Oct. 30 1989Nov. 1 1989
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30th Annual Symposium on Foundations of Computer Science (Cat. No.89CH28084)
Publication Year: 1989 PDF (78 KB) 
Conductance and convergence of Markov chainsa combinatorial treatment of expanders
Publication Year: 1989, Page(s):526  531
Cited by: Papers (23)A direct combinatorial argument is given to bound the convergence rate of Markov chains in terms of their conductance (these are statements of the nature `random walks on expanders converge fast'). In addition to showing that the linear algebra in previous arguments for such results on timereversible Markov chains was unnecessary, the direct analysis applies to general irreversible Markov chains View full abstract»

An analogue of the MyhillNerode theorem and its use in computing finitebasis characterizations
Publication Year: 1989, Page(s):520  525
Cited by: Papers (13)A theorem that is a graphtheoretic analog of the MyhillNerode characterization of regular languages is proved. The theorem is used to establish that for many applications obstruction sets are computable by known algorithms. The focus is exclusively on what is computable (by a known algorithm) in principle, as opposed to what is computable in practice View full abstract»

On the computational power of PP and ⊕P
Publication Year: 1989, Page(s):514  519
Cited by: Papers (48)Two complexity classes, PP and ⊕P, are compared with PH (the polynomialtime hierarchy). The main results are as follows: (1) every set in PH is reducible in a certain sense to a set in PP, an (2) every set in PH is reducible to a set in ⊕P under randomized polynomialtime reducibility with twosided bounded error probability. It follows from these results that neither PP nor ⊕P ... View full abstract»

On the network complexity of selection
Publication Year: 1989, Page(s):396  401
Cited by: Papers (9)The sequential complexity of determining the kth largest out of a given set of n keys is known to be linear. Thus, given a pprocessor parallel machine, it is asked whether or not an O(n/p) selection algorithm can be devised for that machine. An Ω((n/p) log log p+log p) lower bound is obtained for selec... View full abstract»

Areaoptimal threelayer channel routing
Publication Year: 1989, Page(s):506  511
Cited by: Papers (3)The channel routing problem in the knockknee mode is considered. The algorithm presented always constructs a correct layout in a channel of bounded size, if there is one, and guarantees that it is wirable with only three conducting layers; that is, the layout is optimal with respect to the area and to the number of layers. The algorithm thus improves all previously known layout algorithms, which ... View full abstract»

A randomized maximumflow algorithm
Publication Year: 1989, Page(s):118  123
Cited by: Papers (2)The authors present a randomized maximumflow algorithm, called the PLED (prudent linking excess diminishing) algorithm, whose expected running time is O(nm+n2(log n )3); this is O(nm) for all except relatively sparse networks. The algorithm is always correct, and in the worst case, which occurs with negligible probability... View full abstract»

Efficient simulations of small shared memories on bounded degree networks
Publication Year: 1989, Page(s):390  395
Cited by: Papers (3)The problem of simulating a parallel randomaccess machine (PRAM) with n processors and memory size m⩾n on an nnode bounded degree network (BDN) is considered. Since many of the more efficient PRAM algorithms use an amount of shared memory not much larger than the number of processors, the case in which m=o(n1+ε) i... View full abstract»

Double precision geometry: a general technique for calculating line and segment intersections using rounded arithmetic
Publication Year: 1989, Page(s):500  505
Cited by: Papers (4)  Patents (3)For the first time it is shown how to reduce the cost of performing specific geometric constructions by using rounded arithmetic instead of exact arithmetic. By exploiting a property of floatingpoint arithmetic called monotonicity, a technique called doubleprecision geometry can replace exact arithmetic with rounded arithmetic in any efficient algorithm for computing the set of intersections of ... View full abstract»

Flow in planar graphs with multiple sources and sinks
Publication Year: 1989, Page(s):112  117
Cited by: Papers (5)  Patents (1)Given a planar network with many sources and sinks, the problem of computing the maximum flow from the sources to the sinks is investigated. An algorithm that runs in O(log2n ) time using O(n1.5) processors on an exclusivereadexclusivewrite parallel randomaccess machine (EREW PRAM) is obtained, when the amount of flow (demand) at each s... View full abstract»

Expanders might be practical: fast algorithms for routing around faults on multibutterflies
Publication Year: 1989, Page(s):384  389
Cited by: Papers (37)  Patents (2)Simple deterministic O(log N)step algorithms for routing packets on a multibutterfly are described. The algorithms are shown to be robust against faults, even in the worst case, and to be efficient from a practical point of view. As a consequence, the multibutterfly is shown to be an excellent candidate for a highbandwidth, lowdiameter switching network underlying a distribute... View full abstract»

Stable maintenance of point set triangulations in two dimensions
Publication Year: 1989, Page(s):494  499
Cited by: Papers (11)Geometric algorithms are explored, assuming that arithmetic is done approximately. Stable algorithms are described for two geometric problems. The first algorithm computes twodimensional convex hulls. The main result is that a triangulation of a set of points in the plane can be maintained stably. The second algorithm deals with line arrangements in the plane View full abstract»

