Preferred Language
Articles
/
3BaeR4cBVTCNdQwCwkBF
Adaptive Approximation Control of Robotic Manipulators: Centralized and Decentralized Control Algorithms
...Show More Authors

The regressor-based adaptive control is useful for controlling robotic systems with uncertain parameters but with known structure of robot dynamics. Unmodeled dynamics could lead to instability problems unless modification of control law is used. In addition, exact calculation of regressor for robots with more than 6 degrees of freedom is hard to be calculated, and the task could be more complex for robots. Whereas the adaptive approximation control is a powerful tool for controlling robotic systems with unmodeled dynamics. The local (partitioned) approximation-based adaptive control includes representation of the uncertain matrices and vectors in the robot model as finite combinations of basis functions. Update laws for the weighting matrices are obtained by the Lyapunov-like design. Therefore, this work is focused function approximation-based control algorithms considering centralized and decentralized approaches. In this work, the following control algorithms are designed: (1) Adaptive hybrid regressor-approximation control. This work attempts to combine the features of both the regressor and the approximation techniques in adaptive control. The regressor technique is a powerful tool for adaptive control of the known structure of modeling while the approximation is useful for estimation of time-varying uncertainty. Therefore, this work proposes adaptive hybrid regressor and approximation control for robots in both free and constrained spaces. The control law consists of three terms: (i) regressor term for initial estimation of the known structure of the robot dynamics, e.g. inertia matrix, Coriolis and centripetal matrix and gravity vector, and (ii) approximation term for estimation of internal and external disturbances resulted from the inexact calculation of regressor matrix and unknown modeling of friction, etc, and (iii) robust term consists of switching sgn(.) function. The control law is designed based on updating the uncertain parameters and the weighting coefficients corresponding to regressor and approximation respectively with position/force tracking purposes. The proposed controller is stable in the sense of Lyapunov stability. (2) Decentralized adaptive partitioned approximation control. Partitioned approximation control is avoided in most decentralized control algorithms; however, it is essential to design feedforward control with improved tracking accuracy. As a result, this work is focused on decentralized adaptive partitioned approximation control for complex robotic systems using the orthogonal basis functions as strong approximators. In essence, the partitioned approximation technique is intrinsically decentralized with some modifications. The proposed decentralized control law consists of three terms: the partitioned approximation-based feedforward term that is necessary for precise tracking, the high gain-based feedback term, and the adaptive sliding gain-based term for compensation of modeling error. The passivity property is essential to prove the stability of local stability of the individual subsystem with guaranteed global stability. Simulation experiments on 2-link robot and 6-link biped robot are performed to prove the effectiveness of the proposed algorithms.

View Publication
Publication Date
Wed Mar 03 2021
Journal Name
Innovative Infrastructure Solutions
Experimental investigation of a new sustainable approach for recycling waste styrofoam food containers in lightweight concrete
...Show More Authors

View Publication
Scopus (9)
Crossref (5)
Scopus Clarivate Crossref
Publication Date
Thu Dec 30 2021
Journal Name
College Of Islamic Sciences
Title of Thesis The creedal purposes deduced from the Almighty’s saying: {It is easy for me}
...Show More Authors

 Summary

    I wanted to address this topic because of creedal purposes importance,and its r le in regulating lives of individuals and society, and to talk about purposes of Almighty's saying:{It is easy for me},to simplify its meanings for general educated person to obtain the believe of the Creator’s power and his oneness.

Therefore,this research came,whichincludes:an introduction and topics, first :concept of creedal objectives and their divisions,second: creedal purposes in Almighty’s saying:{It is easy for me},and conclusion:in where most important results were included:

... Show More
View Publication Preview PDF
Publication Date
Wed Dec 11 2019
Journal Name
Journal Of The College Of Education For Women
Investigating Difficulties Faced by Iraqi EFL Learners in Identifying the Illocutionary Force of the Reduplicative Words
...Show More Authors

A reduplicative word is an important phenomenon in all language studies because it reflects many functions in language communication such as plurality, emphasis, contrast, imitation.  The various instances of reduplicative words in a particular language reflect the richness and uniqueness of that language. Moreover, such variation gives insights into both culture and thought. A reduplicative word is a linguistic phenomenon found in the syntactic, morphological, phonological and semantic levels. The current study aims at investigating the illocutionary force of English reduplicative words in some selected English colloquial utterances. To achieve this aim, an analytical -pragmatic approach has been used by adopting Searle’s (1979)

