Isfahan University of Thechnology
Computational Methods in Engineering
22287698
24235741
16
1
1997
7
1
An Application of Cluster Analysis Technique in Educational Planning
1
18
Seyed H. IranManesh and Seyed T. A. Niaki
In this paper an application of the cluster analysis technique in educational planning is demonstrated by means of a developed computer software with some characteristics of an expert system. The main idea is based on the knowledgebased systems which have been applied in group technology. The software is applied to weekly schedules of the courses and professors of the Industrial Engineering Department of Sharif University of Technology. The results show that the technique can be applied to reduce the number of variables and constraints of a zeroone programming model of an educational planning (a typical example of an assignment problem).

http://jcme.iut.ac.ir/article199en.html
http://jcme.iut.ac.ir/article199en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
22287698
24235741
16
1
1997
7
1
TwoDimensional BoundaryConforming Orthogonal Grids for External and Internal Flows Using SchwarzChristoffel Transformation
19
29
S. H. Mansouri
S. M. Hosseini Sarvari
A. Keshavarz and M. Rahnama
In this paper, a SchwarzChristoffel method for generating twodimensional grids for a variety of complex internal and external flow configurations based on the numerical integration procedure of the SchwarzChristoffel transformation has been developed by using Mathematica, which is a general purpose symbolicnumericalgraphical mathematics software. This method is highly accurate (fifth order) with mesh size, and is highly flexible for treatment of complex internal flow geometries, for a high degree of control of mesh spacing, and for generation of either orthogonal or nonorthogonal grids. In addition, this method directly generates twodimensional incompressible potential flow solutions for internal flow, and simply or symmetrical multiply connected external flows: it generates a C type grid for a general multiply connected twodimensional external flow. The capabilities of this method has been shown by sample cases including external flow over symmetric and antisymmetric airfoils, a car profile, and internal flows with arbitrary shapes. To facilitate further applications, a computer program using Mathematica software has been developed.

http://jcme.iut.ac.ir/article1100en.html
http://jcme.iut.ac.ir/article1100en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
22287698
24235741
16
1
1997
7
1
DEXSY2 A Dental Expert System for Diagnosis and Treatment
31
39
M. Fahimi and M. Yarandi
DEXSY2 is a dental expert system, which diagnoses oral diseases and offers a treatment course. The system which is designed and implemented from scratch is capable of diagnosing among thirty five oral diseases and offering a course of treatment for each. It uses a decision tree for its representation of knowledge, and each of its nodes contains a frame. The knowledge base of the system contains a tree for diagnosing the diseases, a tree for its drug treatment, and a set of signs used in the diagnosis and treatment. Reasoning in the system is based on a forward chaining and depthfirst search of the tree. It takes into consideration the uncertainties involved and avoids asking repetitive questions. DEXSY2 also diagnoses a combination of diseases. It also provides various explanations for its decisions.

http://jcme.iut.ac.ir/article1101en.html
http://jcme.iut.ac.ir/article1101en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
22287698
24235741
16
1
1997
7
1
Method of Quantitative Phase Analysis by XRD Without Reference Material
41
49
A. Monshi
This new method which is worked out in Isfahan University of Technology, makes it possible to analyze the phases quantitatively in minerals and powdered materials by X Ray Diffraction and without any reference material. To identify n unknown phases, n different combinations of phases, from fine and coarse fractions, or etc., must be obtained. Amorphous phases should not exist. Intensity ratios of selected peaks of different phases to the suitable peak of added substances are plotted against the weight ratio of unknown material to substances. The phase is used to eliminate the effect of absorption in measurements. After detecting the slopes of linear plots which pass through the origin, n equations are obtained which are solved for n unknown coefficients. The quantitative phase analysis is subsequently performed in all n samples. If reference materials are available for some phases, n is reduced. The method is to analyze three phases MgO, CaO, Ca(OH)2 with substance CaF2, in magnesite – dolomite, partially hydrated refractories.

http://jcme.iut.ac.ir/article1102en.html
http://jcme.iut.ac.ir/article1102en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
22287698
24235741
16
1
1997
7
1
Analysis of Power Electronic Converters Using the Developed State Space Averaging Method
51
65
J. Mahdavi and A Emaadi
Power electronic converters are nonlinear timedependent systems whose exact analysis without the use of computers is very difficult, and even using computer softwares requires a long time. Use of the state space averaging method, as will be mentioned, in addition to simplifying the analysis procedure which is a result of converting a timedependent system to a timeindependent one, reduces the required computation time considerably. But this method is not applicable to circuits for which small variations of state variables does not apply, since it is not able to follow rapid and large changes. Therefore, we make use of a developed method in which we consider the average of the state variables as well as adding the harmonics. This more general method can basically be adjusted to various arbitrary wave forms, and is based upon a Fourier series timedependent display for a sliding window of the given waveform. In this paper, after introducing the developed state space averaging method, results of applying this method to various basic DC/DC and DC/AC converters will be mentioned, and also effects of some parameters on the quality of model will be discussed.

http://jcme.iut.ac.ir/article1103en.html
http://jcme.iut.ac.ir/article1103en.pdf
Isfahan University of Thechnology
Computational Methods in Engineering
22287698
24235741
16
1
1997
7
1
The Stability and Thermal Performance of a Small Solar pond
67
75
A. A. Bidokhti and A. R. Mohamadnejad
A small salt gradient solar pond with an average surface area of 1.8 m2 and depth of 0.8m has been tested. The depths of storage, gradient and surface zones are 0.3, 0.27 and 0.07m, respectively. The temperature of the storage zone for the summer days reaches its maximum of 65˚ C after about 8 days. Daily variation of the storage zone temperature was about 8˚C which is due to small volume of this zone. The thermal absorption of the pond varies between 35 to 20 percent of the total solar radiation, depending on the temperature of the storage zone. Salinity of the storage zone is about 200 gr/kg and the density gradient of the gradient zone is about 5x103 gr/cm4 which with typical fluid velocity of the convective zone gives a Richardson number, Ri, of order of 104. Erosion of the gradient zone based on this Ri is about 2.5 cm/month which is in agreement with the observations. Although the temperature of the storage zone reaches high values, with sloped wall, no sign of double diffusive convection was observed.
http://jcme.iut.ac.ir/article1104en.html
http://jcme.iut.ac.ir/article1104en.pdf