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## ‣ Terbium(III) and dysprosium(III) 8-connected 3D networks containing 2,5-thiophenedicarboxylate anion: Crystal structures and photoluminescence studies

Fonte: PERGAMON-ELSEVIER SCIENCE LTD; OXFORD
Publicador: PERGAMON-ELSEVIER SCIENCE LTD; OXFORD

Tipo: Artigo de Revista Científica

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#COORDINATION POLYMER#2,5-THIOPHENEDICARBOXYLIC ACID#LANTHANIDES#LANTHANIDE-ORGANIC FRAMEWORKS#COORDINATION POLYMER#LUMINESCENT PROPERTIES#MAGNETIC-PROPERTIES#SELF-ORGANIZATION#COMPLEXES#TOPOLOGY#PHOSPHOR

Two novel coordination polymers with the formula {[Ln(2)(2,5-tdc)(3)(dmso)(2)].H2O}(n) (Ln = Tb(III) for (1) and Dy(III) for (2)), (2,5-tdc(2-) = 2,5-thiophenedicarboxylate and dmso = dimethylsulfoxide) have been synthesized by the diffusion method and characterized by thermal analysis, vibrational spectroscopy and single crystal X-ray diffraction analysis. Structure analysis reveals that 2,5-tdc(2-) play a versatile role toward different lanthanide ions to form three-dimensional metal-organic frameworks (MOFs) in which the lanthanides ions are heptacoordinated. Photophysical properties were studied using excitation and emission spectra, where the photoluminescence data show the high emission intensity of the characteristic transitions D-5(4 ->) F-7(J) (J= 6, 5, 4 and 3) for (1) and (F9/2 -> HJ)-F-4-H-6 (J = 15/2, 13/2 and 11/2) for (2), indicating that 2,5-tdc(2-) is a good sensitizer. (C) 2012 Elsevier Ltd. All rights reserved.; CNPq; CNPq; CAPES; CAPES; FAPEMIG; FAP-EMIG [CEX-APQ 01565-09]

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## ‣ Purification and characterization of the biological effects of phospholipase A(2) from sea anemone Bunodosoma caissarum

Fonte: Pergamon-Elsevier B.V. Ltd
Publicador: Pergamon-Elsevier B.V. Ltd

Tipo: Artigo de Revista Científica
Formato: 413-420

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Sea anemones contain a variety of biologically active substances. Bunodosoma caissarum is a sea anemone from the Cnidaria phylum, found only in Brazilian coastal waters. The aim of the present work was to study the biological effects of PLA(2) isolated from the sea anemone B. caissarum on the isolated perfused kidney, the arteriolar mesenteric bed and on insulin secretion. Specimens of B. caissarum were collected from the Sao Vicente Channel on the southern coast of the State of São Paulo, Brazil. Reverse phase HPLC analysis of the crude extract of B. caissarum detected three PLA(2) proteins (named BcPLA(2)1, BCPLA(2)2 and BcPLA(2)3) found to be active in B. caissarum extracts. MALDI-TOF mass spectrometry of BcPLA(2)1 showed one main peak at 14.7 kDa. The N-terminal amino acid sequence of BcPLA(2)1 showed high amino acid sequence identity with PLA(2) group III protein isolated from the Mexican lizard (PA23 HELSU, HELSU, PA22 HELSU) and with the honey bee Apis mellifera (PLA(2) and 1POC_A). In addition, BcPLA(2)1 also showed significant overall homology to bee PLA(2). The enzymatic activity induced by native BCPLA(2)1 (20 mu g/well) was reduced by chemical treatment with p-bromophenacyl bromide (p-BPB) and with morin. BcPLA(2)1 strongly induced insulin secretion in presence of high glucose concentration. In isolated kidney...

