Supplemental lighting sources in greenhouses are accompanied by generation of considerable amounts of heat. However, the engineering methods regarding this contribution to greenhouse heating are rarely recognized. This study was conducted to evaluate the experimental and theoretical heat gains from supplemental lighting and their contributions to greenhouse heating. The experimental greenhouse had glass covers and 100 m² floor area, and 21 high pressure sodium lamps of 250 W were used as the light source. The greenhouse operated with thermal screens at night in winter and spring. The heat gain from lighting for 5 h a day was evaluated to be maximum 91.3 MJ, and the effective contributions of lighting to heating were evaluated to be between 12.8% and 72.2%.

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We established the method with finite element analysis of the running tire using an anisotropic elastic wheel model that includes the vertical and horizontal rigidities and inspected it about validity by the experimental results of the running performance and the contact pressure distribution for different inflation pressures. The contact normal stress was greater in the front half of the ground. It was a flat distribution in the vicinity of the maximum value. The running resistance and the contact load obtained by integrating measurement results of contact normal stress are almost equals to the results of calculation by drawbar pull and torque. The calculated coefficients of net traction for the experimental conditions were in good agreement with the experimentally determined values.

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Quantitative somatic cell count (SCC) measurement for detection of mastitis using an attenuated total reflectance (ATR) terahertz (THz) spectroscopy was investigated. Using samples with controlled SCC derived from raw milk, we measured their ATR signal in the THz region 30–440 cm⁻¹ with a Fourier-Transform THz spectrometer. We found ATR signals decreased as SCC increased. Furthermore, we found the correlation between the ATR signal and SCC from 8.0 × 10⁴ to 1.57 × 10⁶ cells/mL was optimal at 139 cm⁻¹ (R² = 0.98). These findings demonstrate a potential to detect mastitis with a monochromatic THz wave.

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Chernozem is a soil group with calcium carbonate which is found extensively throughout the Heilongjiang province of the People's Republic of China. As one of the main corn belts in the world, the area has continuous planting of corn every year, but that lead to continuous cropping injury. Many corn stalks remain on the soil surface in autumn, so these corn stalks should be buried into the subsoil to retain rainwater underground. This can be accomplished with a special plough which we newly designed and built in this paper. The results show that when the corn stalk length was less than 1000 mm, a smooth burial took place. A total draught of this plough was measured at about 35 kN.

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Due to many advantages, natural fibers have been of great interest recently in many researches and industries. Calotropis stem has valuable fibers with various applications in the industry. Regarding this; a fiber extracting machine is designed and constructed, based on mechanical method. The machine per- formance is evaluated in this research as well. The machine consists of three separation units and two feeding units. Each separation unit is comprised of; a frame, a pair of blades, a pair of roller, two yoke and power transmission system. Some physical and mechanical properties of stems and barks are determined as predesigning steps. Analyzing extracting efficiency at three speed levels and two moisture contents shows that the maximum extracting efficiency (with 98%) is at rotational velocity of 40 rpm with the moisture content of 75% w.b. Experimental test shows that maximum consumed power was about 958 W while whole stem is located in the machine. The capacity of extraction machine based on dried mass of barks and fibers was 2 kg/h approximately.

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The objective of this study was to detect cabbage seedling diseases by using a self-developed chlorophyll fluorescence imaging system. Commercially available blue light sources with a wavelength ranging between 430 nm and 480 nm were used to excite fluorescence. A filter with a wavelength of 684 ± 10 nm attached to a near-infrared camera was used to capture the image of fluorescence emitted by the cabbage seedlings. The experimental results indicated that using the chlorophyll fluorescence imaging system, leaf spots on cabbage seedlings were detected 8 h earlier compared with using a charge-coupled device camera. Based on this finding, the proposed chlorophyll fluorescence imaging system can be used to develop early detection systems for cabbage seedling leaf spots.

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When the micro-tiller is applied to agricultural tillage on farmland in the hilly rural areas of south-western China, there are two major issues. One is highly variable cutting depth; the other is the quite difficult manual labor. In order to improve the tillage quality of the micro-tiller and relieve the operator's manual labor, Auxiliary Depth-control System (ADS), which mainly consists of a detector, a controller, an actuator and a display interface, is designed in this paper. It is used to display real-time cutting depth and control the reciprocating motion of the resistance rod of the micro-tiller. The field tests showed that ADS improved the consistency of cutting depth because the coefficient of variation of the consistency of cutting depth decreased from 11.59% by the micro-tiller with traditional resistance rod to 5.82% by that with ADS, meeting the agronomic requirement of fewer than 10%. Meanwhile, the manual labor required was alleviated as labor intensity index decreased from 20 to 18 after usage of ADS in the micro-tiller. That could prove the significance of ADS in future micro-tiller design.

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Sensory evaluation involves the measurement and examination of the sensory properties of foods. This paper deals with the use of some chemometrics techniques for sensory recognition and stability of four Iranian pistachio nut varieties (Kale-Ghouchi, Akbari, Ohadi, and Momtaz) during storage. For this purpose, nine sensory attributes (bitterness, firmness, sweetness, rancidity, crunchiness, salty, sour, glossy, roasted) were evaluated by a professional trained human sensory panel to examine the changes during 8 months of storage. Several chemometrics techniques were employed for this aim. Linear techniques as principal component analysis (PCA) and Linear Discriminant Analysis (LDA) were performed over the data that partial overlapping were seen for all treatments of pistachio nut varieties. Moreover, artificial neural networks such as Probabilistic Neural Networks (PNN) with Radial Basis Functions (RBF) and FeedForward Networks with Backpropagation (BP) learning method were then used. The methods have proved a good capability to recognize and classify the stored pistachio nuts satisfactorily in such a way, for whole varieties, high classification accuracies were obtained. The highest success rate was found for Kale-Ghouchi variety (D) as 100%. It was revealed the classification accuracies were better using BP compared with PNN. The achievements of this study can be of great interest to pistachio nut producers for the management of storage length and more particularly export circumstances. The results obtained can be used as a reference data for electronic nose and electronic tongue experiments in future studies.

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To improve the efficiency and accuracy of water-nutrient mixing, a multi-channel fertigation machine was designed; the hardware includes a programmable logic controller (PLC), a touch system and multi- channel sensors. A sectional forecast control algorithm based on the nutrient dilution model was pro- posed to control the fertigation machine. When the 100-fold concentrated nutrient solution was diluted by a factor of 20–200, the results showed that the standard deviations of the electrical conductivity (Ec) and the pH for four repeat measurements were 0–0.4 mS cm⁻¹ and 0.057–0.12, respectively; therefore, the performance of the nutrient solution was stable. When the target Ec values were 1.0, 1.5, 2.0, 2.5, 3.0 and 4.0 mS cm⁻¹, the variation coefficients relative to the target Ec values for three repeat measurements were 2%, 0.94%, 0.87%, 0.63%, 2.37% and 1.8%, respectively. The multi-channel water-nutrient mix resulting from the sectional forecast control algorithm was precise; the error of the Ec was less than 0.05 mS cm⁻¹, which satisfies the requirements of fertigation for soilless cultivation in greenhouses.

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