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chem-ph/9508004
Bond Orientational Order, Molecular Motion and Free Energy of High Density DNA Mesophases
By equilibrating condensed DNA arrays against reservoirs of known osmotic stress and examining them with several structural probes, it has been possible to achieve a detailed thermodynamic and structural characterization of the change between two distinct regions on the liquid crystalline phase digram: a higher-density...
1995-08-25
2009-10-28
[ "chem-ph", "physics.chem-ph" ]
R. Podgornik, H.H. Strey, K. Gawrisch, D.C. Rau, A. Rupprecht and V.A. Parsegian (National Institutes of Health, Bethesda, MD and Stockholm University, Sweden)
chem-ph/9508003
Coherent Control of Isotope Separation in HD+ Photodissociation by Strong Fields
The photodissociation of the HD+ molecular ion in intense short- pulsed linearly polarized laser fields is studied using a time- dependent wave-packet approach where molecular rotation is fully included. We show that applying a coherent superposition of the fundamental radiation with its second harmonic can lead to asy...
1995-08-22
2019-04-04
[ "chem-ph", "physics.chem-ph" ]
Eric Charron, Annick Giusti-Suzor and Frederick Mies
chem-ph/9508002
Electrostatic potential of a homogeneously charged square and cube in two and three dimensions
A closed form of the electrostatic potential of a homogeneously charged cube is derived by integration. The exact result is compared with multipole expansions for the exterior and interior of the cube. The electrostatic potential of a homogeneously charged square in two-dimensional electrostatics is also determined.
1995-08-11
2008-02-03
[ "chem-ph", "physics.chem-ph" ]
Gerhard Hummer (Los Alamos National Laboratory)
chem-ph/9508001
A generalized local approximation to the exchange potential
A new method to obtain a local parameterization for the exchange term in the many--body electronic problem is presented. The approach amounts to the introduction of a coordinate dependent electron effective mass. Numerical results for metallic clusters in the jellium model are compared with other standard methods.
1995-08-02
2009-10-28
[ "chem-ph", "mtrl-th", "physics.chem-ph" ]
Aurel Bulgac, Caio Lewenkopf and Vadim Mickrjukov
chem-ph/9507005
Bifurcation in Rotational Spectra of Nonlinear AB$_2$ Molecules
A classical microscopic theory of rovibrational motion at high angular momenta in symmetrical non-linear molecules AB$_2$ is derived within the framework of small oscillations near the stationary states of a rotating molecule. The full-dimensional analysis including stretching vibrations has confirmed the existence of ...
1995-07-26
2009-10-28
[ "chem-ph", "physics.chem-ph" ]
I.N. Kozin and I.M. Pavlichenkov
chem-ph/9507004
The hydration free energy of water
We study the chemical potential of water as a function of charge based on perturbation theory. By calculating the electrostatic-energy fluctuations of two states (fully charged and uncharged) we are able to determine accurate values for the dependence of the chemical potential on charge. We find identical results for t...
1995-07-20
2008-02-03
[ "chem-ph", "physics.chem-ph" ]
Gerhard Hummer, Lawrence R. Pratt, and Angel E. Garcia (LANL)
chem-ph/9507003
Kinetic and thermodynamic analysis of proteinlike heteropolymers: Monte Carlo histogram technique
Using Monte Carlo dynamics and the Monte Carlo Histogram Method, the simple three-dimensional 27 monomer lattice copolymer is examined in depth. The thermodynamic properties of various sequences are examined contrasting the behavior of good and poor folding sequences. The good (fast folding) sequences have sharp well-d...
1995-07-07
2009-10-28
[ "chem-ph", "cond-mat", "physics.chem-ph" ]
Nicholas D. Socci and Jos\'e Nelson Onuchic (Department of Physics, UCSD)
chem-ph/9507002
Spectrum Generating Algebra for X$_{3}$ Molecules
A new spectrum generating algebra for a unified description of rotations and vibrations in polyatomic molecules is introduced. An application to nonlinear X$_3$ molecules shows that this model (i) incorporates exactly the relevant point group, (ii) provides a complete classification of oblate top states, and (iii) trea...
1995-07-06
2009-10-28
[ "chem-ph", "nucl-th", "physics.chem-ph" ]
R. Bijker, A.E.L. Dieperink and A. Leviatan
chem-ph/9507001
The Markoff-Automaton - a New Algorithm for Simulating the Time--Evolution of Large Stochastic Dynamic Systems
We describe a new algorithm for simulating complex Markoff-processes. We have used a reaction-cell method in order to simulate arbitrary reactions. It can be used for any kind of RDS on arbitrary topologies, including fractal dimensions or configurations not being related to any spatial geometry. The events within a si...
1995-07-05
2009-10-28
[ "chem-ph", "cond-mat", "hep-lat", "mtrl-th", "physics.chem-ph" ]
Thomas Fricke, Dietmar Wendt
chem-ph/9506004
Titrating Polyelectrolytes - Variational Calculations and Monte Carlo Simulations
Variational methods are used to calculate structural and thermodynamical properties of a titrating polyelectrolyte in a discrete representation. The Coulomb interactions are emulated by harmonic repulsive forces, the force constants being used as variational parameters to minimize the free energy. For the titrating cha...
1995-06-15
2008-02-03
[ "chem-ph", "cond-mat", "hep-lat", "physics.chem-ph" ]
B. J\"onsson, M. Ullner (Phys. Chemistry 2, Lund U.), C. Peterson, O. Sommelius and B. S\"oderberg (Theor. Phys. 2, Lund U.)
chem-ph/9506001
Quantum Confinement Effects in Semiconductor Clusters II
The band gaps and spectral shifts of CdS, CdSe, CdTe, AlP, GaP, GaAs, and InP semiconductor clusters are calculated from band structure calculations using accurate local and non-local empirical pseudopotentials. The effect of spin-orbit coupling on the band structures is included in the calculations when they are impor...
1995-06-03
2009-10-28
[ "chem-ph", "cond-mat", "physics.chem-ph" ]
Antonietta Tomasulo and Mushti V. Ramakrishna
chem-ph/9506003
Growth Pattern of Silicon Clusters
Tight-binding molecular dynamics simulated annealing technique is employed to search for the ground state geometries of silicon clusters containing 11-17 atoms. These studies revealed that layer formation is the dominant growth pattern in all these clusters. Fullerene-like precursor structures consisting of fused penta...
