Real world consists of various kinds of natural and man-made objects, which are changing, moving, and interacting with each other dynamically. Capturing all these objects widely, continuously, and accurately is the rapidly growing subjects in the sensing technology. In order to use those vast information in the computerized network environment as precious resources, and make the best use of the corresponding physical objects as sustainable resources, we will show in this article how the ubiquitous sensing and networkin systems can be developed based on a tight coupling of sensing and wireless communication technologies, and based on a tight coupling of objects in the real world and information in somewhere in the network via a ubiquitous, automatic identification tag system.

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“Suica" is our contact-less IC-card's nickname: Super Urban Intelligent CArd. There are two types of Suica: 4.5 million Suica Commuter Pass with the stored fare (SF) function and 2 million Suica IO (SF) Cards have already been procured for ticket gate system. Suica can be used without taking the card from the pass-case, and the necessary fare will be extracted from the card automatically at the gate. Suica can be used repeatedly with the re-writing and reloading function. Suica Pass can be re-issued with the remaining stored fare when it is lost. There are 5.84 million Suica holders (about 2.94 million Suica Season Pass holders and 2.9 million Suica IO Card holders) as of 24, March 2003. Average reloading value amount is about 3, 000 Yens. There are almost 3 million transactions (not including the usage of Suica Pass inside the pass zone).

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This paper proposes a new location-awareness system, ALTAIR (Automatic Location Tracking system with Active IR-tag) that automatically detects and tracks the locations of the mobile PC (Personal Computer) users. IR(InfraRed)-tag is stably detected and distinguished from the scenery by IR filtering camera. Combination of the IR-tag and wireless LAN (Local Area Network) enables ALTAIR to control the timing and the lighting pattern of the IR-tags through the network to perform stable tracking for multiple users. To identify the user and the location, detected IR-tag position and its network information (e.g. IP address) are associated with each other. ALTAIR is capable of dynamic management of the users' entry and automatically starts to aware the user's position when he/she enters the system area, using DHCP (Dynamic Host Configuration Protocol) performances. Our experimental results show the effective performance in terms of precision and stability for tracking and identifying the users' positions in an office environment.

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Principles of the two-dimensional image reproduction with frequency components higher than Nyquist frequency of an image sensor using low-pass filters were considered, and resolution progress of an image sensor by digital signal processing was simulated on computer. Simulated image sensor is the two-dimensional (area) image sensor. After the simulation, it is difficult to find the differences between the original and the reproduced image by the naked eye. The reproduced images that have frequency components twice higher than Nyquist frequency were successfully obtained. Using this method, it is possible to enhance the resolution of conventional image sensor twice as high as its inherent resolution without any modification to the image sensor.

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In this paper, electrical and optical characteristics of artificial lipid membrane for basic taste solutions and tea drinks were examined. The possibility of taste sensing on the electrical and optical response patterns of a single membrane was also discussed. As a result, in case of sour and sweet solutions with different concentration, the patterns of taste response were similar in shape. In case of the tea drinks on some commercial goods, the different shapes among the sample solutions were obtained. Furthermore, the strength of sour taste was reflected in the electrical axis of response pattern and the strength of sweet taste was reflected in the optical axis of response pattern. Therefore, it was found that the possibility of taste sensing using electrical and optical response patterns was obtained from a single membrane.

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Three types of metal oxide gas sensors were adopted to detect the degree of breath odor. Various sorts of information are included in the odor. Each sensor has different sensitivities to gaseous chemical substances and the sensitivities also differ according to human behaviors, for example taking a meal, teeth-brushing and drinking something. There is also a possibility that the sensor can detect degrees of daily fatigue. Sensor sensitivities were low for the expiration of the elderly when the subject drank green tea. In this study, it is thought that the odor system can be incorporated into a healing robot. The robot can communicate with the elderly using several words and also connect to Internet. As for the results, the robot can identify basic human behaviors and recognize the living conditions of the resident. Moreover, it can also execute a kind of information retrieval through the Internet. Therefore, it has healing capability for the aged, and can also receive and transmit information.

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Determination of urea in rice wines was performed by using a spectrophotometric flow-injection analysis (FIA) system introducing an acid urease column as a recognition element. An acid urease, having specific properties of showing catalytic activity in low pH range and tolerance to ethanol in comparison to those of a urease from jack-beans, was covalently immobilized onto porous glass beads and then, packed into a small polymer column. This flow-type of the biosensing system was assembled with a sample injection valve, the immobilized enzyme column, a gas-diffusion unit, and a flow-through quartz cell attached to a UV/VIS detector. Standard urea solutions were measured through monitoring variations in absorbance resulting from pH shift due to ammonia molecules enzymatically generated. A wide, linear relationship was obtained between the concentration of urea (7.8 µM - 1.0 mM) and the change in absorbance. Followed by several investigations for application of this FIA system for measurement of urea in commercially available rice wines, the real samples were injected into the FIA system and urea in the samples were determined. These results were compared with those obtained with use of an F-kit method which was widely used for determination of urea. Comparative studies exhibited that this FIA system might be a powerful tool for urea determination in alcoholic beverages.

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Good adhesive nickel film was deposited on a glass substrate with electroless nickel plating and photolithography technique. Line-and-space metal patterns were deposited on the glass substrate and the resolution was approximately 20µm. Through holes on a 500µm-thickness glass substrate were fabricated by sandblast method, and the holes were metalized by using dry-film and the plating. Connection yield was 100% in 4cm² glass substrate, and the resistance of the through-hole was less than 0.05Ω.

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