13197 research outputs found
Sort by
ジドウ ソウコウ シャリョウ トウジョウシャ ノ ヨビ ドウサ カンキ オ モクテキ ト シタ エイゾウ セイセイ
Get PDF自動走行時は自分自身で運転しておらず道路状況を注視する機会も減少するため，車両の挙動変化による加速度刺激の予測が行われづらくなり乗り物酔いを発症しやすくなることが懸念されている．本稿では、身体にかかる加速感刺激を低減させることを目的として，車両の挙動変化を前もって搭乗者に知覚させ，予備動作を喚起する映像の生成と提示方法の検討を行った．実験は，加速度に応じて投影面形状を変形させた全方位映像を電動車椅子搭乗者にHMDを用いて提示するという方法で行った。その結果，投影面の変形による提示映像の変換が車両の挙動変化時に感じる加速感や減速感を低減させることが確認された．In automated driving, it is difficult to predict the acceleration stimulus that arises due to the vehicle’s behavior change. It is feared that this may lead to motion sickness. In this paper, to reduce the acceleration stimulus, we examined the video generation and display method to make the passengers in automated vehicles perceive the vehicle’s behavior change in advance and to trigger advance preparation of passengers. The experiment was conducted by displaying an omnidirectional video with the projection surface deformed according to the acceleration to a passenger wearing HMD in an electric wheelchair. As a result, it was confirmed that the deformation reduced the perception of acceleration and deceleration.technical repor
A Machine Speech Chain Approach for Dynamically Adaptive Lombard TTS in Static and Dynamic Noise Environments
No full textRecent end-to-end text-to-speech synthesis (TTS) systems have successfully synthesized high-quality speech. However, TTS speech intelligibility degrades in noisy environments because most of these systems were not designed to handle noisy environments. Several works attempted to address this problem by using offline fine-tuning to adapt their TTS to noisy conditions. Unlike machines, humans never perform offline fine-tuning. Instead, they speak with the Lombard effect in noisy places, where they dynamically adjust their vocal effort to improve the audibility of their speech. This ability is supported by the speech chain mechanism, which involves auditory feedback passing from speech perception to speech production. This paper proposes an alternative approach to TTS in noisy environments that is closer to the human Lombard effect. Specifically, we implement Lombard TTS in a machine speech chain framework to synthesize speech with dynamic adaptation. Our TTS performs adaptation by generating speech utterances based on the auditory feedback that consists of the automatic speech recognition (ASR) loss as the speech intelligibility measure and the speech-to-noise ratio (SNR) prediction as power measurement. Two versions of TTS are investigated: non-incremental TTS with utterance-level feedback and incremental TTS (ITTS) with short-term feedback to reduce the delay without significant performance loss. Furthermore, we evaluate the TTS systems in both static and dynamic noise conditions. Our experimental results show that auditory feedback enhanced the TTS speech intelligibility in noise.journal articl
Inertial Measurement Unit-sensor-based Short Stick Exercise Tracking to Improve Health of Elderly People
No full textShort stick exercises have been attracting attention from the viewpoint of preventing falls and improving the health of elderly people and are generally performed under the guidance of instructors and nursing staff at nursing homes. However, in situations such as the COVID-19 pandemic, where people should refrain from unnecessary outings, it is advisable that individuals perform short stick exercises at home and record their exercise implementation status. In this paper, we propose an inertial measurement unit (IMU)-sensor-based short stick exercise tracking method that can automatically record the types and amounts of exercises performed using a short stick equipped with an IMU sensor. The proposed method extracts time-domain and frequency-domain features from linear acceleration and quaternion time-series data obtained from the IMU sensor and classifies the type of exercise using an inference model based on machine learning algorithms. To evaluate the proposed method, we collected sensor data from 21 young subjects (in their 20s) and 14 elderly subjects (79?95 years old), where the participants performed three sets (10 times per set) of eight basic types of short stick exercises (five types for elderly people). As a result of evaluating the proposed method using this data set, we confirmed that when LightGBM was used as the learning algorithm, it achieved F values of 90.0 and 86.6% for recognizing the type of exercise for young and elderly people, respectively.journal articl
Classification of ischemia from myocardial polar maps in 15O-H2O cardiac perfusion imaging using a convolutional neural network
No full textWe implemented a two-dimensional convolutional neural network (CNN) for classification of polar maps extracted from Carimas (Turku PET Centre, Finland) software used for myocardial perfusion analysis. 138 polar maps from 15O?H2O stress perfusion study in JPEG format from patients classified as ischemic or non-ischemic based on finding obstructive coronary artery disease (CAD) on invasive coronary artery angiography were used. The CNN was evaluated against the clinical interpretation. The classification accuracy was evaluated with: accuracy (ACC), area under the receiver operating characteristic curve (AUC), F1 score (F1S), sensitivity (SEN), specificity (SPE) and precision (PRE). The CNN had a median ACC of 0.8261, AUC of 0.8058, F1S of 0.7647, SEN of 0.6500, SPE of 0.9615 and PRE of 0.9286. In comparison, clinical interpretation had ACC of 0.8696, AUC of 0.8558, F1S of 0.8333, SEN of 0.7500, SPE of 0.9615 and PRE of 0.9375. The CNN classified only 2 cases differently than the clinical interpretation. The clinical interpretation and CNN had similar accuracy in classifying false positives and true negatives. Classification of ischemia is feasible in 15O?H2O stress perfusion imaging using JPEG polar maps alone with a custom CNN and may be useful for the detection of obstructive CAD.journal articl
Fabrication of nanoporous Si composite anodes and their application to all-solid-state lithium-ion batteries
Get PDF奈良先端科学技術大学院大学博士(工学)doctoral thesi
Fabrication of micro-ring cavities with perovskites and their lasing characterization
Get PDF奈良先端科学技術大学院大学博士(工学)doctoral thesi
セルフ クスグリ ドウサ ニ オケル ショッカク シカク シゲキ ノ テイジ イチ ト タイミング ガ クスグリ チカク ニ アタエル エイキョウ
Get PDF奈良先端科学技術大学院大学修士(工学)master thesi
