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cs/0501052
Stochastic Differential Games in a Non-Markovian Setting
cs.IT cs.CE math.IT
Stochastic differential games are considered in a non-Markovian setting. Typically, in stochastic differential games the modulating process of the diffusion equation describing the state flow is taken to be Markovian. Then Nash equilibria or other types of solution such as Pareto equilibria are constructed using Hami...
cs/0501053
Relational Algebra as non-Distributive Lattice
cs.DB
We reduce the set of classic relational algebra operators to two binary operations: natural join and generalized union. We further demonstrate that this set of operators is relationally complete and honors lattice axioms.
cs/0501054
Arbitrage in Fractal Modulated Markets When the Volatility is Stochastic
cs.IT cs.CE math.IT
In this paper an arbitrage strategy is constructed for the modified Black-Scholes model driven by fractional Brownian motion or by a time changed fractional Brownian motion, when the volatility is stochastic. This latter property allows the heavy tailedness of the log returns of the stock prices to be also accounted ...
cs/0501055
Consistency Problems for Jump-Diffusion Models
cs.IT cs.CE math.IT
In this paper consistency problems for multi-factor jump-diffusion models, where the jump parts follow multivariate point processes are examined. First the gap between jump-diffusion models and generalized Heath-Jarrow-Morton (HJM) models is bridged. By applying the drift condition for a generalized arbitrage-free HJ...
cs/0501056
A Large Deviations Approach to Sensor Scheduling for Detection of Correlated Random Fields
cs.IT math.IT
The problem of scheduling sensor transmissions for the detection of correlated random fields using spatially deployed sensors is considered. Using the large deviations principle, a closed-form expression for the error exponent of the miss probability is given as a function of the sensor spacing and signal-to-noise ra...
cs/0501057
Concavity of the auxiliary function appearing in quantum reliability function an classical-quantum channels
cs.IT math.IT
Concavity of the auxiliary function which appears in the random coding exponent as the lower bound of the quantum reliability function for general quantum states is proven for s between 0 and 1.
cs/0501058
Estimation of the Number of Sources in Unbalanced Arrays via Information Theoretic Criteria
cs.IT math.IT
Estimating the number of sources impinging on an array of sensors is a well known and well investigated problem. A common approach for solving this problem is to use an information theoretic criterion, such as Minimum Description Length (MDL) or the Akaike Information Criterion (AIC). The MDL estimator is known to be...
cs/0501061
Optimal and Suboptimal Finger Selection Algorithms for MMSE Rake Receivers in Impulse Radio Ultra-Wideband Systems
cs.IT math.IT
Convex relaxations of the optimal finger selection algorithm are proposed for a minimum mean square error (MMSE) Rake receiver in an impulse radio ultra-wideband system. First, the optimal finger selection problem is formulated as an integer programming problem with a non-convex objective function. Then, the objectiv...
cs/0501062
On The Tradeoff Between Two Types of Processing Gain
cs.IT math.IT
One of the features characterizing almost every multiple access (MA) communication system is the processing gain. Through the use of spreading sequences, the processing gain of Random CDMA systems (RCDMA), is devoted to both bandwidth expansion and orthogonalization of the signals transmitted by different users. Anot...
cs/0501063
Bandit Problems with Side Observations
cs.IT cs.LG math.IT
An extension of the traditional two-armed bandit problem is considered, in which the decision maker has access to some side information before deciding which arm to pull. At each time t, before making a selection, the decision maker is able to observe a random variable X_t that provides some information on the reward...
cs/0501064
A Non-Cooperative Power Control Game for Multi-Carrier CDMA Systems
cs.IT math.IT
In this work, a non-cooperative power control game for multi-carrier CDMA systems is proposed. In the proposed game, each user needs to decide how much power to transmit over each carrier to maximize its overall utility. The utility function considered here measures the number of reliable bits transmitted per joule o...
cs/0501066
The Noncoherent Rician Fading Channel -- Part I : Structure of the Capacity-Achieving Input
cs.IT math.IT
Transmission of information over a discrete-time memoryless Rician fading channel is considered where neither the receiver nor the transmitter knows the fading coefficients. First the structure of the capacity-achieving input signals is investigated when the input is constrained to have limited peakedness by imposing...
cs/0501067
The Noncoherent Rician Fading Channel -- Part II : Spectral Efficiency in the Low-Power Regime
cs.IT math.IT
Transmission of information over a discrete-time memoryless Rician fading channel is considered where neither the receiver nor the transmitter knows the fading coefficients. The spectral-efficiency/bit-energy tradeoff in the low-power regime is examined when the input has limited peakedness. It is shown that if a fou...
