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in the Indian Ocean, in terms of loss of life and damage. Numerical simulation was made for three tsunamis, the December 26, 2004, event, the Sumatra tsunami of 1833, and a hypothetical tsunami originating in the Andaman-Nicobar region. Since inundation is not included in these simulations, the tsunami amplitudes were deduced at the 10m depth contour in the ocean, off several locations on the coast of Tamil Nadu. The computed amplitudes appear reasonable as compared to known tsunami amplitudes from past events. A numerical simulation of December 26, 2004, tsunami and propagation to the coast of Tamil Nadu, India (Figure 1) is carried out using the SWAN code [1] implementation under MIRONE v0.7 suite [2]. The source parameters were chosen similar to that of Watts et al.[3] with four segments extending from north Sumatra to north Andaman. The bathymetry data grid of 1 minute resolution for Indian Ocean region (30E 130E 30N 70S) is extracted from the blend version of GEBCO and S&S satellite bathymetry grid data [4]. A 3 minute grid is derived for the above region by bi-cubic interpolation and subsequently used for all our simulations. This grid size is chosen due to computer resource constraints for the large area chosen for simulations.The station markers are fixed at about 2-3 km east of each station (Figure 2) so that at least about 10 m depth is available at station points as required for SWAN simulations. In this simulation, inundation of the coast by the tsunami was not included and this will be done in a future study, hence all the tsunami amplitudes are shown at 10 m depth contour in the ocean.

In Prototype Fast Breeder Reactor, which is under construction, a dedicated Safety Grade Decay Heat Removal (SGDHR) is employed for removing decay heat during shut down (in case the normal path is not available). Each SGDHR loop consists of a sodium to sodium heat exchanger (DHX) and sodium to air heat exchanger (AHX). Two types of AHX are employed for diversity and this paper discusses creepfatigue damage evaluation of a special type of sodium to air exchanger. It is a vertical cross flow type heat exchanger with finned tubes connecting two toroidal sodium headers. Five different types of tube configurations, each 50 in numbers (total 250 Nos.) connect both the headers and the entire component is supported through the top header with the bottom outlet header floating. During the normal reactor operating conditions the sodium temperature at the hot end is nearly 823 K. The normal operation, SGDHR operation and shut down condition lead to cyclic thermal stresses. 3-D analyses of the exchanger have been completed for self weight, pressure and thermal loadings. The FEM code CAST-3M, issued by CEA France has been used. The toroidal header has been modeled using shell elements and all the tubes are modeled using pipe elements. The peak stress at the critical junction is 96.4 MPa. The resulting fatigue damage is found to be negligible and the total creep damage is estimated as 0.88 which is conservative, as the stress relaxations are not accounted in the analysis. More details are discussed in the paper.

The accuracy of the servo system is dependent on the speed or band width of the closed loop control system. To achieve the high speed closed loop operation, hardware oriented control is preferred and it is achieved by means of an ASIC (Application Specific Integrated Chip). The servo system is used to drive a two axis robotic arm moving in a plane where two PMSM motor with servo control provides the required motion. Robotic applications require quick and accurate changes in driving torque so that the required motion behaviour is attained. Quick change in operating flux is required for fast and accurate servo control. Conventional scalar control drives cannot achieve quick response time and hence vector control is employed. The IRMCK201 ASIC used in the application has the Vector Control algorithm hard wired into it for complete servo control of a single PMSM. It takes the position and current feed back by using shaft encoder, hall sensor and IR2175 Current sensing IC. It can set up communication with a host controller through either high speed serial, SPI or Parallel protocols. The inverter unit is implemented using an Intelligent Power Module (IPM) and it is driven by the Space Vector Modulation signals from IRMCK201. The work shows that highly efficient servo drive can be implemented using IRMCK201 and Host controller with PMSM.