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## ‣ Terbium(III) and dysprosium(III) 8-connected 3D networks containing 2,5-thiophenedicarboxylate anion: Crystal structures and photoluminescence studies

Fonte: Pergamon-Elsevier B.V. Ltd
Publicador: Pergamon-Elsevier B.V. Ltd

Tipo: Artigo de Revista Científica
Formato: 149-156

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Two novel coordination polymers with the formula {[Ln(2)(2,5-tdc)(3)(dmso)(2)].H2O}(n) (Ln = Tb(III) for (1) and Dy(III) for (2)), (2,5-tdc(2-) = 2,5-thiophenedicarboxylate and dmso = dimethylsulfoxide) have been synthesized by the diffusion method and characterized by thermal analysis, vibrational spectroscopy and single crystal X-ray diffraction analysis. Structure analysis reveals that 2,5-tdc(2-) play a versatile role toward different lanthanide ions to form three-dimensional metal-organic frameworks (MOFs) in which the lanthanides ions are heptacoordinated. Photophysical properties were studied using excitation and emission spectra, where the photoluminescence data show the high emission intensity of the characteristic transitions D-5(4 ->) F-7(J) (J= 6, 5, 4 and 3) for (1) and (F9/2 -> HJ)-F-4-H-6 (J = 15/2, 13/2 and 11/2) for (2), indicating that 2,5-tdc(2-) is a good sensitizer. (C) 2012 Elsevier Ltd. All rights reserved.

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## ‣ Liquid Mixtures Involving Hydrogenated and Fluorinated Chains: (p, ρ, T, x) Surface of (Ethanol + 2,2,2-Trifluoroethanol), Experimental and Simulation

Fonte: American Chemical Society
Publicador: American Chemical Society

Tipo: Artigo de Revista Científica

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The effect of mixing hydrogenated and fluorinated molecules that
simultaneously interact through strong hydrogen bonding was investigated: (ethanol +
2,2,2-trifluoroethanol) binary mixtures were studied both experimentally and by
computer simulation. This mixture displays a very complex behavior when compared
with mixtures of hydrogenated alcohols and mixtures of alkanes and perfluoroalkanes.
The excess volumes are large and positive (unlike those of mixtures of hydrogenated
alchools), while the excess enthalpies are large and negative (contrasting with those of
mixtures of alkanes and perfluoroalkanes). In this work, the liquid density of the
mixtures was measured as a function of composition, at several temperatures from
278.15 to 353.15 K and from atmospheric pressure up to 70 MPa. The corresponding
excess molar volumes, compressibilities, and expansivities were calculated over the
whole (p, ρ, T, x) surface. In order to obtain molecular level insight, the behavior of the mixture was also studied by molecular
dynamics simulation, using the OPLS-AA force field. The combined analysis of the experimental and simulation results indicates
that the peculiar phase behavior of this system stems from a balance between the weak dispersion forces between the
hydrogenated and fluorinated groups and a preferential hydrogen bond between ethanol and 2...

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## ‣ Autoria na Web 2.0 no contexto da educação e a ética dos hackers.

Fonte: In: AMARAL, S. F. do; PRETTO, N. de L. (Org). Ética, Hacker e a Educação. 2. ed. Campinas: Faculdade de Educação/UNICAMP, 2012.
Publicador: In: AMARAL, S. F. do; PRETTO, N. de L. (Org). Ética, Hacker e a Educação. 2. ed. Campinas: Faculdade de Educação/UNICAMP, 2012.

Tipo: Capítulo em livro técnico-científico (ALICE)
Formato: p. 48-61.

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Este artigo discute a importância do exercício da autoria em ambiente virtual da Web 2.0, considerando que se trata de fundamento essencial à aprendizagem, no professor e no aluno. Autoria na Web 2.0 é apresentada como estratégia pedagógica para ambientes de aprendizagem virtuais, que se utilizam principalmente de ferramentas como blog, wiki e redes sociais. Embora não sejam determinantes essas, tecnologias digitais são condicionantes para que a aprendizagem e a autoria ocorram. Autoria na Web 2.0, além do estabelecimento de novos aparatos tecnológicos, requer novos modos de produção, nos quais prevaleça a postura ética dos hackers, favorecendo a participação, a colaboração, a liberdade e o compartilhamento.; 2012; Artigo publicado na revista ETD - Educação Temática Digital, Campinas, SP, v. 12, n. esp., p. 154-173, mar. 2011.

