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Full-Text Articles in Physical Sciences and Mathematics

Computing Immutable Regions For Subspace Top-K Queries, Kyriakos Mouratidis, Hwee Hwa Pang Dec 2012

Computing Immutable Regions For Subspace Top-K Queries, Kyriakos Mouratidis, Hwee Hwa Pang

Kyriakos MOURATIDIS

Given a high-dimensional dataset, a top-k query can be used to shortlist the k tuples that best match the user’s preferences. Typically, these preferences regard a subset of the available dimensions (i.e., attributes) whose relative significance is expressed by user-specified weights. Along with the query result, we propose to compute for each involved dimension the maximal deviation to the corresponding weight for which the query result remains valid. The derived weight ranges, called immutable regions, are useful for performing sensitivity analysis, for finetuning the query weights, etc. In this paper, we focus on top-k queries with linear preference functions over …


When Would This Bug Get Reported?, Ferdian Thung, David Lo, Lingxiao Jiang, Lucia Lucia, Foyzur Rahman, Premkumar Devanbu Dec 2012

When Would This Bug Get Reported?, Ferdian Thung, David Lo, Lingxiao Jiang, Lucia Lucia, Foyzur Rahman, Premkumar Devanbu

David LO

Millions of people, including those in the software engineering communities have turned to microblogging services, such as Twitter, as a means to quickly disseminate information. A number of past studies by Treude et al., Storey, and Yuan et al. have shown that a wealth of interesting information is stored in these microblogs. However, microblogs also contain a large amount of noisy content that are less relevant to software developers in engineering software systems. In this work, we perform a preliminary study to investigate the feasibility of automatic classification of microblogs into two categories: relevant and irrelevant to engineering software systems. …


An Empirical Study Of Bugs In Machine Learning Systems, Ferdian Thung, Shaowei Wang, David Lo, Lingxiao Jiang Dec 2012

An Empirical Study Of Bugs In Machine Learning Systems, Ferdian Thung, Shaowei Wang, David Lo, Lingxiao Jiang

David LO

Many machine learning systems that include various data mining, information retrieval, and natural language processing code and libraries have being used in real world applications. Search engines, internet advertising systems, product recommendation systems are sample users of these algorithm intensive code and libraries. Machine learning code and toolkits have also been used in many recent studies on software mining and analytics that aim to automate various software engineering tasks. With the increasing number of important applications of machine learning systems, the reliability of such systems is also becoming increasingly important. A necessary step for ensuring reliability of such systems is …


Ict For Poverty Alleviation In Pacific Island Nations: Study Of Icts4d In Fiji, Deogratias Harorimana, Opeti Rokotuinivono, Emali Sewale, Fane Salaiwai, Marica Naulu, Evangelin Roy Dec 2012

Ict For Poverty Alleviation In Pacific Island Nations: Study Of Icts4d In Fiji, Deogratias Harorimana, Opeti Rokotuinivono, Emali Sewale, Fane Salaiwai, Marica Naulu, Evangelin Roy

Dr Deogratias Harorimana

ICT for Poverty Alleviation in Pacific Island Nations: Study of ICTs4D in Fiji There has been a vague and little knowledge on the role or potential of Information and Communications Technologies (ICTs) in relation to addressing poverty in Fiji. This may be probably due to the newness of the technology in the South Pacific Region as a whole but also probably due to the fact that only 9.7% of the current Fiji 931,000 populations are internet users (ITC Figures 2011). This paper reports on finding how ICTs is contributing towards poverty alleviation in Fiji. On the basis of reviewed best …


Tteleconsultation Technology And Its Benefits: In The Case Of Public Hospitals In Malaysia, Nurazean Maarop, Sukdershan Hazara Singh, Khin Than Win Dec 2012

Tteleconsultation Technology And Its Benefits: In The Case Of Public Hospitals In Malaysia, Nurazean Maarop, Sukdershan Hazara Singh, Khin Than Win

Dr Khin Win

The ultimate objectives of this study are to describe teleconsultation activities and explore the benefits of teleconsultation technology in the context of public health care environment in Malaysia. The materials of this study were based on an exploratory mixed method studies involving semi-structured interviews with key informants and questionnaires survey of health care providers to obtain information about existing teleconsultation activities as well as to uncover the benefits of teleconsultation technology. The notable benefits from teleconsultation implementation were further discussed. The findings confirmed that teleconsultation service has improved health care delivery in the underserved areas to consult with specialist. One …


