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GNSS Baseline Configuration Based on First Order Design
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The quality of Global Navigation Satellite Systems (GNSS) networks are considerably influenced by the configuration of the observed baselines. Where, this study aims to find an optimal configuration for GNSS baselines in terms of the number and distribution  of baselines to improve the quality criteria of the GNSS networks. First order design problem (FOD) was applied in this research to optimize GNSS network baselines configuration, and based on sequential adjustment method to solve its objective functions.

FOD for optimum precision (FOD-p) was the proposed model which based on the design criteria of A-optimality and E-optimality. These design criteria were selected as objective functions of precision, which lead to a homogenous and anisotropic network, respectively  using Matlab programming language (V. 2012a). Al Ghammas Township, Al-Qadisiya city, which consists of twenty-five stations was taken as a study area in this research.

The results showed that there are 300 potential baselines for the GNSS network of the study area, which were reduced during the optimum configuration to about 70% of the total potential baselines by applying FOD-p, and there is high level of improvement in the objective functions of precision which  reached to about 90% .

 

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Publication Date
Fri Aug 16 2019
Journal Name
Canadian Journal Of Physics
Influence of the variation in the Hubbard parameter (U) on activation energies of CeO2-catalysed reactions
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Accurate description of thermodynamic, structural, and electronic properties for bulk and surfaces of ceria (CeO2) necessitates the inclusion of the Hubbard parameter (U) in the density functional theory (DFT) calculations to precisely account for the strongly correlated 4f electrons. Such treatment is a daunting task when attempting to draw a potential energy surface for CeO2-catalyzed reaction. This is due to the inconsistent change in thermo-kinetics parameters of the reaction in reference to the variation in the U values. As an illustrative example, we investigate herein the discrepancy in activation and reaction energies for steps underlying the partial and full hydrogenation of acetylene over the CeO2(111) surface. Overall, we find th

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Publication Date
Fri Dec 22 2023
Journal Name
Eastern-european Journal Of Enterprise Technologies
Evaluating the impact of structure parameters on the acoustic performance of an exhaust muffler with shells
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Recently, environmental noise has arisen from various sources, such as those from exhaust mufflers of combustion engines found in cars, trucks, or power generators, which produce significant noise during their operation. Controlling the radiated noise from these mufflers is a major factor in improving acoustic comfort and minimizing the impact on the surrounding communities. Numerous research has been presented for this reason by modification of the internal structure of the exhaust muffler. The main objective of this work is to reduce the noise level emitted from exhaust mufflers. This can be achieved by adjusting structure parameters to attenuate the surrounding environment's radiated noise. Analysis of pressure-wave propagation h

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Publication Date
Wed May 01 2024
Journal Name
Journal Of Physics: Conference Series
Studying the effect of changing optical fibers parameters on their modes properties at 1000 nm wavelength
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Abstract<p>Optical fiber technology is without a doubt one of the most significant phases of the communications revolution and is crucial to our daily lives. Using the free version (2022) of RP Fiber Calculator, the modal properties for optical fibers with core radii (1.5−7.5) μm, core index (1.44−1.48) and cladding index (1.43−1.47) have been determined at a wavelength of 1000 nm. When the fiber core’s radius is larger than its operating wavelength, multimode fibers can be created. The result is a single-mode fiber in all other cases. All of the calculated properties, it has been shown, increase with increasing core radius. The modes’ intensity profiles were displayed.</p>
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Publication Date
Sat Jan 01 2022
Journal Name
Journal Of Animal Behaviour And Biometeorology
Comprehension of the zinc chloride's ameliorative apoptotic and genotoxic effects on mice with cadmium-induced hepatotoxicity
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Publication Date
Thu Dec 01 2011
Journal Name
Iraqi Journal Of Physics
Influence of water absorption on fatigue behavior for chopped and woven-glass-fibers-reinforced PMMA denture
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The influence of fiber orientation and water absorption on fatigue crack growth resistance for cold cure acrylic (PMMA) reinforced by chopped and woven -glass-fibers were investigated. A weight of 2 g for chopped fibers and the same weight for woven -glass-fibers (one layer) were used to prepare samples. Some of these samples would storage in dry condition; the others were immersed in water for 15 days. Fatigue test was carried out. The results shows that, for PMMA, the initial bending stress for dry specimen was 3.392 N/cm2 and the number of cycles were 1364, the initial bending stress for wet samples was 4.20 N/cm2, and the number of cycles was 2411. The samples would cut in two pieces because of the cracks would propagated fast during

