Best estimation for the Reliability of 2-parameter Weibull Distribution

Sadeq M.  Jaafar; Baydaa I.  Abdulwahhab; Intasar A. Hasson

doi:10.21123/bsj.2009.6.4.705-710

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Publication Date

Sun Dec 06 2009

Journal Name

Baghdad Science Journal

Volume

6

Issue Number

4

DOI

10.21123/bsj.2009.6.4.705-710

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Best estimation for the Reliability of 2-parameter Weibull Distribution

"Weibull distribution

Reliability

Maximum Likelihood Method

White's Method

Newton-Raphson

Simulation."

Sadeq M. Jaafar

Baydaa I. Abdulwahhab

Intasar A. Hasson

...Show More Authors

This Research Tries To Investigate The Problem Of Estimating The Reliability Of Two Parameter Weibull Distribution,By Using Maximum Likelihood Method, And White Method. The Comparison Is done Through Simulation Process Depending On Three Choices Of Models (?=0.8 , ß=0.9) , (?=1.2 , ß=1.5) and (?=2.5 , ß=2). And Sample Size n=10 , 70, 150 We Use the Statistical Criterion Based On the Mean Square Error (MSE) For Comparison Amongst The Methods.

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Publication Date

Thu Jan 01 2009

Journal Name

Diala, Jour

Synthesis of Schiff bases of 2-thio-5-aryl-1,3,4- oxadiazole derivatives of possible biological activity

Schiff basesb

iological activity

1

3

4- oxadiazole

Eman M.

...Show More Authors

In this study, new derivatives of Schiff bases of 2-thio-5-aryl- 1,3,4-oxadiazole have been synthesized. The structures of these derivatives were characterized from their melting points, infrared spectroscopy and elemental analysis. The Schiff bases derivatives were tested for inhibition of E-coli and were all found to be active.

Publication Date

Fri May 01 2009

Journal Name

Diyala Journal For Pure Science

Synthesis of Schiff bases of 2-thio-5-aryl-1,3,4- oxadiazole derivatives of possible biological activity

Eman M.

Dheefaf F.

Wassan S.

...Show More Authors

In this study, new derivatives of Schiff bases of 2-thio-5-aryl1,3,4-oxadiazole have been synthesized. The structures of these derivatives were characterized from their melting points, infrared spectroscopy and elemental analysis. The Schiff bases derivatives were tested for inhibition of E-coli and were all found to be active.

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Publication Date

Sat Jul 20 2024

Journal Name

Al-rafidain Journal Of Medical Sciences ( Issn 2789-3219 )

Gender Distribution of Coronary Artery Calcium Score and Degree of Stenosis Assessed by Computed Tomography Angiography in Iraqi Patients with Chest Pain

Shaymaa

Ghasaq Ma'an

Saja Ali

Qays Ahmed

Mortadha

...Show More Authors

Background: Sex variations in coronary artery disease (CAD) are well documented. However, sex differences in coronary artery calcium (CAC) and its role in the detection of coronary artery stenosis remain controversial. Objective: To assess the impact of sex variation on coronary artery calcification and its efficacy in predicting coronary artery stenosis. Methods: This is a cross-sectional observational study including 230 consecutive patients with suspected CAD (120 men and 110 women) referred for coronary computed tomography angiography (CCTA). The study analyzed sex-based differences in the sensitivity and specificity of coronary artery calcification (CAC) for detecting moderate to severe stenosis across various coronary arteries

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Publication Date

Fri Sep 20 2024

Journal Name

Journal Of Nano Research

Impact of Copper Doping on Nanocrystalline SnO<sub>2</sub> Thin Films Synthesized by Sol-Gel Coating and Chemical Bath Deposition for Gas Sensor Applications

: Spin coating

SnO2 thin films

CBD

AFM

XRD

gas sensor

Selma M.H.

Mohammed

Isam M.

Amel S.

Abdulhussain K.

