OpenRaiser/Intern-Atlas huggingface dataset:
Visual Noise from Natural Scene Statistics Reveals Human Scene Category Representations
Venue: arXiv cs.CV 2014
Year: 2014

Our perceptions are guided both by the bottom-up information entering our eyes, as well as our top-down expectations of what we will see. Although bottom-up visual processing has been extensively studied, comparatively little is known about top-down signals. Here, we describe REVEAL (Representations Envisioned Via Evolutionary ALgorithm), a method for visualizing an observer's internal representation of a complex, real-world scene, allowing us to, for the first time, visualize the top-down information in an observer's mind. REVEAL rests on two innovations for solving this high dimensional problem: visual noise that samples from natural image statistics, and a computer algorithm that collaborates with human observers to efficiently obtain a solution. In this work, we visualize observers' internal representations of a visual scene category (street) using an experiment in which the observer views the naturalistic visual noise and collaborates with the algorithm to externalize his internal representation. As no scene information was presented, observers had to use their internal knowledge of the target, matching it with the visual features in the noise. We matched reconstructed images with images of real-world street scenes to enhance visualization. Critically, we show that the visualized mental images can be used to predict rapid scene detection performance, as each observer had faster and more accurate responses to detecting real-world images that were the most similar to his reconstructed street templates. These results show that it is possible to visualize previously unobservable mental representations of real world stimuli. More broadly, REVEAL provides a general method for objectively examining the content of previously private, subjective mental experiences.
Identifying Cheating Anchor Nodes using Maximum Likelihood and Mahalanobis Distance
Venue: arXiv cs.CR 2014
Year: 2014

Malicious anchor nodes will constantly hinder genuine and appropriate localization. Discovering the malicious or vulnerable anchor node is an essential problem in Wireless Sensor Networks (WSNs). In wireless sensor networks, anchor nodes are the nodes that know its current location. Neighbouring nodes or non-anchor nodes calculate its location (or its location reference) with the help of anchor nodes. Ingenuous localization is not possible in the presence of a cheating anchor node or a cheating node. Nowadays, it's a challenging task to identify the cheating anchor node or cheating node in a network. Even after finding out the location of the cheating anchor node, there is no assurance, that the identified node is legitimate or not. This paper aims to localize the cheating anchor nodes using trilateration algorithm and later associate it with maximum likelihood expectation technique (MLE), and Mahalanobis distance to obtain maximum accuracy in identifying malicious or cheating anchor nodes during localization. We were able to attain a considerable reduction in the error achieved during localization. For implementation purpose we simulated our scheme using ns-3 network simulator.
Learning Based Frequency- and Time-Domain Inter-Cell Interference Coordination in HetNets
Venue: arXiv cs.NI 2014
Year: 2014

In this article, we focus on inter-cell interference coordination (ICIC) techniques in heterogeneous network (Het-Net) deployments, whereby macro- and picocells autonomously optimize their downlink transmissions, with loose coordination. We model this strategic coexistence as a multi-agent system, aiming at joint interference management and cell association. Using tools from Reinforcement Learning (RL), agents (i.e., macro- and picocells) sense their environment, and self-adapt based on local information so as to maximize their network performance. Specifically, we explore both time- and frequency domain ICIC scenarios, and propose a two-level RL formulation. Here, picocells learn their optimal cell range expansion (CRE) bias and transmit power allocation, as well as appropriate frequency bands for multi-flow transmissions, in which a user equipment (UE) can be simultaneously served by two or more base stations (BSs) from macro- and pico-layers. To substantiate our theoretical findings, Long Term Evolution Advanced (LTEA) based system level simulations are carried out in which our proposed approaches are compared with a number of baseline approaches, such as resource partitioning (RP), static CRE, and single-flow Carrier Aggregation (CA). Our proposed solutions yield substantial gains up to 125% compared to static ICIC approaches in terms of average UE throughput in the timedomain. In the frequency-domain our proposed solutions yield gains up to 240% in terms of cell-edge UE throughput.
Linking GloVe with word2vec
Venue: arXiv cs.CL 2014
Year: 2014

