Preferred Language
Articles
/
alkej-199
A new Cumulative Damage Model for Fatigue Life Prediction under Shot Peening Treatment
...Show More Authors

 Abstract

In this paper, fatigue damage accumulation were studied using many methods i.e.Corton-Dalon (CD),Corton-Dalon-Marsh(CDM), new non-linear model and experimental method. The prediction of fatigue lifetimes based on the two classical methods, Corton-Dalon (CD)andCorton-Dalon-Marsh (CDM), are uneconomic and non-conservative respectively. However satisfactory predictions were obtained by applying the proposed non-linear model (present model) for medium carbon steel compared with experimental work. Many shortcomings of the two classical methods are related to their inability to take into account the surface treatment effect as shot peening. It is clear that the new model shows that a much better and conservative prediction of fatigue life in comparison with CD and CDM methods. The prediction of the present model gave slightly below the experimental data while the CDM gave overestimate prediction and CD showed strongly underestimates the life of specimens.

 

Keywords: Cumulative fatigue damage, Shot peening, Non-linear model.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Dec 29 2017
Journal Name
Al-khwarizmi Engineering Journal
Microcontroller – Based Spectrum Analyzer
...Show More Authors

This work includes design, implementation and testing of a microcontroller – based spectrum analyzer system. Both hardware and software structures are built to verify the main functions that are required by such system. Their design utilizes the permissible and available tools to achieve the main functions of the system in such a way to be modularly permitting any adaptation for a specific changing in the application environment. The analysis technique, mainly, depends on the Fourier analysis based methods of spectral analysis with the necessary required preconditioning processes. The software required for waveform analysis has been prepared. The spectrum of the waveform has been displayed, and the instrument accuracy has been checked.

... Show More
View Publication
Publication Date
Tue Aug 20 2019
Journal Name
Political Sciences Journal
Moved movement the dynamics of conflict and the restructuring of balance maps in Syria
...Show More Authors

This study deals with the absence of state control over the whole of the Syrian geography in creating an environment conducive to the emergence of a new force represented by armed groups and organizations that point to fundamental changes in the conflict and to transform competition for control over the land into a struggle for influence. Which in itself represents the prospects of change in the Syrian scene, and that understanding their interests requires shedding light on the extent of the continuation of this competition and the conflict on land and expansion at the expense of the other, and thus contribute to complicate the Syrian scene, especially after attempts to bite Of land and annexation to each party's areas of influence, espe

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Jan 17 2025
Journal Name
Journal Of Al-qadisiyah For Computer Science And Mathematics
Modified LASS Method Suggestion as an additional Penalty on Principal Components Estimation – with Application-
...Show More Authors

This research deals with a shrinking method concernes with the principal components similar to that one which used in the multiple regression “Least Absolute Shrinkage and Selection: LASS”. The goal here is to make an uncorrelated linear combinations from only a subset of explanatory variables that may have a multicollinearity problem instead taking the whole number say, (K) of them. This shrinkage will force some coefficients to equal zero, after making some restriction on them by some "tuning parameter" say, (t) which balances the bias and variance amount from side, and doesn't exceed the acceptable percent explained variance of these components. This had been shown by MSE criterion in the regression case and the percent explained v

... Show More
View Publication Preview PDF
Publication Date
Fri Jan 17 2025
Journal Name
Iraqi Journal Of Science
Specification of Actual Evapotranspiration in Iraq by GIS
...Show More Authors

     Evapotranspiration (ET) is produced from vegetation transpiration and soil evaporation. The ET measurements must be considered to study water management systems and irrigation (planning, designing and operating). This study is based on USGS (United States Geological Survey) data by the SSEBop (Simplified Surface Energy Balance) model to estimate the total annual amount of ET using ArcGIS software. The ET values were determined for seventeen years from 2003 to 2019. Also, these values for year 2020 were estimated based on the value of the monthly ET for seven months, i.e. until August by summation. The field data of gauge stations spread throughout Iraq for the year 2012 were used to verify the ET values for the s

... Show More
View Publication Preview PDF
Scopus (2)
Scopus
Publication Date
Sat Dec 30 2023
Journal Name
Modern Sport
تأثير منهج تعليمي وفق أنموذج بايبي على تعلم بعض مهارات الكرة الطائرة للطالبات بكلية التربية البدنية وعلوم الرياضة
...Show More Authors

