論文 - 田村 宏樹
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Gunaratne P.N., Harshana R.L.A., Brian M.R., Amarasinghe Y.W.R., Jayaweera N., Tamura H., Jayawardane M.
ACM International Conference Proceeding Series 289 - 293 2020年9月
記述言語：日本語 掲載種別：研究論文（国際会議プロシーディングス） 出版者・発行元：ACM International Conference Proceeding Series
© 2020 ACM. Dysfunctional Uterine Bleeding (DUB) is a common clinical problem that generally affects 20-30% of women in a society. This paper suggests a novel system for thermal balloon endometrial ablation, which allows the Endometrium to be destroyed, easily and safely with minimal menstrual blood loss and it prevents from having any severe blood loss and further anemic conditions that can occur in the future. It incorporates an innovative design and a multi-sensory feedback system with the purpose of making precise positioning of the ablation device inside the uterus. Further, it ensures a higher cost effectiveness by introducing the modularity into the system by keeping the clinical requirements at priority. A Single Board Computer (SBC) along with a microcontroller based control system were employed in order to control and maintain the required conditions inside the uterus, at their optimum levels while performing the operation. Apart from the commercially accepted set values for ablation related conditions, here the consultant/ caregiver was allowed to make changes based on the actual condition of the patient. Finally, all these assemblies were merged to innovate a single, handheld, wireless device. A numerical analysis was conducted based on the generally accepted conditions, to evaluate the depth of the endometrial tissue destruction on a modeled uterus. Further, the proposed system was tested on hysterectomized uteruses, and the performance of the developed model was validated using the obtained results.
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Shimauchi T., Sakurai K., Tate L., Tamura H.
Electronics (Switzerland) 9 ( 9 ) 1 - 15 2020年9月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Electronics (Switzerland)
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Due to the population aging in Japan, more elderly people are retaining their driver’s licenses and the increase in the number of car accidents by elderly drivers is a social problem. To address this problem, an objective data-based method to evaluate whether elderly drivers can continue driving is needed. In this paper, we propose a car driving evaluation system based on gaze as calculated by eye and head angles. We used an eye tracking device (TalkEye Lite) made by the Takei Scientific Instruments Cooperation. For our image processing technique, we propose a gaze fixation condition using deep learning (YOLOv2-tiny). By using an eye tracking device and the proposed gaze fixation condition, we built a system where drivers could be evaluated during actual car operation. We describe our system in this paper. In order to evaluate our proposed method, we conducted experiments from November 2017 to November 2018 where elderly people were evaluated by our system while driving an actual car. The subjects were 22 general drivers (two were 80–89 years old, four were 70–79 years old, six were 60–69 years old, three were 50–59 years old, five were 40–49 years old and two were 30–39 years old). We compared the subjects’ gaze information with the subjective evaluation by a professional driving instructor. As a result, we confirm that the subjects’ gaze information is related to the subjective evaluation by the instructor.
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Emotional variability analysis based I-vector for speaker verification in under-stress conditions 査読あり
Prasetio B.H., Tamura H., Tanno K.
Electronics (Switzerland) 9 ( 9 ) 1 - 15 2020年9月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Electronics (Switzerland)
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Emotional conditions cause changes in the speech production system. It produces the differences in the acoustical characteristics compared to neutral conditions. The presence of emotion makes the performance of a speaker verification system degrade. In this paper, we propose a speaker modeling that accommodates the presence of emotions on the speech segments by extracting a speaker representation compactly. The speaker model is estimated by following a similar procedure to the i-vector technique, but it considerate the emotional effect as the channel variability component. We named this method as the emotional variability analysis (EVA). EVA represents the emotion subspace separately to the speaker subspace, like the joint factor analysis (JFA) model. The effectiveness of the proposed system is evaluated by comparing it with the standard i-vector system in the speaker verification task of the Speech Under Simulated and Actual Stress (SUSAS) dataset with three different scoring methods. The evaluation focus in terms of the equal error rate (EER). In addition, we also conducted an ablation study for a more comprehensive analysis of the EVA-based i-vector. Based on experiment results, the proposed system outperformed the standard i-vector system and achieved state-of-the-art results in the verification task for the under-stressed speakers.
