Preferred Language
Articles
/
jeasiq-842
Estimation Mean Wind Speed in Iraq By Using Parametric And Nonparametric Linear Mixed Models
...Show More Authors

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 get different clusters ,each cluster contain 12 observation that represent a mean wind speed for each station  . The comparison among the best models are held by using statistical standard the mean square Error(MSE),our conclusion for the parametric model during the application the with additional  random effect(the second model) is better than the model without addithonal random effect(the first model)for all station in general,for nonparametric model we found the conditional local mixed model is better than marginal mixed model in estimation the conditional and marginal means for mixed model in general, for marginal mean , where found that the marginal local mixed model is better for all the stations that we were sampled except for the fifth station we found that the conditional local mixed model is better for the  marginal local mixed model in estimation of marginal mean mixed model .                                                                                                             

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Estimation the blast wave pressure effecters by apply Remote Sensing (RS) and Geographic Information System (GIS) techniques
...Show More Authors

After the year 2003 terrorist attacks knock Baghdad city capital of Iraq using bomb explosion various, shook the nation, and made public resident of Baghdad aware of the need for better ways to protect occupants, assets, and buildings cause the terrorist gangs adopt style burst of blast to injury vulnerability a wider range form, and many structures will suffer damage from air blast when the overpressure concomitant the blast wave, (i.e., the excess over the atmospheric pressure 14.7 pounds per square inch at standard sea level conditions are about one-half pound per square inch or more(
to attainment injury. Then, the distance to which this overpressure level will extend depends primarily on the energy yield (§1.20) of the burst of

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sun Jan 01 2023
Journal Name
نسق
التلكؤ االكاديمي لطلبة الاول متوسط (مدارس المتميزين )
...Show More Authors

الملخص: لتحقيق أهداف البحث قامت الباحثة اعداد مقياس التلكؤ الاكاديمي اعتمادا على نظرية (باندورا) وتكون المقياس بصورته النهائية من (21) فقرة ، وطبق المقياس على عينة البحث البالغة (100) طالب وطالبة تم اختيارهم بالطريقة العشوائية البسيطة من مجتمع البحث ،وبعد جمع البيانات تم معالجتها باستعمال الوسائل الإحصائية المناسبة، توصل البحث الى النتائج الأتية : الى ان الطلبة ليس لديهم تلكؤ اكاديمي و اعلى من المتوسط، لا توج

... Show More
Preview PDF
Publication Date
Mon Jun 01 2020
Journal Name
Journal Of Engineering
Pilot Based Channel Estimation and Synchronization in OFDM System
...Show More Authors

Channel estimation and synchronization are considered the most challenging issues in Orthogonal Frequency Division Multiplexing (OFDM) system. OFDM is highly affected by synchronization errors that cause reduction in subcarriers orthogonality, leading to significant performance degradation. The synchronization errors cause two issues: Symbol Time Offset (STO), which produces inter symbol interference (ISI) and Carrier Frequency Offset (CFO), which results in inter carrier interference (ICI). The aim of the research is to simulate Comb type pilot based channel estimation for OFDM system showing the effect of pilot numbers on the channel estimation performance and propose a modified estimation method for STO with less numb

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Tue Oct 29 2019
Journal Name
Journal Of Engineering
Demand Priority in a Power System With Wind Power Contribution Load Shedding Scheme Based
...Show More Authors

The load shedding  scheme has been extensively implemented as a fast solution for unbalance conditions. Therefore, it's crucial to investigate supply-demand balancing in order to protect the network from collapsing and to sustain stability as possible, however its implementation is mostly undesirable. One of the solutions to minimize the amount of load shedding is the integration renewable energy  resources, such as wind power, in the electric power generation could contribute significantly to minimizing power cuts as it is ability to positively improving the stability of the electric grid. In this paper propose a method for shedding the load base on the priority demands with incorporating the wind po

... Show More
View Publication Preview PDF
Crossref (9)
Crossref
Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Economics And Administrative Sciences
Fuzzy Bridge Regression Model Estimating via Simulation
...Show More Authors