The Global Vectors for word representation (GloVe), introduced by Jeffrey Pennington et al. is reported to be an efficient and effective method for learning vector representations of words. State-of-the-art performance is also provided by skip-gram with negative-sampling (SGNS) implemented in the word2vec tool. In this note, we explain the similarities between the training objectives of the two models, and show that the objective of SGNS is similar to the objective of a specialized form of GloVe, though their cost functions are defined differently.
The Online Disjoint Set Cover Problem and its Applications
Venue: arXiv cs.DS 2014
Year: 2014

Given a universe $U$ of $n$ elements and a collection of subsets $\mathcal{S}$ of $U$, the maximum disjoint set cover problem (DSCP) is to partition $\mathcal{S}$ into as many set covers as possible, where a set cover is defined as a collection of subsets whose union is $U$. We consider the online DSCP, in which the subsets arrive one by one (possibly in an order chosen by an adversary), and must be irrevocably assigned to some partition on arrival with the objective of minimizing the competitive ratio. The competitive ratio of an online DSCP algorithm $A$ is defined as the maximum ratio of the number of disjoint set covers obtained by the optimal offline algorithm to the number of disjoint set covers obtained by $A$ across all inputs. We propose an online algorithm for solving the DSCP with competitive ratio $\ln n$. We then show a lower bound of $Ω(\sqrt{\ln n})$ on the competitive ratio for any online DSCP algorithm. The online disjoint set cover problem has wide ranging applications in practice, including the online crowd-sourcing problem, the online coverage lifetime maximization problem in wireless sensor networks, and in online resource allocation problems.
TrackMania is NP-complete
Venue: arXiv cs.CC 2014
Year: 2014

We prove that completing an untimed, unbounded track in TrackMania Nations Forever is NP-complete by using a reduction from 3-SAT and showing that a solution can be checked in polynomial time.
QoS-distinguished Achievable Rate Region for High Speed Railway Wireless Communications
Venue: arXiv cs.IT 2014
Year: 2014

In high speed railways (HSRs) communication system, when a train travels along the railway with high velocity, the wireless channel between the train and base station varies strenuously, which makes it essential to implement appropriate power allocations to guarantee system performance. What's more, how to evaluate the performance limits in this new scenario is also needed to consider. To this end, this paper investigates the performance limits of wireless communication in HSRs scenario. Since the hybrid information transmitted between train and base station usually has diverse quality of service (QoS) requirements, QoS-based achievable rate region is utilized to characterize the transmission performance in this paper. It is proved that traditional ergodic capacity and outage capacity with unique QoS requirement can be regarded as two extreme cases of the achievable rate region proposed in this paper. The corresponding optimal power allocation strategy is also given to achieve the maximal boundary of achievable rate region. Compared with conventional strategies, the advantages of the proposed strategy are validated in terms of green communication, namely minimizing average transmit power. Besides, the hybrid information transmission in a non-uniform generalized motion scenario is analyzed to confirm the robust performance of proposed strategy. The performance loss caused by non-uniform motion compared with that in uniform motion is also indicated, where a deterministic worst case for instantaneous speed realization is proposed to serve as the lower bound for system performance.
Pre-processing of Domain Ontology Graph Generation System in Punjabi
Venue: arXiv cs.CL 2014
Year: 2014

This paper describes pre-processing phase of ontology graph generation system from Punjabi text documents of different domains. This research paper focuses on pre-processing of Punjabi text documents. Pre-processing is structured representation of the input text. Pre-processing of ontology graph generation includes allowing input restrictions to the text, removal of special symbols and punctuation marks, removal of duplicate terms, removal of stop words, extract terms by matching input terms with dictionary and gazetteer lists terms.
On the Classification of MDS Codes
Venue: arXiv cs.IT 2014
Year: 2014

