This article presents a new cascaded extended state observer (CESO)-based sliding-mode control (SMC) for an underactuated flexible joint robot (FJR). The control of the FJR has many challenges, including coupling, underactuation, nonlinearity, uncertainties and external disturbances, and the noise amplification especially in the high-order systems. The proposed control integrates the CESO and SMC, in which the CESO estimates the states and disturbances, and the SMC provides the system robustness to the uncertainty and disturbance estimation errors. First, a dynamic model of the FJR is derived and converted from an underactuated form to a canonical form via the Olfati transformation and a flatness approach, which reduces the complexity of the controller design. Furthermore, by taking the advantage of available measurable states, the CESO is adopted to attenuate the noises and make SMC feasible for high-order systems. Moreover, the CESO estimates the disturbances, which relaxes the upper bound of the disturbance in the SMC and reduces the chattering due to smaller switching gains. A stability analysis of the closed-loop system is presented based on the Lyapunov method. The effectiveness of the proposed control is verified in simulations and experimentally on a real-time FJR system.
This research aims to examine the effectiveness of a teaching strategy based on the cognitive model of Daniel in the development of achievement and the motivation of learning the school mathematics among the third intermediate grade students in the light of their study of "Systems of Linear Equations”. The research was conducted in the first semester (1439/1440AH), at Saeed Ibn Almosaieb Intermediate School, in Arar, Saudi Arabia. A quasi-experimental design has been used. In addition, a (pre & post) achievement test (20 Questions) and a (pre & post) scale of learning motivation to the school mathematics (25 Items) have been applied on two groups: a control group (31Students), and an experimental group (29 Students). The resear
... Show MoreThe test considers from important methods and tools when we using the evaluation because it is a basic role in diagnosis & classification & motive & selection &guiding &prediction and the problem was formatted in some questions like ( what is physical variables that tall players needs n the game and effect on the game ? what is the tests that measures these variables also the defense rebound variable and is there a references standard specialized in that ?) , the aims of research represented by knowing to some physical abilities for tall players in basketball school and their tests and putting new tests to measure defense rebound to one player and tow tall players also limiting the standards degrees ( modified un following method ) to resul
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Language is one of God’s blessings to human beings through which he
distingushed them from other creatures, then how if this language was arabic.
God honored this language and in which he descended his Gracious Boole
that gave it glory and magnificance, and made it an immortal revelation to the
arab nation in their poetry, oration, history and human tendency to the life of
knowledge, mind leadershipe, innovation and progress.
This study aimed at evaluating the arabic language come program for
the new teachers. The sample was of (25) participants who were shown a
questionaire consisting of (60) items distributed on (9) fields. Then, the data
was processed statisically by using preauency rate, Kai s
In this article we study the variance estimator for the normal distribution when the mean is un known depend of the cumulative function between unbiased estimator and Bays estimator for the variance of normal distribution which is used include Double Stage Shrunken estimator to obtain higher efficiency for the variance estimator of normal distribution when the mean is unknown by using small volume equal volume of two sample .
The subject of youth care of important issues in view of what constitutes the importance
to the development of societies in general and as much as enjoy young people in any society
are good psychological health and agree psychosocial be healthy to be effective to invest their
energies and their potential for the progress of that society and development of the social
aspects and economic. The universities of the most important educational institutions that
provide care for young people, they are as well as providing information and expertise
necessary to prepare young people for life and the development of mental abilities, they are
different activities that will satisfy their needs physical, psychological, social and
The present work aims to study the efficiency of coagulation/ flocculation as 1st stage, natural gravity water filter or microfiltration (MF) as 2nd stage and nanofiltration (NF) technology as final stage for treatment of water of main outfall drain (MOD) for injection in Nasiriyah oil field. Effects of operating parameters such as coagulant dosage, speed and time of slow mixing step and settling time in the 1st stage were studied. Also feed turbidity and total suspended solids (TSS) in the 2
... Show MoreAbstract
The government spending in Iraq and witnessed the changes and developments, especially after 2003, which outweighed consumer spending at the expense of capital expenditure and increased support and diversity of trends towards improving pension conditions for member
... Show MoreLimestones have considerable commercial importance because they are used as building stones and are widely used for flooring and interior and exterior facings. On the other hand, the reserve calculation reveals the economic effectiveness of the investigation. This study aims to calculate the reserve of the middle Miocene limestone for engineering purposes. The limestone beds of the Nfayil Formation in Central Iraq have been studied over 15 outcrop sections. The Nfayil bed has an average thickness of about 1.64 m, while the overburden has an average of about 0.93 m. The average bulk density of limestone is 2.1 gm/cm3 . Kriging and triangulation method has been adopted and used in the calculation and assessment of reserve. The industrial laye
... Show MoreStatistical methods and statistical decisions making were used to arrange and analyze the primary data to get norms which are used with Geographic Information Systems (GIS) and spatial analysis programs to identify the animals production and poultry units in strategic nutrition channels, also the priorities of food insecurity through the local production and import when there is no capacity for production. The poultry production is one of the most important commodities that satisfy human body protein requirements, also the most important criteria to measure the development and prosperity of nations. The poultry fields of Babylon Governorate are located in Abi Ghareg and Al_Kifil centers according to many criteria or factors such as the popu
... Show MoreThis presented study is to make comparison of cross sections to produce 71As, 72As, 73As and 74As via different reactions with particle incident energy up to 60 MeV of alpha 100 MeV of proton as a part of systematic studies on particle-induced activations on enriched Ge, Ga, Rb and Nb targets and neutron capture. Theoretical calculation of production yield, and suggestion of optimum reaction to produce 71As, 72As, 73As and 74As, based on the main published and approved experimental results of excitation functions were calculated.