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The spatial extent of polycyclic aromatic hydrocarbons emission in the Herbig star HD 179218
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Aim. We investigate, in the mid-infrared, the spatial properties of the polycyclic aromatic hydrocarbons (PAHs) emission in the disk of HD 179218, an intermediate-mass Herbig star at ~300 pc.

Methods. We obtained mid-infrared images in the PAH-1, PAH-2 and Si-6 filters centered at 8.6, 11.3, and 12.5 μm, and N-band low-resolution spectra using CanariCam on the 10-m Gran Telescopio Canarias (GTC). We compared the point spread function (PSF) profiles measured in the PAH filters to the profile derived in the Si-6 filter, where the thermal continuum emission dominates. We performed radiative transfer modeling of the spectral energy distribution (SED) and produced synthetic images in the three filters to investigate different spatial scenarios.

Results. Our data show that the disk emission is spatially resolved in the PAH-1 and PAH-2 filters, while unresolved in the Si-6 filter. Thanks to very good observing conditions, an average full width at half maximum (FWHM) of 0.232′′, 0.280′′ and 0.293′′ is measured in the three filters, respectively. Gaussian disk fitting and quadratic subtraction of the science and calibrator PSFs suggests a lower-limit characteristic angular diameter of the emission of ~100 mas, or ~30 au. The photometric and spectroscopic results are compatible with previous findings. Our radiative transfer (RT) modeling of the continuum suggests that the resolved emission should result from PAH molecules on the disk atmosphere being UV-excited by the central star. Simple geometrical models of the PAH component compared to the underlying continuum point to a PAH emission uniformly extended out to the physical limits of the disk model. Furthermore, our RT best model of the continuum requires a negative exponent of the surface density power-law, in contrast with earlier modeling pointing to a positive exponent.

Conclusions. We have spatially resolved – for the first time to our knowledge – the PAHs emission in the disk of HD 179218 and set constraints on its spatial extent. Based on spatial and spectroscopic considerations as well as on qualitative comparison with IRS 48 and HD 97048, we favor a scenario in which PAHs extend out to large radii across the flared disk surface and are at the same time predominantly in an ionized charge state due to the strong UV radiation field of the 180 L central star.

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Publication Date
Fri Sep 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
Choosing the best method for estimating the survival function of inverse Gompertz distribution by using Integral mean squares error (IMSE)
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In this research , we study the inverse Gompertz distribution (IG) and estimate the  survival function of the distribution , and the survival function was evaluated using three methods (the Maximum likelihood, least squares, and percentiles estimators) and choosing the best method estimation ,as it was found that the best method for estimating the survival function is the squares-least method because it has the lowest IMSE and for all sample sizes

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Publication Date
Mon Jan 28 2019
Journal Name
Iraqi Journal Of Science
Preview on the demarcation process of the maritime border between Iraq and Kuwait by using GIS and satellite image (landsat8)
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The demarcation in general and maritime borders in particular is an important process between any two states to define their respective regional Borders and their economic resources. This research is focused on the way in which demarcation took place between Iraq's maritime borders on the one hand and the Kuwaiti side on the other. Through satellite technology (Landsat8) and GIS can be identified the area and how the demarcation was done. The most important in addition, positive points of the demarcation have been explained. It was given a full description of the importance of the economic zone and Highlighting Iraq's most important marine facilities. More than one map of Iraq can be integrated and redesigned by GIS. This work has been t

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Publication Date
Sat Feb 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Application Effect of the Conflict Management Strategies On Increasing Workers Productivity at the Electricity Company (IGEC) (Field Study Irbid Governorate)
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Research aimed to explore the Application Effect of the Conflict Management Strategies by the managements to solve conflict between and inside the conflicted parties within (IGEC) to increase the productivity of the workers. To collect data, 110 questioners had been distributed among managers and heads of departments of all managerial levels, 102 answered questioners regained, 5 of them were disqualify for statistical analytic, only 97 were taking in consideration   for statistical analysis presenting 93% of the retained number.

SPSS Program supported with a group of statistical tools, had been used for analysis purposes such as Kronbach Alpha test to assure the validity & stability of the t

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Publication Date
Fri Nov 24 2023
Journal Name
Iraqi Journal Of Science
Monte Carlo Simulation of the Effective Solid Angle and the HPGe Response to Different Mono-Energetic Protons from Extended Source
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A program using Mont Carlo techniques has been written to calculate the effective solid angle of the detection system and simulate the response of the HPGe to mono-energetic protons from an extend source. It has been found that the fraction of the protons which leave through the cylindrical surface and deposit only part of their kinetic energy in the crystal increases with proton energy and the consequent increase in their range.