cs/0501068
Learning to automatically detect features for mobile robots using second-order Hidden Markov Models
cs.AI
In this paper, we propose a new method based on Hidden Markov Models to interpret temporal sequences of sensor data from mobile robots to automatically detect features. Hidden Markov Models have been used for a long time in pattern recognition, especially in speech recognition. Their main advantages over other method...
cs/0501071
Capacity Regions and Optimal Power Allocation for Groupwise Multiuser Detection
cs.IT math.IT
In this paper, optimal power allocation and capacity regions are derived for GSIC (groupwise successive interference cancellation) systems operating in multipath fading channels, under imperfect channel estimation conditions. It is shown that the impact of channel estimation errors on the system capacity is two-fold:...
cs/0501072
Inferring knowledge from a large semantic network
cs.AI
In this paper, we present a rich semantic network based on a differential analysis. We then detail implemented measures that take into account common and differential features between words. In a last section, we describe some industrial applications.
cs/0501077
Ontology-Based Users & Requests Clustering in Customer Service Management System
cs.IR cs.CL
Customer Service Management is one of major business activities to better serve company customers through the introduction of reliable processes and procedures. Today this kind of activities is implemented through e-services to directly involve customers into business processes. Traditionally Customer Service Managem...
cs/0501078
Multi-document Biography Summarization
cs.CL
In this paper we describe a biography summarization system using sentence classification and ideas from information retrieval. Although the individual techniques are not new, assembling and applying them to generate multi-document biographies is new. Our system was evaluated in DUC2004. It is among the top performers...
cs/0501079
Data Mining for Actionable Knowledge: A Survey
cs.DB cs.AI
The data mining process consists of a series of steps ranging from data cleaning, data selection and transformation, to pattern evaluation and visualization. One of the central problems in data mining is to make the mined patterns or knowledge actionable. Here, the term actionable refers to the mined patterns suggest...
cs/0501081
A Tree Search Method for Iterative Decoding of Underdetermined Multiuser Systems
cs.IT math.IT
Application of the turbo principle to multiuser decoding results in an exchange of probability distributions between two sets of constraints. Firstly, constraints imposed by the multiple-access channel, and secondly, individual constraints imposed by each users' error control code. A-posteriori probability computatio...
cs/0501082
A Group-Theoretic Approach to the WSSUS Pulse Design Problem
cs.IT math.IT
We consider the pulse design problem in multicarrier transmission where the pulse shapes are adapted to the second order statistics of the WSSUS channel. Even though the problem has been addressed by many authors analytical insights are rather limited. First we show that the problem is equivalent to the pure state ch...
cs/0501084
Towards Automated Integration of Guess and Check Programs in Answer Set Programming: A Meta-Interpreter and Applications
cs.AI
Answer set programming (ASP) with disjunction offers a powerful tool for declaratively representing and solving hard problems. Many NP-complete problems can be encoded in the answer set semantics of logic programs in a very concise and intuitive way, where the encoding reflects the typical "guess and check" nature of...
cs/0501085
Space Frequency Codes from Spherical Codes
cs.IT math.IT
A new design method for high rate, fully diverse ('spherical') space frequency codes for MIMO-OFDM systems is proposed, which works for arbitrary numbers of antennas and subcarriers. The construction exploits a differential geometric connection between spherical codes and space time codes. The former are well studied...
cs/0501086
Clever Search: A WordNet Based Wrapper for Internet Search Engines
cs.AI
This paper presents an approach to enhance search engines with information about word senses available in WordNet. The approach exploits information about the conceptual relations within the lexical-semantic net. In the wrapper for search engines presented, WordNet information is used to specify user's request or to ...
cs/0501088
Information estimations and analysis of structures
cs.IT math.IT
In this paper have written the results of the information analysis of structures. The obtained information estimation (IE) are based on an entropy measure of C. Shannon. Obtained IE is univalent both for the non-isomorphic and for the isomorphic graphs, algorithmically, it is asymptotically steady and has vector char...
cs/0501089
Issues in Exploiting GermaNet as a Resource in Real Applications
cs.AI
This paper reports about experiments with GermaNet as a resource within domain specific document analysis. The main question to be answered is: How is the coverage of GermaNet in a specific domain? We report about results of a field test of GermaNet for analyses of autopsy protocols and present a sketch about the int...
