OpenRaiser/Intern-Atlas huggingface dataset:
P3: Toward Privacy-Preserving Photo Sharing
Venue: arXiv cs.CR 2013
Year: 2013

With increasing use of mobile devices, photo sharing services are experiencing greater popularity. Aside from providing storage, photo sharing services enable bandwidth-efficient downloads to mobile devices by performing server-side image transformations (resizing, cropping). On the flip side, photo sharing services have raised privacy concerns such as leakage of photos to unauthorized viewers and the use of algorithmic recognition technologies by providers. To address these concerns, we propose a privacy-preserving photo encoding algorithm that extracts and encrypts a small, but significant, component of the photo, while preserving the remainder in a public, standards-compatible, part. These two components can be separately stored. This technique significantly reduces the signal-to-noise ratio and the accuracy of automated detection and recognition on the public part, while preserving the ability of the provider to perform server-side transformations to conserve download bandwidth usage. Our prototype privacy-preserving photo sharing system, P3, works with Facebook, and can be extended to other services as well. P3 requires no changes to existing services or mobile application software, and adds minimal photo storage overhead.
Capturing Information Flows inside Android and Qemu Environments
Venue: arXiv cs.OS 2013
Year: 2013

The smartphone market has grown so wide that it assumed a strategic relevance. Today the most common smartphone OSs are Google's Android and Apple's iOS. The former is particularly interesting due to its open source nature, that allows everyone to deeply inspect every aspect of the OS. Android source code is also bundled with an hardware emulator, based on the open source software Qemu, that allows the user to run the Android OS without the need of a physical device. We first present a procedure to extract information flows from a generic system. We then focus on Android and Qemu architectures and their logging infrastructures. Finally, we detail what happens inside an Android device in a particular scenario: the system boot.
An efficient attack of a McEliece cryptosystem variant based on convolutional codes
Venue: arXiv cs.CR 2013
Year: 2013

Löndahl and Johansson proposed last year a variant of the McEliece cryptosystem which replaces Goppa codes by convolutional codes. This modification is supposed to make structural attacks more difficult since the public generator matrix of this scheme contains large parts which are generated completely at random. They proposed two schemes of this kind, one of them consists in taking a Goppa code and extending it by adding a generator matrix of a time varying convolutional code. We show here that this scheme can be successfully attacked by looking for low-weight codewords in the public code of this scheme and using it to unravel the convolutional part. It remains to break the Goppa part of this scheme which can be done in less than a day of computation in the case at hand.
Measuring Agglomeration of Agglomerated Particles Pictures
Venue: arXiv cs.CE 2013
Year: 2013

In this article, we introduce a novel geometrical index $δ_{agg}$, which is associated with the Euler number and is obtained by an image processing procedure for a given digital picture of aggregated particles such that $δ_{agg}$ exhibits the degree of the agglomerations of the particles. In the previous work (Matsutani, Shimosako, Wang, Appl.Math.Modeling {\bf{37}} (2013), 4007-4022), we proposed an algorithm to construct a picture of agglomerated particles as a Monte-Carlo simulation whose agglomeration degree is controlled by $γ_{agg} \in (0,1)$. By applying the image processing procedure to the pictures of the agglomeration particles constructed following the algorithm, we show that $δ_{agg}$ statistically reproduces the agglomeration parameter $γ_{agg}$.
Extensible Technology-Agnostic Runtime Verification
Venue: arXiv cs.SE 2013
Year: 2013

With numerous specialised technologies available to industry, it has become increasingly frequent for computer systems to be composed of heterogeneous components built over, and using, different technologies and languages. While this enables developers to use the appropriate technologies for specific contexts, it becomes more challenging to ensure the correctness of the overall system. In this paper we propose a framework to enable extensible technology agnostic runtime verification and we present an extension of polyLarva, a runtime-verification tool able to handle the monitoring of heterogeneous-component systems. The approach is then applied to a case study of a component-based artefact using different technologies, namely C and Java.
Critical Success Factors for Positive User Experience in Hotel Websites: Applying Herzberg's Two Factor Theory for User Experience Modeling
Venue: arXiv cs.CY 2013
Year: 2013

This research presents the development of a critical success factor matrix for increasing positive user experience of hotel websites based upon user ratings. Firstly, a number of critical success factors for web usability have been identified through the initial literature review. Secondly, hotel websites were surveyed in terms of critical success factors identified through the literature review. Thirdly, Herzberg's motivation theory has been applied to the user rating and the critical success factors were categorized into two areas. Finally, the critical success factor matrix has been developed using the two main sets of data.
A Proposal To Support Wellbeing in People With Borderline Personality Disorder: Applying Reminiscent Theory in a Mobile App
Venue: arXiv cs.CY 2013
Year: 2013

