OpenRaiser/Intern-Atlas huggingface dataset:
On the difference between checking integrity constraints before or after updates
Venue: arXiv cs.DB 2013
Year: 2013

Integrity checking is a crucial issue, as databases change their instance all the time and therefore need to be checked continuously and rapidly. Decades of research have produced a plethora of methods for checking integrity constraints of a database in an incremental manner. However, not much has been said about when to check integrity. In this paper, we study the differences and similarities between checking integrity before an update (a.k.a. pre-test) or after (a.k.a. post-test) in order to assess the respective convenience and properties.
Towards Ontological Support for Principle Solutions in Mechanical Engineering
Venue: arXiv cs.SE 2013
Year: 2013

The engineering design process follows a series of standardized stages of development, which have many aspects in common with software engineering. Among these stages, the principle solution can be regarded as an analogue of the design specification, fixing as it does the way the final product works. It is usually constructed as an abstract sketch (hand-drawn or constructed with a CAD system) where the functional parts of the product are identified, and geometric and topological constraints are formulated. Here, we outline a semantic approach where the principle solution is annotated with ontological assertions, thus making the intended requirements explicit and available for further machine processing; this includes the automated detection of design errors in the final CAD model, making additional use of a background ontology of engineering knowledge. We embed this approach into a document-oriented design workflow, in which the background ontology and semantic annotations in the documents are exploited to trace parts and requirements through the design process and across different applications.
Connectivity maintenance by robotic Mobile Ad-hoc NETwork
Venue: arXiv cs.RO 2013
Year: 2013

The problem of maintaining a wireless communication link between a fixed base station and an autonomous agent by means of a team of mobile robots is addressed in this work. Such problem can be of interest for search and rescue missions in post disaster scenario where the autonomous agent can be used for remote monitoring and first hand knowledge of the aftermath, while the mobile robots can be used to provide the agent the possibility to dynamically send its collected information to an external base station. To study the problem, a distributed multi-robot system with wifi communication capabilities has been developed and used to implement a Mobile Ad-hoc NETwork (MANET) to guarantee the required multi-hop communication. None of the robots of the team possess the knowledge of agent's movement, neither they hold a pre-assigned position in the ad-hoc network but they adapt with respect to the dynamic environmental situations. This adaptation only requires the robots to have the knowledge of their position and the possibility to exchange such information with their one-hop neighbours. Robots' motion is achieved by implementing a behavioural control, namely the Null-Space based Behavioural control, embedding the collective mission to achieve the required self-configuration. Validation of the approach is performed by means of demanding experimental tests involving five ground mobile robots capable of self localization and dynamic obstacle avoidance.
Sense, Model and Identify the Load Signatures of HVAC Systems in Metro Stations
Venue: arXiv cs.SY 2013
Year: 2013

The HVAC systems in subway stations are energy consuming giants, each of which may consume over 10, 000 Kilowatts per day for cooling and ventilation. To save energy for the HVAC systems, it is critically important to firstly know the "load signatures" of the HVAC system, i.e., the quantity of heat imported from the outdoor environments and by the passengers respectively in different periods of a day, which will significantly benefit the design of control policies. In this paper, we present a novel sensing and learning approach to identify the load signature of the HVAC system in the subway stations. In particular, sensors and smart meters were deployed to monitor the indoor, outdoor temperatures, and the energy consumptions of the HVAC system in real-time. The number of passengers was counted by the ticket checking system. At the same time, the cooling supply provided by the HVAC system was inferred via the energy consumption logs of the HVAC system. Since the indoor temperature variations are driven by the difference of the loads and the cooling supply, linear regression model was proposed for the load signature, whose coefficients are derived via a proposed algorithm . We collected real sensing data and energy log data from HaiDianHuangZhuang Subway station, which is in line 4 of Beijing from the duration of July 2012 to Sept. 2012. The data was used to evaluate the coefficients of the regression model. The experiment results show typical variation signatures of the loads from the passengers and from the outdoor environments respectively, which provide important contexts for smart control policies.
The Study about the Analysis of Responsiveness Pair Clustering to Social Network Bipartite Graph
Venue: arXiv cs.CY 2013
Year: 2013

In this study, regional (cities, towns and villages) data and tweet data are obtained from Twitter, and extract information of purchase information (Where and what bought) from the tweet data by morphological analysis and rule-based dependency analysis. Then, the "The regional information" and "The information of purchase history (Where and what bought information)" are captured as bipartite graph, and Responsiveness Pair Clustering analysis (a clustering using correspondence analysis as similarity measure) is conducted. In this study, since it was found to be difficult to analyze a network such as bipartite graph having limitations in links by using modularity Q, responsiveness is used instead of modularity Q as similarity measure. As a result of this analysis, "regional information cluster" which refers to similar "The information of purchase history" nodes group is generated. Finally, similar regions are visualized by mapping the regional information cluster on the map. This visualization system is expected to contribute as an analytical tool for customers purchasing behavior and so on.
From Lock Freedom to Progress Using Session Types
Venue: arXiv cs.PL 2013
Year: 2013

