This study surveyed the information for development of mechanical transplanting of leafy vegetables. The priority production area of each crop, cultivation season, primary cultivar, transplanting method, and cultivation practice, in terms of furrow, ridge, and planting distance, were determined. The cultivation region, cultivation period, seedling, transplanting method, and size of furrow and ridge for cultivation of kimchi cabbage, cabbage, broccoli, and head lettuce were determined. These activities were carried out on commercial farms in the main producing region of leafy vegetables. Regarding kimchi cabbage, the standard sizes of furrow and ridge were 63 and 13 cm, respectively. The suitable wheel distance of the transplanting machine was 112–136 cm and the planting distance of kimchi cabbage was 65 × 45 cm. For cabbage transplanted in a single row, the furrow and ridge sizes were 76–90 and 13–15 cm, and the wheel distance and planting distance ranged from 152–180 and 76–90 × 45 cm, respectively. For broccoli and head lettuce, respectively, the furrow size range indicated 50–78 and 63–69 cm, with corresponding ridges of 10–20 and 12–13 cm, and the suggested wheel distances were 100–156 and 126–138 cm. In addition, the planting distance of broccoli and head lettuce represented 76–90 × 45 cm and 63–69 × 30 cm, respectively. Results indicated the optimal density for mechanized transplanting of various types of leafy vegetables and the information provided could be applied to develop the specification of the machine’s end effects.

As interest in the variable rate application (VRA) increases, it is necessary to study the characteristics of the nozzle pressure applied for unmanned aerial applications. In this study, therefore, we analyzed the performance of nozzle pressure responses to the ground velocity in an unmanned rotorcraft test bed. Then, the responses using air chamber and Kalman filter were compared for reducing the pulsation and time delay. For the VRA system test, an unmanned agricultural rotorcraft with a commercial controller was used as a test bed for the VRA of the aerial pesticide application. The VRA system responses with air chamber and Kalman filter were measured when the system was switched on and off during flight maneuvers. Then, the lag time and pulsation were determined. Pulsation of nozzle pressure has been conventionally relieved using an air chamber, but the response of the nozzle pressure is delayed by 2.6–3.8 s. This delay could lead to a significant error in the application rate and uniformity in the case of high spraying speeds. Therefore, the air chamber method was excluded from the use in variable control applications. As an alternative, the pressure response was gently induced by employing the Kalman filter in the control S/W. The optimal covariances of the Kalman filter were found to be R = 100 and Q = 1, and the response time of the nozzle pressure was estimated to be less than 0.1 s. To alleviate the time lag and pulsation of nozzle pressure, it was necessary to reduce the variation of the pulse width modulation (PWM) voltage relative to the ground velocity. The VRA system with Kalman filter would be implemented in unmanned rotorcraft for aerial application purpose. Consequently, the adaptation of Kalman filter technology enables to improve spray uniformity along the flight trajectory.

The purpose of this article is to present a comprehensive overview of the latest developments in greenhouse design to find the leading design practices that lower the carbon and energy footprint. This paper is based on a comprehensive review of existing literature regarding design trends in lighting, environmental controls, carbon dioxide supplementation, passive design features, and renewable energy for agricultural greenhouses. A systematic review of existing literature on the design trends in lighting, environmental controls, carbon dioxide supplementation, passive design features, and renewable energy options for agricultural greenhouses has been presented. This systematic review provides a platform for universal greenhouse design guidelines to help promote urban agriculture and ensure food security for cities.

Purpose: The aim of this study is to develop a small combine for harvesting miscellaneous cereal crops. Methods: A prototype small combine was designed and constructed. Its specifications and basic performance were investigated. Results: The prototype small combine for harvesting miscellaneous cereal crops was designed and constructed to reflect similar specifications as those of the conventional combine. The prototype small combine comprises a diesel engine with the rated power/speed of 22.0 kW/2,600 rpm, three-stage primary and two-stage speed range transmission shifts, and a double acting threshing part. The maximum travel speeds of the prototype combine are approximately 0.72 m/s, 2.50 m/s, 0.30 m/s at the low, high speed range shifts in the forward direction, and while traversing in the reverse direction, respectively. The minimum radius of turning was approximately 1.50 m. In a static lateral overturning test, the prototype combine overturned neither to the right nor to left on a 30° slope. The results of an oilseed rape harvesting test included the maximum operating speed of 0.32 m/s, the grain loss ratio of approximately 9.0%, and the effective field capacity of approximately 10.3 a/h. Additionally, among the outputs in grain outlet, the whole grains, damage grains, and materials other than grain (MOG) ratios accounted for 97.4%, 0.0%, and 2.6%, respectively. Conclusions: The prototype small combine for harvesting miscellaneous cereal crops indicates good driving ability and stability. The results of the oilseed rape harvesting test reveal that the harvesting performance must be enhanced such that the separating and cleaning parts are more suitable for each type of crop, thus reducing grain loss and foreign substances among the outputs in grain outlet. An improved small prototype combine could be used effectively to mechanize the harvesting of miscellaneous cereal crops in small family farms or semi-mountainous areas.

Purpose: The present study investigated the nutritional and organoleptic characteristics of two African leafy vegetables (ALVs)―jute mallow (Corchorus olitorius L) and cowpea (Vigna unguiculata)―at various drying temperatures. Methods: The thin-layer drying of cowpea leaves and jute mallow was studied at various temperatures (40-100°C) in a convective laboratory dryer, and the nutrient profiles of the dried vegetables were determined. The nutrients considered were vitamins B2 and C, and β-carotene. The level of vitamin C was determined by high-performance liquid chromatography (HPLC), whereas the levels of β-carotene and vitamin B2 were determined by titration. Results: β-carotene was the most stable nutrient, whereas vitamin C was the least stable nutrient in both cowpea leaves and jute mallow. The drying parameters―temperature and time―revealed that temperature had the most profound effect on vegetable nutrient stability. Organoleptic tests were carried out on the fresh and dried vegetable; there were no significant differences in preference between the fresh and dried ALVs (95% confidence interval). Conclusions: The present study revealed that the vegetables can be preserved by drying, and the study could be used as a guide for effective drying of those vegetables.