أن أهمية البحث تكمن في أعداد منهج تعليمي مقترح وفق أنموذج بايبي وتعلم مهارتي الاعداد وأستقبال الارسال بالكرة الطائرة للطالبات وتكمن أهمية أنموذج بايبي بالمساعدة على توظيف المعلومات في المواقف المختلفة،وان مشكلة البحث جاءت بعد أطلاع الباحثات على الدراسات والمصادر السابقة لاحظت بأن هناك ضعف في الاداء المهاري في مهارتي الاعداد وأستقبال الارسال بالكرة الطائرة من قبل الطالبات لذلك أرتأت الباحثات الى التع

... Show More
Crossref
Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Statistical testing mediation in structural equations models variables with practical application
...Show More Authors

In this research was the study of a single method of estimation and testing parameters mediating variables (Mediation) in a specimen structural equations SEM a bootstrap method, for the purpose of application of the integrated survey of the situation Marital data and health mirror Iraqi (I-WISH) for the year 2011 from the Ministry of Planning - device Central Bureau of Statistics, and applied to the appropriate data from the terms of the data to a form of structural equation SEM using factor analysis affirmative (Confirmatory Factor analysis) CFA As a way to see the match variables that make up the model, and after confirming the model matching or suitability are having the effect of variables mediation in the model tested by the

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Apr 04 2010
Journal Name
Journal Of Educational And Psychological Researches
بناء مقياس معنى الحياة كما تدركه طالبة الجامعة على وفق Multidimensional Item Response Model
...Show More Authors

The undimensionality hypothesis which is item response theory depend it is unable in some of measurement situations because there are many dimensions which are affect of the response, so as the researches reached to expand this hypothesis to construct a new one which is multidimensional, and many of theories are pointed to the concept of meaning of life is multidimensionality, so this research aimed to construct the scale of meaning of life as the student's perception according with Multidimensional Item Response Model and this research adopt Wong's theory 1998 which point to the meaning of life consist of (7) dimensions. The research tool contains (49) items distributed at dimensions of meaning of life. Sample of statistical ana

... Show More
View Publication Preview PDF
Publication Date
Wed Dec 18 2019
Journal Name
Baghdad Science Journal
The Calculation and Analysis of the Total Electron Content Over Different Latitudes and Seasons Using the Numerical Trapezoidal and Simpson Methods
...Show More Authors

It has been shown in ionospheric research that calculation of the total electron content (TEC) is an important factor in global navigation system. In this study, TEC calculation was performed over Baghdad city, Iraq, using a combination of two numerical methods called composite Simpson and composite Trapezoidal methods. TEC was calculated using the line integral of the electron density derived from the International reference ionosphere IRI2012 and NeQuick2 models from 70 to 2000 km above the earth surface. The hour of the day and the day number of the year, R12, were chosen as inputs for the calculation techniques to take into account latitudinal, diurnal and seasonal variation of TEC. The results of latitudinal variation of TE

... Show More
View Publication Preview PDF
Scopus Clarivate Crossref
Publication Date
Fri Nov 24 2023
Journal Name
Iraqi Journal Of Science
Modeling and Stability of Lotka-Volterra Prey-Predator System Involving Infectious Disease in Each Population
...Show More Authors

In this paper, a mathematical model consisting of the prey- predator model with disease in both the population is proposed and analyzed. The existence, uniqueness and boundedness of the solution are discussed. The existences and the stability analysis of all possible equilibrium points are studied. Numerical simulation is carried out to investigate the global dynamical behavior of the system.

View Publication Preview PDF
Publication Date
Sun Aug 30 2020
Journal Name
Periodicals Of Engineering And Natural Sciences (pen)
Kernel estimation of returns of retirement funds of employers based on monetary earnings (subscriptions and compensation) via regression discontinuity in Iraq
...Show More Authors

Regression Discontinuity (RD) means a study that exposes a definite group to the effect of a treatment. The uniqueness of this design lies in classifying the study population into two groups based on a specific threshold limit or regression point, and this point is determined in advance according to the terms of the study and its requirements. Thus , thinking was focused on finding a solution to the issue of workers retirement and trying to propose a scenario to attract the idea of granting an end-of-service reward to fill the gap ( discontinuity point) if it had not been granted. The regression discontinuity method has been used to study and to estimate the effect of the end -service reward on the cutoff of insured workers as well as t

... Show More
View Publication Preview PDF