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Recently, much attention is paid on the plant factory, as it enable to grow plants stably under extraordinary climate condition such as high and/or low air temperature and less rain. Lots of questions such as decreasing investing cost, realizing stable plant production and developing new growing technique should be solved for making popular this growing system. However, I think that we can introduce a highly developed Japanese industrial now-how to plant factory system and can produce a business chance to the world market.

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It is well known that soil water at a farm land seriously affects on growth and quality of crops. Therefore, although several methods for monitoring of soil water have been developed. We developed a hetero-core optical fiber SPR sensor which are evaporated with Au for sensing a drop of soil gravity water. We set the sensor at 5 cm in depth from the top of soil and connected it to both a LED light source and a power meter. As the result, the loss in light going through inside of the optical fibers became from 0.06dB to 1.21dB in 10-60 seconds after watering, and the gain in light became from 0.03dB to 0.17dB in a matter of time. According to the result, it was proved that to detect soil gravity water is possible and in soils the detection ability of the sensor can return which is caused by evaporating of water on the surface of the sensor by air in a soil.

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Our group has studied on-site monitoring sensor for agricultural field. An electrical conductivity (EC) sensor had been fabricated using Si integrated circuit technology. EC information of solutions shows ion concentrations dissolving in water, and can be used as the index of nutrient concentration for plants. So, it is important to measure EC in real time and on site. Because our EC sensor (5mm×5mm in size) is smaller than other commercial ones (several centimeters), it is easy to insert and achieve measurement in rock wool. In this study, our sensor measured long term EC values in tomato cultivation soil and rock wool medium. At first, we calibrated a relationship between output voltages and EC values on the sensor. The sensor was confirmed about enough EC measurement range from 8 to 969mS/m. In long period measurement, the sensor was confirmed about continuous operation for over five months, and intermittent measurement for over a year. In measurement in the cultivation soil, the sensor indicated that water was kept and diffused in the soil. In contrast, it was found that water diffused without keeping in it in rock wool medium. We confirmed our small EC sensor is useful for on-site monitoring and analysis of solution concentration distribution in several kinds of cultivation bed in real time.

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Electrochemical microdevices were fabricated to identify mastitic cows based on the increased number of neutrophils in raw milk. Because neutrophils produce superoxide (O₂^·-), the amount of O₂^·- can be used as an early indicator for subclinical mastitis. In the microdevices, O₂^·- was detected on a gold electrode using superoxide dismutase immobilized via a self-assembled monolayer of cysteine. In a preliminary test using xanthine oxidase to produce O₂^·-, one of the devices detected the production and rapid extinction of O₂^·-. When neutrophils obtained from a mastitic cow were concentrated by centrifugation and introduced into the device, a current increase distinctly different from the background was observed. Furthermore, a micropillar structure was fabricated on the gold electrode to trap and collect neutrophils, thereby facilitating the concentration of these cells around the electrode. The measured current clearly depended on the number of neutrophils in raw milk samples, demonstrating the applicability of the device for rapid diagnosis of subclinical mastitis.

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The system watching over elder's life is very important in a super-aged society Japan. In this paper, we describe a method to recognize resident's daily activities by means of using the information of indoor ambient atmosphere changes. The measuring targets of environmental changes are of gas and smell, temperature, humidity, and brightness. Those changes have much relation with resident's daily activities. The measurement system with 7 sensors (4 gas sensors, a thermistor, humidity sensor, and CdS light sensor) was developed for getting indoor ambient atmosphere changes. Some measurements were done in a one-room type residential space. 21 dimensional activity vectors were composed for each daily activity from acquired data. Those vectors were classified into 9 categories that were main activities by using Self-Organizing Map (SOM) method. From the result, it was found that the recognition of main daily activities based on information on indoor ambient atmosphere changes is possible. Moreover, we also describe the method for getting information of local gas and smell environmental changes. Gas and smell environmental changes are related with daily activities, especially very important action, eating and drinking. And, local information enables the relation of the place and the activity. For such a purpose, a gas sensing module with the operation function that synchronizes with human detection signal was developed and evaluated. From the result, the sensor module had the ability to acquire and to emphasize local gas environment changes caused by the person's activity.

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The novel mist-jet technology using a silicon nozzle and a silicon reflector has been developed. Ejection of water mist containing the silicon microparticles is demonstrated. Impurities of the silicon microparticles ejected on the substrate are analyzed. It has been verified for the first time that the contamination is reduced by the silicon head. The silicon pattern drawn by the head is successfully formed.

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