Preferred Language
Articles
/
joe-835
Anti-Disturbance Compensator Design for Unmanned Aerial Vehicle
...Show More Authors

In this paper, an Anti-Disturbance Compensator is suggested for the stabilization of a 6-DoF quadrotor Unmanned Aerial vehicle (UAV) system, namely, the Improved Active Disturbance Rejection Control (IADRC). The proposed Control Scheme rejects the disturbances subjected to this system and eliminates the effect of the uncertainties that the quadrotor system exhibits. The complete nonlinear mathematical model of the 6-DoF quadrotor UAV system has been used to design the four ADRCs units for the attitude and altitude stabilization. Stability analysis has been demonstrated for the Linear Extended State Observer (LESO) of each IADRC unit and the overall closed-loop system using Hurwitz stability criterion. A minimization to a proposed multi-objective Output Performance Index (OPI) is achieved in the MATLAB environment to tune the IADRCs parameters using Genetic Algorithm (GA). The IADRC has been tested for the 6-DOF quadrotor under different tracking scenarios, including disturbance rejection and uncertainties elimination and compared with nonlinear and linear PID controllers. The simulations showed the excellent performance of the proposed compensator against the controllers used in the comparison.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Jun 01 2022
Journal Name
Political Sciences Journal
Political Transformations in The Republic of Turkmenistan During the Period (1991-2021)
...Show More Authors

After the fall of the Soviet Union, a number of Eastern Bloc countries and Soviet republics have witnessed political transition. However, Turkmenistan, as one of the former Soviet republics, succeeded to preserve the authoritarian nature of the former Soviet regime. This study seeks to answer a number of research questions, the most prominent of which are: How were the political elite in Turkmenistan able to preserve the legacy of the Soviet policy based on centralization of power and individual rule?. The study reaches a set of conclusions, the most important of which are:

1-The roots of the tyranny in Turkmenistan are du to internal and external structural factors. The most important of which are: the former Soviet policies of m

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Feb 01 2015
Journal Name
Journal Of Engineering
Effect of Saturation of Sandy Soil on the Displacement Amplitude of Soil Foundation System under Vibration
...Show More Authors

In this study, the response and behavior of machine foundations resting on dry and saturated sand was investigated experimentally. A physical model was manufactured to simulate steady state harmonic load at different operating frequencies. The effect of relative density, depth of embedment, foundation area as well as the imposed harmonic load was investigated. It was found that the amplitude of displacement of the foundation increases with increasing the amplitude of dynamic force and operating frequency meanwhile it decreases with increasing the relative density of sand, degree of saturation, depth of embedment and contact area of footing. The maximum displacement was noticed at 33.34 to 41.67 Hz. The maximum displaceme

... Show More
View Publication Preview PDF
Publication Date
Sun Feb 01 2015
Journal Name
Journal Of Engineering
Effect of Saturation of Sandy Soil on the Displacement Amplitude of Soil Foundation System under Vibration
...Show More Authors

In this study, the response and behavior of machine foundations resting on dry and saturated sand was investigated experimentally. A physical model was manufactured to simulate steady state harmonic load at different operating frequencies. The effect of relative density, depth of embedment, foundation area as well as the imposed harmonic load was investigated. It was found that the amplitude of displacement of the foundation increases with increasing the amplitude of dynamic force and operating frequency meanwhile it decreases with increasing the relative density of sand, degree of saturation, depth of embedment and contact area of footing. The maximum displacement was noticed at 33.34 to 41.67 Hz. The maximum displacement amplitude respons

... Show More
Preview PDF
Publication Date
Tue Feb 28 2017
Journal Name
Journal Of Engineering
Contributory Factors Related to Permanent Deformation of Hot Asphalt Mixtures
...Show More Authors

Permanent deformation (Rutting) of asphalt  pavements which appears in many roads in Iraq, have caused a major impact on pavement performance by reducing the useful service life of pavement and creating services hazards for highway users. The main objective of this research is investigating the effect of some contributory factors related to permanent deformation of asphalt concrete mixture. To meet the objectives of this research, available local materials are used including asphalt binder, aggregates, mineral filler and modified asphalt binder. The Superpave mix design system was adopted with varying volumetric compositions. The Superpave Gyratory Compactor was used to compact 24 asphalt concrete cylindrical specimens. To collect t

... Show More
View Publication Preview PDF
Publication Date
Wed Jul 31 2019
Journal Name
Journal Of Engineering
Asphaltene Precipitation Modeling of Sadi Formation in Halfaya Iraqi Oil Field
...Show More Authors

