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0809.1077
Variable Neighborhood Search for the University Lecturer-Student Assignment Problem
cs.AI
The paper presents a study of local search heuristics in general and variable neighborhood search in particular for the resolution of an assignment problem studied in the practical work of universities. Here, students have to be assigned to scientific topics which are proposed and supported by members of staff. The p...
0809.1205
On Information-Theoretic Scaling Laws for Wireless Networks
cs.IT math.IT
With the analysis of the hierarchical scheme, the potential influence of the pre-constant in deriving scaling laws is exposed. It is found that a modified hierarchical scheme can achieve a throughput arbitrarily times higher than the original one, although it is still diminishingly small compared to the linear scalin...
0809.1208
Bounds on the Capacity of the Relay Channel with States at the Source
cs.IT math.IT
This paper has been withdrawn by the authors
0809.1226
Applications of Universal Source Coding to Statistical Analysis of Time Series
cs.IT cs.AI math.IT math.ST stat.TH
We show how universal codes can be used for solving some of the most important statistical problems for time series. By definition, a universal code (or a universal lossless data compressor) can compress any sequence generated by a stationary and ergodic source asymptotically to the Shannon entropy, which, in turn, i...
0809.1241
A New Framework of Multistage Estimation
math.ST cs.LG math.PR stat.ME stat.TH
In this paper, we have established a unified framework of multistage parameter estimation. We demonstrate that a wide variety of statistical problems such as fixed-sample-size interval estimation, point estimation with error control, bounded-width confidence intervals, interval estimation following hypothesis testing...
0809.1252
Maximum Entropy Rate of Markov Sources for Systems With Non-regular Constraints
cs.IT math.IT
Using the concept of discrete noiseless channels, it was shown by Shannon in A Mathematical Theory of Communication that the ultimate performance of an encoder for a constrained system is limited by the combinatorial capacity of the system if the constraints define a regular language. In the present work, it is shown...
0809.1257
The Golden Ratio Encoder
cs.IT math.IT
This paper proposes a novel Nyquist-rate analog-to-digital (A/D) conversion algorithm which achieves exponential accuracy in the bit-rate despite using imperfect components. The proposed algorithm is based on a robust implementation of a beta-encoder where the value of the base beta is equal to golden mean. It was pr...
0809.1258
Network Protection Codes Against Link Failures Using Network Coding
cs.IT cs.NI math.IT
Protecting against link failures in communication networks is essential to increase robustness, accessibility, and reliability of data transmission. Recently, network coding has been proposed as a solution to provide agile and cost efficient network protection against link failures, which does not require data rerout...
0809.1264
Tight Bounds on Minimum Maximum Pointwise Redundancy
cs.IT math.IT
This paper presents new lower and upper bounds for the optimal compression of binary prefix codes in terms of the most probable input symbol, where compression efficiency is determined by the nonlinear codeword length objective of minimizing maximum pointwise redundancy. This objective relates to both universal model...
0809.1270
Predictive Hypothesis Identification
cs.LG math.ST stat.ML stat.TH
While statistics focusses on hypothesis testing and on estimating (properties of) the true sampling distribution, in machine learning the performance of learning algorithms on future data is the primary issue. In this paper we bridge the gap with a general principle (PHI) that identifies hypotheses with best predicti...
0809.1300
What makes a good role model
cs.IT math.IT
The role model strategy is introduced as a method for designing an estimator by approaching the output of a superior estimator that has better input observations. This strategy is shown to yield the optimal Bayesian estimator when a Markov condition is fulfilled. Two examples involving simple channels are given to il...
0809.1330
Low-Complexity Coding and Source-Optimized Clustering for Large-Scale Sensor Networks
cs.IT math.IT
We consider the distributed source coding problem in which correlated data picked up by scattered sensors has to be encoded separately and transmitted to a common receiver, subject to a rate-distortion constraint. Although near-tooptimal solutions based on Turbo and LDPC codes exist for this problem, in most cases th...
0809.1344
The Balanced Unicast and Multicast Capacity Regions of Large Wireless Networks
cs.IT math.IT
We consider the question of determining the scaling of the $n^2$-dimensional balanced unicast and the $n 2^n$-dimensional balanced multicast capacity regions of a wireless network with $n$ nodes placed uniformly at random in a square region of area $n$ and communicating over Gaussian fading channels. We identify this...
