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مقارنة الانحدار الشرائحي المعكوس مع المركبات الرئيسة في اختزال البيانات ذات الابعاد العالية بأستعمال المحاكاة
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 يدرس هذا البحث طرائق اختزال الابعاد التي تعمل على تجاوز مشكلة البعدية عندما تفشل الطرائق التقليدية في ايجاد تقدير جيد للمعلمات، لذلك يتوجب التعامل مع هذه المشكلة بشكل مباشر. ومن اجل ذلك، يجب التخلص من هذه المشكلة لذا تم استعمال اسلوبين لحل مشكلة البيانات ذات الابعاد العالية الاسلوب الاول طريقة الانحدار الشرائحي المعكوس SIR ) ) والتي تعتبر طريقة غير كلاسيكية  وكذلك طريقة ( WSIR ) المقترحة والاسلوب الثاني طريقة المركبات الرئيسة ( PCA ) وهي الطريقة العامة المستخدمة في اختزال الابعاد ,  ان عمل طريقة انحدار الشرائحي المعكوس SIR ) ) و طريقة المركبات الرئيسة (PCA) يقوم على عمل توليفات خطية مختزلة من مجموعة جزئية من المتغيرات التوضيحية الأصلية والتي قد تعاني من مشكلة عدم التجانس ومن مشكلة التعدد الخطي بين معظم المتغيرات التوضيحية , وستقوم هذه التوليفات الجديدة المتمثلة بالمركبات الخطية الناتجة من الطريقتين بإختزال أكثر عدد من المتغيرات التوضيحية للوصول الى بُعد جديد واحد او اكثر  يسمى بالبعد الفعّال . وسيتم استعمال معيار جذر متوسط مربعات الخطأ للمقارنة بين الاسلوبين لبيان  افضلية الطرائق , وقد تم اجراء دراسة محاكاة للمقارنة بين الطرائق المستعملة  وقد بينت نتائج المحاكاة ان طريقة weight standard Sir  المقترحة هي الافضل .

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Publication Date
Sat Oct 01 2011
Journal Name
Journal Of Engineering
MECHANICAL DEGRADATION OF HIGH MOLECULAR WEIGHT POLYMER WITH SURFACTANT ADDITION IN A ROTATING DISK APPARATUS
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Mechanical degradation hampers the practical usage of polymers for turbulent drag reduction
application. Mechanical degradation refers to the chemical process in which the activation energy of
polymer chain scission is exceeded by mechanical action on the polymer chain, and bond rupture
occurs. When a water-soluble polymer and surfactant are mixed in water solution, the specific structures
(aggregates) are formed, in which polymer film is formed around micelle. In this work, Xanthan gum (XG) –
Sodium lauryl ether sulfate (SELS) complex formation and its effect on percentage viscosity reduction
(%VR) was studied. It was found that SELS surfactant reduced the mechanical degradation of XG much
more efficiently than th

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Publication Date
Tue Jun 01 2021
Journal Name
Journal Of Engineering Science And Technology
Membrane Fouling Reduction for Reverse Osmosis System Using Zeta Rod
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Reverse osmosis membrane desalination is one of the most significant water treatments that is used to offer freshwater. The aim of this research is to study the effect of controlling the value of the zeta potential on the suspended particles in the water and the proximity of the membrane surfaces in the colloidal solution, to keep the water stable electrically and disperse the colloidal particles. To achieve this aim, the experimental study was conducted in the Sanitary Engineering Laboratory, in the engineering college - University of Baghdad. Two systems were set up, one worked normally and the other worked by using the zeta rod placed before the reverse osmosis membrane. The results showed that the effect of the zeta rod increas

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Publication Date
Mon Jun 01 2020
Journal Name
Journal Of Engineering
Artificial Neural Network (ANN) for Prediction of Viscosity Reduction of Heavy Crude Oil using Different Organic Solvents
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The increase globally fossil fuel consumption as it represents the main source of energy around the world, and the sources of heavy oil more than light, different techniques were used to reduce the viscosity and increase mobility of heavy crude oil. this study focusing on the experimental tests  and modeling with Back Feed Forward Artificial Neural Network (BFF-ANN) of the dilution technique to reduce a  heavy oil viscosity that was collected from the south- Iraq oil fields using organic solvents, organic diluents with different weight percentage  (5, 10 and  20 wt.% )  of  (n-heptane, toluene, and a mixture of  different ratio

