Preferred Language
Articles
/
alkej-156
Aircraft Lateral-Directional Stability in Critical Cases via Lyapunov Exponent Criterion

Based on Lyapunov exponent criterion, the aircraft lateral-directional stability during critical flight cases is presented. A periodic motion or limit cycle oscillation isdisplayed. A candidate mechanism for the wing rock limit cycle is the inertia coupling between an unstable lateral-directional (Dutch roll) mode with stable longitudinal (short period) mode. The coupling mechanism is provided by the nonlinear interaction of motion related terms in the complete set equations of motion. To analyze the state variables of the system, the complete set of nonlinear equations of motion at different high angles of attack are solved. A novel analysis including the variation of roll angle as a function of angle of attack is proposed. Furthermore the variation of Lyapunov exponent parameter as function of time is introduced. The numerical result indicated that the system became lightly damped at high angle of attack with increasing the amplitude of aircraft state variables limit cycle. A good agreement between the numerical result and published work is obtained for the onset of limit cycle oscillation, almost at .

View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Feb 28 2023
Journal Name
Iraqi Journal Of Science
The Digital Change Detection for Low Resolution Satellite Images in Weathering Estimation

      The detection and estimation of weathering conditions have become a very important daily necessity in our life. For this purpose, several satellites of low resolution imagery were launched by the weathering and environmental agencies. The important weather paremeters are temperuter, wind direction,  velocity, clould and humidity, etc. The low resolution images often deal with large-scale phenomena and the interpretation and projection of the produced data requires continuous development of tools and criteria.              In this paper, the low spatial resolution data generated by the moderate resolution imaging spectroradiometer (MODIS) were used to monitor the cloud density and direction above Iraq and i

... Show More
Scopus Crossref
View Publication Preview PDF
Publication Date
Fri Mar 31 2023
Journal Name
Wasit Journal Of Computer And Mathematics Science
Security In Wireless Sensor Networks Based On Lightweight Algorithms : An Effective Survey

At the level of both individuals and companies, Wireless Sensor Networks (WSNs) get a wide range of applications and uses. Sensors are used in a wide range of industries, including agriculture, transportation, health, and many more. Many technologies, such as wireless communication protocols, the Internet of Things, cloud computing, mobile computing, and other emerging technologies, are connected to the usage of sensors. In many circumstances, this contact necessitates the transmission of crucial data, necessitating the need to protect that data from potential threats. However, as the WSN components often have constrained computation and power capabilities, protecting the communication in WSNs comes at a significant performance pena

... Show More
Crossref
View Publication
Publication Date
Thu Sep 15 2022
Journal Name
Alustath Journal For Human And Social Sciences
Coming of Age in Times of Epidemics: Laurie Halse Anderson’s ‎Fever 1793‎

The frenzy caused by the horrific news on the TVs and the social media about COVID19 brings to the forefront the catastrophic epidemics in the past that led to mass deaths and haunt the imagination of historians and public alike. Works of fiction often depict the disastrous consequences of these epidemics, both real and imagined, focusing on the gothic experience the characters endure and their struggle to survive the disasters. This article explores this major issue in a contemporary novel, Laurie Halse Anderson’s Fever 1793 (2000). It chronicles the journey of the female protagonist and her struggle to survive and achieve autonomy during the historical yellow fever that hit Philadelphia more than two centuries ago, which stuck to the me

... Show More
Crossref (1)
Crossref
Publication Date
Sat Aug 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Simulation of Sediment Transport in the Upper Reach of Al-Gharraf River
Abstract<p>For the past few years, the sediment began to accumulate in Al-Gharraf River which reduces the flow capacity of the River. In the present research, a numerical model was developed using Hec-Ras software, version 5.0.4. to simulate the flow and sediment transport in the upper reach of the river. The hydrological and cross-section data measured by the Ministry of Water Resources, for the reach located between Kut and Hai cities and having a length of 58200 m, was used to perform calibration and verification of the model. Moreover, field sampling of suspended and bed loads was gathered for five months starting from 7/2/2019, and laboratory tests of samples were conducted to be used as in</p> ... Show More
Scopus (5)
Crossref (1)
Scopus Crossref
View Publication
Publication Date
Sun May 15 2022
Journal Name
Bionatura
Comparative anatomical study to skeleton for same species of Turtles in Iraq

Bones were recorded in the skeleton of some species of Iraqi turtle Mauremys rivulata; the objectives of this study came in light of current conditions, environmental developments, talents and techniques of biological studies taking place in the country, need for an anatomy guide in river turtles of Iraqi species, to identify all kinds of similarities and differences with their preaching, this work or study has become written in response to those modern needs. It is designed to be one of the resources for those interested in biological studies, beginners or professionals, and veterinarians, distinguishing them from marine and global species. Turtles were dissected in the laboratories of the Research Center and Museum of Natural Hist

... Show More
Scopus Crossref
View Publication
Publication Date
Wed Mar 04 2015
Journal Name
Environmental Earth Sciences
Scopus (32)
Crossref (22)
Scopus Clarivate Crossref
View Publication
Publication Date
Wed Mar 16 2016
Journal Name
World Journal Of Pharmaceutical Research
Publication Date
Mon Apr 04 2016
Journal Name
Journal Of Entomology And Zoology Studies
Publication Date
Wed Apr 02 2014
Journal Name
Iraqi Journal Of Physics
The evaluation of left ventricle stiffness index in patients suffering from hypertension

Many diseases can produce cardiac overload, of these disease hypertension, valve disease congenital anomaly in addition to many other disease. One of the most common diseases causing left ventricle overload is hypertension. A long term hypertension can cause myocardium hypertrophy leading to changes in the cardiac contractility and reduced efficiency. The investigations were carried out using conventional echocardiography techniques in addition to the tissue Doppler imaging (TDI) from which many noninvasive measurements can be readily obtained. The study has involved the effect of hypertension on the myocardium stiffness index through the measurement of early diastolic filling (E) and the early velocity of lateral mitral annulus (E

... Show More
Publication Date
Tue Aug 15 2023
Journal Name
Alustath Journal For Human And Social Sciences
Autoimmunity and the Terroristic Schemes in Dan Brown's The Da Vinci Code

From a medical perspective, autoimmunity reflects the abnormal behaviour of a human being. This state is shaped when the defense of an organism betrays its own tissues. Allegedly, the immune system should protect the body against attacking cells. When an autoimmune disease attacks, it results in perilous actions like self-destruction. However, from a psychological perspective, the French philosopher Jacques Derrida (1930-2004) explains that autoimmunity harms both the self and the other. As a result, the organ disarms the betraying cells, as the immune system cannot provide necessary protection. From a literary perspective, Derrida has termed autoimmunity as deconstruction for almost forty years. Autoimmunity starts with the stage of a norm

... Show More
View Publication Preview PDF