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An O(NP) sequence comparison algorithm

Sun Wu, Udi Manber, Gene Myers, Webb Miller
1990 Information Processing Letters  
We present an algorithm for finding a shortest edit distance of A and B whose worst case running time is O(NP) and whose expected running time is O(N + PD).  ...  A parameter related to D is the number of deletions in such a script, P = D/2 − (N − M)/2.  ...  O(MN log logN/ log N) and O(MN/ log N) for arbitrary and finite alphabet sets respectively.  ... 
doi:10.1016/0020-0190(90)90035-v fatcat:pt6ctvywmnaz5or66fmyrupu7u

Asymmetric k-center is log* n-hard to approximate

Julia Chuzhoy, Sudipto Guha, Eran Halperin, Sanjeev Khanna, Guy Kortsarz, Robert Krauthgamer, Joseph (Seffi) Naor
2005 Journal of the ACM  
We show that the Asymmetric k-Center problem is hard to approximate up to a factor of log * n − Θ(1) unless NP ⊆ DTIME(n log log n ).  ...  Since an O(log * n)-approximation algorithm is known for this problem, this essentially resolves the approximability of this problem.  ...  Acknowledgements We would like to thank Samir Khuller for bringking the metric k-Center with costs to our attention.  ... 
doi:10.1145/1082036.1082038 fatcat:5c7f6xvcpfapzpwdd76lp2zqsm

Asymmetric k-center is log* n-hard to approximate

Julia Chuzhoy, Sudipto Guha, Eran Halperi, Sanjeev Khanna, Guy Kortsarz, Joseph (Seffi) Nao
2004 Proceedings of the thirty-sixth annual ACM symposium on Theory of computing - STOC '04  
We show that the Asymmetric k-Center problem is hard to approximate up to a factor of log * n − Θ(1) unless NP ⊆ DTIME(n log log n ).  ...  Since an O(log * n)-approximation algorithm is known for this problem, this essentially resolves the approximability of this problem.  ...  Acknowledgements We would like to thank Samir Khuller for bringking the metric k-Center with costs to our attention.  ... 
doi:10.1145/1007352.1007363 dblp:conf/stoc/ChuzhoyGHKKN04 fatcat:w5j5zgxmurhhtevaoxcjtfjvju

N-H···O hydrogen bonding: An FT-IR, NIR study of N-methylformamide-ether systems

Branislav Jovic, Aleksandar Nikolic, Erna Davidovic, Slobodan Petrovic
2010 Journal of the Serbian Chemical Society  
The best correlation between the experimentally determined and the calculated pK a values was found for the CSpKa program, ΔpK a (log pK a (exp) -log pK a (cal)) = 0.56.  ...  If 298 log K is correlated with both σ* and E S , Fig 5. Fig. 5 . 5 Plot of I D vs. experimental (ν 0 /Δν) 1/2 for N-methylformamide-electron donors.  ...  The desorption of CO 2 is the rate-determining step: скенирајућом електронском микроскопијом (SEM), дифракцијом X-зрака (XRD) и фотоелектронском спектроскопијом X-зрака (XPS).  ... 
doi:10.2298/jsc1002157j fatcat:ar2vsn6m3fdotj2mu4nfjcktjm

On the Student-t Mixture Inverse Gaussian Modelwith an Application to Protein Production Sobre el modelo gaussiano inverso mezclado t-Student y una aplicaci'{o}n a producci'{o}n de prote'{i}nas

ANTONIO SANHUEZA, VÍCTOR LEIVA, LILIANA LÓPEZ-KLEINE
2011 Revista Colombiana de Estadística  
as an alternative methodology to the procedures available until now.  ...  Moreover, to evaluate the potential influence of atypical observations, we produce a diagnostic analysis for the model.  ...  Acknowledgements The authors wish to thank the editors Leonardo Trujillo, Ph.D. and Piedad Urdinola, Ph.D., and anonymous referees for their constructive comments on an earlier version of this manuscript  ... 
doaj:4dfced0a7750424984fd89b7e566398d fatcat:t7na4vy4bnghbk6kotq45xktqa

Approximating the exponential, the lanczos method and an Õ(m)-time spectral algorithm for balanced separator

