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bsj-8819
Processing of Polymers Stress Relaxation Curves Using Machine Learning Methods
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Currently, one of the topical areas of application of machine learning methods is the prediction of material characteristics. The aim of this work is to develop machine learning models for determining the rheological properties of polymers from experimental stress relaxation curves. The paper presents an overview of the main directions of metaheuristic approaches (local search, evolutionary algorithms) to solving combinatorial optimization problems. Metaheuristic algorithms for solving some important combinatorial optimization problems are described, with special emphasis on the construction of decision trees. A comparative analysis of algorithms for solving the regression problem in CatBoost Regressor has been carried out. The object of the study is the generated data sets obtained on the basis of theoretical stress relaxation curves. Tables of initial data for training models for all samples are presented, a statistical analysis of the characteristics of the initial data sets is carried out. The total number of numerical experiments for all samples was 346020 variations. When developing the models, CatBoost artificial intelligence methods were used, regularization methods (Weight Decay, Decoupled Weight Decay Regularization, Augmentation) were used to improve the accuracy of the model, and the Z-Score method was used to normalize the data. As a result of the study, intelligent models were developed to determine the rheological parameters of polymers included in the generalized non-linear Maxwell-Gurevich equation (initial relaxation viscosity, velocity modulus) using generated data sets for the EDT-10 epoxy binder as an example. Based on the results of testing the models, the quality of the models was assessed, graphs of forecasts for trainees and test samples, graphs of forecast errors were plotted. Intelligent models are based on the CatBoost algorithm and implemented in the Jupyter Notebook environment in Python. The constructed models have passed the quality assessment according to the following metrics: MAE, MSE, RMSE, MAPE. The maximum value of model error predictions was 0.86 for the MAPE metric, and the minimum value of model error predictions was 0.001 for the MSE metric. Model performance estimates obtained during testing are valid.

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Publication Date
Mon Aug 22 2022
Journal Name
Biochemical And Cellular Archives
Measurement of inflammation and oxidative stress biomarkers induced by cigarette smoke among Iraqi smokers.
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To determine the association between cigarette smoking and oxidative stress, a study was conducted in the period from January 2020 to April 2021, at College of Medicine, Al-Nahrain University, Baghdad, Iraq. The Enzyme-linked immunosorbent assay (ELISA) technique was utilized for measurement the antioxidant enzymes including: Glutathione superoxide (GPX) and catalase (CAT) and the biomarker of lipid peroxidation Malondialdehyde (MDA). Also, the gene expression of Nrf2 and HO-1were determined by using RT-PCR technique. The results indicate lower level of both GPX and CAT (p ≤ 0.001) in smokers compared with non-smokers. While the result of MDA indicate higher level in smokers (p≤0.001) compared with nonsmokers. The Nrf2 and HO-1 gene exp

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Publication Date
Sun Jul 06 2014
Journal Name
Journal Of Educational And Psychological Researches
The Intellectual Stress and Its Relationship with Personality' s Five Major Factors of Counselors
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The current study aims at identifying:

1-The intellectual stress of counselors according to gender variable (male, female ).

2-The five major  factors of the  Counselor's  Personality.

3-  The relationship between intellectual stress and the five major factors of the councilors' personality and according to gender variable (male, female ).

4-The significant differences in the relationship between intellectual stress and the five major factors of the councilors' personality and according to gender variable  (male, female ).

The sample of the study includes (260) counselors (130 male

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Publication Date
Tue Nov 11 2014
Journal Name
Pakistan Journal Of Biological Sciences
Effects of Local Curcumin on Oxidative Stress and Total Antioxidant Capacity in vivo Study
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Publication Date
Mon Jun 19 2023
Journal Name
Journal Of Engineering
An Analysis of Stress Distribution in a Spline Shaft Subjected to Cycilc Impulsive Load
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In this paper the effect of engagement length, number of teeth, amount of applied load, wave propagation time, number of cycles, and initial crack length on the principal stress distribution, velocity of crack propagation, and cyclic crack growth rate in a spline coupling subjected to cyclic torsional impact have been investigated analytically and experimentally. It was found that the stresses induced due to cyclic impact loading are higher than the stresses induced due to impact loading with high percentage depends on the number of cycles and total loading time. Also increasing the engagement length and the number of teeth reduces the principal stresses (40%) and
(25%) respectively for increasing the engagement length from (0.15 to 0

