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Comparative Study of Performance and Emission Characteristics between Spark Ignition Engine and Homogeneous Charge Compression Ignition Engine (HCCI)
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Many researchers consider Homogeneous Charge Compression Ignition (HCCI) engine mode as a promising alternative to combustion in Spark Ignition and Compression Ignition Engines. The HCCI engine runs on lean mixtures of fuel and air, and the combustion is produced from the fuel autoignition instead of ignited by a spark. This combustion mode was investigated in this paper. A variable compression ratio, spark ignition engine type TD110 was used in the experiments. The tested fuel was Iraqi conventional gasoline (ON=82).

The results showed that HCCI engine can run in very lean equivalence ratios. The brake specific fuel consumption was reduced about 28% compared with a spark ignition engine. The experimental tests showed that the emissions concentrations were reduced by 91.27% for NOx, 85.99% for CO, 78.91% for CO2, and 83.56% for unburned hydrocarbons compared to the SI engine. HCCI engine produced little noise with about 26.68% less than SI engine.

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Publication Date
Sun Apr 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Designing and Application of Mathematical Model A Multi – Objectives for Assessment The Quality Of The Project : A Case Study at Saad Public Construction Company
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Abstract

This research aims to design a multi-objective mathematical model to assess the project quality based on three criteria: time, cost and performance. This model has been applied in one of the major projects formations of the Saad Public Company which enables to completion the project on time at an additional cost that would be within the estimated budget with a satisfactory level of the performance which match with consumer requirements. The problem of research is to ensure that the project is completed with the required quality Is subject to constraints, such as time, cost and performance, so this requires prioritizing multiple goals. The project

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Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of estimations methods of the entropy function to the random coefficients for two models: the general regression and swamy of the panel data
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In this study, we focused on the random coefficient estimation of the general regression and Swamy models of panel data. By using this type of data, the data give a better chance of obtaining a better method and better indicators. Entropy's methods have been used to estimate random coefficients for the general regression and Swamy of the panel data which were presented in two ways: the first represents the maximum dual Entropy and the second is general maximum Entropy in which a comparison between them have been done by using simulation to choose the optimal methods.

The results have been compared by using mean squares error and mean absolute percentage error to different cases in term of correlation valu

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Publication Date
Sun Apr 03 2016
Journal Name
Journal Of Educational And Psychological Researches
تقويم أداء طالبات الصف الأول المتوسط في مهارات القراءة الجهرية
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يرمي البحث الحالي الى تقويم أداء طالبات الصف الاول متوسط في مهارات القراءة الجهرية ، وذلك من خلال الاجابة عن هدفي البحث : 1- ما مستوى أداء طالبات الصف الأول المتوسط في كل مهارة من مهارات القراءة الجهرية ؟ 2- ما مستوى الأداء العام لطالبات الصف الأول المتوسط في القراءة الجهرية ؟ يقتصر البحث الحالي على: 1- مهارات القراءة الجهرية 2- عينة من مدارس البنات الن

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Publication Date
Fri Mar 02 2018
Journal Name
Alustath Journal For Human And Social Sciences
The Relationship Between Spatial Ability And The Physical Structure of concepts to The Students of The College of Education for Pure
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          The research aims to identify the relationship between spatial ability  and the physical structure of concepts to the students of the Faculty of Education for Pure Sciences / Ibn al-Haitham، research involved students from the third class / morning study for the year 2011/2012  totaling (98) male and female students ،distributed into three groups which were selected randomly . The number of students (26 males and females)  represented research sample after excluding repeaters and absentees، the research included two tests ; one test of spatial ability، which included (20) items and other test the physical structure of concepts، which included (12) items distributed into four domains ، the first (linking b

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Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
tourism planning and its impact in reducing the unemployment rate in Iraq for the period (1985 – 2015) An analytical study
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Abstract

     The problem of the study is the main question (Can tourism planning address the phenomenon of unemployment in Iraq ?) , And the importance of the study in the fact that the tourism sector can become an effective development alternative in many countries, especially Iraq, as tourism contributes to diversify sources of income and stimulate other economic sectors , We know how important Iraq's qualifications are in the field of tourism and what it can generate on the public treasury, To confirm the current study on the need to pay attention to tourism planning for its role in providing employment opportunities that reduce the unemployment rate in the future.

