response in handling dynamic conditions, the proposed method can serve as an alternative to BPF and LPF, which are commonly used for rotor position information extraction, while also reducing computational burden and improving performance. Finally, to demonstrate its feasibility and effectiveness in improving rotor position estimation accuracy, the proposed system is experimentally validated by comparing it with a conventional system.journal articl
An Integrative Method of Detection and Localization of Surrounding Vehicles Using GPS and RGB Camera Device Attachments
Full text linkThis study aims to enhance environmental monitoring in a self-driving bus project within an urban environment. Firstly, as previously mentioned, the positions of vehicles in traffic near the self-driving bus should be synchronized. While some researchers utilize LIDAR, RADAR, and camera technologies for environmental monitoring and mapping, these methods have high data requirements and are particularly challenging to implement in real-time operations. This approach will ensure the identification of vehicles using YOLOv9 and the collection of their coordinates. The Pixel Map Match and Filter method will be used to minimize GPS data errors, and camera data will be combined with GPS data based on GPS data interpolation to determine the factors affecting vehicle interaction space. This paper presents the results of this integration, demonstrating improved accuracy and reliability compared to traditional systems, and proposes a technology that can contribute to the development of self-driving vehicles.journal articl
Fuzzy Sentiment Analysis for Hand Gesture Interpretation in Words Expression
Full text linkThis paper will discuss the interpretation of hand gestures using words with the fuzzy sentiment analysis approach in the tea-tasting experiment. In the experiment, participants were asked to drink tea, give a hand gesture, and choose three words that could interpret the hand gesture. The results show that hand gestures cannot be categorized as fixed sentiment labels, considering the meaning can differ depending on each preference. Generally, traditional sentiment categorizes labels as positive, negative, or neutral, which fails to capture human preferences. Therefore, we propose that the fuzzy sentiment model be used to solve the traditional problem, which provides a more flexible approach. Our findings show that interpreting hand gestures such as positive is not always positive but can be neutral-positive and vice versa. The results show that hand gestures alone are insufficient to determine sentiment; word expression is required to capture sentiment's different and complex aspects.journal articl
Squaraine-Peptide Conjugates as Efficient Reporters of Neutrophil Extracellular Traps-Mediated Chronic Inflammation
Full text linkThe excessive and uncontrolled release of neutrophil extracellular traps (NETs) is increasingly linked to the pathogenesis of various inflammatory diseases, cardiovascular disorders, and cancers. Real-time, non-invasive detection of NETs is crucial for understanding their role in disease progression and developing targeted therapies. Current NETs detection methods often lack the necessary specificity and resolution, particularly in vivo and ex vivo settings. To address this, we have developed novel near-infrared squaraine-peptide conjugates by rational molecular design as reporters of NETosis by targeting the protease activity of neutrophil elastase (NE). These self-quenching, cell-impermeable probes enable the precise real-time detection and imaging of NETs. The Förster resonance energy transfer (FRET)-based probe, Hetero-APA, demonstrated high specificity in detecting NETs in vitro and in vivo, generating strong fluorescence in NETs-rich environments. To overcome the limitations of FRET-based probes for ex vivo imaging, we designed SQ-215-NETP, a non-FRET-based probe that covalently binds to the NE. SQ-215-NETP achieved an unprecedented imaging resolution of 90 nm/pixel in human coronary thrombi, marking the first report of such high resolution with a low molecular weight probe. Additionally, SQ-215-NETP effectively detected NETs by flow cytometry. These results highlight the potential of these probes in NETosis detection, offering promising tools for enhanced diagnostics and therapeutic strategies in managing NET-mediated inflammatory diseases and cancers.journal articl