In this paper the research draws upon reminiscence therapy, which is used in treating dementia, as an applied theory to promote well being in people who experience low moods. The application proposed here aims to promote wellbeing for people suffering from mood disorders and dementia but could potentially be used to enhance wellbeing for many types of users. Use of the application is anticipated to improve mood in a group of users where severe emotional problems are prevalent. The research aims to evaluate the effectiveness of a reminiscence based application in promoting well being in people specifically with Borderline Personality Disorder (BPD). The long term objective of this research is to establish the effectiveness of reminiscence theory on user groups aside from dementia, particularly other mental illnesses. The research advocates involving end users within the design process both to inform and evaluate the development of a mobile and tablet application.
Development Of Ontology-Based Intelligent System For Software Testing
Venue: arXiv cs.AI 2013
Year: 2013

Software testing is a prime factor in software industry. Besides knowing the importance of testing, only limited time is allocated for teaching it. It will be more efficient if testing is taught simultaneously with programming foundations. This integrated learning of testing techniques and programming allows the programmers to perform in a better way and this leads to the improvement of the performance of the industry progress. In this paper, a technique named ontology is introduced, it first defines the various testing process in hierarchy and define relationships among them, to share and reuse the knowledge that is captured, secondly metadata is created by natural language processing and finally, the application use ontologies to support test management, it act as knowledge base for multiple environment with the integrated teaching of programming foundation and testing concepts. Keywords: Meta Data, Ontology, Software Testing, Integration, Programming Foundations.
Expressing Properties in Second and Third Order Logic: Hypercube Graphs and SATQBF
Venue: arXiv cs.LO 2013
Year: 2013

It follows from the famous Fagin's theorem that all problems in NP are expressible in existential second-order logic (ESO), and vice versa. Indeed, there are well-known ESO characterizations of NP-complete problems such as 3-colorability, Hamiltonicity and clique. Furthermore, the ESO sentences that characterize those problems are simple and elegant. However, there are also NP problems that do not seem to possess equally simple and elegant ESO characterizations. In this work, we are mainly interested in this latter class of problems. In particular, we characterize in second-order logic the class of hypercube graphs and the classes SATQBF_k of satisfiable quantified Boolean formulae with k alternations of quantifiers. We also provide detailed descriptions of the strategies followed to obtain the corresponding nontrivial second-order sentences. Finally, we sketch a third-order logic sentence that defines the class SATQBF = \bigcup_{k \geq 1} SATQBF_k. The sub-formulae used in the construction of these complex second- and third-order logic sentences, are good candidates to form part of a library of formulae. Same as libraries of frequently used functions simplify the writing of complex computer programs, a library of formulae could potentially simplify the writing of complex second- and third-order queries, minimizing the probability of error.
Dynamic Memory Allocation Policies for Postings in Real-Time Twitter Search
Venue: arXiv cs.IR 2013
Year: 2013

We explore a real-time Twitter search application where tweets are arriving at a rate of several thousands per second. Real-time search demands that they be indexed and searchable immediately, which leads to a number of implementation challenges. In this paper, we focus on one aspect: dynamic postings allocation policies for index structures that are completely held in main memory. The core issue can be characterized as a "Goldilocks Problem". Because memory remains today a scare resource, an allocation policy that is too aggressive leads to inefficient utilization, while a policy that is too conservative is slow and leads to fragmented postings lists. We present a dynamic postings allocation policy that allocates memory in increasingly-larger "slices" from a small number of large, fixed pools of memory. Through analytical models and experiments, we explore different settings that balance time (query evaluation speed) and space (memory utilization).
Non-Linear Distributed Average Consensus using Bounded Transmissions
Venue: arXiv cs.DC 2013
Year: 2013

A distributed average consensus algorithm in which every sensor transmits with bounded peak power is proposed. In the presence of communication noise, it is shown that the nodes reach consensus asymptotically to a finite random variable whose expectation is the desired sample average of the initial observations with a variance that depends on the step size of the algorithm and the variance of the communication noise. The asymptotic performance is characterized by deriving the asymptotic covariance matrix using results from stochastic approximation theory. It is shown that using bounded transmissions results in slower convergence compared to the linear consensus algorithm based on the Laplacian heuristic. Simulations corroborate our analytical findings.
Facilitating Machine to Machine (M2M) Communication using GSM Network
Venue: arXiv cs.IT 2013
Year: 2013

In this paper a method to facilitate M2M communication using existing GSM networks is proposed - as M2M devices primarily use SMS as their data bearer, the focus is on increasing the number of devices that can use the associated GSM signaling channels at a time. This is achieved by defining a new class of low mobility, static M2M devices which use a modified physical layer control frame structure. The proposal is expected to aid a quick, reliable and cost-effective deployment of M2M devices in the existing GSM networks.
Statistical Approach for Predicting Factors of Mood Method for Object Oriented
Venue: arXiv cs.SE 2013
Year: 2013

