Print ISSN: 1681-6900

Online ISSN: 2412-0758

Volume 37, 5A

Volume 37, 5A, May 2019, Page 148-187

Research Paper

Controlling the Q-Point in Distributed Feedback Lasers Using a Numerical Optimization Methodology

Hisham K. Hisham

Engineering and Technology Journal, 2019, Volume 37, Issue 5A, Pages 148-156
DOI: 10.30684/etj.37.5A.1

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.

Removal oil from produced water by using adsorption method with adsorbent a Papyrus reeds

Firas K. Al-Zuhairi; Rana Azeez; Suhair A. Mahdi; Wafaa A. Kadhim; Muna Kh. Al-Naamee

Engineering and Technology Journal, 2019, Volume 37, Issue 5A, Pages 157-165
DOI: 10.30684/etj.37.5A.2

A papyrus reed, as a type of unusable farming waste, was used as a
kind of low-cost biosorbent for the elimination a crude oil from produced water
that was produced in an Al-Ahdab field, Iraq, in a batch stirred operation
mode. Fourier transform infrared spectroscopy (FTIR) and scanning electron
microscope (SEM) were used to characterize the biosorbent before and after
adsorption. Batch tests were employed as a function of the contact time,
adsorbent dose, and the pH of the solution. The experimental results show at
increases the amount adsorbent dosage, pH and contact times, the removal
efficiencies were increases and optimum condition was obtained at pH value
equal to 9, 5000 ppm adsorbent dose and 45 minutes contact time for removal
about 94.5% of crude oil, for test sample initial crude oil concentration 257.06
ppm. Therefore it can be disposed of without environmental damage. The better
fitting for equilibrium sorption process data was satisfactorily by the
Freundlich isotherm model with (R2= 0.9665) and the adsorption kinetics best
described by a pseudo-second-order kinetic model.

Lung Cancer Detection from X-ray images by combined Backpropagation Neural Network and PCA

Israa S. Abed

Engineering and Technology Journal, 2019, Volume 37, Issue 5A, Pages 166-171
DOI: 10.30684/etj.37.5A.3

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.

A Group Authentication Protocol on Multilayer Structure for Privacy-Preserving IoT Environment

Maytham Azhar; Amin H. Seno

Engineering and Technology Journal, 2019, Volume 37, Issue 5A, Pages 172-180
DOI: 10.30684/etj.37.5A.4

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.

Optimization Using Taguchi Method for Physical and Mechanical Properties of Bio Mimicking Polymeric Matrix Composite for Orthodontic Application

Jenan S. Kashan

Engineering and Technology Journal, 2019, Volume 37, Issue 5A, Pages 181-187
DOI: 10.30684/etj.37.5A.5

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.