A $q$-ary code of length $n$, size $M$, and minimum distance $d$ is called an $(n,M,d)_q$ code. An $(n,q^{k},n-k+1)_q$ code is called a maximum distance separable (MDS) code. In this work, some MDS codes over small alphabets are classified. It is shown that every $(k+d-1,q^k,d)_q$ code with $k\geq 3$, $d \geq 3$, $q \in \{5,7\}$ is equivalent to a linear code with the same parameters. This implies that the $(6,5^4,3)_5$ code and the $(n,7^{n-2},3)_7$ MDS codes for $n\in\{6,7,8\}$ are unique. The classification of one-error-correcting $8$-ary MDS codes is also finished; there are $14$, $8$, $4$, and $4$ equivalence classes of $(n,8^{n-2},3)_8$ codes for $n=6,7,8,9$, respectively. One of the equivalence classes of perfect $(9,8^7,3)_8$ codes corresponds to the Hamming code and the other three are nonlinear codes for which there exists no previously known construction.
Joint Beamforming Optimization and Power Control for Full-Duplex MIMO Two-way Relay Channel
Venue: arXiv cs.IT 2014
Year: 2014

In this paper we explore the use of full-duplex radio to improve the spectrum efficiency in a two-way relay channel where two sources exchange information through an multi-antenna relay, and all nodes work in the full-duplex mode. The full-duplex operation can reduce the overall communication to only one phase but suffers from the self-interference. Instead of purely suppressing the self-interference, we aim to maximize the end-to-end performance by jointly optimizing the beamforming matrix at the relay which uses the amplify-and-forward protocol as well as the power control at the sources. To be specific, we propose iterative algorithms and 1-D search to solve two problems: finding the achievable rate region and maximizing the sum rate. At each iteration, either the analytical solution or convex formulation is obtained. We compare the proposed full-duplex two-way relaying with the conventional half-duplex two-way relaying, a full-duplex one-way relaying and a performance upper bound. Numerical results show that the proposed full-duplex scheme significantly improves the achievable data rates over the conventional scheme.
Distributed Power Control in Multiuser MIMO Networks with Optimal Linear Precoding
Venue: arXiv cs.IT 2014
Year: 2014

Contractive interference functions introduced by Feyzmahdavian et al. is the newest approach in the analysis and design of distributed power control laws. This approach can be extended to several cases of distributed power control. One of the distributed power control scenarios wherein the contractive interference functions have not been employed is the power control in MIMO systems. In this paper, this scenario will be analyzed. In addition, the optimal linear precoder is employed in each user to achieve maximum point-to-point information rate. In our approach, we use the same amount of signaling as the previous methods did. However, we show that the uniqueness of Nash equilibria is more probable in our approach, suggesting that our proposed method improves the convergence performance of distributed power control in MIMO systems. We also show that the proposed power control algorithm can be implemented asynchronously, which gives a noticeable flexibility to our algorithm given the practical communication limitations.
Identifying Talented Software Engineering Students through Data-driven Skill Assessment
Venue: arXiv cs.SE 2014
Year: 2014

For software development companies, one of the most important objectives is to identify and acquire talented software engineers in order to maintain a skilled team that can produce competitive products. Traditional approaches for finding talented young software engineers are mainly through programming contests of various forms which mostly test participants' programming skills. However, successful software engineering in practice requires a wider range of skills from team members including analysis, design, programming, testing, communication, collaboration, and self-management, etc. In this paper, we explore potential ways to identify talented software engineering students in a data-driven manner through an Agile Project Management (APM) platform. Through our proposed HASE online APM tool, we conducted a study involving 21 Scrum teams consisting of over 100 undergraduate software engineering students in multi-week coursework projects in 2014. During this study, students performed over 10,000 ASD activities logged by HASE. We demonstrate the possibility and potentials of this new research direction, and discuss its implications for software engineering education and industry recruitment.
Discrete Bayesian Networks: The Exact Posterior Marginal Distributions
Venue: arXiv cs.AI 2014
Year: 2014

