28th Annual Symposium on Foundations of Computer Science (sfcs 1987)最新文献_第2页

Canonical labeling of regular graphs in linear average time 线性平均时间正则图的正则标记

28th Annual Symposium on Foundations of Computer Science (sfcs 1987) Pub Date : 1987-10-12 DOI: 10.1109/SFCS.1987.11

L. Kucera

引用次数: 35

A parallel algorithm for finding a separator in planar graphs 在平面图形中寻找分隔符的并行算法

28th Annual Symposium on Foundations of Computer Science (sfcs 1987) Pub Date : 1987-10-12 DOI: 10.1109/SFCS.1987.3

Hillel Gazit, G. Miller

引用次数: 60

A new algebraic method for robot motion planning and real geometry 机器人运动规划和真实几何的一种新的代数方法

28th Annual Symposium on Foundations of Computer Science (sfcs 1987) Pub Date : 1987-10-12 DOI: 10.1109/SFCS.1987.1

J. Canny

{"title":"A new algebraic method for robot motion planning and real geometry","authors":"J. Canny","doi":"10.1109/SFCS.1987.1","DOIUrl":"https://doi.org/10.1109/SFCS.1987.1","url":null,"abstract":"We present an algorithm which solves the findpath or generalized movers' problem in single exponential sequential time. This is the first algorithm for the problem whose sequential time bound is less than double exponential. In fact, the combinatorial exponent of the algorithm is equal to the number of degrees of freedom, making it worst-case optimal, and equaling or improving the time bounds of many special purpose algorithms. The algorithm accepts a formula for a semi-algebraic set S describing the set of free configurations and produces a one-dimensional skeleton or \"roadmap\" of the set, which is connected within each connected component of S. Additional points may be linked to the roadmap in linear time. Our method draws from results of singularity theory, and in particular makes use of the notion of stratified sets as an efficient alternative to cell decomposition. We introduce an algebraic tool called the multivariate resultant which gives a necessary and sufficient condition for a system of homogeneous polynomials to have a solution, and show that it can be computed in polynomial parallel time. Among the consequences of this result are new methods for quantifier elimination and an improved gap theorem for the absolute value of roots of a system of polynomials.","PeriodicalId":153779,"journal":{"name":"28th Annual Symposium on Foundations of Computer Science (sfcs 1987)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1987-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129681089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 118

The matching problem for bipartite graphs with polynomially bounded permanents is in NC 研究了具有多项式有界永久值的二部图的匹配问题

28th Annual Symposium on Foundations of Computer Science (sfcs 1987) Pub Date : 1987-10-12 DOI: 10.1109/SFCS.1987.56

D. Grigoriev, Marek Karpinski

引用次数: 133

Local management of a global resource in a communication network 通信网络中全球资源的本地管理

28th Annual Symposium on Foundations of Computer Science (sfcs 1987) Pub Date : 1987-10-12 DOI: 10.1145/227595.227596

Y. Afek, B. Awerbuch, Serge A. Plotkin, M. Saks

引用次数: 61

Eigenvalues and graph bisection: An average-case analysis 特征值与图分:一种平均情况分析

28th Annual Symposium on Foundations of Computer Science (sfcs 1987) Pub Date : 1987-10-12 DOI: 10.1109/SFCS.1987.22

R. Boppana

引用次数: 396

Hierarchical memory with block transfer 具有块传输的分层存储器

28th Annual Symposium on Foundations of Computer Science (sfcs 1987) Pub Date : 1987-10-12 DOI: 10.1109/SFCS.1987.31

A. Aggarwal, A. K. Chandra, M. Snir

{"title":"Hierarchical memory with block transfer","authors":"A. Aggarwal, A. K. Chandra, M. Snir","doi":"10.1109/SFCS.1987.31","DOIUrl":"https://doi.org/10.1109/SFCS.1987.31","url":null,"abstract":"In this paper we introduce a model of Hierarchical Memory with Block Transfer (BT for short). It is like a random access machine, except that access to location x takes time f(x), and a block of consecutive locations can be copied from memory to memory, taking one unit of time per element after the initial access time. We first study the model with f(x) = xα for 0 ≪ α ≪ 1. A tight bound of θ(n log log n) is shown for many simple problems: reading each input, dot product, shuffle exchange, and merging two sorted lists. The same bound holds for transposing a √n × √n matrix; we use this to compute an FFT graph in optimal θ(n log n) time. An optimal θ(n log n) sorting algorithm is also shown. Some additional issues considered are: maintaining data structures such as dictionaries, DAG simulation, and connections with PRAMs. Next we study the model f(x) = x. Using techniques similar to those developed for the previous model, we show tight bounds of θ(n log n) for the simple problems mentioned above, and provide a new technique that yields optimal lower bounds of Ω(n log2n) for sorting, computing an FFT graph, and for matrix transposition. We also obtain optimal bounds for the model f(x)= xα with α ≫ 1. Finally, we study the model f(x) = log x and obtain optimal bounds of θ(n log*n) for simple problems mentioned above and of θ(n log n) for sorting, computing an FFT graph, and for some permutations.","PeriodicalId":153779,"journal":{"name":"28th Annual Symposium on Foundations of Computer Science (sfcs 1987)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1987-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129019256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 201