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高機動畦畔草刈機の開発 査読あり
栗原 英二, 山下 晃平, 西川 純, 林 和信, 戸田 勉, 田村 宏樹, 小林 太一, 日吉 健二
農業食料工学会誌 82 ( 4 ) 400 - 411 2020年7月
記述言語：日本語 掲載種別：研究論文（学術雑誌）
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カメラを用いた豚群追跡の可能性に関する研究
千布流星, 田村宏樹
宮崎大学工学部紀要 2020年7月
記述言語：日本語 掲載種別：研究論文（大学，研究機関等紀要）
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宮崎大学工学部で行った高校生「総合的な探究の時間」の評価と課題
田村宏樹, 森田千尋, 盆子原康博, 荒井昌和, 菅本和寛, 坂本眞人, 石津貴弘
宮崎大学工学部紀要 2020年7月
記述言語：日本語 掲載種別：研究論文（大学，研究機関等紀要）
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Widasari E.R., Tanno K., Tamura H.
Electronics (Switzerland) 9 ( 3 ) 2020年3月
記述言語：日本語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Electronics (Switzerland)
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Sleep disorder is a medical disease of the sleep patterns, which commonly suffered by the elderly. Sleep disorders diagnosis and treatment are considered to be challenging due to a time-consuming and inconvenient process for the patient. Moreover, the use of Polysomnography (PSG) in sleep disorder diagnosis is a high-cost process. Therefore, we propose an efficient classification method of sleep disorder by merely using electrocardiography (ECG) signals to simplify the sleep disorders diagnosis process. Different from many current related studies that applied a five-minute epoch to observe the main frequency band of the ECG signal, we perform a pre-processing technique that suitable for the 30-seconds epoch of the ECG signal. By this simplification, the proposed method has a low computational cost so that suitable to be implemented in an embedded hardware device. Structurally, the proposed method consists of five stages: (1) pre-processing, (2) spectral features extraction, (3) sleep stage detection using the Decision-Tree-Based Support Vector Machine (DTB-SVM), (4) assess the sleep quality features, and (5) sleep disorders classification using ensemble of bagged tree classifiers. We evaluate the effectiveness of the proposed method in the task of classifying the sleep disorders into four classes (insomnia, Sleep-Disordered Breathing (SDB), REM Behavior Disorder (RBD), and healthy subjects) from the 51 patients of the Cyclic Alternating Pattern (CAP) sleep data. Based on experimental results, the proposed method presents 84.01% of sensitivity, 94.17% of specificity, 86.27% of overall accuracy, and 0.70 of Cohen’s kappa. This result indicates that the proposed method able to reliably classify the sleep disorders merely using the 30-seconds epoch ECG in order to address the issue of a multichannel signal such as the PSG.
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The long short-term memory based on i-vector extraction for conversational speech gender identification approach 査読あり
Barlian Henryranu Prasetio,Hiroki Tamura,Koichi Tanno
Artificial Life and Robotics 2020年1月
記述言語：英語 掲載種別：研究論文（学術雑誌）
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KONDO Kenya, TAMURA Hiroki, TANNO Koichi
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences 103 ( 2 ) 486 - 491 2020年
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：一般社団法人 電子情報通信学会
In this paper, we propose the low voltage CMOS current mode reference circuit using self-regulator with adaptive biasing technique. It drastically reduces the line sensitivity (LS) of the output voltage and the power supply voltage dependence of the temperature coefficient (TC). The self-regulator used in the proposed circuit adaptively generates the minimum voltage required the reference core circuit following the PVT (process, voltage and temperature) conditions. It makes possible to improve circuit performances instead of slightly increasing minimum power supply voltage. This proposed circuit has been designed and evaluated by SPICE simulation using TSMC 65nm CMOS process with 3.3V (2.5V over-drive) transistor option. From simulation results, LS is reduced to 0.0065%/V under 0.8V < <i>V<sub>DD</sub></i> < 3.0V. TC is 67.6ppm/°C under the condition that the temperature range is from -40°C to 125°C and <i>V<sub>DD</sub></i> range is from 0.8V to 3.0V. The power supply rejection ratio (PSRR) is less than -80.4dB when <i>V<sub>DD</sub></i> is higher than 0.8V and the noise frequency is 100Hz. According to the simulation results, we could confirm that the performances of the proposed circuit are improved compared with the conventional circuit.
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Sakurai K., Tamura H.