0809.1348
MBBP for improved iterative channel decoding in 802.16e WiMAX systems
cs.IT math.IT
We propose the application of multiple-bases belief-propagation, an optimized iterative decoding method, to a set of rate-1/2 LDPC codes from the IEEE 802.16e WiMAX standard. The presented approach allows for improved decoding performance when signaling over the AWGN channel. As all required operations for this metho...
0809.1366
Network Coding Security: Attacks and Countermeasures
cs.CR cs.IT cs.NI math.IT
By allowing intermediate nodes to perform non-trivial operations on packets, such as mixing data from multiple streams, network coding breaks with the ruling store and forward networking paradigm and opens a myriad of challenging security questions. Following a brief overview of emerging network coding protocols, we ...
0809.1379
A Max-Flow Min-Cut Theorem with Applications in Small Worlds and Dual Radio Networks
cs.IT cs.DM math.IT
Intrigued by the capacity of random networks, we start by proving a max-flow min-cut theorem that is applicable to any random graph obeying a suitably defined independence-in-cut property. We then show that this property is satisfied by relevant classes, including small world topologies, which are pervasive in both m...
0809.1398
Stability of Maximum likelihood based clustering methods: exploring the backbone of classifications (Who is keeping you in that community?)
physics.soc-ph cond-mat.stat-mech cs.IT math.IT physics.comp-ph physics.data-an
Components of complex systems are often classified according to the way they interact with each other. In graph theory such groups are known as clusters or communities. Many different techniques have been recently proposed to detect them, some of which involve inference methods using either Bayesian or Maximum Likeli...
0809.1493
Exploring Large Feature Spaces with Hierarchical Multiple Kernel Learning
cs.LG stat.ML
For supervised and unsupervised learning, positive definite kernels allow to use large and potentially infinite dimensional feature spaces with a computational cost that only depends on the number of observations. This is usually done through the penalization of predictor functions by Euclidean or Hilbertian norms. I...
0809.1522
On the permutation capacity of digraphs
math.CO cs.IT math.IT
We extend several results of the third author and C. Malvenuto on graph-different permutations to the case of directed graphs and introduce new open problems. Permutation capacity is a natural extension of Sperner capacity from finite directed graphs to infinite digraphs. Our subject is combinatorial in nature, but c...
0809.1551
Consistent Query Answers in the Presence of Universal Constraints
cs.DB
The framework of consistent query answers and repairs has been introduced to alleviate the impact of inconsistent data on the answers to a query. A repair is a minimally different consistent instance and an answer is consistent if it is present in every repair. In this article we study the complexity of consistent qu...
0809.1590
When is there a representer theorem? Vector versus matrix regularizers
cs.LG
We consider a general class of regularization methods which learn a vector of parameters on the basis of linear measurements. It is well known that if the regularizer is a nondecreasing function of the inner product then the learned vector is a linear combination of the input data. This result, known as the {\em repr...
0809.1593
Constructing Perfect Steganographic Systems
cs.CR cs.IT math.IT
We propose steganographic systems for the case when covertexts (containers) are generated by a finite-memory source with possibly unknown statistics. The probability distributions of covertexts with and without hidden information are the same; this means that the proposed stegosystems are perfectly secure, i.e. an ob...
0809.1618
ECOLANG - Communications Language for Ecological Simulations Network
cs.AI cs.MA
This document describes the communication language used in one multiagent system environment for ecological simulations, based on EcoDynamo simulator application linked with several intelligent agents and visualisation applications, and extends the initial definition of the language. The agents actions and perception...
0809.1686
Agent-based Ecological Model Calibration - on the Edge of a New Approach
cs.AI cs.MA
The purpose of this paper is to present a new approach to ecological model calibration -- an agent-based software. This agent works on three stages: 1- It builds a matrix that synthesizes the inter-variable relationships; 2- It analyses the steady-state sensitivity of different variables to different parameters; 3- I...
0809.1687
Incoherent dictionaries and the statistical restricted isometry property
cs.IT cs.DM math.IT math.PR
In this article we present a statistical version of the Candes-Tao restricted isometry property (SRIP for short) which holds in general for any incoherent dictionary which is a disjoint union of orthonormal bases. In addition, under appropriate normalization, the eigenvalues of the associated Gram matrix fluctuate ar...
0809.1802
Automatic Identification and Data Extraction from 2-Dimensional Plots in Digital Documents
cs.CV
Most search engines index the textual content of documents in digital libraries. However, scholarly articles frequently report important findings in figures for visual impact and the contents of these figures are not indexed. These contents are often invaluable to the researcher in various fields, for the purposes of...
