فصلنامه علوم و فناوری دریا
سال دوازدهم شماره 48 (زمستان 1387)

The seamen at sea to meet with different important missions and face crises in sea sand Since teaching in control and advent of crisis plays a major role, this article has engaged in the study of the relationship of naval practical teachings with the management of the naval crisis. On this basic, the theory of the research is a relationship between the naval practical teaching of the students in naval Universities and the management of the crisis. the method used is descriptive-correlative and collection data is a question naire, for analyze used inferential descriptive statistics. On this basis, out of 691 persons from Commanders of the navy, according to the table of kerjesy, 248 persons were randomly chosen in the form of ranking and the study of the theories of the research were carried out, and the theory of the research was confirmed with the 99% assurance.

In this paper we have studied multiple targets tracking in sonar systems. There are several algorithms for this purpose but only a few of them can be applied for targets with nonlinear movement. We have proposed a new and optimum algorithm for multiple targets tracking with nonlinear distribution. The accuracy of this algorithm is good and its running time is short enough. In this algorithm we have used new mathematics theorems. The algorithm used in this paper is based on Rao-Blackwellized filtering theorem which is one of the latest mathematics theorems used in signal processing

In this research a 2D model was developed to predict water level changes due to storm considering atmospheric pressure and wind stress. This model was used to simulate storm surge in Oman Sea. For boundaries of system three National Geographical Organization Merkatour Maps of 2837, 2838 and 2851 was used. The maps had a scale of 1:75000 with an Origin of coordinate coincidence of 200 latitude. To simulate the boundaries in Cartesian coordinate two digits of 0 and 1 was used to identify water and land respectively. To do this after simulating boundaries and interpolating the topographic lines of Oman Sea domain using developed code, the dynamic equations of system i.e. 2D nonlinear shallow water equations was solved using implicit and semi implicit methods. To validate the model the results of Roed & Copeer (1987) was employed for two simulated wind stresses on two rectangular and parallelogram domains with different boundary conditions. Finally the model was run on Oman Sea domain and the results was examined and discussed.

Steady state hydrodynamic force due to forced harmonic rigid-body motions is called added mass. To study ship motions’ characteristics (seakeeping & maneuvering) usually it is needed to have added mass coefficients of ship sections. Determination of added mass in deep water for bodies of cylindrical and elliptical sections is possible by using Schwarz-christoffel mapping. Consideration of bottom effects in shallow water is usually done by using method of images in limited bounadry condition. In this paper a general method for calculation of added mass (coefficient) using Schwarz-christoffel mapping is presented. Added mass of some elliptical sections is calculated and new results are presented. Results are compared to the previous available results.

The natural vibrations of clamped annular isotropic sector plates are analyzed using the Extended Kantorovich Method (EKM). A conformal mapping is used to transform a sector with identified geometry to a rectangular plate which the solution is available in literature and solved by Dalaei and Kerr [1] using EKM. The developed iterative scheme converges very rapidly to the final result. The obtained natural frequencies are evaluated for annular sector plate and the obtained results are compared with those published by Leissa [6] and a simulation done by the finite element method (FEM). The agreement found to be very close. As there are no exact analytical solutions for clamped annular sector plates, the generated method for the natural modes, and the corresponding natural frequencies, are very suitable for use in engineering analysis.