A Novel Algorithm for Generating GVKEY-CIK Link Table

This paper presents a do-it-yourself algorithm to generate the historical GVKEY-CIK link table. The proposed algorithm features to pre-classify sample data into different treatment subgroups and utilizes historical firm information available from the source data to increase (reduce) matching efficiency (errors). Simulation results show that our algorithm is superior to applying only conventional name matching operations over the whole sample: 57.5 percent of the overall matching results are error-free ex-ante, and for the remaining 42.5 percent of data, records without Type I errors (with Type II errors) increase (decrease) by 34.0 percent (59.4 percent) when the optimal threshold is used.

A Symmetry Motivated Link Table

Proper identification of oriented knots and 2-component links requires a precise link nomenclature. Motivated by questions arising in DNA topology, this study aims to produce a nomenclature unambiguous with respect to link symmetries. For knots, this involves distinguishing a knot type from its mirror image. In the case of 2-component links, there are up to sixteen possible symmetry types for each link type. The study revisits the methods previously used to disambiguate chiral knots and extends them to oriented 2-component links with up to nine crossings. Monte Carlo simulations are used to report on writhe, a geometric indicator of chirality. There are ninety-two prime 2-component links with up to nine crossings. Guided by geometrical data, linking number, and the symmetry groups of 2-component links, canonical link diagrams for all but five link types (9 5 2, 9 34 2, 9 35 2, 9 39 2, and 9 41 2) are proposed. We include complete tables for prime knots with up to ten crossings and prime links with up to nine crossings. We also prove a result on the behavior of the writhe under local lattice moves.

A Symmetry Motivated Link Table

Proper identification of oriented knots and 2-component links requires a precise link nomenclature. Motivated by questions arising in DNA topology, this study aims to produce a nomenclature unambiguous with respect to link symmetries. For knots, this involves distinguishing a knot type from its mirror image. In the case of 2-component links, there are up to sixteen possible symmetry types for each topology. The study revisits the methods previously used to disambiguate chiral knots and extends them to oriented 2-component links with up to nine crossings. Monte Carlo simulations are used to report on writhe, a geometric indicator of chirality. There are ninety-two prime 2-component links with up to nine crossings. Guided by geometrical data, linking number and the symmetry groups of 2-component links, a canonical link diagram for each link type is proposed. All diagrams but six were unambiguously chosen ( 8 1 2 5 , 9 5 2 , 9 3 2 4 , 9 3 2 5 , 9 3 2 9 , and 9 4 2 1 ). We include complete tables for prime knots with up to ten crossings and prime links with up to nine crossings. We also prove a result on the behavior of the writhe under local lattice moves.

A New FTL-Based Flash Memory Management Scheme for Flash-Based Storage Systems

In this paper, we propose a novel and efficient flash translation layer scheme called BLTF: Block Link-Table FTL. In this proposed scheme, all blocks can be used for servicing update requests, so updates operation can be performed on any of the physical blocks, through uniting log blocks and physical blocks, it can avoid uneven erasing and low block utilization. The invalid blocks, in BLTF scheme, could be reclaimed properly and intensively, it can avoid merging log blocks with physical blocks. At last, the BLTF is tested by simulation, which demonstrates the BLTF can effectively solve data storage problems. Through comparison with other algorithms, we can know that the proposed BLTF greatly prolongs service life of flash devices and improves efficiency of blocks erasing operation.

A Pattern Matching Algorithm for Double-Type Characters

A fast and efficient matching algorithm is proposed to address the issue on multi-pattern matching of double-byte string, for example Chinese characters, which has major difference with single-byte string matching algorithm. The algorithm capitalizes on double cross link data list and two finite prefix automata to match a double-byte character, so as to solve the storage expansion problems in which the double-byte cross data link table results. The method requires less storage in comparison with double-byte cross data link table, and has the same order of magnitude in efficiency as a single-byte cross-link table approach.