OpenRaiser/Intern-Atlas huggingface dataset:
Analysis of Multi-Scale Fractal Dimension to Classify Human Motion
Venue: arXiv cs.CV 2012
Year: 2012

In recent years there has been considerable interest in human action recognition. Several approaches have been developed in order to enhance the automatic video analysis. Although some developments have been achieved by the computer vision community, the properly classification of human motion is still a hard and challenging task. The objective of this study is to investigate the use of 3D multi-scale fractal dimension to recognize motion patterns in videos. In order to develop a robust strategy for human motion classification, we proposed a method where the Fourier transform is used to calculate the derivative in which all data points are deemed. Our results shown that different accuracy rates can be found for different databases. We believe that in specific applications our results are the first step to develop an automatic monitoring system, which can be applied in security systems, traffic monitoring, biology, physical therapy, cardiovascular disease among many others.
Remarks on random dynamical systems with inputs and outputs and a small-gain theorem for monotone RDS
Venue: arXiv cs.SY 2012
Year: 2012

This note introduces a new notion of random dynamical system with inputs and outputs, and sketches a small-gain theorem for monotone systems which generalizes a similar theorem known for deterministic systems.
Analysis and Modeling Experiment Performance Parameters of Routing Protocols in MANETs and VANETs
Venue: arXiv cs.NI 2012
Year: 2012

In this paper, a framework for experimental parameters in which Packet Delivery Ratio (PDR), effect of link duration over End-to-End Delay (E2ED) and Normalized Routing Overhead (NRO) in terms of control packets is analyzed and modeled for Mobile Ad-Hoc NETworks (MANETs) and Vehicular Ad-Hoc NETworks (VANETs) with the assumption that nodes (vehicles) are sparsely moving in two different road. Moreover, this paper contributes the performance comparison of one Proactive Routing Protocol; Destination Sequenced Distance vector (DSDV) and two reactive protocols; DYnamic Source Routing (DSR) and DYnamic MANET On-Demand (DYMO). A novel contribution of this work is enhancements in default versions of selected routing protocols. Three performance parameters; PDR, E2ED and NRO with varying scalabilities are measured to analyze the performance of selected routing protocols with their original and enhanced versions. From extensive simulations, it is observed that DSR outperforms among all three protocols at the cost of delay. NS-2 simulator is used for simulation with TwoRayGround propagation model to evaluate analytical results.
Sense me: Supporting awareness in parent-child relationships through mobile sensing
Venue: arXiv cs.HC 2012
Year: 2012

We introduce Senseμ (pronounced "sense me"), a mobile application that aims at supporting awareness in parent- child relationships through the sensing capabilities of mobile devices. We discuss the relevance of three types of awareness information: physical activity inferred from accelerometers, verbal activity during class hours inferred from microphones, and social activity inferred from Bluetooth pair-wise proximity sensing. We describe how we attempt to contextualize these sensing data with the goal of supporting parents' awareness of the educational performance and social wellbeing of their children, as well as motivating and sustaining a two-way communication between parents and teachers over the long term.
A Hybrid Forecast of Exchange Rate based on ARFIMA,Discrete Grey-Markov, and Fractal Kalman Model
Venue: arXiv cs.CE 2012
Year: 2012

We propose a hybrid forecast based on extended discrete grey Markov and variable dimension Kalman model and show that our hybrid model can improve much more the performance of forecast than traditional grey Markov and Kalman models. Our simulation results are given to demonstrate that our hybrid forecast method combined with degree of grey incidence are better than grey Markov and ARFIMA model or Kalman methods.
A Bivariate Measure of Redundant Information
Venue: arXiv cs.IT 2012
Year: 2012

