Preferred Language
Articles
/
bhbxBIcBVTCNdQwC_C1O
Photovoltaic system DC series arc fault: a case study
...Show More Authors

<p>Photovoltaic (PV) systems are becoming increasingly popular; however, arc faults on the direct current (DC) side are becoming more widespread as a result of the effects of aging as well as the trend toward higher DC voltage levels, posing severe risk to human safety and system stability. The parallel arc faults present higher level of current as compared with the series arc faults, making it more difficult to spot the series arc. In this paper and for the aim of condition monitoring, the features of a DC series arc fault are analyzed by analysing the arc features, performing model’s simulation in PSCAD, and carrying out experimental studies. Various arc models are simulated and investigated; for low current arcs, the heuristic model is used where a set of parameters established. Moreover, the heuristic model’s simulated arc has been shown to be compatible with the experimental data. The features of arc noise in the electrode separation region and steady-arcing states with varied gap widths are investigated. It has been discovered that after an arc fault occurs, arc noise increases, notably in the frequency range below 50 kHz; where this property is useful for detecting DC series arc faults. Besides that, variations in air gap width are more sensitive to frequencies under 5 kHz.</p>

Scopus Crossref
View Publication
Publication Date
Wed Aug 30 2023
Journal Name
Al-kindy College Medical Journal
Comparative Study between RIPASA Scoring System and ALVARADO Scoring System in Diagnosing Acute Appendicitis in Adults
...Show More Authors

Background: Acute appendicitis is regarded as one of the most common inflammation that needs surgical intervention. Different scoring systems have been used for diagnosing of acute appendicitis. ALVARADO score is one of the most widely used score in diagnosing of acute appendicitis, but the accuracy of the latter is insufficiently low in Middle-East patients. Thus a new scoring system called RIPASA score has been designed for diagnosing of acute appendicitis in those patients. The aim of this study is to use RIPASA score and compare its result with ALVARADO score in diagnosing of acute appendicitis.

Subjects and Methods: The study includes 200 patients with symptoms and signs of

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Tue May 09 2017
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
TIME MANAGEMENT AND WORK PRESSURE AND THEIR RELATIONSHIP TO ADMINISTRATIVE LEADERSHIP/ A CASE STUDY AT THE HIGHER INSTITUTE FOR ADMINISTRATIVE DEVELOPMENT OF SECURITY AND ADMINISRATIVE: TIME MANAGEMENT AND WORK PRESSURE AND THEIR RELATIONSHIP TO ADMINISTRATIVE LEADERSHIP/ A CASE STUDY AT THE HIGHER INSTITUTE FOR ADMINISTRATIVE DEVELOPMENT OF SECURITY AND ADMINISRATIVE
...Show More Authors

The research aims to determine the strength of the relationship between time management and work pressure and administrative leadership, where he was taken a sample of (47) of the administrative leadership at the Higher Institute of security and administrative development in the Ministry of Interior was used questionnaire as a key tool in collecting data and information and analyzed the answers to the sample surveyed by using Statistical program (spss) in the arithmetic mean of the calculation and test (t) and the correlation coefficient, the research found the most important results: the existence of significant moral positive relationship between both time management and work pressure and administrative leadership, the leadership of th

... Show More
View Publication Preview PDF
Publication Date
Mon Aug 01 2022
Journal Name
Communications In Mathematical Biology And Neuroscience
Stability analysis of a competitive ecological system in a polluted environment
...Show More Authors

The interplay of species in a polluted environment is one of the most critical aspects of the ecosystem. This paper explores the dynamics of the two-species Lokta–Volterra competition model. According to the type I functional response, one species is affected by environmental pollution. Whilst the other degrades the toxin according to the type II functional response. All equilibrium points of the system are located, with their local and global stability being assessed. A numerical simulation examination is carried out to confirm the theoretical results. These results illustrate that competition and pollution can significantly change the coexistence and extinction of each species.

