Research in Agricultural Engineering - In Press
Study on drying kinetics of Rosa flower buds using different drying methodsOriginal Paper
Hamid Reza Gazor, Omid Reza Roustapour
This study investigated the drying kinetics of Rosa flower buds (Rosa damascene Mill) under environmental conditions (shade), as well as in direct and indirect solar dryers. The effects of temperatures of 40, 50, and 60oC on the drying of the buds were also examined using a laboratory cabinet dryer. The drying rate of the Rosa flower buds was compared with various mathematical models and the parameters of these models were evaluated. Results illustrated that drying Rosa flower buds under shade required a lengthy period time of approximately 13 days. In contrast, utilizing solar dryers significantly reduced the drying period time for Rosa flower buds. Also, compared to the ambient drying method, the use of indirect solar dryers had the most substantial effect on decreasing the drying period time of the buds up to 86.6%. Furthermore, applying a temperature of 60°C in the laboratory dryer reduced the drying time of the buds by 76.2% compared to a temperature of 40°C. The Midili et al. (MDM), Page (PM) and Approximate Diffusion (ADM) models demonstrated good fit with experimental data and can be employed to represent the drying behavior of Rosa flower buds. the effective of moisture diffusivity of Rosa flower buds during drying was found to a range from 6.87×10-12 to 1.89×10-10 m².s-1 and activation energy values were determined as 65.30 and 72.80 kJ.mol-1 for buds which dried in the laboratory cabinet dryer and those dried using ambient and solar dryer methods, respectively.
Biodegradable Seedling Pots from Sawdust and Spent Mushroom CompostOriginal Paper
Francis Kumi, Joseph Conduah, Hans Murangaza, Seth Osei
Circular bioeconomy is rapidly gaining grounds in the agricultural sector with priority given to the utilization of more environmentally friendly materials for production and processing. Thus in this study, biodegradable seedling pots were developed using sawdust (SD) and spent mushroom compost (SMC) as a sustainable alternative to plastic containers. Four pots composed of SMC:SD ratios of 100:0, 70:30, 60:40, and 50:50 were developed and evaluated. Their mechanical properties, structural characteristics, water absorption capacity pots were assessed and seedlings made to grow in them to monitor growth support potential. A universal tensile test machine was used to assess the indirect tensile strength (mechanical properties) while the samples scanning electron microscope was used to examine the morphology of the samples. Also, images of seedling roots were segmented and analyzed in ImageJ and WinRHIZO softwares to determine the root system architecture. The results demonstrated that the 60:40 ratio exhibited superior performance including optimal water absorption capacity, indirect tensile strength, and structural properties. The 70:30 ratio also showed comparable tensile strength values. However, increasing SMC content in the pot improved root developments. This research presents a viable solution for converting agricultural waste into environmentally friendly seedling containers and suggest a potential option for reducing dependency on plastic pots in agriculture.
Architecture of a cyber-physical system for washing agricultural machineryOriginal Paper
Anatoliy Tryhuba, Orest Filkin, Inna Тryhuba, Andriy Tatomyr, Oksana Malanchuk
This paper presents the architecture of a cyber-physical system for automated washing of agricultural machinery, designed to enhance efficiency and intelligent control. The system includes four layers – physical, sensor, computational, and interface and integrates actuators, sensors, decision-making modules, and analytics. A Python-based simulation using Control and SimPy showed an average washing time of 10.4 minutes and 97.5% cycle initiation accuracy under critical contamination. Control was achieved via GRU prediction and PID regulation. Despite assumptions like ideal sensors and fixed conditions, the system proved feasible, with future work targeting real-world validation and digital twin development.
Effect of foam-mat drying conditions on drying rate and anthocyanin content in purple sweet potato powderOriginal Paper
Chi Dung Nguyen, Hong Van Hao, Ngoc Giau Tran, Minh Thuy Nguyen, Ngo Van Tai
The study aimed to optimize foam-mat drying parameters for producing purple-fleshed sweet potato (PFSP) powder. Egg albumin (EA) (5-15%), xanthan gum (XG) (0.1-0.5%), and drying temperature (50-70 °C) were used as independent variables for optimization via Response Surface Methodology with a Box-Behnken design. The response variables (drying rate and anthocyanin content) were assessed by 18 treatments, which included 6 central points. The analysis of variance showed a high coefficient of determination (> 88%) between predicted and experimental values across all models. Optimal foam-mat drying conditions were 11.02% EA, 0.34% XG, and 65.1 °C to achieve the highest drying rate (2.49 g water.g dry matter-1.min-1) and anthocyanin content (1.01 mg.g-1). After 3.5 hours of drying at 65.1 °C, the foam-mat dried PFSP showed a low moisture content (4.35%) and water activity (0.29). Its water solubility index, water absorption index, rehydration ratio, total polyphenols, and antioxidant activity were determined to be 56.49%, 3.55%, 3.82, 3.66 ± 0.06 mg GAE.g-1, and 58.49 ± 0.88%, respectively. Under these conditions, the powder maintained its natural beautiful and characteristic purple color. The microstructure of the foam-mat dried PFSP powder (via SEM images) was also observed.
Optimization of Irrigation requirement of Okra under Protected Cultivation using Digital LysimeterOriginal Paper
Sujitha Elango, Nagarajan Madasamy, Valliammai Annamalai, Vijayaprabhakar Arumugam
A field experiment was conducted in 2023 and 2024 to determine stage-specific crop coefficient values of okra (Abelmoschus esculentus) using the popular F1 hybrid Arka Nikita. Six evapotranspiration (ETc) based treatments were applied: five under a forced ventilated Greenhouse (T1 = 120% ETc, T2 = 100% ETc, T3 = 80% ETc, T4 = 60% ETc, T5 = 100% ETc in lysimeter) and one under open field (T6 = 100% ETc) arranged in completely randomized block design with three replications. Results showed that T2 had higher growth parameters, while T4 and T6 performed poorly. Yield was significantly higher in T2 (23.8 t/ ha in 2023 and 23.3 t/ ha in 2024), whereas T6 had a lower (9.5 t/ ha in 2023 and 8.6 t/ ha in 2024). The higher water productivity was observed in T3 (9.85 kg/ m3 in 2023 and 8.35 kg/ m3 in 2024), while T6 had the lower (1.83 kg/ m3 in 2023 and 1.35 kg/ m3 in 2024). Hence, this study recommends using stage-specific crop coefficients of 0.32, 0.63, 0.78, and 0.41 during the initial development, mid and final stages of 80% ETc to optimize water productivity and maximize yield in the greenhouse-grown okra.