1995-06-03
2009-10-28
[ "chem-ph", "cond-mat", "physics.chem-ph" ]
Atul Bahel, Jun Pan, and Mushti V. Ramakrishna
chem-ph/9506002
Chemistry of Nanoscale Semiconductor Clusters
The ground state structures of small silicon clusters are determined through exhaustive tight-binding molecular dynamics simulation studies. These simulations revealed that \Si{11} is an icosahedron with one missing cap, \Si{12} is a complete icosahedron, \Si{13} is a surface capped icosahedron, \Si{14} is a 4-4-4 laye...
1995-06-03
2016-08-31
[ "chem-ph", "cond-mat", "physics.chem-ph" ]
Jun Pan, Atul Bahel, and Mushti V. Ramakrishna
chem-ph/9505006
Thermodynamics of helix-coil transitions studied by multicanonical algorithms
Thermodynamics of helix-coil transitions in amino-acid homo-oligomers are studied by the recently proposed multicanonical algorithms. Homo-oligomers of length 10 are considered for three characteristic amino acids, alanine (helix former), valine (helix indifferent), and glycine (helix breaker). For alanine other length...
1995-05-25
2008-02-03
[ "chem-ph", "cond-mat", "hep-lat", "physics.chem-ph" ]
Yuko Okamoto and Ulrich H.E. Hansmann
chem-ph/9505004
Sequence Dependence in an Off-Lattice Model for Protein Folding
See chem-ph/9505003.
1995-05-24
2008-02-03
[ "chem-ph", "physics.chem-ph" ]
Anders Irb\"ack and Frank Potthast
chem-ph/9505002
Global geometry optimization of clusters using a growth strategy optimized by a genetic algorithm
A new strategy for global geometry optimization of clusters is presented. Important features are a restriction of search space to favorable nearest-neighbor distance ranges, a suitable cluster growth representation with diminished correlations, and easy transferability of the results to larger clusters. The strengths a...
1995-05-24
2009-10-28
[ "chem-ph", "physics.chem-ph" ]
Bernd Hartke (Department of Theoretical Chemistry, University of Stuttgart, Germany)
chem-ph/9505003
Studies of an Off-Lattice Model for Protein Folding: Sequence Dependence and Improved Sampling at Finite Temperature
We study the thermodynamic behavior of a simple off-lattice model for protein folding. The model is two-dimensional and has two different ``amino acids''. Using numerical simulations of all chains containing eight or ten monomers, we examine the sequence dependence at a fixed temperature. It is shown that only a few of...
1995-05-24
2009-10-28
[ "chem-ph", "physics.chem-ph" ]
Anders Irb\"ack and Frank Potthast
chem-ph/9505005
On the free energy of ionic hydration
The hydration free energies of ions exhibit an approximately quadratic dependence on the ionic charge, as predicted by the Born model. We analyze this behavior using second-order perturbation theory. This provides effective methods to calculating free energies from equilibrium computer simulations. The average and the ...
1995-05-24
2008-02-03
[ "chem-ph", "physics.chem-ph" ]
Gerhard Hummer, Lawrence R. Pratt, and Angel E. Garcia
chem-ph/9505001
On finite-size effects in computer simulations using the Ewald potential
We discuss the origin and relevance for computer simulations of a strong finite-size effect that appears when using the Ewald summation formula. It can be understood as arising from a volume-dependent shift of the potential in a finite, periodic box relative to the infinite volume limit. This shift is due to the fact t...
1995-05-04
2009-10-28
[ "chem-ph", "physics.chem-ph" ]
Francisco Figueirido, Gabriela S. Del Buono and Ronald M. Levy, (Department of Chemistry, Wright-Rieman Laboratories, Rutgers)
chem-ph/9504004
Density functional theory using an optimized exchange-correlation potential
We have performed self-consistent calculations for first and second row atoms using a variant of density-functional theory, the optimized effective potential method, with an approximation due to Krieger, Li and Iafrate and a correlation-energy functional developed by Colle and Salvetti. The mean absolute deviation of f...
1995-04-27
2009-10-28
[ "chem-ph", "physics.chem-ph" ]
Tobias Grabo and E.K.U. Gross
chem-ph/9504003
Application of A Distributed Nucleus Approximation In Grid Based Minimization of the Kohn-Sham Energy Functional
In the distributed nucleus approximation we represent the singular nucleus as smeared over a smallportion of a Cartesian grid. Delocalizing the nucleus allows us to solve the Poisson equation for theoverall electrostatic potential using a linear scaling multigrid algorithm.This work is done in the context of minimizing...
1995-04-24
2009-10-28
[ "chem-ph", "physics.chem-ph" ]
Karthik A. Iyer, Michael P. Merrick, and Thomas L. Beck
chem-ph/9504002
Metal-Insulator Transition in C60-Polymers
Variations in the band structures of C60-polymers are studied, when pi-conjugation conditions are changed. We look at band structures in order to discuss a metal-insulator transition, using a semi-empirical model with the Su-Schrieffer-Heeger type electron-phonon interactions. We find that electronic structures change ...
1995-04-14
2008-02-03
[ "chem-ph", "cond-mat", "mtrl-th", "physics.chem-ph" ]
Kikuo Harigaya
chem-ph/9504001
Temperature Dependence of the Optical Response of Small Sodium Clusters
We present an analysis of the temperature dependence of the optical response of small sodium clusters in a temperature range bracketing the melting phase transition. When the temperature increases, the mean excitation energy undergoes a red shift and the plasmon is significantly broadened, in agreement with recent expe...
1995-04-11
2009-10-28
[ "chem-ph", "physics.chem-ph" ]
Aurel Bulgac and Caio Lewenkopf (University of Washington)
chem-ph/9502010
Nonlinearity and trapping in excitation transfer: Dimers and Trimers.
We study the interplay between nonlinearity in exciton transport and trapping due to a sink site for the dimer and the trimer with chain configuration by a numerical integration of the discrete nonlinear Schroedinger equation. Our results for the dimer show, that the formation of a self trapped state due to the nonline...
1995-02-25
2016-08-31
[ "chem-ph", "physics.chem-ph" ]
Ivan Barvik (Institute of Physics, Charles University, Prague), Bernd Esser, Holger Schanz (Institut fuer Physik, Humboldt Universitaet, Berlin)
chem-ph/9502011
Excitonic - vibronic coupled dimers: A dynamic approach
The dynamical properties of exciton transfer coupled to polarization vibrations in a two site system are investigated in detail. A fixed point analysis of the full system of Bloch - oscillator equations representing the coupled excitonic - vibronic flow is performed. For overcritical polarization a bifurcation converti...
