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Effect of optimal shot peening time on fatigue life for aluminum alloy 6061-T651
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The compressive residual stresses generated by shot peening, is increased in a direct proportional way with shot peening time (SPT). For each metal, there is an optimum shot peening time (O.S.T) which gives the optimum fatigue life. This paper experimentally studied to optimize shot peening time of aluminium alloy 6061-T651 as well as using of and analysis of variance (ANOVA).

Two types of fatigue test specimens’ configuration were used, one without notch (smooth) and the other with a notch radius (1,25mm), each type was shot peened at different time. The (O.S.T) was experimentally estimated  to be 8 minutes reaching the surface stresses at maximum peak of -184.94 MPa.

A response surface methodology (RSM) is presented to optimize the surface properties of fatigue life due to effect of two parameters (shot peening time and fatigue stresses). A statistical software was used to perform analysis of variance (ANOVA)  to predict the optimum shot peening time. The results were 8.007 minutes without notch and 7.53 minutes with notch. Two 2nd degree polynomials were obtained for the two studied cases with confidence level of 95%. Experimentally26.67% enhancement in fatigue life was obtained, but after using (RSM), the results gave 61% improvement, compared with ref. [2].

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Publication Date
Fri Feb 13 1998
Journal Name
المجلة العراقية للاحياء المجهرية
EFFECT OF SALTS CONCENTRATIONS AND CARBON SOURCES ON THE GROWTH OF EXTREMELY HALOPHILIC BACTERIA, GENUS Halobacterium
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ABSTRACT The isolation and characterization of (27) isolate of extreme halophilic bacteria was performed ninteen isolate belonged to the genus Halobacterium which included Hb.halobium. Hb. salinarium, Hb. volcanii. Growth curve and generation time in logarthmic phase was measured and found to be (12.8hr±0.32), (11.2hr±0.2), (9.8hr±0.87), respectivaly. Effect of various concentrations of NaCl, KCI, NH4Cl and MgSO4.7H2O was studied, NaCl was essential for the rod shape rapid growth Rat and pigmentation. Less than 1% concentration caused lysis of bacteria. Yeast extract was the best carbone source as compared with glucose and casamino acid.

Publication Date
Thu May 18 2023
Journal Name
Journal Of Engineering
Optimal Dimensions of Small Hydraulic Structure Cutoffs Using Coupled Genetic Algorithm and ANN Model
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A genetic algorithm model coupled with artificial neural network model was developed to find the optimal values of upstream, downstream cutoff lengths, length of floor and length of downstream protection required for a hydraulic structure. These were obtained for a given maximum difference head, depth of impervious layer and degree of anisotropy. The objective function to be minimized was the cost function with relative cost coefficients for the different dimensions obtained. Constraints used were those that satisfy a factor of safety of 2 against uplift pressure failure and 3 against piping failure.
Different cases reaching 1200 were modeled and analyzed using geo-studio modeling, with different values of input variables. The soil wa

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Publication Date
Tue Dec 01 2020
Journal Name
Journal Of Economics And Administrative Sciences
Select the optimal project by using two methods of analytic hierarchy and goal programming
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      The aim of this research is to solve a real problem in the Department of Economy and Investment in the Martyrs establishment, which is the selection of the optimal project through specific criteria by experts in the same department using a combined mathematical model for the two methods of analytic hierarchy process and goal programming, where a mathematical model for goal programming was built that takes into consideration the priorities of the goal criteria by the decision-maker to reach the best solution that meets all the objectives, whose importance was determined by the hierarchical analysis process. The most important result of this research is the selection of the second pro

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Publication Date
Sat Feb 09 2019
Journal Name
Journal Of The College Of Education For Women
Comparative Study of Image Denoising Using Wavelet Transforms and Optimal Threshold and Neighbouring Window
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NeighShrink is an efficient image denoising algorithm based on the discrete wavelet
transform (DWT). Its disadvantage is to use a suboptimal universal threshold and identical
neighbouring window size in all wavelet subbands. Dengwen and Wengang proposed an
improved method, which can determine an optimal threshold and neighbouring window size
for every subband by the Stein’s unbiased risk estimate (SURE). Its denoising performance is
considerably superior to NeighShrink and also outperforms SURE-LET, which is an up-todate
denoising algorithm based on the SURE. In this paper different wavelet transform
families are used with this improved method, the results show that Haar wavelet has the
lowest performance among

