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Optimal shapes of compact strings [article]

Amos Maritan, Cristian Micheletti, Antonio Trovato, Jayanth R. Banavar
2000 arXiv   pre-print
Here we study an analogous problem--that of determining the optimal shapes of closely packed compact strings.  ...  This problem is a mathematical idealization of situations commonly encountered in biology, chemistry and physics, involving the optimal structure of folded polymeric chains.  ...  Figure 2 : 2 Optimal string with local constraint. The string has 65 points with a neighbor separation of unity.  ... 
arXiv:cond-mat/0010210v1 fatcat:tisjirwenve63mqixous2kdmzu

Optimal shapes of compact strings

Amos Maritan, Cristian Micheletti, Antonio Trovato, Jayanth R. Banavar
2000 Nature  
Here we study an analogous problem-that of determining the optimal shapes of closely packed compact strings.  ...  This problem is a mathematical idealization of situations commonly encountered in biology, chemistry and physics, involving the optimal structure of folded polymeric chains.  ...  Figure 2 : 2 Optimal string with local constraint.  ... 
doi:10.1038/35018538 pmid:10917526 fatcat:3wta7gptvfhjxhcnulpwpo5bda

Generic Axiomatization of Families of Noncrossing Graphs in Dependency Parsing

Anssi Yli-Jyrä, Carlos Gómez-Rodríguez
2017 Proceedings of the 55th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)  
These distinctive properties of graph families reduce to forbidden patterns in bracket strings and then compile into regular constraint languages. These are presented in Table 1 .  ...  It is easy to see that the graphs NC-GRAPH are encoded with strings that belong to the Dyck language D 2 generated by the context-free grammar: S → [S]S | {S}S | ε.  ...  The ontology of the search space can be combined with a constraint relaxation strategy, for example, when an out tree is a preferred analysis, but a dag is also possible as an analysis when no tree is  ... 
doi:10.18653/v1/p17-1160 dblp:conf/acl/Yli-JyraG17 fatcat:pabwzjm3tneinb7cd2ga2chbhu

A new type of string field theory

Holger B. Nielsen
2002 AIP Conference Proceedings  
The resulting string field theory is a free theory.  ...  A state with any number of strings get represented by the Cartesian product of two free particle Fock spaces, one for right mover degrees of freedom, and one for left.  ...  to sit in chains (essentially curves with the only half a degree of freedom). 2) In the next step, we impose the constraints so that only "chains" of constituents can actually be created at a time.  ... 
doi:10.1063/1.1454373 fatcat:2brnewnewjcnbmxbzk3n4m6qdy

Unification Grammars and Off-Line Parsability

Efrat Jaeger, Nissim Francez, Shuly Wintner
2005 Journal of Logic, Language and Information  
The context-free backbone can generate a unary branching chain of P 's which immediately leads to infinite ambiguity.  ...  Figure 4 .4 lists the extracted context-free backbone of figure 2.10. The context-free backbone can generate a unary branching chain of P 's which immediately leads to infinite ambiguity.  ... 
doi:10.1007/s10849-005-4511-1 fatcat:zstxzwi4bnhsnfbfeh7uivpf3u

Limits on defects formation and hybrid inflationary models with three-year WMAP observations

Aurélien A Fraisse
2007 Journal of Cosmology and Astroparticle Physics  
corresponding constraints on the D-term strings' mass scale, as well as limits on the F- and D-term coupling constants (κ and λ) and inflationary scales (M and √(ξ)).  ...  Using model selection, we compare the ability of a simple flat power-law LCDM model to describe the data to that of hybrid inflationary models involving global or local cosmic strings, or global textures  ...  Finally, we translate these constraints into bounds on the free parameters of D-and F-term inflationary models.  ... 
doi:10.1088/1475-7516/2007/03/008 fatcat:5azs2n27h5c2bnfyhbodyaq3wm

Generic Axiomatization of Families of Noncrossing Graphs in Dependency Parsing [article]

Anssi Yli-Jyrä, Carlos Gómez-Rodríguez
2017 arXiv   pre-print
unlabeled noncrossing graphs and show how its latent counterpart helps us to represent several families of directed and undirected graphs used in syntactic and semantic parsing of natural language as context-free  ...  These distinctive properties of graph families reduce to forbidden patterns in bracket strings and then compile into regular constraint languages. These are presented in Table 1 .  ...  It is easy to see that the graphs NC-GRAPH are encoded with strings that belong to the Dyck language D 2 generated by the context-free grammar: S → [S]S | {S}S | ε.  ... 
arXiv:1706.03357v1 fatcat:ninq6kzkx5h7xa42vzz5ko3vae

Minimum Energy Path to Membrane Pore Formation and Rupture

Christina L. Ting, Daniel Appelö, Zhen-Gang Wang
2011 Physical Review Letters  
We begin with an arbitrary set of states between two free energy minima. The states are connected on the free energy landscape by a string and relax towards the MEP by an iterative procedure.  ...  As opposed to calculations that require physical insight to impose one or more constraints on the system [17], the string method automatically determines the reaction coordinate of the MEP connecting two  ...  They begin at the free ends and are used to obtain the single-chain statistics for each arm of the amphiphile.  ... 
doi:10.1103/physrevlett.106.168101 pmid:21599415 pmcid:PMC3225126 fatcat:j5j2gaqa2bghleigdxyp722ivq