cs/0501090
Stochastic Iterative Decoders
cs.IT math.IT
This paper presents a stochastic algorithm for iterative error control decoding. We show that the stochastic decoding algorithm is an approximation of the sum-product algorithm. When the code's factor graph is a tree, as with trellises, the algorithm approaches maximum a-posteriori decoding. We also demonstrate a sto...
cs/0501091
A complexity-regularized quantization approach to nonlinear dimensionality reduction
cs.IT math.IT
We consider the problem of nonlinear dimensionality reduction: given a training set of high-dimensional data whose ``intrinsic'' low dimension is assumed known, find a feature extraction map to low-dimensional space, a reconstruction map back to high-dimensional space, and a geometric description of the dimension-red...
cs/0501092
Multi-Vehicle Cooperative Control Using Mixed Integer Linear Programming
cs.RO cs.AI cs.MA
We present methods to synthesize cooperative strategies for multi-vehicle control problems using mixed integer linear programming. Complex multi-vehicle control problems are expressed as mixed logical dynamical systems. Optimal strategies for these systems are then solved for using mixed integer linear programming. W...
cs/0501093
Transforming Business Rules Into Natural Language Text
cs.AI
The aim of the project presented in this paper is to design a system for an NLG architecture, which supports the documentation process of eBusiness models. A major task is to enrich the formal description of an eBusiness model with additional information needed in an NLG task.
cs/0501094
Corpus based Enrichment of GermaNet Verb Frames
cs.AI
Lexical semantic resources, like WordNet, are often used in real applications of natural language document processing. For example, we integrated GermaNet in our document suite XDOC of processing of German forensic autopsy protocols. In addition to the hypernymy and synonymy relation, we want to adapt GermaNet's verb...
cs/0501095
Context Related Derivation of Word Senses
cs.AI
Real applications of natural language document processing are very often confronted with domain specific lexical gaps during the analysis of documents of a new domain. This paper describes an approach for the derivation of domain specific concepts for the extension of an existing ontology. As resources we need an ini...
cs/0501096
Transforming and Enriching Documents for the Semantic Web
cs.AI
We suggest to employ techniques from Natural Language Processing (NLP) and Knowledge Representation (KR) to transform existing documents into documents amenable for the Semantic Web. Semantic Web documents have at least part of their semantics and pragmatics marked up explicitly in both a machine processable as well ...
cs/0502001
Some Extensions of Gallager's Method to General Sources and Channels
cs.IT math.IT
The Gallager bound is well known in the area of channel coding. However, most discussions about it mainly focus on its applications to memoryless channels. We show in this paper that the bounds obtained by Gallager's method are very tight even for general sources and channels that are defined in the information-spect...
cs/0502004
Asymptotic Log-loss of Prequential Maximum Likelihood Codes
cs.LG cs.IT math.IT
We analyze the Dawid-Rissanen prequential maximum likelihood codes relative to one-parameter exponential family models M. If data are i.i.d. according to an (essentially) arbitrary P, then the redundancy grows at rate c/2 ln n. We show that c=v1/v2, where v1 is the variance of P, and v2 is the variance of the distrib...
cs/0502006
Neural network ensembles: Evaluation of aggregation algorithms
cs.AI cs.NE
Ensembles of artificial neural networks show improved generalization capabilities that outperform those of single networks. However, for aggregation to be effective, the individual networks must be as accurate and diverse as possible. An important problem is, then, how to tune the aggregate members in order to have a...
cs/0502007
Identification of complex systems in the basis of wavelets
cs.CE cs.NE
In this paper is proposed the method of the identification of complex dynamic systems. Method can be used for the identification of linear and nonlinear complex dynamic systems for the determined or stochastic signals at the inputs and the outputs. It is proposed to use a basis of wavelets for obtaining the impulse t...
cs/0502008
Scientific Data Management in the Coming Decade
cs.DB cs.CE
This is a thought piece on data-intensive science requirements for databases and science centers. It argues that peta-scale datasets will be housed by science centers that provide substantial storage and processing for scientists who access the data via smart notebooks. Next-generation science instruments and simulat...
cs/0502009
Performance Considerations for Gigabyte per Second Transcontinental Disk-to-Disk File Transfers
cs.DB cs.PF
Moving data from CERN to Pasadena at a gigabyte per second using the next generation Internet requires good networking and good disk IO. Ten Gbps Ethernet and OC192 links are in place, so now it is simply a matter of programming. This report describes our preliminary work and measurements in configuring the disk subs...