Inspired by Kobayashi's type system for lock freedom, we define a behavioral type system for ensuring progress in a language of binary sessions. The key idea is to annotate actions in session types with priorities representing the urgency with which such actions must be performed and to verify that processes perform such actions with the required priority. Compared to related systems for session-based languages, the presented type system is relatively simpler and establishes progress for a wider range of processes.
Coinductive Big-Step Semantics for Concurrency
Venue: arXiv cs.PL 2013
Year: 2013

In a paper presented at SOS 2010, we developed a framework for big-step semantics for interactive input-output in combination with divergence, based on coinductive and mixed inductive-coinductive notions of resumptions, evaluation and termination-sensitive weak bisimilarity. In contrast to standard inductively defined big-step semantics, this framework handles divergence properly; in particular, runs that produce some observable effects and then diverge, are not "lost". Here we scale this approach for shared-variable concurrency on a simple example language. We develop the metatheory of our semantics in a constructive logic.
OCEAN: Open-source Collation of eGovernment data And Networks - Understanding Privacy Leaks in Open Government Data
Venue: arXiv cs.CY 2013
Year: 2013

The awareness and sense of privacy has increased in the minds of people over the past few years. Earlier, people were not very restrictive in sharing their personal information, but now they are more cautious in sharing it with strangers, either in person or online. With such privacy expectations and attitude of people, it is difficult to embrace the fact that a lot of information is publicly available on the web. Information portals in the form of the e-governance websites run by Delhi Government in India provide access to such PII without any anonymization. Several databases e.g., Voterrolls, Driving Licence number, MTNL phone directory, PAN card serve as repositories of personal information of Delhi residents. This large amount of available personal information can be exploited due to the absence of proper written law on privacy in India. PII can also be collected from various social networking sites like Facebook, Twitter, GooglePlus etc. where the users share some information about them. Since users themselves put this information, it may not be considered as a privacy breach, but if the information is aggregated, it may give out much more information resulting in a bigger threat. To bring such issues to public notice, we developed Open-source Collation of eGovernment data And Networks (OCEAN), a system where the user enters little information (e.g. Name) about a person and gets large amount of personal information about him / her like name, age, address, date of birth, mother's name, father's name, voter ID, driving licence number, PAN.
Coverage, field specialization and impact of scientific publishers indexed in the 'Book Citation Index'
Venue: arXiv cs.DL 2013
Year: 2013

Purpose: The aim of this study is to analyze the disciplinary coverage of the Thomson Reuters' Book Citation Index database focusing on publisher presence, impact and specialization. Design/Methodology/approach: We conduct a descriptive study in which we examine coverage by discipline, publisher distribution by field and country of publication, and publisher impact. For this the Thomson Reuters' Subject Categories were aggregated into 15 disciplines. Findings: 30% of the total share of this database belongs to the fields of Humanities and Social Sciences. Most of the disciplines are covered by very few publishers mainly from the UK and USA (75.05% of the books), in fact 33 publishers concentrate 90% of the whole share. Regarding publisher impact, 80.5% of the books and chapters remained uncited. Two serious errors were found in this database. Firstly, the Book Citation Index does not retrieve all citations for books and chapters. Secondly, book citations do not include citations to their chapters. Research limitations/implications: The Book Citation Index is still underdeveloped and has serious limitations which call into caution when using it for bibliometric purposes. Practical implications: The results obtained from this study warn against the use of this database for bibliometric purposes, but opens a new window of opportunities for covering long neglected areas such as Humanities and Social Sciences. The target audience of this study is librarians, bibliometricians, researchers, scientific publishers, prospective authors and evaluation agencies. Originality/Value: There are currently no studies analyzing in depth the coverage of this novel database which covers monographs.
Reverberant Audio Source Separation via Sparse and Low-Rank Modeling
Venue: arXiv cs.SD 2013
Year: 2013

The performance of audio source separation from underdetermined convolutive mixture assuming known mixing filters can be significantly improved by using an analysis sparse prior optimized by a reweighting l1 scheme and a wideband datafidelity term, as demonstrated by a recent article. In this letter, we show that the performance can be improved even more significantly by exploiting a low-rank prior on the source spectrograms.We present a new algorithm to estimate the sources based on i) an analysis sparse prior, ii) a reweighting scheme so as to increase the sparsity, iii) a wideband data-fidelity term in a constrained form, and iv) a low-rank constraint on the source spectrograms. Evaluation on reverberant music mixtures shows that the resulting algorithm improves state-of-the-art methods by more than 2 dB of signal-to-distortion ratio.
A Novel Software Tool for Analysing NT File System Permissions
Venue: arXiv cs.SE 2013
Year: 2013

