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Practically Robust Fixed-Time Convergent Sliding Mode Control for Underactuated Aerial Flexible JointRobots Manipulators
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The control of an aerial flexible joint robot (FJR) manipulator system with underactuation is a difficult task due to unavoidable factors, including, coupling, underactuation, nonlinearities, unmodeled uncertainties, and unpredictable external disturbances. To mitigate those issues, a new robust fixed-time sliding mode control (FxTSMC) is proposed by using a fixed-time sliding mode observer (FxTSMO) for the trajectory tracking problem of the FJR attached to the drones system. First, the underactuated FJR is comprehensively modeled and converted to a canonical model by employing two state transformations for ease of the control design. Then, based on the availability of the measured states, a cascaded FxTSMO (CFxTSMO) is constructed to estimate the unmeasurable variables and lumped disturbances simultaneously in fixed-time, and to effectively reduce the estimation noise. Finally, the FxTSMC scheme for a high-order underactuated FJR system is designed to guarantee that the system tracking error approaches to zero within a fixed-time that is independent of the initial conditions. The fixed-time stability of the closed-loop system of the FJR dynamics is mathematically proven by the Lyapunov theorem. Simulation investigations and hardware tests are performed to demonstrate the efficiency of the proposed controller scheme. Furthermore, the control technique developed in this research could be implemented to the various underactuated mechanical systems (UMSs), like drones, in a promising way.

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Publication Date
Wed Jul 06 2022
Journal Name
Journal Of Al-qadisiyah For Computer Science And Mathematics
Pixel Based Techniques for Gray Image Compression: A review
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Currently, with the huge increase in modern communication and network applications, the speed of transformation and storing data in compact forms are pressing issues. Daily an enormous amount of images are stored and shared among people every moment, especially in the social media realm, but unfortunately, even with these marvelous applications, the limited size of sent data is still the main restriction's, where essentially all these applications utilized the well-known Joint Photographic Experts Group (JPEG) standard techniques, in the same way, the need for construction of universally accepted standard compression systems urgently required to play a key role in the immense revolution. This review is concerned with Different

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Publication Date
Sun Jun 07 2015
Journal Name
Baghdad Science Journal
Potential Energy Expectation Value for Lithium Excited State (1s2s3s)
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The purpose of the present work is to calculate the expectation value of potential energy for different spin states (??? ? ???,??? ? ???) and compared it with spin states (??? , ??? ) for lithium excited state (1s2s3s) and Li- like ions (Be+,B+2) using Hartree-Fock wave function by partitioning techanique .The result of inter particle expectation value shows linear behaviour with atomic number and for each atom and ion the shows the trend ??? < ??? < ??? < ???

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Publication Date
Tue Jul 30 2024
Journal Name
Academia Open
Positioning Preterm Newborns for Cardiorespiratory Stability A Global Insight
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Publication Date
Tue Oct 01 2013
Journal Name
2013 Ieee International Conference On Systems, Man, And Cybernetics
AWSS: An Algorithm for Measuring Arabic Word Semantic Similarity
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Publication Date
Sun Jan 01 2017
Journal Name
Proceedings Of The Conference “recent Trends In Engineering Sciences And Sustainability”, Baghdad
GNSS positioning techniques for enhancing Google Earth data quality
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Due to the easily access to the satellite images, Google Earth (GE) images have become more popular than other online virtual globes. However, the popularity of GE is not an indication of its accuracy. A considerable amount of literature has been published on evaluating the positional accuracy of GE data; however there are few studies which have investigated the subject of improving the GE accuracy. In this paper, a practical method for enhancing the horizontal positional accuracy of GE is suggested by establishing ten reference points, in University of Baghdad main campus, using different Global Navigation Satellite System (GNSS) observation techniques: Rapid Static, Post-Processing Kinematic, and Network. Then, the GE image for the study

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Publication Date
Tue Dec 01 2015
Journal Name
2015 9th Malaysian Software Engineering Conference (mysec)
Factors for communication technologies selection within virtual software teams
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Publication Date
Sat Oct 01 2022
Journal Name
Iraqi Postgraduate Medical Journal
Helicobacter Pylori Infection among Dyspeptic Patients Referred for Endoscopy
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Functional dyspepsia is one of the most common gastrointestinal symptoms and attributed to various causes including Helicobacter pylori infection. AIM OF THE STUDY: To correlate Helicobacter pylori infection to functional dyspepsia and to identify the possible risk factors for this infection. PATIENTS AND METHODS: Fifty patients who were referred to the endoscopy unit for dyspepsia symptoms, secondary gastric causes of dyspepsia were excluded during endoscopy, gastric biopsies were taken for histopathological study and for bedside urease test for detection of Helicobacter pylori infection. RESULTS: 62% of non-ulcer dyspeptic patients were infected with Helicobacter pylori, 74.2% of the patients were above 30 years old, female gender patient

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Publication Date
Thu Sep 15 2022
Journal Name
Romanian Neurosurgery
Coil migration during pressure-cooker technique for cerebral AVM
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Introduction: In recent decades, the endovascular treatment of cerebral arteriovenous malformations (AVMs) has advanced. However, it still carries risks of unanticipated complications. Coil migration is a reported complication of aneurysmal coiling procedures. Herein, we report a case of early intraprocedural coil migration during pressure cooker technique embolization of right thalamic AVM, discussing the management and potential explanations. The literature showed no report of coil migration after the pressure cooker technique in the form of coil-augmented Onyx injection technique (CAIT). Case description: An otherwise healthy 26-year-old female suddenly developed a severe headache with no loss of consciousness. Computed tomograp

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Publication Date
Sun Dec 07 2008
Journal Name
Baghdad Science Journal
Polar Gap Properties for Neutron StarWithin Light Cylinder Limits
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The huge magnetic fields of neutron star cause the nuclei of the stellar surface to form a tightly bound condensed layer. In this research some characteristics of polar gap and magnetosphere enclosed the star according to Sturrock Model were illustrated, positrons move out along the open field lines, and electrons flow to the stellar surface as in the related to Sturrock model. The magnetic field within polar gap areas, which is defined by the Irvin Radius (RL) decreases due to the expansion of the polar, resulting from the physical motion of the accreted material. The values of height gap at different distances from the star were estimated. The obtained results improve the most energetic positrons those with E? Emax radiate away their ener

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Publication Date
Sun Jul 23 2023
Journal Name
Al-rafidain Journal Of Medical Sciences ( Issn 2789-3219 )
Future of Engineered Phage Therapy for Clostridium difficile Infections
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Bacteriophages have the potential to eliminate both antibiotic-resistant and sensitive bacteria; as a result, they have become a major focus of such research. In contrast to antibiotics, which assault the entire bacterial population without discrimination, bacteriophages have a limited set of characteristics that allow them to target infectious microbes while avoiding friendly species (commensal microbiota). Nevertheless, large groups of naturally occurring bacteriophages that are well-differentiated and selective for the most clinically recognized pathogenic bacterial strains are required. Utilizing genetic engineering techniques that modify the target phage genome to synthesize phages with known characteristics in a brief period o

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