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joe-2065
Application of Wavelet Packet and S Transforms for Differential Protection of Power Transformer
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The differential protection of power transformers appears to be more difficult than any type of protection for any other part or element in a power system. Such difficulties arise from the existence of the magnetizing inrush phenomenon. Therefore, it is necessary to recognize between inrush current and the current arise from internal faults. In this paper, two approaches based on wavelet packet transform (WPT) and S-transform (ST) are applied to recognize different types of currents following in the transformer. In WPT approach, the selection of optimal mother wavelet and the optimal number of resolution is carried out using minimum description length (MDL) criteria before taking the decision for the extraction features from the WPT tree. In ST approach,
the spectral energy index and the standard deviation (STD) are calculated from the S-matrix obtained by discrete S-transform. The two approaches are tested for generating a trip signal and disconnecting the transformer supply experimentally using 1KVA, 220/110V, 50Hz, ∆ / Y threephase transformer. The experimental results show that the trip signal is initiated faster in WPT approach while the transformer is disconnected from the supply after a delay of 10-15msec in the
two approaches due to computer interface and the relay circuit used.

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Publication Date
Wed Mar 24 2021
Journal Name
Journal Of Research In Medical And Dental Science
Efficacy of Oregano Essential Oil Mouthwash in Reducing Oral Halitosis: A Randomized, Double-Blind Clinical Trial
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Efficacy of Oregano Essential Oil Mouthwash in Reducing Oral Halitosis: A Randomized, Double-Blind Clinical Trial, Mohamed Saeed M Ali, Ayser Najah Mohammed*

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Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
The impact of monetary policy variables inflation in Algeria: standard study using self regression time gaps
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                In the past years, the Algerian Economy has witnessed various monetary developments characterized by different monetary and banking reforms aimed by monetary authorities to achieve monetary stability and driving overall growth. It should be noted that there is evidence to initiate fundamental changes on the basis of which new monetary, financing and banking policy mechanisms must be formulated in Algeria by enhancing the pursuit of reforming the monetary system, in order to improve monetary and economic indicators.

                The study a

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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
Sun Mar 01 2020
Journal Name
Astrophysics And Space Science
The compound stream event of March 20-25, 2011 as measured by the STEREO B spacecraft
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Abstract<p>The interaction of interplanetary coronal mass ejections (ICME) with each other and with co-rotating interaction regions (CIR) changes their configuration, dynamics, magnetic field and plasma characteristics and can make space weather forecasting difficult. During the period of March 20–25, 2011, the Solar Terrestrial Relation Observatory (<italic>STEREO</italic> B) encountered a compound stream containing several interacting structures. Our analysis suggests that the stream consists of two ICMEs followed by an embedded ICME/CIR. The sudden appearance of the third ICME within the fast wind side of the CIR causes the proton temperature(<inline-formula><alternatives><tex-math></tex-math></alternatives></inline-formula></p> ... Show More
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Publication Date
Fri Jan 01 2021
Journal Name
Webology
The role of change management in achieving competetive advantage a case study in diyala state company
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The research aims to test the correlation relationships between wise leadership, and the business model, and to demonstrate its influence (wise leadership) on the business model. Therefore, two main hypotheses were put forward. The research was applied to a sample consisting of (87) managers and deputy managers, some of them are members on the board of directors of the researched company. The questionnaire was adopted as a basic tool for collecting data, in addition to personal interviews. A number of statistical methods were used to analyze the data and obtain results. The researcher showed a set of results, including: There is a significant correlation between wise leadership and business model. There is an influence of wise leadership on

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Publication Date
Sat Aug 01 2015
Journal Name
Plant Disease
First Report of the Cereal Cyst Nematode <i>Heterodera filipjevi</i> on Winter Wheat in Montana
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Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Engineering
Aspects of General & Secondary Indicators that form a Local System to assist Sustainability Verification in Buildings
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The research focuses on how to reach a mechanism that assists experts, engineers, and others in the architectural & engineering project to verify the co-existence of values and sustainability constituents in it. Research problem shows a clear lack, locally, in the interest to establish a value system and a list that cares about comprehending building components whether considering sustainable building criteria. Hypothesis shows that in order to head towards the applicable sustainable approach of buildings, then a local assessment system should be established to evaluate buildings during its life cycle, and from which buildings would be categorized as sustainable or not. Research aims at establishing main and general

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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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Publication Date
Sun Mar 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Spectral fluctuations in <sup>24</sup>Mg nucleus using the framework of the nuclear shell model
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Abstract<p>Random matrix theory is used to study the chaotic properties in nuclear energy spectrum of the <sup>24</sup>Mg nucleus. The excitation energies (which are the main object of this study) are obtained via performing shell model calculations using the OXBASH computer code together with an effective interaction of Wildenthal (W) in the isospin formalism. The <sup>24</sup>Mg nucleus is assumed to have an inert <sup>16</sup>O core with 8 nucleons (4protons and 4neutrons) move in the 1d<sub>5/2</sub>, 2s<sub>1/2</sub> and 1d<sub>3/2</sub> orbitals. The spectral fluctuations are studied by two statistical measures: the nearest neighb</p> ... Show More
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Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Study The Influence of Forming Conditions Like Deformation Speed on Void Closure in Open Die Forging
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This paper presents an investigation to the effect of the forming speed on healing voids that inhabit at various size in an ingot. The study was performed by using finite element method with bilinear isotropic material option, circular type voids were considered. The closure index was able to predict the minimum press force necessary to consolidate voids and the reduction. The simulation was carried out, on circular cross-section lead specials containing a central void of different size. At a time with a flat die, different ratio of inside to outside radius was taken with different speed to find the best result of void closure.

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