An small deep-placement fertilizer applicator (SDFA), to realize hill fertilization application and mark fertilizer location with lime, was developed. It’s unique structure and working principle were detailed. Orthogonal tests was conducted by the software EDEM virtual simulation in order get the working parameters and structure of the applicator. The rotational torque was much higher than resistant torque after optimization design. Field testing across different sites and seasons showed that the improved applicator consistently placed synthetic fertilizer at the depth of 18–21 cm and plant spacing of 49–52 cm. The average amount of fertilizer released into each hill was 54.5 g when the set amount was 55.0 g, which indicate the design are effective.

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This paper aims to propose a measurement method for track tension fluctuation, which focuses on the inner structure of the rubber track. This capacitance variation in the rubber track's structure of capacitors constructed with a steel cord as a capacitor plate and the rubber between the steel cords as the electric material was measured in the oscillating frequency by a CR oscillating circuit that utilized the characteristic of a capacitor. As a results, it was theoretically confirmed that the oscillating frequency was reduced by increasing the tension load, and a stable value with a high correlation between the tension load and the oscillating frequency. In conclusion, this study has demonstrated the possibility for stable measurement of crawler tension.

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In this research, 4 Rapideye satellite images and 8 UAV (unmanned aerial vehicle) images are used covering 2 different varieties of winter wheat fields, in order to analyze the correlation among satellite images based normalized difference vegetation index (NDVI) with the UAV images based visible-band difference vegetation index (VDVI) and ground variable of grain protein contents. The results showed that NDVI related most to the grain protein content at the later stage of wheat growing season, 1 week prior to harvesting. And the linear-regression models for field No. 1 and field No. 2 of NDVI with VDVI showed good consistency at the early stage of wheat growing season, with the coefficient of determination R² = 0.62 and 0.86, respectively

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Low-intensity (0.05–1 V_pp / cm (peak to peak voltage per cm)) and high frequency (10–100 MHz) alternating electric fields accelerate seed germination. One V_pp / cm, 100 MHz alternating electric field application for 10 h significantly shortened germination time of arugula, Japanese mustard spinach, and pea seeds, respectively. The germination rates of the electric field applied plant seeds were enhanced 1.5–2.2 times compared to the untreated seeds, respectively. After 72 h of the incubation, the 1 V_pp / cm, 100 MHz alternating electric field for 10 h significantly increased 1.4 folds of culm lengths in the arugula, the Japanese mustard spinach, and the pea seeds compared with those of the untreated seeds.

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