Optimal Error Of Query Sets Under The Differentially-Private Matrix Mechanism, Chao Li, Gerome Miklau Dec 2012

Optimal Error Of Query Sets Under The Differentially-Private Matrix Mechanism, Chao Li, Gerome Miklau

Gerome Miklau

A common goal of privacy research is to release synthetic data that satisfies a formal privacy guarantee and can be used by an analyst in place of the original data. To achieve reasonable accuracy, a synthetic data set must be tuned to support a specified set of queries accurately, sacrificing fidelity for other queries.

This work considers methods for producing synthetic data under differential privacy and investigates what makes a set of queries "easy" or "hard" to answer. We consider answering sets of linear counting queries using the matrix mechanism, a recent differentially-private mechanism that can reduce error by adding …


Simulations In 3d Tactics, Interdiction And Multi-Agent Modelling, A. R. Green, I. C. Piper, Daniel Keep, C. J. Flaherty Dec 2012

Simulations In 3d Tactics, Interdiction And Multi-Agent Modelling, A. R. Green, I. C. Piper, Daniel Keep, C. J. Flaherty

Dr Ian Piper

The analysis of vulnerabilities in large complex spaces is fundamentally problematic. The lack of capacity to generate a threat assessment merely exacerbates this problem. Lacking as well, in current literature is a developed methodology. To overcome this problem, we propose an approach using multi-agent modelling, which is also melded with three dimensional (3D) tactical understandings. Our approach builds on a microsimulation decision support tool, which was developed for a behavioural simulation of CBRN events. Microsimulation is based on the individual; who as an individual has a number of attributes, and which are stochastic (when repeated within an attribute). This approach …


Simple, Robust And Accurate Head-Pose Tracking Using A Single Camera, S. Meers, Koren Ward, I. Piper Dec 2012

Simple, Robust And Accurate Head-Pose Tracking Using A Single Camera, S. Meers, Koren Ward, I. Piper

Dr Ian Piper

This paper describes an inexpensive, robust method for tracking the head position and orientation of the user by using a single low-cost USB camera and infrared light emitting diodes concealed within spectacle frames worn by the user. Unlike gaze and head-pose tracking systems which rely on high-resolution stereo cameras and complex image processing hardware and software to find and track facial features on the user, the proposed system is able to efficiently locate and track the head's orientation and distance relative to the camera with little processing. Due to the infrared light emitting diodes having fixed geometry, the system does …


A Conceptlink Graph For Text Structure Mining, Rowena Chau, Ah Chung Tsoi, Markus Hagenbuchner, Vincent Lee Dec 2012

A Conceptlink Graph For Text Structure Mining, Rowena Chau, Ah Chung Tsoi, Markus Hagenbuchner, Vincent Lee

Dr Markus Hagenbuchner

Most text mining methods are based on representing documents using a vector space model, commonly known as a bag of word model, where each document is modeled as a linear vector representing the occurrence of independent words in the text corpus. It is well known that using this vector-based representation, important information, such as semantic relationship among concepts, is lost. This paper proposes a novel text representation model called ConceptLink graph. The ConceptLink graph does not only represent the content of the document, but also captures some of its underlying semantic structure in terms of the relationships among concepts. The …


Computational Capabilities Of Graph Neural Networks, Franco Scarselli, Marco Gori, Ah Chung Tsoi, Markus Hagenbuchner, Gabriele Monfardini Dec 2012

Computational Capabilities Of Graph Neural Networks, Franco Scarselli, Marco Gori, Ah Chung Tsoi, Markus Hagenbuchner, Gabriele Monfardini

Dr Markus Hagenbuchner

In this paper, we will consider the universal approximation properties of a recently introduced neural network model called graph neural network (GNN) which can be used to process structured data inputs, e.g. acyclic graph, cyclic graph, directed or un-directed graphs. This class of neural networks implements a function (G, n) 2 IRm that maps a graph Gand one of its nodes n onto an m-dimensional Euclidean space. We characterize the functions that can be approximated by GNNs, in probability, up to any prescribed degree of precision. This set contains the maps that satisfy a property, called preservation of the unfolding …


