2024-03-29T10:06:40Z
https://etj.uotechnology.edu.iq/?_action=export&rf=summon&issue=13421
Engineering and Technology Journal
ETJ
1681-6900
1681-6900
2019
37
5A
Controlling the Q-Point in Distributed Feedback Lasers Using a Numerical Optimization Methodology
Hisham
Hisham
In this paper, a new methodology for controlling the Q-point in the distributed feedback (DFB) lasers is proposed. The method based on reducing the DFB transient period (TP) by optimizing laser’s model parameters numerically. The analysis has taken into account investigated the effects of the laser injection current (Iinj), the dc-bias level (Ibias), the temperature (T) variation, and the gain compression factor (ε). Results showed that by optimizing the value of Iinj, Ibias, T and ε; the Q-point could be controlled effectively. Where increasing the current ratio (i.e., Iinj/Ith) leads to reduce the TP value. In addition, by increasing Iinj and/or Ibias, the relaxation oscillation period (TRO) and the laser delay time (TDelay) are reduced significantly. From the other hand, the temperature varying may push the DFB laser to operate in an improper region through increasing the TP value; which may lead it to operate in the off-mode. Moreover, as ε is increased, the sinusoidal oscillations are dramatically damped results in a reduction in the TRO value and larger period of stabilized.
Critical system
Distributed feedback (DFB) lasers
dynamic characteristics
Equilibrium (Q-point) point
semiconductor diode lasers (SDLs) transient response
2019
05
25
148
156
https://etj.uotechnology.edu.iq/article_168780_1bceecb9b4444db8ddc168fa179c8a76.pdf
Engineering and Technology Journal
ETJ
1681-6900
1681-6900
2019
37
5A
Removal oil from produced water by using adsorption method with adsorbent a Papyrus reeds
Firas
Al-Zuhairi
Rana
Azeez
Suhair
Mahdi
Wafaa
Kadhim
Muna
Al-Naamee
A papyrus reed, as a type of unusable farming waste, was used as akind of low-cost biosorbent for the elimination a crude oil from produced waterthat was produced in an Al-Ahdab field, Iraq, in a batch stirred operationmode. Fourier transform infrared spectroscopy (FTIR) and scanning electronmicroscope (SEM) were used to characterize the biosorbent before and afteradsorption. Batch tests were employed as a function of the contact time,adsorbent dose, and the pH of the solution. The experimental results show atincreases the amount adsorbent dosage, pH and contact times, the removalefficiencies were increases and optimum condition was obtained at pH valueequal to 9, 5000 ppm adsorbent dose and 45 minutes contact time for removalabout 94.5% of crude oil, for test sample initial crude oil concentration 257.06ppm. Therefore it can be disposed of without environmental damage. The betterfitting for equilibrium sorption process data was satisfactorily by theFreundlich isotherm model with (R2= 0.9665) and the adsorption kinetics bestdescribed by a pseudo-second-order kinetic model.
2019
05
25
157
165
https://etj.uotechnology.edu.iq/article_168781_6ce7966cc287a557c75f237a8b0be995.pdf
Engineering and Technology Journal
ETJ
1681-6900
1681-6900
2019
37
5A
Lung Cancer Detection from X-ray images by combined Backpropagation Neural Network and PCA
Israa
Abed
The lungs are portion of a complex unit, enlarging and relaxing numerus times every day to supply oxygen and exude CO2. Lung disease might occur from troubles in any part of it. Carcinoma often called Cancer is the generally rising and it is the most harmful disease happened in humankind. Carcinoma occurs because of uncontrolled growth of malignant cells inside the tissues of the lungs. Earlier diagnosis of cancer can help save large numbers of lives, while any delay or fail in detection may cause additional serious problems leading to sudden fatal death. The objective of this study is to design an automated system with an ability to improve the detection process in order to perform advanced recognition of the disease. The diagnosis techniques include: X-rays, MRI, CT images etc. X-ray is the common and low-cost technique that is widely used and it is relatively available for everyone. Rather than new techniques like CT and MRI, X-ray is human dependable, meaning it needs a Doctor and X-ray specialist in order to determine lung cases, so developing a system which can enhance and aid in diagnosis, can help specialist to determine cases in easily.
Lung Cancer
Intelligent Systems
Classification
feature extraction
Pattern Recognition
2019
05
01
166
171
https://etj.uotechnology.edu.iq/article_168782_60724506d4d6341c8a7cbeb462e3bc72.pdf
Engineering and Technology Journal
ETJ
1681-6900
1681-6900
2019
37
5A
A Group Authentication Protocol on Multilayer Structure for Privacy-Preserving IoT Environment
Maytham
Azhar
Amin
Seno
In the Internet of Things (IoT) systems, large amounts of data are accumulated from anywhere at any time, which may attack individuals' privacy, especially when systems are utilized in medical and everyday environments. With the promise of IoT's proactive systems, the integration of smart things into standard Internet creates several security challenges, because most Internet technologies, communication protocols and sensors are not designed to support IoT. Recent research studies have shown that launching security / privacy attacks against IoT active systems, in particular, Wearable Medical Sensor (WMS) systems, may lead to catastrophic situations and life-threatening conditions. Therefore, security threats and privacy concerns in the IoT area should be actively studied. This causes us in this paper to create a privacy authentication protocol for IoT end-devices on a four-layer structure that does not have the ability to accurately identify the device of request's sender so that some attacks can be minimized. We used the Blakley Sharing scheme to design a key generation and distribution system for secure communications between edge devices and end devices and examined the security properties of the protocol for the five common attacks in the IoT. The results of the experiments show that the proposed authentication protocol by the Blakley method is more efficient with increasing number of instructions in both fog structures and in a without fog structure, which shows a higher flexibility of the Blakley method than the Schemer because of the increasing number of instructions indicating increasing the number of nodes in the network.
Internetof Things
(IoT)
security
privacy
authentication
Blak ley Sharing scheme
2019
05
01
172
180
https://etj.uotechnology.edu.iq/article_168783_9d3cbb45e37464e828aab21a93a8e737.pdf
Engineering and Technology Journal
ETJ
1681-6900
1681-6900
2019
37
5A
Optimization Using Taguchi Method for Physical and Mechanical Properties of Bio Mimicking Polymeric Matrix Composite for Orthodontic Application
Jenan
Kashan
This work take in consideration the application of Taguchi optimization methodology in optimizing the parameters for processing (composition, compounding pressure) and their effects on the output physical (Density and true porosity) properties and mechanical(fracture strength and microhardness) properties for the Nano HA,Al2O3 fillers reinforced HDPE hybrid composite material for orthodontic application. An orthogonal array of the Taguchi approach was used to analyses the effect of the processing parameters on the physical and mechanical properties. On the other hand, the surface roughness and particle size distribution were also calculated to study their effect on the output properties. The result shows that the Taguchi approach can determine the best combination of processing parameters that can provide the optimal physical and mechanical conditions, which are the optimum values (the optimum composition was15HA/ 5Al2O3/80HDPE, and optimum compounding pressure was102 MPa.
Taguchi method
physical Properties
hybrid biocomposite
Mechanical properties
2019
05
01
181
187
https://etj.uotechnology.edu.iq/article_168784_042ac17e4e615832ae9831abadc260a8.pdf