In a Bayesian network, we wish to evaluate the marginal probability of a query variable, which may be conditioned on the observed values of some evidence variables. Here we first present our "border algorithm," which converts a BN into a directed chain. For the polytrees, we then present in details, with some modifications and within the border algorithm framework, the "revised polytree algorithm" by Peot & Shachter (1991). Finally, we present our "parentless polytree method," which, coupled with the border algorithm, converts any Bayesian network into a polytree, rendering the complexity of our inferences independent of the size of network, and linear with the number of its evidence and query variables. All quantities in this paper have probabilistic interpretations.
Hardware Counted Profile-Guided Optimization
Venue: arXiv cs.PL 2014
Year: 2014

Profile-Guided Optimization (PGO) is an excellent means to improve the performance of a compiled program. Indeed, the execution path data it provides helps the compiler to generate better code and better cacheline packing. At the time of this writing, compilers only support instrumentation-based PGO. This proved effective for optimizing programs. However, few projects use it, due to its complicated dual-compilation model and its high overhead. Our solution of sampling Hardware Performance Counters overcome these drawbacks. In this paper, we propose a PGO solution for GCC by sampling Last Branch Record (LBR) events and using debug symbols to recreate source locations of binary instructions. By using LBR-Sampling, the generated profiles are very accurate. This solution achieved an average of 83% of the gains obtained with instrumentation-based PGO and 93% on C++ benchmarks only. The profiling overhead is only 1.06% on average whereas instrumentation incurs a 16% overhead on average.
On the mathematic modeling of non-parametric curves based on cubic Bézier curves
Venue: arXiv cs.CV 2014
Year: 2014

Bézier splines are widely available in various systems with the curves and surface designs. In general, the Bézier spline can be specified with the Bézier curve segments and a Bézier curve segment can be fitted to any number of control points. The number of control points determines the degree of the Bézier polynomial. This paper presents a method which determines control points for Bézier curves approximating segments of obtained image outline(non-parametric curve) by using the properties of cubic Bézier curves. Proposed method is a technique to determine the control points that has generality and reduces the error of the Bézier curve approximation. Main advantage of proposed method is that it has higher accuracy and compression rate than previous methods. The cubic Bézier spline is obtained from cubic Bézier curve segments. To demonstrate the various performances of the proposed algorithm, experimental results are compared.
Sorting Networks: the End Game
Venue: arXiv cs.DS 2014
Year: 2014

This paper studies properties of the back end of a sorting network and illustrates the utility of these in the search for networks of optimal size or depth. All previous works focus on properties of the front end of networks and on how to apply these to break symmetries in the search. The new properties help shed understanding on how sorting networks sort and speed-up solvers for both optimal size and depth by an order of magnitude.
Deletion codes in the high-noise and high-rate regimes
Venue: arXiv cs.IT 2014
Year: 2014

The noise model of deletions poses significant challenges in coding theory, with basic questions like the capacity of the binary deletion channel still being open. In this paper, we study the harder model of worst-case deletions, with a focus on constructing efficiently decodable codes for the two extreme regimes of high-noise and high-rate. Specifically, we construct polynomial-time decodable codes with the following trade-offs (for any eps > 0): (1) Codes that can correct a fraction 1-eps of deletions with rate poly(eps) over an alphabet of size poly(1/eps); (2) Binary codes of rate 1-O~(sqrt(eps)) that can correct a fraction eps of deletions; and (3) Binary codes that can be list decoded from a fraction (1/2-eps) of deletions with rate poly(eps) Our work is the first to achieve the qualitative goals of correcting a deletion fraction approaching 1 over bounded alphabets, and correcting a constant fraction of bit deletions with rate aproaching 1. The above results bring our understanding of deletion code constructions in these regimes to a similar level as worst-case errors.
Detecting fraudulent activity in a cloud using privacy-friendly data aggregates
Venue: arXiv cs.CR 2014
Year: 2014