Sensors (Switzerland) 19 ( 21 ) 2019年11月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Sensors (Switzerland)
© 2019 by the authors. Licensee MDPI, Basel, Switzerland. Car operation requires advanced brain function. Currently, evaluation of the motor vehicle driving ability of people with higher brain dysfunction is medically unknown and there are few evaluation criteria. The increase in accidents by elderly drivers is a social problem in Japan, and a method to evaluate whether elderly people can drive a car is needed. Under these circumstances, a system to evaluate brain dysfunction and driving ability of elderly people is needed. Gaze estimation research is a rapidly developing field. In this paper, we propose the gaze calculation method by eye and head angles. We used the eye tracking device (TalkEyeLite) made by Takei Scientific Instruments Cooperation. For our image processing technique, we estimated the head angle using the template matching method. By using the eye tracking device and the head angle estimate, we built a system that can be used during actual on-road car operation. In order to evaluate our proposed method, we tested the system on Japanese drivers during on-road driving evaluations at a driving school. The subjects were one instructor of the car driving school and eight general drivers (three 40–50 years old and five people over 60 years old). We compared the gaze range of the eight general subjects and the instructor. As a result, we confirmed that one male in his 40s and one elderly driver had narrower gaze ranges.
DOI： 10.3390/s19214774
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Semi-supervised deep time-delay embedded clustering for stress speech analysis 査読あり
Prasetio B., Tamura H., Tanno K.
Electronics (Switzerland) 8 ( 11 ) 2019年11月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Electronics (Switzerland)
© 2019 by the authors. Licensee MDPI, Basel, Switzerland. Real stressed speech is affected by various aspects (individual characteristics and environment) so that the stress patterns are diverse and different on each individual. To this end, in our previous work, we performed an unsupervised clustering method that able to self-learning manner by mapping the feature representations of the stress speech and clustering tasks simultaneously, called deep time-delay embedded clustering (DTEC). However, DTEC has not confirmed yet the compatibility between the output class and informational classes. Therefore, we proposed semi-supervised time-delay embedded clustering (SDTEC) as a new framework of semi-supervised in DTEC. SDTEC incorporates the prior information of pairwise constraints in the embedding layer and simultaneously learns the feature representation and the clustering assignments. The prior information was used to guide the clustering procedure so that the points that belong to the incorrect cluster can be corrected. The effectiveness of the proposed SDTEC was evaluated by comparing it with some baseline methods in terms of the clustering error rate (CER). Moreover, to demonstrate SDTEC’s capabilities, we conducted a comprehensive ablation study. Based on experiment results, SDTEC outperformed the baseline methods and achieves state-of-the-art results in semi-supervised clustering.
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Generalized Discriminant Methods for Improved X-Vector Back-end Based Stress Speech Recognition 査読あり
Barlian Henryranu Prasetio,Hiroki Tamura,Koichi Tanno
IEEJ Transactions on Electronics Information and Systems 139 ( 11 ) 1341 - 1347 2019年11月
記述言語：英語 掲載種別：研究論文（学術雑誌）
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A deep time-delay embedded algorithm for unsupervised stress speech clustering 査読あり
Prasetio B., Tamura H., Tanno K.
Conference Proceedings - IEEE International Conference on Systems, Man and Cybernetics 2019-October 1193 - 1198 2019年10月
記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス） 出版者・発行元：Conference Proceedings - IEEE International Conference on Systems, Man and Cybernetics
© 2019 IEEE. In this paper, we introduce a new unsupervised clustering algorithm to categorize the stress speech data, called deep time-delay embedded clustering (DTEC). DTEC consisted of a time-delay neural network (TDNN) based autoencoder and the joint supervision of discriminative loss, reconstruction loss, and clustering loss. The TDNN-based autoencoder was designed to transform a high-dimensional input into its low-dimensional output by supervision of reconstruction loss. The inter-cluster push-force and the intracluster pull-force were optimized by supervision of discriminative loss. The distance between the softmax prediction probability and its auxiliary target distribution was minimized by supervision of clustering loss. Based on our experiments, DTEC outperforms the popular deep clustering algorithm and able to increase the clustering performance in terms of accuracy(ACC) and normalized mutual information (NMI).
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Widasari E., Tanno K., Tamura H.