Lorenzo Orecchia, Sushant Sachdeva, Nisheeth K. Vishnoi
2012 Proceedings of the 44th symposium on Theory of Computing - STOC '12  
We give a novel spectral approximation algorithm for the balanced (edge-)separator problem that, given a graph G, a constant balance b ∈ (0, 1/2], and a parameter γ, either finds an Ω(b)-balanced cut of  ...  As an application, we obtain a simple and practical algorithm, with output conductance O( √ γ), for balanced separator that runs in timeÕ( m / √ γ).  ...  (log 1 /δ + log(1 + A )) log 1 /δ + (log 1 /δ) 2 , where the tilde hides polynomial factors in log log n and log log 1 /δ.  ... 
doi:10.1145/2213977.2214080 dblp:conf/stoc/OrecchiaSV12 fatcat:pfm4ddapsfdurmbo6gxrhvnfwa

An observational study of dust nucleation in Mira (o Ceti)

T. Kamiński, K. T. Wong, M. R. Schmidt, H. S. P. Müller, C. A. Gottlieb, I. Cherchneff, K. M. Menten, D. Keller, S. Brünken, J. M. Winters, N. A. Patel
2016 Astronomy and Astrophysics  
Aims: Identify and characterize aluminum bearing species in the circumstellar gas of Mira (o Ceti) in order to elucidate their role in the production of Al_2O_3 dust.  ...  at 30 mas; observations with ALMA, APEX, and Herschel in 2013-2015 for studying cycle and inter-cycle variability of the rotational lines of Al bearing molecules; optical records as far back as 1965 to  ...  Kipper (Tartu Observatory) for sending us a copy of his article. We are also grateful to O. Adriyenko (Terskol Observatory) for providing us with his spectra and E.  ... 
doi:10.1051/0004-6361/201628664 fatcat:wby6u6psqfb4fpoeerjhhsjnly

Distributed Exact Weighted All-Pairs Shortest Paths in Õ(n^5/4) Rounds [article]

Chien-Chung Huang, Danupon Nanongkai, Thatchaphol Saranurak
2017 arXiv   pre-print
The problem admits (1+o(1))-approximation Õ(n)-time algorithms LenzenP-podc15,Nanongkai-STOC14, which are matched with Ω̃(n)-time lower bounds Nanongkai-STOC14,LenzenP_stoc13,FrischknechtHW12[Θ̃, Õ and  ...  Our techniques also yield an Õ(n^3/4k^1/2+n)-time algorithm for the k-source shortest paths problem where we want every node to know distances from k sources; this improves Elkin's recent bound Elkin-STOC17  ...  Nanongkai and Saranurak would like to thank Rotem Oshman for comments on the preliminary version of the result.  ... 
arXiv:1708.03903v2 fatcat:6oljfbvonvdwtggwnihimrl3mi

Approximate CVP_p in Time 2^{0.802 n}

Friedrich Eisenbrand, Moritz Venzin, Peter Sanders, Grzegorz Herman, Fabrizio Grandoni
2020 European Symposium on Algorithms  
This matches the currently fastest constant factor approximation algorithm for the shortest vector problem w.r.t. 𝓁₂.  ...  We show that a constant factor approximation of the shortest and closest lattice vector problem w.r.t. any 𝓁_p-norm can be computed in time 2^{(0.802 +ε) n}.  ...  in inequality (2) and simplifying, we find N ( √ nB n 2 , aB n ∞ ) ≤ poly(n) 2 n[H(φ)+ φ 2 log( 2πe φ )] Both H(φ) and φ 2 log( 2πe φ ) decrease to 0 as φ decreases to 0.  ... 
doi:10.4230/lipics.esa.2020.43 dblp:conf/esa/EisenbrandV20 fatcat:jj6xo272fjcebcqojty6omkcpa

Approximate CVP_p in time 2^0.802 n [article]

