Preferred Language
Articles
/
2BfWSpABVTCNdQwCY4Xx
Performance Analysis of xPON Network for Different Queuing Models
...Show More Authors

Passive optical network (PON) is a point to multipoint, bidirectional, high rate optical network for data communication. Different standards of PONs are being implemented, first of all PON was ATM PON (APON) which evolved in Broadband PON (BPON). The two major types are Ethernet PON (EPON) and Gigabit passive optical network (GPON). PON with these different standards is called xPON. To have an efficient performance for the last two standards of PON, some important issues will considered. In our work we will integrate a network with different queuing models such M/M/1 and M/M/m model. After analyzing IPACT as a DBA scheme for this integrated network, we modulate cycle time, traffic load, throughput, utilization and overall delay mathematically for single OLT and multiOLT EPON system, and average delay and throughput for single OLT GPON system. A comparison of average delay and throughput between EPON and GPON is introduced with the same number of ONUs. The results show that the proposed multi-OLT EPON system can supports existing bandwidth allocation schemes with better performance than the single-OLT EPON. Cycle delay and average delay is decreased with multi-OLT system than in single OLT system, while throughput of multi-OLT system is higher than throughput of single OLT system. Splitting ratio and throughput in GPON is much higher than in EPON.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Mar 15 2019
Journal Name
Journal Of Baghdad College Of Dentistry
The effect of 2 different techniques in second stage implant surgery
...Show More Authors

Background: Dental implant is one of the most important options for teeth replacement. In two stage implant surgery, a few options could be used for uncovering implants, scalpel and laser are both considered as effective methods for this purpose. The Aim of the study: To compare soft tissue laser and scalpel for exposing implant in 2nd stage surgery in terms of the need for anesthesia, duration of procedure and pain level assessment at day 1 and day 7 post operatively using visual analogue scale . Materials and methods: Ten patients who received bilateral implants participated after healing period completed, gingival depth over each implant was recorded and then implant(s) were exposed by either scalpel or laser with determination for th

... Show More
View Publication
Scopus (2)
Crossref (4)
Scopus Crossref
Publication Date
Sun Mar 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
The Behavior of Scouring Around Multiple Bridge Piers Having Different Shapes
...Show More Authors
Abstract<p>In this research, a numerical simulation was conducted to study the behavior of the scouring pattern and the effect of spacing between bridge piers at specified hydraulic conditions such as velocity, depth of flow, and the sediment effective diameter. Moreover, the cross-section shape of piers and their effect on the scouring depth around bridge piers was studied, using Computational Fluid Dynamics (CFD), ANSYS (Fluent) software. A comparison of the simulation results obtained with previous laboratory investigations was done to verify the validity of the numerical model. Generally, the scour pattern using the CFD software gave good agreement with the experimental study. A reversed pro</p> ... Show More
View Publication
Scopus (13)
Crossref (7)
Scopus Crossref
Publication Date
Mon Dec 08 2025
Journal Name
Nanomaterials
High-Temperature Properties of Hot Mix Asphalt Modified with Different Nanomaterials
...Show More Authors

Rutting is a predominant distress in asphalt pavements, particularly in hot climatic regions. This study systematically investigated the high-temperature performance of hot mix asphalt modified with five nanomaterials, namely, nano-silica (NS), nano-alumina (NA), nano-titanium (NT), nano-zinc (NZ), and carbon nanotubes (CNTs), under consistent laboratory conditions. Modification dosages were selected up to 10% for NS, NA, and NT, and up to 5% for NZ and CNTs. The experimental methodology comprised the following: (i) binder rheological characterization through rotational viscosity, G*/sinδ, and multiple stress creep recovery (MSCR) to quantify rutting susceptibility; (ii) chemical and microstructural assessments using Fourier transf

... Show More
View Publication
Scopus (3)
Crossref (5)
Scopus Crossref
Publication Date
Thu Oct 01 2020
Journal Name
Journal Of Engineering
Load-settlement Behavior of Steel Piles in Different Sandy Soil Configurations
...Show More Authors

In the case where a shallow foundation does not satisfy with design requirements alone, the addition of a pile may be suitable to improve the performance of the foundation design. The lack of in-situ data and the complexity of the issues caused by lagging in the research area of pile foundations are notable. In this study, different types of piles were used under the same geometric conditions to determine the load-settlement relationships with various sandy soil relative densities. The ultimate pile capacity for each selected pile is obtained from a modified California Bearing Ratio (CBR) machine to be suitable for axial pile loading. Based on the results, the values of Qu for close-ended square pile were increased by 15

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Dec 30 2018
Journal Name
Journal Of Engineering
Synthesis and Characterization of Titanium Dioxide Nanoparticles under Different pH Conditions
...Show More Authors

