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
Thu Mar 09 2023
Journal Name
Coatings
Nondestructive Evaluation of Fiber-Reinforced Polymer Using Microwave Techniques: A Review
...Show More Authors

Carbon-fiber-reinforced polymer (CFRP) is widely acknowledged as a leading advanced material structure, offering superior properties compared to traditional materials, and has found diverse applications in several industrial sectors, such as that of automobiles, aircrafts, and power plants. However, the production of CFRP composites is prone to fabrication problems, leading to structural defects arising from cycling and aging processes. Identifying these defects at an early stage is crucial to prevent service issues that could result in catastrophic failures. Hence, routine inspection and maintenance are crucial to prevent system collapse. To achieve this objective, conventional nondestructive testing (NDT) methods are utilized to i

... Show More
View Publication
Scopus (12)
Crossref (11)
Scopus Clarivate Crossref
Publication Date
Fri Jan 01 2016
Journal Name
Iraqi J. Sci., Special Issue, Part B
Complex Dynamics in incoherent source with ac-coupled optoelectronic Feedback
...Show More Authors

The appearance of Mixed Mode Oscillations (MMOs) and chaotic spiking in a Light Emitting Diode (LED) with optoelectronic feedback theoretically and experimentally have been reported. The transition between periodic and chaotic mixed-mode states has been investigated by varying feedback strength. In incoherent semiconductor chaotically spiking attractors with optoelectronic feedback have been observed to be the result of canard phenomena in three-dimensional phase space (incomplete homoclinic scenarios).

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 (7)
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
Tue Dec 01 2020
Journal Name
Baghdad Science Journal
Designing a Microstrip Patch Antenna in Part of Ultra-Wideband Applications
...Show More Authors

In this work, a simulated study was carried out for designing a novel spiral rectangular patch of microstrip antenna that is used in ultra-wideband applications by using a high frequency structure simulator software (HFSS). A substrate with dielectric constant of 4.4 and height 2.10 mm (commercial substrate height available is about 0.8-1.575 mm) has been used for the design of the proposed antenna. The design basis for enhancing bandwidth in the frequency range 6.63 - 10.93 GHz is based on increasing the edge areas that positively affect the antenna's efficiency. This design makes the designed antenna cost less by reducing the area of the patch. It has been noticed that the bandwidth of the antenna under this study is increasing to 4.30

... Show More
View Publication Preview PDF
Scopus (3)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Fri Aug 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
(Measuring and analyzing the impact of financial crises on the main source for financing the public budget in Iraq) *
...Show More Authors

    Form recurrence of financial crises phenomenon disturbing and attention , and returns the reasons so that its negative effects were sharp and dangerous , because of the nature and cause of Ncaha , threatened political and economic stability of the countries in which they occur these crises , in addition to Machmlh these crises spread of contagion across multiple channels to include other countries many developed and developing , and the reason for this to the openness of the economic and financial witnessed by the countries affected by crises and other countries concerned, the financial crisis is a case of financial turmoil appears in one of the sections of the financial system one and extends to

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jul 01 2020
Journal Name
Plant Archives
Effect of sedimentation source on the nature occurrence and distribution of the feldspar in some soil of Alluvial plain Iraq
...Show More Authors

The current study was conducted to find out the effect of the sediment source (sedimentary of Iraqi-Iranian borderline and Tigris River) on the content and distribution of feldspar minerals and their effect on the optical properties of these minerals in some soils of Wasit and Maysan province. Eight pedons were chosen to represent the study area, five of them represented sediments coming from the borderline, which included pedons of (Badra, Taj Al-Din, Al-Shihabi, Jassan, and Galat), while two of them represent the sediments of the Tigris River (Essaouira, Al-Dabouni). Finally, the pedon of Ali Al-Gharbi represented the mixing area of sediments of all the torrents coming from borderline and the sediments of the Tigris River. The diagnostic

... Show More
Scopus (1)
Scopus
Publication Date
Tue Dec 13 2022
Journal Name
Lecture Notes In Networks And Systems
Design and FPGA Implementation of Matrix Multiplier Using DEMUX-RCA-Based Vedic Multiplier
...Show More Authors

View Publication
Scopus (2)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Wed Jun 01 2022
Journal Name
Baghdad Science Journal
Variable Selection Using aModified Gibbs Sampler Algorithm with Application on Rock Strength Dataset
...Show More Authors

Variable selection is an essential and necessary task in the statistical modeling field. Several studies have triedto develop and standardize the process of variable selection, but it isdifficultto do so. The first question a researcher needs to ask himself/herself what are the most significant variables that should be used to describe a given dataset’s response. In thispaper, a new method for variable selection using Gibbs sampler techniqueshas beendeveloped.First, the model is defined, and the posterior distributions for all the parameters are derived.The new variable selection methodis tested usingfour simulation datasets. The new approachiscompared with some existingtechniques: Ordinary Least Squared (OLS), Least Absolute Shrinkage

... Show More
View Publication Preview PDF
Scopus (6)
Crossref (3)
Scopus Clarivate 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 (15)
Crossref (8)
Scopus Crossref