نشریه تحقیقات سامانه ها و مکانیزاسیون کشاورزی
پیاپی 81 (بهار 1401)

Iran has special potentials in the field of medicinal plants, a field that have received less attention. The purpose of this study was to investigate the status of different stages of production of Rosa damascena and to select appropriate strategies for selecting and developing appropriate technology in the country to lower the costs of production. The research method was descriptive-analytical. The method of collecting statistics and information required for the research was using a questionnaire and face-to-face interviews with farmers and experts producing and studying medicinal plants in three provinces: Isfahan, Kerman and Fars. The total number of questionnaires (Cochran method) in this study was 60. In this research, SWOT analysis model was used to investigate the mechanization situation in different stages of medicinal plant production Factors such as strength, weakness, opportunity and threat have been identified and analyzed in the matrix. Based on the research results, in the evaluation matrix of internal factors (weakness and strength), the sum of the final score was 2.75, which showed that the strengths were higher than the weaknesses. Also, the matrix of external factors (threat and opportunity) with a total score of 2.83 showed that in the current situation, it was possible to show an appropriate strategic response to threats by strengthening opportunities. Therefore, aggressive strategy (SO) was found the best strategy to move towards improving and developing mechanization in Rosa damascena farms in those provinces. Top strategies were also identified through quantitative strategic planning matrix or QSPM in offensive strategy.

experiments were conducted on a stationary four-stroke, naturally aspirated, water-cooled, single-cylinder, compression ignition engine to study the effects of blending CNG with neat diesel in dual-fuel operational mode and the variation in engine coolant temperature on performance parameters. For this study, factorial experiments in the form of a randomized complete block design with three replications were used to analyze the statistical status of the data. The studied parameters were fuel ratio, engine speeds and coolant temperatures. All experiments were conducted at the governor control mode. The results showed that, torque, brake power and brake mean effective pressure (BMEP) in diesel-CNG dual-fuel mode at all engine speeds significantly increased compared to pure diesel. At low engine speeds, increasing the coolant temperature reduced the brake specific fuel consumption (BSFC) and brake specific energy consumption (BSEC). Also, in the diesel-CNG dual-fuel mode compared to the engine with baseline diesel fuel, BSFC and BSEC were significantly lower. Brake thermal efficiency (BTE) also showed a significant increase at high speeds and when using dual-fuel operational mode. However, raising the coolant temperature increased the BTE. When using the engine in dual-fuel mode and increasing the temperature of the coolant, the volumetric efficiency showed a significant reduction.  Furthermore, raising the coolant temperature diminished the volumetric efficiency. Overall, it can be stated that the use of a diesel-CNG dual-fuel mode with a coolant temperature of 60 degrees Celsius at entire engine speeds has the best outputs on the performance and combustion characteristics of the engine.

Sesame oil which is one of the most popular and expensive edible oils, is prone to adulteration. High price of Sesame oil has motivated adulterers to mix the high-quality Sesame oil with low-quality, less expensive vegetable oils. In this study, the fatty-acid profiles of sesame, rapeseed, sunflower oil samples as well as their mixtures (0, 5, 10, 20, 30, 40 and 50% levels) were determined using Gas Chromatography. Also, Machine olfaction system containing 10 MOS sensors was utilized for detection experiments. Sensor response patterns were used for analyzing and recognizing pattern of electronic-nose signals using multivariate data analysis, including Principal Component Analysis (PCA), Linear Discriminant Analyses (LDA), Partial Least Squares (PLS), K-Nearest Neighbors (KNN) and Support Vector Machine (SVM). Results of the SVM with RFB kernel in C-SVM method had the highest classification accuracy. The accuracy of training and validation were 96.34 and 90.56%, respectively, and next were LDA and KNN models with classification accuracies of 92.30% and 89.94%, respectively. In the light of these results, the proposed models along with the measurement system represent excellent tools for the detection of sesame seed oil adulteration with cheaper vegetable oils.

The purpose of this study is to introduce the most important challenges in advancing agricultural development in Guilan province. For this purpose, hierarchical analysis process was used to identify and rank the challenges of the agricultural sector of Guilan province. In this regard, six effective criteria along with 21 sub-criteria were considered. To determine the weight of criteria and sub-criteria, questionnaires based on pairwise comparisons were prepared and experts from Ministry of Agriculture Jihad of Guilan province were questioned to complete the questionnaires and the Expert Choice software was used to perform the calculations. According to the results, criteria of managerial challenges (0.368), fragmentation of land (0.229), lack of conversion and complementary industries and specialized and skilled human labor (0.155), resource limitation and land use change (0.126), low level of mechanization in the agricultural sector (0.076) and single crop cultivation and uncontrolled import of agricultural products (0.047) were ranked, respectively. Also inadequate use of inadequate resources and investments (0.157), failure to use supportive and credit policies (0.121) and non-payment of subsidies as a percentage of premiums to all insurers equally and irresponsible view of government and insurers on agricultural insurance (0.085), are three important sub-criteria with respect to the maximum weight obtained.

This study aimed to investigate and compare the environmental damage of raw sugar production in the cultivation and industry of Khuzestan province under a conventional linear framework and a circular bioeconomy perspective. The purpose of transition from production systems under linear economy to circular bioeconomy is to eliminate waste, increase the efficiency of materials and energy, and the production of biodiversity products to increase the sustainability of production systems, including food production systems. This study showed that the production per ton of raw sugar under the framework of linear economy leads to a loss of 167.41 Pt, which production and combustion of natural gas in sugarcane processing have the largest share in causing this damage. In comparison, the results of this study showed that the transition from a linear economy to a circular bioeconomy in which molasses and bagasse as the two major wastes of the sugar industry are converted into alcohol and fuel, respectively, resulted in a 193% reduction in total environmental damage. This result emphasizes that sugar production under the circular bioeconomy not only is a viable solution for existing waste management but also significantly reduces the environmental damage caused by sugarcane production and processing.

There is no unique method for evaluating different sprayer technologies. Existing methods have advantages and limitations that should be considered. The purpose of this study is to introduce a test method to evaluate the ULV sprayers that can be installed on the back of the trucks, which is often are used to fight invading pests, especially desert locusts. The FAO minimum requirements guideline was used to provide a test method to evaluate the performance of the ULV sprayers. Droplet size, transverse distribution and spray height of three sprayer models named ULV 3, ULV 3 Plus and ULV 5 which use atomizers with different technologies, were evaluated and spraying patterns were drawn. Results indicated that the maximum working pressure was 5 Bar and the maximum flow rate was 1.83 liters per minute at the pressure of 0.5 Bar. Numerical and volumetric median diameters were measured using water-sensitive papers and were reported smaller than 30 and 60 microns, respectively. The ULV 3 Plus sprayer which uses electrical and pneumatic power had the best performance by producing droplets with a numerical median diameter of 28 µm and a volumetric median diameter of 51 µm. Due to the limitations of this evaluating method, it is suggested that new technologies such as the use of laser light scattering or high-speed cameras replace the measurement by the water sensitive papers.