1,720,987 research outputs found
Lower bounds for general graph-driven read-once parity branching programs
No full textWe prove the first exponential lower bounds on the size of graph-driven read-once parity branching programs. The functions used are linear codes, permutation matrices and a function that has small unrestricted read-once parity branching programs. Moreover, we characterize all BP1s that are guided by graph orderings. The latter is the case if and only if for each input there is a variable ordering that is compatible with each computation path for the input
Lower bounds for general graph-driven read-once parity branching programs
No full textWe prove the first exponential lower bounds on the size of graph-driven read-once parity branching programs. The functions used are linear codes, permutation matrices and a function that has small unrestricted read-once parity branching programs. Moreover, we characterize all BP1s that are guided by graph orderings. The latter is the case if and only if for each input there is a variable ordering that is compatible with each computation path for the input
Separating ⊕L from L, NL, co-NL and AL (=P) for oblivious turing machines of linear access time
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
In-place heap construction with optimized comparisons, moves, and cache misses
No full textWe show how to build a binary heap in-place in linear time by performing ~ 1.625n element comparisons, at most ~ 2.125n element moves, and ~ n/B cache misses, where n is the size of the input array, B the capacity of the cache line, and ~ f(n) approaches f(n) as n grows. The same bound for element comparisons was derived and conjectured to be optimal by Gonnet and Munro; however, their procedure requires Θ(n) pointers and does not have optimal cache behaviour. Our main idea is to mimic the Gonnet-Munro algorithm by converting a navigation pile into a binary heap. To construct a binary heap in-place, we use this algorithm to build bottom heaps of size and adjust the heap order at the upper levels using Floyd's sift-down procedure. On another frontier, we compare different heap-construction alternatives in practice.</p
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Drawing Planar Graphs on Points Inside a Polygon
No full textIn this paper, we study the problem of drawing a given planar graph such that vertices are at pre-specified points and the entire drawing is inside a given polygon. We give a method that shows that for an -vertex graph and a -sided polygon, bends are always sufficient. We also give an example of a graph where bends is necessary for such a drawing
- …