Administrating and monitoring New Technology File System (NTFS) permissions can be a cumbersome and convoluted task. In today's data rich world there has never been a more important time to ensure that data is secured against unwanted access. This paper identifies the essential and fundamental requirements of access control, highlighting the main causes of their misconfiguration within the NTFS. In response, a number of features are identified and an efficient, informative and intuitive software-based solution is proposed for examining file system permissions. In the first year that the software has been made freely available it has been downloaded and installed by over four thousand users
Predictive Comparative QSAR Analysis Of As 5-Nitofuran-2-YL Derivatives Myco bacterium tuberculosis H37RV Inhibitors Bacterium Tuberculosis H37RV Inhibitors
Venue: arXiv cs.CE 2013
Year: 2013

Antitubercular activity of 5-nitrofuran-2-yl Derivatives series were subjected to Quantitative Structure Activity Relationship (QSAR) Analysis with an effort to derive and understand a correlation between the biological activity as response variable and different molecular descriptors as independent variables. QSAR models are built using 40 molecular descriptor dataset. Different statistical regression expressions were got using Partial Least Squares (PLS),Multiple Linear Regression (MLR) and Principal Component Regression (PCR) techniques. The among these technique, Partial Least Square Regression (PLS) technique has shown very promising result as compared to MLR technique A QSAR model was build by a training set of 30 molecules with correlation coefficient ($r^2$) of 0.8484, significant cross validated correlation coefficient ($q^2$) is 0.0939, F test is 48.5187, ($r^2$) for external test set (pred$_r^2$) is -0.5604, coefficient of correlation of predicted data set (pred$_r^2se$) is 0.7252 and degree of freedom is 26 by Partial Least Squares Regression technique.
A Robust Missing Value Imputation Method MifImpute For Incomplete Molecular Descriptor Data And Comparative Analysis With Other Missing Value Imputation Methods
Venue: arXiv cs.CE 2013
Year: 2013

Missing data imputation is an important research topic in data mining. Large-scale Molecular descriptor data may contains missing values (MVs). However, some methods for downstream analyses, including some prediction tools, require a complete descriptor data matrix. We propose and evaluate an iterative imputation method MiFoImpute based on a random forest. By averaging over many unpruned regression trees, random forest intrinsically constitutes a multiple imputation scheme. Using the NRMSE and NMAE estimates of random forest, we are able to estimate the imputation error. Evaluation is performed on two molecular descriptor datasets generated from a diverse selection of pharmaceutical fields with artificially introduced missing values ranging from 10% to 30%. The experimental result demonstrates that missing values has a great impact on the effectiveness of imputation techniques and our method MiFoImpute is more robust to missing value than the other ten imputation methods used as benchmark. Additionally, MiFoImpute exhibits attractive computational efficiency and can cope with high-dimensional data.
Abridged Petri Nets
Venue: arXiv cs.OH 2013
Year: 2013

A new graphical framework, Abridged Petri Nets (APNs) is introduced for bottom-up modeling of complex stochastic systems. APNs are similar to Stochastic Petri Nets (SPNs) in as much as they both rely on component-based representation of system state space, in contrast to Markov chains that explicitly model the states of an entire system. In both frameworks, so-called tokens (denoted as small circles) represent individual entities comprising the system; however, SPN graphs contain two distinct types of nodes (called places and transitions) with transitions serving the purpose of routing tokens among places. As a result, a pair of place nodes in SPNs can be linked to each other only via a transient stop, a transition node. In contrast, APN graphs link place nodes directly by arcs (transitions), similar to state space diagrams for Markov chains, and separate transition nodes are not needed. Tokens in APN are distinct and have labels that can assume both discrete values ("colors") and continuous values ("ages"), both of which can change during simulation. Component interactions are modeled in APNs using triggers, which are either inhibitors or enablers (the inhibitors' opposites). Hierarchical construction of APNs rely on using stacks (layers) of submodels with automatically matching color policies. As a result, APNs provide at least the same modeling power as SPNs, but, as demonstrated by means of several examples, the resulting models are often more compact and transparent, therefore facilitating more efficient performance evaluation of complex systems.
Hardness of Finding Independent Sets in 2-Colorable Hypergraphs and of Satisfiable CSPs
Venue: arXiv cs.CC 2013
Year: 2013