...Show More Authors

This work focuses on the preparation of pure nanocrystalline SnO2 and SnO2:Cu thin films on cleaned glass substrates utilizing a sol-gel spin coating and chemical bath deposition (CBD) procedures. The primary aim of this study is to investigate the possible use of these thin films in the context of gas sensor applications. The films underwent annealing in an air environment at a temperature of 500 ^◦C for duration of 60 minutes. The thickness of the film that was deposited may be estimated to be around 300 nm. The investigation included an examination of the structural, optical, electrical, and sensing characteristics, which were explored across various preparation circumstances, specifically focusing on varied

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(7)

Publication Date

Tue Jan 20 2026

Journal Name

Ibn Al-haitham Journal For Pure And Applied Sciences

Synthesis, Characterization and Dyeing Performance of Co(II), Ni(II), Cu(II) and Zn(II) Complexes with (E)-4-Chloro-N-(2-(Dimethylamino)Ethyl)-5-((8-Hydroxyquinolin-5-yl)Diazenyl)-2-Methoxybenzamide

5-Amino-4-chloro-N-(2-(dimethylamino)ethyl)-2-methoxybenz-amide

Azo dyes

Dyeing performance

Textile industry.

Amer J.

...Show More Authors

The (E)-4-chloro-N-(2-(dimethylamino)ethyl)-5-((8-hydroxy quinolin-5-yl)diazenyl)-2-methoxybenzamide azo ligand (L) has been synthesized through the reaction of diazonium salt for 5-amino-4-chloro-N-(2-(dimethylamino) ethyl)-2-methoxybenzamide with 8-hydroxyquinoline and identified azo ligand (L) using spectroscopic studies (FTIR, UV-Vis, 1H and 13CNMR, mass), and micro-elemental analysis (C.H.N). Metal chelates of Co(II), Ni(II), Cu(II), as well as Zn(II) have been completed as well as characterized using mass spectra, flame atomic absorption, elemental analysis (C.H.N), infrared, UV-Vis spectroscopy, as well as conductivity, magnetic measurements. The metal-to-ligand ratio in all complexes, as determined by analytical data, was 1:2 and ex

Publication Date

Fri Nov 29 2013

Journal Name

Arabian Journal Of Geosciences

Cd, Ni, and Pb distribution and pollution assessment in roadside dust from Baghdad City and Western Iraqi Desert

Salih

...Show More Authors

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(13)

Publication Date

Sun Nov 03 2002

Journal Name

University Of Baghdad

Parametric Study Of The Optimum Wing - Canard Configuration For The Swept Forward Fighter

Aerodynamics

CFD

Panel Method

Forward Swept Wing

Wing-Canard

Ahmed Tawfeeq Mustafa Ali

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The aerodynamic characteristics of the forward swept wing aircraft have been studied theoretically and an experimentally investigation for the wake field generated by this configuration have been carried out. Low order panel method with the Dirichlet boundary condition have been used to solve the case of the steady, inviscid and compressible flow. Two different panel method techniques have been employed: the source-doublet and the doublet method. The thickness for the various components was considered in the study. Prandtl-Glauert similarity rule has been used to account for the compressibility effects. Experimentally, a model was manufactured from wood with body length (290mm) and main wing span was (204mm). The primary objective of th

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Publication Date

Sat Sep 01 2018

Journal Name

Polyhedron

Novel dichloro (bis {2-[1-(4-methylphenyl)-1H-1, 2, 3-triazol-4-yl-κN3] pyridine-κN}) metal (II) coordination compounds of seven transition metals (Mn, Fe, Co, Ni, Cu, Zn and Cd)

The 1

3-dipolar cycloaddition “click” reaction between an azide and an alkyne to give a 1

2

3-triazole was reported by Huisgen in 1961 [1]. In 2002 the Copper(I)-catalyzed Azide-Alkyne Cycloaddition (CuAAC) to prepare a 1

2

3-triazole was reported [2]

[3]. The existence of relatively basic nitrogen atoms in the 1

2

3-triazole rings

and the possibility of introducing additional donor groups in the substituents (Fig. 1)

made the CuAAC “click” reaction an attractive method to prepare differently substituted 1