Conference Proceedings - IEEE International Conference on Systems, Man and Cybernetics 2019-October 1187 - 1192 2019年10月
記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス） 出版者・発行元：Conference Proceedings - IEEE International Conference on Systems, Man and Cybernetics
© 2019 IEEE. Sleep quality has an important role in the health of the human being. There are some risks due to the lack of sleep quality, such as reduced productivity of work, mental, and physical health. Obtrusive sleep apnea (OSA) is a potentially serious sleep disorder. It caused breath repeatedly to stop and start during sleep. Polysomnography (PSG) is the most common approach of sleep quality assessment for OSA patients. However, this method is intrusive and involved a lot of costs. Therefore, this research is proposed to develop an automatic and non-intrusive method of sleep quality assessment for OSA patients. The proposed method used only ECG signal that easy to conduct and record. The HRV spectrum analysis was applied to features extraction and DTB-SVM classifier was used to measure four parameters of sleep quality: Sleep Onset Latency (SOL), Total Sleep Time (TST), Sleep Efficiency (SE), and Delta-Sleep Efficiency (DSE) based on 30-second segments of ECG signals. 25 subjects of OSA patients' database were evaluated in this research. The sleep quality was estimated using automatic sleep stage and then compared with PSG data. Mean absolute errors in SOL, TST, SE, and DSE are 0.6 minutes, 9.6 minutes, 2.26%, 0.85%, respectively. This results implied that the proposed method could be reliably for applied sleep quality assessment in-home and portable system instead of using a multichannel signal for OSA patients.
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Method for estimating locomotive syndrome based on walking motion 査読あり
田村 宏樹，鶴田 来美，帖佐 悦男
臨床バイオメカニクス学会誌 40 223 - 229 2019年8月
記述言語：英語 掲載種別：研究論文（学術雑誌）
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A New Investigation of Automatic Sleep Stage Detection using Decision-Tree-Based Support Vector Machine and Spectral Features Extraction of ECG Signal 査読あり
Edita Rosana Widasari, Koichi Tanno, Hiroki Tamura
IEEJ Transactions on Electronics Information and Systems 139 ( 7 ) 820 - 827 2019年7月
記述言語：英語 掲載種別：研究論文（学術雑誌）
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Widasari E., Tanno K., Tamura H.
IEEJ Transactions on Electronics, Information and Systems 139 ( 7 ) 820 - 827 2019年7月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：IEEJ Transactions on Electronics, Information and Systems
© 2019 The Institute of Electrical Engineers of Japan. This research is proposed to investigate an easy, fast, and effective method for automatic sleep stage detection using spectral features extraction from electrocardiography (ECG) signal alone. Sleep stage detection is the gold standard for sleep analysis. A sleep physician may suspect a treatment and diagnosis of sleep diseases through sleep stage detection. Polysomnography (PSG) method that generally used for detecting sleep stage. This method is intrusive and difficult to be implemented for in-home and portable systems. Moreover, it is involved a lot of effort, time and cost. The automatic sleep stage detection that uses only ECG signal is expected can solve these problems. The proposed method was tested and evaluated on 51 subjects that consist of 16 healthy subjects, 9 patients with insomnia, 4 patients with sleep-disordered breathing, and 22 patients with REM behavior disorder. In this research also tried to apply a minimal feature for automatic sleep stage detection. The two features applied were the normalized Low Frequency, LF (n.u.) band power and normalized High Frequency, HF (n.u.) band power that obtained from spectral features extraction. These features were then used as inputs for sleep stage classification. Mostly commonly used learning classifiers is implemented to classify sleep stage, namely KNN, NN, DT, SVM, and proposed DTB-SVM. The proposed method using DTB-SVM and spectral features extraction of ECG achieved an average classification specificity, sensitivity, and overall accuracy of 98.31%, 91.84%, 95.06%, respectively. The proposed method is able to obtain all sleep stage condition on patients and non-patients subjects. However, it is feasible to implement in-home and portable system of automatic sleep stage detection instead of using a multichannel signal.
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A STUDY ON MULTIPLE PIGS TRACKING USING OBJECT TRACKING METHOD WITH LEARNING FUNCTION 査読あり
Ryusei Chibu, Hiroki Tamura, Koichi Tanno
Proc. of 2019 International Conference on Machine Learning and Cybernetics, July 2019. 2019年7月
記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
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A STUDY ON EYE MOVEMENT MEASUREMENT METHODS FOR COMMUNICATION 査読あり
Taro Yamanoue, Hiroki Tamura, Koichi Tanno
Proc. of 2019 International Conference on Machine Learning and Cybernetics, July 2019. 2019年7月
記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
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A STUDY ON RELATIONSHIP BETWEEN THE GAZE INFORMATION NEAR TRAFFIC SIGNAL AND THE DRIVING OPERATION 査読あり
TAKUMI SHIMAUCHI, HIROKI TAMURA, KOICHI TANNO, YUKIO HATTORI
2019 International Conference on Machine Learning and Cybernetics 2019年7月
記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）