Date 2426 Oct. 1988
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29th Annual Symposium on Foundations of Computer Science (IEEE Cat. No.88CH26526)
Publication Year: 1988 PDF (251 KB) 
Results on learnability and the VapnikChervonenkis dimension
Publication Year: 1988, Page(s):120  129
Cited by: Papers (3)The problem of learning a concept from examples in a distributionfree model is considered. The notion of dynamic sampling, wherein the number of examples examined can increase with the complexity of the target concept, is introduced. This method is used to establish the learnability of various concept classes with an infinite VapnikChervonenkis (VC) dimension. An important variation on the probl... View full abstract»

On the complexity of kinodynamic planning
Publication Year: 1988, Page(s):306  316
Cited by: Papers (35)The following problem, is considered: given a robot system find a minimaltime trajectory from a start position and velocity to a goal position and velocity, while avoiding obstacles and respecting dynamic constraints on velocity and acceleration. The simplified case of a point mass under Newtonian mechanics together with velocity and acceleration bounds is considered. The point must be flown from... View full abstract»

Constructive results from graph minors: linkless embeddings
Publication Year: 1988, Page(s):398  409
Cited by: Papers (5)A formal study of threedimensional topological graph theory is initiated. The problem of deciding whether a graph can be embedded in 3space so that no collection of vertexdisjoint cycles is topologically linked is considered first. The RobertsonSeymour Theory of Graph Minors is applicable to this problem and guarantees the existence of an O(
n ^{3}) algorithm for the decision p... View full abstract» 
On a theory of computation over the real numbers; NP completeness, recursive functions and universal machines
Publication Year: 1988, Page(s):387  397
Cited by: Papers (8)  Patents (2)A model for computation over an arbitrary (ordered) ring
R is presented. In this general setting, universal machines, partial recursive functions, and NPcomplete problems are obtained. While the theory reflects of classical overZ (e.g. the computable functions are the recursive functions), it also reflects the special mathematical character of the underlying ringR (e.... View full abstract» 
Nonexpressibility of fairness and signaling
Publication Year: 1988, Page(s):377  386
Cited by: Papers (1)Expressiveness results for indeterminate data flow primitives are established. Choice primitives with three differing fairness assumptions are considered, and it is shown that they are strictly inequivalent in expressive power. It is also shown that the ability to announce choices enhances the expressive power of two of the primitives. These results are proved using a very crude semantics and will... View full abstract»

On pointers versus addresses
Publication Year: 1988, Page(s):532  538
Cited by: Papers (1)The problem of determining the cost of randomaccess memory (RAM) is addressed by studying the simulation of random addressing by a machine which lacks it, called a pointer machine. The model allows the use of a data type of choice. A RAM program of time
t and spaces can be simulated inO (t logs ) time using a tree. However, this is not an obvious lowe... View full abstract» 
Polynomial algorithm for the
Publication Year: 1988, Page(s):444  451k cut problem
Cited by: Papers (24)  Patents (2)The
k cut problem is to find a partition of an edge weighted graph intok nonempty components, such that the total edge weight between components is minimum. This problem is NPcomplete for arbitraryk and its version involving fixing a vertex in each component is NP hard even fork =3. A polynomial algorithm for the case of a fixedk is presented View full abstract» 
Optimal parallel algorithm for the Hamiltonian cycle problem on dense graphs
Publication Year: 1988, Page(s):186  193
Cited by: Papers (1)G.A. Dirac's classical theorem (1952) asserts that if every vertex of a graph
G onn vertices has degree at leastn /2, theG has a Hamiltonian cycle. A fast parallel algorithm on a concurrentreadexclusivewrite parallel randomaccess machine (CREW PRAM) is given to find a Hamiltonian cycle in such graphs. The algorithm uses a linear number of processors and i... View full abstract» 
Fully abstract models of the lazy lambda calculus
Publication Year: 1988, Page(s):368  376
Cited by: Papers (2)Much of what is known about the model theory and proof theory of the λcalculus is sensible in nature, i.e. only head normal forms are semantically meaningful. However, most functional languages are lazy, i.e. programs are evaluated in normal order to weak head normal forms. The author develops a theory of lazy or strongly sensible λcalculus that corresponds to practice. A general m... View full abstract»

Homogeneous measures and polynomial time invariants
Publication Year: 1988, Page(s):36  41
Cited by: Papers (3)The usual probability distributions are concentrated on strings that do not differ noticeably in any fundamental characteristics, except their informational size (Kolmogorov complexity). The formalization of this statement is given and shown to distinguish a class of homogeneous probability measures suggesting various applications. In particular, it could explain why the average case NPcompletene... View full abstract»