More users and companies make use of cloud services every day. They all expect a perfect performance and any issue to remain transparent to them. This last statement is very challenging to perform. A user's activities in our cloud can affect the overall performance of our servers, having an impact on other resources. We can consider these kind of activities as fraudulent. They can be either illegal activities, such as launching a DDoS attack or just activities which are undesired by the cloud provider, such as Bitcoin mining, which uses substantial power, reduces the life of the hardware and can possibly slow down other user's activities. This article discusses a method to detect such activities by using non-intrusive, privacy-friendly data: billing data. We use OpenStack as an example with data provided by Telemetry, the component in charge of measuring resource usage for billing purposes. Results will be shown proving the efficiency of this method and ways to improve it will be provided as well as its advantages and disadvantages.
Securing the Data in Clouds with Hyperelliptic Curve Cryptography
Venue: arXiv cs.CR 2014
Year: 2014

In todays world, Cloud computing has attracted research communities as it provides services in reduced cost due to virtualizing all the necessary resources. Even modern business architecture depends upon Cloud computing .As it is a internet based utility, which provides various services over a network, it is prone to network based attacks. Hence security in clouds is the most important in case of cloud computing. Cloud Security concerns the customer to fully rely on storing data on clouds. That is why Cloud security has attracted attention of the research community. This paper will discuss securing the data in clouds by implementing key agreement, encryption and signature verification/generation with hyperelliptic curve cryptography.
Efficient Fuzzy Search Engine with B-Tree Search Mechanism
Venue: arXiv cs.IR 2014
Year: 2014

Search engines play a vital role in day to day life on internet. People use search engines to find content on internet. Cloud computing is the computing concept in which data is stored and accessed with the help of a third party server called as cloud. Data is not stored locally on our machines and the softwares and information are provided to user if user demands for it. Search queries are the most important part in searching data on internet. A search query consists of one or more than one keywords. A search query is searched from the database for exact match, and the traditional searchable schemes do not tolerate minor typos and format inconsistencies, which happen quite frequently. This drawback makes the existing techniques unsuitable and they offer very low efficiency. In this paper, we will for the first time formulate the problem of effective fuzzy search by introducing tree search methodologies. We will explore the benefits of B trees in search mechanism and use them to have an efficient keyword search. We have taken into consideration the security analysis strictly so as to get a secure and privacy-preserving system.
Addressing NameNode Scalability Issue in Hadoop Distributed File System using Cache Approach
Venue: arXiv cs.DC 2014
Year: 2014

Hadoop is a distributed batch processing infrastructure which is currently being used for big data management. The foundation of Hadoop consists of Hadoop Distributed File System or HDFS. HDFS presents a client server architecture comprised of a NameNode and many DataNodes. The NameNode stores the metadata for the DataNodes and DataNode stores application data. The NameNode holds file system metadata in memory, and thus the limit to the number of files in a file system is governed by the amount of memory on the NameNode. Thus when the memory on NameNode is full there is no further chance of increasing the cluster capacity. In this paper we have used the concept of cache memory for handling the issue of NameNode scalability. The focus of this paper is to highlight our approach that tries to enhance the current architecture and ensure that NameNode does not reach its threshold value soon.
Some Reflections on the Set-based and the Conditional-based Interpretations of Statements in Syllogistic Reasoning
Venue: arXiv cs.AI 2014
Year: 2014

Two interpretations about syllogistic statements are described in this paper. One is the so-called set-based interpretation, which assumes that quantified statements and syllogisms talk about quantity-relationships between sets. The other one, the so-called conditional interpretation, assumes that quantified propositions talk about conditional propositions and how strong are the links between the antecedent and the consequent. Both interpretations are compared attending to three different questions (existential import, singular statements and non-proportional quantifiers) from the point of view of their impact on the further development of this type of reasoning.
Similarity- based approach for outlier detection
Venue: arXiv cs.CV 2014
Year: 2014

This paper presents a new approach for detecting outliers by introducing the notion of object's proximity. The main idea is that normal point has similar characteristics with several neighbors. So the point in not an outlier if it has a high degree of proximity and its neighbors are several. The performance of this approach is illustrated through real datasets