OpenRaiser/Intern-Atlas huggingface dataset:
Reasoning with Data-Centric Business Processes
Venue: arXiv cs.LO 2012
Year: 2012

We describe an approach to modelling and reasoning about data-centric business processes and present a form of general model checking. Our technique extends existing approaches, which explore systems only from concrete initial states. Specifically, we model business processes in terms of smaller fragments, whose possible interactions are constrained by first-order logic formulae. In turn, process fragments are connected graphs annotated with instructions to modify data. Correctness properties concerning the evolution of data with respect to processes can be stated in a first-order branching-time logic over built-in theories, such as linear integer arithmetic, records and arrays. Solving general model checking problems over this logic is considerably harder than model checking when a concrete initial state is given. To this end, we present a tableau procedure that reduces these model checking problems to first-order logic over arithmetic. The resulting proof obligations are passed on to appropriate "off-the-shelf" theorem provers. We also detail our modelling approach, describe the reasoning components and report on first experiments.
Generalized Network Tomography
Venue: arXiv cs.NI 2012
Year: 2012

For successful estimation, the usual network tomography algorithms crucially require i) end-to-end data generated using multicast probe packets, real or emulated, and ii) the network to be a tree rooted at a single sender with destinations at leaves. These requirements, consequently, limit their scope of application. In this paper, we address successfully a general problem, henceforth called generalized network tomography, wherein the objective is to estimate the link performance parameters for networks with arbitrary topologies using only end-to-end measurements of pure unicast probe packets. Mathematically, given a binary matrix $A,$ we propose a novel algorithm to uniquely estimate the distribution of $X,$ a vector of independent non-negative random variables, given only IID samples of the components of the random vector $Y = AX.$ This algorithm, in fact, does not even require any prior knowledge of the unknown distributions. The idea is to approximate the distribution of each component of $X$ using linear combinations of known exponential bases and estimate the unknown weights. These weights are obtained by solving a set of polynomial systems based on the moment generating function of the components of $Y.$ For unique identifiability, it is only required that every pair of columns of the matrix $A$ be linearly independent, a property that holds true for the routing matrices of all multicast tree networks. Matlab based simulations have been included to illustrate the potential of the proposed scheme.
Face Recognition Algorithms based on Transformed Shape Features
Venue: arXiv cs.CV 2012
Year: 2012

Human face recognition is, indeed, a challenging task, especially under the illumination and pose variations. We examine in the present paper effectiveness of two simple algorithms using coiflet packet and Radon transforms to recognize human faces from some databases of still gray level images, under the environment of illumination and pose variations. Both the algorithms convert 2-D gray level training face images into their respective depth maps or physical shape which are subsequently transformed by Coiflet packet and Radon transforms to compute energy for feature extraction. Experiments show that such transformed shape features are robust to illumination and pose variations. With the features extracted, training classes are optimally separated through linear discriminant analysis (LDA), while classification for test face images is made through a k-NN classifier, based on L1 norm and Mahalanobis distance measures. Proposed algorithms are then tested on face images that differ in illumination,expression or pose separately, obtained from three databases,namely, ORL, Yale and Essex-Grimace databases. Results, so obtained, are compared with two different existing algorithms.Performance using Daubechies wavelets is also examined. It is seen that the proposed Coiflet packet and Radon transform based algorithms have significant performance, especially under different illumination conditions and pose variation. Comparison shows the proposed algorithms are superior.
Quantifying Spatiotemporal Stability by means of Entropy: Approach and Motivations
Venue: arXiv cs.NI 2012
Year: 2012

Several studies demonstrate that there are critical differences between real wireless networks and simulation models. This finding has permitted to extract spatial and temporal properties for links and to provide efficient methods as biased link sampling to guarantee efficient routing structure. Other works have focused on computing metrics to improve routing, specially the reuse of the measure of entropy. From there, rises the idea of formulating a new measure of entropy that gives an overview of the spatiotemporal stability of a link. This measure will rely on spatial and temporal properties of links and fed with the efficiency of biased link sampling.
Full Data Controlled Web-Based Feed Aggregator
Venue: arXiv cs.SE 2012
Year: 2012

Feed syndication is analogous to electronic newsletters, both are aimed at delivering feeds to subscribers; the difference is that while newsletter subscription requires e-mail and exposed you to spam and security challenges, feed syndication ensures that you only get what you requested for. This paper reports a review on the state of the art of feed aggregation technology and the development of a locally hosted web based feed aggregator as a research tool using the core features of WordPress; the software was further enhanced with plugins and widgets for dynamic content publishing, database and object caching, social web syndication, back-up and maintenance, among others. The results highlight the current developments in software re-use and describes; how open source content management systems can be used for both online and offline publishing, a means whereby feed aggregator users can control and share feed data, as well as how web developers can focus on extending the features of built-in software libraries in applications rather than reinventing the wheel.
IP over Voice-over-IP for censorship circumvention
Venue: arXiv cs.CR 2012
Year: 2012