cs/0502010
TerraServer SAN-Cluster Architecture and Operations Experience
cs.DC cs.DB
Microsoft TerraServer displays aerial, satellite, and to-pographic images of the earth in a SQL database available via the Internet. It is one of the most popular online at-lases, presenting seventeen terabytes of image data from the United States Geological Survey (USGS). Initially de-ployed in 1998, the system demo...
cs/0502011
Where the Rubber Meets the Sky: Bridging the Gap between Databases and Science
cs.DB cs.CE
Scientists in all domains face a data avalanche - both from better instruments and from improved simulations. We believe that computer science tools and computer scientists are in a position to help all the sciences by building tools and developing techniques to manage, analyze, and visualize peta-scale scientific in...
cs/0502015
Can Computer Algebra be Liberated from its Algebraic Yoke ?
cs.SC cs.CE
So far, the scope of computer algebra has been needlessly restricted to exact algebraic methods. Its possible extension to approximate analytical methods is discussed. The entangled roles of functional analysis and symbolic programming, especially the functional and transformational paradigms, are put forward. In the...
cs/0502016
Stability Analysis for Regularized Least Squares Regression
cs.LG
We discuss stability for a class of learning algorithms with respect to noisy labels. The algorithms we consider are for regression, and they involve the minimization of regularized risk functionals, such as L(f) := 1/N sum_i (f(x_i)-y_i)^2+ lambda ||f||_H^2. We shall call the algorithm `stable' if, when y_i is a noi...
cs/0502017
Estimating mutual information and multi--information in large networks
cs.IT cs.AI cs.CV cs.LG math.IT
We address the practical problems of estimating the information relations that characterize large networks. Building on methods developed for analysis of the neural code, we show that reliable estimates of mutual information can be obtained with manageable computational effort. The same methods allow estimation of hi...
cs/0502020
Population Sizing for Genetic Programming Based Upon Decision Making
cs.AI cs.NE
This paper derives a population sizing relationship for genetic programming (GP). Following the population-sizing derivation for genetic algorithms in Goldberg, Deb, and Clark (1992), it considers building block decision making as a key facet. The analysis yields a GP-unique relationship because it has to account for...
cs/0502021
Oiling the Wheels of Change: The Role of Adaptive Automatic Problem Decomposition in Non--Stationary Environments
cs.NE cs.AI
Genetic algorithms (GAs) that solve hard problems quickly, reliably and accurately are called competent GAs. When the fitness landscape of a problem changes overtime, the problem is called non--stationary, dynamic or time--variant problem. This paper investigates the use of competent GAs for optimizing non--stationar...
cs/0502022
Sub-Structural Niching in Non-Stationary Environments
cs.NE cs.AI
Niching enables a genetic algorithm (GA) to maintain diversity in a population. It is particularly useful when the problem has multiple optima where the aim is to find all or as many as possible of these optima. When the fitness landscape of a problem changes overtime, the problem is called non--stationary, dynamic o...
cs/0502023
Sub-structural Niching in Estimation of Distribution Algorithms
cs.NE cs.AI
We propose a sub-structural niching method that fully exploits the problem decomposition capability of linkage-learning methods such as the estimation of distribution algorithms and concentrate on maintaining diversity at the sub-structural level. The proposed method consists of three key components: (1) Problem deco...
cs/0502024
Idempotents, Mattson-Solomon Polynomials and Binary LDPC codes
cs.IT math.IT
We show how to construct an algorithm to search for binary idempotents which may be used to construct binary LDPC codes. The algorithm, which allows control of the key properties of sparseness, code rate and minimum distance, is constructed in the Mattson-Solomon domain. Some of the new codes, found by using this tec...
cs/0502029
Scalability of Genetic Programming and Probabilistic Incremental Program Evolution
cs.NE cs.AI
This paper discusses scalability of standard genetic programming (GP) and the probabilistic incremental program evolution (PIPE). To investigate the need for both effective mixing and linkage learning, two test problems are considered: ORDER problem, which is rather easy for any recombination-based GP, and TRAP or th...
cs/0502033
Pseudo-Codewords of Cycle Codes via Zeta Functions
cs.IT math.IT
Cycle codes are a special case of low-density parity-check (LDPC) codes and as such can be decoded using an iterative message-passing decoding algorithm on the associated Tanner graph. The existence of pseudo-codewords is known to cause the decoding algorithm to fail in certain instances. In this paper, we draw a con...
