Fall 2020 The BRIDGE LINKING ENGINEERING AND SOCIETY 50th ANNIVERSARY ISSUE 2020 The BRIDGE NATIONAL ACADEMY OF ENGINEERING Donald C. Winter, Chair John L. Anderson, President Corale L. Brierley, Vice President Carol K. Hall, Home Secretary James M. Tien, International Secretary Martin B. Sherwin, Treasurer Editor in Chief: Ronald M. Latanision Managing Editor: Cameron H. Fletcher Production Associate: Penelope Gibbs The Bridge (ISSN 0737-6278) is published quarterly by the National Acad emy of Engineering, 2101 Constitution Avenue NW, Washington, DC 20418. Periodicals postage paid at Washington, DC. Vol. 50, No. S, Winter 2020 Postmaster: Send address changes to The Bridge, 2101 Constitution Avenue NW, Washington, DC 20418. Changes of address or requests to unsubscribe should be sent to
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