moayed mohseni

Giesekus viscoelastic fluid is solved analytically for purely tangential flow in a concentric annulus at laminar and steady state conditions. Flow is created by a relative rotational motion between the cylinders. The analytical expressions for yield dimensionless velocity profile, pressure distribution, (f and Re are Fanning friction factor and Reynolds number) and material functions (viscosity, first and second normal stress difference coefficients) are obtained in cylindrical coordinates. Results show that difference between the values of lower as well as upper critical limits of the velocity ratio (where the minimum velocity happens) with their corresponding Newtonian values increase when mobility factor and Deborah number increase. The results also show that viscometric functions decrease by increasing elasticity because the viscoelastic fluid shows the shear thinning behavior which is strengthened by increasing elasticity. It is found that, for all values, profiles are symmetrical around (  and k are velocity ratio and radius ratio) because no relative motion exists.

Following the "Integration Program" of general physician training curriculum recommended by the Department of Medical Education of Iranian Ministry of Health and Medical Education, several concerns raised towards the effect of this program. This study aimed to assess student's view towards integration of limb anatomy course to the pre-clerkship medical program in Iran. The study was conducted on 80 medical students enrolled in the third semester of medical program of Shahed University. Changes in the program according to the syllabus approved by the Supreme Council of Cultural Revolution. These changes include new content arrangement, integration of limb anatomy into pre-clerkship medical program, adding useful contents, methods of preparation prior to classroom theory and encouraging team learning. A questionnaire was used to collect students view about the integration program. Students found the integration useful in terms of content of the course (%83), learning effectiveness, lasting of knowledge %78.2, improved clinical skills %66.4, positive attitude toward anatomy %86.4, active participation in a group lesson %70/4 and ability to recall %79.6 respectively. The differences in content course and positive attitude were significant. Medical students showed agreement with this new method and recommended it for other specific courses.

The congestion management system is a systematic approach، collaboratively developed and implemented throughout a metropolitan region that provides for the safe and effective management and operation of new and existing transportation facilities through the use of demand reduction and operational management strat­e­gies. In this paper we try to present some points which should be investigated in congestion management problems. We calculate different kinds of congestion problems which may be occurred in our network. Here، the hybrid model is used to solve problems in the electricity market to solve the congestion problem in the network and Benders techniques is used together with an optimal power flow (OPF). In fact، by using of Benders algorithm the problem is divided into two major and minor problems. Therefore، the major problem related to the economy sector and no network is included and the minor problem is to solve the network and examine the accuracy of the network. Benders algorithm has been tested on a standard network IEEE 24 bus and Matlab software is used to implement the algorithm.