Object oriented design is becoming more popular in software development and object oriented design metrics which is an essential part of software environment. The main goal in this paper is to predict factors of MOOD method for OO using a statistical approach. Therefore, linear regression model is used to find the relationship between factors of MOOD method and their influences on OO software measurements. Fortunately, through this process a prediction could be made for the line of code (LOC), number of classes (NOC), number of methods (NOM), and number of attributes (NOA). These measurements permit designers to access the software early in process, making changes that will reduce complexity and improve the continuing capability of the design.
Implications for Improving Accessibility to E-Commerce Websites in Developing Countries - A Study of Hotel Websites
Venue: arXiv cs.HC 2013
Year: 2013

This research explores the accessibility issues with regard to the e-commerce websites in developing countries, through a study of Sri Lankan hotel websites. A web survey and a web content analysis were conducted as the methods to elicit data on web accessibility. Factors preventing accessibility were hypothesized as an initial experiment. Affecting design elements are identified through web content analysis, the results of which are utilized to develop specific implications for improving web accessibility. The hypothesis tests show that there is no significant correlation between accessibility and geographical or economic factors. However, physical impairments of users have a considerable influence on the accessibility of web page user interface if it has been designed without full consideration of the needs of all users. Especially, visual and mobility impaired users experience poor accessibility. Poor readability and less navigable page designs are two observable issues, which pose threats to accessibility. The lack of conformance to W3C accessibility guidelines and the poor design process are the specific shortcomings which reduce the overall accessibility. Guidelines aim to improve the accessibility of sites with a strategic focus. Further enhancements are suggested with adherence to principles, user centered design and developing customizable web portals compatible for connections with differing speeds. Re-ordering search results has been suggested as one of the finest step towards making the web content accessible for users with differing needs. A need for developing new design models for differencing user groups and implementing web accessibility strategy are emphasized as vital steps towards effective information dissemination via e-commerce websites in the developing countries.
HCI considerations in Designing a Second Life Virtual Therapeutic Community for the Support & Treatment of People with Borderline Personality Disorder
Venue: arXiv cs.HC 2013
Year: 2013

This paper aims to present the current position of the ongoing research into developing the requirements and acceptance of a virtual therapeutic community in Second Life, specifically for people with Borderline Personality Disorder (BPD). The research has identified this particular user group given that people with BPD often require high levels of support, which can result in emergency hospital admissions, in addition to the significant economic cost of treating people BPD in relation to other mental illnesses (NCCMH, 2009). The research is also intended to be used as framework for other mental health conditions. This work is a continuation of the research carried out in exploring the potential of virtual therapeutic communities based on existing models of therapeutic hospitals as well as virtual treatments and support, in treating people with BPD. An interdisciplinary approach to this research features collaboration from areas in HCI, forensic psychology and psychotherapy.
Transit Node Routing Reconsidered
Venue: arXiv cs.DS 2013
Year: 2013

Transit Node Routing (TNR) is a fast and exact distance oracle for road networks. We show several new results for TNR. First, we give a surprisingly simple implementation fully based on Contraction Hierarchies that speeds up preprocessing by an order of magnitude approaching the time for just finding a CH (which alone has two orders of magnitude larger query time). We also develop a very effective purely graph theoretical locality filter without any compromise in query times. Finally, we show that a specialization to the online many-to-one (or one-to-many) shortest path further speeds up query time by an order of magnitude. This variant even has better query time than the fastest known previous methods which need much more space.
Comments on "Resource placement in Cartesian product of networks" [Imani, Sarbazi-Azad and Zomaya, J. Parallel Distrib. Comput., 70 (2010) 481-495]
Venue: arXiv cs.DC 2013
Year: 2013

The present note points out a number of errors, omissions, redundancies and arbitrary deviations from the standard terminology in the paper "Resource placement in Cartesian product of networks," by N. Imani, H. Sarbazi-Azad and A.Y. Zomaya [J. Parallel Distrib. Comput. 70 (2010) 481-495].
Weighted Sets of Probabilities and Minimax Weighted Expected Regret: New Approaches for Representing Uncertainty and Making Decisions
Venue: arXiv cs.GT 2013
Year: 2013

We consider a setting where an agent's uncertainty is represented by a set of probability measures, rather than a single measure. Measure-by-measure updating of such a set of measures upon acquiring new information is well-known to suffer from problems; agents are not always able to learn appropriately. To deal with these problems, we propose using weighted sets of probabilities: a representation where each measure is associated with a weight, which denotes its significance. We describe a natural approach to updating in such a situation and a natural approach to determining the weights. We then show how this representation can be used in decision-making, by modifying a standard approach to decision making -- minimizing expected regret -- to obtain minimax weighted expected regret (MWER). We provide an axiomatization that characterizes preferences induced by MWER both in the static and dynamic case.
Prediction by Random-Walk Perturbation
Venue: arXiv cs.LG 2013
Year: 2013