... Show More
View Publication Preview PDF
Publication Date
Sun Jan 01 2023
Journal Name
Bionatura
Detection of lukf-pv gene in Staphylococcus aureus isolated from pregnant women with Urinary tract infection
...Show More Authors

Scopus Crossref
Publication Date
Sat Jan 02 2021
Journal Name
Journal Of The College Of Languages (jcl)
The problems of Google Translate: Los servicios de la traducción automática de Google y sus problemas
...Show More Authors

There are numbers of automatic translation services that internet users can choose to automatically translate a certain text, and Google translate is one of these automatic services that proposes over 51 Languages. The present paper sheds light on the nature of the translation process offered by Google, and analyze the most prominent problems faced when Google translate is used. Direct translation is common with Google Translate and often results in nonsensical literal translations, particularly with long compound sentences. This is due to the fact that Google translation system uses a method based on language pair frequency that does not take into account grammatical rules which, in turn, affects the quality of the translation. The

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The Impact of Public Spending on Kaldor's Square Variables in Iraq for the period (2005-2016).
...Show More Authors

The paper aims to measure and analysis the impact Public Spending on Iraq economy (Kaldor Variables).

 (variables of the magic square Kaldor) and them in after 2003.

The paper adopted econometric Methods to test the stationarity of the Variables under consideration. For the period (2005-2016) by using multiple regression and estimation the Impulse response function (IRF), by adopting Eviews 10 program.

The results of Impulse response function for the following five-years after the period under consideration reflexes that public expenditure (PEX) was fluctuating between positive and negative in all the variables of the research and this shows the fragility of the performance of fiscal policy in Iraq.

T

... Show More
View Publication Preview PDF
Publication Date
Sun Mar 04 2012
Journal Name
Baghdad Science Journal
Using fuzzy logic for estimating monthly pan evaporation from meteorological data in Emara/ South of Iraq
...Show More Authors

Evaporation is one of the major components of the hydrological cycle in the nature, thus its accurate estimation is so important in the planning and management of the irrigation practices and to assess water availability and requirements. The aim of this study is to investigate the ability of fuzzy inference system for estimating monthly pan evaporation form meteorological data. The study has been carried out depending on 261 monthly measurements of each of temperature (T), relative humidity (RH), and wind speed (W) which have been available in Emara meteorological station, southern Iraq. Three different fuzzy models comprising various combinations of monthly climatic variables (temperature, wind speed, and relative humidity) were developed

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Dec 20 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Proposal guide for abilities building in SAIs: Applied research in the Federal Board of Supreme Audit
...Show More Authors

SAIs has a pivotal role in enhancing public sector performance through its quest to achieve the greatest possible efficiency and effectiveness in its, so  it has to adopt applied framework for abilities building, the research aims to shed light on the role of SAIs and the nature of their  work,  and  the definition for its abilities building, and to prepare a proposal for abilities building applied to work with the SAI in the Republic of Iraq (of the Federal Board of Supreme Audit ),the Researchers reached conclusions, namely: abilities building is the outcome of the interaction between the reality of all of the employees of the SAI and the institution itself and the environment and the specific requirements of the de

... Show More
View Publication Preview PDF
Publication Date
Mon Sep 30 2024
Journal Name
Iraqi Journal Of Science
Overlapping Structure Detection in Protein-Protein Interaction Networks Using a Modified Version of Particle Swarm Optimization
...Show More Authors

In today's world, the science of bioinformatics is developing rapidly, especially with regard to the analysis and study of biological networks. Scientists have used various nature-inspired algorithms to find protein complexes in protein-protein interaction (PPI) networks. These networks help scientists guess the molecular function of unknown proteins and show how cells work regularly. It is very common in PPI networks for a protein to participate in multiple functions and belong to many complexes, and as a result, complexes may overlap in the PPI networks. However, developing an efficient and reliable method to address the problem of detecting overlapping protein complexes remains a challenge since it is considered a complex and har

... Show More
View Publication
Scopus Crossref
Publication Date
Wed Nov 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Nonparametric statistical study for the crime motives on a sample of inmates in Khartoum State prisons
...Show More Authors

The aim of the research was to investigate the use of non-parametric tests in the analysis of the questionnaire and how to choose the appropriate test for testing the hypothesis of the study of crime motives in Khartoum State. The data were collected through the primary sources by designing a questionnaire and distributed to a sample of inmates in Khartoum state; the data were analysis by SPSS program using the analytical statistical method through using some of the suitable non-parametric tests for each case. The most important results of the research were: there was significant relationship between the type of crime and the age group therefore, we found that the age group (20-29) was the most frequent crime particularly, the fi

... Show More
View Publication Preview PDF
Crossref