Dynamic perfect hashing: upper and lower bounds
Publication Year: 1988, Page(s):524  531
Cited by: Papers (9)  Patents (3)A randomized algorithm is given for the dictionary problem with
O (1) worstcase time for lookup andO (1) amortized expected time for insertion and deletion. An Ω(logn ) lower bound is proved for the amortized worstcase time complexity of any deterministic algorithm in a class of algorithms encompassing realistic hashingbased schemes. If the worstcase lookup time... View full abstract» 
Combinatorial algorithms for the generalized circulation problem
Publication Year: 1988, Page(s):432  443
Cited by: Papers (4)  Patents (1)A generalization of the maximumflow problem is considered in which the amounts of flow entering and leaving an arc are linearly related. More precisely, if
x (e ) units of flow enter an arce ,x (e )λ(e ) units arrive at the other end. For instance, nodes of the graph can correspond to different currencies, with the multipliers being the exc... View full abstract» 
Fully dynamic techniques for point location and transitive closure in planar structures
Publication Year: 1988, Page(s):558  567
Cited by: Papers (3)It is shown that a planar
st graphG admits two total orders on the setV ∪E ∪F , whereV ,E , andF are, respectively, the sets of vertices, edges and faces ofG , with V =n . An O(n ) space data structure for the maintenance of the two orders is exhibited that supports an update of ... View full abstract» 
Increasing the size of a network by a constant factor can increase performance by more than a constant factor
Publication Year: 1988, Page(s):221  230
Cited by: Papers (17)In one routing scheme which has been implemented on a parallel architecture based on the butterfly graph, messages are sometimes destroyed. It is shown that if messages are sent to random destinations, the expected number of messages that reach their destinations is Θ(
n (logn )1/q ), wheren is the size of the butterfly graph andq is the number of... View full abstract» 
A lower bound for matrix multiplication
Publication Year: 1988, Page(s):64  67It is proved that computing the product of two
n ×n matrices over the binary field requires at least 2.5n ^{2}O(n ^{2}) multiplications View full abstract» 
An optimal algorithm for intersecting line segments in the plane
Publication Year: 1988, Page(s):590  600
Cited by: Papers (19)The authors present the first optimal algorithm for the following problem: given
n line segments in the plane, compute allk pairwise intersections in O(n logn +k ) time. Within the same asymptotic cost the algorithm will also compute the adjacencies of the planar subdivision induced by the segments, which is a useful data structure for contourfilling ... View full abstract» 
Sublineartime parallel algorithms for matching and related problems
Publication Year: 1988, Page(s):174  185
Cited by: Papers (11)The authors present the first sublineartime deterministic parallel algorithms for bipartite matching and several related problems, including maximal nodedisjoint paths, depthfirst search, and flows in zeroone networks. The results are based on a better understanding of the combinatorial structure of the above problems, which lead to new algorithmic techniques. In particular, it is shown how t... View full abstract»

Reachability is harder for directed than for undirected finite graphs
Publication Year: 1988, Page(s):358  367
Cited by: Papers (12)It is shown that for directed graphs, reachability can not be expressed by an existential monadic secondorder sentence. The proof makes use of EhrenfeuchtFraisse games, along with probabilistic. However, it is shown that for directed graphs with degree at most
k , reachability is expressible by an existential monadic secondorder sentence. One reason for the interest in the main result ... View full abstract» 
Zeroknowledge with logspace verifiers
Publication Year: 1988, Page(s):25  35
Cited by: Papers (5)Interactive proof systems are considered in which the best set of possible verifiers is restricted to the class of probabilistic logspace automata. A. Condon (1988) introduced this model and showed that if the protocols are allowed to run for arbitrarily many rounds, exponentialtime languages can be proved to a logspace verifier. To better approximate the usual notion of interactive proof syste... View full abstract»

Three stacks
Publication Year: 1988, Page(s):514  523
Cited by: Papers (1)The storage allocation for three stacks has been traditionally accomplished by using pointers to store the stacks as linked lists or by relocating the stacks within memory when collisions take place. The former approach requires additional space to store the pointers, and the latter approach requires additional time. The authors explore the extent to which some additional space or time is required... View full abstract»

An approximate maxflow mincut theorem for uniform multicommodity flow problems with applications to approximation algorithms
Publication Year: 1988, Page(s):422  431
Cited by: Papers (72)  Patents (4)A multicommodity flow problem is considered where for each pair of vertices (
u ,v ) it is required to sendf halfunits of commodity (u ,v ) fromu tov andf halfunits of commodity (v ,u ) fromv tou without violating capacity constraints. The main result is an algorithm for performing the t... View full abstract» 
New upper bounds in Klee's measure problem
Publication Year: 1988, Page(s):550  556
Cited by: Papers (12)New upper bounds are given for the measure problem of V. Klee (1977) that significantly improve the previous bounds for dimensions greater than 2. An O(
n ^{d/2} logn ,n ) timespace upper bound to compute the measure of a set ofn boxes in Euclideand space is obtained. The solution requires several novel ideas including application of the inclus... View full abstract» 
Genus
Publication Year: 1988, Page(s):458  468g graphs have pagenumber O(√g )A book embedding of a graph consists of a linear ordering of the vertices along the spine of a book and an assignment of edges to pages so that edges on the same page do not intersect. The minimum number of pages in which a graph can be embedded is its pagenumber. The following results are presented: (1) any graph of genus
g has pagenumber O(√g ); and (2) mostn ver... View full abstract» 
Dynamic networks are as fast as static networks
Publication Year: 1988, Page(s):206  219
Cited by: Papers (12)An efficient simulation is given to show that dynamic networks are as fast as static ones up to a constant multiplicative factor. That is, any task can be performed in a dynamic asynchronous network essentially as fast as in a static synchronous network. The simulation protocol is based on an approach in which locality is perceived as the key to fast adaptation to changes in network topology. The ... View full abstract»