We define a measure of redundant information based on projections in the space of probability distributions. Redundant information between random variables is information that is shared between those variables. But in contrast to mutual information, redundant information denotes information that is shared about the outcome of a third variable. Formalizing this concept, and being able to measure it, is required for the non-negative decomposition of mutual information into redundant and synergistic information. Previous attempts to formalize redundant or synergistic information struggle to capture some desired properties. We introduce a new formalism for redundant information and prove that it satisfies all the properties necessary outlined in earlier work, as well as an additional criterion that we propose to be necessary to capture redundancy. We also demonstrate the behaviour of this new measure for several examples, compare it to previous measures and apply it to the decomposition of transfer entropy.
Effective Enabling of Sharing and Reuse of Knowledge On Semantic Web by Ontology in Date Fruit Model
Venue: arXiv cs.AI 2012
Year: 2012

Since Organizations have recognized that knowledge constitutes a valuable intangible asset for creating and sustaining competitive advantages, knowledge sharing has a vital role in present society. It is an activity through which information is exchanged among people through different media. Many problems face the area of knowledge sharing and knowledge reuse. Currently, knowledge sharing between entities is achieved in a very ad-hoc fashion, lacking proper understanding of the meaning of the data. Ontologies can potentially solve these problems by facilitating knowledge sharing and reuse through formal and real-world semantics. Ontologies, through formal semantics, are machine-understandable. A computer can process data, annotated with references to ontologies, and through the knowledge encapsulated in the ontology, deduce facts from the original data. The date fruit is the most enduring symbol of the Sultanate's rich heritage. Creating ontology for dates will enrich the farming group and research scholars in the agro farm area.
Ubiquitous HealthCare in Wireless Body Area Networks
Venue: arXiv cs.NI 2012
Year: 2012

Recent advances in wireless communications, system on chip and low power sensor nodes allow realization of Wireless Body Area Networks (WBANs).WBANs comprise of tiny sensors, which collect information of a patient's vital signs and provide a real time feedback. In addition,WBANs also support many applications including ubiquitous healthcare, entertainment, gaming, military, etc. Ubiquitous healthcare is required by elderly people to facilitate them with instant monitoring anywhere they move around. In this paper, we provide a survey on different architectures used in WBANs for ubiquitous healthcare monitoring. Different standards and devices used in these architectures are also discussed in this paper. Finally, path loss in WBANs and its impact on communication is presented with the help of simulations performed for different models of In-Body communication and different factors (such as, attenuation, frequency, distance etc) influencing path loss in On-Body communications.
Challenges for Distributional Compositional Semantics
Venue: arXiv cs.CL 2012
Year: 2012

This paper summarises the current state-of-the art in the study of compositionality in distributional semantics, and major challenges for this area. We single out generalised quantifiers and intensional semantics as areas on which to focus attention for the development of the theory. Once suitable theories have been developed, algorithms will be needed to apply the theory to tasks. Evaluation is a major problem; we single out application to recognising textual entailment and machine translation for this purpose.
Towards the Formal Specification and Verification of Maple Programs
Venue: arXiv cs.MS 2012
Year: 2012

In this paper, we present our ongoing work and initial results on the formal specification and verification of MiniMaple (a substantial subset of Maple with slight extensions) programs. The main goal of our work is to find behavioral errors in such programs w.r.t. their specifications by static analysis. This task is more complex for widely used computer algebra languages like Maple as these are fundamentally different from classical languages: they support non-standard types of objects such as symbols, unevaluated expressions and polynomials and require abstract computer algebraic concepts and objects such as rings and orderings etc. As a starting point we have defined and formalized a syntax, semantics, type system and specification language for MiniMaple.
On Periodically Iterated Morphisms
Venue: arXiv cs.FL 2012
Year: 2012

