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Hierarchical Stabilization and Tracking Control of a Flexible-Joint Bipedal Robot Based on Anti-Windup and Adaptive Approximation Control
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Bipedal robotic mechanisms are unstable due to the unilateral contact passive joint between the sole and the ground. Hierarchical control layers are crucial for creating walking patterns, stabilizing locomotion, and ensuring correct angular trajectories for bipedal joints due to the system’s various degrees of freedom. This work provides a hierarchical control scheme for a bipedal robot that focuses on balance (stabilization) and low-level tracking control while considering flexible joints. The stabilization control method uses the Newton–Euler formulation to establish a mathematical relationship between the zero-moment point (ZMP) and the center of mass (COM), resulting in highly nonlinear and coupled dynamic equations. Adaptive approximation-based feedback linearization control (so-called adaptive computed torque control) combined with an anti-windup compensator is designed to track the desired COM produced by the high-level command. Along the length of the support sole, the ZMP with physical restrictions serves as the control input signal. The viability of the suggested controller is established using Lyapunov’s theory. The low-level control tracks the intended joint movements for a bipedal mechanism with flexible joints. We use two control strategies: position-based adaptive approximation control and cascaded position-torque adaptive approximation control (cascaded PTAAC). The interesting point is that the cascaded PTAAC can be extended to deal with variable impedance robotic joints by using the required velocity concept, including the desired velocity and terms related to control errors such as position, force, torque, or impedance errors if needed. A 6-link bipedal robot is used in simulation and validation experiments to demonstrate the viability of the suggested control structure.

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Publication Date
Thu Nov 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
The Impact of Empowerment Human Strategy on Enhancing the Financial Performance: Empirical study on Working Banks in Jordan
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This study aimed at recognizing the impact of empowerment of human resources strategy on enhancing the financial performance in working banks in Jordan, the axes of the strategy were: informative sharing, free and independence, working teams, and organizational power. To achieve the objective of the study, a questionnaire is designed and distributed on the sample of the study, which represented 60 employees of Banks. After analyzing the data by using SPSS, the study resulted that there is positive impact of empowerment of human resources strategy on enhancing the financial performance in working banks in Jordan. It suggested that the working banks in Jordan should establish database, and to create working teams.

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Publication Date
Thu Oct 01 2015
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Biochemical studies on the effect of Crataegus aqueous extract on oxidative stress during ischemia/reperfusion induced myocardial injuries
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Background: myocardial ischemia-reperfusion (I/R) injury may occur in a variety of clinical settings and this remains a significant problem. Oxygen free radicals, produced on reperfusion have been shown to play a major role in myocardial I/R injury. Various therapeutic effects have been described for Crataegus. Additionally, it has been presented that Crataegus has protective effect against ischemia reperfusion induced myocardial injuries to various organs. Therefore, it seems possible that the administration of Crataegus might protect the heart against the ischemia reperfusion injury.
Objectives: I detected the chemical components and trace elements of the aqueous extract of Crataegus leaves and determine whether Crataegus extract pr

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Publication Date
Wed Jan 01 2014
Journal Name
Journal Of Mathematics Research
Effect of Some Geometric Transfers on Homology Groups
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Publication Date
Mon Oct 01 2018
Journal Name
Journal Of Pharmacy And Biological Sciences
Cytotoxic Effect of Methotrexate on Leishmania donovani Promastigotes
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Leishmania is auxotroph to folic acid,antifolates drug inhibit the synthesis and conversion of folate derivatives. In this study, cytotoxic effect of methotrexate was investigated on the procyclic promastigotes proliferation of L. donovani. The results showed a significant (p ≥ 0.05) difference in growth of treated groups at high concentrations (1000, 500, 250, 125.5) μM after 24, 48 hrs., while at 72 hrs. significant difference was observed at all concentration. The IC50 values was measurable after 24, 48 and 72 hrs. and it was 174.238, 52.283 and 109.175 μM, respectively. The present study showed the cytotoxic effect of methotrexate on the proliferation of promastigotes of the visceral type of Leishmania.