0809.1900
Distributed Detection in Sensor Networks with Limited Range Multi-Modal Sensors
cs.IT math.IT
We consider a multi-object detection problem over a sensor network (SNET) with limited range multi-modal sensors. Limited range sensing environment arises in a sensing field prone to signal attenuation and path losses. The general problem complements the widely considered decentralized detection problem where all sen...
0809.1910
Reliable Communications with Asymmetric Codebooks: An Information Theoretic Analysis of Robust Signal Hashing
cs.IT math.IT
In this paper, a generalization of the traditional point-to-point to communication setup, which is named as "reliable communications with asymmetric codebooks", is proposed. Under the assumption of independent identically distributed (i.i.d) encoder codewords, it is proven that the operational capacity of the system ...
0809.1916
Randomized Distributed Configuration Management of Wireless Networks: Multi-layer Markov Random Fields and Near-Optimality
cs.DC cs.AI
Distributed configuration management is imperative for wireless infrastructureless networks where each node adjusts locally its physical and logical configuration through information exchange with neighbors. Two issues remain open. The first is the optimality. The second is the complexity. We study these issues throu...
0809.1963
Materialized View Selection by Query Clustering in XML Data Warehouses
cs.DB
XML data warehouses form an interesting basis for decision-support applications that exploit complex data. However, native XML database management systems currently bear limited performances and it is necessary to design strategies to optimize them. In this paper, we propose an automatic strategy for the selection of...
0809.1965
Dynamic index selection in data warehouses
cs.DB
Analytical queries defined on data warehouses are complex and use several join operations that are very costly, especially when run on very large data volumes. To improve response times, data warehouse administrators casually use indexing techniques. This task is nevertheless complex and fastidious. In this paper, we...
0809.1971
Knowledge and Metadata Integration for Warehousing Complex Data
cs.DB
With the ever-growing availability of so-called complex data, especially on the Web, decision-support systems such as data warehouses must store and process data that are not only numerical or symbolic. Warehousing and analyzing such data requires the joint exploitation of metadata and domain-related knowledge, which...
0809.1981
A Join Index for XML Data Warehouses
cs.DB
XML data warehouses form an interesting basis for decision-support applications that exploit complex data. However, native-XML database management systems (DBMSs) currently bear limited performances and it is necessary to research for ways to optimize them. In this paper, we propose a new join index that is specifica...
0809.2075
Low congestion online routing and an improved mistake bound for online prediction of graph labeling
cs.DS cs.DM cs.LG
In this paper, we show a connection between a certain online low-congestion routing problem and an online prediction of graph labeling. More specifically, we prove that if there exists a routing scheme that guarantees a congestion of $\alpha$ on any edge, there exists an online prediction algorithm with mistake bound...
0809.2085
Clustered Multi-Task Learning: A Convex Formulation
cs.LG
In multi-task learning several related tasks are considered simultaneously, with the hope that by an appropriate sharing of information across tasks, each task may benefit from the others. In the context of learning linear functions for supervised classification or regression, this can be achieved by including a prio...
0809.2136
The Potluck Problem
cs.GT cs.MA
This paper proposes the Potluck Problem as a model for the behavior of independent producers and consumers under standard economic assumptions, as a problem of resource allocation in a multi-agent system in which there is no explicit communication among the agents.
0809.2147
Investigation on Multiuser Diversity in Spectrum Sharing Based Cognitive Radio Networks
cs.IT math.IT
A new form of multiuser diversity, named \emph{multiuser interference diversity}, is investigated for opportunistic communications in cognitive radio (CR) networks by exploiting the mutual interference between the CR and the existing primary radio (PR) links. The multiuser diversity gain and ergodic throughput are an...
0809.2148
Cognitive Beamforming Made Practical: Effective Interference Channel and Learning-Throughput Tradeoff
cs.IT math.IT
This paper studies the transmit strategy for a secondary link or the so-called cognitive radio (CR) link under opportunistic spectrum sharing with an existing primary radio (PR) link. It is assumed that the CR transmitter is equipped with multi-antennas, whereby transmit precoding and power control can be jointly dep...
0809.2152
Informed Network Coding for Minimum Decoding Delay
cs.IT math.IT
Network coding is a highly efficient data dissemination mechanism for wireless networks. Since network coded information can only be recovered after delivering a sufficient number of coded packets, the resulting decoding delay can become problematic for delay-sensitive applications such as real-time media streaming. ...
