Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

Browse

Filters

2003 - 200922010 - 20201

Settings

Publisher: search.filters.publisher.ElsevierSubject: search.filters.subject.Stability

Search Results

Now showing 1 - 3 of 3
  • Conference Object
    Citation - Scopus: 2
    Adaptive Actuator Failure Compensation for Concurrently Actuated Manipulators
    (Elsevier, 2003) Keçeci, Emin Faruk; Tang, Xidong; Tao, Gang
    This paper presents an adaptive actuator failure compensation method, which compensates for uncertainties due to unknown actuator failures and system dynamics, for a class of redundant manipulators where some joints concurrently actuated. Physical realization of concurrently actuated manipulators and their advantageous of use have been understood before, but adaptive failure compensation is still an open issue. In this research, failure formulation, controller structure and adaptive update rules for handling uncertainties from both the system dynamics and the failures are studied. The system stability is shown by a modified Lyapunov. Simulation results show the effectiveness of the proposed adaptive failure compensation control design.
  • Conference Object
    Adaptive Actuator Failure Compensation for Cooperating Multiple Manipulator Systems
    (Elsevier, 2003) Keçeci, Emin Faruk; Tang, Xidong; Tao, Gang
    This paper presents adaptive actuator failure compensation for a cooperating multiple manipulator system with uncertain actuator failures in the task space. Advantages of designing control schemes in task spaces are emphasized, applications of task space control in robotics are discussed and a short review on control algorithms for cooperating multiple manipulator systems is given. Dynamic equations of motion of the multiple manipulator system in the task space are derived, and the adaptive actuator failure compensation problem is formulated. A compensation controller structure is proposed, for which adaptive parameter update laws are developed. The adaptive control scheme is able to compensate for the uncertainties arising from both the system parameters and the actuator failures. Based on Lyapunov stability analysis, the closed-loop signal boundedness and the convergence of the tracking error to zero are ensured. © 2003 International Federation of Automatic Control.
  • Article
    Citation - WoS: 13
    Citation - Scopus: 15
    Analysis of Dilution Induced Disintegration of Micellar Drug Carriers in the Presence of Inter and Intra Micellar Species
    (Elsevier, 2020) Polat, Hürriyet; Kutluay, Gülistan; Polat, Mehmet
    Micelles of self-assembling polymeric surfactant molecules are promising nanoscopic carriers for lipophilic and toxic drugs, genes, and imaging molecules. Though it is a must for successful transport, ensuring micelle integrity is a challenge during intravenous injection where micelles must endure abrupt dilutional effects and encounters with native molecules. Therefore, direct observational evidence of how micelles behave during dilution is valuable in manipulating the designs of these carriers for a succesful drug delivery. Morphology and stability of the barren and a drug-loaded (lipophilic probucol) micelles of a polymeric surfactant (Pluronic® P123) were monitored during systematic re-dilution in distilled water and simulated body fluid in the presence of a model protein (bovine serum albumin). It was observed through surface tension, dynamic light scattering, laser velocimetry, transmission scanning and transmission electron microscopy, and atomic force microscopy analyses that the micelles disintegrated to various degrees in all cases upon dilution. The results indicate that dilution effects must be taken into account in designing micellar drug carriers. The assistance of some other means of protection such as encapsulation should be considered for ensuring micelle integrity within the bloodstream. © 2020 Elsevier B.V.