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Publication Date
Sun Mar 17 2019
Journal Name
Baghdad Science Journal
A Study on the Accuracy of Prediction in Recommendation System Based on Similarity Measures
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Recommender Systems are tools to understand the huge amount of data available in the internet world. Collaborative filtering (CF) is one of the most knowledge discovery methods used positively in recommendation system. Memory collaborative filtering emphasizes on using facts about present users to predict new things for the target user. Similarity measures are the core operations in collaborative filtering and the prediction accuracy is mostly dependent on similarity calculations. In this study, a combination of weighted parameters and traditional similarity measures are conducted to calculate relationship among users over Movie Lens data set rating matrix. The advantages and disadvantages of each measure are spotted. From the study, a n

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Publication Date
Sun Dec 09 2018
Journal Name
Baghdad Science Journal
Some Results on the Average Inverse Shadowing Property and Strong Ergodicity
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Publication Date
Mon Jun 30 2014
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Study the Performance of Low Cost Material (Peanut Hulls) for Dye Adsorption Using Inverse Fluidized Bed
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The present study dealt with the removal of methylene blue from wastewater by using peanut hulls (PNH) as adsorbent. Two modes of operation were used in the present work, batch mode and inverse fluidized bed mode. In batch experiment, the effect of peanut hulls doses 2, 4, 8, 12 and 16 g, with constant initial pH =5.6, concentration 20 mg/L and particle size 2-3.35 mm were studied. The results showed that the percent removal of methylene blue increased with the increase of peanut hulls dose. Batch kinetics experiments showed that equilibrium time was about 3 hours, isotherm models (Langmuir and Freundlich) were used to correlate these results. The results showed that the (Freundlich) model gave the best fitting for adsorption capacity. D

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Publication Date
Mon Mar 03 2025
Journal Name
Internationaljournalof Economicsandfinancestudies
CROSS-SECTIONAL REGRESSION WITH PROXIES: A SEMI-PARAMETRIC METHOD
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This study investigates asset returns within the Iraq Stock Exchange by employing both the Fama-MacBeth regression model and the Fama-French three-factor model. The research involves the estimation of cross-sectional regressions wherein model parameters are subject to temporal variation, and the independent variables function as proxies. The dataset comprises information from the first quarter of 2010 to the first quarter of 2024, encompassing 22 publicly listed companies across six industrial sectors. The study explores methodological advancements through the application of the Single Index Model (SIM) and Kernel Weighted Regression (KWR) in both time series and cross-sectional analyses. The SIM outperformed the K

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Scopus
Publication Date
Sat Sep 30 2023
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
A model of a proposed audit program to audit the strategies of municipal institutions and its impact on achieving sustainable development: An applied research in the municipal institutions of Karbala Governorate
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Abstract

                  The study aimed to prepare a practical guide for procedures for auditing the strategies of municipal institutions in achieving sustainable development by adopting the idea of ​​the audit matrix through which a classified report is prepared according to the dimensions of sustainable development, by preparing a specialized audit program for the purpose of auditing strategies for achieving sustainable development and emptying the results of the application of each of the paragraphs The program in the audit matrix that was prepared for the purpose of determining the impact of each observation and linkin

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Publication Date
Thu Oct 01 2015
Journal Name
Journal Of Engineering
Modeling and Optimization the Influence of CO2-MAG Welding Parameters on the Weld Joint Shape Factors
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This paper represents an experimentalattempt to predict the influence of CO2-MAG welding variables on the shape factors of the weld joint geometry. Theinput variables were welding arc voltage, wire feeding speed and gas flow rate to investigate their effects on the shape factorsof the weld joint geometry in terms of weld joint dimensions (bead width, reinforcement height, and penetration). Design of experiment with response surface methodology technique was employed to buildmathematical models for shape factors in terms of the input welding variables. Thepredicted models were found quadratic type and statistically checked by ANOVA analysis for adequacy purpose. Also, numerical and graphical optimizations were carried out

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Publication Date
Wed Jun 01 2016
Journal Name
Journal Of Engineering
A Novel Analytical Model to Design Piezoelectric Patches Used to Repair Cracked Beams
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In this paper, an analytical solution describing the deflection of a cracked beam repaired with piezoelectric patch is introduced. The solution is derived using perturbation method. A novel analytical model to calculate the proper dimensions of piezoelectric patches used to repair cracked beams is also introduced. This model shows that the thickness of the piezoelectric patch depends mainly on the thickness of the cracked beam, the electro-mechanical properties of the patch material, the applied load and the crack location. Furthermore, the model shows that the length of the piezoelectric patches depends on the thickness of the patch as well as it depends on the length of the cracked beam and the crack depth. The additio

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