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Despite their high energy consumption, office thermal comfort delivery mechanisms perform poorly. The recently enacted environmental protection policies, which require a significant cutback in greenhouse gas emission, can only exacerbate this situation because, given the limitations of current thermal comfort provision technologies, a reduction in energy would translate into an increased thermal discomfort in offices. Hence, this dilemma entails alternative thermal comfort delivery systems that provide higher quality thermal comfort at lower energy. This paper proposes to use physiologically-controlled thermal comfort controllers to achieve this. It also discusses advantages of this novel approach, highlights potential unobtrusive thermal comfort biomarkers, and presents the necessary steps in designing such systems. Finally, the paper briefly discusses some of our preliminary results that showcase the feasibility of such a system.

Wearable devices are currently popular for fitness tracking. However, these general usage devices only can track limited and prespecified exercises. In our previous work, we introduced ExerSense that segments, classifies, and counts multiple physical exercises in real-time based on a correlation method. It also can track user-specified exercises collected only one motion in advance. This paper is the extension of that work. We collected acceleration data for five types of regular exercises by four different wearable devices. To find the best accurate device and its position for multiple exercise recognition, we conducted 50 times random validations. Our result shows the robustness of ExerSense, working well with various devices. Among the four general usage devices, the chest-mounted sensor is the best for our target exercises, and the upper-arm-mounted smartphone is a close second. The wrist-mounted smartwatch is third, and the worst one is the ear-mounted sensor.

To face the decrease of lifestyle comfort, the augmentation of hypothermia risks, and the deterioration of labor productivity resulting from energy consumption reduction policies, we have been proposing a wearable air-conditioning device worn like a scarf. This paper reports evaluation results of this wearable air-conditioning device’s effectiveness regarding comfort in hot summer office environment. We studied through trial subjects how neck cooling affects (1) subjective evaluation on comfort, thermic, and sweat sensations, and (2) human physiology when performing various deskwork tasks in summer heat environment. The environment of a typical Japanese office space in summer heat were reproduced using an environment control room. The environment control room’s temperature, humidity and wind velocity were set to re-create summer heat office environment (32°C, 60%, 0.15 m/s). 16 healthy subjects sat in the room in both normal condition and neck cooling condition. All subjects were dressed respecting the standard “cool-biz” dress code in Japan. (1) Comfort sensation, thermic sensation, and sweat sensation were evaluated by self-assessment. For all subjects, both discomfort sensation, heat sensation, and humidity sensation increased together with room temperature elevation, such we can understand that there is a clear correlation between environment temperature and comfort regarding temperature sensation. (2) Furthermore, we could quantitatively define the correlation between self-assessment, temperature variations, and physiological signals such as sweat amount and heart rate variability, by investigating the individual differences for comfort/discomfort in both normal and neck cooling conditions. Experimental results of this study show that using the wearable air-conditioning device in summer heat office, air-conditioner can be turned off or temperature set higher, without affecting comfort.

This paper describes wireless wearable and ambient sensors that cooperate to monitor a person’s vital signs such as heart rate and blood pressure during daily activities. Each wearable sensor is attached on different parts of the body. The wearable sensors require a high sampling rate and time synchronization to provide a precise analysis of the received signals. The trigger signal for synchronization is provided by the ambient sensors, which detect the user’s presence. The Bluetooth and IEEE 802.15.4 wireless technologies are used for real-time sensing and time synchronization. Thus, this wearable health-monitoring sensor response is closely related to the context in which it is being used. Experimental results indicate that the system simultaneously provides information about the user’s location and vital signs, and the synchronized wearable sensors successfully measures vital signs with a 1 ms resolution.

Continuous monitoring of eating habits could be useful in preventing lifestyle diseases such as metabolic syndrome. Conventional methods consist of self-reporting and calculating mastication frequency based on the myoelectric potential of the masseter muscle. Both these methods are significant burdens for the user. We developed a non-invasive, wearable sensing system that can record eating habits over a long period of time in daily life. Our sensing system is composed of two bone conduction microphones placed in the ears that send internal body sound data to a portable IC recorder. Applying frequency spectrum analysis on the collected sound data, we could not only count the number of mastications during eating, but also accurately differentiate between eating, drinking, and speaking activities. This information can be used to evaluate the regularity of meals. Moreover, we were able to analyze sound features to classify the types of foods eaten by food texture.

Continuous monitoring of blood pressure in daily life could improve early detection of cardiovascular disorders, as well as promoting healthcare. Conventional ambulatory blood pressure monitoring (ABPM) equipment can measure blood pressure at regular intervals for 24 hours, but is limited by long measuring time, low sampling rate, and constrained measuring posture. In this paper, we demonstrate a new method for continuous real-time measurement of blood pressure during daily activities. Our method is based on blood pressure estimation from pulse wave velocity (PWV) calculation, which formula we improved to take into account changes in the inner diameter of blood vessels. Blood pressure estimation results using our new method showed a greater precision of measured data during exercise, and a better accuracy than the conventional PWV method.