Asphaltene is a component class that may precipitate from petroleum as a highly viscous and sticky material that is likely to cause deposition problems in a reservoir, in production well, transportation, and in process plants. It is more important to locate the asphaltene precipitation conditions (precipitation pressure and temperature) before the occurring problem of asphaltene deposition to prevent it and eliminate the burden of high treatment costs of this problem if it happens. There are different models which are used in this flow assurance problem (asphaltene precipitation and deposition problem) and these models depend on experimental testing of asphaltene properties. In this study, the used model was equation of

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Thu Jun 09 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The financial aid of the Central Bank of Iraq to the government and its reflection on indicators of banking stability/ Applied Research
...Show More Authors

The research aims to define the images of financial aid that it provides within their tasks (central banks to governments) and how it can affect the indicators of banking stability, as well as monitoring the levels of banking stability in the Iraqi economy through the indicators used by the Central Bank of Iraq, and the importance of research in banking stability lies in Iraq, because any decrease in the movement of the aggregate banking stability index will reflect negatively on the financial sector in Iraq. Therefore, the Central Bank sought to provide financial aid to the government through a group of components, some of which are represented by initiatives that contribute to revitalizing the national economy and the other hel

... Show More
View Publication Preview PDF
Publication Date
Sun Dec 05 2010
Journal Name
Baghdad Science Journal
Stability of Nonlinear Systems of Fractional Order Differential Equations
...Show More Authors

In this paper, a sufficient condition for stability of a system of nonlinear multi-fractional order differential equations on a finite time interval with an illustrative example, has been presented to demonstrate our result. Also, an idea to extend our result on such system on an infinite time interval is suggested.

View Publication Preview PDF
Crossref
Publication Date
Wed Dec 15 2021
Journal Name
Journal Of Baghdad College Of Dentistry
The Effect of Recipient Jaw and Implant Dimensions on Pre- and Post- Loading Dental Implant Stability: A Prospective Clinical Study
...Show More Authors

Background: Implant stability is a mandatory factor for dental implant (DI) osseointegration and long-term success. The aim of this study was to evaluate the effect of implant length, diameter, and recipient jaw on the pre- and post-functional loading stability. Materials and methods: This study included 17 healthy patients with an age range of 24-61 years. Twenty-two DI were inserted into healed extraction sockets to replace missing tooth/ teeth in premolar and molar regions in upper and lower jaws. Implant stability was measured for each implant and was recorded as implant stability quotient (ISQ) immediately (ISQ0), and at 8 (ISQ8) and 12 (ISQ12) weeks postoperatively, as well as post-functional loading (ISQPFL). The pattern of implant

... Show More
View Publication Preview PDF
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Fri May 01 2020
Journal Name
Journal Of Engineering
Chemical and Thermal Investigation on Stability of Tanuma Formation Using Different Additives with Drilling Fluids
...Show More Authors

Wellbore stability is considered as one of the most challenges during drilling wells due to the
reactivity of shale with drilling fluids. During drilling wells in North Rumaila, Tanuma shale is
represented as one of the most abnormal formations. Sloughing, caving, and cementing problems
as a result of the drilling fluid interaction with the formation are considered as the most important
problem during drilling wells. In this study, an attempt to solve this problem was done, by
improving the shale stability by adding additives to the drilling fluid. Water-based mud (WBM)
and polymer mud were used with different additives. Three concentrations 0.5, 1, 5 and 10 wt. %
for five types of additives (CaCl2, NaCl, Na2S

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Nov 09 2015
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
The effect of different thermal treatments and pH on the stability of a glycyrrhizin which Product from the licorice plant, Glycyrrhiza glabra L: The effect of different thermal treatments and pH on the stability of a glycyrrhizin which Product from the licorice plant, Glycyrrhiza glabra L
...Show More Authors

The plant licorice is considered important plants as nutritionally and medically and economically, as a rich in phytochemical, vitamins and minerals, and being widely available, Research indicated the presence of many nutrients such as (proteins, Carbohydrates, vitamins and minerals) as well as presence of Glycyrrhizin which responsible of sweet taste, that allowing the possibility to use it as natural intensity sweetener with few calories in Sweetening of many food. This research is aimed to study the Stability of Glycyrrhizin toward the various manufacturing conditions such as (thermal treatment, pH of foods and microwaves), so three factorial experiments was implemented to find out the Stability as following: 100C° - 121C° - Microwa

... Show More
View Publication Preview PDF