In this paper, the optimal operation of microgrids (MGs) with thermal blocks, distributed generations (DGs), storage systems, and responsive loads is presented to achieve optimal scheduling of active, reactive, and thermal power of the mentioned elements in the day-ahead (DA) reactive power and energy market environment. The thermal block has a combined heat and power (CHP) system, a boiler, and thermally responsive loads. This scheme minimizes the difference between the total operating costs of the MG and power sources and the total revenue gained from the sale of energy and reactive power of the mentioned elements in the markets located in the MG. It is constrained by the AC power flow equations, network operation constraints, and the operating model of these elements. Furthermore, this scheme is subject to the uncertainties of energy price, load, and renewable power. In this paper, to access the optimal resistant solution against the maximum prediction error associated with the mentioned uncertainties, a robust model based on information gap decision theory (IGDT) is used. Finally, by implementing the proposed scheme on a 119-bus radial MG, the obtained numerical results confirm the ability of the scheme to simultaneously improve the economic and operational situation of the MG. The proposed scheme succeeded in improving energy cost, energy loss, voltage drop, and power factor of the distribution substation by roughly 101%, 44%, 41%, and 16% compared to power flow studies, even in the worst-case scenario caused by uncertainties.
Introduction: Due to water scarcity and increased water consumption during the past years, the importance of water in terms of transmission of diseases, as well as Iran's climate, groundwater aquifers are known as the most important resources of drinking water supply. Using the Water Quality Index (WQI) is considered as strong managerial tool for decision making in water resource management. Therefore, the aim of this study was to evaluate the quality of groundwater in Ardakan for drinking purpose using WQI. Spatial analysis was conducted with the geographic information system (GIS). Materials and Methods: This is a descriptive, cross-sectional study to investigate the quality of groundwater in Ardakan for drinking purpose. Information on total dissolved solids (TDS), total hardness, pH, electrical conductivity (EC), bicarbonate (HCO3-), chlorine (CL-), sulfate (SO42-), nitrate (NO3-), calcium (Ca2+) and magnesium (Mg2+) of 24 wells was obtained from Ardakan Health Center. The characteristics of the stations were determined using the Global Positioning System (GPS) and transmitted to the map prepared in the GIS environment. The calculated values of the WQI were zoned in the GIS environment by Inverse Distance Weighted (IDW) method. Results: Based on the WQI, well no.5 has the best quality water (17.61), which has the lowest WQI, and the highest value of WQI was obtained for well no. 20 (156.86). Conclusion: The results of the study showed that none of wells have drinkable water, 13 wells had good quality water, and 11 wells had poor quality and should be treated for drinking.
Introduction: Musculoskeletal disorders are one of the most important occupational health issues. In recent years, the rapid growth of technology and the use of computers have affected almost all office workstations. These disorders are also very common among office staff. Therefore, the present study aimed to investigate the prevalence of musculoskeletal disorders and the degree of body discomfort in the staff of the School of Public Health, Shahid Sadoughi University of Medical Sciences Yazd. Methods: This descriptive cross-sectional study was conducted on 130 office staff of Yazd School of Public Health in 2021. The inclusion criterion consisted of having at least one year of work experience and the exclusion criteria included the presence of musculoskeletal complications in different organs of the body and no history of incidents, accidents, and inherited diseases. To collect data, the Nordic questionnaire was used along with a body map (to better understand the position of the limbs) and a visual analog scale (VAS) (to show the severity of discomfort in different parts of the body). The data were analyzed using SPSS software version 22 using frequency, mean, standard deviation, and AONVA tests. Results: 108 people (83.7%) of the study population felt pain and discomfort in at least one of the 9 areas of the body during the last 12 months. The most musculoskeletal disorders was related to the low back (67.4%), neck (63.6%), and back (55%). Also, the low back waist, neck, and shoulder areas had the highest mean discomfort, respectively, and the thigh and elbow areas had the lowest mean discomfort. In the report of pain by body map, a significant relationship was observed between the variable of work experience and shoulder, thigh, and low back organs (p <0.05). A significant relationship was observed between low back pain, musculoskeletal disorders in the hands and wrists and body mass index (p <0.05). Conclusion: Due to the high prevalence of musculoskeletal disorders and the high degree of discomfort, especially in the low back and neck, it is recommended to perform educational programs, corrective exercises, and appropriate interventions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.