NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.
This study was supported by Contract HHM402-10-D-0036 between the Defense Intelligence Agency and the National Academy of Sciences. Any views or observations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the organizations or agencies that provided support for the project.
Limited copies of this report are available from the Division on Engineering and Physical Sciences, National Research Council, 500 Fifth Street, NW, Washington, DC 20001; (202) 334-2400.
Copyright 2013 by the National Academy of Sciences. All rights reserved.
Printed in the United States of America