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Niels Ehler and Jesper M. Aaslyng

The possibility of constructing an Internet application that would enable greenhouse users to track climate and control parameters from any Internet-connected computer was investigated. By constructing a set of HTML-templates, dynamic information from the control-system databases was integrated in real-time, and was uploaded to a common net-server by automatic generation of web pages using software developed during the project. Good performance, reliability and security were obtained and the technology proved to be an efficient way of supplying a broad range of users not only with climatic data but also with results from ongoing research.

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Niels Ehler, Mark A. Rose and Jesper Mazanti Hansen

Currently, greenhouse environmental computers are programmed to monitor and control the macroclimate instead of directly controlling plant growth and development, which are features of more interest to growers. Our objective was to develop a generic system to represent and control the dynamic plant processes that regulate plant growth in the greenhouse. Before plant growth can be directly controlled, the dynamic interactions between the microclimate around plants and plant physiological processes must be further understood. Future computerized control systems must be able to display an intuitive, interactive software program that helps the user understand and make use of the dynamic relationships between climate controls, climate processes, and plant processes. A conceptual framework was designed for a user interface with a biological orientation. This software consists of five different elements: the information provider, the information monitor, the information browser, the growth system controller, and the system visualizer. A demonstrator application illustrating this concept was developed and connected in real time to a standard greenhouse environmental computer. Crop tissue temperature is calculated and used instead of conventional irradiance limits to control shading screens to optimize the amount of radiation absorbed by the crop. The application is based on a set of generic automatically created paradox databases. A graphical user interface on the screen displays virtual plants that are used for visualizing, understanding, and controlling the different processes governing the crop tissue temperature.

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Paul R. Fisher, Royal D. Heins, Niels Ehler, Poul Karlsen, Michael Brogaard and J. Heinrich Lieth

Commercial production of Easter lily (Lilium longiflorum Thunb.) requires precise temperature control to ensure that the crop flowers in time for Easter sales. The objective of this project was to develop and validate a greenhouse decision-support system (DSS) for producing Easter lily to predetermined height and flower date specifications. Existing developmental models were integrated with a knowledge-based system in a DSS to provide temperature recommendations optimized for Easter lily scheduling and height control. Climate data are automatically recorded in real time by linking the DSS to a greenhouse climate control computer. Set point recommendations from the DSS can be manually set or automatically implemented in real time. Potential benefits of the project include improved crop quality and the transfer, validation, and integration of research-based models. The DSS was implemented at several research and commercial locations during the 1994 Easter lily season. DSS recommendations were compared with the strategies of experienced growers. The system design, implementation, production results, quality of recommendations, and potential are discussed.