Preferred Language
Articles
/
joe-575
Estimating Angle of Arrival (AOA) for Wideband Signal by Sensor Delay Line (SDL) and Tapped Delay Line (TDL) Processors
...Show More Authors

Angle of arrival (AOA) estimation for wideband signal becomes more necessary for modern communication systems like Global System for Mobile (GSM), satellite, military applications and spread spectrum (frequency hopping and direct sequence). Most of the researchers are focusing on how to cancel the effects of signal bandwidth on AOA estimation performance by using a transversal filter (tap delay line) (TDL). Most of the researchers were using two elements array antenna to study these effects. In this research, a general case of proposed (M) array elements is used. A transversal filter (TDL) in phase adaptive array antenna system is used to calculate the optimum number of taps required to compensate these effect. The proposed system uses a phase adaptive array antenna in conjunction with LMS algorithm to work an angle of arrival (AOA) estimator for wideband signals rather than interference canceller. An alternative solution to compensate for the effect of signal bandwidth is proposed by using sensor delay line (SDL) instead of fixed delay unit since it has variable time sampling in the time domain and not fixed time delay, depending on the angle of arrival of received signals. The proposed system has the ability to estimate two parameters for received signals simultaneously (the output Signal to Noise Ratio (SNR) and AOA), unlike others systems which estimate AOA only. The comparison of the simulation results with Multiple Signal Classification (MUSIC) technique showed that the proposed system gives good results for estimating AOA and the output SNR for wideband signals. (SDL) processor shows better performance result than (TDL) processor. MUSIC technique with both (SDL) and (TDL) processors shows unacceptable results for estimating (AOA) for the wideband signal.  

 

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Sep 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Certain Assessment of Using MWCNT Nps in Drilling Fluid to Mitigate Stick-Slip Problem during Drilling Operation System
...Show More Authors

   Stick- slip is the continuous stopping& release of the Bit/BHA due to the irregular down-hole rotation prompted by the existing relationship between the friction torque and the torque applied from the surface to free the bit.

   Friction coefficient between BHA and wellbore is the main player of stick slip amount, which can be mitigated by support a good lubricators as additives in drilling mud.

   Mathematical (or empirical) solves should be done through adjusting all parameters which supposed to reduce stick- slip as low as possible using different models, one of the main parameters is drilling mud. As per Nanoparticles drilling fluid is a new technology that offers high performance

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Wed Nov 14 2018
Journal Name
Fiber And Integrated Optics
Design Investigation of 2 × 2 Mach–Zehnder Optical Switch Based on a Metal–Polymer–Silicon Hybrid Plasmonic Waveguide
...Show More Authors

In this paper, a miniaturized 2 × 2 electro-optic plasmonic Mach– Zehnder switch (MZS) based on metal–polymer–silicon hybrid waveguide is presented. Adiabatic tapers are designed to couple the light between the plasmonic phase shifter, implemented in each of the MZS arms, and the 3-dB input/output directional couplers. For 6 µm-long hybrid plasmonic waveguide supported by JRD1 polymer (r33= 390 pm/V), a π-phase shift voltage of 2 V is obtained. The switch is designed for 1550 nm operation wavelength using COMSOL software and characterizes by 2.3 dB insertion loss, 9.9 fJ/bit power consumption, and 640 GHz operation bandwidth

View Publication
Scopus (5)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Tue Sep 14 2021
Journal Name
Research Journal Of Pharmacy And Technology
The Isolation of specifically lytic phages along with their extracted endolysins as antibacterial agents to MDR Enterococcus faecalis
...Show More Authors

Background: Multidrug-resistant (MDR) enterococci have become a major problem in recent times and have been reported increasingly around the world. Lytic phages infect bacteria leading to rapid host death with limited risk of phage transduction, underlining the increasing interest in potential phage therapy in the future. Objective (s): The aim of this study is to use phage therapy as alternative approach for treatment of Enterococcus faecalis infections that recorded as MDR in Iraq to tackle this problem. Materials and Methods: Thirty E. faecalis isolates were collected from patients with different infectious diseases such as urinary tract infection (UTI), diabetic foot, septicemia, and wound infections. The isolation of specific l

... Show More
View Publication
Scopus (7)
Crossref (3)
Scopus Crossref
Publication Date
Tue Sep 01 2015
Journal Name
Journal Of Engineering
Study Effect of Central Rectangular Perforation on the Natural Convection Heat Transfer in an Inclined Heated Flat Plate
...Show More Authors

Anumerical solutions is presented to investigate the effect of inclination angle (θ) , perforation ratio (m) and wall temperature of the plate (Tw) on the heat transfer in natural convection from isothermal square flat plate up surface heated (with and without concentrated hole). The flat plate with dimensions of (128 mm) length × (64 mm) width has been used five with square models of the flat plate that gave a rectangular perforation of (m=0.03, 0.06, 0.13, 0.25, 0.5). The values of angle of inclination were (0o, 15o 30o 45o 60o) from horizontal position and the values of wall temperature (50oC, 60 oC, 70 oC, 90 oC, 100o<