1995-02-25
2016-08-31
[ "chem-ph", "physics.chem-ph" ]
Bernd Esser, Holger Schanz (Institut fuer Physik, Humboldt Universitaet, Berlin)
chem-ph/9502009
A Monte Carlo study of temperature-programmed desorption spectra with attractive lateral interactions
We present results of a Monte Carlo study of temperature-programmed desorption in a model system with attractive lateral interactions. It is shown that even for weak interactions there are large shifts of the peak maximum temperatures with initial coverage. The system has a transition temperature below which the desorp...
1995-02-20
2009-10-28
[ "chem-ph", "cond-mat", "physics.chem-ph" ]
A.P.J. Jansen (Laboratory of Inorganic Chemistry and Catalysis, Eindhoven University of Technology, The Netherlands)
chem-ph/9502007
A Variational Approach for Minimizing Lennard-Jones Energies
A variational method for computing conformational properties of molecules with Lennard-Jones potentials for the monomer-monomer interactions is presented. The approach is tailored to deal with angular degrees of freedom, {\it rotors}, and consists in the iterative solution of a set of deterministic equations with annea...
1995-02-17
2016-08-31
[ "chem-ph", "hep-lat", "physics.chem-ph" ]
Carsten Peterson, Ola Sommelius and Bo S\"oderberg
chem-ph/9502008
Application of Gradient-Corrected Density Functional Theory to the Structures and Thermochemistries of $\mbox{ScF}_3$, $\mbox{TiF}_4$, $\mbox{VF}_5$, and $\mbox{CrF}_6$
Density functional theory(DFT) and Hartree-Fock(HF) calculations are reported for the family of transition metal fluorides $\mbox{ScF}_3$, $\mbox{TiF}_4$, $\mbox{VF}_5$, and $\mbox{CrF}_6$. Both HF and the local-density-aproximation (LDA) yield excellent agreement with experimental bond lengths, while the B-LYP gradien...
1995-02-17
2016-08-31
[ "chem-ph", "physics.chem-ph" ]
Thomas V. Russo, Richard L. Martin, and P. Jeffrey Hay (Theoretical Division, MS B268, Los Alamos National Laboratory, Los Alamos, NM 87545)
chem-ph/9502006
Sequence Dependence of Self-Interacting Random Chains
We study the thermodynamic behavior of the random chain model proposed by Iori, Marinari and Parisi, and how this depends on the actual sequence of interactions along the chain. The properties of randomly chosen sequences are compared to those of designed ones, obtained through a simulated annealing procedure in sequen...
1995-02-17
2016-08-31
[ "chem-ph", "hep-lat", "physics.chem-ph" ]
Anders Irback and Holm Schwarze
chem-ph/9502005
Critical Behavior of the Widom-Rowlinson Lattice Model
We report extensive Monte Carlo simulations of the Widom-Rowlinson lattice model in two and three dimensions. Our results yield precise values for the critical activities and densities, and clearly place the critical behavior in the Ising universality class.
1995-02-13
2016-08-31
[ "chem-ph", "cond-mat", "physics.chem-ph" ]
Ronald Dickman (Lehman College, City University of New York), and George Stell (State University of New York at Stony Brook)
chem-ph/9502004
"The numerical accuracy of truncated Ewald sums for periodic systems with long-range Coulomb interactions"
Ewald summation is widely used to calculate electrostatic interactions in computer simulations of condensed-matter systems. We present an analysis of the errors arising from truncating the infinite real- and Fourier-space lattice sums in the Ewald formulation. We derive an optimal choice for the Fourier-space cutoff gi...
1995-02-10
2016-08-31
[ "chem-ph", "physics.chem-ph" ]
Gerhard Hummer (Los Alamos National Laboratory, Los Alamos, NM 87545)
chem-ph/9502001
Structure of Si12 Cluster
Tight-binding molecular dynamic simulations have revealed that Si$_{12}$ is an icosahedron with all atoms on the surface of an approximately 5 \AA~ diameter sphere. This is the most spherical cage structure for silicon clusters in the 2-13 atom size range.
1995-02-08
2016-08-31
[ "chem-ph", "cond-mat", "physics.chem-ph" ]
Atul Bahel and Mushti V. Ramakrishna
chem-ph/9502003
Spectral Shifts of Semiconductor Clusters
The shifts of the electronic absorption spectra of GaAs and GaP semiconductor clusters are calculated using accurate pseudopotentials. In the absence of experimental data at present, these calculations provide estimates of expected spectral shifts in these clusters. In addition, these calculations show that Coulomb int...
1995-02-08
2016-08-31
[ "chem-ph", "cond-mat", "physics.chem-ph" ]
Antonietta Tomasulo and Mushti V. Ramakrishnai
chem-ph/9502002
Structure of Silicon Clusters
We determined the structures of silicon clusters in the 11-14 atom size range using the tight-binding molecular dynamics method. These calculations reveal that \Si{11} is an icosahedron with one missing cap, \Si{12} is a complete icosahedron, \Si{13} is a surface capped icosahedron, and \Si{14} is a 4-4-4 layer structu...
1995-02-08
2016-08-31
[ "chem-ph", "cond-mat", "physics.chem-ph" ]
Jun Pan, Atul Bahel, and Mushti V. Ramakrishna
chem-ph/9501002
Integral equation theory for the electrode-electrolyte interface with the central force water model. Results for an aqueous solution of sodium chloride
The structure of an aqueous solution of sodium chloride at a planar electrode is investigated by integral equation techniques. With the central force water model the aqueous electrolyte is modelled as a mixture of sodium and chloride ions and partially charged hydrogen and oxygen atoms interacting via effective spheric...
1995-01-23
2009-10-28
[ "chem-ph", "physics.chem-ph" ]
M. Vossen, F. Forstmann (Institut f\"ur Theoretische Physik, Freie Universit\"at Berlin, Arnimallee 14, 14195 Berlin, Germany)
chem-ph/9501001
Two-Color Coherent Photodissociation of Nitrogen Oxide in Intense Laser Fields
A simple one-dimensional semi-classical model with a Morse potential is used to investigate the possibility of two-color infrared multi-photon dissociation of vibrationally excited nitrogen oxide. The amplitude ratio effects and adiabatic effects are investigated. Some initial states are found to have thresholds smalle...
