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jih-447
Estimate AR(3) by Using Levinson-Durbin Recurrence & Weighted Least Squares Error Methods
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In this study, we investigate about the estimation improvement for Autoregressive model of the third order, by using Levinson-Durbin Recurrence (LDR) and Weighted Least Squares Error ( WLSE ).By generating time series from AR(3) model when the error term for AR(3) is normally and Non normally distributed and when the error term has ARCH(q) model with order q=1,2.We used different samples sizes and the results are obtained by using simulation. In general, we concluded that the estimation improvement for Autoregressive model for both estimation methods (LDR&WLSE), would be by increasing sample size, for all distributions which are considered for the error term , except the lognormal distribution. Also we see that the estimation improvement for WSLE method, depends on the value for the Forgetting Factor parameter (α),which haave value less than one(i.e. 1) ( α< ). The estimate is improved for large value for parameterα exactly at 0.99 α= .Finally, we used the estimation methods (LDR&WLSE) for real data.

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Publication Date
Sun Aug 01 2021
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Robust Tests for the Mean Difference in Paired Data by Using Bootstrap Resampling Technique
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The paired sample t-test for testing the difference between two means in paired data is not robust against the violation of the normality assumption. In this paper, some alternative robust tests have been suggested by using the bootstrap method in addition to combining the bootstrap method with the W.M test. Monte Carlo simulation experiments were employed to study the performance of the test statistics of each of these three tests depending on type one error rates and the power rates of the test statistics. The three tests have been applied on different sample sizes generated from three distributions represented by Bivariate normal distribution, Bivariate contaminated normal distribution, and the Bivariate Exponential distribution.

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Publication Date
Wed Aug 09 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Vaccination of chicken against Coccidiosis by using live Oocysts of different species of Eimeria
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The study was conducted to vaccinate chickens against coccidiosis  using alive vaccine contain seven species of chicken Eimeria,  E. tenella, E. brunetti, E. necatrix, E. maxima, E. mevati, E. acervulina  and E. praecox.    A total of 120 chicks were divided into two main groups: broiler group and egg laying group.  The birds of each group were allocated on to three pins, each contains 20 chicks.  The birds of the experiment were vaccinated at day nine of age, with a suspension of mixed Eimeria which contain 50 Oocysts of E. tenella with a different percent of other species, respectively.  The vaccine was given to chicks in the 1st pins of each group with drinking water,  the chicks in th

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Publication Date
Sun Jan 01 2023
Journal Name
Ssrn Electronic Journal
Design of Earthquake-Resistant Buildings by Using Reinforced Concrete or Steel Flexible Corner Joints
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This study focuses on studying the effect of reinforced steel in detail, and steel reinforcement (tensile ratio, compression ratio, size, and joint angle shape) on the strength of reinforced concrete (compressive strength) Fc' and searching for the most accurate details of concrete divisions, their behavior, and corner resistance of reinforced concrete joint. The comparison of this paper with previous studies, especially in the studied properties. The conclusions of the chapter are summarized that these effects had a clear effect and a specific effect on the behavior and resistance of the reinforced concrete corner joints under the negative moments and under their influence and the resulting stress conditions. The types of defects that can

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Publication Date
Fri Jun 01 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Detection of Increasing of Tropospheric NO2 over some Iraqi Cities by using Satellite Data
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This paper focus on study the variations of monthly tropospheric NO2 concentrations over three Iraqi cities Baghdad (33.3° N, 44.4° E), Basrah (30.56° N, 47.8° E) and Erbil (36.3° N, 44.06° E). Monthly NO2 retrievals from the Ozone Monitoring Instrument (OMI) onboard Aura satellite during the period from October 2004 to March 2013 have been used.  The results show a high monthly and annual NO2 concentrations at Baghdad than Basra and Erbil may be attribute to high densely populations and a high economic activity. During the whole period, Baghdad, Basrah and Erbil were exhibited an average of NO2 (8.1±2.5), (3.7±1.3) and (3.3±1.7) in unit 1015 molecules

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Publication Date
Tue Jun 30 2015
Journal Name
Al-kindy College Medical Journal
Compound fractures of the hand metacarpals and phalanges treated by using mini-external fixator
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Background: A review of articles of method in treating compound phalangeal fractures by using mini-external fixator, elaborating the anatomy, mechanics, modalities of treatment, and complications of these types of fractures. Also, it compares between different studies regarding the functional results and final outcome. External fixation of phalangeal fractures is a good method for osteo synthesis in certain situations. The simplicity of the surgical procedure and the minimal disruption of the normal bone architecture also make it appealing.Objectives: Evaluating the functional results of the use of mini-external fixator for the treatment of compound fractures of phalangeal bones of the hand.Method: Our study consists of 15 patients, 12 w

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Publication Date
Mon Dec 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Estimation Mean Wind Speed in Iraq By Using Parametric And Nonparametric Linear Mixed Models
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In this research, the one of the most important model and widely used in many and applications is linear mixed model, which widely used to analysis the longitudinal data that characterized by the repeated measures form .where estimating linear mixed model by using two methods (parametric and nonparametric) and used to estimate the conditional mean and marginal mean in linear mixed model ,A comparison between number of models is made to get the best model that will represent the mean wind speed in Iraq.The application is concerned with 8 meteorological stations in Iraq that we selected randomly and   then we take a monthly data about wind speed over ten years Then average it over each month in corresponding year, so we g

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Publication Date
Tue Jun 30 2015
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Improving Treatment Performance of Dissolved Air Flotation System by Using Ionic Liquids as Surfactants
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The effect of three ionic liquids viz., 1-hexyl-3-methylimidazolium tetrafluoroborate (ILE), 1-hexyl-3-metylimidazolium hexafluorophosphate (ILF) and 1-octyl-3-methylimidazolium tetrafluoroborate (ILG) when used as surfactants on the performance of dissolved air floatation (DAF) was investigated.

   Experiments were conducted at a temperature of 30-35 ºC, 10ppm ferric chloride as coagulant, 50% recycle ratio, pH 8, and 10 minutes treatment time  to find oil and grease (OG) and turbidity removal efficiencies at saturation pressure (2-6) bar.

ILs were used at concentration of 50 µl/liter of treated water in two positions in DAF system; the saturation vessel and the treatment tank. The performance using ILs

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Publication Date
Thu Dec 28 2023
Journal Name
Journal Of Physical Education
Proactive leadership and its relationship to managing the organizational error of the Iraqi Handball Federation from the point of view of the clubs participating in the Iraqi Elite League for the season 2023-2024
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This research seeks to study the role of proactive leadership as an essential element that helps all federations that lead the wheel of sports, including the Iraqi Handball Federation, so that it builds a correct environment that helps manage the organizational errors that the Handball Federation may fall into, and this in turn helps in early detection of errors and obstacles that may occur. It is likely that the Federation will fall into the process of managing and organizing the Iraqi Handball League, in addition to increasing the clubs’ ability to assist the Iraqi Handball Federation by being proactive so as not to make mistakes. The research community included the administrative bodies of the clubs participating in the Iraqi E

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Publication Date
Tue Dec 01 2015
Journal Name
Journal Of Al-nahrain University-science
Synthesis of Polyacrylamides from Derivatives 2-Aminobenzothiazole and also Preparation of Dibutylphthalate as a Plasticizer to Estimate Plasticization Behaviour for Prepared Polymers
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Publication Date
Wed Nov 01 2017
Journal Name
Journal Of Engineering
Stator Faults Diagnosis and Protection in 3-Phase Induction Motor Based on Wavelet Theory
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