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Publication Date
Wed Nov 07 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
The Effect of Different Types of Separating Medium On Some Physical Properties of Processing Acrylic Denture-base with Two Investment Materials: A comparative Study
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Objective(s): In the present study, glycerin is used as a substitute for tin-foil and cold mold seal (Alginate mould seal)
in the process of curing heat and cold-cure acrylic resin denture base against stone and plaster.
Methodology: 60 specimens were prepared from heat-cure acrylic resin and cold-cure acrylic resin denture base. The
study includes 12 groups of specimens depending on the type of processing, investment material and type of
separating medium that are used in curing process. Each group of them contains 5 specimens for each test.
Some of physical properties of the processed acrylic denture base that (water sorption and solubility) have been
compared with those processed using tin-foil and tin-foil substitut

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Publication Date
Fri Sep 01 2006
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
العلاقة بين تدعيم نظم الرقابة المالية و معالجة نواحي الفساد الإداري والمالي
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إن الاستخدام الفعال للأموال العامة يشكل احد الدعامات الأساسية من اجل حسن إدارة تلك الأموال و فعالية القرارات الصادرة عن السلطات المختصة ، و أن هذا الهدف لا يتحقق ما لم تكون الرقابة المالية ذات فعالية لكبح جماح حالات الفساد الإداري النظمي و تفشي ذلك في جهاز الدولة الإداري. لان ظاهرة الفساد الإداري تؤدي بجهاز الدولة الإداري إلى فقدان كيانه الموحد لصالح المنظومات الفاسدة رغم احتفاظه بكيانه الموحد شكليا، كما ت

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
دور حوكمة الشركات في معالجة الاختلالات الهيكلية في سوق العراق للاوراق المالية
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تعد حوكمة الشركات Governance  من المواضيع التي تهم العديد من الباحثين والمنظمات المهنية والدولية في فروع عديدة من المعرفة ، حيث يتضمن مفهوم حوكمة الشركات الاطار الذي يتم من خلاله وضع أهداف الشركات والمتمثله في حماية مصالح حملة الاسهم والاخرين من أصحاب المصلحه ، وتعظيم أداء الشركات وتقليل المخاطر وتحسين فرص الوصول الى أسواق رأس المال.  وان احد اسباب ظهور حوكمة الشركات هو وجود عدد من الاختلالات الهيكلية في ا

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Publication Date
Wed Dec 31 2025
Journal Name
Al-qadisiya Journal
معالجة النقص التشريعي بالاجتهاد القضائي المسؤولية التقصيرية الناشئة عن الذكاء الاصطناعي انموذجًا
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Publication Date
Fri Dec 02 2022
Journal Name
Journal Of Physical Education
The Effect of Jigsaw Strategy on Learning Spiking in Volleyball for Sophomore Students
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The research aimed at designing teaching program using jigsaw in learning spiking in volleyball as well as identifying the effect of these exercises on learning spring in volleyball. The researchers used the experimental method on (25) students as experimental group and (27) students as controlling group and (15) students as pilot study group. The researchers conducted spiking tests then the data was collected and treated using proper statistical operations to conclude that the strategy have a positive effect in experimental group. Finally, the researchers recommended using the strategy in making similar studies on other subjects and skills.

Publication Date
Sun Sep 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Compared Methods of Generating Both Gamma Distribution and Beta Distribution
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Beta Distribution

Abstract

             Gamma and Beta Distributions has very important in practice in various areas of statistical and applications reliability and quality control of production. and There are a number of methods to generate data behave on according to these distribution. and These methods bassic primarily on the shape parameters of each distribution and the relationship between these distributions and their relationship with some other probability distributions.    &nb

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