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## ‣ Chaconne, aus der Violin-Sonate no. 4, D moll / Joh. Seb. Bach ; für zwei Violinen übertragen von Friedrich Hermann.; Sonaten und Partiten, violin, BWV 1001-1006. Partita, no. 2. Chaconne; arr.

Fonte: F. Kistner
Publicador: F. Kistner

Tipo: Musical Score

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2 parts ; 34 cm.

Cover title.

For 2 violins.

Cover title.

For 2 violins.

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## ‣ lmmunohistochemical expression of Bcl-2 oncoprotein in EBV-associated nasopharyngeal carcinoma correlated to histological type and survival

Fonte: Murcia : F. Hernández
Publicador: Murcia : F. Hernández

Tipo: Artigo de Revista Científica
Formato: application/pdf

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#Nasopharyngeal carcinoma#Prognosis#CDU::6 - Ciencias aplicadas::61 - Medicina::616 - Patología. Medicina clínica. Oncología::616.2 - Patología del aparato respiratorio

Expression of Bcl-2 is associated with
inhibition of apoptosis and extension of cell survival. In
vitro Bcl-2 protein expression is up-regulated by the
EBV-latency associated antigen latent membrane protein
(LMP-1). We have investigated the relationship between
the presence of EBV-DNA screened by means of
sensitive nested-PCR, nasopharyngeal carcinoma (NPC)
histological types according to two different schemata
(WHO and Micheau classifications) and Bcl-2-124
immunohistochemical expression in 55 biopsy samples
of NPC. EBV genome was detected in 100% of samples
with sufficient DNA quality to support the previous view
that al1 types of NPC are variants of EBV-infected
neoplasia. Bcl-2 was observed in the basa1 layer of
normal nasopharyngeal mucosa and also at cytoplasmic
level in 42 of 55 (76.4%) NPC cases. Mitotic
neoplastic cells usually showed strong cytoplasmic and
chromosomal staining, a finding not well referred to
previously. Bcl-2 expression was significantly associated
(p<0.05) to undifferentiated NPC (UNPC) when a
histological classification with only two major
microscopical types was applied. No close correlations
were found between the presence of EBV-DNA, NPC
location, clinical stage and age or sex of the patients in relation to Bcl-2 positive expression. However...

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## ‣ Minimum Opaque Covers for Polygonal Regions

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 30/10/2012
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The Opaque Cover Problem (OCP), also known as the Beam Detector Problem, is
the problem of finding, for a set S in Euclidean space, the minimum-length set
F which intersects every straight line passing through S. In spite of its
simplicity, the problem remains remarkably intractable. The aim of this paper
is to establish a framework and fundamental results for minimum opaque covers
where S is a polygonal region in two-dimensional space. We begin by giving some
general results about opaque covers, and describe the close connection that the
OCP has with the Point Goalie Problem. We then consider properties of graphical
solutions to the OCP when S is a convex polygonal region in the plane.

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## ‣ Binar Sort: A Linear Generalized Sorting Algorithm

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

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Sorting is a common and ubiquitous activity for computers. It is not
surprising that there exist a plethora of sorting algorithms. For all the
sorting algorithms, it is an accepted performance limit that sorting algorithms
are linearithmic or O(N lg N). The linearithmic lower bound in performance
stems from the fact that the sorting algorithms use the ordering property of
the data. The sorting algorithm uses comparison by the ordering property to
arrange the data elements from an initial permutation into a sorted
permutation.
Linear O(N) sorting algorithms exist, but use a priori knowledge of the data
to use a specific property of the data and thus have greater performance. In
contrast, the linearithmic sorting algorithms are generalized by using a
universal property of data-comparison, but have a linearithmic performance
lower bound. The trade-off in sorting algorithms is generality for performance
by the chosen property used to sort the data elements.
A general-purpose, linear sorting algorithm in the context of the trade-off
of performance for generality at first consideration seems implausible. But,
there is an implicit assumption that only the ordering property is universal.
But, as will be discussed and examined, it is not the only universal property
for data elements. The binar sort is a general-purpose sorting algorithm that
uses this other universal property to sort linearly.; Comment: PDF from Word...