Channel routing of multiterminal nets 多终端网的信道路由

28th Annual Symposium on Foundations of Computer Science (sfcs 1987) Pub Date : 1987-10-12 DOI: 10.1145/179812.179927

Shaodi Gao, M. Kaufmann

引用次数: 45

On the lower envelope of bivariate functions and its applications 二元函数的下包络及其应用

28th Annual Symposium on Foundations of Computer Science (sfcs 1987) Pub Date : 1987-10-12 DOI: 10.1109/SFCS.1987.44

H. Edelsbrunner, J. Pach, J. Schwartz, M. Sharir

{"title":"On the lower envelope of bivariate functions and its applications","authors":"H. Edelsbrunner, J. Pach, J. Schwartz, M. Sharir","doi":"10.1109/SFCS.1987.44","DOIUrl":"https://doi.org/10.1109/SFCS.1987.44","url":null,"abstract":"We consider the problem of obtaining sharp (nearly quadratic) bounds for the combinatorial complexity of the lower envelope (i.e. pointwise minimum) of a collection of n bivariate (or generally multi-variate) continuous and \"simple\" functions, and of designing efficient algorithms for the calculation of this envelope. This problem generalizes the well-studied univariate case (whose analysis is based on the theory of Davenport-Schinzel sequences), but appears to be much more difficult and still largely unsolved. It is a central problem that arises in many areas in computational and combinatorial geometry, and has numerous applications including generalized planar Voronoi diagrams, hidden surface elimination for intersecting surfaces, purely translational motion planning, finding common transversals of polyhedra, and more. In this abstract we provide several partial solutions and generalizations of this problem, and apply them to the problems mentioned above. The most significant of our results is that the lower envelope of n triangles in three dimensions has combinatorial complexity at most O(n2α(n)) (where α(n) is the extremely slowly growing inverse of Ackermann's function), that this bound is tight in the worst case, and that this envelope can be calculated in time O(n2α(n)).","PeriodicalId":153779,"journal":{"name":"28th Annual Symposium on Foundations of Computer Science (sfcs 1987)","volume":"174 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1987-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116132090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

Achievable cases in an asynchronous environment 异步环境中可实现的用例

28th Annual Symposium on Foundations of Computer Science (sfcs 1987) Pub Date : 1987-10-12 DOI: 10.1109/SFCS.1987.5

H. Attiya, A. Bar-Noy, D. Dolev, D. Koller, D. Peleg, R. Reischuk

{"title":"Achievable cases in an asynchronous environment","authors":"H. Attiya, A. Bar-Noy, D. Dolev, D. Koller, D. Peleg, R. Reischuk","doi":"10.1109/SFCS.1987.5","DOIUrl":"https://doi.org/10.1109/SFCS.1987.5","url":null,"abstract":"The paper deals with achievability of fault tolerant goals in a completely asynchronous distributed system. Fischer, Lynch, and Paterson [FLP] proved that in such a system \"nontrivial agreement\" cannot be achieved even in the (possible) presence of a single \"benign\" fault. In contrast, we exhibit two pairs of goals that are achievable even in the presence of up to t ≪ n/2 faulty processors, contradicting the widely held assumption that no nontrivial goals are attainable in such a system. The first pair deals with renaming processors so as to reduce the size of the initial name space. When only uniqueness is required of the new names, we present a lower bound of n + 1 on the size of the new name space, and a renaming algorithm which establishes an upper bound of n + t. In case the new names are required also to preserve the original order, a tight bound of 2t(n- t + 1) - 1 is obtained. The second pair of goals deals with the multi-slot critical section problem. We present algorithms for controlled access to a critical section. As for the number of slots required, a tight bound of t + 1 is proved in case the slots are identical. In the case of distinct slots the upper bound is 2t + 1.","PeriodicalId":153779,"journal":{"name":"28th Annual Symposium on Foundations of Computer Science (sfcs 1987)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1987-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114677886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 87