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Publication Date
Mon Aug 01 2022
Journal Name
Hiv Nursing
The Influence of Some Vitamins and Biochemical Parameters on Iraqi Females’ Patients with Malignant Breast Cancer"
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The Influence of Some Vitamins and Biochemical Parameters on Iraqi Females’ Patients with Malignant Breast Cancer"

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Publication Date
Wed Sep 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Comparison of Shear Bond Strength of Three Different Brackets Bonded on Zirconium Surfaces (In Vitro Study)
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Background: With the increased in the demands of adult orthodontics, the challenge of direct bonding to non-enamel surface (zirconium) had been increased. The present study was carried out to compare the shear bond strength of three different brackets (stainless steel, sapphire and composite) bonded to zirconium surface and study the mode of bond failure. Materials and methods: The sample was comprised of 30 models (8mm *6mm*1.5mm) of full contour zirconium veneers. They were divided into three groups according to the brackets type; all samples were treated first by sandblast with aluminum oxide particle 50 µm then coated by z-prime plus primer. A central incisor bracket of each group was bonded to the prepared zirconium surface with lig

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Publication Date
Mon Oct 01 2018
Journal Name
Plant Archives
Effect of adding different levels from bee pollen in diet on productive performance of broiler chickens
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This study was conducted in the poultry field of the Department of Animal Production - Faculty of Agriculture - University of Baghdad (Abu Ghraib) for the period from 28/9/2017 to 9/11/2017 for a period of six weeks (42 days), was used in the experiment 300 chick of broiler (Ross 308) one day old. The aim of this study was to effect of adding supplementing different levels of bee pollen (0, 250, 500, 750 and 1000) gm/100kg on Productive Performance. The chicks were randomly distributed in to five treatments, T1 control (without any addition), (T2, T3, T4 and T5) adding bee pollen in the diet 250, 500, 750 and 1000 gm/100kg respectively. The results showed that bee pollen in the diet level 1000 gm/100 kg led to significant increase in the we

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Publication Date
Thu Dec 01 2022
Journal Name
Journal Of Engineering
Multi-Criteria Optimization for Governmental Projects Priority Ranking Depending on Fuzzified Experts’ Opinion using Hygiene Approach
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Each organization struggles to exploit each possible opportunity for gaining success and continuing with its work carrier. In this field, organization success can be concluded by fulfilling end user requirements combined with optimizing available resources usage within a specified time and acceptable quality level to gain maximum profit. The project ranking process is governed by the multi-criteria environment, which is more difficult for the governmental organization because other organizations' main target is maximizing profit constrained with available resources. The governmental organization should consider human, social, economic and many more factors. This paper focused on building a multi-criteria optimizing proje

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Publication Date
Sat Oct 28 2023
Journal Name
Baghdad Science Journal
Impact of some environmental parameters on phytoplankton diversity in the eastern Al-Hammer marsh / southern Iraq
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Biodiversity is one of the important biological factors in determining water quality and maintaining the
ecological balance. In this study, there are 223 species of phytoplankton were identified, and they are as
follows: 88 species of Bacillariophyta and were at 44%,70 species of Chlorophyta and they were at 29 %, 39
species of Cyanophyta and they were at 16 %, 12 species of Euglenozoa and they were at 4 %, four species of
Miozoa and they were at 3 %, and, Phylum Charophyta and Ochrophyta were only eight and two species,
respectively and both of them were at 2%. The common phytoplankton recorded in the sites studied
include Nitzschia palea, Scenedesmus quadricauda, Oscillatoria princeps, and Peridinium

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