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## ‣ F-Harmonic maps as global maxima

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 05/10/2012
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In this note, we show that some F-harmonic maps into spheres are global
maxima of the variations of their energy functional on the conformal group of
the sphere. Our result extends partially those obtained in [15] and [17] for
harmonic and p-harmonic maps.; Comment: 11

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## ‣ Verification of Ptime Reducibility for system F Terms: Type Inference
in

Dual Light Affine Logic

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

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#Computer Science - Logic in Computer Science#Computer Science - Computational Complexity#F.4.1#F.2.2#D.1.1

In a previous work Baillot and Terui introduced Dual light affine logic
(DLAL) as a variant of Light linear logic suitable for guaranteeing complexity
properties on lambda calculus terms: all typable terms can be evaluated in
polynomial time by beta reduction and all Ptime functions can be represented.
In the present work we address the problem of typing lambda-terms in
second-order DLAL. For that we give a procedure which, starting with a term
typed in system F, determines whether it is typable in DLAL and outputs a
concrete typing if there exists any. We show that our procedure can be run in
time polynomial in the size of the original Church typed system F term.; Comment: 32 pages, 8 figures

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## ‣ On Structural Parameterizations of Hitting Set: Hitting Paths in Graphs Using 2-SAT

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

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Hitting Set is a classic problem in combinatorial optimization. Its input
consists of a set system F over a finite universe U and an integer t; the
question is whether there is a set of t elements that intersects every set in
F. The Hitting Set problem parameterized by the size of the solution is a
well-known W[2]-complete problem in parameterized complexity theory. In this
paper we investigate the complexity of Hitting Set under various structural
parameterizations of the input. Our starting point is the folklore result that
Hitting Set is polynomial-time solvable if there is a tree T on vertex set U
such that the sets in F induce connected subtrees of T. We consider the case
that there is a treelike graph with vertex set U such that the sets in F induce
connected subgraphs; the parameter of the problem is a measure of how treelike
the graph is. Our main positive result is an algorithm that, given a graph G
with cyclomatic number k, a collection P of simple paths in G, and an integer
t, determines in time 2^{5k} (|G| +|P|)^O(1) whether there is a vertex set of
size t that hits all paths in P. It is based on a connection to the 2-SAT
problem in multiple valued logic. For other parameterizations we derive
W[1]-hardness and para-NP-completeness results.; Comment: Presented at the 41st International Workshop on Graph-Theoretic
Concepts in Computer Science...

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## ‣ The Threshold for Random k-SAT is 2^k ln2 - O(k)

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

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#Computer Science - Computational Complexity#Condensed Matter - Statistical Mechanics#Computer Science - Discrete Mathematics#Mathematics - Probability#F.2.2

Let F be a random k-SAT formula on n variables, formed by selecting uniformly
and independently m = rn out of all possible k-clauses. It is well-known that
if r>2^k ln 2, then the formula F is unsatisfiable with probability that tends
to 1 as n tends to infinity. We prove that there exists a sequence t_k = O(k)
such that if r < 2^k ln 2 - t_k, then the formula F is satisfiable with
probability that tends to 1 as n tends to infinity.
Our technique yields an explicit lower bound for the random k-SAT threshold
for every k. For k>3 this improves upon all previously known lower bounds. For
example, when k=10 our lower bound is 704.94 while the upper bound is 708.94.; Comment: Added figures and explained the intuition behind our approach. Made a
correction following comments of Chris Calabro

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## ‣ Abstract Milling with Turn Costs

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 05/12/2009
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#Computer Science - Computational Complexity#Computer Science - Computational Geometry#Computer Science - Data Structures and Algorithms#Computer Science - Logic in Computer Science#F.2.2#G.2.2

