SADHANA - Academy Proceedings in Engineering Sciences - is a monthly research journal in English published by the Indian Academy of Sciences. The journal covers all branches of Engineering Science including mechanics (fluid, solid, thermal), computer science, electronics, energy, aerospace technology, materials science, nuclear engineering, systems analysis, alternative technologies etc. The editorial board wishes particularly to encourage papers, (i) likely to be of interest to more than one professional group, either because the work is fundamental or because it reflects the best in current technology. (ii) summarising, at a sufficiently technical level, work done on special projects of interest to engineering scientists. (iii) offering extensive critical reviews, especially on subjects of interest in the country. The criteria for acceptance of papers in the journal are therefore breadth of interest, irrespective of whether the paper reports research or development, theory or experiment, original work or review, and quality of work reported and its presentation (text, diagrams etc.). Papers on developments in Indian technology must pay special attention to the problems peculiar to the country in such projects