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Publication Date
Thu Jan 10 2019
Journal Name
Association Of Arab Universities Journal Of Engineering Sciences
Influence of Accelerated Curing on Fiber Reinforced Concrete
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The adopted accelerated curing methods in the experimental work are 55ºC and 82ºC according to British standard methods. The concrete mix with the characteristics compressive strength of 35MPa is design according to the ACI 211.1, the mix proportion is (1:2.65:3.82) for cement, fine and coarse aggregate, respectively. The concrete reinforced with different volume fraction (0.25, 0.5 and 0.75)% of glass, carbon and polypropylene fibers. The experimental results showed that the accelerated curing method using 82ºC gives a compressive strength higher than 55ºC method for all concrete mixes. In addition, the fiber reinforced concrete with 0.75% gives the maximum compressive strength, flexural and splitting tensile strength for all types of

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Publication Date
Sun Aug 03 2014
Journal Name
Journal Of Advances In Mathematics
On types of Delay in Delay Differential equation
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Publication Date
Thu Feb 01 2018
Journal Name
Iosr Journal Of Dental And Medical Sciences (iosr-jdms)
Inhibitory Effects of Nickel Chloride on Bone Composition
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Abstract: To study the effect of nickel chloride on bone composition of mice, a number of biophysical and biochemical parameters have been made use. The animals were divided into control and experimental and further subdivided into three groups I, II and III according to the dose of nickel chloride (NiCl2) administered to them i.e. 5.8, 12.8 and 28.2 mg/kg body weight, respectively. Femur bones were obtained by sacrificing the animals three weeks after weaning them once a week. The percentage loss between the wet weight and dry weight of femur in control animals was found to be 32.5+1.5 .In the three experimental groups I,II and III, the percentage loss was 30.4+1.4, 35.3+2.3 and 38.9+2.2 respectively. The percentage loss between the wet we

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Publication Date
Fri Dec 30 2022
Journal Name
مجلة نسق
Islamic Sharia’s position on the phenomenon of bullying
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The study was enriched by examining (Islamic Sharia’s position on the phenomenon of bullying) becausee bullying is a recurring aggressive behavior that Is one of the types of violence directed by a person or group of prsons; With the intent of deliberately harming and offending anotherr person or group of persons, It has several verbal, physical, electronIc or other formsforms Bullies may follow a policy of Ientimidation or intimidation, as well as ridicule; In order to belittle the victim .The study aims to know the Islamic Sharia ruling on bullying as a modern term for a content that Is as old as man, and the study reached several results, Including: Islam’s affirmation of the prohibition of this phenomenon In word, deed and gesture,

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Publication Date
Sun Apr 30 2023
Journal Name
Iraqi Journal Of Science
On The extension Bi-Normality of Linear Operators
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    In this paper, we introduce the bi-normality set, denoted by , which is an extension of the normality set, denoted by  for any operators  in the Banach algebra . Furthermore, we show some interesting properties and remarkable results. Finally, we prove that it is not invariant via some transpose linear operators.

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Publication Date
Mon Jul 01 2019
Journal Name
Journal Of Physics: Conference Series
Motivational efficacy of lasers on marrow haemopoetic cells
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Abstract<p>Lasers has been proved to increase tissue oxygenation, activate marrow progenitor cells, expanse the microcirculation, accelerate the restoration of functions, stimulate adaptation ability and stabilization of the hormonal status. The semisolid tissue present in the epiphysis of the bone where it’s structure is spongy or cancellous is bone marrow and it formed about 4% of body weight, the marrow is composed of hemopoietic cells, however, the structure of the marrow is of both cellular and non – cellular components. The hemopoietic stem cells are responsible of producing white blood cells, red corpuscles, platelets in addition to the fibroblasts, macrophages, adipocytes, osteoblast</p> ... Show More
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