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alkej-170
Estimation of SNR Including Quantization Error of Multi-Wavelength Lidar Receiver
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 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 receivers were presented while averaging together 1, 20, 50 and 100 lidar returns and combined to the signal to noise ratio associated with the quantization process for each channel.

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Publication Date
Wed Jul 01 2020
Journal Name
Journal Of Engineering
Study the Effect of Catalyst -to- Oil Ratio Parameter (COR) on Catalytic Cracking of Heavy Vacuum Gas Oil
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This work deals with the production of light fuel cuts of (gasoline, kerosene and gas oil) by catalytic cracking treatment of secondary product mater (heavy vacuum gas oil) which was produced from the vacuum distillation unit in any petroleum refinery. The objective of this research was to study the effect of the catalyst -to- oil ratio parameter on catalytic cracking process of heavy vacuum gas oil feed at constant temperature (450 °C). The first step of this treatment was, catalytic cracking of this material by constructed batch reactor occupied with auxiliary control devices, at selective range of the catalyst –to- oil ratio parameter (  2, 2.5, 3 and 3.5) respectively.  The conversion of heavy vacuum gas

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Publication Date
Thu Aug 30 2018
Journal Name
Iraqi Journal Of Science
Seismic Data Processing of Subba Oil Field in South Iraq
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Evaluation study was conducted for seismic interpretation using two-dimensional seismic data for Subba oil field, which is located in the southern Iraq. The Subba oil field was discovered in 1973 through the results of the seismic surveys and the digging of the first exploratory well SU-1 in 1975 to the south of the Subba oil field. The entire length of the field is 35 km and its width is about 10 km. The Subba oil field contains 15 wells most of them distributed in the central of the field.

     This study is dealing with the field data and how to process it for the purpose of interpretation; the processes included conversion of field data format, compensation of lost data and noise disposal, as well as the a

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Publication Date
Tue Jan 18 2022
Journal Name
Iraqi Journal Of Science
Restoration of Digital Images Using an Iterative Filter Algorithm
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Digital image started to including in various fields like, physics science, computer science, engineering science, chemistry science, biology science and medication science, to get from it some important information. But any images acquired by optical or electronic means is likely to be degraded by the sensing environment. In this paper, we will study and derive Iterative Tikhonov-Miller filter and Wiener filter by using criterion function. Then use the filters to restore the degraded image and show the Iterative Tikhonov-Miller filter has better performance when increasing the number of iteration To a certain limit then, the performs will be decrease. The performance of Iterative Tikhonov-Miller filter has better performance for less de

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Publication Date
Sun Dec 01 2002
Journal Name
Iraqi Journal Of Physics
Preparation of thin films of SiCN from gas-phase reaction induced by TEA-CO2 laser and study of their optical properties
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In this paper, silicon carbonitried thin films were prepared by the method of photolysis of the silane (SiH4) and ethylene (C2H4) gases, with and without ammonia gas (NH3), which is represented by the ratio between the (PNH3) and (PSiH4 + PC2H4 + PNH3), (which assign by the letter X), X has the values (0, 0.13, 0.33). This method carried out by using TEA-CO2 laser, on glass substrate at (375 oC), deposition rate (0.416-0.833) nm/pulse thin film thickness of (500-1000) nm. The optical properties of the films were studied by using Absorbance and Transmittance spectrums in wavelength range of (400-1100) nm, the results showed that the electronic transitions is indirect and the energy gap for the SiCN films increase with increasing of nitrog

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Publication Date
Wed May 17 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Mathematical Model of Effect of Number of Pulses of Pulsed Laser on Formation Process of Plasma
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The effect of number of pulses of pulsed laser on materials is studied analytically, different pulses has been used with the same delay time.  The depth of possible damage to the surface of copper and titanium as well as depth of the crater to both materials were considered in this study.  The study revealed that linear model is only possible when estimating depth of possible damage for copper material, this means that the depth of possible damage increases with the increment of number of laser pulses .As for titanium material, it is found  the relationship is nonlinear.  The depth of possible damage of titanium and copper is not the same, and copper seems to be more predictable than titanium.  
 