      The main problem when dealing with fuzzy data variables is that it cannot be formed by a model that represents the data through the method of Fuzzy Least Squares Estimator (FLSE) which gives false estimates of the invalidity of the method in the case of the existence of the problem of multicollinearity. To overcome this problem, the Fuzzy Bridge Regression Estimator (FBRE) Method was relied upon to estimate a fuzzy linear regression model by triangular fuzzy numbers. Moreover, the detection of the problem of multicollinearity in the fuzzy data can be done by using Variance Inflation Factor when the inputs variable of the model crisp, output variable, and parameters are fuzzed. The results were compared usin

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Fri Jun 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
جدلية التنظرية في الذاكرة المنظمة بين متاهة النماذج الصناعية وواقعيةالنموذج الهجين
...Show More Authors

جدلية التنظرية في الذاكرة المنظمة بين متاهة النماذج الصناعية وواقعيةالنموذج الهجين

View Publication Preview PDF
Crossref
Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
A Comparative Study of Some Methods of Estimating Robust Variance Covariance Matrix of the Parameters Estimated by (OLS) in Cross-Sectional Data
...Show More Authors

 

Abstract

The Classical Normal Linear Regression Model Based on Several hypotheses, one of them is Heteroscedasticity as it is known that the wing of least squares method (OLS), under the existence of these two problems make the estimators, lose their desirable properties, in addition the statistical inference becomes unaccepted table. According that we put tow alternative,  the first one is  (Generalized Least Square) Which is denoted by (GLS), and the second alternative is to (Robust covariance matrix estimation) the estimated parameters method(OLS), and that the way (GLS) method neat and certified, if the capabilities (Efficient) and the statistical inference Thread on the basis of an acceptable

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Mar 30 2021
Journal Name
Baghdad Science Journal
Characterization of the Groundwater within Regional Aquifers and Suitability Assessment for Various Uses and Purposes-Western Iraq
...Show More Authors

Groundwater quality investigation has been carried out in the western part of Iraq (west longitude '40°40). The physicochemical analyses of 64 groundwater samples collected from seven aquifers were used in the determination of groundwater characterization and assessment. The concept of spatial hydrochemical bi-model was prepared for quantitative and qualitative interpretation. Hydrogeochemical data referred that the groundwater is of meteoric origin and has processes responsible for observed brackishness. The geochemical facies of the groundwater reveal that none of the anions and cations pairs exceed 50% and there are practically mixtures of multi-water types (such as Ca–Mg–Cl–HCO3 and Na+K–SO4–Cl water type) as do

... Show More
View Publication Preview PDF
Scopus (14)
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Wed Oct 17 2018
Journal Name
International Journal Of Civil Engineering And Technology (ijciet)
ESTIMATION OF MUNICIPAL SOLID WASTE GENERATION AND LANDFILL VOLUME GENERATION AND LANDFILL VOLUME USING ARTIFICIAL NEURAL NETWORKS
...Show More Authors

Publication Date
Sun Jun 20 2021
Journal Name
Baghdad Science Journal
Studying the Changes in Solar Radiation and Their Influence on Temperature Trend in Iraq for a Whole Century
...Show More Authors

Most studies indicated that the values ​​of atmospheric variables have changed from their general rates due to pollution or global warming etc. Hence, the research indicates the changes of direct solar radiation values ​​over a whole century i.e. from 1900 to 2000 depending on registered data for four cities, namely (Mosul - Baghdad - Rutba - Basra. Moreover, attemptsto correlate the direct solar radiation with the temperature values have been ​​recorded over that period. The results showed that there is a decreasing pattern of radiation quantities over time throughout the study period, where the value of direct radiation over the city of Baghdad 5550 w/m2 was recorded in the year 1900, but this ratio decreased cle

... Show More
View Publication Preview PDF
Scopus (8)
Crossref (1)
Scopus Clarivate Crossref