Preferred Language
Articles
/
ijs-7688
Electron Density Estimation by Electrostatic Probe for Plasma Generated Near the Spacecraft Returning to the Earth's Atmosphere
...Show More Authors

     In this work, the electrostatic probe was utilized to estimate the density of electrons for plasma generated around reentry vehicles that have a geometrically blunt nose at high-altitude. The thermocouple uses to measured electron temperature, which is equal to the temperature of the gas, on board the MAC spacecraft. In the spacecraft backflow field, electrostatic probe measurements were taken at five separate regions 1 to 5 cm from the body of the spacecraft. Over an altitude range of 90 to 50 km with an electron density of 108 to 1012 1/cm3, respectively. The measured electron temperature ranged from 0.05 to 0.9 electron volts and the maximum re-entry velocity of the spacecraft was about 7048 m/s in the re-entry experiment. The cooling using water jet in the flow field, the relationship between electron density, angle of attack changes, and the combustion products of the spacecraft's nose is also discussed.

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Oct 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Qualitative and Quantitative Estimation of Total Phenols in Narcissus tazettaL. Bulbs
...Show More Authors

Narcissus tazetta, a member of the Amaryllidaceae family, is known to be rich in bioactive metabolites such as alkaloids, phenolics and flavonoids, which have been found in nearly every species in this family. N. tazetta cultivated in Iraq, had not previously been studied for its active components; thus, the current study used phytochemical screening and phenolic compounds estimation, both qualitatively and quantitatively. Results showed that the plant alcoholic extract was rich in alkaloids, polyphenols and flavonoids besides tannins, polysaccharides and saponins. Qualitatively; TLC and HPLC chromatogram for total phenolics and flavonoids compounds revealed the presence of Gallic acid (GA), Caffeic acid (CA), Paracumar

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Jun 21 2022
Journal Name
Journal Of Planner And Development
Estimation of Traffic Volumes Distribution of Urban Streets in Baghdad City
...Show More Authors

The aim of this research is to explore the time and space distribution of traffic volume demand and investigate its vehicle compositions. The four selected links presented the activity of transportation facilities and different congestion points according to directions. The study area belongs to Al-Rusafa sector in Baghdad city that exhibited higher rate of traffic congestions of working days at peak morning and evening periods due to the different mixed land uses. The obtained results showed that Link (1) from Medical city intersection to Sarafiya intersection, demonstrated the highest traffic volume in both peak time periods morning AM and afternoon PM where the demand exceeds the capacity along the link corridor. Also, higher values f

... Show More
View Publication Preview PDF
Publication Date
Mon Jan 23 2023
Journal Name
The Egyptian Journal Of Hospital Medicine
Estimation of SLC25A3 Gene Expression in Chronic Myelogenous Leukemia Iraqi Patients
...Show More Authors

Background: Chronic myelogenous leukemia is a malignant hematological disease of hematopoietic stem cells. It is difficult to adapt treatment to each patient's risk level because there are currently few clinical tests and no molecular diagnostics that may predict a patient's clock for the advancement of CML at the time of chronic phase diagnosis. Biomarkers that can differentiate people based on the outcome at diagnosis are needed for blast crisis prevention and response improvement. Objective: This study is an effort to exploit the SLC25A3 gene as a potential biomarker for CML. Methods: RT-qPCR was applied to assess the expression levels of the SLC25A3 gene. Results: In comparison to the mean ΔCt of the control group, which was found to b

... Show More
Publication Date
Fri Feb 01 2013
Journal Name
Journal Of Engineering
Estimation of Flexural Strength of Plain Concrete from Ultrasonic Pulse Velocity
...Show More Authors

The aim of this study is to propose mathematical expressions for estimation of the flexural strength of plain concrete members from ultrasonic pulse velocity (UPV) measurements. More than two hundred pieces of precast concrete kerb units were subjected to a scheduled test program. The tests were divided into two categories; non-destructive ultrasonic and bending or rupture tests. For each precast unit, direct and indirect (surface) ultrasonic pulses were subjected to the concrete media to measure their travel velocities. The results of the tests were monitored in two graphs so that two mathematical relationships can be drawn. Direct pulse velocity versus the flexural strength was given in the first relationship while the second equation des