0809.2168
Fairness in Combinatorial Auctioning Systems
cs.GT cs.MA
One of the Multi-Agent Systems that is widely used by various government agencies, buyers and sellers in a market economy, in such a manner so as to attain optimized resource allocation, is the Combinatorial Auctioning System (CAS). We study another important aspect of resource allocations in CAS, namely fairness. We...
0809.2226
Relay vs. User Cooperation in Time-Duplexed Multiaccess Networks
cs.IT math.IT
The performance of user-cooperation in a multi-access network is compared to that of using a wireless relay. Using the total transmit and processing power consumed at all nodes as a cost metric, the outage probabilities achieved by dynamic decode-and-forward (DDF) and amplify-and-forward (AF) are compared for the two...
0809.2315
On the Construction of Skew Quasi-Cyclic Codes
cs.IT cs.DM math.IT math.RA
In this paper we study a special type of quasi-cyclic (QC) codes called skew QC codes. This set of codes is constructed using a non-commutative ring called the skew polynomial rings $F[x;\theta ]$. After a brief description of the skew polynomial ring $F[x;\theta ]$ it is shown that skew QC codes are left submodules ...
0809.2350
Random Linear Network Coding For Time Division Duplexing: When To Stop Talking And Start Listening
cs.IT math.IT
A new random linear network coding scheme for reliable communications for time division duplexing channels is proposed. The setup assumes a packet erasure channel and that nodes cannot transmit and receive information simultaneously. The sender transmits coded data packets back-to-back before stopping to wait for the...
0809.2421
Electricity Demand and Energy Consumption Management System
cs.AI cs.CE
This project describes the electricity demand and energy consumption management system and its application to Southern Peru smelter. It is composed of an hourly demand-forecasting module and of a simulation component for a plant electrical system. The first module was done using dynamic neural networks with backpropa...
0809.2446
High-Rate Space-Time Coded Large MIMO Systems: Low-Complexity Detection and Channel Estimation
cs.IT math.IT
In this paper, we present a low-complexity algorithm for detection in high-rate, non-orthogonal space-time block coded (STBC) large-MIMO systems that achieve high spectral efficiencies of the order of tens of bps/Hz. We also present a training-based iterative detection/channel estimation scheme for such large STBC MI...
0809.2508
A fast approach for overcomplete sparse decomposition based on smoothed L0 norm
cs.IT math.IT
In this paper, a fast algorithm for overcomplete sparse decomposition, called SL0, is proposed. The algorithm is essentially a method for obtaining sparse solutions of underdetermined systems of linear equations, and its applications include underdetermined Sparse Component Analysis (SCA), atomic decomposition on ove...
0809.2532
Multidimensional Visualization of Oracle Performance Using Barry007
cs.PF cs.DB
Most generic performance tools display only system-level performance data using 2-dimensional plots or diagrams and this limits the informational detail that can be displayed. Moreover, a modern relational database system, like Oracle, can concurrently serve thousands of client processes with different workload chara...
0809.2546
Depth as Randomness Deficiency
cs.CC cs.IT math.IT
Depth of an object concerns a tradeoff between computation time and excess of program length over the shortest program length required to obtain the object. It gives an unconditional lower bound on the computation time from a given program in absence of auxiliary information. Variants known as logical depth and compu...
0809.2553
Normalized Information Distance
cs.IR cs.AI
The normalized information distance is a universal distance measure for objects of all kinds. It is based on Kolmogorov complexity and thus uncomputable, but there are ways to utilize it. First, compression algorithms can be used to approximate the Kolmogorov complexity if the objects have a string representation. Se...
0809.2639
Code diversity in multiple antenna wireless communication
cs.IT math.IT
The standard approach to the design of individual space-time codes is based on optimizing diversity and coding gains. This geometric approach leads to remarkable examples, such as perfect space-time block codes, for which the complexity of Maximum Likelihood (ML) decoding is considerable. Code diversity is an alterna...
0809.2680
Mathematical Tool of Discrete Dynamic Modeling of Complex Systems in Control Loop
cs.MA cs.CE
In this paper we present a method of discrete modeling and analysis of multi-level dynamics of complex large-scale hierarchical dynamic systems subject to external dynamic control mechanism. In a model each state describes parallel dynamics and simultaneous trends of changes in system parameters. The essence of the a...
0809.2686
An MAS-Based ETL Approach for Complex Data
cs.DB
In a data warehousing process, the phase of data integration is crucial. Many methods for data integration have been published in the literature. However, with the development of the Internet, the availability of various types of data (images, texts, sounds, videos, databases...) has increased, and structuring such d...