月面での自動運転に向けた走行可能性推定
Full text link九州工業大学博士（工学）九州⼯業⼤学博⼠学位論⽂ 学位記番号：生工博甲第507号 学位授与年⽉⽇: 令和7年3⽉25⽇令和6年度doctoral thesi
鍼刺激による遠隔部末梢血管拡張のモデリングとその検証
Full text link九州工業大学博士（学術）第1章 はじめに| 第2章 鍼刺激による遠隔部末梢血管拡張モデルの提案| 第3章 鍼刺激直後における交感神経による遠隔部末梢血管拡張| 第4章 鍼刺激によるnNOS, eNOS, iNOSルートでの一酸化窒素（NO）の発生とその血液伝搬の検証| 第5章 総括九州⼯業⼤学博⼠学位論⽂ 学位記番号：生工博甲第513号 学位授与年⽉⽇: 令和7年6⽉30⽇令和7年度doctoral thesi
令和6年能登半島地震における地震・津波の複合外力による地盤構造物の被災
No full text本報告は令和6年（2024年）能登半島地震 災害調査団のうち，「津波・地盤の相互作用」調査部門の調査内容を取りまとめたものである。今回の地震では，能登半島東部および一部の西部地域において津波による甚大な被害が見られたが，本調査グループは地盤工学会の調査団として「地盤の視点」を持って津波の被害調査を行い，防潮堤，防波堤，海岸護岸，閘門，海岸に隣接する道路盛土・法面工等に絞った調査を行った。一方，津波の遡上高や地形と津波高さの関係等，海岸工学分野の調査を最優先としていない。当調査グループの調査は主に珠洲市（一部，輪島）を中心に実施した。以下に調査履歴，図1に主な調査箇所を示す。2024 年1 月8 日：赤崎漁港（志賀町）※先行調査、2024 年2 月14 日：鵜飼漁港，鵜飼川，飯田港（珠洲市）、2024 年5 月14 日：鵜飼漁港，鵜飼川，飯田港，粟津海岸（珠洲市）、2024 年5 月15 日：輪島港，輪島漁港（輪島市）、2024 年10 月14 日：鵜飼川（珠洲市）※9 月21 日の豪雨の影響に関する調査journal articl
コンクリート三面張り堤防におけるドレーン工の効果検証に関する遠心模型実験
Full text linkIn this study, a centrifuge model test was conducted to investigate the infiltration of river water into a concrete-covered levee at high water levels, focusing on the presence or absence of drainage works at the landside slope toe. When a conventional concrete retaining structure was installed at the landside toe, river water infiltrated the levee body and increased the pore water pressure near the toe. Furthermore, replacing the concrete retaining structure with a gabion showed that incorporating a drainage function into the retaining structure helped mitigate the rapid increase in pore water pressure within the levee and prevented drainage failure near the slope toe. These results indicate that the toe drainage works and the gabion retaining structure act as a protective measure, effectively preventing soil erosion and structural deformation of the levee.
本研究では，コンクリート三面張り堤防において高水位作用時の堤体への河川水の浸透について，裏法尻の排水設備の有無に着目した遠心載荷実験を行った。コンクリート三面張り堤防の裏法尻に通常のコンクリート製法留工を設置したケースでは，河川水が堤体内に浸透し裏法尻付近で間隙水圧が上昇した。コンクリート製法留工背面に排水ドレーン工の設置することや，法留工をふとんかごに置き換えることで裏法尻付近での間隙水圧の上昇を抑える効果があることを見出した。また，排水設備として設置した法尻ドレーン工およびふとんかご法留工が裏法尻保護の役割を果たし，堤体土の吸出しや堤体の変状を抑制する効果があることを示した。journal articl
An Adaptive Control Method for a Knee-Joint Prosthetic Leg Toward Dynamic Stability and Gait Optimization
Full text linkThis paper presents a hybrid control strategy that combines Model Predictive Control (MPC) and Linear Quadratic Regulator (LQR) to achieve robust and stable tracking of human knee joint motion. The state-space model of the system is discretized to facilitate real-time implementation. MPC is employed to track the knee joint trajectory during dynamic motion, while the LQR controller is activated at critical points, particularly when the joint angle approaches zero, to stabilize the system and ensure safety.conference pape
Reduction of Jc anisotropy in REBCO coated conductors via bilayer structure of columnar and random pinning centers
No full textTo suppress the anisotropy of the angular dependence of the critical current density Jc(θ) under high-temperature (T ∼ 77 K) and low-magnetic-field (B ≲ 3 T) conditions, where superconducting motor and generator applications are anticipated, we fabricated a bilayer structure comprised of a YBa2Cu3O7−δ (YBCO) thin film containing Y2O3 nano-particles (‘Y-NP’ layer) atop a EuBa2Cu3O7−δ (EuBCO) thin film containing BaHfO3 nano-rods (‘Eu-NR’ layer) deposited on a buffered metallic substrate. By comparing vortex pinning bproperties of the Eu-NR/Y-NP bilayer sample with those of single-layer Eu-NR and Y-NP samples, we found that introduced BaHfO3 nano-rods (BHO NRs) in the Eu-NR layer primarily enhance Jc(θ) near the B ∥ c direction, whereas the Y2O3 nano-particles (YO NPs) improve Jc(θ) near the B ∥ ab direction, where the effect of BHO NRs is less prominent. This complementary effect of BHO NRs (θ ∼ 0deg) and YO NPs (θ ∼ 90deg) successfully reduced the Jc(θ) anisotropy at B [T] ≲ 8−0.375(T [K]−65). Simulations of the Jc(θ) anisotropy factor based on the measured Jc(θ) data suggest that optimizing the volume fraction of Y-NP and Eu-NR layers could further minimize the Jc(θ) anisotropy depending on (T, B) conditions.journal articl