Preferred Language
Articles
/
alkej-590
New Adaptive Data Transmission Scheme Over HF Radio
...Show More Authors

Acceptable Bit Error rate can be maintained by adapting some of the design parameters such as modulation, symbol rate, constellation size, and transmit power according to the channel state.

An estimate of HF propagation effects can be used to design an adaptive data transmission system over HF link. The proposed system combines the well known Automatic Link Establishment (ALE) together with variable rate transmission system. The standard ALE is modified to suite the required goal of selecting the best carrier frequency (channel) for a given transmission. This is based on measuring SINAD (Signal plus Noise plus Distortion to Noise plus Distortion), RSL (Received Signal Level), multipath phase distortion and BER (Bit Error Rate) for each channel in the frequency list. Channel condition evaluation is done by two arrangements. In the first an FFT analysis is used where a pilot signal is transmitted over the channel, while the data itself is used in the second arrangement. Passive channel assessment is used to avoid bad channels hence limiting the frequency pool size to be used in the point to point communication and the time required for  scanning and linking. An exchange of channel information between the transmitting and receiving stations is considered to select the modulation scheme for transmission. Mainly MPSK and MFSK are considered with different levels giving different data rate according to the channel condition. The results of the computer simulation have shown that when transmitting at a fixed channel symbol rate of 1200 symbol/sec, the information rate ranges from 2400 bps using 4FSK up to 3600 bps using 8PSK for SNR ranges from 11dB up to 26dB.

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Dec 28 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Science
Synthesis, Characterization and Biological Evaluation of New Dithiocarbamate Ligand and Its Complexes with some Metal Ions
...Show More Authors

New bidentate dithiocarbamate ligand (NaL) namely [Sodium-2-(((3-methyl -4- “(2,2,2-tri fluoro ethoxy) pyridin-2”-yl) methyl) sulfinyl)-1H-benzoimidazole -1-carbodithioate] was prepared. This free ligand was synthesized from the reaction of a (RS)-2-([3-methyl -4-(2,2,2-tri fluoroethoxy) pyridin-2-yl] methyl sulfinyl)-1H benzoimidazole, CS2 and NaOH in methanol as solvent. From reaction of dithiocarbamate salt (NaL) with metal ions (M); Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Pd(II)”, have obtained the DTC complexes at general molecular formula [M(L)2(H2O)2] and [Pd(L)2]. To characterize the ligand and its complexes, used different analyses methods such FTIR, UV-Vis, elemental microanalysis, atomic absoreption, magnetic susceptibil

... Show More
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
A new approach for the topical treatment of acne vulgaris by clindamycin HCL supported on kalion
...Show More Authors

Has been studied both processes Almetzaz and extortion of a substance Alklanda Maysan different amounts of Alcaúlan Guy 70% alcohol solution using the method when the wavelength

View Publication Preview PDF
Publication Date
Tue Apr 30 2024
Journal Name
Iraqi Journal Of Science
Synthesis, Characterization and Antimicrobial Evaluation for New Esters Derivatives Containing Two 1, 3, 4-Oxadiazole Units
...Show More Authors

     This work includes the synthesis of new ester compounds containing two 1,3,4-oxadiazole rings, 15a-c and 16a-c. This was done over seven steps, starting with p-acetamido-phenol 1 and 2-mercaptobenzoimidazole 2. The structure of the products was determined using FT-IR, 1H NMR, and mass spectroscopy. The evaluation of the antimicrobial activities of some prepared compounds was achieved against four types of bacteria (two types of gram-positive bacteria; Staphylococcus aureus and Bacillus subtilis, and two types of gram-negative bacteria, Pseudomonas aeruginosa and E. Coli), as well as against one types of fungus (C. albino). The results show moderate activit against the study bacteria, and the theoretical analysis of the toxi

... Show More
View Publication
Scopus (3)
Crossref (3)
Scopus Crossref
Publication Date
Mon Jun 20 2022
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
REVISION OF THE GENUS CHLAENIUS BONELLI, 1810 (COLEOPTERA, CARABIDAE), WITH A NEW RECORD SPECIES FROM IRAQ
...Show More Authors

In this paper, the species of the genus of Chlaenius Bonelli, 1810 (Coleoptera, Carabidae) were reviewed, and it was revealed that there are 21 confirmed species in Iraq; among them, the species of Chlaenius hamifer Chaudoir, 1856 was recorded for the first time in Iraq.
Diagnostic characters, a redescription of some of the morphological features, photographs and illustrations are provided for the new record species in this investigation.

