This paper aims to improve the voltage profile using the Static Synchronous Compensator (STATCOM) in the power system in the Kurdistan Region for all weak buses. Power System Simulation studied it for Engineers (PSS\E) software version 33.0 to apply the Newton-Raphson (NR) method. All bus voltages were recorded and compared with the Kurdistan region grid index (0.95≤V ≤1.05), simulating the power system and finding the optimal size and suitable location of Static Synchronous Compensator (STATCOM)for bus voltage improvement at the weakest buses. It shows that Soran and New Koya substations are the best placement for adding STATCOM with the sizes 20 MVAR and 40 MVAR. After adding STATCOM with the sizes [20MVAR and 40MVAR] at Soran to the test, it is seen that the total average change in voltage profile for the system improved results in about 17.34 % in average per unit change for the 28 weakest buses, which provides a good improvement in stability. Also, the system’s total active power loss reduced from 123.8 MW without STATCOM to 102.8 MW with STATCOM. The results are encouraging for applying the approach to the power system. This approach stands out due to all bus voltages are within acceptable ranges.
The earth's surface comprises different kinds of land cover, water resources, and soil, which create environmental factors for varied animals, plants, and humans. Knowing the significant effects of land cover is crucial for long-term development, climate change modeling, and preserving ecosystems. In this research, the Google Earth Engine platform and freely available Landsat imagery were used to investigate the impact of the expansion and degradation in urbanized areas, watersheds, and vegetative cover on the land surface temperature in Baghdad from 2004 to 2021. Land cover indices such as the Normalized Difference Vegetation Index, Normalized Difference Water Index, and Normalized Difference Built-up Index (NDVI, NDWI, an
... Show MoreThe effective insulation design of the stress grading (SG) system in form-wound stator coils is essential for preventing partial discharges and excessive heat generation under pulse-width modulation excitation. This paper proposes a method to find the optimal insulation design of the SG system aimed at reducing the dielectric and thermal stresses in the machine coil. The non-uniform transmission line model is used to predict the voltage propagation along the overhang, SG, and slot regions considering the variation in the physical properties of the insulation layers. The machine coil parameters for different insulation materials are calculated by using the finite element method. Two optimization algorithms, fmincon and particle swarm optimiz
... Show MoreMassive multiple-input multiple-output (massive-MIMO) is a promising technology for next generation wireless communications systems due to its capability to increase the data rate and meet the enormous ongoing data traffic explosion. However, in non-reciprocal channels, such as those encountered in frequency division duplex (FDD) systems, channel state information (CSI) estimation using downlink (DL) training sequence is to date very challenging issue, especially when the channel exhibits a shorter coherence time. In particular, the availability of sufficiently accurate CSI at the base transceiver station (BTS) allows an efficient precoding design in the DL transmission to be achieved, and thus, reliable communication systems can be obtaine
... Show MoreIn this study, the flexural performance of a new composite beam–slab system filled with concrete material was investigated, where this system was mainly prepared from lightweight cold-formed steel sections of a beam and a deck slab for carrying heavy floor loads as another concept of a conventional composite system with a lower cost impact. For this purpose, seven samples of a profile steel sheet–dry board deck slab (PSSDB/PDS) carried by a steel cold-formed C-purlins beam (CB) were prepared and named “composite CBPDS specimen”, which were tested under a static bending load. Specifically, the effects of the profile steel sheet (PSS) direction (parallel or perpendicular to the span of the specimen) using different C-purlins c
... Show MoreAnger is one of the problems of scientific importance that psychologists and education scientists are interested in, especially societies and educational environments, because if a child’s anger continues to develop into violence, then it becomes an unusual behavior, and an indication of the child's lack of adaptation to his family and his environment (Moses, 2013: 4) &n
... Show MoreA simple, rapid and sensitive spectrophotometirc method for the determination of trace amounts of promethazine hydrochloride in the aqueous solution is described. The method is based on the complexation of promethazine hydrochloride with In (III) in the presence of sodium hydroxide to form an soluble product with maximum absorption at 304nm. Beer’s law is obeyed over the concentration range of (2- 20μg/ml) with molar absorptivity of (1.92× 103 L.mol-1 .cm -1 ). The optimum conditions for all development are described and the proposed method has been successfully applied for the determination of promethazine hydrochloride in bulk drug.
The current study, performed during the period from February 2021 to June 2022 at the University of Thi- Qar/ College of Education for Pure Sciences, and aimed to follow the changes in external morphological features at different Embryonic developmental stages in pregnant rats treated with different doses of amlodipine. Usage In this study, 18 pregnant rats were randomly divided into three groups, each with six pregnant rats. Each group received different concentrations of amlodipine (0.3, 0.5) in oral doses until the 20th day of gestation, while the control group was injected with 0.9% normal saline. Teratomas are bizarre tumors derived from embryonic tissue that are normally found only in the gonadal and sacral regions of adults. Primary
... Show MoreSalivary peroxidases have biological functions of particular importance to oral health. The aim of this paper is to shed the light on saliva and serum total peroxidases activity as well as the activity of each of salivary peroxidase (SPO) and myeloperoxidase (MPO) in patients with oral tumors. The studied participants were divided into two groups: the first group included 18 oral squamous cell carcinoma patients and 20 age and gender-matched healthy controls while the second group consisted of 20 oral ossifying fibroma patients and 23 age and gender-matched healthy controls. Total peroxidases activity was determined, and its specific activity was calculated in serum and whole mixed saliva as well as in the supernatant and pellet fractions
... Show MorePrevious data indicated the effectiveness of silibinin as intraocular pressure (IOP) - lowering agent. The present study was performed to evaluate the interaction of silibinin with pilocarpine or cyclopentolate in lowering IOP in normotensive rabbits. The effects of topically instilled silibinin hemisuccinate solution (0.75%) alone or adjunctly combined with 2% pilocarpine or 1% cyclopentolate on the IOP of normotensive rabbits were evaluated using indentation tonometry. The results showed that 0.75% solution of silibinin was found more potent than pilocarpine (2% drops) in lowering IOP of normotensive rabbits, while their combination results in longer duration of action. Moreover, the elevated IOP values produced by cyclopentolate
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