This work revisits the PCP Verifiers used in the works of Hastad [Has01], Guruswami et al.[GHS02], Holmerin[Hol02] and Guruswami[Gur00] for satisfiable Max-E3-SAT and Max-Ek-Set-Splitting, and independent set in 2-colorable 4-uniform hypergraphs. We provide simpler and more efficient PCP Verifiers to prove the following improved hardness results: Assuming that NP\not\subseteq DTIME(N^{O(loglog N)}), There is no polynomial time algorithm that, given an n-vertex 2-colorable 4-uniform hypergraph, finds an independent set of n/(log n)^c vertices, for some constant c > 0. There is no polynomial time algorithm that satisfies 7/8 + 1/(log n)^c fraction of the clauses of a satisfiable Max-E3-SAT instance of size n, for some constant c > 0. For any fixed k >= 4, there is no polynomial time algorithm that finds a partition splitting (1 - 2^{-k+1}) + 1/(log n)^c fraction of the k-sets of a satisfiable Max-Ek-Set-Splitting instance of size n, for some constant c > 0. Our hardness factor for independent set in 2-colorable 4-uniform hypergraphs is an exponential improvement over the previous results of Guruswami et al.[GHS02] and Holmerin[Hol02]. Similarly, our inapproximability of (log n)^{-c} beyond the random assignment threshold for Max-E3-SAT and Max-Ek-Set-Splitting is an exponential improvement over the previous bounds proved in [Has01], [Hol02] and [Gur00]. The PCP Verifiers used in our results avoid the use of a variable bias parameter used in previous works, which leads to the improved hardness thresholds in addition to simplifying the analysis substantially. Apart from standard techniques from Fourier Analysis, for the first mentioned result we use a mixing estimate of Markov Chains based on uniform reverse hypercontractivity over general product spaces from the work of Mossel et al.[MOS13].
A Survey of Network-On-Chip Tools
Venue: arXiv cs.AR 2013
Year: 2013

Nowadays System-On-Chips (SoCs) have evolved considerably in term of performances, reliability and integration capacity. The last advantage has induced the growth of the number of cores or Intellectual Properties (IPs) in a same chip. Unfortunately, this important number of IPs has caused a new issue which is the intra-communication between the elements of a same chip. To resolve this problem, a new paradigm has been introduced which is the Network-On-Chip (NoC). Since the introduction of the NoC paradigm in the last decade, new methodologies and approaches have been presented by research community and many of them have been adopted by industrials. The literature contains many relevant studies and surveys discussing NoC proposals and contributions. However, few of them have discussed or proposed a comparative study of NoC tools. The objective of this work is to establish a reliable survey about available design, simulation or implementation NoC tools. We collected an important amount of information and characteristics about NoC dedicated tools that we will present throughout this survey. This study is built around a respectable amount of references and we hope it will help scientists.
An Efficient Clustering Algorithm for Device-to-Device Assisted Virtual MIMO
Venue: arXiv cs.IT 2013
Year: 2013

In this paper, the utilization of mobile devices (MDs) as decode-and-forward relays in a device-to-device assisted virtual MIMO (VMIMO) system is studied. Single antenna MDs are randomly distributed on a 2D plane according to a Poisson point process, and only a subset of them are sources leaving other idle MDs available to assist them (relays). Our goal is to develop an efficient algorithm to cluster each source with a subset of available relays to form a VMIMO system under a limited feedback assumption. We first show that the NP- hard optimization problem of precoding in our scenario can be approximately solved by semidefinite relaxation. We investigate a special case with a single source and analytically derive an upper bound on the average spectral efficiency of the VMIMO system. Then, we propose an optimal greedy algorithm that achieves this bound. We further exploit these results to obtain a polynomial time clustering algorithm for the general case with multiple sources. Finally, numerical simulations are performed to compare the performance of our algorithm with that of an exhaustive clustering algorithm, and it shown that these numerical results corroborate the efficiency of our algorithm.
An Auction-driven Self-organizing Cloud Delivery Model
Venue: arXiv cs.DC 2013
Year: 2013

The three traditional cloud delivery models -- IaaS, PaaS, and SaaS -- constrain access to cloud resources by hiding their raw functionality and forcing us to use them indirectly via a restricted set of actions. Can we introduce a new delivery model, and, at the same time, support improved security, a higher degree of assurance, find relatively simple solutions to the hard cloud resource management problems, eliminate some of the inefficiencies related to resource virtualization, allow the assembly of clouds of clouds, and, last but not least, minimize the number of interoperability standards? We sketch a self-organizing architecture for very large compute clouds composed of many-core processors and heterogeneous coprocessors. We discuss how self-organization will address each of the challenges described above. The approach is {\em bid-centric}. The system of heterogeneous cloud resources is dynamically, and autonomically, configured to bid to meet the needs identified in a high-level task or service specification. When the task is completed, or the service is retired, the resources are released for subsequent reuse. Our approach mimics the process followed by individual researchers who, in response to a call for proposals released by a funding agency, organize themselves in groups of various sizes and specialities. If the bid is successful, then the group carries out the proposed work and releases the results. After the work is completed, individual researchers in the group disperse, possibly joining other groups or submitting individual bids in response to other proposals. Similar protocols are common to other human activities such as procurement management.