0809.2687
Frequent itemsets mining for database auto-administration
cs.DB
With the wide development of databases in general and data warehouses in particular, it is important to reduce the tasks that a database administrator must perform manually. The aim of auto-administrative systems is to administrate and adapt themselves automatically without loss (or even with a gain) in performance. ...
0809.2688
A Complex Data Warehouse for Personalized, Anticipative Medicine
cs.DB
With the growing use of new technologies, healthcare is nowadays undergoing significant changes. Information-based medicine has to exploit medical decision-support systems and requires the analysis of various, heterogeneous data, such as patient records, medical images, biological analysis results, etc. In this paper...
0809.2691
Expressing OLAP operators with the TAX XML algebra
cs.DB
With the rise of XML as a standard for representing business data, XML data warehouses appear as suitable solutions for Web-based decision-support applications. In this context, it is necessary to allow OLAP analyses over XML data cubes (XOLAP). Thus, XQuery extensions are needed. To help define a formal framework an...
0809.2754
Algorithmic information theory
cs.IT cs.LG math.IT math.ST stat.TH
We introduce algorithmic information theory, also known as the theory of Kolmogorov complexity. We explain the main concepts of this quantitative approach to defining `information'. We discuss the extent to which Kolmogorov's and Shannon's information theory have a common purpose, and where they are fundamentally dif...
0809.2768
Hubs and Clusters in the Evolving U. S. Internal Migration Network
physics.soc-ph cs.SI physics.data-an stat.AP
Most nations of the world periodically publish N x N origin-destination tables, recording the number of people who lived in geographic subdivision i at time t and j at t+1. We have developed and widely applied to such national tables and other analogous (weighted, directed) socioeconomic networks, a two-stage--double...
0809.2792
Predicting Abnormal Returns From News Using Text Classification
cs.LG cs.AI
We show how text from news articles can be used to predict intraday price movements of financial assets using support vector machines. Multiple kernel learning is used to combine equity returns with text as predictive features to increase classification performance and we develop an analytic center cutting plane meth...
0809.2835
Fundamental Constraints on Multicast Capacity Regions
cs.IT math.IT
Much of the existing work on the broadcast channel focuses only on the sending of private messages. In this work we examine the scenario where the sender also wishes to transmit common messages to subsets of receivers. For an L user broadcast channel there are 2L - 1 subsets of receivers and correspondingly 2L - 1 in...
0809.2840
Spectrum Sharing between Wireless Networks
cs.IT math.IT
We consider the problem of two wireless networks operating on the same (presumably unlicensed) frequency band. Pairs within a given network cooperate to schedule transmissions, but between networks there is competition for spectrum. To make the problem tractable, we assume transmissions are scheduled according to a r...
0809.2931
An Efficient Algorithm for Cooperative Spectrum Sensing in Cognitive Radio Networks
cs.IT math.IT
We consider the problem of Spectrum Sensing in Cognitive Radio Systems. We have developed a distributed algorithm that the Secondary users can run to sense the channel cooperatively. It is based on sequential detection algorithms which optimally use the past observations. We use the algorithm on secondary users with ...
0809.2965
On Time-Bounded Incompressibility of Compressible Strings and Sequences
cs.CC cs.IT math.IT
For every total recursive time bound $t$, a constant fraction of all compressible (low Kolmogorov complexity) strings is $t$-bounded incompressible (high time-bounded Kolmogorov complexity); there are uncountably many infinite sequences of which every initial segment of length $n$ is compressible to $\log n$ yet $t$-...
0809.2968
Bounds on Covering Codes with the Rank Metric
cs.IT math.IT
In this paper, we investigate geometrical properties of the rank metric space and covering properties of rank metric codes. We first establish an analytical expression for the intersection of two balls with rank radii, and then derive an upper bound on the volume of the union of multiple balls with rank radii. Using ...
0809.3010
Improved Upper Bounds for the Information Rates of the Secret Sharing Schemes Induced by the Vamos Matroid
cs.CR cs.IT math.IT
An access structure specifying the qualified sets of a secret sharing scheme must have information rate less than or equal to one. The Vamos matroid induces two non-isomorphic access structures V1 and V6, which were shown by Marti-Farre and Padro to have information rates of at least 3/4. Beimel, Livne, and Padro sho...