1995-01-05
2009-10-28
[ "chem-ph", "cond-mat", "physics.chem-ph" ]
Juhi-Lian Julian Ting
cmp-lg/9512005
Term Encoding of Typed Feature Structures
This paper presents an approach to Prolog-style term encoding of typed feature structures. The type feature structures to be encoded are constrained by appropriateness conditions as in Carpenter's ALE system. But unlike ALE, we impose a further independently motivated closed-world assumption. This assumption allows us ...
1995-12-22
2008-02-03
[ "cmp-lg", "cs.CL" ]
Dale Gerdemann
cmp-lg/9512004
Natural language processing: she needs something old and something new (maybe something borrowed and something blue, too)
Given the present state of work in natural language processing, this address argues first, that advance in both science and applications requires a revival of concern about what language is about, broadly speaking the world; and second, that an attack on the summarising task, which is made ever more important by the gr...
1995-12-21
2008-02-03
[ "cmp-lg", "cs.CL" ]
Karen Sparck Jones (Computer Laboratory, University of Cambridge)
cmp-lg/9512003
Limited Attention and Discourse Structure
This squib examines the role of limited attention in a theory of discourse structure and proposes a model of attentional state that relates current hierarchical theories of discourse structure to empirical evidence about human discourse processing capabilities. First, I present examples that are not predicted by Grosz ...
1995-12-18
2008-02-03
[ "cmp-lg", "cs.CL" ]
Marilyn A. Walker
cmp-lg/9512002
The Unsupervised Acquisition of a Lexicon from Continuous Speech
We present an unsupervised learning algorithm that acquires a natural-language lexicon from raw speech. The algorithm is based on the optimal encoding of symbol sequences in an MDL framework, and uses a hierarchical representation of language that overcomes many of the problems that have stymied previous grammar-induct...
1995-12-13
2008-02-03
[ "cmp-lg", "cs.CL" ]
Carl de Marcken (MIT Artificial Intelligence Laboratory)
cmp-lg/9512001
Analysis of the Arabic Broken Plural and Diminutive
This paper demonstrates how the challenging problem of the Arabic broken plural and diminutive can be handled under a multi-tape two-level model, an extension to two-level morphology.
1995-12-09
2008-02-03
[ "cmp-lg", "cs.CL" ]
George A. Kiraz (University of Cambridge)
cmp-lg/9511005
Chart-driven Connectionist Categorial Parsing of Spoken Korean
While most of the speech and natural language systems which were developed for English and other Indo-European languages neglect the morphological processing and integrate speech and natural language at the word level, for the agglutinative languages such as Korean and Japanese, the morphological processing plays a maj...
1995-11-29
2008-02-03
[ "cmp-lg", "cs.CL" ]
WonIl Lee, Geunbae Lee, Jong-Hyeok Lee (POSTECH, Korea)
cmp-lg/9511007
Using Information Content to Evaluate Semantic Similarity in a Taxonomy
This paper presents a new measure of semantic similarity in an IS-A taxonomy, based on the notion of information content. Experimental evaluation suggests that the measure performs encouragingly well (a correlation of r = 0.79 with a benchmark set of human similarity judgments, with an upper bound of r = 0.90 for human...
1995-11-29
2008-02-03
[ "cmp-lg", "cs.CL" ]
Philip Resnik
cmp-lg/9511006
Disambiguating Noun Groupings with Respect to WordNet Senses
Word groupings useful for language processing tasks are increasingly available, as thesauri appear on-line, and as distributional word clustering techniques improve. However, for many tasks, one is interested in relationships among word {\em senses}, not words. This paper presents a method for automatic sense disambigu...
1995-11-29
2008-02-03
[ "cmp-lg", "cs.CL" ]
Philip Resnik
cmp-lg/9511004
An investigation into the correlation of cue phrases, unfilled pauses and the structuring of spoken discourse
Expectations about the correlation of cue phrases, the duration of unfilled pauses and the structuring of spoken discourse are framed in light of Grosz and Sidner's theory of discourse and are tested for a directions-giving dialogue. The results suggest that cue phrase and discourse structuring tasks may align, and sho...
1995-11-22
2008-02-03
[ "cmp-lg", "cs.CL" ]
Janet Cahn (Massachusetts Institute of Technology)
cmp-lg/9511003
The Effect of Resource Limits and Task Complexity on Collaborative Planning in Dialogue
This paper shows how agents' choice in communicative action can be designed to mitigate the effect of their resource limits in the context of particular features of a collaborative planning task. I first motivate a number of hypotheses about effective language behavior based on a statistical analysis of a corpus of nat...
1995-11-15
2008-02-03
[ "cmp-lg", "cs.CL" ]
Marilyn A. Walker
cmp-lg/9511002
Letting the Cat out of the Bag: Generation for Shake-and-Bake MT
Describes an algorithm for the generation phase of a Shake-and-Bake Machine Translation system. Since the problem is NP-complete, it is unlikely that the algorithm will be efficient in all cases, but for the cases tested it offers an improvement over Whitelock's previously published algorithm. The work was carried out ...
1995-11-13
2008-02-03
[ "cmp-lg", "cs.CL" ]
Chris Brew (Language Technology Group, HCRC, Edinburgh)
cmp-lg/9511001
Countability and Number in Japanese-to-English Machine Translation
This paper presents a heuristic method that uses information in the Japanese text along with knowledge of English countability and number stored in transfer dictionaries to determine the countability and number of English noun phrases. Incorporating this method into the machine translation system ALT-J/E, helped to rai...
1995-11-03
2008-02-03
[ "cmp-lg", "cs.CL" ]
Francis Bond (NTT), Kentaro Ogura (NTT), Satoru Ikehara (NTT)
cmp-lg/9510008
Toward an MT System without Pre-Editing --- Effects of New Methods in ALT-J/E ---
Recently, several types of Japanese-to-English machine translation systems have been developed, but all of them require an initial process of rewriting the original text into easily translatable Japanese. Therefore these systems are unsuitable for translating information that needs to be speedily disseminated. To overc...