We investigate the computational power of periodically iterated morphisms, also known as D0L systems with periodic control, PD0L systems for short. These systems give rise to a class of one-sided infinite sequences, called PD0L words. We construct a PD0L word with exponential subword complexity, thereby answering a question raised by Lepisto (1993) on the existence of such words. We solve another open problem concerning the decidability of the first-order theories of PD0L words; we show it is already undecidable whether a certain letter occurs in a PD0L word. This stands in sharp contrast to the situation for D0L words (purely morphic words), which are known to have at most quadratic subword complexity, and for which the monadic theory is decidable. The main result of our paper, leading to these answers, is that every computable word w over an alphabet Sigma can be embedded in a PD0L word u over an extended alphabet Gamma in the following two ways: (i) such that every finite prefix of w is a subword of u, and (ii) such that w is obtained from u by erasing all letters from Gamma not in Sigma. The PD0L system generating such a word u is constructed by encoding a Fractran program that computes the word w; Fractran is a programming language as powerful as Turing Machines. As a consequence of (ii), if we allow the application of finite state transducers to PD0L words, we obtain the set of all computable words. Thus the set of PD0L words is not closed under finite state transduction, whereas the set of D0L words is. It moreover follows that equality of PD0L words (given by their PD0L system) is undecidable. Finally, we show that if erasing morphisms are admitted, then the question of productivity becomes undecidable, that is, the question whether a given PD0L system defines an infinite word.
Fast Sparse Superposition Codes have Exponentially Small Error Probability for R < C
Venue: arXiv cs.IT 2012
Year: 2012

For the additive white Gaussian noise channel with average codeword power constraint, sparse superposition codes are developed. These codes are based on the statistical high-dimensional regression framework. The paper [IEEE Trans. Inform. Theory 55 (2012), 2541 - 2557] investigated decoding using the optimal maximum-likelihood decoding scheme. Here a fast decoding algorithm, called adaptive successive decoder, is developed. For any rate R less than the capacity C communication is shown to be reliable with exponentially small error probability.
Etude de Modèles à base de réseaux Bayésiens pour l'aide au diagnostic de tumeurs cérébrales
Venue: arXiv cs.AI 2012
Year: 2012

This article describes different models based on Bayesian networks RB modeling expertise in the diagnosis of brain tumors. Indeed, they are well adapted to the representation of the uncertainty in the process of diagnosis of these tumors. In our work, we first tested several structures derived from the Bayesian network reasoning performed by doctors on the one hand and structures generated automatically on the other. This step aims to find the best structure that increases diagnostic accuracy. The machine learning algorithms relate MWST-EM algorithms, SEM and SEM + T. To estimate the parameters of the Bayesian network from a database incomplete, we have proposed an extension of the EM algorithm by adding a priori knowledge in the form of the thresholds calculated by the first phase of the algorithm RBE . The very encouraging results obtained are discussed at the end of the paper
Collective Additive Tree Spanners of Bounded Tree-Breadth Graphs with Generalizations and Consequences
Venue: arXiv cs.DS 2012
Year: 2012

In this paper, we study collective additive tree spanners for families of graphs enjoying special Robertson-Seymour's tree-decompositions, and demonstrate interesting consequences of obtained results. We say that a graph $G$ {\em admits a system of $μ$ collective additive tree $r$-spanners} (resp., {\em multiplicative tree $t$-spanners}) if there is a system $\cT(G)$ of at most $μ$ spanning trees of $G$ such that for any two vertices $x,y$ of $G$ a spanning tree $T\in \cT(G)$ exists such that $d_T(x,y)\leq d_G(x,y)+r$ (resp., $d_T(x,y)\leq t\cdot d_G(x,y)$). When $μ=1$ one gets the notion of {\em additive tree $r$-spanner} (resp., {\em multiplicative tree $t$-spanner}). It is known that if a graph $G$ has a multiplicative tree $t$-spanner, then $G$ admits a Robertson-Seymour's tree-decomposition with bags of radius at most $\lceil{t/2}\rceil$ in $G$. We use this to demonstrate that there is a polynomial time algorithm that, given an $n$-vertex graph $G$ admitting a multiplicative tree $t$-spanner, constructs a system of at most $\log_2 n$ collective additive tree $O(t\log n)$-spanners of $G$. That is, with a slight increase in the number of trees and in the stretch, one can "turn" a multiplicative tree spanner into a small set of collective additive tree spanners. We extend this result by showing that if a graph $G$ admits a multiplicative $t$-spanner with tree-width $k-1$, then $G$ admits a Robertson-Seymour's tree-decomposition each bag of which can be covered with at most $k$ disks of $G$ of radius at most $\lceil{t/2}\rceil$ each. This is used to demonstrate that, for every fixed $k$, there is a polynomial time algorithm that, given an $n$-vertex graph $G$ admitting a multiplicative $t$-spanner with tree-width $k-1$, constructs a system of at most $k(1+ \log_2 n)$ collective additive tree $O(t\log n)$-spanners of $G$.
Low Complexity Blind Equalization for OFDM Systems with General Constellations
Venue: arXiv cs.IT 2012
Year: 2012

