Showing 4 results for Kazemzadeh
A. Keshavarzi and M. J. Kazemzadeh Parsee,
Volume 24, Issue 1 (7-2005)
Abstract
Flow separation at water intake is the main cause of head loss and flow discharge reduction.
As a result, study of shape and size of separation is very essential when designing an optimum water intake. Water intake is normally built with a 90 degree angle to the main channel flow direction. However, the flow structure in this type of water intake consists of large separation size along with vortex generation. In this study, the effect of the ratio of discharge at water intake to the main channel discharge (Qr) on the location and size of separation is investigated numerically and experimentally. The velocity of the flow at each point is measured in two dimensions using electromagnetic velocity meter. The results from the experimental data indicate that the location and shape of separations are a function of flow discharge ratio (Qr). These results also indicate that at higher ratios of flow discharge, the separation occurs downstream the water intake, whereas at lower flow discharges, the flow separation occurs upstream the water intake. Additionally, the capabilites of numerical turbulence computation models including standard k-e and RNG k-e models are investigated in this study. The computed flow velocity from the turbulence models showed that the result of standard k-e model is approximately close to the experimental data when compared with RNG k-e model
R.b.kazemzadeh, R.noorossana and M. Karbasian,
Volume 24, Issue 2 (1-2006)
Abstract
In the last few years, Run-to-Run (R2R) control techniques have been developed and used to control various processes in industries. These techniques combine response surface, statistical process control, and feedback control techniques. The R2R controller consists of a linear regression model that relates input variables to output variables using Exponentially Weighted Moving Average (EWMA). In this paper, we have developed a R2R controller model based on quality costs. The model consists of finding optimum weight of EWMA procedure in R2R controllers with respect to conformities and
nonconformities costs. The validity and performance of the developed model were tested using a real case study in an optic industry application.
F. Daneshmand, M. Farid, and M.j. Kazemzadeh-Parsi,
Volume 27, Issue 2 (1-2009)
Abstract
In this paper, a modification on the fixed grid finite element method is presented and used in the solution of 2D linear elastic problems. This method uses non-boundary-fitted meshes for the numerical solution of partial differential equations. Special techniques are required to apply boundary conditions on the intersection of domain boundaries and non-boundary-fitted elements. Hence, a new method is also presented for the computation of stiffness matrix of boundary intersecting elements and boundary conditions of higher accuracy are applied. In order to examine the applicability of the proposed method, some
numerical examples are solved and the results are compared with those obtaioned from both fixed grid finite element and standard finite element methods.
M. H. Barounian, S. Hesaraki, A. Kazemzadeh,
Volume 37, Issue 1 (Journal of Advanced Materials-Spring 2018)
Abstract
In this study, a new bioactive and light-cure polymeric calcium phosphate nanocomposite containing a powder phase consisting of pure TetraCalciumPhosphate was synthesized by solid state sintering. By using indomethacin, a non-steroidal anti-inflammatory drug, and a liquid phase including polyhydroxy-based resin, Ethyl Methacrylate was prepared and evaluated after curing with the high-intensity blue light. Phase changes in the cement composition after soaking in phosphate buffered saline (PBS) were investigated using X-ray diffraction (XRD). Morever, changes in the chemical groups in the cement and the microstructure of the cement after soaking in the PBS were investigated by Fourier transform spectroscopy (FTIR) and electronscanning microscopic (SEM) images, respectively. XRD patterns and SEM images showed that after soaking the samples in. the PBS solution, a new calcium phosphate phase with a shape like needle and polka appeared on the surface, which was formed more in the drug-containing sample at a concentration of 5% wt. of these nanostructures. Other results also showed that with the passage of time, the structural degradation in the PBS was due to the conversion of the initial phases to the calcium phosphate phase (apatite). Also, the results of the mechanical strength test of polymeric cement samples containing the drugshowed that the mean compressive strength of the samples after the fixation was about 56 MPa, and it was decreased by 26 MPa with continuous immersion after 21 days.
