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Estimation of Copula Density Using the Wavelet Transform
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يقترح هذا البحث طريقة جديدة لتقدير دالة كثافة الرابطة باستخدام تحليل المويجات كطريقة لامعلمية، من أجل الحصول على نتائج أكثر دقة وخالية من مشكلة تاثيرات الحدود التي تعاني منها طرائق التقدير اللامعلمية. اذ تعد طريقة المويجات طريقة اوتماتيكية للتعامل مع تاثيرات الحدود وذلك لانها لا تأخذ بنظر الاعتبار إذا كانت السلسلة الزمنية مستقرة او غير مستقرة. ولتقدير دالة كثافة الرابطة تم استعمال المحاكاة لتوليد البيانات وباستعمال خمسة دوال رابطة مختلفة مثل Gaussian وFrank وTawn وRotation Tawn وJoe وبخمسة أحجام مختلفة للعينات عند ثلاثة مستويات ارتباط موجبة، واعتمادًا على الحلول المتعددة، أظهرت النتائج أن تقدير دالة الكثافة الرابطة بطريقة المويجات عندما يكون مستوى الارتباط  كانت الرابطة Gaussian في المرتبة الأولى تليها الرابطةFrank واحتلت الرابطة Joe   المرتبة الأخيرة. اما في حالة الارتباطات المتوسطة والضعيفة   كانت الرابطة Tawn في المرتبة الأولى تليها الرابطة Rotation Tawn في حين جاءت Gaussian بالمرتبة الأخيرة. بالاعتماد على المعايير (Root Mean Square Error, Akiake Information Criteria, and Logarithm likelihood criteria) ، وتبين من خلال الرسم (Contour plot)  والشكل ثلاثي الابعاد (3D plot) لدوال الرابطة الحقيقية. فضلا عن اشكال التمهيد لكل منها باستخدام طريقة (ECDWT)، ويتضح من خلال الاشكال الدائرية ان توزيع مشاهدات الدالة الرابطة المقدرة بطريقة (ECDWT) كان دقيقا عند الاطراف بينما كان اقل دقة عند المركز لكل من الدوال Gaussian   وTawn.

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Publication Date
Sat Apr 01 2023
Journal Name
Iraqi Journal Of Applied Physics
Calculations of Nuclear Two-Component State Density in Non-Equidistant Spacing Model with Modified Williams
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Publication Date
Thu Sep 13 2012
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Density and Viscosity of Amino Acid Serine in aqueous dimethyl sulfoxide solution at deferent temperatures
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Publication Date
Fri Feb 03 2012
Journal Name
Ibn Al-haitham Journal For Pure And Applied Science
Viscosity and Density of Chrom Alum in Aqueous Poly (Ethylene Glycol) Solution at Different Temperature
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Density data of alum chrom in water and in aqueous solution of poly (ethylene glycol) (1500) at different temperatures (288.15, 293.15, 298.15) k have been used to estimate the apparent molar volume (Vθ), limiting apparent molar volume (Vθ˚) experimental slope (Sv) and the second derivative of limiting partial molar volume [δ2 θ v° /δ T2] p .The viscosity data have been analyzed by means of Jones –Dole equation to obtain coefficient A, and Jones –Dole coefficient B, Free activation energy of activation per mole of solvent, Δμ10* solute, Δμ20* the activation enthalpy ΔH*,and entropy, ΔS*of activation of viscous flow. These results have been discussed in terms of solute –solvent interaction and making/breaking ability of so

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Publication Date
Fri Jan 30 2015
Journal Name
Journal Of Madenat Alelem College
Estimation of Liver Enzymes and Total Bilirubin Level in the sera of patients infected with liver hydatid cysts
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This study included 46 patients with liver hydatid cyst diagnosed clinically and surgically. Control group consist of 22 healthy volunteers. The patients were divided according to the size of the cysts into more and less than 5 cm diameter size, 33 and 13, respectively. Also they were divided into primary and secondary hydatid cyst infection, 30 and 16, respectively. Significant increase of GOT, GPT and ALP levels were recorded due to hydatid cyst infection and had direct effect on the liver function, beside an increase in total bilirubin in patients serum compared with the control, also the same occurred in the secondary infection compared with primary infection, patients with> 5 cm showed significant increase in the above levels compared