cs/0502034
Multiobjective hBOA, Clustering, and Scalability
cs.NE cs.AI
This paper describes a scalable algorithm for solving multiobjective decomposable problems by combining the hierarchical Bayesian optimization algorithm (hBOA) with the nondominated sorting genetic algorithm (NSGA-II) and clustering in the objective space. It is first argued that for good scalability, clustering or s...
cs/0502035
Near Maximum-Likelihood Performance of Some New Cyclic Codes Constructed in the Finite-Field Transform Domain
cs.IT math.IT
It is shown that some well-known and some new cyclic codes with orthogonal parity-check equations can be constructed in the finite-field transform domain. It is also shown that, for some binary linear cyclic codes, the performance of the iterative decoder can be improved by substituting some of the dual code codeword...
cs/0502036
Improved Iterative Decoding for Perpendicular Magnetic Recording
cs.IT math.IT
An algorithm of improving the performance of iterative decoding on perpendicular magnetic recording is presented. This algorithm follows on the authors' previous works on the parallel and serial concatenated turbo codes and low-density parity-check codes. The application of this algorithm with signal-to-noise ratio m...
cs/0502037
GF(2^m) Low-Density Parity-Check Codes Derived from Cyclotomic Cosets
cs.IT math.IT
Based on the ideas of cyclotomic cosets, idempotents and Mattson-Solomon polynomials, we present a new method to construct GF(2^m), where m>0 cyclic low-density parity-check codes. The construction method produces the dual code idempotent which is used to define the parity-check matrix of the low-density parity-check...
cs/0502042
Unified Large System Analysis of MMSE and Adaptive Least Squares Receivers for a class of Random Matrix Channels
cs.IT math.IT
We present a unified large system analysis of linear receivers for a class of random matrix channels. The technique unifies the analysis of both the minimum-mean-squared-error (MMSE) receiver and the adaptive least-squares (ALS) receiver, and also uses a common approach for both random i.i.d. and random orthogonal pr...
cs/0502049
Generalised Bent Criteria for Boolean Functions (I)
cs.IT math.IT
Generalisations of the bent property of a boolean function are presented, by proposing spectral analysis with respect to a well-chosen set of local unitary transforms. Quadratic boolean functions are related to simple graphs and it is shown that the orbit generated by successive Local Complementations on a graph can ...
cs/0502050
Generalised Bent Criteria for Boolean Functions (II)
cs.IT math.IT
In the first part of this paper [16], some results on how to compute the flat spectra of Boolean constructions w.r.t. the transforms {I,H}^n, {H,N}^n and {I,H,N}^n were presented, and the relevance of Local Complementation to the quadratic case was indicated. In this second part, the results are applied to develop re...
cs/0502052
Log Analysis Case Study Using LoGS
cs.CR cs.IR
A very useful technique a network administrator can use to identify problematic network behavior is careful analysis of logs of incoming and outgoing network flows. The challenge one faces when attempting to undertake this course of action, though, is that large networks tend to generate an extremely large quantity o...
cs/0502053
A low-cost time-hopping impulse radio system for high data rate transmission
cs.IT math.IT
We present an efficient, low-cost implementation of time-hopping impulse radio that fulfills the spectral mask mandated by the FCC and is suitable for high-data-rate, short-range communications. Key features are: (i) all-baseband implementation that obviates the need for passband components, (ii) symbol-rate (not chi...
cs/0502055
On quasi-cyclic interleavers for parallel turbo codes
cs.IT math.IT
We present an interleaving scheme that yields quasi-cyclic turbo codes. We prove that randomly chosen members of this family yield with probability almost 1 turbo codes with asymptotically optimum minimum distance, i.e. growing as a logarithm of the interleaver size. These interleavers are also very practical in term...
cs/0502057
Decomposable Problems, Niching, and Scalability of Multiobjective Estimation of Distribution Algorithms
cs.NE cs.AI
The paper analyzes the scalability of multiobjective estimation of distribution algorithms (MOEDAs) on a class of boundedly-difficult additively-separable multiobjective optimization problems. The paper illustrates that even if the linkage is correctly identified, massive multimodality of the search problems can easi...
cs/0502060
Perspectives for Strong Artificial Life
cs.AI
This text introduces the twin deadlocks of strong artificial life. Conceptualization of life is a deadlock both because of the existence of a continuum between the inert and the living, and because we only know one instance of life. Computationalism is a second deadlock since it remains a matter of faith. Nevertheles...