1995-10-31
2016-08-31
[ "cmp-lg", "cs.CL" ]
Satoru Ikehara (NTT), Satoshi Shirai (NTT), Akio Yokoo (NTT), Hiromi Nakaiwa (NTT)
cmp-lg/9510007
Automatic Identification of Support Verbs: A Step Towards a Definition of Semantic Weight
Current definitions of notions of lexical density and semantic weight are based on the division of words into closed and open classes, and on intuition. This paper develops a computationally tractable definition of semantic weight, concentrating on what it means for a word to be semantically light; the definition invol...
1995-10-25
2008-02-03
[ "cmp-lg", "cs.CL" ]
Mark Dras (Natural Language Unit, Microsoft Institute, Australia)
cmp-lg/9510006
Incorporating Discourse Aspects in English -- Polish MT: Towards Robust Implementation
The main aim of translation is an accurate transfer of meaning so that the result is not only grammatically and lexically correct but also communicatively adequate. This paper stresses the need for discourse analysis the aim of which is to preserve the communicative meaning in English--Polish machine translation. Unlik...
1995-10-15
2008-02-03
[ "cmp-lg", "cs.CL" ]
Malgorzata E. Stys (University of Cambridge), Stefan S. Zemke (Linkoping University)
cmp-lg/9510005
Developing and Evaluating a Probabilistic LR Parser of Part-of-Speech and Punctuation Labels
We describe an approach to robust domain-independent syntactic parsing of unrestricted naturally-occurring (English) input. The technique involves parsing sequences of part-of-speech and punctuation labels using a unification-based grammar coupled with a probabilistic LR parser. We describe the coverage of several corp...
1995-10-09
2008-02-03
[ "cmp-lg", "cs.CL" ]
Ted Briscoe (Cambridge University), and John Carroll (Cambridge University)
cmp-lg/9510003
A Proposal for Word Sense Disambiguation using Conceptual Distance
This paper presents a method for the resolution of lexical ambiguity and its automatic evaluation over the Brown Corpus. The method relies on the use of the wide-coverage noun taxonomy of WordNet and the notion of conceptual distance among concepts, captured by a Conceptual Density formula developed for this purpose. T...
1995-10-04
2008-02-03
[ "cmp-lg", "cs.CL" ]
Eneko Agirre (Euskal Herriko Unibertsitatea), German Rigau (Universitat Politecnica de Catalunya)
cmp-lg/9510004
Disambiguating bilingual nominal entries against WordNet
This paper explores the acquisition of conceptual knowledge from bilingual dictionaries (French/English, Spanish/English and English/Spanish) using a pre-existing broad coverage Lexical Knowledge Base (LKB) WordNet. Bilingual nominal entries are disambiguated agains WordNet, therefore linking the bilingual dictionaries...
1995-10-04
2016-08-31
[ "cmp-lg", "cs.CL" ]
German Rigau (Universitat Politecnica de Catalunya), Eneko Agirre (Euskal Herriko Unibertsitatea)
cmp-lg/9510001
POS Tagging Using Relaxation Labelling
Relaxation labelling is an optimization technique used in many fields to solve constraint satisfaction problems. The algorithm finds a combination of values for a set of variables such that satisfies -to the maximum possible degree- a set of given constraints. This paper describes some experiments performed applying it...
1995-10-02
2008-02-03
[ "cmp-lg", "cs.CL" ]
Lluis Padro (Dept LSI, Universitat Politecnica de Catalunya)
cmp-lg/9509005
ParseTalk about Textual Ellipsis
A hybrid methodology for the resolution of text-level ellipsis is presented in this paper. It incorporates conceptual proximity criteria applied to ontologically well-engineered domain knowledge bases and an approach to centering based on functional topic/comment patterns. We state text grammatical predicates for ellip...
1995-09-28
2008-02-03
[ "cmp-lg", "cs.CL" ]
Michael Strube and Udo Hahn (Computational Linguistics Research Group, Freiburg University, Germany)
cmp-lg/9510002
Using Chinese Text Processing Technique for the Processing of Sanskrit Based Indian Languages: Maximum Resource Utilization and Maximum Compatibility
Chinese text processing systems are using Double Byte Coding , while almost all existing Sanskrit Based Indian Languages have been using Single Byte coding for text processing. Through observation, Chinese Information Processing Technique has already achieved great technical development both in east and west. In contra...
1995-09-27
2008-02-03
[ "cmp-lg", "cs.CL" ]
Md Maruf Hasan (Dept. of Information System & Computer Science National University of Singapore)
cmp-lg/9509004
The Development and Migration of Concepts from Donor to Borrower Disciplines: Sublanguage Term Use in Hard & Soft Sciences
Academic disciplines, often divided into hard and soft sciences, may be understood as "donor disciplines" if they produce more concepts than they borrow from other disciplines, or "borrower disciplines" if they import more than they originate. Terms used to describe these concepts can be used to distinguish between har...
1995-09-13
2008-02-03
[ "cmp-lg", "cs.CL" ]
Robert M. Losee (SILS, U. of North Carolina, Chapel Hill)
cmp-lg/9509003
Cluster Expansions and Iterative Scaling for Maximum Entropy Language Models
The maximum entropy method has recently been successfully introduced to a variety of natural language applications. In each of these applications, however, the power of the maximum entropy method is achieved at the cost of a considerable increase in computational requirements. In this paper we present a technique, clos...
1995-09-09
2008-02-03
[ "cmp-lg", "cs.CL" ]
John D. Lafferty and Bernhard Suhm (Carnegie Mellon)
cmp-lg/9509002
Conserving Fuel in Statistical Language Learning: Predicting Data Requirements
In this paper I address the practical concern of predicting how much training data is sufficient for a statistical language learning system. First, I briefly review earlier results and show how these can be combined to bound the expected accuracy of a mode-based learner as a function of the volume of training data. I t...
1995-09-07
2008-02-03
[ "cmp-lg", "cs.CL" ]
Mark Lauer (Microsoft Institute, Sydney)
cmp-lg/9509001
How much is enough?: Data requirements for statistical NLP
In this paper I explore a number of issues in the analysis of data requirements for statistical NLP systems. A preliminary framework for viewing such systems is proposed and a sample of existing works are compared within this framework. The first steps toward a theory of data requirements are made by establishing some ...
1995-09-07
2008-02-03
[ "cmp-lg", "cs.CL" ]
Mark Lauer (Microsoft Institute, Sydney)
cmp-lg/9508012
A Natural Law of Succession
Consider the problem of multinomial estimation. You are given an alphabet of k distinct symbols and are told that the i-th symbol occurred exactly n_i times in the past. On the basis of this information alone, you must now estimate the conditional probability that the next symbol will be i. In this report, we present a...
