This paper presents fundamental results about how zero-curvature (paper) surfaces behave near creases and apices of cones. These entities are natural generalizations of the edges and vertices of piecewise-planar surfaces. Consequently, paper surfaces may furnish a richer and yet still tractable class of surfaces for computer-aided design and computer graphics applications than do polyhedral surfaces.

It is shown by several examples that if D. A. Huffman's pulse train design is modified to allow one nonzero pair of sidelobes in addition to the unavoidable end sidelobes in the autocorrelation function, then a substantial increase in the central peak for the same maximum pulse energy can be achieved.

The necessary and sufficient conditions for a function to be the autocorrelation function of a waveform consisting of a finite length train of pulses of various amplitudes is derived. The number of pulse trains having a given realizable autocorrelation function is determined. An "impulse-equivalent" pulse train is defined as one that yields, as closely as is theoretically possible, the same autocorrelation function that a single pulse gives. It is shown that impulse-equivalent pulse sequences exist for all lengths; the number of classes of these sequences is exponentially related to their length. It is demonstrated that all impulse-equivalent pulse trains can be generated by exciting a linear digital filter with two input pulses that correspond in time to the initiation and to the termination of the desired output sequence.

An important class of finite-state machines transforms input sequences of digits into output sequences in a way such that, after an experiment of any finite length on the machine, its input sequence may be deduced from a knowledge of the corresponding output sequence, its initial and final states, and the set of specifications for the transformations by which the machine produces output sequences from input sequences. These machines are called "information-lossless." Canonical circuit forms are shown into which any information-lossless machines may be synthesized. The existence of inverses for these circuits is investigated and circuits for their realization are derived.

article Share on The Design and Use of Hazard-Free Switching Networks Author: David A. Huffman Massachusetts Institute of Technology, Cambridge, Massachusetts Massachusetts Institute of Technology, Cambridge, MassachusettsView Profile Authors Info & Claims Journal of the ACMVolume 4Issue 1pp 47–62https://doi.org/10.1145/320856.320866Published:01 January 1957Publication History 92citation1,232DownloadsMetricsTotal Citations92Total Downloads1,232Last 12 Months349Last 6 weeks108 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteeReaderPDF

A linear binary filter has as its output a binary sequence, each digit of which is the result of a parity check on a selection of preceding output digits and of present and preceding digits of the filter input sequence. The terminal properties of these filters may be described by transfer ratios of polynomials in a delay operator. If two binary filters have transfer ratios which are reciprocally related then the filters are mutually inverse in the sense that, in a cascade connection, the second filter unscrambles the scrambling produced by the first. The coding of a finite sequence of binary information digits for protection against noise may be accomplished by a binary sequence filter, the output of which becomes the sequence to be transmitted. (The inverse filter is utilized at the receiver.) Into the filter at the transmitter is inserted a sequence of information digits, immediately followed by another sequence of completely predictable digits consisting, say, of zeros. The completed block of digits is scrambled in a linear filter before transmission through the noisy channel. If this scrambled sequence were unaffected by noise in the channel the result of unscrambling by the receiver filter would be the original sequence of information digits followed by the all-zero sequence. If, however, channel noise has been added to the sequence put into the receiver filter, then its output is the original sequence, plus the response of the receiver filter to the noise superimposed thereon. In particular, the sequence positions which would have contained all zeros, had there been no noise, will now contain digits whose values are related to the sequence position affected by the noise. These data may then be utilized for the subsequent correction of the errors which would otherwise have been caused by the noise.