Abstract

Due to the continuing demand for larger bandwidth, the optical transport becoming general in the access network. Using optical fiber technologies, the communications infrastructure becomes powerful, providing very high speeds to transfer a high capacity of data. Existing telecommunications infrastructures is currently widely used Passive Optical Network that apply Wavelength Division Multiplexing (WDM) and is awaited to play an important role in the future Internet supporting a large diversity of services and next generation networks. This paper presents a design of WDM-PON network, the simulation and analysis of transmission parameters in the Optisystem 7.0 environment for bidirectional traffic. The sim

The work in this paper focuses on the system quality of direct and coherent communication system for two computers. A system quality is represented by Signal to Noise ratio (SNR) and Bit Error Rate (BER). First part of the work includes implementation of direct optical fiber communication system and measure the system quality .The second part of the work include implementation both the( homodyne and heterodyne)coherent optical fiber communication system and measure the system quality . Laser diode 1310 nm wavelength with its drive circuit used in the transmitter circuit . A single mode of 62.11 km optical fiber is selected as transmission medium . A PIN photo detector is used in the receiver circuit. The optical D-coupler was u

The current study was conducted on irrigational project called (Beat Zwena River), located in Jadedat- alshat, within the province of Dyala, which is divided from the right side of the Tigris River, the project significant environmental importance was passed in several agricultural areas estimated about 1600 acres, and it is also used for the purposes of irrigation and drinking. One of the major drawback for the current study is the almost lack data about the physiochemical parameter, in addition to measure (chlorophyll a and phyophtin of the River under investigation, in five locations for the period of October 2013 until June 2014. The range of studied properties was: 10.83 -38.75°C and 9.17 -28.5°C for air and water temperature,

Image retrieval is used in searching for images from images database. In this paper, content – based image retrieval (CBIR) using four feature extraction techniques has been achieved. The four techniques are colored histogram features technique, properties features technique, gray level co- occurrence matrix (GLCM) statistical features technique and hybrid technique. The features are extracted from the data base images and query (test) images in order to find the similarity measure. The similarity-based matching is very important in CBIR, so, three types of similarity measure are used, normalized Mahalanobis distance, Euclidean distance and Manhattan distance. A comparison between them has been implemented. From the results, it is conclud

In this work, polyvinylpyrrolidone (PVP), multi-walled carbon nanotubes (MWCNTs) nanocomposite was prepared and hybridized with Graphene (Gr) by the solution casting method.  The morphological and electrical properties were investigated by field effect scanning electron microscopy (FESEM) images, portraying a uniform dispersion of graphene within the PVP-MWCNT nanocomposite. The AC conductivity increased from (1.45552) to (2.34812) (Ω cm)^-1 with the use of nanocomposite. The increasing continues for the AC conductivity after hybridized with graphene up to (7.20641) (Ω cm)^-1. In addition, the performances of the prepared samples for gas sensor application have been investigated.

Background: Chronic obstructive pulmonary disease causes permanent morbidity, premature mortality and great burden to the healthcare system. Smoking is it's most common risk factor and Spirometry is for diagnosing COPD and monitoring its progression.

Objectives: Early detection of chronic obstructive pulmonary disease in symptomatic smokers’ ≥ 40years by spirometry.

Methods: A cross sectional study on all symptomatic smokers aged ≥ 40 years attending ten PHCCs in Baghdad Alkarkh and Alrisafa. Those whose FEV1/FVC was <70% on spirometry; after giving bronchodilator, were considered COPD +ve.

Results:  Overall, airway obstruction was seen in

The deployment of UAVs is one of the key challenges in UAV-based communications while using UAVs for IoT applications. In this article, a new scheme for energy efficient data collection with a deadline time for the Internet of things (IoT) using the Unmanned Aerial Vehicles (UAV) is presented. We provided a new data collection method, which was set to collect IoT node data by providing an efficient deployment and mobility of multiple UAV, used to collect data from ground internet of things devices in a given deadline time. In the proposed method, data collection was done with minimum energy consumption of IoTs as well as UAVs. In order to find an optimal solution to this problem, we will first provide a mixed integer linear programming m

Sub-threshold operation has received a lot of attention in limited performance applications.However, energy optimization of sub-threshold circuits should be performed with the concern of the performance limitation of such circuit. In this paper, a dual size design is proposed for energy minimization of sub-threshold CMOS circuits. The optimal downsizing factor is determined and assigned for some gates on the off-critical paths to minimize the energy at the maximum allowable performance. This assignment is performed using the proposed slack based genetic algorithm which is a heuristic-mixed evolutionary algorithm. Some gates are heuristically assigned to the original and the downsized design based on their slack time determined by static tim

A range of macrocyclic dinuclear metal (II) dithiocarbamate-based complexes are reported. The preparation of complexes was accomplished from either mixing of the prepared ligand with a metal ion or through a template one-pot reaction. The preparation of the bisamine precursor was achieved through several synthetic steps. The free ligand; potassium 2,2'-(biphenyl-4,4'-diylbis(azanediyl))bis(1-chloro-2-oxoethane-2,1diyl)bis(cyclohexylcarbamodithioate) (L) was yielded from the addition of CS2 to a bis-amine precursor in  KOH medium.A variety of analytical and physical methods were implemented to characterise ligand and its complexes. The analyses were based on spectroscopic techniques (FTIR, UV-Vis, mass spectroscopy and 1H, 13C-NMR sp

This study dealt with the reality of groundwater before Sulfur production in the Al-Mishraq field-1 and after production stopped in the field, by measuring the groundwater table for (44) wells in 2021, and comparing it to the groundwater table measured by the Polish company Centrozap in 1971, the groundwater table was a range between (187.71-205.8)m in 1971, but in 2021 it ranged was between (188.51-196.55)m.
Maps of the groundwater movement and water table were created using these data. It turned out that there was little change in the direction of groundwater flow; in both cases, the flow is from the west and northwest towards the east with a slight slope toward the southeast and the Tigris River. As for hydraulic properties, it w