cs/0502063
Nonlinear MMSE Multiuser Detection Based on Multivariate Gaussian Approximation
cs.IT math.IT
In this paper, a class of nonlinear MMSE multiuser detectors are derived based on a multivariate Gaussian approximation of the multiple access interference. This approach leads to expressions identical to those describing the probabilistic data association (PDA) detector, thus providing an alternative analytical just...
cs/0502067
Master Algorithms for Active Experts Problems based on Increasing Loss Values
cs.LG cs.AI
We specify an experts algorithm with the following characteristics: (a) it uses only feedback from the actions actually chosen (bandit setup), (b) it can be applied with countably infinite expert classes, and (c) it copes with losses that may grow in time appropriately slowly. We prove loss bounds against an adaptive...
cs/0502071
Analysis of Second-order Statistics Based Semi-blind Channel Estimation in CDMA Channels
cs.IT math.IT
The performance of second order statistics (SOS) based semi-blind channel estimation in long-code DS-CDMA systems is analyzed. The covariance matrix of SOS estimates is obtained in the large system limit, and is used to analyze the large-sample performance of two SOS based semi-blind channel estimation algorithms. A ...
cs/0502072
Batch is back: CasJobs, serving multi-TB data on the Web
cs.DC cs.DB
The Sloan Digital Sky Survey (SDSS) science database describes over 140 million objects and is over 1.5 TB in size. The SDSS Catalog Archive Server (CAS) provides several levels of query interface to the SDSS data via the SkyServer website. Most queries execute in seconds or minutes. However, some queries can take ho...
cs/0502074
On sample complexity for computational pattern recognition
cs.LG cs.CC
In statistical setting of the pattern recognition problem the number of examples required to approximate an unknown labelling function is linear in the VC dimension of the target learning class. In this work we consider the question whether such bounds exist if we restrict our attention to computable pattern recognit...
cs/0502075
How far will you walk to find your shortcut: Space Efficient Synopsis Construction Algorithms
cs.DS cs.DB
In this paper we consider the wavelet synopsis construction problem without the restriction that we only choose a subset of coefficients of the original data. We provide the first near optimal algorithm. We arrive at the above algorithm by considering space efficient algorithms for the restricted version of the probl...
cs/0502076
Learning nonsingular phylogenies and hidden Markov models
cs.LG cs.CE math.PR math.ST q-bio.PE stat.TH
In this paper we study the problem of learning phylogenies and hidden Markov models. We call a Markov model nonsingular if all transition matrices have determinants bounded away from 0 (and 1). We highlight the role of the nonsingularity condition for the learning problem. Learning hidden Markov models without the no...
cs/0502077
On the Achievable Information Rates of Finite-State Input Two-Dimensional Channels with Memory
cs.IT math.IT
The achievable information rate of finite-state input two-dimensional (2-D) channels with memory is an open problem, which is relevant, e.g., for inter-symbol-interference (ISI) channels and cellular multiple-access channels. We propose a method for simulation-based computation of such information rates. We first dra...
cs/0502078
Semantical Characterizations and Complexity of Equivalences in Answer Set Programming
cs.AI cs.CC
In recent research on non-monotonic logic programming, repeatedly strong equivalence of logic programs P and Q has been considered, which holds if the programs P union R and Q union R have the same answer sets for any other program R. This property strengthens equivalence of P and Q with respect to answer sets (which...
cs/0502079
Multilevel expander codes
cs.IT math.IT
We define multilevel codes on bipartite graphs that have properties analogous to multilevel serial concatenations. A decoding algorithm is described that corrects a proportion of errors equal to half the Blokh-Zyablov bound on the minimum distance. The error probability of this algorithm has exponent similar to that ...
cs/0502080
Sensor Configuration and Activation for Field Detection in Large Sensor Arrays
cs.IT math.IT
The problems of sensor configuration and activation for the detection of correlated random fields using large sensor arrays are considered. Using results that characterize the large-array performance of sensor networks in this application, the detection capabilities of different sensor configurations are analyzed and...
cs/0502081
Tables, Memorized Semirings and Applications
cs.MA cs.DM
We define and construct a new data structure, the tables, this structure generalizes the (finite) $k$-sets sets of Eilenberg \cite{Ei}, it is versatile (one can vary the letters, the words and the coefficients). We derive from this structure a new semiring (with several semiring structures) which can be applied to th...
