自然視条件下脳波計測の精度向上を可能にする眼球運動情報を用いた解析方法に関する研究

As the technique of electroencephalogram (EEG) developed for such many years, its application spreads and permeates into different areas, such like, clinical diagnosis, brain-computer interface, mental state estimation, and so on. Recently, using EEG as a tool for estimate people’s mental state and its extensional applications have jump into the limelight. These practical applications are urgently needed because the lack of subjectively estimating methods for the so called metal states, such as the concentration during study, the cognitive workload in driving, the calmness under mental training and so on. On the other hand, the application of EEG signals under daily life conditions especially when eye movements are totally without any constrains under a ‘fully free-view’ condition are obedient to the traditional ocular artifact suppression methods and how it meets the neuroscience standard has not been clearly expounded. This cause the ambiguities of explaining the obtain data and lead to susceptive results from data analysis. In our research, based on the basic idea of employing and extending EEG as the main tool for the estimation to mental state for daily life use, we confirmed the direction sensitivity of ocular artifacts induced by various types of eye movements and showed the most sensitive areas to the influence from it by multi zone-of-view experiment with standard neuroscience-targeted EEG devices. Enlightened from the results, we extended heuristic result on the use of more practical portable EEG devices. Besides, for a more realistic solution of the EEG based mental state estimation which is supposed to be applied for daily life environment, we studied the signal processing techniques of artifact suppression on low density electrode EEG and showed the importance of taking direction/eye position information into account when ocular artifact removal/suppression. In summary, this thesis has helped pave the practical way of using EEG signals toward the general use in daily life which has irregular eye movement patterns. We also pointed out the view-direction sensitivity of ocular artifact which helps the future studies to overcome the difficulties imposed on EEG applications by the free-view EEG tasks.九州工業大学博士学位論文 学位記番号:生工博甲第262号 学位授与年月日:平成28年3月26日1 Introduction|2 EEG measurements and ocular artifacts|3 Regression based solutions to ocular artifact suppression or removal in EEG|4 Measuring EEG with eye-tracking system|5 Direction and viewing area-sensitive influence of EOG artifacts revealed in the EEG topographic pattern analysis|6 Performance improvement of artifact removal with ocular information|7 Summary九州工業大学平成27年

Driver emotion recognition framework based on electrodermal activity measurements during simulated driving conditions

An extensive variety of wellbeing frameworks had been introduced in modern vehicles a decade ago. Traction control, auto-braking, and anti-sleep systems are significant innovations that are presumed to be superior over human reaction. However, accident rates in Malaysia have yet to be fully reduced. In fact, in 2013, nearly one million enlisted vehicles were involved in road accidents, with damages reaching over RM9.3 billion. Meanwhile, a car is a system that encompasses the road, the vehicle, and the driver. At present, roads and vehicles have gained immense stability, but the driver remains as the most fragile component of this system. Electrodermal activity (EDA) was used in this study to investigate stress and anger as primary emotions leading to possible accidents involving the driver. A simulated driving assignment with preset neutral, stress, and anger scenarios was developed for emotional stimulation. A total of 20 subjects were included in this experiment. Acquired EDA signals were bandpass-filtered at 0.5 Hz to 2 Hz and subjected to short-time Fourier transform. Then, their mean, median, and variance of power spectral density were extracted. The parameters obtained were statistically analyzed with two-sample f-test. EDA readings from drivers demonstrated significant differences among neutral-stress, neutral-anger, and stress-anger simulated driving scenarios. The dataset was also divided into two groups (10-10) for training and testing of support vector machine classifier at 10-fold cross-validation. The classification accuracy was 85% each for neutral-stress and neutral-anger and 70% for stress-anger

Methodological Design for Integration of Human EEG Data with Behavioral Analyses into Human-Human/Robot Interactions in a Real-World Context

International audienceAnalysis of human activities is a complex task that needs multifactorial considerations. So an electroencephalographic (EEG) data analysis can be improved by a conjunction of devices that monitor time courses of multiple types of physiological factors of the subject and counterparts when interactions are ongoing in the environment. In this article, we proposed a method to provide the complementary hardware and software treatment that associate devices to be able to synchronize simultaneous data recording to fit the high sampling rate of the EEG signal, such as more than 512 Hz. This method of synchronizing physiological data gathered from three different devices through the use of trigger signals is crucial for an accurate post-analysis and was validated in the experiment. The proposed method is widely applicable in various cases accompanied with EEG measurements and offer a wide possibility in device developments for rehabilitation and communications

CEPC Technical Design Report -- Accelerator

International audienceThe Circular Electron Positron Collider (CEPC) is a large scientific project initiated and hosted by China, fostered through extensive collaboration with international partners. The complex comprises four accelerators: a 30 GeV Linac, a 1.1 GeV Damping Ring, a Booster capable of achieving energies up to 180 GeV, and a Collider operating at varying energy modes (Z, W, H, and ttbar). The Linac and Damping Ring are situated on the surface, while the Booster and Collider are housed in a 100 km circumference underground tunnel, strategically accommodating future expansion with provisions for a Super Proton Proton Collider (SPPC). The CEPC primarily serves as a Higgs factory. In its baseline design with synchrotron radiation (SR) power of 30 MW per beam, it can achieve a luminosity of 5e34 /cm^2/s^1, resulting in an integrated luminosity of 13 /ab for two interaction points over a decade, producing 2.6 million Higgs bosons. Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons, facilitating precise measurements of Higgs coupling at sub-percent levels, exceeding the precision expected from the HL-LHC by an order of magnitude. This Technical Design Report (TDR) follows the Preliminary Conceptual Design Report (Pre-CDR, 2015) and the Conceptual Design Report (CDR, 2018), comprehensively detailing the machine's layout and performance, physical design and analysis, technical systems design, R&D and prototyping efforts, and associated civil engineering aspects. Additionally, it includes a cost estimate and a preliminary construction timeline, establishing a framework for forthcoming engineering design phase and site selection procedures. Construction is anticipated to begin around 2027-2028, pending government approval, with an estimated duration of 8 years. The commencement of experiments could potentially initiate in the mid-2030s