نشریه مکانیزاسیون کشاورزی
سال هفتم شماره 1 (بهار 1401)

Strengthening of export capacity and active presence in global markets is one of the most important and effective factor regarding continuation of economic growth. Considering that the legatum prosperity index is a measure of the competitiveness of countries in the global economy, so the present study was conducted to analysis of the effect of Iran's ranking change in the legatum prosperity index on export of Iranian agricultural machines and equipment. For this purpose, the necessary data about to export of Iranian agricultural machinery and equipment to 14 major trading partner countries along with other required information was collected during the time period of 2016-20. According to the latest ranking of legatum institute in 2020, Iran’s rank in terms of legatum prosperity index is 120 out of 167 countries. The results of estimating the gravity model showed that the decline of Iran’s rank in the legatum prosperity index has the most negative effect and Iran's membership in trade agreements with other countries (1.56) has most positive effect on export rate of Iranian agricultural machinery and equipment’s. Partners GDP (0.72) and real exchange rate (0.22) has a positive effect and per-capita GDP of partner countries (-1.79) and the geographical distance (-0.65) has a negative effect on Iran's exports. According to the results it is suggested that in order to exports increase and achieving to sustainable economic growth, the necessary measures and policies should be designed and implemented to improve Iran's position in various sub-indicators of the legatum prosperity index especially economical sub-indicators.

Long boom sprayers as efficient and high-performance machines enable farmers to carry out crop protection within a reasonable period. Despite many pieces of research, heterogeneity in spray pattern due to boom vibration remains a major challenge. In the present research, the feasibility of adjusting spray angle through pressure variation in conjunction with spray rate control using a pulse width modulation (PWM) to accomplish desired spray pattern was investigated. Using acquired data from various technical tests, a program developed via LabVIEW software to control the spray pattern along with spray rate as a function of nozzle height. The conformity of mean operational pressures and target pressures was investigated using the Kolmogorov–Smirnov Test. A similar method was used to investigate the conformity of mean operational fan angles and target fan angles. Mean differences of operational pressures were almost insignificant in the whole range of measurement height. Therefore, it can be concluded that the height factor has no significant effect on the ability of the system to obtain the target pressure. Results also indicated that mean operational pressures are in conformity with target pressures. Distribution of the operational and target fan angles was significantly difference. Considering the existence of target pressure in the system and the inability of the system in providing the target fan angle, it is concluded that nozzle performance in creation the target fan angle was not perfect.

Cultivation of corn in the form of seedlings can be considered as a solution for producing early crops, reducing production time, and saving water and various agricultural inputs. Therefore, the aim of the current research was to develop an algorithm to evaluate the uniformity of planting in the nursery with the help of image processing. In order to determine the number of seedlings, various transformations (excessive greenness, normalized intensity difference index of red and green values ​​and normalized intensity difference index of blue and green values) were evaluated. Then, by applying thresholding by Etsu method, the information of corn seedlings was separated from the background. Finally, by implementing the Freeman labeling method and the Harris method and analyzing the features of overlapping areas, an automatic algorithm was developed to count corn seedlings in these areas. The developed algorithm was evaluated online at speeds of 5, 8, 10 and 12 km/h. According to the obtained results, the best uniformity and monoculture was obtained by the transplanter at a speed of 5 km/h with a percentage of correct cultivation of 97% and the highest percentage of incorrect cultivation at a speed of 12 km/h and equal to 21%. Therefore, based on the present study, according to the obtained accuracy, the developed algorithm can be used not only to count the number of corn seedlings in the field, but also to evaluate the uniformity of planting of seedlings.

The spread of mechanical cotton harvesting can cause significant changes in the conventional cotton production process from the point of planting pattern and variety. A field experiment was conducted to evaluate the cotton picker and stripper performance as affected by in conjunction with plant density and cultivar from 2019 to 2020. The experimental design was a randomized complete block with split-split plot arranged in three replications. The cotton harvester were in two levels of spindle picker cotton (PC) and finger stripper cotton (SC) as the main plot, three cultivars as the subplot include: Macsa (V1), Golestan (V2), Hekmat (V3) and the plant density (PP1:10, PP2:13, PP3:16 plant m2) as sub-sub plot. The results showed that cotton harvester, variety and plant density had a significant effect on performance indexes of cotton harvester. The maximum effective field capacity and material capacity belonged to finger stripper harvester. The results also revealed that the PC treatment on average decreased ground loss by 38.9% and increased harvesting efficiency by 3.5% compared to SC treatment. As the plant density was increased from 10 to 16 plant m2 in SC treatment, the ground loss and stalk loss were decreased (22.3 and 50.5, respectively). The highest seed cotton yield was observed in the V2× PP2 interaction. According to our findings and based on the seed cotton yield and crop losses, application of PP2 treatment in combination with V2 and V1 treatments were seen suitable in the cotton growing regions of Fars province.

There are many losses in crop production each year, due to various reasons. The use of shadow nets in orchards is one of the protection solutions. In order to select the appropriate net, it is necessary to determine the main factors in plant growth to utilize from net benefits and prevent its adverse effects.. In general, light, temperature and humidity are three main effective factors in plant growth and development. In this research, a monitoring system was designed and built to monitor the changes in radiation, temperature and relative humidity inside and outside of the selected covered pistachio and apricot gardens. Wind velocity and direction outside the gardens were also measured. The measured data by the system related to these factors inside and outside the gardens was collected in a central server. Investigation of monthly graphs of changes in temperature, relative humidity and light received from apricot gardens in Shahroud and Pistachio gardens in Rafsanjan showed that the temperature inside the shading nets was lower than outside but there was no significant difference between the months records. For relative humidity and light factors, respectively the inside records were higher and lower than outside records. But no significant differences were observed between the months. In general, the study of changes in the mean values of the three factors of temperature, humidity and radiation in the whole period showed that the greatest effect of shading net in orchards was the reducing of the intensity of light received. When the wind velocity was high, the temperature inside and outside the shading net was closer to each other.