Showing 25 results for Control
A. Hosseini, M. Keshmiri, and M. J. Sadigh,
Volume 26, Issue 1 (7-2007)
Abstract
The optimal path planning of cooperative manipulators is studied in the present research. Optimal Control Theory is employed to calculate the optimal path of each joint choosing an appropriate index of the system to be minimized and taking the kinematics equations as the constraints. The formulation has been derived using Pontryagin Minimum Principle and results in a Two Point Boundary Value Problem, (TPBVP). The problem is solved for a cooperative manipulator system consisting of two 3-DOF serial robots.
M. Sheikhzadeh, K. Matin, M. G. Tafreshi,
Volume 26, Issue 1 (7-2007)
Abstract
The aim of this research is to design a controlling loop that eliminates the irregularities in yarn tension during the winding process. In order to achieve this, we employed a relative feedback industrial control system. The yarn tension sensor measures the tension. Its output is analyzed in the automatic controlling unit. This unit adjusts the tension level according to feedback signals, thus adjusting the yarn tension to the desired value. The yarn package wound using this system will additionally experience the least yarn tension variations.
A. Eslami, H. Modaraei, and H. Ahmadi,
Volume 26, Issue 2 (1-2008)
Abstract
A. Arkan, and S.r. Hejazi,
Volume 27, Issue 2 (1-2009)
Abstract
Supply chain coordination has become a critical success factor for supply chain management (SCM). In the past few years, the researchers have widely emphasized that cooperation among supply chain (SC) firms is a key source of competitive advantage. This paper is focused on supply chain coordination from the perspective of inventory management. Li and Liu [1] developed a model for illustrating how to use quantity discount policy by price adjustment mechanism to achieve supply chain coordination. We extend this mechanism to three echelon supply chain and consider variable lead time which has more
representation of the real world situation. For this purpose, we will develop a model with benefit objective function for the problem. We will then analyze the model with and without coordination. By solving the proposed model, proper order quantities will be obtained. Finally, the advantages of the proposed mechanism will be explored and a surplus benefit dividing method will be designed.
S. Ghadiri, A. Hassanzadeh-Tabrizi,
Volume 37, Issue 1 (6-2018)
Abstract
In this study, the synthesis of nano-porous calcium magnesium silicate was performed and studied to improve drug properties and drug release. This synthesis was carried out by using the tetraethyl ortho silicate precursor (TEOS) and the Cetyltrimethyl ammonium bromide surfactant (CTAB) in a sol-gel alkaline environment; and the product was heat treated at 600° C and 800° C temperatures. The purpose of this study is to investigate the effect of the calcination temperature on the potential for ibuprofen release by the production produced compound. The product was studied using X-ray diffraction patterns (XRD), Nitrogen adsorption / desorption, Fourier-transform infrared spectroscopy (FTIR), ultraviolet spectroscopy (UV) and Transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM). The results of Nitrogen absorption-desorption assay showed a surface area of 42-140 m2 /g The drug release after 240 hours showed that the calcite sample had a lower release at 600 ° C, temperature that which was is due to the smaller size of the cavities and the more surface area, as compared tothan the other specimens. Also, calcium and magnesium elements increased the loading capacity, and createcreating a suitable substrate for for the slower drug release. Overall, This this study showed that nano-porous magnesium silicate calcium has had the ability to load and release the ibuprofen and can could be, therefore, used as a modern drug delivery system in the bone tissue engineering field.