View Publication Preview PDF
Scopus Crossref
Publication Date
Mon Jun 19 2017
Journal Name
Arabian Journal For Science And Engineering
A New Method to Tune a Fractional-Order PID Controller for a Twin Rotor Aerodynamic System
...Show More Authors

View Publication
Scopus (33)
Crossref (29)
Scopus Clarivate Crossref
Publication Date
Thu Feb 01 2024
Journal Name
Russian Journal Of Bioorganic Chemistry
Synthesis, Characterization, and Study of Anticancer Activities of New Schiff Bases and 1,3-Oxazepine Containing Drug
...Show More Authors

Objective: This study involved the synthesis of new Schiff bases and 1,3-oxazepine derivatives from the baclofen drug and study the anticancer activities. Methods: Baclofen was initially reacted with aromatic aldehydes to create Schiff base derivatives (Ia–Ib), which were then closed in the next step using anhydrous acids to form oxazepine derivatives (IIa–IId). Results: The title compounds were synthesized successfully and identified using FT-IR, 1H NMR, and 13C NMR spectroscopy. Additionally, compound (IIc)’s (3-(4-chloro-phenyl)-4-[2-(4nitro-phenyl)-4,7-dioxo-4,7-dihydro-[1,3] oxazepin-3-yl]butyric acid) anticancer activity was assessed using MTT assay against FTC-133 (thyroid cancer) compared with WRL-68 (normal cell line). Discus

... Show More
View Publication
Scopus (4)
Scopus Clarivate Crossref
Publication Date
Thu Jun 01 2023
Journal Name
Russian Journal Of Organic Chemistry
New Quinolin-2-one, Indazole, and Benzisoxazole Derivatives Derived from Chalcones: Synthesis, Characterization, and Biological Activity
...Show More Authors

View Publication
Scopus (5)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Tue Jun 20 2023
Journal Name
Baghdad Science Journal
Synthesis, Characterization and Antioxidant Activity of New Azo Ligand and Some Metal Complexes of Tryptamine Derivatives
...Show More Authors

 

Write a brief abstract about your paper’s subject of study. Write a brief abstract about your paper’s subject of study. Write a brief abstract about your paper’s subject of study. Write a brief abstract about your paper’s subject of study. Write a brief abstract about your paper’s subject of study. Write a brief abstract about your paper’s subject of study. Write a brief abstract about your paper’s subject of study. Write a brief abstract about your paper’s subject of study. Write a brief abstract about your paper’s subject of study. Write a brief abstract about your paper’s subject of study. Write a brief abstract about your paper’s subject of study. Write a brief abstract about your paper’s subject of

... Show More
View Publication Preview PDF
Scopus (11)
Crossref (2)
Scopus Crossref
Publication Date
Fri Mar 01 2013
Journal Name
Al-nahrain Journal Of Science
Synthetic and Characterization of Some new Schiff bases Complexes with CoII, NiII, CuII and PdII ions
...Show More Authors

A new ligand (H4L) and its complexes with (CoII, NiII, CuII and PdII). This ligand was prepared in two steps, in the first step a solution of terephthaldehyde in methanol reacted under refluxe with 1,2-phenylenediamine to give precursore compound which reacted in the second step with 2,4- dihydroxybenzaldehyde to give the ligand. The complexes were synthesized by direct reaction of the corresponding metal chloride with the ligand. The ligand and complexes were characterized by spectroscopic methods [FT-IR, UV-vis, 1HNMR, HPLC and atomic absorption], chloride contant in addition to conductivity measurement. The stability constant K and Gibbs free energy ∆G were calculated for [[Ni2(H2L)Cl2], [Cu2(H2L)Cl2] complexes using spectrophoto

... Show More
Publication Date
Wed Sep 30 2015
Journal Name
College Of Islamic Sciences
The impact of the organization of markets, old and new in the holy city of Karbala
...Show More Authors

Any city that has such a market and is organized, organized and established

Mini
And respect
Freedom of expression
Profile.
Conflict resolution and conflict resolution

Political
Which affected the growth of some markets
And religious th
The search for the return of economic and cultural activity and the emigration of some others
Cultural exchange and trade, which in turn
Al-Rifaie
We took the problem that we are experiencing
Menia, the holy city of Karbala in the market organization, has suffered from fierce attacks
Economic and heritage
e
As well as tourism and tourism, as it depends on the abundance of visitors, tourists and residents in terms of needs and motivation
Resource

... Show More
View Publication Preview PDF