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Publication Date
Tue Dec 01 2020
Journal Name
Propulsion And Power Research
Heat transfer enhancement from heat sources using optimal design of combined fins heat-sinks
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Publication Date
Wed Dec 27 2017
Journal Name
Al-khwarizmi Engineering Journal
The Effect of Restriction Shape On Laminar Natural Convection Heat Transfer In A Vertical Circular Tube
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Natural convection heat transfer is experimentally investigated for laminar air flow in a vertical circular tube by using the boundary condition of constant wall heat flux in the ranges of (RaL) from (1.1*109) to (4.7*109). The experimental set-up was designed for determining the effect of different types of restrictions placed at entry of heated tube in bottom position, on the surface temperature distribution and on the local and average heat transfer coefficients. The apparatus was made with an electrically heated cylinder of a length (900mm) and diameter (30mm). The entry restrictions were included a circular tube of same diameter as the heated cylinder but with lengths of (60cm, 120cm), sharp-edge and

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Publication Date
Fri Sep 30 2011
Journal Name
Al-khwarizmi Engineering Journal
Charge Stratification and Fuel/Air Ratio Effect on the Efficiency of (ICADE) I. C. Engine Cycle
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The Isolated Combustion and Diluted Expansion (ICADE) internal combustion engine cycle combines the advantages of constant volume combustion of the Otto cycle with the high compression ratio of the Diesel cycle.   This work studies the effect of isolated air mass (charge stratification) on the efficiency of the cycle; the analysis shows that the decrease of isolated air mass will increase the efficiency of the cycle and the large dilution air mass will quench all NOx forming reactions and reduce unburned hydrocarbons. Furthermore, the effect of Fuel / Air ratio on the efficiency shows that the increase of Fuel / Air ratio will increase efficiency of the cycle.

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Publication Date
Wed Aug 30 2023
Journal Name
Baghdad Science Journal
Studying the Effect of COVID-19 on Liver Enzymes and Lipid Profile in Iraqi Recovering Patients
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  The Covid-19 virus disease has been shown to affect numerous organs and systems including the liver. The study aimed to compare lipid profiles and liver enzyme levels in individuals who had recovered from Covid-19 infection. To achieve the study objectives, liver Aspartate Aminotransferase (AST), Alanine Aminotransferase (ALT), Alkaline phosphatase (ALP),  Random Blood Sugar (RBS) and Lipid profile which include cholesterol, High-Density Lipoprotein (HDL), Triglycerides (T.G), Low-Density Lipoprotein (LDL), and Very low-density Lipoprotein (VLDL) were determined.

One hundred twenty serum samples were obtained, of which fifty samples were utilized as the control healthy persons (not affected by COVID) and seventy samples came f

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Publication Date
Thu Mar 30 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Effects of Different Concentrations of Melatonin on the Time-course of Nitrite–induced Oxidation of Hemoglobin: In vitro Study
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         Melatonin is a potent scavenger of reactive oxygen species or free radicals like superoxide and hydroxyl radicals. The oxidation of hemoglobin to methemoglobin (meth-Hb) by oxidizing compounds has been widely studied. The present work was designed to evaluate the ability of different concentrations of melatonin to inhibit nitrite–induced oxidation of hemoglobin. Blood samples were obtained from apparently healthy individuals from which erythrocyte hemolysate was prepared. Different concentrations of melatonin (10-9-1.0 mg/ml) were incubated for 10 min with the hemolysate, then to the resultant mixture 1 ml of sodium nitrite (final concentration 0.6 mM) was added, and the

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Publication Date
Tue Dec 06 2022
Journal Name
Iraqi National Journal Of Nursing Specialties
Evaluation of Nurses' Attitudes towards Patients’ End of life in Diyala Governorate
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Abstract:

Objectives: To assess nurses' attitude toward end of life phase. To find out  relationships between nurses attitude and socio demographic data (age, gender, level of education, years of experience).

Methodology: A descriptive cross-sectional study design is carried out to assess the attitude on nurses concerning patient at the end of life phase at critical care units, from the period of (1nd November 2021) to (1th February 2022). A probability sample random sampling technique used. Then, the number of participants in Baquba Teaching Hospital and general al khalis hospital were determined by using rando

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