Takehiko Hoshi

A daily harvest prediction model of cherry tomatoes by mining from past averaging data and using topological case-based modeling

Abstract A daily harvest prediction model for an individual plant production system is proposed. The model is based on data mining and topological case-based modeling. Environmental measurement data that was logged by an environmental control computer in a greenhouse, daily working hours and daily harvest records were averaged for each period. Each averaged data was correlated with harvest on the object day. The calculated squared correlation values were visualized with the 3D graphs. The graphs helped to understand the relationship between the daily harvest and each factor that influenced the harvest. The model was applied to a greenhouse for producing cherry tomatoes. Four variables, which were harvest in the past, the numeric code of the day of the week, total working hours and daily difference of air temperature, were chosen for developing the predicting model in the data mining process. The chosen data was quantized and placed on the case-base cells in the computer memory. The topological case-based modeling used the principle of continuous mapping to predict the daily harvest. The least error of the predicted yield by the developed model was ±31 kg day −1 (26%) in the greenhouse.

Visualization System of Environmental Information on Internet

摘要インターネット上での環境情報可視化システムのプロトタイプとして, 気象観測システムを例としてとりあげ, システムの開発を行った。システムの機能は, PPP, SMTPなどのプロトコルを用いたメールでのデータ転送, WWWによるデータ配信, CGIスクリプトを用いたWWW上での測定データのメッシュ化と三次元可視化などである。以上のようなシステムにより, 従来のシステムより詳細なデータをユーザーへ簡単に送ることが可能であることを示した。特に, WWW上での三次元可視化システムは, 景観評価などにおいても, さまざまな利用方法があると考えられる。

An Object-oriented environmental control model in protected cultivation

Abstract A prototype computer model based on object-oriented approaches for environmental control in protected cultivation was discussed. The model handled to convert the control setpoints having generic form into the real manipulations of specific control instruments for measurement and control. The requests for environmental control were realized to send a message to specific object, and the object started to manipulate the control. The model did not need to take notice of any instruments specification, because each instrument specification was controlled by the specific object. A prototype system based on the concept was developed and tested. From the result of testing, the object-oriented approaches provided the prototype system with having flexibility, having reliability and saving development costs.

Design Concepts of Computerized Support Systems for Large-Scale Transplant Production

In large-scale transplant production systems, the adoption of production support systems by computers is indispensable. The design concept of two types of support systems, an autonomic decentralized production control system using the object-oriented programming technique and a production planning system that was based on each order were proposed. The results of computer simulation using the prototype systems were also reported. The control system developed on the autonomic decentralized concept could be scaled up to large-scale transplant production systems. The planning system could make a proper production plan for a transplant production system that consisted of many orders. Concepts of these support systems should be very effective to develop and manage large-scale transplant production systems.

Yield Forecast of Cherry Tomatoes by a Topological Case Based Modeling System

Abstract A daily yield forecast system for cherry tomato production equipment that was harvested every day in a large-scale greenhouse was developed. The forecast system was based on a data mining system and a topological case based modeling system by a personal computer. Four variables for forecast, yield in the past, numeric code of day of the week, total working hours and daily difference of air temperature, were chosen by the step-wise multiple regression analysis. The average error of the forecasted yield by the developed system was ±31.37 kg day-1 (25.6%). The results of the data mining, the factors that influenced the daily yield of cherry tomatoes, were manpower and the past yield rather than environment.

An Object-Oriented Plant Growth Modeling Support System Based Upon Cumulation of Environments

Abstract A plant growth modeling support system which was programmed in Smalltalk was developed and tested. The measured environment data was automatically received from the greenhouse controller through the computer network, and was cumulated by the system. The system used the cumulated data to simulate the plant growth. The system was the first step to construct the plant growth control expert system which related the environmental data with the plant growth.