The Abstract Milling problem is a natural and quite general graph-theoretic
model for geometric milling problems. Given a graph, one asks for a walk that
covers all its vertices with a minimum number of turns, as specified in the
graph model by a 0/1 turncost function fx at each vertex x giving, for each
ordered pair of edges (e,f) incident at x, the turn cost at x of a walk that
enters the vertex on edge e and departs on edge f. We describe an initial study
of the parameterized complexity of the problem. Our main positive result shows
that Abstract Milling, parameterized by: number of turns, treewidth and maximum
degree, is fixed-parameter tractable, We also show that Abstract Milling
parameterized by (only) the number of turns and the pathwidth, is hard for W[1]
-- one of the few parameterized intractability results for bounded pathwidth.; Comment: 18 pages, 2 figures

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## ‣ Maximum Edge-Disjoint Paths in $k$-sums of Graphs

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 20/03/2013
Português

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#Computer Science - Discrete Mathematics#Computer Science - Data Structures and Algorithms#Mathematics - Combinatorics#05C21, 05C83, 05C85, 68W25#F.2.2#G.2.2

We consider the approximability of the maximum edge-disjoint paths problem
(MEDP) in undirected graphs, and in particular, the integrality gap of the
natural multicommodity flow based relaxation for it. The integrality gap is
known to be $\Omega(\sqrt{n})$ even for planar graphs due to a simple
topological obstruction and a major focus, following earlier work, has been
understanding the gap if some constant congestion is allowed.
In this context, it is natural to ask for which classes of graphs does a
constant-factor constant-congestion property hold. It is easy to deduce that
for given constant bounds on the approximation and congestion, the class of
"nice" graphs is nor-closed. Is the converse true? Does every proper
minor-closed family of graphs exhibit a constant factor, constant congestion
bound relative to the LP relaxation? We conjecture that the answer is yes.
One stumbling block has been that such bounds were not known for bounded
treewidth graphs (or even treewidth 3). In this paper we give a polytime
algorithm which takes a fractional routing solution in a graph of bounded
treewidth and is able to integrally route a constant fraction of the LP
solution's value. Note that we do not incur any edge congestion. Previously
this was not known even for series parallel graphs which have treewidth 2. The
algorithm is based on a more general argument that applies to $k$-sums of
graphs in some graph family...

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## ‣ Mantaining Dynamic Matrices for Fully Dynamic Transitive Closure

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 31/03/2001
Português

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#Computer Science - Data Structures and Algorithms#Computer Science - Discrete Mathematics#F.2.2#G.2.2

In this paper we introduce a general framework for casting fully dynamic
transitive closure into the problem of reevaluating polynomials over matrices.
With this technique, we improve the best known bounds for fully dynamic
transitive closure. In particular, we devise a deterministic algorithm for
general directed graphs that achieves $O(n^2)$ amortized time for updates,
while preserving unit worst-case cost for queries. In case of deletions only,
our algorithm performs updates faster in O(n) amortized time.
Our matrix-based approach yields an algorithm for directed acyclic graphs
that breaks through the $O(n^2)$ barrier on the single-operation complexity of
fully dynamic transitive closure. We can answer queries in $O(n^\epsilon)$ time
and perform updates in $O(n^{\omega(1,\epsilon,1)-\epsilon}+n^{1+\epsilon})$
time, for any $\epsilon\in[0,1]$, where $\omega(1,\epsilon,1)$ is the exponent
of the multiplication of an $n\times n^{\epsilon}$ matrix by an
$n^{\epsilon}\times n$ matrix. The current best bounds on
$\omega(1,\epsilon,1)$ imply an $O(n^{0.58})$ query time and an $O(n^{1.58})$
update time. Our subquadratic algorithm is randomized, and has one-side error.; Comment: 52 pages, 5 figures

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## ‣ Seeded PageRank Solution Paths

