No abstract

Precise quantification of evaporation has a vital role in effective crop modelling, irrigation scheduling, and agricultural water management. In recent years, the data-driven models using meta-heuristics algorithms have attracted the attention of researchers worldwide. In this investigation, we have examined the performance of models employing four meta-heuristic algorithms, namely, support vector machine (SVM), random tree (RT), reduced error pruning tree (REPTree), and random subspace (RSS) for simulating daily pan evaporation (EPd) at two different locations in north India representing semi-arid climate (New Delhi) and sub-humid climate (Ludhiana). The most suitable combinations of meteorological input variables as covariates to estimate EPd were ascertained through the subset regression technique followed by sensitivity analyses. The statistical indicators such as root mean square error (RMSE), mean absolute error (MAE), Nash–Sutcliffe efficiency (NSE), Willmott index (WI), and correlation coefficient (r) followed by graphical interpretations, were utilized for model evaluation. The SVM algorithm successfully performed in reconstructing the EPd time series with acceptable statistical criteria (i.e., NSE = 0.937, 0.795; WI = 0.984, 0.943; r = 0.968, 0.902; MAE = 0.055, 0.993 mm/day; and RMSE = 0.092, 1.317 mm/day) compared with the other applied algorithms during the testing phase at the New Delhi and Ludhiana stations, respectively. This study also demonstrated and discussed the potential of meta-heuristic algorithms for producing reasonable estimates of daily evaporation using minimal meteorological input variables with applicability of the best candidate model vetted in two diverse agro-climatic settings.

Abstract:A study was conducted to investigate biometric properties of seedlings of three common varieties of onion viz. Pusa Red, 60, 70 days old). The parameters determined were weight of seedling without and with de-topping, bulb diameter, stem diameter, height, moisture content, compressive strength and coefficient of static friction. The weight of seedlings without de-topping ranged from 0.53 to 3.05 g while with de-topping ranged from 0.47 to 1.68 g for all the three cultivars. The bulb and stem diameter for all varieties ranged from 3.13 to 5.76 g for bulb and 2.44 to 4.33 g for stem whereas height varied from 14.48 cm to 34.65 cm, among all Pusa red was taller than Set-126 and Pusa Ridhi. The moisture content at different age and for all cultivars ranged from 84.89 to 91.63 % (wb). The average coefficient of static friction for mild steel (MS), aluminum and galvanized iron (GI) varied from 0.63 to 0.79. The compressive strength of bulb and stem of seedlings were 9.76 to 19.54 N for bulb and 4.08 to 8.17 N for stem respectively for 50 to 70 days seedlings. This information was not available but is critical in designing and selection of different components of onion seedling transplanter.

In this study, apple slices were dried using infrared (IR) and hot air techniques and comprehensively analyzed in terms of drying and product characteristics. The influence of IR power level (450–650 W) and hot air temperature (60–75°C) on mass transfer, color kinetics, product texture, microstructure, and rehydration characteristics was studied. The results indicated that drying time, color change, and energy requirement were lower in IR drying than in hot air drying. Moisture diffusivity was observed to increase with IR power (3.367 × 10−9–5.579 × 10−9 m2/s) and hot air temperature (1.288 × 10−9–2.387 × 10−9 m2/s). The activation energies of apple slices in IR and hot air drying were 11.94 and 21.90 kJ/mol, respectively. IR‐dried apple slices were more crispy, with a porous structure and higher rehydration ability. Experimental data were fitted to nine different thin‐layer drying and four‐color kinetic models using nonlinear regression analysis. The results of regression analysis indicated that the Midilli–Kucuk model is the best model to describe the drying behavior in both techniques. The color characteristics (L, a, and b) can be best explained by the modified color model and total color change by fraction conversion model for both IR and hot air drying of apple slices. This study revealed that IR drying of apple slices results in a better quality product in less time and energy as compared to hot air drying. Practical applications Drying is a vital food processing and preservation technique based on the principle of reducing the water content of the product. Although several drying techniques are available, there have been continuous efforts to improve drying methods in terms of energy efficiency and product quality attributes. The present work has been carried out considering the dearth of information on the influence of infrared power/intensity on the drying behavior and product quality of apple slices. Mass and color kinetics have been studied for a better understanding of the process, along with texture, microstructure, and rehydration properties. Our results showed that the process is superior, in terms of energy and product quality, as compared to other published work. It is concluded that infrared drying can be effectively used in the dehydration of apple slices on an industrial scale and can be promoted as a healthy alternative to fried snacks.

No abstract

No abstract

No abstract

The central concern of this paper is to discuss the positioning of the researcher while researching one’s own community ethnographically. It argues that insider and outsider positioning of a researcher in insider ethnographic research appears in a contextual, iterative, and emergent manner. The strategies provide space for critical self-reflexive practices in the field, thereby enhancing the quality standard. In addition, it argues that the positioning of the researcher appears while maintaining the ethical issue of confidentiality. Thus, the paper claims that it is not necessary to set the ideological frame for structuring the researchers whilst engaging in the field with particular positioning. It highlights that the defined roles of a researcher guide him/her in a way denying to engage in the field adapting the contextual phenomena, thereby creating difficulties for generating quality data.