1995-08-30
2008-02-03
[ "cmp-lg", "cs.CL" ]
Eric Sven Ristad (Princeton University)
cmp-lg/9508011
The Use of Knowledge Preconditions in Language Processing
If an agent does not possess the knowledge needed to perform an action, it may privately plan to obtain the required information on its own, or it may involve another agent in the planning process by engaging it in a dialogue. In this paper, we show how the requirements of knowledge preconditions can be used to account...
1995-08-29
2008-02-03
[ "cmp-lg", "cs.CL" ]
Karen E. Lochbaum (U S WEST Advanced Technologies)
cmp-lg/9508010
Heuristics and Parse Ranking
There are currently two philosophies for building grammars and parsers -- Statistically induced grammars and Wide-coverage grammars. One way to combine the strengths of both approaches is to have a wide-coverage grammar with a heuristic component which is domain independent but whose contribution is tuned to particular...
1995-08-28
2008-02-03
[ "cmp-lg", "cs.CL" ]
B. Srinivas, Christine Doran and Seth Kulick, (University of Pennsylvania)
cmp-lg/9508009
A Labelled Analytic Theorem Proving Environment for Categorial Grammar
We present a system for the investigation of computational properties of categorial grammar parsing based on a labelled analytic tableaux theorem prover. This proof method allows us to take a modular approach, in which the basic grammar can be kept constant, while a range of categorial calculi can be captured by assign...
1995-08-15
2008-02-03
[ "cmp-lg", "cs.CL" ]
Saturnino F. Luz-Filho and Patrick Sturt (Centre for Cognitive Science, University of Edinburgh)
cmp-lg/9508008
On Constraint-Based Lambek Calculi
We explore the consequences of layering a Lambek proof system over an arbitrary (constraint) logic. A simple model-theoretic semantics for our hybrid language is provided for which a particularly simple combination of Lambek's and the proof system of the base logic is complete. Furthermore the proof system for the unde...
1995-08-15
2008-02-03
[ "cmp-lg", "cs.CL" ]
Jochen Doerre and Suresh Manandhar
cmp-lg/9508007
A Dynamic Approach to Rhythm in Language: Toward a Temporal Phonology
It is proposed that the theory of dynamical systems offers appropriate tools to model many phonological aspects of both speech production and perception. A dynamic account of speech rhythm is shown to be useful for description of both Japanese mora timing and English timing in a phrase repetition task. This orientation...
1995-08-13
2008-02-03
[ "cmp-lg", "cs.CL" ]
Robert Port, Fred Cummins, Michael Gasser (Indiana University)
cmp-lg/9508006
Bi-Lexical Rules for Multi-Lexeme Translation in Lexicalist MT
The paper presents a prototype lexicalist Machine Translation system (based on the so-called `Shake-and-Bake' approach of Whitelock (1992) consisting of an analysis component, a dynamic bilingual lexicon, and a generation component, and shows how it is applied to a range of MT problems. Multi-Lexeme translations are ha...
1995-08-12
2008-02-03
[ "cmp-lg", "cs.CL" ]
Arturo Trujillo (SCMS, The Robert Gordon University, Aberdeen)
cmp-lg/9508005
A Matching Technique in Example-Based Machine Translation
This paper addresses an important problem in Example-Based Machine Translation (EBMT), namely how to measure similarity between a sentence fragment and a set of stored examples. A new method is proposed that measures similarity according to both surface structure and content. A second contribution is the use of cluster...
1995-08-10
2008-02-03
[ "cmp-lg", "cs.CL" ]
Lambros Cranias, Harris Papageorgiou, Stelios Piperidis (Institute for Language and Speech Processing, Greece)
cmp-lg/9508003
A Robust Parsing Algorithm For Link Grammars
In this paper we present a robust parsing algorithm based on the link grammar formalism for parsing natural languages. Our algorithm is a natural extension of the original dynamic programming recognition algorithm which recursively counts the number of linkages between two words in the input sentence. The modified algo...
1995-08-02
2008-02-03
[ "cmp-lg", "cs.CL" ]
Dennis Grinberg, John Lafferty, Daniel Sleator (Carnegie Mellon)
cmp-lg/9508002
A Compositional Treatment of Polysemous Arguments in Categorial Grammar
We discuss an extension of the standard logical rules (functional application and abstraction) in Categorial Grammar (CG), in order to deal with some specific cases of polysemy. We borrow from Generative Lexicon theory which proposes the mechanism of {\em coercion}, next to a rich nominal lexical semantic structure cal...
1995-08-02
2016-08-31
[ "cmp-lg", "cs.CL" ]
Anne-Marie Mineur (University of the Saarland, Germany) and Paul Buitelaar (Brandeis University, USA)
cmp-lg/9508004
Parsing English with a Link Grammar
We develop a formal grammatical system called a link grammar, show how English grammar can be encoded in such a system, and give algorithms for efficiently parsing with a link grammar. Although the expressive power of link grammars is equivalent to that of context free grammars, encoding natural language grammars appea...
1995-08-02
2008-02-03
[ "cmp-lg", "cs.CL" ]
Daniel D. K.Sleator (Carnegie Mellon) and Davy Temperley (Columbia University)
cmp-lg/9508001
Bridging as Coercive Accommodation
In this paper we discuss the notion of "bridging" in Discourse Representation Theory as a tool to account for discourse referents that have only been established implicitly, through the lexical semantics of other referents. In doing so, we use ideas from Generative Lexicon theory, to introduce antecedents for anaphoric...
1995-08-02
2008-02-03
[ "cmp-lg", "cs.CL" ]
Johan Bos (University of the Saarland, Germany), Paul Buitelaar (Brandeis University, USA) and Anne-Marie Mineur (University of the Saarland, Germany)
cmp-lg/9507014
Co-Indexing Labelled DRSs to Represent and Reason with Ambiguities
The paper addresses the problem of representing ambiguities in a way that allows for monotonic disambiguation and for direct deductive computation. The paper focuses on an extension of the formalism of underspecified DRSs to ambiguities introduced by plural NPs. It deals with the collective/distributive distinction, an...