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Português

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We study the behavior of network diffusions based on the PageRank random walk
from a set of seed nodes. These diffusions are known to reveal small, localized
clusters (or communities) and also large macro-scale clusters by varying a
parameter that has a dual-interpretation as an accuracy bound and as a
regularization level. We propose a new method that quickly approximates the
result of the diffusion for all values of this parameter. Our method
efficiently generates an approximate $\textit{solution path}$ or
$\textit{regularization path}$ associated with a PageRank diffusion, and it
reveals cluster structures at multiple size-scales between small and large. We
formally prove a runtime bound on this method that is independent of the size
of the network, and we investigate multiple optimizations to our method that
can be more practical in some settings. We demonstrate that these methods
identify refined clustering structure on a number of real-world networks with
up to 2 billion edges.; Comment: 29 pages, 8 figures

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## ‣ The $Tb$-theorem on non-homogeneous spaces that proves a conjecture of Vitushkin

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

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#Mathematics - Analysis of PDEs#Mathematics - Classical Analysis and ODEs#Mathematics - Complex Variables#42B20, 42B37#F.2.2

This article was written in 1999, and was posted as a preprint in CRM
(Barcelona) preprint series $n^0\, 519$ in 2000. However, recently CRM erased
all preprints dated before 2006 from its site, and this paper became
inacessible. It has certain importance though, as the reader shall see.
Formally this paper is a proof of the (qualitative version of the) Vitushkin
conjecture. The last section is concerned with the quantitative version. This
quantitative version turns out to be very important. It allowed Xavier Tolsa to
close the subject concerning Vtushkin's conjectures: namely, using the
quantitative nonhomogeneous $Tb$ theorem proved in the present paper, he proved
the semiadditivity of analytic capacity. Another "theorem", which is implicitly
contained in this paper, is the statement that any non-vanishing $L^2$-function
is accretive in the sense that if one has a finite measure $\mu$ on the complex
plane ${\mathbb C}$ that is Ahlfors at almost every point (i.e. for
$\mu$-almost every $x\in {\mathbb C}$ there exists a constant $M>0$ such that
$\mu(B(x,r))\le Mr$ for every $r>0$) then any one-dimensional antisymmetric
Calder\'on-Zygmund operator $K$ (e.g. a Cauchy integral type operator)
satisfies the following "all-or-nothing" princple: if there exists at least one
function $\phi\in L^2(\mu)$ such that $\phi(x)\ne 0$ for $\mu$-almost every
$x\in {\mathbb C}$ and such that {\it the maximal singular operator}
$K^*\phi\in L^2(\mu)$...

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## ‣ Data Structures for Mergeable Trees

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 11/11/2007
Português

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Motivated by an application in computational topology, we consider a novel
variant of the problem of efficiently maintaining dynamic rooted trees. This
variant requires merging two paths in a single operation. In contrast to the
standard problem, in which only one tree arc changes at a time, a single merge
operation can change many arcs. In spite of this, we develop a data structure
that supports merges on an n-node forest in O(log^2 n) amortized time and all
other standard tree operations in O(log n) time (amortized, worst-case, or
randomized depending on the underlying data structure). For the special case
that occurs in the motivating application, in which arbitrary arc deletions
(cuts) are not allowed, we give a data structure with an O(log n) time bound
per operation. This is asymptotically optimal under certain assumptions. For
the even-more special case in which both cuts and parent queries are
disallowed, we give an alternative O(log n)-time solution that uses standard
dynamic trees as a black box. This solution also applies to the motivating
application. Our methods use previous work on dynamic trees in various ways,
but the analysis of each algorithm requires novel ideas. We also investigate
lower bounds for the problem under various assumptions.

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## ‣ 2-manifold recognition is in logspace

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 02/12/2014
Português

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#Mathematics - Geometric Topology#Computer Science - Computational Complexity#57M99, 68Q15#F.2.2#F.1.3

We prove that the homeomorphism problem for 2-manifolds can be decided in
logspace. The proof relies on Reingold's logspace solution to the undirected
$s,t$-connectivity problem in graphs.; Comment: 11 pages, 2 figures

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