Presents three text compression methods of increasing power and evaluates each based on the trade-off between compression gain and processing time. The advantages of using hash coding for speed and optimal arithmetic coding to successor information for compression gain are discussed. (26 references) (Author/CLB)

False drops occur in a system of random superimposed coding for edge-notched, punched, and feature cards. Formulae for the false dropping fraction are derived, and figures and tables are given for the calculated values in the most popular scheme. (Author/LS)

Explores the new storage technology of optical data disks and introduces a data structure, the inverted signature tree, for storing data on optical data disks for efficient text searching. The inverted signature tree approach is compared to the use of text signatures and the B+ tree. (22 references) (Author/CLB)

Investigates applicability of inverted file processing in magnetic bubble memories by presenting four magnetic bubble memory models as storage mediums: one based on a major-minor loop configuration; one utilizing a decoder design on a magnetic bubble memory chip; and two based on different structural configurations of the first two. (MBR)

Suggests new method of external distribution called tree partitioning that involves use of binary tree to split incoming file into successively smaller partitions for internal sorting. Number of disc accesses during a tree-partitioning sort were calculated in simulation using files extracted from British National Bibliography catalog files. (19…

Review of office filing facility filing and retrieval mechanisms for unstructured and mixed media information focuses on free text methods. Also discussed are the state of the art in handling voice and image data, problems with searching text surrogates to implement free text content retrieval, and work of Project Minstrel. (Author/MBR)

Introduces the multicharacter trie as an index structure that can improve the time needed for retrieving full-text materials stored on CD-ROMs. The advantages of this structure compared to other structures are described, and experimental results comparing it to the widely used B+ tree and other structures used for full-text retrieval are…

Analyzes computer terminal memory performance in terms of overflow probability and average queueing delay, and presents new method to derive a closed expression for data arrivals with Erlangly distributed interarrival times and an approach to derive steady state probability expressions of the terminal memory content process. Twenty references are…