Preferred Language
Articles
/
ijl-17
Design Considerations of Laser Source in a Ring Network Based on Fiber Distributed Data Interface (FDDI)
...Show More Authors

This work presents the use of laser diode in the fiber distributed data interface FDDI networks. FDDI uses optical fiber as a transmission media. This solves the problems resulted from the EMI, and noise. In addition it increases the security of transmission. A network with a ring topology consists of three computers was designed and implemented. The timed token protocol was used to achieve and control the process of communication over the ring. Nonreturn to zero inversion (NRZI) modulation was carried out as a part of the physical (PHY) sublayer. The optical system consists of a laser diode with wavelength of 820 nm and 2.5 mW maximum output power as a source, optical fiber as a channel, and positive intrinsic negative (PIN) photodiode with maximum responsivity at wavelength of 820 nm as a detector. Practical tests were carried out on the laser diode showed that the output characteristics and spectral characteristics of the laser diode depend largely on the drive current. The maximum separation distance between successive stations in the ring was 5.4 km. From the performance tests, it was concluded that the maximum throughput and maximum access delay are directly proportional to length of the transmitted information. A trade off between the transmitted information length and the maximum access delay is needed.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon May 11 2020
Journal Name
Baghdad Science Journal
A Cryptosystem for Database Security Based on TSFS Algorithm
...Show More Authors

Implementation of TSFS (Transposition, Substitution, Folding, and Shifting) algorithm as an encryption algorithm in database security had limitations in character set and the number of keys used. The proposed cryptosystem is based on making some enhancements on the phases of TSFS encryption algorithm by computing the determinant of the keys matrices which affects the implementation of the algorithm phases. These changes showed high security to the database against different types of security attacks by achieving both goals of confusion and diffusion.

View Publication Preview PDF
Scopus (7)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Fri Mar 31 2023
Journal Name
Journal Of Al-qadisiyah For Computer Science And Mathematics
A Cryptosystem for Database Security Based on RC4 Algorithm
...Show More Authors

Because of vulnerable threats and attacks against database during transmission from sender to receiver, which is one of the most global security concerns of network users, a lightweight cryptosystem using Rivest Cipher 4 (RC4) algorithm is proposed. This cryptosystem maintains data privacy by performing encryption of data in cipher form and transfers it over the network and again performing decryption to original data. Hens, ciphers represent encapsulating system for database tables

View Publication
Crossref (1)
Crossref
Publication Date
Wed Jan 01 2020
Journal Name
Ieee Access
A New Separable Moments Based on Tchebichef-Krawtchouk Polynomials
...Show More Authors

View Publication
Scopus (22)
Crossref (20)
Scopus Clarivate Crossref
Publication Date
Fri Dec 31 2010
Journal Name
International Journal Of Advancements In Computing Technology
A proposed Technique for Information Hiding Based on DCT
...Show More Authors

The aim of this work is to design an algorithm which combines between steganography andcryptography that can hide a text in an image in a way that prevents, as much as possible, anysuspicion of the hidden textThe proposed system depends upon preparing the image data for the next step (DCT Quantization)through steganographic process and using two levels of security: the RSA algorithm and the digitalsignature, then storing the image in a JPEG format. In this case, the secret message will be looked asplaintext with digital signature while the cover is a coloured image. Then, the results of the algorithmare submitted to many criteria in order to be evaluated that prove the sufficiency of the algorithm andits activity. Thus, the proposed algorit

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Wed Dec 01 2021
Journal Name
Bioresource Technology Reports
Biosynthesis of polyhydroxyalkanoate (PHA) by a newly isolated strain Bacillus tequilensis ARY86 using inexpensive carbon source
...Show More Authors

View Publication
Scopus (16)
Crossref (8)
Scopus Crossref
Publication Date
Wed Jun 11 2003
Journal Name
Iraqi Journal Of Laser
Microdrop Size Measurement in a Mixing Unit Using Laser Technique
...Show More Authors

One of the troublesome duties in chemical industrial units is determining the instantaneous drop size distribution, which is created between two immiscible liquids within such units. In this work a complete system for measuring instantaneous droplet size is constructed. It consists of laser detection system (1mW He-Ne laser), drop generation system (turbine mixer unit), and microphotography system. Two immiscible liquids, water and kerosene were mixed together with different low volume fractions (0.0025, 0.02) of kerosene (as a dispersed phase) in water (as a continuous phase). The experiments were carried out at different rotational speed (1180- 2090 r.p.m) of the turbine mixer. The Sauter mean diameter of the drops was determined by la

... Show More
View Publication Preview PDF
Publication Date
Sun Aug 01 2021
Journal Name
Journal Of Engineering
Utilization of Iraqi Metakaolin in Special Types of Concrete: A Review Based on National Researches
...Show More Authors

Portland cement concrete is the most commonly used construction material in the world for decades. However, the searches in concrete technology are remaining growing to meet particular properties related to its strength, durability, and sustainability issue. Thus, several types of concrete have been developed to enhance concrete performance. Most of the modern concrete types have to contain supplementary cementitious materials (SCMs) as a partial replacement of cement. These materials are either by-products of waste such as fly ash, slag, rice husk ash, and silica fume or from a geological resource like natural pozzolans and metakaolin (MK). Ideally, the utilization of SCMs will enhance the concrete performance, minimize

... Show More
View Publication Preview PDF
Crossref (8)
Crossref
Publication Date
Mon Jun 01 2020
Journal Name
Iraqi Journal Of Physics
Prospect of CW Raman Laser in Silicon- on- Insulator Nano-Waveguides
...Show More Authors
 
Numerical analysis predicts that continuous-wave (CW) Raman lasing is possible in Silicon-On-insulator (SOI) nano-waveguides, despite of presence of free carrier absorption. The scope of this paper lies on lasers for communication systems around 1550 nm wavelength. Two types of waveguide structures Strip and Rib waveguides have been incorporated. The waveguide structures have designed to be 220 nm in height. Three different widths of (350, 450, 1000) nm were studied. The dependence of lasing of the SOI Raman laser on effective carrier lifetime was discussed, produced by tow photon absorption. At telecommunication wavelength of 1550 nm, Raman lasing threshold was calculated to be 1.7 mW in Rib SOI waveguide with dimen
... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Tue Aug 15 2023
Journal Name
Journal Of Economics And Administrative Sciences
Industries Based on the Petrochemical Industry in Iraq-Plastics Industry as a Model
...Show More Authors

This study came to discuss the subject of industries dependent on petrochemical industries in Iraq (plastic as a model) during the period 2005–2020, and the study concluded that the plastic industries contribute to areas of advancement and progress and opportunities to deal efficiently with the challenges posed by the new variables, the most important of which is the information revolution. communications and trade liberalization, and this is what contributes to the competitiveness of these industries. And because the petrochemical industry in Iraq has an active role in establishing plastic industrial clusters and clusters of micro, small, and medium industries by providing the necessary feedstock for these industries in various fields

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Mon Jul 10 2023
Journal Name
Russian Journal Of Bioorganic Chemistry
Synthesis and Characterization of New 1,3,4-Oxadiazole Ring on Creatinine Derivatives Using Iodine and Study Their Anticancer Effect
...Show More Authors

View Publication
Scopus (3)
Crossref (2)
Scopus Clarivate Crossref