In this paper, robust adaptive tracking control is proposed for the underwater robot in the presence of parametric uncertainties and unknown external disturbances. Backstepping control of the system dynamics is introduced to develop full state feedback tracking control. Using parameter adaptation, backstepping control and variable structure based techniques, the robust adaptive tracking control...

Background and Objectives: Studies have documented the morhplogical, neurochemical and functional difference between the dorsal and ventral zones of hippocampus. The aim of this study was to assess the effects of chronic diabetes mellitus type1 on ventral and dorsal zones of hippocampus. Methods: Experimental diabetes was induced by stereptozotocin at a dose of 60 mg/kg. At the end of 8 weeks t...

This paper examines the problem of link position tracking control for robot manipulators with input toque uncertainty. It is assumed that the input torque uncertainty can be regarded as dead-zone phenomena at each link of manipulator and all the system parameters for robotic manipulator and dead-zone model are unknown. The proposed method ensures that the unknown parameters are estimated adapti...

Due to the great technological improvement obtained in the last decades, it became possible to use robotic vehicles for underwater exploration. During the execution of a certain task with the robotic vehicle, the operator needs to monitor and control a number of parameters. If some of these parameters, as for instance the position and the orientation of the vehicle, could be controlled automati...

Bone remodelling models are widely used in a phenomenological manner to estimate numerically the distribution of apparent density in bones from the loads they are daily subjected to. These simulations start from an arbitrary initial distribution, usually homogeneous, and the density changes locally until a bone remodelling equilibrium is achieved. The bone response to mechanical stimulus is tra...

In the present study, the Weldability and microstructure of dissimilar welds of AISI 347austenitic stainless steel to ASTM A335 low alloy steel was investigated. For this purpose, gas tungsten arc welding process and two filler metals including ERNICr-3 and ER309L were used. After welding, the microstructure of the different zones of each joint, including weld metals, heat affected zone (HAZ) 1...

Protoplanets accrete material from their natal protostellar disks until they are sufficiently massive to open a gap in the face of the disk's viscosity that arises from the magneto-rotational instability (MRI). By computing the ionization structure within observationally well-constrained disk models, we demonstrate that poorly ionized, low viscosity " dead zones " stretch out to 12 AU within ty...

In this research, St37 and 316L steel sheets were welded using friction stir welding (FSW) process and effective parameters such as the rotational speed, linear speed of the tool, pin diameter, and their appropriate values were studied. The microstructure, hardness, and strength of the different welding regions were investigated. It was observed that in the stir zone (SZ), a mechanical operatio...