著者
Tomohiro Murase Kosuke Oiwa Akio Nozawa
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌C(電子・情報・システム部門誌) (ISSN:03854221)
巻号頁・発行日
vol.138, no.9, pp.1148-1153, 2018-09-01 (Released:2018-09-01)
参考文献数
22
被引用文献数
4

In automated driving at Level 3, drivers constantly need to allocate attention to the driving environment to react immediately to a take-over request. However, the amount of attention of drivers to the driving environment has not been quantified. The objective of this study was a quantitative evaluation of the amount of attention to the driving environment, and the psychophysiological state of the driver, during automated driving at Level 3. Attention and driver state at Level 3 were evaluated using ERP and psychophysiological indices respectively with compared to Level 2. The dual task method was used, in which twelve subjects performed driving tasks (Level 2 and Level 3) on a driving simulation system while in parallel performing an auditory oddball task. The data showed that the amount of attention to the driving environment at Level 3 decreased in comparison to Level 2, as indirectly measured by a 19.2% increase in attention to the auditory oddball task. Sympathetic nervous system activity during Level 3 automated driving decreased as compared to Level 2. In the psychological state, comfortable feeling and arousal level decreased at Level 3.
著者
Genki Kato Kosuke Oiwa Tatsuya Iwaki Tomoharu Ishikawa Akio Nozawa
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌C(電子・情報・システム部門誌) (ISSN:03854221)
巻号頁・発行日
vol.138, no.7, pp.805-811, 2018-07-01 (Released:2018-07-01)
参考文献数
20
被引用文献数
1

Selfies may have an effect on the psychophysiological state. The objective of the present study was to evaluate the psychophysiological state by providing feedback for selfies. The effect of the time period was also investigated. The period from the date a selfie was taken to the experiment date was configured as 2 conditions: a Short period (1-40 days) and a Long period (41-80 days). In this study, the evocation of emotions was attempted by providing feedback for four types of selfie 1: good face, 2: bad face, 3: good psychological state, and 4: bad psychological state. “Comfort emotion”, “Like emotion”, and “Awareness” significantly increased when providing feedback for a selfie evaluated as having a good face and a good psychological state. The experimental results using two-way analysis of variance revealed that the physiological state was not affected by the time period, but the psychological state was affected by the time period. The combination of (Positive Face Evaluation) × (Long period) selfies had more positive effect on “Awareness”.
著者
Hiroki Ito Shizuka Bando Kosuke Oiwa Akio Nozawa
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌C(電子・情報・システム部門誌) (ISSN:03854221)
巻号頁・発行日
vol.138, no.7, pp.812-821, 2018-07-01 (Released:2018-07-01)
参考文献数
39
被引用文献数
1

An imbalance of the circadian rhythm due to an irregular lifestyle leads to autonomic dystonia. The long-hour variations of the physiological indices such as core temperature and heart rate variability, associated with the autonomic nervous activity, have been focused. Additionally, the relationships between these physiological indices and facial skin temperature have been reported. The objective of this study is to identify the day-long variable components of facial thermal images (FTIs) to evaluate the corresponding variations of autonomic nervous activity by non-contact measurement. In this study, the measured FTIs were subjected to independent component analysis (ICA). Additionally, multiple regression analysis was performed to estimate the relationships between independent components, extracted from FTIs, and other psychophysiological indices, associated with autonomic nervous activity. As a result, the facial day-long variable components, representing the reproducible rhythm through multiple days, were identified by applying ICA to several different combinations of FTIs. Moreover, these components were associated with the axillary temperature. Therefore, the long-period variations, associated with autonomic nervous activity, could be evaluated from the facial skin temperature.
著者
Kosuke Oiwa Shizuka Bando Akio Nozawa
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌C(電子・情報・システム部門誌) (ISSN:03854221)
巻号頁・発行日
vol.138, no.7, pp.783-789, 2018-07-01 (Released:2018-07-01)
参考文献数
36

Hypertension is one of the leading risk factors for cerebrovascular, cardiovascular, and chronic kidney diseases. Regular measurement and monitoring of blood pressure is important to decrease or prevent pathogenesis of diseases. Contactless measurement of blood pressure using a smartphone application, can enable regular monitoring. The objective of this study is to construct a system which can monitor blood pressure anytime and anywhere. In this study, contactless blood pressure assessment was attempted, using facial visible image analysis and created individual models for blood pressure estimation. Variation in brightness of the skin color was obtained from facial visible images and applied to independent component analysis, which is one of the blind source separation methods to extract the facial photoplethysmogram (PPG) component using a proposed system. Amplitude and phase of facial PPG component were used as indices for blood pressure. A correlation analysis between facial PPG component and blood pressure was performed and created individual models for blood pressure estimation.
著者
Yusuke Ozawa Kosuke Oiwa Shunsuke Miyazaki Seiya Nishimura Yasushi Nanai Akio Nozawa
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌C(電子・情報・システム部門誌) (ISSN:03854221)
巻号頁・発行日
vol.140, no.7, pp.769-774, 2020-07-01 (Released:2020-07-01)
参考文献数
19
被引用文献数
4

Long-term and continuous vital sign monitoring is essential for the early detection of hypertension. Blood pressure sensing based on non-contact biological measurement indices such as photoplethysmograms and skin temperature that can be obtained using visible light and infrared images has been attempted in previous studies. Near-infrared light has high transmissivity to living tissues and has been used for measuring arterial oxygen saturation. This study aims to improve the accuracy of non-contact blood pressure sensing using near-infrared light.
著者
Ayaka Masaki Kent Nagumo Kosuke Oiwa Akio Nozawa
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌C(電子・情報・システム部門誌) (ISSN:03854221)
巻号頁・発行日
vol.140, no.3, pp.409-410, 2020-03-01 (Released:2020-03-01)
参考文献数
3

A large number of traffic fatalities are caused by falling asleep at the wheel. Several drowsiness detection technologies have been developed in recent years. A previous study describes how hemodynamics can vary significantly due to drowsiness. However, it was difficult to estimate drowsiness from the time series of hemodynamics. In this study, general models for estimating three drowsiness levels (i.e., high, medium, and low) based on hemodynamics were constructed using a convolutional neural network for detecting the condition before a state of complete sleepiness is reached, the goal being traffic accident prevention. The results showed that the accuracy of the model was 68.9%.
著者
Rikito Okamoto Shizuka Bando Akio Nozawa
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌C(電子・情報・システム部門誌) (ISSN:03854221)
巻号頁・発行日
vol.136, no.8, pp.1142-1148, 2016-08-01 (Released:2016-08-01)
参考文献数
40
被引用文献数
2

There have been a number of investigations into image recognition and the assessment of human physiological states using infrared thermography. Assessing a human's physiological state by infrared thermography typically exploits the skin temperature of the nasal region and forehead, whereas other parts of the face are less frequently used. The present study has developed a method of analyzing facial thermal images (FTIs) by independent component analysis (ICA), a type of blind signal processing (BSP). ICA is a well-known statistical analysis tool that estimates the original source signal from observed mixture signals. When applied to thermal images, ICA is predicted to extract blind signals such as those from other parts of the face. In this study, the authors use ICA to conduct BSP on a series of FTIs. The extracted independent components are shown to represent temperature fluctuations from the opening and closing of the eyes, respiration, truncal sites such as the cheeks and forehead, and possibility of sympathetic nervous system activity. The FTIs reconstructed after the removal of artifacts indicate the local features that the blind signal cannot extract from the original FTIs.