1995-07-25
2008-02-03
[ "cmp-lg", "cs.CL" ]
Uwe Reyle (Institute for Computational Linguistics, University of Stuttgart)
cmp-lg/9507011
Generalizing Case Frames Using a Thesaurus and the MDL Principle
We address the problem of automatically acquiring case-frame patterns from large corpus data. In particular, we view this problem as the problem of estimating a (conditional) distribution over a partition of words, and propose a new generalization method based on the MDL (Minimum Description Length) principle. In order...
1995-07-24
2008-02-03
[ "cmp-lg", "cs.CL" ]
Hang Li, Naoki Abe (C&C Res. Labs.,NEC)
cmp-lg/9507013
Indexed Languages and Unification Grammars
Indexed languages are interesting in computational linguistics because they are the least class of languages in the Chomsky hierarchy that has not been shown not to be adequate to describe the string set of natural language sentences. We here define a class of unification grammars that exactly describe the class of ind...
1995-07-24
2008-02-03
[ "cmp-lg", "cs.CL" ]
Tore Burheim (University of Bergen)
cmp-lg/9507010
On-line Learning of Binary Lexical Relations Using Two-dimensional Weighted Majority Algorithms
We consider the problem of learning a certain type of lexical semantic knowledge that can be expressed as a binary relation between words, such as the so-called sub-categorization of verbs (a verb-noun relation) and the compound noun phrase relation (a noun-noun relation). Specifically, we view this problem as an on-li...
1995-07-24
2008-02-03
[ "cmp-lg", "cs.CL" ]
Naoki Abe, Hang Li, Atsuyoshi Nakamura (Theory NEC Lab., RWCP)
cmp-lg/9507012
A Grammar Formalism and Cross-Serial Dependencies
First we define a unification grammar formalism called the Tree Homomorphic Feature Structure Grammar. It is based on Lexical Functional Grammar (LFG), but has a strong restriction on the syntax of the equations. We then show that this grammar formalism defines a full abstract family of languages, and that it is capabl...
1995-07-24
2008-02-03
[ "cmp-lg", "cs.CL" ]
Tore Burheim (University of Bergen)
cmp-lg/9507008
A Constraint-based Case Frame Lexicon Architecture
In Turkish, (and possibly in many other languages) verbs often convey several meanings (some totally unrelated) when they are used with subjects, objects, oblique objects, adverbial adjuncts, with certain lexical, morphological, and semantic features, and co-occurrence restrictions. In addition to the usual sense varia...
1995-07-21
2016-08-31
[ "cmp-lg", "cs.CL" ]
Kemal Oflazer and Okan Yilmaz (Department of Computer Engineering and Information Science, Bilkent University, Ankara Turkey)
cmp-lg/9507007
An Efficient Algorithm for Surface Generation
A method is given that "inverts" a logic grammar and displays it from the point of view of the logical form, rather than from that of the word string. LR-compiling techniques are used to allow a recursive-descent generation algorithm to perform "functor merging" much in the same way as an LR parser performs prefix merg...
1995-07-21
2016-08-31
[ "cmp-lg", "cs.CL" ]
Christer Samuelsson (University of the Saarland)
cmp-lg/9507009
Specifying Logic Programs in Controlled Natural Language
Writing specifications for computer programs is not easy since one has to take into account the disparate conceptual worlds of the application domain and of software development. To bridge this conceptual gap we propose controlled natural language as a declarative and application-specific specification language. Contro...
1995-07-21
2008-02-03
[ "cmp-lg", "cs.CL" ]
Norbert E. Fuchs, Rolf Schwitter (Department of Computer Science, University of Zurich)
cmp-lg/9507006
Transfer in a Connectionist Model of the Acquisition of Morphology
The morphological systems of natural languages are replete with examples of the same devices used for multiple purposes: (1) the same type of morphological process (for example, suffixation for both noun case and verb tense) and (2) identical morphemes (for example, the same suffix for English noun plural and possessiv...
1995-07-20
2008-02-03
[ "cmp-lg", "cs.CL" ]
Michael Gasser (Indiana University)
cmp-lg/9507005
Comparative Ellipsis and Variable Binding
In this paper, we discuss the question whether phrasal comparatives should be given a direct interpretation, or require an analysis as elliptic constructions, and answer it with Yes and No. The most adequate analysis of wide reading attributive (WRA) comparatives seems to be as cases of ellipsis, while a direct (but as...
1995-07-19
2008-02-03
[ "cmp-lg", "cs.CL" ]
Jan Lerner and Manfred Pinkal (University of the Saarland, Dept. of Computational Linguistics)
cmp-lg/9507004
GRAMPAL: A Morphological Processor for Spanish implemented in Prolog
A model for the full treatment of Spanish inflection for verbs, nouns and adjectives is presented. This model is based on feature unification and it relies upon a lexicon of allomorphs both for stems and morphemes. Word forms are built by the concatenation of allomorphs by means of special contextual features. We make ...
1995-07-18
2016-08-15
[ "cmp-lg", "cs.CL" ]
Antonio Moreno (Universidad Aut\'onoma de Madrid, Madrid, Spain) and Jos\'e M. Go\~ni (Universidad Polit\'ecnica de Madrid, Madrid, Spain)
cmp-lg/9507003
Robust Processing of Natural Language
Previous approaches to robustness in natural language processing usually treat deviant input by relaxing grammatical constraints whenever a successful analysis cannot be provided by ``normal'' means. This schema implies, that error detection always comes prior to error handling, a behaviour which hardly can compete wit...
1995-07-13
2016-08-31
[ "cmp-lg", "cs.CL" ]
Wolfgang Menzel (University of Hamburg)
cmp-lg/9507002
A framework for lexical representation
In this paper we present a unification-based lexical platform designed for highly inflected languages (like Roman ones). A formalism is proposed for encoding a lemma-based lexical source, well suited for linguistic generalizations. From this source, we automatically generate an allomorph indexed dictionary, adequate fo...
1995-07-06
2016-08-15
[ "cmp-lg", "cs.CL" ]
Jos\'e M. Go\~ni, Jos\'e C. Gonz\'alez (E.T.S.I. Telecomunicaci\'on, Universidad Polit\'ecnica de Madrid, Madrid, Spain)
cmp-lg/9507001
Constraint Categorial Grammars
Although unification can be used to implement a weak form of $\beta$-reduction, several linguistic phenomena are better handled by using some form of $\lambda$-calculus. In this paper we present a higher order feature description calculus based on a typed $\lambda$-calculus. We show how the techniques used in \CLG for ...