0809.3023
Graph-based Logic and Sketches
math.CT cs.IT math.IT math.LO
We present the basic ideas of forms (a generalization of Ehresmann's sketches) and their theories and models, more explicitly than in previous expositions. Forms provide the ability to specify mathematical structures and data types in any appropriate category, including many types of structures (e.g. function spaces)...
0809.3027
Finding links and initiators: a graph reconstruction problem
cs.AI cs.DB physics.soc-ph
Consider a 0-1 observation matrix M, where rows correspond to entities and columns correspond to signals; a value of 1 (or 0) in cell (i,j) of M indicates that signal j has been observed (or not observed) in entity i. Given such a matrix we study the problem of inferring the underlying directed links between entities...
0809.3035
Interference Alignment for Line-of-Sight Channels
cs.IT math.IT
The fully connected K-user interference channel is studied in a multipath environment with bandwidth W. We show that when each link consists of D physical paths, the total spectral efficiency can grow {\it linearly} with K. This result holds not merely in the limit of large transmit power P, but for any fixed P, and ...
0809.3044
Kinetostatic Performance of a Planar Parallel Mechanism with Variable Actuation
cs.RO
This paper deals with a new planar parallel mechanism with variable actuation and its kinetostatic performance. A drawback of parallel mechanisms is the non homogeneity of kinetostatic performance within their workspace. The common approach to solve this problem is the introduction of actuation redundancy, that invol...
0809.3083
Supervised Dictionary Learning
cs.CV
It is now well established that sparse signal models are well suited to restoration tasks and can effectively be learned from audio, image, and video data. Recent research has been aimed at learning discriminative sparse models instead of purely reconstructive ones. This paper proposes a new step in that direction, w...
0809.3140
Monadic Datalog over Finite Structures with Bounded Treewidth
cs.DB cs.CC cs.LO
Bounded treewidth and Monadic Second Order (MSO) logic have proved to be key concepts in establishing fixed-parameter tractability results. Indeed, by Courcelle's Theorem we know: Any property of finite structures, which is expressible by an MSO sentence, can be decided in linear time (data complexity) if the structu...
0809.3159
A Geometrical Description of the SINR Region of the Gaussian Interference Channel: the two and three-user case
cs.IT math.IT
This paper addresses the problem of computing the achievable rates for two (and three) users sharing a same frequency band without coordination and thus interfering with each other. It is thus primarily related to the field of cognitive radio studies as we look for the achievable increase in the spectrum use efficien...
0809.3170
A New Framework of Multistage Hypothesis Tests
math.ST cs.LG math.PR stat.ME stat.TH
In this paper, we have established a general framework of multistage hypothesis tests which applies to arbitrarily many mutually exclusive and exhaustive composite hypotheses. Within the new framework, we have constructed specific multistage tests which rigorously control the risk of committing decision errors and ar...
0809.3179
Kinematic and Dynamic Analyses of the Orthoglide 5-axis
cs.RO
This paper deals with the kinematic and dynamic analyses of the Orthoglide 5-axis, a five-degree-of-freedom manipulator. It is derived from two manipulators: i) the Orthoglide 3-axis; a three dof translational manipulator and ii) the Agile eye; a parallel spherical wrist. First, the kinematic and dynamic models of th...
0809.3180
Singularity Analysis of Limited-dof Parallel Manipulators using Grassmann-Cayley Algebra
cs.RO
This paper characterizes geometrically the singularities of limited DOF parallel manipulators. The geometric conditions associated with the dependency of six Pl\"ucker vector of lines (finite and infinite) constituting the rows of the inverse Jacobian matrix are formulated using Grassmann-Cayley algebra. Manipulators...
0809.3181
Framework for Dynamic Evaluation of Muscle Fatigue in Manual Handling Work
cs.RO
Muscle fatigue is defined as the point at which the muscle is no longer able to sustain the required force or work output level. The overexertion of muscle force and muscle fatigue can induce acute pain and chronic pain in human body. When muscle fatigue is accumulated, the functional disability can be resulted as mu...
0809.3182
SINGULAB - A Graphical user Interface for the Singularity Analysis of Parallel Robots based on Grassmann-Cayley Algebra
cs.RO
This paper presents SinguLab, a graphical user interface for the singularity analysis of parallel robots. The algorithm is based on Grassmann-Cayley algebra. The proposed tool is interactive and introduces the designer to the singularity analysis performed by this method, showing all the stages along the procedure an...