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Publication Date
Mon Feb 13 2023
Journal Name
Journal Of Educational And Psychological Researches
A Proposed Strategy to Develop Postgraduate Studies at King Khalid University to Support the Achievement of the Kingdom's 2030 Vision
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Abstract

The aim of this research is to formulate a proposed strategy for developing graduate studies at King Khalid University to support the achievement of the Kingdom's vision (2030). The research used the descriptive survey approach. The research community consisted of all graduate students at King Khalid University. The research was conducted on a random sample included (623) Male and female students, this research relied on the questionnaire as the main tool for collecting its data. The results revealed that the research sample believes that all the proposals included in this research are very important for the development of postgraduate studies at King Khalid University to support the achievement of the K

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Publication Date
Tue Jan 30 2024
Journal Name
International Journal Of Engineering Pedagogy (ijep)
The Impact of Two Proposed Strategies Based on Active Learning on Students' Achievement at the Computer and Their Social Intelligence
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Active learning is a teaching method that involves students actively participating in activities, exercises, and projects within a rich and diverse educational environment. The teacher plays a role in encouraging students to take responsibility for their own education under their scientific and pedagogical supervision and motivates them to achieve ambitious educational goals that focus on developing an integrated personality for today’s students and tomorrow’s leaders. It is important to understand the impact of two proposed strategies based on active learning on the academic performance of first-class intermediate students in computer subjects and their social intelligence. The research sample was intentionally selected, consis

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Publication Date
Wed Dec 29 2021
Journal Name
Journal Of The College Of Education For Women
The Skills of Intended Meaning behind the Context when Reading Poetry among Fifth Grade Students- Literary Branch from Teachers’ Perspectives
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        The current research aims to investigate the skills of the intended meaning beyond the context when reading poetry among fifth literary students. To achieve the aim of the research, the researcher has followed the descriptive approach and used two tools: an open questionnaire that includes an inquiry about the skills of the intended meaning beyond the poetic context, and a closed questionnaire that were examined by the juries, and modified accordingly. Besides, its validity and stability were examined by applying the study on an exploratory sample of (15) teachers to reach its final version and determine the time required to answer it. Then, the researcher applied it on the research sample of (9

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Publication Date
Mon Jun 30 2008
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
The Relationships between the Physical and Chemical Properties of Narrow Fractions Distilled From Mixed Kirkuk and Sharki-Baghdad Crude Oils
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Mixed Kirkuk and Sharki-Baghdad crude oils were distilled into narrow fractions. The range of these narrow fractions were 10oC, starting from IBP to 350oC. The total distillates from mixed Kirkuk and Sharki-Baghdad crude oils were 58.25 vol % and 44.65 vol %, respectively.The hydrocarbons compositions (paraffin, naphthene, aromatic) in light fractions starting from IBP to 250oC were determined by using PONA analysis method. The results show that the paraffin content decreases with increasing mid percent boiling point of the fraction, while the naphthene, and aromatic increase with the increase of mid percent boiling point of mixed Kirkuk and Sharki-Baghdad crude oils. Three groups of empirical equations were developed for the prediction

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Publication Date
Sun Jan 04 2015
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Epidemiological Characteristics of Occupational Accidents Reported to the National Center for Occupational Safety and Health for the years 2011-2013
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Background: Understanding the risk factors associated with injuries at workplace is an essential element to design and implement preventive measures for such injuries which are a significant source of disability, death and socioeconomic losses worldwide.
Objectives: describe cases of occupational injuries with respect to person- place- time model.
Materials and methods: Cross-sectional study done from October 2013 to October 2014 carried on 467 records of occupational injuries kept in the National Center for Occupational Safety and Health for the years 2011-2013.
Results: Ahigher proportion of reported occupational accidents occurred in young male workers, during day time and among primary school graduat

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Publication Date
Sat Dec 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Causal relationship between sugar prices, imported sun flower oil, crude oil prices and the exchange rate of the Iraqi dinar
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Abstract

The increasing of some traded Agricultural crops prices coincide with the increasing of crude oil prices in global market since the beginning of 21st century which indicate the possibility of short run and long run causality relation between the imported economic variables. The study aims to analysis the causality effects between some of Agricultural crops prices imported by Iraq and the prices of crude oil and Iraq dinar exchange rate   in global markets for period (2004:1 -2016:4) theory for developing the adequate price and economic police for Iraqi economic sector. The results show the existence of short- run and long- run between the eco

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