This paper proposes a low-complexity algorithm for blind equalization of data in OFDM-based wireless systems with general constellations. The proposed algorithm is able to recover data even when the channel changes on a symbol-by-symbol basis, making it suitable for fast fading channels. The proposed algorithm does not require any statistical information of the channel and thus does not suffer from latency normally associated with blind methods. We also demonstrate how to reduce the complexity of the algorithm, which becomes especially low at high SNR. Specifically, we show that in the high SNR regime, the number of operations is of the order O(LN), where L is the cyclic prefix length and N is the total number of subcarriers. Simulation results confirm the favorable performance of our algorithm.
Network Lifetime Analysis of AODV, DSR and ZRP at Different Network Parameters
Venue: arXiv cs.NI 2012
Year: 2012

Enhancement of network lifetime is a key design criterion for most of the energy constrained networks as nodes are battery operated. In multi-hop wireless network, proper utilization of battery power is very much necessary to maintain network connectivity. If the battery power of a node drains quickly then its connectivity in its neighborhood will be lost. So the study of network lifetime is very much crucial as compared to other network parameters. Considering this importance we made an attempt to study the behaviour of three most common routing protocols in ad hoc network. Extensive simulations are done on AODV, DSR and ZRP to determine the network lifetime at different node mobility and at different network load. Simulation results suggest that AODV is the most energy efficient protocol as compared to other
Oblique Pursuits for Compressed Sensing
Venue: arXiv cs.IT 2012
Year: 2012

Compressed sensing is a new data acquisition paradigm enabling universal, simple, and reduced-cost acquisition, by exploiting a sparse signal model. Most notably, recovery of the signal by computationally efficient algorithms is guaranteed for certain randomized acquisition systems. However, there is a discrepancy between the theoretical guarantees and practical applications. In applications, including Fourier imaging in various modalities, the measurements are acquired by inner products with vectors selected randomly (sampled) from a frame. Currently available guarantees are derived using a so-called restricted isometry property (RIP), which has only been shown to hold under ideal assumptions. For example, the sampling from the frame needs to be independent and identically distributed with the uniform distribution, and the frame must be tight. In practice though, one or more of the ideal assumptions is typically violated and none of the existing guarantees applies. Motivated by this discrepancy, we propose two related changes in the existing framework: (i) a generalized RIP called the restricted biorthogonality property (RBOP); and (ii) correspondingly modified versions of existing greedy pursuit algorithms, which we call oblique pursuits. Oblique pursuits are guaranteed using the RBOP without requiring ideal assumptions; hence, the guarantees apply to practical acquisition schemes. Numerical results show that oblique pursuits also perform competitively with, or sometimes better than their conventional counterparts.
Spread Spectrum based Robust Image Watermark Authentication
Venue: arXiv cs.CR 2012
Year: 2012