We propose a version of the follow-the-perturbed-leader online prediction algorithm in which the cumulative losses are perturbed by independent symmetric random walks. The forecaster is shown to achieve an expected regret of the optimal order O(sqrt(n log N)) where n is the time horizon and N is the number of experts. More importantly, it is shown that the forecaster changes its prediction at most O(sqrt(n log N)) times, in expectation. We also extend the analysis to online combinatorial optimization and show that even in this more general setting, the forecaster rarely switches between experts while having a regret of near-optimal order.
A Piggybacking Design Framework for Read-and Download-efficient Distributed Storage Codes
Venue: arXiv cs.IT 2013
Year: 2013

We present a new 'piggybacking' framework for designing distributed storage codes that are efficient in data-read and download required during node-repair. We illustrate the power of this framework by constructing classes of explicit codes that entail the smallest data-read and download for repair among all existing solutions for three important settings: (a) codes meeting the constraints of being Maximum-Distance-Separable (MDS), high-rate and having a small number of substripes, arising out of practical considerations for implementation in data centers, (b) binary MDS codes for all parameters where binary MDS codes exist, (c) MDS codes with the smallest repair-locality. In addition, we employ this framework to enable efficient repair of parity nodes in existing codes that were originally constructed to address the repair of only the systematic nodes. The basic idea behind our framework is to take multiple instances of existing codes and add carefully designed functions of the data of one instance to the other. Typical savings in data-read during repair is 25% to 50% depending on the choice of the code parameters.
A Multi-Scale Spatial Model for RSS-based Device-Free Localization
Venue: arXiv cs.NI 2013
Year: 2013

RSS-based device-free localization (DFL) monitors changes in the received signal strength (RSS) measured by a network of static wireless nodes to locate people without requiring them to carry or wear any electronic device. Current models assume that the spatial impact area, i.e., the area in which a person affects a link's RSS, has constant size. This paper shows that the spatial impact area varies considerably for each link. Data from extensive experiments are used to derive a multi-scale spatial weight model that is a function of the fade level, i.e., the difference between the predicted and measured RSS, and of the direction of RSS change. In addition, a measurement model is proposed which gives a probability of a person locating inside the derived spatial model for each given RSS measurement. A real-time radio tomographic imaging system is described which uses channel diversity and the presented models. Experiments in an open indoor environment, in a typical one-bedroom apartment and in a through-wall scenario are conducted to determine the accuracy of the system. We demonstrate that the new system is capable of localizing and tracking a person with high accuracy (<0.30 m) in all the environments, without the need to change the model parameters.
Low-Complexity Variable Forgetting Factor Techniques for RLS Algorithms in Interference Rejection Applications
Venue: arXiv cs.IT 2013
Year: 2013

We propose a low-complexity variable forgetting factor (VFF) mechanism for recursive least square (RLS) algorithms in interference suppression applications. The proposed VFF mechanism employs an updated component related to the time average of the error correlation to automatically adjust the forgetting factor in order to ensure fast convergence and good tracking of the interference and the channel. Convergence and tracking analyses are carried out and analytical expressions for predicting the mean squared error of the proposed adaptation technique are obtained. Simulation results for a direct-sequence code-division multiple access (DS-CDMA) system are presented in nonstationary environments and show that the proposed VFF mechanism achieves superior performance to previously reported methods at a reduced complexity.
Limited Feedback Design for Interference Alignment on MIMO Interference Networks with Heterogeneous Path Loss and Spatial Correlations
Venue: arXiv cs.IT 2013
Year: 2013

Interference alignment is degree of freedom optimal in K -user MIMO interference channels and many previous works have studied the transceiver designs. However, these works predominantly focus on networks with perfect channel state information at the transmitters and symmetrical interference topology. In this paper, we consider a limited feedback system with heterogeneous path loss and spatial correlations, and investigate how the dynamics of the interference topology can be exploited to improve the feedback efficiency. We propose a novel spatial codebook design, and perform dynamic quantization via bit allocations to adapt to the asymmetry of the interference topology. We bound the system throughput under the proposed dynamic scheme in terms of the transmit SNR, feedback bits and the interference topology parameters. It is shown that when the number of feedback bits scales with SNR as C_{s}\cdot\log\textrm{SNR}, the sum degrees of freedom of the network are preserved. Moreover, the value of scaling coefficient C_{s} can be significantly reduced in networks with asymmetric interference topology.