Wind farms begin to influence the power systems with the increasing amount of wind power penetration. The study of such influence justifies the need of a dynamic wind farm model comprising of a large number of generators, but detail models require high simulation computation time. An aggregation technique is required to reduce the model order while maintaining its accuracy. In this paper, a complete and an aggregated wind farm model with Doubly Fed Induction Generator (DFIG) are presented. Simulations have been carried out for both models and compared to demonstrate effectiveness of the aggregated model in terms of accuracy in approximation of the dynamic collective responses at the Point of Common Connection (PCC) and reduction in simulation computation time.

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The study was conducted to determine the extent of adaptation of farming practices by smallholder farmers in response to climate change in coastal regions of Bangladesh. The data were collected from 80 randomly selected smallholder farmers with the objectives to identify the adaptation of farming practices, to determine the factors those influence adaptation of farming practices and to find out the constraints faced by the farmers in adapting farming practices. The findings of the study revealed that majority (75%) of the smallholder farmers made low to medium adaptation of farming practices in response to climate change. Correlation analysis indicated that among the selected socio-economic characteristics, respondent's education, annual family income, communication exposure, agricultural training and perception of climate change showed positive and significant relationship with their adaptation of farming practices.Step-wise multiple regression analysis explored that amongst six, four independent variables finally entered into the model and contribution of these factors (education, perception, communication exposure and training) accounted for 88% of the total variation in the extent of adaptation of farming practices. It was found that majority (76%) of the smallholder farmers had faced high to medium constraints in adapting farm practices in response to climate change.

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The study was carried out mainly to evaluate the knowledge, attitude and practice (KAP) of farmers regarding nitrogen fortified organic manure. Data were collected from purposive-randomly selected 120 farmers from Kharnia, Atalia, Maguraghona unions of Dumuria upazila under Khulna district of Bangladesh through personal interview using an interview schedule during January to February, 2019. There were eleven personal socioeconomic characteristics of farmers selected for the study which were age, educational qualification, family size, farming experience, organic farming experience, annual income, farm size, organizational participation, agricultural training, cosmopolitanism, extension contact regarding nitrogen fortified organic manure, were treated as independent variables, whereas knowledge, attitude, practice (KAP) and faced problems were considered as dependent variables. Majority (65%) of the respondents had high knowledge, most of the respondents (85.8%) had medium favorable attitude and majority of the respondents (65.8%) had medium practice, respectively, regarding nitrogen fortified organic manure. 65% of the respondents encountered medium problem while preparing and applying nitrogen fortified organic manures in the crop field.  Although farmers usually use inorganic nitrogen fertilizer but they have favorable attitude regarding nitrogen fortified organic manure. On the basis of the response provided by the respondents’ positive statements ranked first and negative statements ranked second in gross considerations. The 1st position was ranked by the individual statement “N fortified organic manure is good” on the basis of obtained highest score (532), which was followed by “soil health is maintained” (2nd, score 530) and “great source of income” (3rd, score 488). Among the selected characteristics of farmers, annual income showed negative significant relationship with attitude while farm size, agricultural training showed positive significant relationship; and family size showed negative significant relationship with knowledge of farmers regarding nitrogen fortified organic manure. Cosmopolitanism and extension contact showed positive significant relationship with practice; while agricultural training showed negative significant relationship with problem of farmers regarding nitrogen fortified organic manure. Thus, the high knowledge, medium favorable attitude and medium practice should be utilized to design appropriate extension strategies for production and application of the nitrogen fortified organic manures by the farmers in their agricultural fields for crop production. The encountered problems also should be addressed properly to ensure timely mitigation. Proper measures should also be undertaken to make nitrogen fortified organic manure popular day by day.