A decision-support system for real-time management of Easter lily (Lilium longiflorum Thunb.) scheduling and height--I. System description
Abstract A decision-support system was developed for recommending night and day temperature settings to control the timing and height of Easter lily ( Lilium longiflorum Thunb.). Existing biological models and qualitative rules were combined into an overall model of the response of plant development rate to temperature. A process control algorithm was used to determine appropriate height control actions based on a graphical control chart of plant height over time. A knowledge-based system checked the feasibility of output from the development and height control models and generated a text report. This model was implemented on a personal computer in a program called “The Greenhouse CARE System” and has been linked directly with an environmental computer to control greenhouse temperatures. A companion article describes validation of this model.
Temperature Effects on ‘Nellie White’ Flower Bud Development

Lilium longiflorum Thunb. ‘Nellie White’ flower buds developed from visible bud to open flower more rapidly at constant 27°C than at constant 15°. This increased growth rate was most pronounced when buds were less than 6 cm. Once buds were greater than 10 cm, the differences in rate of flower bud growth at 15° compare to 27° was insignificant. Bud development was biphasic, with a relatively slow growth rate up to 6 cm and then an accelerated rate from 6 cm to open flower. The fitted regression line for buds less than 6 cm was: days to flower (DTF) = 37.969 - 8.945 Ln [bud length (L)] — 0.453 [(Temperature (T)]; for buds greater than 6 cm: DTF = 33.258 — 2.039 (L) - 0.736 (T) + 0.044 (L x T). The correlation coefficients for the 2 equations were respectively: r = 0.82 (R2 = 0.67) and r = 0.93 (R2 = 0.87).
Hydrogen-rich gas production from biomass air and oxygen/steam gasification in a downdraft gasifier
Biomass gasification is an important method to obtain renewable hydrogen. However, this technology still stagnates in a laboratory scale because of its high-energy consumption. In order to get maximum hydrogen yield and decrease energy consumption, this study applies a self-heated downdraft gasifier as the reactor and uses char as the catalyst to study the characteristics of hydrogen production from biomass gasification. Air and oxygen/steam are utilized as the gasifying agents. The experimental results indicate that compared to biomass air gasification, biomass oxygen/steam gasification improves hydrogen yield depending on the volume of downdraft gasifier, and also nearly doubles the heating value of fuel gas. The maximum lower heating value of fuel gas reaches 11.11MJ/Nm3 for biomass oxygen/steam gasification. Over the ranges of operating conditions examined, the maximum hydrogen yield reaches 45.16gH2/kg biomass. For biomass oxygen/steam gasification, the content of H2 and CO reaches 63.27–72.56%, while the content of H2 and CO gets to 52.19–63.31% for biomass air gasification. The ratio of H2/CO for biomass oxygen/steam gasification reaches 0.70–0.90, which is lower than that of biomass air gasification, 1.06–1.27. The experimental and comparison results prove that biomass oxygen/steam gasification in a downdraft gasifier is an effective, relatively low energy consumption technology for hydrogen-rich gas production.