0809.3187
A Control Variate Approach for Improving Efficiency of Ensemble Monte Carlo
cs.CE cond-mat.stat-mech stat.CO
In this paper we present a new approach to control variates for improving computational efficiency of Ensemble Monte Carlo. We present the approach using simulation of paths of a time-dependent nonlinear stochastic equation. The core idea is to extract information at one or more nominal model parameters and use this ...
0809.3204
Extended ASP tableaux and rule redundancy in normal logic programs
cs.AI
We introduce an extended tableau calculus for answer set programming (ASP). The proof system is based on the ASP tableaux defined in [Gebser&Schaub, ICLP 2006], with an added extension rule. We investigate the power of Extended ASP Tableaux both theoretically and empirically. We study the relationship of Extended ASP...
0809.3250
Using descriptive mark-up to formalize translation quality assessment
cs.CL
The paper deals with using descriptive mark-up to emphasize translation mistakes. The author postulates the necessity to develop a standard and formal XML-based way of describing translation mistakes. It is considered to be important for achieving impersonal translation quality assessment. Marked-up translations can ...
0809.3273
Direct and Reverse Secret-Key Capacities of a Quantum Channel
quant-ph cs.CR cs.IT math.IT physics.optics
We define the direct and reverse secret-key capacities of a memoryless quantum channel as the optimal rates that entanglement-based quantum key distribution protocols can reach by using a single forward classical communication (direct reconciliation) or a single feedback classical communication (reverse reconciliatio...
0809.3352
Generalized Prediction Intervals for Arbitrary Distributed High-Dimensional Data
cs.CV cs.AI cs.LG
This paper generalizes the traditional statistical concept of prediction intervals for arbitrary probability density functions in high-dimensional feature spaces by introducing significance level distributions, which provides interval-independent probabilities for continuous random variables. The advantage of the tra...
0809.3365
Algebraic reduction for space-time codes based on quaternion algebras
cs.IT math.IT
In this paper we introduce a new right preprocessing method for the decoding of 2x2 algebraic STBCs, called algebraic reduction, which exploits the multiplicative structure of the code. The principle of the new reduction is to absorb part of the channel into the code, by approximating the channel matrix with an eleme...
0809.3370
Achievability of the Rate ${1/2}\log(1+\es)$ in the Discrete-Time Poisson Channel
cs.IT math.IT
A simple lower bound to the capacity of the discrete-time Poisson channel with average energy $\es$ is derived. The rate ${1/2}\log(1+\es)$ is shown to be the generalized mutual information of a modified minimum-distance decoder, when the input follows a gamma distribution of parameter 1/2 and mean $\es$.
0809.3384
Changing Assembly Modes without Passing Parallel Singularities in Non-Cuspidal 3-R\underline{P}R Planar Parallel Robots
cs.RO
This paper demonstrates that any general 3-DOF three-legged planar parallel robot with extensible legs can change assembly modes without passing through parallel singularities (configurations where the mobile platform loses its stiffness). While the results are purely theoretical, this paper questions the very defini...
0809.3447
An Exploratory Study of Calendar Use
cs.HC cs.IR
In this paper, we report on findings from an ethnographic study of how people use their calendars for personal information management (PIM). Our participants were faculty, staff and students who were not required to use or contribute to any specific calendaring solution, but chose to do so anyway. The study was condu...
0809.3479
Fermions and Loops on Graphs. I. Loop Calculus for Determinant
cond-mat.stat-mech cond-mat.dis-nn cs.CC cs.IT hep-th math.IT
This paper is the first in the series devoted to evaluation of the partition function in statistical models on graphs with loops in terms of the Berezin/fermion integrals. The paper focuses on a representation of the determinant of a square matrix in terms of a finite series, where each term corresponds to a loop on ...
0809.3481
Fermions and Loops on Graphs. II. Monomer-Dimer Model as Series of Determinants
cond-mat.stat-mech cond-mat.dis-nn cs.CC cs.IT hep-th math.IT
We continue the discussion of the fermion models on graphs that started in the first paper of the series. Here we introduce a Graphical Gauge Model (GGM) and show that : (a) it can be stated as an average/sum of a determinant defined on the graph over $\mathbb{Z}_{2}$ (binary) gauge field; (b) it is equivalent to the...
0809.3540
A Note on the Equivalence of Gibbs Free Energy and Information Theoretic Capacity
cond-mat.stat-mech cs.IT math.IT
The minimization of Gibbs free energy is based on the changes in work and free energy that occur in a physical or chemical system. The maximization of mutual information, the capacity, of a noisy channel is determined based on the marginal probabilities and conditional entropies associated with a communications syste...