cs/0502082
Graphs and colorings for answer set programming
cs.AI cs.LO
We investigate the usage of rule dependency graphs and their colorings for characterizing and computing answer sets of logic programs. This approach provides us with insights into the interplay between rules when inducing answer sets. We start with different characterizations of answer sets in terms of totally colore...
cs/0502083
Impulse Radio Systems with Multiple Types of Ultra-Wideband Pulses
cs.IT math.IT
Spectral properties and performance of multi-pulse impulse radio ultra-wideband systems with pulse-based polarity randomization are analyzed. Instead of a single type of pulse transmitted in each frame, multiple types of pulses are considered, which is shown to reduce the effects of multiple-access interference. Firs...
cs/0502084
On the Typicality of the Linear Code Among the LDPC Coset Code Ensemble
cs.IT math.IT
Density evolution (DE) is one of the most powerful analytical tools for low-density parity-check (LDPC) codes on memoryless binary-input/symmetric-output channels. The case of non-symmetric channels is tackled either by the LDPC coset code ensemble (a channel symmetrizing argument) or by the generalized DE for linear...
cs/0502086
The Self-Organization of Speech Sounds
cs.LG cs.AI cs.CL cs.NE cs.RO math.DS
The speech code is a vehicle of language: it defines a set of forms used by a community to carry information. Such a code is necessary to support the linguistic interactions that allow humans to communicate. How then may a speech code be formed prior to the existence of linguistic interactions? Moreover, the human sp...
cs/0502087
Self-Replicating Strands that Self-Assemble into User-Specified Meshes
cs.NE cs.CE cs.MA
It has been argued that a central objective of nanotechnology is to make products inexpensively, and that self-replication is an effective approach to very low-cost manufacturing. The research presented here is intended to be a step towards this vision. In previous work (JohnnyVon 1.0), we simulated machines that bon...
cs/0502088
Towards a Systematic Account of Different Semantics for Logic Programs
cs.AI cs.LO
In [Hitzler and Wendt 2002, 2005], a new methodology has been proposed which allows to derive uniform characterizations of different declarative semantics for logic programs with negation. One result from this work is that the well-founded semantics can formally be understood as a stratified version of the Fitting (o...
cs/0502094
Coalition Formation: Concessions, Task Relationships and Complexity Reduction
cs.MA
Solutions to the coalition formation problem commonly assume agent rationality and, correspondingly, utility maximization. This in turn may prevent agents from making compromises. As shown in recent studies, compromise may facilitate coalition formation and increase agent utilities. In this study we leverage on those...
cs/0502095
Gradient Vector Flow Models for Boundary Extraction in 2D Images
cs.CV
The Gradient Vector Flow (GVF) is a vector diffusion approach based on Partial Differential Equations (PDEs). This method has been applied together with snake models for boundary extraction medical images segmentation. The key idea is to use a diffusion-reaction PDE to generate a new external force field that makes s...
cs/0502096
Property analysis of symmetric travelling salesman problem instances acquired through evolution
cs.NE cs.AI
We show how an evolutionary algorithm can successfully be used to evolve a set of difficult to solve symmetric travelling salesman problem instances for two variants of the Lin-Kernighan algorithm. Then we analyse the instances in those sets to guide us towards deferring general knowledge about the efficiency of the ...
cs/0503001
Top-Down Unsupervised Image Segmentation (it sounds like oxymoron, but actually it is not)
cs.CV cs.IR
Pattern recognition is generally assumed as an interaction of two inversely directed image-processing streams: the bottom-up information details gathering and localization (segmentation) stream, and the top-down information features aggregation, association and interpretation (recognition) stream. Inspired by recent ...
cs/0503006
A New Non-Iterative Decoding Algorithm for the Erasure Channel : Comparisons with Enhanced Iterative Methods
cs.IT math.IT
This paper investigates decoding of binary linear block codes over the binary erasure channel (BEC). Of the current iterative decoding algorithms on this channel, we review the Recovery Algorithm and the Guess Algorithm. We then present a Multi-Guess Algorithm extended from the Guess Algorithm and a new algorithm -- ...
cs/0503011
Shuffling a Stacked Deck: The Case for Partially Randomized Ranking of Search Engine Results
cs.IR
In-degree, PageRank, number of visits and other measures of Web page popularity significantly influence the ranking of search results by modern search engines. The assumption is that popularity is closely correlated with quality, a more elusive concept that is difficult to measure directly. Unfortunately, the correla...