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Publication Date
Thu Dec 23 2021
Journal Name
Iraqi Journal Of Science
Noise Reduction, Enhancement and Classification for Sonar Images
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    Ultrasound imaging has some problems with image properties output. These affects the specialist decision. Ultrasound noise type is the speckle noise which has a grainy pattern depending on the signal. There are two parts of this study. The first part is the enhancing of images with adaptive Weiner, Lee, Gamma and Frost filters with 3x3, 5x5, and 7x7 sliding windows. The evaluated process was achieved using signal to noise ratio (SNR), peak signal to noise ratio (PSNR), mean square error (MSE), and maximum difference (MD) criteria. The second part consists of simulating noise in a standard image (Lina image) by adding different percentage of speckle noise from 0.01 to 0.06. The supervised classification based minimum di

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Publication Date
Thu Jan 20 2022
Journal Name
Journal Of Clinical Medicine
Comparison of the Safety and Efficacy of Laser Versus Pneumatic Intracorporeal Lithotripsy for Treatment of Bladder Stones in Children
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This study aimed to compare the safety and efficacy of laser lithotripsy and pneumatic lithotripsy, the two most commonly used transurethral lithotripsy methods for treating bladder stones in children in Iraq. Between January 2013 and December 2016, 64 children with bladder stones were included in this prospective randomized study, after ethical committee approval and written consent from the children’s parents or caregivers were obtained. Patients were assigned randomly by computer software to two groups treated with either pneumatic cystolithotripsy or laser lithotripsy. A 9 Fr. semirigid ureteroscope was used to pass the lithotripter through and fragment the stone. A catheter of 8–12 Fr. was then introduced and kept in place

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Publication Date
Fri Dec 01 2023
Journal Name
Baghdad Science Journal
Simultaneous Determination of Binary Mixture of Estradiol and Progesterone Using Different Spectrophotometric Methods
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Four rapid, accurate and very simple derivative spectrophotometric techniques were developed for the quantitative determination of binary mixtures of estradiol (E2) and progesterone (PRG) formulated as a capsule. Method I is the first derivative zero-crossing technique, derivative amplitudes were detected at the zero-crossing wavelength of 239.27 and 292.51 nm for the quantification of estradiol and 249.19 nm for Progesterone. Method II is ratio subtraction, progesterone was determined at λmax 240 nm after subtraction of interference exerted by estradiol. Method III is modified amplitude subtraction, which was established using derivative spectroscopy and mathematical manipulations. Method IIII is the absorbance ratio technique, absorba

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Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
A comparative study of the effects of argon laser and continuous Nd: YAG laser on blood vessel
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Several types of laser are used in experimental works in order to study the effects of laser on blood vessel. They differ from each other by a lot of properties mainly in wavelength, energy of the laser and pulse duration. In this study argon laser (488 nm- 514 nm) and continuous Nd: YAG laSer (1064 nm), have been applied to 50 samples of sheep blgod tesselS. Histologically, tha results of the study were different According to the txpe of L`sar used; apgon larer had distrabtave effects on $he blood vessal while continuous Nd: YAG laser Appeaped to be the safesd one on the blmod vessel architecture. This study concluded that argoj laser has da-aging ef&ect on

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Publication Date
Sun Jan 30 2022
Journal Name
Iraqi Journal Of Science
Effects of Vitamin D Deficiency in Polycystic Ovarian Syndrome
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    Polycystic ovary syndrome is a very common cause of female infertility. This study aims to assess the prevalence of vitamin D deficiency and its association with clinical and anthropometric characteristics of Iraqi women with and without polycystic ovary syndrome. Fifty eightwomen with the disease and their matched control group were included. Their blood pressure was measured. Serum level of 25 hydroxy vitamin D of <20 ng/mL was graded as vitamin D deficiency. The polycystic ovary syndrome group had significantly lower levels of 25 hydroxy vitamin D, higher body mass index, and higher waist to hip ratio in contrast to the control group. The difference in body mass index was more significant in the obese category. W

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