EFFICIENT SELF-ADJUSTING HASH TABLE

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for an efficient self-adjusting hash table. An aspect may include hash tables that include hints that describe where objects may be found in the hash table. Additionally or alternatively, an aspect may include, hash flooding of the hash tables by using multiple hash functions. Additionally or alternatively, an aspect may include iterating through elements of a hash table using iteration information that may be stored when a hash table has a low densit

Self-Adjusting Hash Tables for Embedded Flight Applications

A common practice in computer science to associate a value with a key is to use a class of algorithms called a hash-table. These algorithms enable rapid storage and retrieval of values based upon a key. This approach assumes that many keys will need to be stored immediately. A new set of hash-table algorithms optimally uses system resources to ideally represent keys and values in memory such that the information can be stored and retrieved with a minimal amount of time and space. These hash-tables support the efficient addition of new entries. Also, for large data sets, the look-up time for large data-set searches is independent of the number of items stored, i.e., O(1), provided that the chance of collision is low

Design of a multiple bloom filter for distributed navigation routing

Unmanned navigation of vehicles and mobile robots can be greatly simplified by providing environmental intelligence with dispersed wireless sensors. The wireless sensors can work as active landmarks for vehicle localization and routing. However, wireless sensors are often resource scarce and require a resource-saving design. In this paper, a multiple Bloom-filter scheme is proposed to compress a global routing table for a wireless sensor. It is used as a lookup table for routing a vehicle to any destination but requires significantly less memory space and search effort. An error-expectation-based design for a multiple Bloom filter is proposed as an improvement to the conventional false-positive-rate-based design. The new design is shown to provide an equal relative error expectation for all branched paths, which ensures a better network load balance and uses less memory space. The scheme is implemented in a project for wheelchair navigation using wireless camera motes. © 2013 IEEE

The Logarithmic Funnel Heap: A Statistically Self-Similar Priority Queue

The present work contains the design and analysis of a statistically self-similar data structure using linear space and supporting the operations, insert, search, remove, increase-key and decrease-key for a deterministic priority queue in expected O(1) time. Extract-max runs in O(log N) time. The depth of the data structure is at most log* N. On the highest level, each element acts as the entrance of a discrete, log* N-level funnel with a logarithmically decreasing stem diameter, where the stem diameter denotes a metric for the expected number of items maintained on a given level.Comment: 14 pages, 4 figure