cs/0503012
First-order Complete and Computationally Complete Query Languages for Spatio-Temporal Databases
cs.DB
We address a fundamental question concerning spatio-temporal database systems: ``What are exactly spatio-temporal queries?'' We define spatio-temporal queries to be computable mappings that are also generic, meaning that the result of a query may only depend to a limited extent on the actual internal representation o...
cs/0503018
Probabilistic Algorithmic Knowledge
cs.AI cs.LO
The framework of algorithmic knowledge assumes that agents use deterministic knowledge algorithms to compute the facts they explicitly know. We extend the framework to allow for randomized knowledge algorithms. We then characterize the information provided by a randomized knowledge algorithm when its answers have som...
cs/0503019
Duality Bounds on the Cut-Off Rate with Applications to Ricean Fading
cs.IT math.IT
We propose a technique to derive upper bounds on Gallager's cost-constrained random coding exponent function. Applying this technique to the non-coherent peak-power or average-power limited discrete time memoryless Ricean fading channel, we obtain the high signal-to-noise ratio (SNR) expansion of this channel's cut-o...
cs/0503020
Earlier Web Usage Statistics as Predictors of Later Citation Impact
cs.IR
The use of citation counts to assess the impact of research articles is well established. However, the citation impact of an article can only be measured several years after it has been published. As research articles are increasingly accessed through the Web, the number of times an article is downloaded can be insta...
cs/0503021
Fast-Forward on the Green Road to Open Access: The Case Against Mixing Up Green and Gold
cs.IR
This article is a critique of: "The 'Green' and 'Gold' Roads to Open Access: The Case for Mixing and Matching" by Jean-Claude Guedon (in Serials Review 30(4) 2004). Open Access (OA) means: free online access to all peer-reviewed journal articles. Jean-Claude Guedon argues against the efficacy of author self-archivi...
cs/0503022
Theory and Practice of Transactional Method Caching
cs.DB
Nowadays, tiered architectures are widely accepted for constructing large scale information systems. In this context application servers often form the bottleneck for a system's efficiency. An application server exposes an object oriented interface consisting of set of methods which are accessed by potentially remote...
cs/0503024
Fine-Grained Word Sense Disambiguation Based on Parallel Corpora, Word Alignment, Word Clustering and Aligned Wordnets
cs.AI cs.CL
The paper presents a method for word sense disambiguation based on parallel corpora. The method exploits recent advances in word alignment and word clustering based on automatic extraction of translation equivalents and being supported by available aligned wordnets for the languages in the corpus. The wordnets are al...
cs/0503026
On Generalized Computable Universal Priors and their Convergence
cs.LG cs.CC math.PR
Solomonoff unified Occam's razor and Epicurus' principle of multiple explanations to one elegant, formal, universal theory of inductive inference, which initiated the field of algorithmic information theory. His central result is that the posterior of the universal semimeasure M converges rapidly to the true sequence...
cs/0503027
Authentication with Distortion Criteria
cs.IT cs.CR cs.MM math.IT
In a variety of applications, there is a need to authenticate content that has experienced legitimate editing in addition to potential tampering attacks. We develop one formulation of this problem based on a strict notion of security, and characterize and interpret the associated information-theoretic performance lim...
cs/0503028
Stabilization of Cooperative Information Agents in Unpredictable Environment: A Logic Programming Approach
cs.LO cs.MA cs.PL
An information agent is viewed as a deductive database consisting of 3 parts: an observation database containing the facts the agent has observed or sensed from its surrounding environment, an input database containing the information the agent has obtained from other agents, and an intensional database which is a se...
cs/0503030
A Suffix Tree Approach to Email Filtering
cs.AI cs.CL
We present an approach to email filtering based on the suffix tree data structure. A method for the scoring of emails using the suffix tree is developed and a number of scoring and score normalisation functions are tested. Our results show that the character level representation of emails and classes facilitated by t...
cs/0503031
On the Scalability of Cooperative Time Synchronization in Pulse-Connected Networks
cs.IT math.IT nlin.AO
The problem of time synchronization in dense wireless networks is considered. Well established synchronization techniques suffer from an inherent scalability problem in that synchronization errors grow with an increasing number of hops across the network. In this work, a model for communication in wireless networks i...
cs/0503032
Complexity and Approximation of Fixing Numerical Attributes in Databases Under Integrity Constraints
cs.DB cs.CC
Consistent query answering is the problem of computing the answers from a database that are consistent with respect to certain integrity constraints that the database as a whole may fail to satisfy. Those answers are characterized as those that are invariant under minimal forms of restoring the consistency of the dat...