In this paper, a new approach to Spread Spectrum (SS) watermarking technique is introduced. This problem is particularly interesting in the field of modern multimedia applications like internet when copyright protection of digital image is required. The approach exploits two-predecessor single attractor (TPSA) cellular automata (CA) suitability to work as efficient authentication function in wavelet based SS watermarking domain. The scheme is designed from the analytical study of state transition behaviour of non-group CA and the basic cryptography/encryption scheme is significantly different from the conventional SS data hiding approaches. Experimental studies confirm that the scheme is robust in terms of confidentiality, authentication, non-repudiation and integrity. The transform domain blind watermarking technique offers better visual & statistical imperceptibility and resiliency against different types of intentional & unintentional image degradations. Interleaving and interference cancellation methods are employed to improve the robustness performance significantly compared to conventional matched filter detection.
Clustering based approach extracting collocations
Venue: arXiv cs.CL 2012
Year: 2012

The following study presents a collocation extraction approach based on clustering technique. This study uses a combination of several classical measures which cover all aspects of a given corpus then it suggests separating bigrams found in the corpus in several disjoint groups according to the probability of presence of collocations. This will allow excluding groups where the presence of collocations is very unlikely and thus reducing in a meaningful way the search space.
A GPS Pseudorange Based Cooperative Vehicular Distance Measurement Technique
Venue: arXiv cs.AI 2012
Year: 2012

Accurate vehicular localization is important for various cooperative vehicle safety (CVS) applications such as collision avoidance, turning assistant, etc. In this paper, we propose a cooperative vehicular distance measurement technique based on the sharing of GPS pseudorange measurements and a weighted least squares method. The classic double difference pseudorange solution, which was originally designed for high-end survey level GPS systems, is adapted to low-end navigation level GPS receivers for its wide availability in ground vehicles. The Carrier to Noise Ratio (CNR) of raw pseudorange measurements are taken into account for noise mitigation. We present a Dedicated Short Range Communications (DSRC) based mechanism to implement the exchange of pseudorange information among neighboring vehicles. As demonstrated in field tests, our proposed technique increases the accuracy of the distance measurement significantly compared with the distance obtained from the GPS fixes.
Positioning Accuracy Improvement via Distributed Location Estimate in Cooperative Vehicular Networks
Venue: arXiv cs.DC 2012
Year: 2012

The development of cooperative vehicle safety (CVS) applications, such as collision warnings, turning assistants, and speed advisories, etc., has received great attention in the past few years. Accurate vehicular localization is essential to enable these applications. In this study, motivated by the proliferation of the Global Positioning System (GPS) devices, and the increasing sophistication of wireless communication technologies in vehicular networks, we propose a distributed location estimate algorithm to improve the positioning accuracy via cooperative inter-vehicle distance measurement. In particular, we compute the inter-vehicle distance based on raw GPS pseudorange measurements, instead of depending on traditional radio-based ranging techniques, which usually either suffer from high hardware cost or have inadequate positioning accuracy. In addition, we improve the estimation of the vehicles' locations only based on the inaccurate GPS fixes, without using any anchors with known exact locations. The algorithm is decentralized, which enhances its practicability in highly dynamic vehicular networks. We have developed a simulation model to evaluate the performance of the proposed algorithm, and the results demonstrate that the algorithm can significantly improve the positioning accuracy.
Erasure Coding and Congestion Control for Interactive Real-Time Communication
Venue: arXiv cs.NI 2012
Year: 2012

The use of real-time applications over the Internet is a challenging problem that the QoS epoch attempted to solve by proposing the DiffServ architecture. Today, the only existing service provided by the Internet is still best-effort. As a result, multimedia applications often perform on top of a transport layer that provides a variable sending rate. In an obvious manner, this variable sending rate is an issue for these applications with strong delay constraint. In a real-time context where retransmission can not be used to ensure reliability, video quality suffers from any packet losses. In this position paper, we discuss this problem and motivate why we want to bring out a certain class of erasure coding scheme inside multimedia congestion control protocols such as TFRC.