 &n

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Publication Date
Mon Jun 01 2015
Journal Name
Journal Of The College Of Languages (jcl)
ES’AT NAİB’İN “ZAMANIN ELİ” ADLI DİVANINDA İSİM ÇEKİM EKLERİ (Karşılaştırmalı İnceleme)
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Irak Türk ağızları Azeri Türkçesinin bir uzantısı olarak değerlendirilir.Kerkük Türkçesiyle yazılan edebi ürünler, Irak Türkçesinin tamamını ifade etmek üzere kullanılmaktadır. Zamanın Eli divanı Kerkük Türkçesile yazılan bir eserdir. Bu yüzden bu divanı seçtik ve Irak Türkmen Türkçesi , Osmanlı Türkçesi ve Türkiye Türkçesi dilleri arasında  karşılaştırmalı bir inceleme yaptık.

Bu araştırma, Irak Türkmen şairlerinden birisi  sayılan  Es’at Naib’in  şiirleri üzerinde uygulamalı bir çalışmadanoluşmaktadır. Bu çalışmada adı geçen şairin “Zamanın Eli” Divanından bazışiirlerini önce yeni Türkçeye çevirdik vedaha sonra isim ç

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Publication Date
Sun Dec 02 2012
Journal Name
Baghdad Science Journal
Study of Spectroscopy and Thermodynamic Properties for Phoshours dioxide PO2 Molecular and Influence Study of Bond ( P-O ) on Spectroscopy Properties
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In This research a Spectroscopic complement and Thermodynamic properties for molecule PO2 were studied . That included a calculation of potential energy . From the curve of total energy for molecule at equilibrium distance , for bond (P-O), the degenerated of bond energy was (4.332eV) instate of the vibration modes of ( PO2 ) molecule and frequency that was found active in IR spectra because variable inpolarization and dipole moment for molecule. Also we calculate some thermodynamic parameters of ( PO2 ) such as heat of formation , enthalpy , heat Of capacity , entropy and gibb's free energy Were ( -54.16 kcal/mol , 2366.45 kcal/mol , 10.06 kcal /k/mol , 59.52 k

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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Preparation Adhesive Material Reinforced of Graphite Particles and Study Electrical and Mechanical and Thermal Properties
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The physical, mechanical, electrical and thermal properties containing (Viscosity, curing, adhesion force, Tensile strength, Lap shear strength, Resistively, Electrical conductivity and flammability) of adhesive material that prepared from Nitrocellulose reinforced with graphite particles and aluminum streat. A comparison is made between the properties of adhesive material with varying percentage of graphite powder (0%, 25%, 30%, 35%, 40%) to find out the effect of reinforcement on the adhesive material. The ability of property an electrical was studied through the measurement of conductivity a function of temperature varying. The results of comparison have clearly shown that the increasing of conten

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Publication Date
Sat Jan 01 2011
Journal Name
Al-mustansiriyah Journal Of Science
TMA and DSC study of molded and annealed polyester: a thermal expansion and crystallization evaluation
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Thermomechanical analysis (TMA) and differential scanning calorimetry (DSC) are used to investigate the effect of molding and annealing of polyester on the behavior of thermal expansion and crystallization since these factors play role in the reprocessing or recycling of the polymer. The dynamic mode of the TMA provides enhanced characterization information about the polyester since it separates the transitions into reversible and irreversible signals, and also reveals the progress of the amorphous regions as the polyester loses strength with the increasing temperature approaching melting. Slow cooling after annealing brings crystallization that may be attributed to molecular chain straightening due to orientation.

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Publication Date
Fri Oct 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Accounting measurement of intangible assets (websites) within the framework of international financial reporting standards An applied study between a sample of Iraqi commercial banks)
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The websites over time have become one of the important tools for communication between individuals among themselves and between individuals and economic units, and they have emerged as one of the important intangible assets to achieve income, as they have become a competitive tool and a marketing outlet for these units and a main means of communication that it uses to exercise its various major activities and achieve potential economic benefits. Therefore, there was a need to measure and display the value of these sites in the financial statements as intangible assets.  Accordingly, the purpose of the research was to determine the costs of the websites owned by the economic unit by way purchase and sites that were created i

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