Several papers on environmental conditions in the Controlled Green-house have been reported (I-V) .
In this paper (VI), spectrum analysis of temperature fluctuation in the Controlled Green-house is discussed.
Characteristics of frequency response functions between input air-flow and output temperature in the room with cucumbers are discussed upon the result from the fundamental discussion of spectrum analysis. Cucumbers are set as two pots per m². As a result, the following (1), (2) are concluded.
(1) Gains of frequency response functions in higher frequency components (1 Hz-5 Hz) at several points in the room are nearly equal, and system of response is nearly linear.
(2) Gain of frequency response function in lower frequency components (0 Hz-1 Hz) at any point in the room is different from at another point in the room, and system of response is nearly non-linear.

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The effect of air movements on leaf temperature was analyzed under various environmental conditions in a growth cabinet, by inserting a micro-thermistor into a cotyledon of Cucurbita maxima “Tokyo-wase” seedling, and the following points of interest became clear:
1) The difference between air temperature and leaf temperature was reduced by air movement.
2) The effect of air movements on leaf temperature was enhanced with the increased velocities within a range of 0.6 m/sec to 4.8 m/sec.
3) The effect of air movement at a velocity of 1.2 m/sec on leaf temperature was altered by relative humidity at an air temperature of 40°C, but it was not affected at an air temperature of 20°C.

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[in Japanese]

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In order to obtain inexpensive and widely applicable wavelength independent (neutral) filters for adjusting the light intensity in biological experiments, measurements were made on various materials including newly developed plastic films.
With various white papers the spectral transmission in the visible (VIS) and near infrared (IR) regions was almost uniform but with the greater part of transmitted light it was diffused. Cheese cloth showed excellent characteristics in that with every kind of cheese cloth a wide spectral range, from ultraviolet (UV) to IR, could be transmitted at an equal rate. They also did not diffuse transmitted light very much, especially black cheese cloth.
Some translucent polyethylene (PE) films were generally not suitable for use as neutral filters because transmission depended on wavelength. Using newly produced gray colored PE and polyvinyl chloride (PVC) films, however, transmission in a wide spectral range was very uniform and the diffusion of transmitted light was not excessive. Thus, it appeared that the gray plastic films, especially the 0.02-mm-thick PE films, are useful as neutral filters.

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