The purpose of this study is to analyze the thermal environment inside greenhouse by means of system identification and to indicate the applicability of system identification. The experiment was carried out in a vinyl house with the floor area of 58 m² and the surface area of 190 m² in July and August of 1991.
At first, the authors investigated the mechanism which determines the thermal environment inside greenhouse under no ventilation. The assumed mechanism is shown in Fig. 1. The measurement points in this experiment are shown in Fig. 2. Figure 3 is the block diagram of the heat flow which expresses the assumed mechanism of Fig, 1.
The results of identification of a system with an input of radiation outside greenhouse and an output of air temperature at the point 2M are shown in Fig. 4. The calculated air temperature is in good accordance with the measured air temperature. The step response indicates that increase of 1 kW⋅m^-2 in radiation causes increase of about 30°C of inside air temperature. Figure 5 shows the relationship between order and error in identification of the system.
The results of identification of a system with an input of air temperature at the point 2L and an output of air temperature at the point 2M are shown in Fig. 6.
Figure 7 shows the measured and calculated air temperature at the point 2M. Calculation was executed according to the block diagram of Fig. 3 from radiation outside greenhouse.
Furthermore, the authors investigated the mechanism where the thermal environment inside greenhouse is determined by both radiation and ventilation. The block diagram of system which determines air temperature at the point 2M based on radiation outside greenhouse and on-off of ventilating fan is shown in Fig. 8. Figure 9 shows the results of identification, indicating that system identification is effective in analysis of condition with on-off of ventilating fan.
Figure 10 shows the results of identification of the same system of Fig. 4. In Fig. 10, identification was made for every 3 hr and the calculated air temperature was linked. The calculated air temperature is in much better accordance with the measured air temperature than that of Fig. 4, indicating that system of greenhouse is changing slowly and that the latest data is needed for more precise calculation of the system.

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Composting heat generator is a low level heat source compared with those using combustion of fuels such as petroleum and LNG. Because it is low level in temperature, composting heat generator will not be applied to heat recovery system unless it is designed to restrict energy loss and exergy dissipation as little as possible. Exergy is known to be useful to evaluate the availability of every kind of energy not only from its quantity but also from its quality.
For optimization of a target heat recovery system from composting heat generator, mass, energy and exergy balances must be predicted properly under any possible operating condition. Because there is a temperature difference between the heat generator and medium fluid in a heat exchanger inserted in the generator, temperature does not become uniform in the generator. In order to predict the amount of energy and exergy recovered from such heat generators of non-uniform temperature in detail, the balance equations must be treated microscopically.
In the present paper, microscopic balance equations of mass, energy and exergy in the composting heat generator are derived systematically, following a transport phenomena model with chemical reaction for porous or dispersed media. Then, the balance equations are simplified to equations of practically available form, because the mass flux by diffusion can be neglected compared with that by convection under the usual aerating condition of composting.
The amount of heat and exergy possible to be recovered will be theoretically predicted by solving the balance equations derived here with suitable boundary and initial conditions introduced for the target heat recovery system.

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The validity of the microscopic balance equations proposed in Part 1 is discussed, based on the experimental results of heat recovery from a composting heat generator using a trial heat exchanger.
The calculated result of the final apparent density of compost materials packed in the generator is about 10% larger than the experimental result, because there was a gravitational leakage of water from the bottom of the generator in this experiment. However, the calculated results of temperature in the generator, temperature of medium fluid at the outlet of the heat exchanger, and distributions of the generated heat and exergy show relatively good agreement with the experimental results of them. Therefore, the theoretical treatment based on the microscopic balance equations seems likely to be valid to simulate the heat recovery system from the composting heat generator.
In this experiment, maximum amount of exergy possible to be recovered is about 4%, which is smaller than the value previously estimated under the assumption of perfect mixing of compost materials. It is due to heat conduction occurring in the generator during heat recovery.
On the other hand, the amount of exergy actually recovered by medium fluid is merely 0.3% of the whole amount of exergy generated in composting, and almost all the amount of generated exergy is lost out of the heat generator or dissipated due to irreversibility of the process.
To make larger the enthalpy and exergy efficiencies, the following methods will be advantageous, that is, 1) Introduction of external heat recovery system from exhaust air out of heat generator, and 2) Change of the medium fluid in the heat exchanger from water to air.

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発芽性が悪いといわれるニンジン種了を用いて, 発芽と生育の促進をはかるため, 各種濃度のオゾンに浸漬した種子を暴露し, 発芽率, 平均発芽日数および15日後の初期生育におよぼす影響を調べた.
1.高濃度 (3～5ppm) ・長時間 (2～3日) 暴露 (高レベル処理) では, 発芽率はいくぶん向上したが, 平均発芽日数には効果はみられず, 初期生育は暴露が長いほど抑制的であった.
2.低濃度 (0.1～2ppm) ・短時間 (1日) 暴露 (低レベル処理) では, 発芽率はどの濃度でも向上し, とくに0.1～0.5ppm程度が良好であった.平均発芽日数はあまり変わらなかった.また, 初期生育は0.5ppm時によい結果を示した.
3.概してオゾン処理は, 平均発芽日数の短縮は困難であったが, 低レベルの適正な条件では, 発芽率, 初期生育とも向上した.とくに0.5ppmで1日程度の暴露が良好であった.

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育苗期のイチゴ‘女峰’のシンク活性, 養分吸収に及ぼす短日や低温条件の影響を検討した.処理は無処理, 短日 (8hr) , 低温 (DT/NT=25/10℃) と, その後の夜冷処理 (DT/NT=放任/10℃) を組み合わせ, 計6区とし, 処理期間は4週間とした.
根の乾物重は夜冷処理により増加した.短日と低温のいずれの処理によっても, 葉の全炭素含有率は低下し, リン, カリウム含有率は増加した.¹³C光合成産物の根への分配は, 短日と低温処理により低下したが, 夜冷処理により増加した.根のシンク強度も, 夜冷処理により増加した.同様の傾向はクラウンのシンク活性についても認められた.
以上の結果, 夜冷処理はクラウンおよび根のシンク活性を増大させ, 葉からの光合成産物の転流を促進した.このことは, クラウンならびに根の生育を促進し, 花成に寄与するものと思われた.

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挿し木で養成した鉢植えの3年生ブドウ台木, 3309, 3306, 101-14, 5BB, SO・4, 110RおよびH.F.の7品種について, 6月3日から9週間, 簡易ハウス内で湛水処理を行い, 樹体の生長ならびに体内の生理的変化に及ぼす影響を調査した.新梢生長, 葉のクロロシス, 落葉などからみた耐湿性は台木品種によって著しく異なり, 3306やSO・4で強く, 110RやH.F.で弱かった.3309, 101-14および5BBの耐湿性はこれらの中間であった.気根の発生時期には品種間に差がなかったが, 発生量はH.F.で最も多く, 110RとSO・4で少なかった.葉のクロロフィル含量, 根の代謝活性, 根のエタノール生産量ともに台木品種によって著しく異なったが, 品種間でのこれらの差異と耐湿性の品種間差異との間には明確な関係が認められなかった.

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