Open communication over the Internet poses a serious threat to countries with repressive regimes, leading them to develop and deploy network-based censorship mechanisms within their networks. Existing censorship circumvention systems face different difficulties in providing unobservable communication with their clients; this limits their availability and poses threats to their users. To provide the required unobservability, several recent circumvention systems suggest modifying Internet routers running outside the censored region to intercept and redirect packets to censored destinations. However, these approaches require modifications to ISP networks, and hence requires cooperation from ISP operators and/or network equipment vendors, presenting a substantial deployment challenge. In this report we propose a deployable and unobservable censorship-resistant infrastructure, called FreeWave. FreeWave works by modulating a client's Internet connections into acoustic signals that are carried over VoIP connections. Such VoIP connections are targeted to a server, FreeWave server, that extracts the tunneled traffic of clients and proxies them to the uncensored Internet. The use of actual VoIP connections, as opposed to traffic morphing, allows FreeWave to relay its VoIP connections through oblivious VoIP nodes, hence keeping itself unblockable from censors that perform IP address blocking. Also, the use of end-to-end encryption prevents censors from identifying FreeWave's VoIP connections using packet content filtering technologies, like deep-packet inspection. We prototype the designed FreeWave system over the popular VoIP system of Skype. We show that FreeWave is able to reliably achieve communication bandwidths that are sufficient for web browsing, even when clients are far distanced from the FreeWave server.
Performance Evaluation of Spread Spectrum Watermarking using Error Control Coding
Venue: arXiv cs.CR 2012
Year: 2012

This paper proposes an oblivious watermarking algorithm with blind detection approach for high volume data hiding in image signals. We present a detection reliable signal adaptive embedding scheme for multiple messages in selective sub-bands of wavelet (DWT) coefficients using direct sequence spread spectrum (DS-SS) modulation technique. Here the impact of volumetric distortion sources is analyzed on the ability of analytical bounds in order to recover the watermark messages. In this context, the joint source-channel coding scheme has been employed to obtain the better control of the system robustness. This structure prevents the desynchronisation between encoder and decoder due to selective embedding. The experimental results obtained for Spread Spectrum (SS) transformed domain watermarking demonstrate the efficiency of the proposed system. This algorithmic architecture utilizes the existing allocated bandwidth in the data transmission channel in a more efficient manner.
Effective Cost Mechanism for Cloudlet Retransmission and Prioritized VM Scheduling Mechanism over Broker Virtual Machine Communication Framework
Venue: arXiv cs.DC 2012
Year: 2012

In current scenario cloud computing is most widely increasing platform for task execution. Lot of research is going on to cut down the cost and execution time. In this paper, we propose an efficient algorithm to have an effective and fast execution of task assigned by the user. We proposed an effective communication framework between broker and virtual machine for assigning the task and fetching the results in optimum time and cost using Broker Virtual Machine Communication Framework (BVCF). We implement it over cloudsim under VM scheduling policies by modification based on Virtual Machine Cost. Scheduling over Virtual Machine as well as over Cloudlets and Retransmission of Cloudlets are the basic building blocks of the proposed work on which the whole architecture is dependent. Execution of cloudlets is being analyzed over Round Robin and FCFS scheduling policy.
The Outage Probability of a Finite Ad Hoc Network in Nakagami Fading
Venue: arXiv cs.IT 2012
Year: 2012

An ad hoc network with a finite spatial extent and number of nodes or mobiles is analyzed. The mobile locations may be drawn from any spatial distribution, and interference-avoidance protocols or protection against physical collisions among the mobiles may be modeled by placing an exclusion zone around each radio. The channel model accounts for the path loss, Nakagami fading, and shadowing of each received signal. The Nakagami m-parameter can vary among the mobiles, taking any positive value for each of the interference signals and any positive integer value for the desired signal. The analysis is governed by a new exact expression for the outage probability, defined to be the probability that the signal-to-interference-and-noise ratio (SINR) drops below a threshold, and is conditioned on the network geometry and shadowing factors, which have dynamics over much slower timescales than the fading. By averaging over many network and shadowing realizations, the average outage probability and transmission capacity are computed. Using the analysis, many aspects of the network performance are illuminated. For example, one can determine the influence of the choice of spreading factors, the effect of the receiver location within the finite network region, and the impact of both the fading parameters and the attenuation power laws.
An Approach For Integration Testing In Online Retail Applications
Venue: arXiv cs.SE 2012
Year: 2012