... Show More
Publication Date
Mon Feb 20 2017
Journal Name
Proceedings Of The 5th International Conference On Communications And Broadband Networking
Bit precision and Cyclic prefix effect on OFDM Power Consumption Estimation
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Fri Jan 01 2016
Journal Name
Journal Of Engineering
Mobile position estimation using artificial neural network in CDMA cellular systems
...Show More Authors

Using the Neural network as a type of associative memory will be introduced in this paper through the problem of mobile position estimation where mobile estimate its location depending on the signal strength reach to it from several around base stations where the neural network can be implemented inside the mobile. Traditional methods of time of arrival (TOA) and received signal strength (RSS) are used and compared with two analytical methods, optimal positioning method and average positioning method. The data that are used for training are ideal since they can be obtained based on geometry of CDMA cell topology. The test of the two methods TOA and RSS take many cases through a nonlinear path that MS can move through that region. The result

... Show More
Publication Date
Thu May 25 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Numerical Estimation of Some Properties of Magnesium Aluminum Silicate Glass Ceramic
...Show More Authors

Magnesium aluminum silicate of glass ceramic having different amounts of magnesium fluoride in the range (0-13.2)%. Thermal expansion coefficient and micro hardness of the base glass and glass ceramic samples are seen to be interdependent but due to the multi – component system, the behaviour is seen to be somewhat complex, with an increase in Mg F2 content. The thermal expansion coefficient increase and micro harness decrease, numerical simulation of thermal expansion and hardness is useful in this study, L2 – regression is used to calculate the two parameters associated with each glass component, by comparing the measured parameters and the calculated parameters ,it is useful to use such a method to calculate the quantity

... Show More
View Publication Preview PDF
Publication Date
Sun Jun 30 2013
Journal Name
Al-khwarizmi Engineering Journal
Estimation of SNR Including Quantization Error of Multi-Wavelength Lidar Receiver
...Show More Authors

 This paper comprises the design and operation of mono-static backscatter lidar station based on a pulsed Nd: YAG laser that operates at multiple wavelengths. The three-color lidar laser transmitter is based on the collinear fundamental 1064 nm, second harmonic 532 nm and a third harmonic 355nm output of a Nd:YAG laser. The most important parameter of lidar especially daytime operations is the signal-to-noise ratio (SNR) which gives some instructions in designing of lidar and it is often limit the effective range. The reason is that noises or interferences always badly affect the measured results. The inversion algorithms have been developed for the study of atmospheric aerosols. Signal-to-noise ratio (SNR) of three-color channel re

... Show More
View Publication Preview PDF
Publication Date
Mon Jan 20 2020
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
On Estimation of P(Y<X) in Case Inverse Kumaraswamy Distribution
...Show More Authors

The estimation of the stressÙ€ strength reliability of Invers Kumaraswamy distribution will be introduced in this paper based on the maximum likelihood, moment and shrinkage methods. The mean squared error has been used to compare among proposed estimators. Also a Monte Carlo simulation study is conducted to investigate the performance of the proposed methods in this paper.

View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Fri Jan 01 2016
Journal Name
Journal Of Engineering
Mobile Position Estimation using Artificial Neural Network in CDMA Cellular Systems
...Show More Authors

Using the Neural network as a type of associative memory will be introduced in this paper through the problem of mobile position estimation where mobile estimate its location depending on the signal strength reach to it from several around base stations where the neural network can be implemented inside the mobile. Traditional methods of time of arrival (TOA) and received signal strength (RSS) are used and compared with two analytical methods, optimal positioning method and average positioning method. The data that are used for training are ideal since they can be obtained based on geometry of CDMA cell topology. The test of the two methods TOA and RSS take many cases through a nonlinear path that MS can move through tha

... Show More
View Publication Preview PDF