2

3-triazoles. These compounds have been used as ligands to coordinate to various metal ions that display a range of applications such as in electrochemical and photochemical studies

in supramolecular chemistry

magnetism

metal-ion sensing and catalysis [4]. The reasons for the success of the “click” reaction

is that it is easy to carry out and is widely applicable. It is not affected by a variety of functional groups

and can be carried out with a variety of Cu(I) catalysts and solvents

including aqueous conditions. The Cu(I) catalysts overcome the high activation energy barrier of the non-catalyzed Huisgen reaction by changing the mechanism of the reaction. A large variety of copper catalysts can be used for the CuAAC reaction

on condition that the maximum concentration of Cu(I) species is generated during the reaction. The pre-catalyst can be a Cu(II) salt (usually CuSO4) together with a reducing agent (often sodium ascorbate) or a Cu(I) compound in the presence of a base or amine ligand and a reducing agent to prevent oxidation to Cu(II). Some strong oxidising cupric salts or complexes such as Cu(OAc)2 also work. The solvent is very flexible from organic to aqueous

with the most commonly used combination water + an alcohol (t-BuOH

MeOH or EtOH). The key role of the solvent or solvent mixture is to solubilize the substrates and Cu(I) catalyst in order to ensure rapid reactions. Such aqueous conditions are very useful for biochemical conjugations

as well as for organic syntheses. We recently reported on the synthesis of a series of differently substituted 1

2

3-triazole chromophores

the substituted 2-(1-phenyl-1H-1

2

3-triazol-4-yl)pyridine ligands [5]

see Fig. 2 middle

with substituents R = H (L1)

CH3 (L2)

OCH3 (L3)

COOH

F

Cl

CN

CF3

O(CH2)3CH3 and N(CH3)2. These versatile ligands were found to coordinate to various first row transition metals

such as manganese

cobalt and nickel [6]. Here we extend the series to include more first row transition metal(II) coordination compounds

iron

copper and zinc

as well as a second row transition metal(II) coordination compound

cadmium

containing the 2-(1-(4-methyl-phenyl)-1H-1

2

3-triazol-1-yl)pyridine chromophore (Fig. 2 right with R = CH3). This series of seven novel coordination compounds is the first series of pyridyl-triazole based transition metal coordination compounds where seven different transition metals are coordinated to the same 1

2

3-triazole chromophore

namely 2-(1-(4-methyl-phenyl)-1H-1

2

3-triazol-1-yl)pyridine.

Kinaan M

...Show More Authors

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Publication Date

Sun Mar 13 2011

Journal Name

Baghdad Science Journal

Distribution Of Some Heavy Metals In Water,Sediment & Fish Cyprinus carpio in Euphrates River Near Al- Nassiriya City Center South Iraq .

Heavy metals

Water

Sediment

Fish

Euphrates River

Basim Y.

Awas B.

Afrah A.

...Show More Authors

The heavy metals Cd, Cu, Fe, pb, and Zn were determined in dissolved and particulate phases of the water,in addition to exchangeable and residual phases of the sediment and in the selected organs of the fish Cyprinus carpio collected from the Euphrates River near Al-Nassiriya city center south of Iraq during the summer period / 2009 .Also sediment texture and total organic carbon(TOC) were measured. Analysis emploing a flam Atomic Absorption Spectrophotometers . The mean regional concentrations of the heavy metals in dissolved (µg/l) and particulate phases (µg/gm) dry weight were Cd (0.15,16.13) ,Cu (0.59,24.48) ,Fe (726,909.4) ,Pb (0.20, 49.95) and Zn (2.5,35.62) respectively,and those for exchangeable and residual phases of the

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Publication Date

Sun Jun 05 2016

Journal Name

Baghdad Science Journal

Level and Statistical Distribution of Thyroid Peroxidase and Thyroid Hormones in Iraqi patients with Type1 Diabetes Mellitus at Al-Karkh Side

"BMI

FBS

T3

T4

TSH

Anti-TPO"

Sara S.

Sanad B.

Abass R.

...Show More Authors

Type 1 diabetes mellitus (T1DM) is an autoimmune disease frequently associated with autoimmune thyroid disease (AITD). The study is conducted at the Specialized Center for Endocrinology and Diabetes-Baghdad at Al-karkh side, during December 2013 up to April 2014. In this study, we investigate the prevalence of anti-thyroid peroxidase (anti-TPO) antibody in(80) type1 diabetic patients with (AITD) and (30) healthy controls .Blood samples are taken for investigation of thyroid tests by using Vitek Immunodiagnstic Assay System (VIDAS).Enzeme Linked Immunosorbent Assay (ELISA) is used to detect anti-thyroid antibody(anti-TPO). The results show that age, gender and BMI (body mass index) are similar in both groups, p>0.05. Among 80 type1 diabetic

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