0809.3546
Universal Secure Network Coding via Rank-Metric Codes
cs.IT cs.CR math.IT
The problem of securing a network coding communication system against an eavesdropper adversary is considered. The network implements linear network coding to deliver n packets from source to each receiver, and the adversary can eavesdrop on \mu arbitrarily chosen links. The objective is to provide reliable communica...
0809.3554
The Approximate Capacity of the Many-to-One and One-to-Many Gaussian Interference Channels
cs.IT math.IT
Recently, Etkin, Tse, and Wang found the capacity region of the two-user Gaussian interference channel to within one bit/s/Hz. A natural goal is to apply this approach to the Gaussian interference channel with an arbitrary number of users. We make progress towards this goal by finding the capacity region of the many-...
0809.3600
On the Capacity Improvement of Multicast Traffic with Network Coding
cs.IT math.IT
In this paper, we study the contribution of network coding (NC) in improving the multicast capacity of random wireless ad hoc networks when nodes are endowed with multi-packet transmission (MPT) and multi-packet reception (MPR) capabilities. We show that a per session throughput capacity of $\Theta(nT^{3}(n))$, where...
0809.3618
Robust Near-Isometric Matching via Structured Learning of Graphical Models
cs.CV cs.LG
Models for near-rigid shape matching are typically based on distance-related features, in order to infer matches that are consistent with the isometric assumption. However, real shapes from image datasets, even when expected to be related by "almost isometric" transformations, are actually subject not only to noise b...
0809.3650
Hierarchical Bayesian sparse image reconstruction with application to MRFM
physics.data-an cs.IT math.IT stat.ME
This paper presents a hierarchical Bayesian model to reconstruct sparse images when the observations are obtained from linear transformations and corrupted by an additive white Gaussian noise. Our hierarchical Bayes model is well suited to such naturally sparse image applications as it seamlessly accounts for propert...
0809.3688
Mathematical and computer tools of discrete dynamic modeling and analysis of complex systems in control loop
cs.CE cs.MA
We present a method of discrete modeling and analysis of multilevel dynamics of complex large-scale hierarchical dynamic systems subject to external dynamic control mechanism. Architectural model of information system supporting simulation and analysis of dynamic processes and development scenarios (strategies) of co...
0809.3690
Modeling and Control with Local Linearizing Nadaraya Watson Regression
cs.CV
Black box models of technical systems are purely descriptive. They do not explain why a system works the way it does. Thus, black box models are insufficient for some problems. But there are numerous applications, for example, in control engineering, for which a black box model is absolutely sufficient. In this artic...
0809.3731
Uncertainty Relations for Shift-Invariant Analog Signals
cs.IT math.IT
The past several years have witnessed a surge of research investigating various aspects of sparse representations and compressed sensing. Most of this work has focused on the finite-dimensional setting in which the goal is to decompose a finite-length vector into a given finite dictionary. Underlying many of these re...
0809.4019
Throughput Scaling of Wireless Networks With Random Connections
cs.IT math.IT
This work studies the throughput scaling laws of ad hoc wireless networks in the limit of a large number of nodes. A random connections model is assumed in which the channel connections between the nodes are drawn independently from a common distribution. Transmitting nodes are subject to an on-off strategy, and rece...
0809.4058
Target Localization Accuracy Gain in MIMO Radar Based Systems
cs.IT math.IT
This paper presents an analysis of target localization accuracy, attainable by the use of MIMO (Multiple-Input Multiple-Output) radar systems, configured with multiple transmit and receive sensors, widely distributed over a given area. The Cramer-Rao lower bound (CRLB) for target localization accuracy is developed fo...
0809.4059
Information transmission in oscillatory neural activity
q-bio.NC cs.IT math.IT q-bio.QM
Periodic neural activity not locked to the stimulus or to motor responses is usually ignored. Here, we present new tools for modeling and quantifying the information transmission based on periodic neural activity that occurs with quasi-random phase relative to the stimulus. We propose a model to reproduce characteris...
0809.4086
Learning Hidden Markov Models using Non-Negative Matrix Factorization
cs.LG cs.AI cs.IT math.IT
The Baum-Welsh algorithm together with its derivatives and variations has been the main technique for learning Hidden Markov Models (HMM) from observational data. We present an HMM learning algorithm based on the non-negative matrix factorization (NMF) of higher order Markovian statistics that is structurally differe...