Nowadays power systems are huge networks that consist of electrical energy sources, static and lumped load components, connected over long distances by A.C. transmission lines. Voltage improvement is an important aspect of the power system. If the issue is not dealt with properly, may lead to voltage collapse. In this paper, HVDC links/bipolar connections were inserted in a power system in order to improve the voltage profile. The load flow was simulated by Electrical Transient Analyzer Program (ETAP.16) program in which Newton- Raphson method is used. The load flow simulation studies show a significant enhancement of the power system performance after applying HVDC links on Kurdistan power systems. Th
... Show MoreBackground: Little is known about asymmetry of children's dental arches, the purpose of this study was to verify the presence of asymmetry of dental arches among Iraqi children in the mixed dentition stage. Materials and methods: The sample included 52 pairs of dental casts, 27 pairs belong to males and 25 pairs for females. Three linear distances were utilized on each side on the dental arch: Incisal-canine distance, canine-molar distance and incisal-molar distance, which represent the dental arch segmental measurements using the digital sliding calipers, which is accurate up to 0.02 mm. Results: No significant sides' differences with high correlation coefficient were found between the right and left incisal-canine, canine-molar and in
... Show MoreBackground: Feeding is a complicated process that involves the coordination of cardiovascular, respiratory, gastrointestinal (GI), and oropharyngeal mechanisms, with support from the musculoskeletal and craniofacial systems. The practice of feeding could be correlated with eruption stage and nutritional status in infants. Aim of the study: This study aimed to assess the relation of feeding patterns to a selected oral variable (stage of the eruption of primary teeth) and growth parameters among clinically healthy infants. Subjects and Methods: A cross-sectional comparative study on a sample of (300) infants aged between 6 and 18 months was performed in Karbala City, Iraq. The feeding pattern was investigated using an information sheet ans
... Show MoreIn this paper, an ecological model with stage-structure in prey population, fear, anti-predator and harvesting are suggested. Lotka-Volterra and Holling type II functional responses have been assumed to describe the feeding processes . The local and global stability of steady points of this model are established. Finally, the global dynamics are studied numerically to investigate the influence of the parameters on the solutions of the system, especially the effect of fear and anti-predation.
To ascertain the stability or instability of time series, three versions of the model proposed by Dickie-Voller were used in this paper. The aim of this study is to explain the extent of the impact of some economic variables such as the supply of money, gross domestic product, national income, after reaching the stability of these variables. The results show that the variable money supply, the GDP variable, and the exchange rate variable were all stable at the level of the first difference in the time series. This means that the series is an integrated first-class series. Hence, the gross fixed capital formation variable, the variable national income, and the variable interest rate
... Show MoreIn this study, the harvest of maize silage with the cross double row sowing method were tested with a single row disc silage machine in two different PTO applications (540 and 540E min-1) and at two different working speeds v1, v2 (1.8 and 2.5 km h-1). The possibilities of harvesting with a single row machine were revealed, and performance characteristics such as hourly fuel consumption, field-product fuel consumption and PTO power consumption were determined in the trials. The best results in terms of hourly fuel consumption and PTO power consumption were determined in the 540E PTO application and V1 working speed. When the fuel consumption of the field-product is evaluated, it is obtained with V2 working speed and 540E PTO application. As
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