Preferred Language
Articles
/
qBf1-40BVTCNdQwCpCvl
HF Wave Propagation Prediction Based On Passive Oblique Ionosonde
...Show More Authors

High frequency (HF) communications have an important role in long distances wireless communications. This frequency band is more important than VHF and UHF, as HF frequencies can cut longer distance with a single hopping. It has a low operation cost because it offers over-the-horizon communications without repeaters, therefore it can be used as a backup for satellite communications in emergency conditions. One of the main problems in HF communications is the prediction of the propagation direction and the frequency of optimum transmission (FOT) that must be used at a certain time. This paper introduces a new technique based on Oblique Ionosonde Station (OIS) to overcome this problem with a low cost and an easier way. This technique uses the international shortwave radio stations and the global beacons as the OIS transmitter and a normal HF receiver as the OIS receiver to verify the direction of propagation and the FOT. In addition, the critical frequency for F2 layer (fof2) was estimated in this paper for Iraq experimentally. The proposed technique was tested practically, and FOT range between Baghdad and other remote stations was estimated successfully using a radio receiver from Kenwood model R 1000 with a long wire antenna as a passive OIS system receiver.

Scopus
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Jun 01 2021
Journal Name
Journal Of The College Of Languages (jcl)
The passive of verbs constructed with prepositions: Das Passiv der mit Präpositionen konstruierten Verben
...Show More Authors

 Verbs in German and Arabic are of two types: active and passive. Passive voice  is a grammatical voice construction that is found in many languages.  Out of grammatical perspective, each main verb has a form in the active and one in the passive known as a "genus verbi" (type of verb). In passive voice, both in German and in Arabic, the focus is on the action itself or on the result of the action; often the perpetrator is not mentioned. In German, to conjugate verbs in the passive voice, you must know the forms of werden (to become). German uses werden  + the past participle and states it at the end of a sentence. In Arabic,

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Jan 01 1990
Journal Name
Solar & Wind Technology
Use of passive heat transfer and fluorescence to improve performance of photovoltaic solar panels
...Show More Authors

View Publication
Crossref (1)
Scopus Crossref
Publication Date
Wed Jun 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Compared with Genetic Algorithm Fast – MCD – Nested Extension and Neural Network Multilayer Back propagation
...Show More Authors

The study using Nonparametric methods for roubust to estimate a location and scatter it is depending  minimum covariance determinant of multivariate regression model , due to the presence of outliear values and increase the sample size and presence of more than after the model regression multivariate therefore be difficult to find a median location .       

It has been the use of genetic algorithm Fast – MCD – Nested Extension and compared with neural Network Back Propagation of multilayer in terms of accuracy of the results and speed in finding median location ,while the best sample to be determined by relying on less distance (Mahalanobis distance)has the stu

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Aug 01 2015
Journal Name
2015 37th Annual International Conference Of The Ieee Engineering In Medicine And Biology Society (embc)
Wave speed and reflections proximal to aneurism and stenosis of flexible tubes
...Show More Authors

Arterial aneurism and stenosis are disorders that lead to circulation malfunction. Stenosis often leads to hypoxia of the organ depending on the affected artery, whilst aneurism can lead to dissection with known lethal consequences. On both cases, the pulse wave produced by the contracting heart is reflected at these discontinuities, and estimating the size of these reflected waves using wave intensity analysis (WIA) is the main aim of this work. We also aim to measure wave speed, or pulse wave velocity (PWV) as more commonly known within the discontinuities. We manufactured 4 stenosis and 4 aneurism silicon sections, connected one at a time to a mother tube, and tested in vitro. Pressure and flow were measured proximal to the discontinuity

... Show More
View Publication
Scopus (3)
Crossref (1)
Scopus Crossref
Publication Date
Thu Apr 27 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Measurement of Electromagnetic wave Emitted from Home Appliance by Milligauss meter
...Show More Authors

   The appliance of milligauss meter was designed by Qusay Ismail to measure the induce of electromagnetic field for home appliance which are put at a distance from milligauss meter (15-30-60)cm .The results showed some appliance has recorded higher than normal acceptable level of electromagnetic radiation emissions and produced radiation of (350650)milligauss as for the rest of appliances has recorded values which are ranged between (1200)milligauss ,laptop was recorde radiation generally lower than from desktop and computer moniter (CRT).The radiation ,intensity decrease with increasing distance.

View Publication Preview PDF
Publication Date
Mon Jun 01 2015
Journal Name
International Photonics And Optoelectronics
Canonical Logic Units using Bidirectional Four-Wave Mixing in Highly Nonlinear Fiber
...Show More Authors

All-optical canonical logic units at 40 Gb/s using bidirectional four-wave mixing (FWM) in highly nonlinear fiber are proposed and experimentally demonstrated. Clear temporal waveforms and correct pattern streams are successfully observed in the experiment. This scheme can reduce the amount of nonlinear devices and enlarge the computing capacity compared with general ones. The numerical simulations are made to analyze the relationship between the FWM efficiency and the position of two interactional signals. © 2015 Chinese Laser Press

View Publication
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Wed Sep 11 2019
Journal Name
Aip Conference Proceedings
Estimation of shock wave position in plasma plume using Sedov-Taylor model
...Show More Authors

In this work, radius of shock wave of plasma plume (R) and speed of plasma (U) have been calculated theoretically using Matlab program.

Publication Date
Thu Dec 27 2018
Journal Name
International Journal Of Hydrogen Energy
Compressional wave velocity of hydrate-bearing bentheimer sediments with varying pore fillings
...Show More Authors

A potential alternative energy resource to meet energy demands is the vast amount of gas stored in hydrate reserves. However, major challenges in terms of exploration and production surround profitable and effective exploitation of these reserves. The measurement of acoustic velocity is a useful method for exploration of gas hydrate reserves and can be an efficient method to characterize the hydrate-bearing sediments. In this study, the compressional wave velocity (P-wave velocity) of consolidated sediments (Bentheimer) with and without tetrahydrofuran hydrate-bearing pore fillings were measured using the pulse transmission method. The study has found that the P-wave velocity of consolidated sediments increase with increasing hydrate format

... Show More
Scopus (47)
Crossref (42)
Scopus Clarivate Crossref
Publication Date
Thu Jul 01 2021
Journal Name
Solar Energy
A new approach for employing multiple PCMs in the passive thermal management of photovoltaic modules
...Show More Authors

View Publication
Scopus (99)
Crossref (91)
Scopus Clarivate Crossref
Publication Date
Tue Sep 01 2015
Journal Name
Journal Of Engineering
Application of Box-Behnken Method Based ANN-GA to Prediction of wt.% of Doping Elements for Incoloy 800H Coated by Aluminizing-Chromizing
...Show More Authors

In this work , an effective procedure of Box-Behnken based-ANN (Artificial Neural Network) and GA (Genetic Algorithm) has been utilized for finding the optimum conditions of wt.% of doping elements (Ce,Y, and Ge) doped-aluminizing-chromizing of Incoloy 800H . ANN and Box-Behnken design method have been implanted for minimizing hot corrosion rate kp (10-12g2.cm-4.s-1) in Incoloy 800H at 900oC . ANN was used for estimating the predicted values of hot corrosion rate kp (10-12g2.cm-4.s-1) . The optimal wt.% of doping elements combination to obtain minimum hot corrosion rate was calculated using genetic alg

... Show More
View Publication Preview PDF