lefkovitz david (8 résultats)

Hard Cover. Etat : Very Good. Etat de la jaquette : Very Good. First Edition. a very good hardcover in very good dustjacket; ; an ex-library copy with usual markings; internally pages bright and clean; ---------- SATISFACTION GUARANTEED --------- FAST, COURTEOUS SERVICE ------ ALL ORDERS SHIPPED WITH DELIVERY CONFIRMATION; Size: 6 x 9". Ex-Library.

Hardcover. Etat : Near Fine. Original black cloth. Near Fine in Very Good Dust Jacket with a small spot on the front cover and slight edge wear.

Hardcover. First Edition. Very Good in Very Good dust jacket; DJ is worn at edges. Previous owner's name. ; B&W Illustrations; 289 pages.

Etat : Good. Light wear to boards. Content is clean with minor age tone. DJ with some edge wear, fading to spine and creasing.

Cloth w/DJ. Etat : VG/G. Diagrams (illustrateur). New York, NY: Spartan Books. VG/G. (1969). . Cloth w/DJ. Sm 4to., 215 pp., DJ rubbed, frayed, shelfwear .

Hardcover. Etat : Near Fine. Etat de la jaquette : Very Good. 2nd ptg. Near fine in very good dust jacket. Signed. Name on front free endpaper/ cloth corners and spine ends lightly rubbed/ dust jacket faded at edges, some chipping and rubs. Signed.

Hard Cover. Etat : Fine. Etat de la jaquette : Fine-. 215 pages. "This design-oriented book is the derivative of a series of lectures recently given by the author and sponsored by the Professional Development Seminars of the Assocation for Computing Machinery. The text includes a discussion of the funational requirements of automated information systems and how they relate to file structures, query processors, directory generation, and searching and updating. It thoroughly establishes formulations of estimating memory requirements and access and update speeds." FINE HARDCOVER, previous owner's note present on front blank endpaper, else no underlining or other wear. FINE- DUST JACKET. Size: 8vo - over 7¾" - 9¾" tall.

Comb. Etat : Near Fine. First Edition. First Edition. Variously paginated. 10 7/8 x 8 3/8 inches. Publisher's white printed wrappers with cut out window to view title. Comb bound. Soiling to the wrappers, internally clean. This example with number '00066' stamped on title page. Reproduced typescript printed on recto only. Comb. Moore School Report No: 64-03, prepared for the Office of Naval Research, Information Sciences Branch, under Contract Nonr 551(40). "Library classification systems in general use today today arrange the descriptors or terms, used to catalog the books, into a hierarchy of relations. At the bottom of the hierarchy more terms can be added and new subdivisions created but the structure above the lowest level remains fixed unless the entire tree of relations is to be reconstructed. The hierarchical assignments are made by professional indexers on the basis of current technology and the presently known relationships among the various spheres of human knowledge. A system is here suggested that would make use of a digital computer in order to constantly revise the classification of the descriptors in terms of their actual usage within the document descriptions themselves.A computer algorithm is defind which accomplishes this partitioning and a program was written and run on the IBM 7090." (abstract) "The research that has culminated in the publication of this paper was initiated in response to a specific problem posed by Dr. Noah S. Prywes, Associate Professor of the Moore School of Electrical Engineering. In early 1961 a complete conception of a Multi-List Information Processing System was being formulated (later in the year to be published as a technical report on project Multilist), and a gap existed in the system between the point where a description (being a set of descriptors) was converted to a number to be decoded by a tree to an associative memory address and the point where this tree could accept it as input. The most promising solution suggested was one which assigned temporary code numbers to the descriptors and allowed 'renaming' of these codes in order to maintain a desired consistency between the two above mentioned points of the system. In the ensuing two years a solution along these lines was found and demonstrated on the IBM 7090 computer, but it was soon recognized that this process of renaming, which produced a so-called exclusive partitioning of a descriptor vocabulary, was of itself a potentially useful, aside from its role int he above mentioned Multilist Information Processing System." (preface) The Moore School was home of the famous Moore School Lectures and was a major research computing hub at the this time - a natural partner to work with. Rare, with only a few entries in Worldcat. PROVENANCE: From the library of Artificial Intelligence Pioneer Ray Solomonoff (unmarked).