... Show More
View Publication Preview PDF
Publication Date
Wed Jan 01 2014
Journal Name
The Scientific World Journal
Heat Transfer Enhancement of Laminar Nanofluids Flow in a Circular Tube Fitted with Parabolic-Cut Twisted Tape Inserts
...Show More Authors

Numerical investigation has been carried out on heat transfer and friction factor characteristics of copper-water nanofluid flow in a constant heat-fluxed tube with the existence of new configuration of vortex generator using Computational Fluid Dynamics (CFD) simulation. Two types of swirl flow generator: Classical twisted tape (CTT) and Parabolic-cut twisted tape (PCT) with a different twist ratio (y= 2.93, 3.91 and 4.89) and different cut depth (w= 0.5, 1.0 and 1.5 cm) with 2% and 4% volume concentration

... Show More
View Publication
Scopus (38)
Crossref (30)
Scopus Clarivate Crossref
Publication Date
Sun May 10 2020
Journal Name
Baghdad Science Journal
Temperature Impacts on the Cardiac Activity of the Snail Pomacea canaliculata from Shatt Al-Arab Region, Basrah, Iraq
...Show More Authors

The effects of temperature on an exotic aquatic snail Pomacea canaliculata  (Lamarck, 1819) collected from the Shatt Al-Arab intertidal zone were investigated. A series of laboratory experiments were conducted during the summer period of 2017. Individuals of new born snails hatched in the laboratory from adult snails were collected from Shatt Al-Arab intertidal zone, and subjected to five fixed temperatures: 15, 25, 35, 40 and 45 Cº, after short term thermal acclimation. The heartbeats (HB) were counted at each temperature level. The results showed significant  direct increase of HB from 15 Cº (19.8 HB/min) up to 25 Cº (76 HB/min) (P<0.05)  as well as from 25 Cº to 35 Cº (93 HB/min). At 40 Cº the snail HB

... Show More
View Publication Preview PDF
Scopus (2)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Fri Apr 07 2017
Journal Name
Oncology Letters
AURKA mRNA expression is an independent predictor of poor prognosis in patients with non-small cell lung cancer
...Show More Authors

View Publication
Scopus (35)
Crossref (29)
Scopus Clarivate Crossref
Publication Date
Sun Nov 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
NEW RECORD OF THE Genus Pullimosina Roháček, 1983 (DIPTERA, Sphaeroceridae) FROM KERBALA CITY, IRAQ, Study in Forensic Entomology
...Show More Authors
Abstract<p>This study aims to know the types of insects belonging to the Sphaeroceridae family. During this study, one species registered for this family for the first time to Iraq (New genus and species). It is using two methods of killing are injurious machine (knife) and toxic substance (strychnine). Four areas within Karbala governorate studied and identified to know their spread and time of presence on the body during the stages of decomposition. During this experiment, the bodies of dogs used to identify types of insects attracted to the body during four seasons. The results indicated the presence of the species <italic>Pullimosina heteroneura</italic> (Haliday, 1836) in the firs</p> ... Show More
View Publication
Scopus (3)
Crossref (2)
Scopus Crossref
Publication Date
Thu Apr 18 2019
Journal Name
Al-kindy College Medical Journal
Maternal knowledge related to anemia during pregnancy among a sample of mothers attending Primary Health Care centers. Baghdad.
...Show More Authors

Background: Anaemia is a major public health concern and is one of the most prevalent health issue in women within reproductive age group.

Objective: to assess maternal knowledge related to anaemia during pregnancy.

Type of the study: A cross –sectional study.

Method: The study including 200 mothers who attended selected primary health care centres, Baghdad during November and December 2015, they completed a previously prepared questionnaire coveringsocio-demographic characteristics and knowledge regarding anaemia in 4 main domains. The responses were analysed by using frequency, percentage and percent score for each statement a

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sat Aug 30 2025
Journal Name
Gsc Biological And Pharmaceutical Sciences
A new record of North African catfish Clarias gariepinus (Burchell, 1822) (Siluriformes: Clariidae) in Baghdad from Tigris River
...Show More Authors

A single specimen of the African catfish, Clarias gariepinus, was recorded for the first time in Baghdad, Iraq. The specimen was caught during a fish survey to document some local species in northern Baghdad (Al-Rusafa) on March 21, 2023. The total length of the specimen was 43 cm, and its weight was 590 grams. Some biometric measurements of the specimen were studied and found to be consistent with the general characteristics of the African catfish Clarias gariepinus (Burchell, 1822). It is possible that the fish entered Iraqi inland waters, specifically from the Euphrates River via Syria or from the Tigris River via Turkey.

View Publication
Crossref