Local constraints in programming languages part I: syntax

Aravind K. Joshi, Leon S. Levy, Kang Yueh
1980 Theoretical Computer Science  
The method of local constraints attempts to describe context-free languages in an apparently context-sensitive form which helps to retain the intuitive insights about the grammatical structure.  ...  This form of description, while apparently context -sensitive is, in fact, context-free and allows a program derivation structure to be represented as a tree with additional constraints, thus allowing  ...  Y See, e.o,., [93 f or a discussion of non-context-free ,grammars. 4 For further discussion of the chain problem see [5] .  ... 
doi:10.1016/0304-3975(80)90058-4 fatcat:ei6py2hgibdwhngxhx24bd5vmq

Point-like structure in strings and non-commutative geometry

Farhad Ardalan, Amir H. Fatollahi
1997 Physics Letters B  
Dynamics of a free point particle on a multi world-line is presented and shown to reduce to that of a bosonic string theory at the appropriate limit.  ...  Let us now restrict ourselves to the case of open chains and we use following boundary conditions (the same which one put for open strings), x 0 − x 1 = x N − x N +1 = 0; (16) closed chains can be similarly  ...  The supersymmetric string is also easily derivable from a similar noncommutative supersymmetric free particle and will be presented elsewhere.  ... 
doi:10.1016/s0370-2693(97)00807-1 fatcat:6ynyc3zi2vev5lnu7gh5prhgcm

Decision Procedures in Soft, Hard and Bio-ware - Follow Up (Dagstuhl Seminar 11272)

Nikolaj Bjorner, Robert Nieuwenhuis, Helmut Veith, Andrei Voronkov, Marc Herbstritt
2011 Dagstuhl Reports  
The follow-on seminar focused on the remaining objectives, in particular to bio-ware and constraint solving methods.  ...  Hampi constraints express membership in regular languages and bounded context-free languages.  ...  Hampi constraints may contain context-free-language definitions, regular-language definitions and operations, the membership predicate and equations over string terms (word equations).  ... 
doi:10.4230/dagrep.1.7.23 dblp:journals/dagstuhl-reports/BjornerNVV11 fatcat:wfkdnqhh6nbdbf5jgtirejs44u

Page 557 of Mathematical Reviews Vol. 30, Issue 3 [page]

1965 Mathematical Reviews  
The second and third problems considered involve extrapolation of sequences of symbols with inter-symbol constraints and Markov chains, respectively, with the probability of future symbols depending on  ...  The second assumes that the string was created as the result of applying a universal machine to a Markov chain, with the “probability of each symbol being a function of only previous symbols in the finite  ... 

Designing Nucleotide Sequences for Computation: A Survey of Constraints [chapter]

Jennifer Sager, Darko Stefanovic
2006 Lecture Notes in Computer Science  
We define the DNA/RNA Code Constraint problem and cover biochemistry topics relevant to DNA libraries. We examine which biochemical constraints are best suited for DNA word design.  ...  We survey the biochemical constraints useful for the design of DNA code words for DNA computation.  ...  We examine the biomolecular constraints typically used to choose a set of DNA strings suitable for computation.  ... 
doi:10.1007/11753681_22 fatcat:wlu7rmzjinflbak7v4q5vkvpwq

Maximal Singularity-Free Orientation Subregions Associated with Initial Parallel Manipulator Configuration

Luis Garcia, Alexandre Campos
2018 Robotics  
It is generally due to the robot configuration, mainly the platform orientation constraint, the present work intends to find the maximum sphere within the orientation workspace, i.e., the singularity-free  ...  In this algorithm, the geometrical parameters and the direct and inverse singularities are the optimization constraints. The geometrical constraints may be studied using vectorial analysis.  ...  Geometrical Constraint The geometrical constraints occur due to collision between kinematic chains or due to violation of joint limits, which are specific for each joint according to its range of motion  ... 
doi:10.3390/robotics7030057 fatcat:laydpqts3zfmbeiaryfk5grbhq

Lazy stateless incremental evaluation machinery for attribute grammars

Jeroen Bransen, Atze Dijkstra, S. Doaitse Swierstra
2014 Proceedings of the ACM SIGPLAN 2014 Workshop on Partial Evaluation and Program Manipulation - PEPM '14  
We use pretty printing with free variable annotation to explain our techniques.  ...  We evaluate the effectiveness of the overall approach using a simple benchmark for the example, and a more extensive benchmark based on constraint-based type inference implemented with AGs.  ...  For example for constraint based type inference, it is possible to solve all constraints for a closed expression in which no free variables appear.  ... 
doi:10.1145/2543728.2543735 dblp:conf/pepm/BransenDS14 fatcat:6pc3xuvdlrczvjkbxf6jt7ozse
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