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Publication Date
Fri Nov 07 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Estimation of the linear dimensional changes of autoclave cured acrylic resin with multiple palatal depths and investment materials
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Background: Dimensional changes of acrylic denture bases after polymerization results in need for further adjustments or even ends with technical failure of the finished dentures. The purpose of this study was to estimate the linear dimensional changes for different palatal depths when using multiple investment materials and polymerization techniques. Materials and methods: Ninety upper complete denture bases were constructed for this study. They were divided into two main groups according to the polymerization methods: conventional water bath and experimental autoclave (short and long cycles). Each main group was further subdivided into three subgroups according to the palatal depth (shallow, medium and deep). Furthermore, for each palatal

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Publication Date
Fri Apr 12 2019
Journal Name
Journal Of Economics And Administrative Sciences
Compare between simex and Quassi-likelihood methods in estimation of regression function in the presence of measurement error
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       In recent years, the attention of researchers has increased of semi-parametric regression models, because it is possible to integrate the parametric and non-parametric regression models in one and then form a regression model has the potential to deal with the cruse of dimensionality in non-parametric models that occurs through the increasing of explanatory variables. Involved in the analysis and then decreasing the accuracy of the estimation. As well as the privilege of this type of model with flexibility in the application field compared to the parametric models which comply with certain conditions such as knowledge of the distribution of errors or the parametric models may

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Engineering
ESTIMATION THE 7 AND 28- DAY NORMAL COMPRESSIVE STRENGTH BY ACCELERATED TEST METHODS IN CONCRETE
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Curing of concrete is the maintenance of a satisfactory moisture content and temperature for a
period of time immediately following placing so the desired properties are developed. Accelerated
curing is advantages where early strength gain in concrete is important. The expose of concrete
specimens to the accelerated curing conditions which permit the specimens to develop a significant
portion of their ultimate strength within a period of time (1-2 days), depends on the method of the
curing cycle.Three accelerated curing test methods are adopted in this study. These are warm water,
autogenous and proposed test methods. The results of this study has shown good correlation
between the accelerated strength especially for

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Publication Date
Thu May 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Channel Estimation and Prediction Based Adaptive Wireless Communication Systems
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Wireless channels are typically much more noisy than wired links and subjected to fading due to multipath  propagation which result in ISI and hence high error rate. Adaptive modulation is a powerful technique to improve the tradeoff between spectral efficiency and Bit Error Rate (BER). In order to adjust the transmission rate, channel state information (CSI) is required at the transmitter side.

In this paper the performance enhancement of using linear prediction along with channel estimation to track the channel variations and adaptive modulation were examined. The simulation results shows that the channel estimation is sufficient for low Doppler frequency shifts (<30 Hz), while channel prediction is much more suited at

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Publication Date
Thu Feb 27 2020
Journal Name
Journal Of Mechanics Of Continua And Mathematical Sciences
SUGGESTING MULTIPHASE REGRESSION MODEL ESTIMATION WITH SOME THRESHOLD POINT
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The estimation of the regular regression model requires several assumptions to be satisfied such as "linearity". One problem occurs by partitioning the regression curve into two (or more) parts and then joining them by threshold point(s). This situation is regarded as a linearity violation of regression. Therefore, the multiphase regression model is received increasing attention as an alternative approach which describes the changing of the behavior of the phenomenon through threshold point estimation. Maximum likelihood estimator "MLE" has been used in both model and threshold point estimations. However, MLE is not resistant against violations such as outliers' existence or in case of the heavy-tailed error distribution. The main goal of t

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Publication Date
Thu Oct 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
Estimation Multivariate data points in spatial statistics with application
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This paper  deals  to how to estimate points non measured spatial data when the number of its terms (sample spatial) a few, that are not preferred for the estimation process, because we also know that whenever if the data is large, the estimation results of the points non measured to be better and thus the variance estimate less, so the idea of this paper is how to take advantage of the data other secondary (auxiliary), which have a strong correlation with the primary data (basic) to be estimated single points of non-measured, as well as measuring the variance estimate, has been the use of technique Co-kriging in this field to build predictions spatial estimation process, and then we applied this idea to real data in th

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