Efficient algorithms for independent assignment on graphic and linear matroids
Publication Year: 1989, Page(s):106  111
Cited by: Papers (4)Efficient algorithms are presented for the matroid intersection problem and generalizations. The algorithm for weighted intersection works by scaling the weights. The cardinality algorithm is a special case that takes advantage of greater structure. Efficiency of the algorithms is illustrated by several implementations. On graphic matroids the algorithms run close to the best bounds for trivial ma... View full abstract»

The synchronization of nonuniform networks of finite automata
Publication Year: 1989, Page(s):376  381The generalized firing squad synchronization problem (GFSSP) is the wellknown firing squad synchronization problem extended to arbitrarily connected networks of finite automata. When the transmission delays associated with the links of a network are allowed to be arbitrary nonnegative integers, the problem is called GFSSPNUD (GFSSP with nonuniform delays). A solution of GFSSPNUD is given for th... View full abstract»

Dynamically computing the maxima of decomposable functions, with applications
Publication Year: 1989, Page(s):488  493
Cited by: Papers (4)The authors present a general technique for updating the maximum (minimum) value of a decomposable function as elements are inserted into and deleted from the set S. Applications of this technique include efficient algorithms for dynamically computing the diameter or closest pair of a set of points, minimum separation among a set of rectangles, smallest distance between a set of points an... View full abstract»

The equivalence and learning of probabilistic automata
Publication Year: 1989, Page(s):268  273
Cited by: Papers (5)It is proved that the equivalence problem for probabilistic automata is solvable in time O((n1+n 2)4), where n1 and n 2 are numbers of states of two given probabilistic automata. This result improves the best previous upper bound of coNP. The algorithm has some interesting applications, for example,... View full abstract»

Solvability in asynchronous environments
Publication Year: 1989, Page(s):422  427
Cited by: Papers (2)The authors present necessary and sufficient combinatorial conditions that determine membership in SMt (respectively, MPt), the class of distributed decision tasks that are solvable in the shared memory (resp. message passing) model by a tresilient randomized protocol, which never errs and works in the presence of a strong adversary. The sufficienc... View full abstract»

Galois groups and factoring polynomials over finite fields
Publication Year: 1989, Page(s):99  104
Cited by: Papers (2)Let p be a prime and F be a polynomial with integer coefficients. Suppose that the discriminant of F is not divisible by p, and denote by m the degree of the splitting field of F over Q and by L the maximal size of the coefficients of F. Then, assuming the generalized Riemann hypothesis (GRH), it is shown that the irr... View full abstract»

A really temporal logic
Publication Year: 1989, Page(s):164  169
Cited by: Papers (48)A realtime temporal logic for the specification of reactive systems is introduced. The novel feature of the logic, TPTL, is the adoption of temporal operators as quantifiers over time variables; every modality binds a variable to the time(s) it refers to. TPTL is demonstrated to be both a natural specification language and a suitable formalism for verification and synthesis. A tableaubased decis... View full abstract»

Upper and lower bounds for routing schemes in dynamic networks
Publication Year: 1989, Page(s):370  375
Cited by: Papers (4)An algorithm and two lower bounds are presented for the problem of constructing and maintaining routing schemes in dynamic networks. The algorithm distributively assigns addresses to nodes and constructs routing tables in a dynamically growing tree. The resulting scheme routes data messages over the shortest path between any source and destination, assigns addresses of O(log2
View full abstract» 
A note on the power of threshold circuits
Publication Year: 1989, Page(s):580  584
Cited by: Papers (37)The author presents a very simple proof of the fact that any language accepted by polynomialsize depthk unboundedfanin circuits of AND and OR gates is accepted by depththree threshold circuits of size n raised to the power O(logk n). The proof uses much of the intuition of S. Toda's result that the polynomial hierarchy is contained in P#P View full abstract»

An upper bound on the number of planar
Publication Year: 1989, Page(s):72  79k sets
Cited by: Papers (4)Given a set S of n points, a subset X of size k is called a kset if there is a hyperplane II that separates X from Xc. It is proved that O(n√k/log*k) is an upper bound for the number of ksets in the plane, thus improving the previous bound of P. Erdos et al. (A ... View full abstract»

Speedingup linear programming using fast matrix multiplication
Publication Year: 1989, Page(s):332  337
Cited by: Papers (26)The author presents an algorithm for solving linear programming problems that requires O((m+n)1.5 nL) arithmetic operations in the worst case, where m is the number of constraints, n the number of variables, and L a parameter defined in the paper. This result improves on the best known time complexity for linear programming ... View full abstract»

On the power of 2way probabilistic finite state automata
Publication Year: 1989, Page(s):480  485
Cited by: Papers (3)The recognition power of twoway probabilistic finitestate automata (2PFAs) is studied. It is shown that any 2PFA recognizing a nonregular language must use exponential expected time infinitely often. The power of interactive proof systems (IPSs) where the verifier is a 2PFA is also investigated. It is shown that (1) IPSs in which the verifier uses private randomization are strictly more powerful... View full abstract»

On the complexity of learning from counterexamples
Publication Year: 1989, Page(s):262  267
Cited by: Papers (12)The complexity of learning concepts belonging to various concrete concept classes C⊆2X over a finite domain X is analyzed in terms of the number of counterexamples that are needed in the worst case. It turns out that for many interesting concept classes there exist exponential differences between the number of counterexamples that are required by a `naive' learni... View full abstract»