Assesment of electricity excess in an isolated hybrid energy system: A case study of a Dangiwada village in rural Nepal

The increasing demand of power can be fulfilled through different architectures and electricity supply models by utilizing the available local resources. But most of the isolated energy system suffers from high energy cost and unreliable energy supply. This study identifies different electricity supply models to fulfill the dynamic demand of power in a remote area, which is analyzed in terms of cost of energy and causes for the high cost of energy. Among different factors, the presence of unusable energy (Electricity Excess) produced by the energy system during fulfillment of the demand is found to be major one cause for the high cost of energy. Further, the importance of energy storage system in isolated energy system is discussed. In this case, up to 83.4 % of electricity excess is observed, which can be utilized in different manners to reduce the total energy cost. Electricity excess profile for different energy model, their impacts and possible techniques of the solution with open views are discussed

Cost-benefit analysis and resource use efficiency of rice production system in different agriculture landscapes in Chitwan district, Nepal

The study was conducted to determine the cost-benefit analysis and resource use efficiency of the rice production system in different agriculture landscapes in the Chitwan district in 2018. The sample size of 102 rice-growing farmers out of 600 farmers, having an area of farm size greater than 0.5 hectares, was determined using Raosoft Inc. Software. A simple random sampling technique was used to collect 102 rice-growing household information in four municipalities (2 in plain and 2 in hilly area) using a semi-structured questionnaire. Data were analyzed using descriptive and statistical tools including Cobb-Douglas production function. Results showed that the use of inputs like seeds, chemical fertilizer and machinery like tractor were found significantly higher in the plain area whereas the use of inputs like labor, farmyard manure (FYM) and bullocks was found in higher in the hilly area. The costs of fertilizer, machinery, pesticide, and transportation were found higher in the plain area whereas the costs of seed, FYM, labor and bullocks were significantly higher in the hilly area. Production of rice per household was 1.87 ton whereas productivity was 5.2 ton/ha, gross profit was NRs. 41435and benefit-cost ratio was 1.59 in the plain area which was found significantly higher than the hilly area. The return to scale was found to be 0.48 which revealed that inputs used in rice production were ineffectively utilized in which organic fertilizer and labor resource were overused and seed, fertilizer, machinery and bullocks, pesticides and transportation were underused resources. The optimal allocation of these resources will increase the profitability of rice farming

Comparative Study of Different Approaches for Islanding Detection of Distributed Generation Systems

The issue of unintentional islanding in grid interconnection still remains a challenge in grid-connected, Distributed Generation System (DGS). This study discusses the general overview of popular islanding detection methods. Because of the various Distributed Generation (DG) types, their sizes connected to the distribution networks, and, due to the concern associated with out-of-phase reclosing, anti-islanding continues to be an issue, where no clear solution exists. The passive islanding detection technique is the simplest method to detect the islanding condition which compares the existing parameters of the system having some threshold values. This study first presents an auto-ground approach, which is based on the application of three-phase, short-circuit to the islanded distribution system just to reclose and re-energize the system. After that, the data mining-decision tree algorithm is implemented on a typical distribution system with multiple DGs. The results from both of the techniques have been accomplished and verified by determining the Non-Detection Zone (NDZ), which satisfies the IEEE standards of 2 s execution time. From the analysis, it is concluded that the decision tree approach is effective and highly accurate to detect the islanding state in DGs. These simulations in detail compare the old and new methods, clearly highlighting the progress in the field of islanding detection

Symptoms 6 months following SARS-CoV-2 infection in Nepali women.

In Nepal, over 1 million individuals have tested positive for SARS-CoV-2. We sought to describe the frequency of nonrecovery from this infection at 6 months and associated symptoms. We conducted a retrospective cohort study of 6142 women who had positive and negative PCR tests for this infection 6 months previously at 3 institutions in Kathmandu. In telephone interviews women provided information on 22 symptoms and their intensities, health status and history, and functional status. Of 3732 women who had tested PCR positive, 630 (16.9%) reported that they were unrecovered. These 630 unrecovered women were distinguished statistically from the 3102 recovered women by more frequent histories of allergies, rheumatoid disease, BCG immunization, Covid vaccination, strep throat and recent URIs, and both weight gain and weight losses of more than 5 kg in the 6 months following testing, and stressful events in the preceding year. Fatigue, pain, difficulty remembering, shortness of breath, heat and cold intolerance and unrefreshing sleep were reported in 41.9% to 10.5% of these 630 unrecovered women. Six months after confirmed SARS-CoV-2 infection 16.9% of Nepali women have long-COVID manifested as an immune, metabolic, and hormonal systems disruptive and dysfunction syndrome