Retail applications has majorly fraud prevention, procurement, shipping and tax related, pricing, real time bank authentication applications integrated to make the application run successfully. Integration testing here plays an important role as it requires that all applications interact with each other and also interact correctly so that Retailer is at benefit. Different testing techniques and types are used to test the application. Different testing teams will perform integration testing but what is the correct approach and how should you proceed is the major concern of many. Here we propose at what stage of Software Testing Life Cycle (STLC), integration testing should be initiated. Also what should be the approach of performing the testing? An example on Online Retail Application is used to understand the approach.
Quality assurance of e-learning processes
Venue: arXiv cs.CY 2012
Year: 2012

A quality assurance system (QA) should ensure that student needs are met. It also respects accreditation requirements and student perceptions, supports training and development of teaching staff, controls costs and improves efficiency of e-learning system.
Search Algorithms for Conceptual Graph Databases
Venue: arXiv cs.DS 2012
Year: 2012

We consider a database composed of a set of conceptual graphs. Using conceptual graphs and graph homomorphism it is possible to build a basic query-answering mechanism based on semantic search. Graph homomorphism defines a partial order over conceptual graphs. Since graph homomorphism checking is an NP-Complete problem, the main requirement for database organizing and managing algorithms is to reduce the number of homomorphism checks. Searching is a basic operation for database manipulating problems. We consider the problem of searching for an element in a partially ordered set. The goal is to minimize the number of queries required to find a target element in the worst case. First we analyse conceptual graph database operations. Then we propose a new algorithm for a subclass of lattices. Finally, we suggest a parallel search algorithm for a general poset. Keywords. Conceptual Graph, Graph Homomorphism, Partial Order, Lattice, Search, Database.
Enterprise Resource Planning - Real blessing or a Blessing in Disguise : An Exploration of the Contextual Factors in Public Sector
Venue: arXiv cs.CY 2012
Year: 2012

Information systems have always been in a prime focus in organizations in both local (Pakistani) and global environment. Now the race of being the best through Information Systems has created its importance in public sector organizations to meet the global challenges. Public sector organizations have been facing problems in different segments of technology adoption especially in ERP projects. ERP adoption/implementation projects in public sector organizations still encounter major setbacks in terms of partly/completely success/failure. Cultural and other social barriers have been resistant in technology adoption in Pakistan. Now in the case of big ERP adoptions the contextual factors must be identified and addressed. The paper investigates the reasons of success or failure by addressing nature of complexities regarding different contextual factors. The study includes a sample of Pakistan s four public sector organizations. The sample of this four organizations includes two organizations (Type-A) i.e. Oil & Gas Development Company Limited (OGDCL) and National Database Registration Authority (NADRA) where ERP has been successfully implemented and other two (Type-B) i.e. Pakistan Telecommunication Corporation Limited (PTCL), Higher Education Commission (HEC) where ERP implementation is in progress. The findings address the contextual factors i.e. cultural, environmental & political changes which have a variable impact on ERP systems adoption/implementation in addition to Business Process Re-engineering (BPR). Paper also briefly includes analysis of gaps between pre & post ERP implementation scenarios.
Design and Performance Analysis Of Ultra Low Power 6T SRAM Using Adiabatic Technique
Venue: arXiv cs.OH 2012
Year: 2012

Power consumption has become a critical concern in both high performance and portable applications. Methods for power reduction based on the application of adiabatic techniques to CMOS circuits have recently come under renewed investigation. In thermodynamics, an adiabatic energy transfer through a dissipative medium is one in which losses are made arbitrarily small by causing the transfer to occur sufficiently slowly. In this work adiabatic technique is used for reduction of average power dissipation. Simulation of 6T SRAM cell has been done for 180nm CMOS technology. It shows that average power dissipation is reduced up to 75% using adiabatic technique and also shows the effect on static noise margin.
Combining Brain-Computer Interfaces and Haptics: Detecting Mental Workload to Adapt Haptic Assistance
Venue: arXiv cs.GR 2012
Year: 2012

In this paper we introduce the combined use of Brain-Computer Interfaces (BCI) and Haptic interfaces. We propose to adapt haptic guides based on the mental activity measured by a BCI system. This novel approach is illustrated within a proof-of-concept system: haptic guides are toggled during a path-following task thanks to a mental workload index provided by a BCI. The aim of this system is to provide haptic assistance only when the user's brain activity reflects a high mental workload. A user study conducted with 8 participants shows that our proof-of-concept is operational and exploitable. Results show that activation of haptic guides occurs in the most difficult part of the path-following task. Moreover it allows to increase task performance by 53% by activating assistance only 59% of the time. Taken together, these results suggest that BCI could be used to determine when the user needs assistance during haptic interaction and to enable haptic guides accordingly.
Roadmap for Establishing Interoperability of Heterogeneous Cellular Network Technologies -1-
Venue: arXiv cs.NI 2012
Year: 2012

