Ronald Martin Foster (3 October 1896 – 2 February 1998), was an American mathematician at

Bell Labs Nokia Bell Labs, commonly referred to as ''Bell Labs'', is an American industrial research and development company owned by Finnish technology company Nokia. With headquarters located in Murray Hill, New Jersey, Murray Hill, New Jersey, the compa ...

whose work was of significance regarding

electronic filter Electronic filters are a type of signal processing filter in the form of electrical circuits. This article covers those filters consisting of lumped-element model, lumped electronic components, as opposed to distributed-element filters. That ...

s for use on telephone lines. He published an important paper, ''A Reactance Theorem'', (see Foster's reactance theorem) which quickly inspired

Wilhelm Cauer Wilhelm Cauer (24 June 1900 – 22 April 1945) was a German mathematician and scientist. He is most noted for his work on the analysis and synthesis of electrical filters and his work marked the beginning of the field of network synthesis. Prio ...

to begin his program of

network synthesis filters In signal processing, network synthesis filters are filters designed by the network synthesis method. The method has produced several important classes of filter including the Butterworth filter, the Chebyshev filter and the Elliptic filter. ...

which put the design of filters on a firm mathematical footing. He is also known for the

Foster census In the mathematical field of graph theory, a graph is symmetric or arc-transitive if, given any two ordered pairs of adjacent vertices (u_1,v_1) and (u_2,v_2) of , there is an automorphism :f : V(G) \rightarrow V(G) such that :f(u_1) = u_2 a ...

cubic Cubic may refer to: Science and mathematics * Cube (algebra), "cubic" measurement * Cube, a three-dimensional solid object bounded by six square faces, facets or sides, with three meeting at each vertex ** Cubic crystal system, a crystal system w ...

symmetric graph In the mathematical field of graph theory, a graph is symmetric or arc-transitive if, given any two ordered pairs of adjacent vertices (u_1,v_1) and (u_2,v_2) of , there is an automorphism :f : V(G) \rightarrow V(G) such that :f(u_1) = u_2 a ...

s and the 90-vertex cubic symmetric

Foster graph In the mathematical field of graph theory, the Foster graph is a bipartite 3-regular graph with 90 vertices and 135 edges. The Foster graph is Hamiltonian and has chromatic number 2, chromatic index 3, radius 8, diameter 8 and girth 10. It is a ...

Education

Foster was a

Harvard College Harvard College is the undergraduate education, undergraduate college of Harvard University, a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Part of the Harvard Faculty of Arts and Scienc ...

graduate S.B. (Mathematics), summa cum laude, Class of 1917. He also received two honorary Sc.D.s."The Foster Census: R.M. Foster's Census of Connected Symmetric Trivalent Graphs", by Ronald M. Foster, I.Z. Bouwer, W.W. Chernoff, B. Monson and Z. Star (1988) .

Professional career

*1917 – 1943 Research & Development Department (later

American Telephone & Telegraph AT&T Corporation, an abbreviation for its former name, the American Telephone and Telegraph Company, was an American telecommunications company that provided voice, video, data, and Internet telecommunications and professional services to busi ...

, as a Research Engineer (Applied Mathematician), New York City, New York. *1943 – 1963 Professor and Head of Department of Mathematics,

Polytechnic Institute of Brooklyn The New York University Tandon School of Engineering (commonly referred to as Tandon) is the engineering and applied sciences school of New York University. Tandon is the second oldest private engineering and technology school in the United St ...

, Brooklyn, New York City, New York.

Publications

*Campbell, GA, Foster, RM, ''Fourier Integrals for Practical Applications'', "Bell System Technical Journal", pp 639–707, 1928. *Pierce, BO, Foster. RM. "A Short Table of Integrals", Fourth Edition, Ginn and Company, pp 1–189, 1956.

References

1896 births American men centenarians Scientists at Bell Labs American electronics engineers 20th-century American mathematicians Graph theorists Harvard College alumni 1998 deaths Polytechnic Institute of New York University faculty 20th-century American engineers {{US-mathematician-stub