Friedrich Eisenbrand, Moritz Venzin
2020 arXiv   pre-print
This matches the currently fastest constant factor approximation algorithm for the shortest vector problem w.r.t. ℓ_2.  ...  We show that a constant factor approximation of the shortest and closest lattice vector problem w.r.t. any ℓ_p-norm can be computed in time 2^(0.802 +ϵ) n.  ...  inequality (2) and simplifying, we find N ( nB n 2 , aB n ∞ ) ≤ poly(n) 2 n[H(φ)+ φ 2 log( 2πe φ )] Both H(φ) and φ 2 log( 2πe φ ) decrease to 0 as φ decreases to 0.  ... 
arXiv:2005.04957v2 fatcat:ws4v7nc35baincg5ebgbfix6q4

Approximating the Exponential, the Lanczos Method and an Õ(m)-Time Spectral Algorithm for Balanced Separator [article]

Lorenzo Orecchia, Sushant Sachdeva, Nisheeth K. Vishnoi
2011 arXiv   pre-print
We give a novel spectral approximation algorithm for the balanced separator problem that, given a graph G, a constant balance b \in (0,1/2], and a parameter \gamma, either finds an \Omega(b)-balanced cut  ...  As an application, we obtain a simple and practical algorithm, with output conductance O(\sqrt(\gamma)), for balanced separator that runs in time \tilde{O}(m/\sqrt(\gamma)).  ...  (λ 1 (A) − λ n (A)) · log 1 /δ} · (log 1 /δ) · log log 1 /δ .  ... 
arXiv:1111.1491v1 fatcat:rrr3jlcb25gc3awnyyhavxiuaq

An arithmetic approach for the computing with words paradigm

M. Delgado, O. Duarte, I. Requena
2005 International Journal of Intelligent Systems  
In this article we show an alternative kind of system that remedies those deficits in many applications. It is based on fuzzy arithmetic rather than fuzzy logic. We also show application examples.  ...  Computing with words applications are mostly built using rule-based systems, which have some important deficits: First, it is not easy to deal with high dimension problems because the size of the rule  ...  Acknowledgments Special thanks to Mónica Alvarado and Efraín Chiguasuque for allowing us to include the results of their degree work 13 in Section 6.1.  ... 
doi:10.1002/int.20123 fatcat:mc7iz4pugbhfddfdkydsh5ndpa

Analysis and parallel implementation of a forced N-body problem

C.E. Torres, H. Parishani, O. Ayala, L.F. Rossi, L.-P. Wang
2013 Journal of Computational Physics  
This paper concerns algorithms for solving a specific N-body problem, namely, a system of disturbance velocities for hydrodynamically interacting particles in a particle-laden turbulent flow.  ...  Our complexity analysis showed that for large N-body problems, the proposed GMRes scheme scales well for moderate to large number of processors in current tera to petascale computers.  ...  Acknowledgments This work was made possible by support from the National Science Foundation through grants OCI-0904534 and ATM-0730766 and by the National Center for Atmospheric Research (NCAR).  ... 
doi:10.1016/j.jcp.2013.03.008 fatcat:wtr6gczq65gnhankz4dkwmmfe4

Approximate CVP in time 2^0.802 n – now in any norm! [article]

Thomas Rothvoss, Moritz Venzin
2021 arXiv   pre-print
This contrasts the corresponding 2^n time, (gap)-SETH based lower bounds for these problems that even apply for small constant approximation.  ...  For both problems, SVP and CVP, we reduce to the case of the Euclidean norm.  ...  We can either guess and succeed with probability log(n) − log(n) , or we return log(n) log(n) different convex bodies, one of which verifies the desired properties.  ... 
arXiv:2110.02387v1 fatcat:wbj262rakreqxdal57ibpavak4

A O(1/ε 2) n -Time Sieving Algorithm for Approximate Integer Programming [chapter]

Daniel Dadush
2012 Lecture Notes in Computer Science  
The Integer Programming Problem (IP) for a polytope P ⊆ R n is to find an integer point in P or decide that P is integer free.  ...  We give a randomized algorithm for an approximate version of this problem, which correctly decides whether P contains an integer point or whether a (1 + ) scaling of P around its barycenter is integer  ...  Runtime and Failure Probability: We first analyze the runtime. First, we make O(n log R r ) guesses for the value of Λ(C, L, M ). We run the ShortVectors algorithm once for each such guess β.  ... 
doi:10.1007/978-3-642-29344-3_18 fatcat:w4dotelqqvaodp5lxsqnjp4kqy
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