View Publication Preview PDF
Scopus (15)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Tue Nov 01 2022
Journal Name
Iraqi Journal Of Applied Physics
Highly-Pure Nanostructured Metal Oxide Multilayer Structure Prepared by DC Reactive Magnetron Sputtering Technique
...Show More Authors

In this work, metal oxides nanostructures, mainly, copper oxide (CuO), nickel oxide (NiO), titanium dioxide (TiO2), and multilayer structure were synthesized by dc reactive magnetron sputtering technique. The structural purity and nanoparticle size of the prepared nanostructures were determined. The individual metal oxide samples (CuO, NiO and TiO2) showed high structural purity and minimum particle sizes of 34, 44, 61 nm, respectively. As well, the multilayer structure showed high structural purity as no elements or compounds other than the three oxides were founds in the final sample while the minimum particle size was 18 nm. This reduction in nanoparticle size can be considered as an advantage for the dc reactive magnetron sputtering tec

... Show More
View Publication Preview PDF
Publication Date
Mon Aug 04 2014
Journal Name
Photonic Sensors
Crystalline structure and surface morphology of tin oxide films grown by DC reactive sputtering
...Show More Authors

View Publication
Scopus (9)
Crossref (6)
Scopus Crossref
Publication Date
Mon Dec 01 2014
Journal Name
Photonic Sensors
Crystalline Structure and Surface Morphology of Tin Oxide Films Grown by DC Reactive Sputtering
...Show More Authors

Abstract: Tin oxide thin films were deposited by direct current (DC) reactive sputtering at gas pressures of 0.015 mbar – 0.15 mbar. The crystalline structure and surface morphology of the prepared SnO2 films were introduced by X-ray diffraction (XRD) and atomic force microscopy (AFM). These films showed preferred orientation in the (110) plane. Due to AFM micrographs, the grain size increased non-uniformly as the working gas pressure increased.

Preview PDF
Publication Date
Wed Sep 02 2020
Journal Name
Iraqi Journal Of Applied Physics
Heterojunction Solar Cell Based on Highly-Pure Nanopowders Prepared by DC Reactive Magnetron Sputtering
...Show More Authors

In this work, a novel design for the NiO/TiO2 heterojunction solar cells is presented. Highly-pure nanopowders prepared by dc reactive magnetron sputtering technique were used to form the heterojunctions. The electrical characteristics of the proposed design were compared to those of a conventional thin film heterojunction design prepared by the same technique. A higher efficiency of 300% was achieved by the proposed design. This attempt can be considered as the first to fabricate solar cells from highly-pure nanopowders of two different semiconductors.

View Publication Preview PDF
Publication Date
Thu Jul 09 2020
Journal Name
Agrosystems, Geosciences & Environment
Yield and quality of three potato cultivars under series of nitrogen rates
...Show More Authors

Undesirable growth of potato (Solanum tuberosum L.) crop under an excessive N fertilizer application is the main obstacle presently. This research was conducted to investigate the response of different potato cultivars; Russet Burbank, Shepody, and Superior, and its qualitative characteristics under a series of N rates. Six rates of N fertilization (0–280 kg ha−1) were applied on 11 sites in a randomized complete block design, with four replications. Sites with ≥30 g kg−1 of soil organic matter (OM) produced total tuber yield, marketable yield, and tuber weight per plant 39.5, 45.2, and 54.9%, respectively, higher than sites with ≤30 g kg−1 of OM. Tubers specific gravity increased by 0.18% in the sites with ≥30 g kg−1 of OM.

... Show More
View Publication
Publication Date
Sat Jan 13 2018
Journal Name
Journal Of Engineering
Producing Coordinate Time Series for Iraq's CORS Site for Detection Geophysical Phenomena
...Show More Authors

Global Navigation Satellite Systems (GNSS) have become an integral part of wide range of applications. One of these applications of GNSS is implementation of the cellular phone to locate the position of users and this technology has been employed in social media applications. Moreover, GNSS have been effectively employed in transportation, GIS, mobile satellite communications, and etc. On the other hand, the geomatics sciences use the GNSS for many practical and scientific applications such as surveying and mapping and monitoring, etc.

In this study, the GNSS raw data of ISER CORS, which is located in the North of Iraq, are processed and analyzed to build up coordinate time series for the purpose of detection the

... Show More
View Publication Preview PDF
Publication Date
Tue Jun 01 2021
Journal Name
Int. J. Nonlinear Anal. Appl.
Time series analysis of the number of covid-19 deaths in Iraq
...Show More Authors

Preview PDF
Scopus (2)
Scopus