The lack of interoperability between cellular access networks has long been a challenging burden, which telecommunication engineers and researchers are trying to overcome. In second generation networks for example, this problem lies in the lack of standardization. 3rd G networks is limited to a few operating modes using different radio transmission technologies that are not interoperable. 4G technology even being successful in its various trials cannot guarantee interoperability. The undertaken approach to overcome this issue within heterogeneous networks begins by establishing a holistic understanding of cellular communication, and proposing an Ontological approach that expresses the domain's concepts, classes, and properties in a formal and unambiguous way. It begins by analyzing the structure of three different cellular technologies, and producing feature models. Lte-Advanced cellular network is the target of this ongoing analysis. The final objective sought is to build Ontology capable of providing a common view of cellular network technologies' domain.
Usability, Design and Content Issues of Mobile Apps for Cultural Heritage Promotion: The Malta Culture Guide Experience
Venue: arXiv cs.HC 2012
Year: 2012

The paper discusses the experience of producing and distributing an iPhone app for promotion of the Maltese Cultural Heritage on behalf of the Malta Tourism Authority. Thanks to its position at the heart of the Mediterranean Sea, Malta has been a crossroads of civilisations whose traces are still visible today, leaving a particularly rich and varied cultural heritage, from megalithic temples to baroque palaces and Caravaggio masterpieces. Conveying all these different aspects within a single application, using textual, visual, and audio means, has raised many different issues about the planning and production of cultural content for mobile usage, together with usability aspects regarding design and distribution of a mobile app. In this paper, we outline all of these aspects, focusing on the design and planning strategies for a long-term user commitment and how to evaluate results for cultural mobile applications. We include experience of all the steps of developing a mobile app, information that is of possible benefit to other app developers in the cultural sector.
Approximated Computation of Belief Functions for Robust Design Optimization
Venue: arXiv cs.CE 2012
Year: 2012

This paper presents some ideas to reduce the computational cost of evidence-based robust design optimization. Evidence Theory crystallizes both the aleatory and epistemic uncertainties in the design parameters, providing two quantitative measures, Belief and Plausibility, of the credibility of the computed value of the design budgets. The paper proposes some techniques to compute an approximation of Belief and Plausibility at a cost that is a fraction of the one required for an accurate calculation of the two values. Some simple test cases will show how the proposed techniques scale with the dimension of the problem. Finally a simple example of spacecraft system design is presented.
Infinite ternary square-free words concatenated from permutations of a single word
Venue: arXiv cs.FL 2012
Year: 2012

We answer a question of Harju: An infinite square-free ternary word with an $n$-stem factorization exists for any $n\ge 13$. We show that there are uniform ternary morphisms of length $k$ for every $k\ge 23$. This resolves almost completely a problem of the author and Rampersad.
Flux-splitting schemes for parabolic problems
Venue: arXiv cs.NA 2012
Year: 2012

To solve numerically boundary value problems for parabolic equations with mixed derivatives, the construction of difference schemes with prescribed quality faces essential difficulties. In parabolic problems, some possibilities are associated with the transition to a new formulation of the problem, where the fluxes (derivatives with respect to a spatial direction) are treated as unknown quantities. In this case, the original problem is rewritten in the form of a boundary value problem for the system of equations in the fluxes. This work deals with studying schemes with weights for parabolic equations written in the flux coordinates. Unconditionally stable flux locally one-dimensional schemes of the first and second order of approximation in time are constructed for parabolic equations without mixed derivatives. A peculiarity of the system of equations written in flux variables for equations with mixed derivatives is that there do exist coupled terms with time derivatives.
Analysis and Optimization of a Frequency-Hopping Ad Hoc Network in Rayleigh Fading
Venue: arXiv cs.IT 2012
Year: 2012

This paper proposes a new method for optimizing frequency-hopping ad hoc networks in the presence of Rayleigh fading. It is assumed that the system uses a capacity-approaching code (e.g., turbo or LDPC) and noncoherent binary continuous-phase frequency-shift keying (CPFSK) modulation. By using transmission capacity as the performance metric, the number of hopping channels, CPFSK modulation index, and code rate are jointly optimized. Mobiles in the network are assumed to be uniformly located within a finite area. Closed-form expressions for outage probability are given for a network characterized by a physical interference channel. The outage probability is first found conditioned on the locations of the mobiles, and then averaged over the spatial distribution of the mobiles. The transmission capacity, which is a measure of the spatial spectral efficiency, is obtained from the outage probability. The transmission capacity is modified to account for the constraints of the CPFSK modulation and capacity-approaching coding. Two optimization methods are proposed for maximizing the transmission capacity. The first is a brute-force method and the second is a gradient-search algorithm. The results obtained from the optimization shed new insight into the fundamental tradeoffs among the number of frequency-hopping channels, the modulation index, and the rate of the error-correcting code.