Ethanol as a solvent, a precursor of titanium isopropoxide and a stabilizer of either hydrochloric acid or ammonium hydroxide was used to prepare a titanium dioxide aqueous solution. The aqueous solutions with different values of pH and the morphology of the resultant reaction of the nanoparticles of titanium dioxide were investigated. The X-ray diffraction showed that at low temperatures and with acidic solutions, rutile structures are more favorable to grow on titanium dioxide synthesized, while at low and average temperatures and with base solutions, anatase phase is more pronounced. The crystalline form and the re-confirmation of the crystallite size growth were observed by the scanning electron microscopy. The atomi

... Show More
View Publication Preview PDF
Crossref (6)
Crossref
Publication Date
Thu Sep 01 2022
Journal Name
Journal Of Engineering
Properties of Roller-Compacted Concrete Pavement Containing Different Waste Material Fillers
...Show More Authors

Waste materials might be utilized in various applications, such as sustainable roller compacted concrete pavements (RCCP), to lessen the negative environmental consequences of construction waste. The impacts of utilizing (brick, thermostone, granite, and ceramic) powders on the mechanical characteristics of RCCP are investigated in this study. To achieve this, the waste materials were crushed, grounded, and blended before being utilized as filler in the RCCP. After the mixes were prepared, compressive strength, splitting tensile strength, flexural strength, water absorption, density, and porosity were all determined. According to the research results, adding some of these powders, mainly brick and granite powder, enhances the mechanical

... Show More
View Publication Preview PDF
Scopus (10)
Crossref (5)
Scopus Crossref
Publication Date
Sun Dec 30 2018
Journal Name
Journal Of Engineering
Synthesis and Characterization of Titanium Dioxide Nanoparticles under Different pH Conditions
...Show More Authors

Ethanol as a solvent, a precursor of titanium isopropoxide and a stabilizer of either hydrochloric acid or ammonium hydroxide was used to prepare a titanium dioxide aqueous solution. The aqueous solutions with different values of pH and the morphology of the resultant reaction of the nanoparticles of titanium dioxide were investigated. The X-ray diffraction showed that at low temperatures and with acidic solutions, rutile structures are more favorable to grow on titanium dioxide synthesized, while at low and average temperatures and with base solutions, anatase phase is more pronounced. The crystalline form and the re-confirmation of the crystallite size growth were observed by the scanning electron microscopy. The atomic force micr

... Show More
Crossref (6)
Crossref
Publication Date
Mon Jun 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Using the Box Jenkins models to predict Iraq's cement production and to demonstrate its adequacy under future construction projects
...Show More Authors

تعد صناعة السمنت في العراق من اقدم الصناعات الحديثة واكثرها تطورا وتقدما ومن اقواها تاثيرا في الاقتصاد القومي. واذ توفر في صناعة السمنت العراقي كافة المستلزمات الناجحة من حيث توفر المواد الاولية والخبرات الفنية والتقنية واسواق ثابتة وراسخة محليا وعالميا فقد كان من المفروض ان يتم التوسع في هذه الصناعة، وان التخطيط لهذه الصناعة امرا ضروريا خاصة وان مادة السمنت هي احدى اهم المواد الرئيسة التي يؤثر توفره

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Jun 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Using ARIMA models to forecast the volume of cargo handled in Iraqi ports An applied study in the general company of Iraqi ports
...Show More Authors

Time series is an important statistical method adopted in the analysis of phenomena, practices, and events in all areas during specific time periods and predict future values ​​contribute to give a rough estimate of the status of the study, so the study aimed to adopt the ARIMA models to forecast the volume of cargo handled and achieved in four ports (Umm Qasr Port, Khor Al Zubair Port, Abu Flus Port, and Maqal Port(, Monthly data on the volume of cargo handled for the years (2006-2018) were collected (156) observations. The study found that the most efficient model is ARIMA (1,1,1).

The volume of go

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Fri May 15 2009
Journal Name
Journal Of Planner And Development
Preservation of heritage markets within an integrated framework to preserve the urban heritage in the historical centers of cities (selected models and experiments)
...Show More Authors

This research discusses the rehabilitation of heritage markets in the historical centers of Islamic Arab cities and their use in the field of cultural tourism as one of the most important tourist attractions and the subsequent revival of the national economy in addition to preserving the urban heritage as these markets part of the historical centers of cities. The research also discusses the preservation of the continuity of heritage markets as a product of cultural heritage value within an integrated framework to preserve the urban heritage in the historic centers of cities. The study then reviews a number of experiences of Arab and Islamic countries in the field of preserving and rehabilitating heritage markets, which qualify them to b

... Show More
View Publication Preview PDF