1995-07-04
2008-02-03
[ "cmp-lg", "cs.CL" ]
Luis Damas, Nelma Moreira
cmp-lg/9506026
A Computational Approach to Aspectual Composition
In this paper, I argue, contrary to the prevailing opinion in the linguistics and philosophy literature, that a sortal approach to aspectual composition can indeed be explanatory. In support of this view, I develop a synthesis of competing proposals by Hinrichs, Krifka and Jackendoff which takes Jackendoff's cross-cutt...
1995-07-01
2008-02-03
[ "cmp-lg", "cs.CL" ]
Michael White (CoGenTex, Inc.)
cmp-lg/9506025
A Categorial Framework for Composition in Multiple Linguistic Domains
This paper describes a computational framework for a grammar architecture in which different linguistic domains such as morphology, syntax, and semantics are treated not as separate components but compositional domains. Word and phrase formation are modeled as uniform processes contributing to the derivation of the sem...
1995-06-29
2008-02-03
[ "cmp-lg", "cs.CL" ]
Cem Bozsahin and Elvan Gocmen (Middle East Technical University)
cmp-lg/9506024
An Approach to Proper Name Tagging for German
This paper presents an incremental method for the tagging of proper names in German newspaper texts. The tagging is performed by the analysis of the syntactic and textual contexts of proper names together with a morphological analysis. The proper names selected by this process supply new contexts which can be used for ...
1995-06-28
2008-02-03
[ "cmp-lg", "cs.CL" ]
Christine Thielen (SfS, University of T"ubingen)
cmp-lg/9506023
Empirical Discovery in Linguistics
A discovery system for detecting correspondences in data is described, based on the familiar induction methods of J. S. Mill. Given a set of observations, the system induces the ``causally'' related facts in these observations. Its application to empirical linguistic discovery is described.
1995-06-26
2008-02-03
[ "cmp-lg", "cs.CL" ]
Vladimir Pericliev (Institute of Mathematics, bl.8, 1113 Sofia, Bulgaria)
cmp-lg/9506022
Deriving Procedural and Warning Instructions from Device and Environment Models
This study is centred on the generation of instructions for household appliances. We show how knowledge about a device, together with knowledge about the environment, can be used for reasoning about instructions. The information communicated by the instructions can be planned from a version of the knowledge of the arti...
1995-06-24
2016-08-31
[ "cmp-lg", "cs.CL" ]
Daniel Ansari (University of Toronto)
cmp-lg/9506021
Prepositional Phrase Attachment through a Backed-Off Model
Recent work has considered corpus-based or statistical approaches to the problem of prepositional phrase attachment ambiguity. Typically, ambiguous verb phrases of the form {v np1 p np2} are resolved through a model which considers values of the four head words (v, n1, p and n2). This paper shows that the problem is an...
1995-06-22
2008-02-03
[ "cmp-lg", "cs.CL" ]
Michael Collins, James Brooks (University of Pennsylvania)
cmp-lg/9506020
GLR-Parsing of Word Lattices Using a Beam Search Method
This paper presents an approach that allows the efficient integration of speech recognition and language understanding using Tomita's generalized LR-parsing algorithm. For this purpose the GLRP-algorithm is revised so that an agenda mechanism can be used to control the flow of computation of the parsing process. This n...
1995-06-22
2008-02-03
[ "cmp-lg", "cs.CL" ]
Steffen Staab (Universitaet Erlangen-Nuernberg, IMMD 8)
cmp-lg/9506019
Review of Charniak's "Statistical Language Learning"
This article is an in-depth review of Eugene Charniak's book, "Statistical Language Learning". The review evaluates the appropriateness of the book as an introductory text for statistical language learning for a variety of audiences. It also includes an extensive bibliography of articles and papers which might be used ...
1995-06-21
2016-08-31
[ "cmp-lg", "cs.CL" ]
David M. Magerman
cmp-lg/9506018
Intelligent Voice Prosthesis: Converting Icons into Natural Language Sentences
The Intelligent Voice Prosthesis is a communication tool which reconstructs the meaning of an ill-structured sequence of icons or symbols, and expresses this meaning into sentences of a Natural Language (French). It has been developed for the use of people who cannot express themselves orally in natural language, and f...
1995-06-21
2008-02-03
[ "cmp-lg", "cs.CL" ]
Pascal Vaillant (Thomson-CSF LCR), Michael Checler (ESIEA / Thomson-CSF LCR)
cmp-lg/9506017
The Effect of Pitch Accenting on Pronoun Referent Resolution
By strictest interpretation, theories of both centering and intonational meaning fail to predict the existence of pitch accented pronominals. Yet they occur felicitously in spoken discourse. To explain this, I emphasize the dual functions served by pitch accents, as markers of both propositional (semantic/pragmatic) an...
1995-06-18
2008-02-03
[ "cmp-lg", "cs.CL" ]
Janet Cahn (Massachusetts Institute of Technology)
cmp-lg/9506016
Indefeasible Semantics and Defeasible Pragmatics
An account of utterance interpretation in discourse needs to face the issue of how the discourse context controls the space of interacting preferences. Assuming a discourse processing architecture that distinguishes the grammar and pragmatics subsystems in terms of monotonic and nonmonotonic inferences, I will discuss ...
1995-06-14
2008-02-03
[ "cmp-lg", "cs.CL" ]
Megumi Kameyama (AI Center and CSLI, SRI International)
cmp-lg/9506015
Ambiguity in the Acquisition of Lexical Information
This paper describes an approach to the automatic identification of lexical information in on-line dictionaries. This approach uses bootstrapping techniques, specifically so that ambiguity in the dictionary text can be treated properly. This approach consists of processing an on-line dictionary multiple times, each tim...
1995-06-14
2008-02-03
[ "cmp-lg", "cs.CL" ]
Lucy Vanderwende
cmp-lg/9506014
Inducing Features of Random Fields
We present a technique for constructing random fields from a set of training samples. The learning paradigm builds increasingly complex fields by allowing potential functions, or features, that are supported by increasingly large subgraphs. Each feature has a weight that is trained by minimizing the Kullback-Leibler di...
1995-06-13
2016-08-31
[ "cmp-lg", "cs.CL" ]
S. Della Pietra, V. Della Pietra (IBM), and J. Lafferty (CMU)