Competitive examination preparation takes enormous efforts & time on the part of a student to learn, practice and master each unit of the syllabus. To check proficiency level in each unit, student must take self-assessment to identify his/her weak areas to work upon, that eventually builds confidence to win. Also performance of a student in exam improves significantly if student is familiar with the exact nature, type and difficulty level of the questions being asked in the Exam. With this objective in mind, we are presenting before you this book containing unit tests. Some features of the books are- The complete syllabus is divided into logical units and there is a self- assessment tests for each unit. Tests are prepared by subject experts who have decade of experience to prepare students for competitive exams. Tests are as per the latest pattern of the examination. Detailed explanatory solution of each test paper is also given. Student is advised to attempt these Tests once they complete the preparation/revision of unit. They should attempt these Test in exam like environment in a specified time. Student is advised to properly analyze the solutions and think of alternative methods and linkage to the solutions of identical problems also. We firmly believe that the book in this form will definitely help a genuine, hardworking student. We have put our best efforts to make this book error free, still there may be some errors. We would appreciate if the same is brought to our notice. We wish to utilize the opportunity to place on record our special thanks to all faculty members and editorial team for their efforts to make this book.

Advances in Information Storage Systems (AISS), volumes 9 & 10, are special volumes which contain selected papers regarding not only information storage but also information equipment in general and related technologies. The papers were presented at the International Conference on Micromechatronics for Information and Precision Equipment (MIPE '97). MIPE '97 was held in Tokyo, Japan, from 20 to 23 July 1997, as one of the memorial events of the Centennial Grand Congress of the Japan Society of Mechanical Engineers.Information and precision equipment is fast-changing high technology, and is necessary for the development of an international multimedia society and essential for the innovation of conventional machines as well as the creation of new sophisticated machines for future medical, biological and cosmic industries in the 21st century. Information and precision equipment can improve their performances by analyzing, designing, fabricating, controlling and then utilizing a smaller and smaller world in space and time. Micromechatronics is not only a major interdisciplinary engineering but also the principle of innovation in such machines.In the light of this, the scope of MIPE '97 ranged from the micromechanics and micromechatronics of information storage, input/output devices, and precision equipment to microtechnologies related to information equipment. The papers in AISS special volumes are mainly related to information storage, particularly magnetic recording storage. But some of them are related to printer, paper-feeding-mechanism and micromachine technologies, which will directly or indirectly contribute future information devices. The papers contained in this series are of international archival quality and are refereed according to rigorous journal standards.Volume 9 contains papers on the mechanics and tribology of magnetic recording storage systems (mainly hard disk drives), while papers on the micromechatronics of the head-positioning system in magnetic disk storage are compiled in Volume 10 together with papers on optical disk storage and others.