Ranking Attack Graphs With Graph Neural Networks, Liang Lu, Rei Safavi-Naini, Markus Hagenbuchner, Willy Susilo, Jeffrey Horton, Sweah Liang Yong, Ah Chung Tsoi Dec 2012

Ranking Attack Graphs With Graph Neural Networks, Liang Lu, Rei Safavi-Naini, Markus Hagenbuchner, Willy Susilo, Jeffrey Horton, Sweah Liang Yong, Ah Chung Tsoi

Dr Markus Hagenbuchner

Network security analysis based on attack graphs has been applied extensively in recent years. The ranking of nodes in an attack graph is an important step towards analyzing network security. This paper proposes an alternative attack graph ranking scheme based on a recent approach to machine learning in a structured graph domain, namely, Graph Neural Networks (GNNs). Evidence is presented in this paper that the GNN is suitable for the task of ranking attack graphs by learning a ranking function from examples and generalizes the function to unseen possibly noisy data, thus showing that the GNN provides an effective alternative …


Data Curation Is For Everyone! The Case For Master's And Baccalaureate Institutional Engagement With Data Curation, Yasmeen Shorish Dec 2012

Data Curation Is For Everyone! The Case For Master's And Baccalaureate Institutional Engagement With Data Curation, Yasmeen Shorish

Yasmeen Shorish

This article describes the fundamental challenges to data curation, how these challenges may be compounded for smaller institutions, and how data management is an essential and manageable component of data curation. Data curation is often discussed within the confines of large, research universities. As a result, master’s and baccalaureate institutions may be left with the impression that they cannot engage with data curation. However, by proactively engaging with faculty, libraries of all sizes can build closer relationships and help educate faculty on data documentation and organization best practices. Experiences from one master’s comprehensive institution as it engages with data management …


A Model For Coherent Distributed Systems, Robert L. Brown, Peter J. Denning, Walter F. Tichy Dec 2012

A Model For Coherent Distributed Systems, Robert L. Brown, Peter J. Denning, Walter F. Tichy

Dr Robert Brown

No abstract provided.


Automatic, Remote Status Lights For Vax Unix, Douglas E. Comer, Robert L. Brown Dec 2012

Automatic, Remote Status Lights For Vax Unix, Douglas E. Comer, Robert L. Brown

Dr Robert Brown

No abstract provided.


Should Distributed Systems Be Hidden?, Peter J. Denning, Robert L. Brown Dec 2012

Should Distributed Systems Be Hidden?, Peter J. Denning, Robert L. Brown

Dr Robert Brown

No abstract provided.


P2cp: A New Cloud Storage Model To Enhance Performance Of Cloud Services, Zhe Sun, Jun Shen, Ghassan Beydoun Dec 2012

P2cp: A New Cloud Storage Model To Enhance Performance Of Cloud Services, Zhe Sun, Jun Shen, Ghassan Beydoun

Associate Professor Ghassan Beydoun

This paper presents a storage model named Peer to Cloud and Peer (P2CP). Assuming that the P2CP model follows the Poisson process or Little’s law, we prove that the speed and availability of P2CP is generally better than that of the pure Peer to Peer (P2P) model, the Peer to Server, Peer (P2SP) model or the cloud model. A key feature of our P2CP is that it has three data transmission tunnels: the cloud-user data transmission tunnel, the clients’ data transmission tunnel, and the common data transmission tunnel. P2CP uses the cloud storage system as a common storage system. When …


Security Analysis Of Two Signcryption Schemes, Guilin Wang, Robert H. Deng, Dongjin Kwak, Sangjae Moon Dec 2012

Security Analysis Of Two Signcryption Schemes, Guilin Wang, Robert H. Deng, Dongjin Kwak, Sangjae Moon

Dr Guilin Wang

Signcryption is a new cryptographic primitive that performs signing and encryption simultaneously, at a cost significantly lower than that required by the traditional signature-then-encryption approach. In this paper, we present a security analysis of two such schemes: the Huang-Chang convertible signcryption scheme, and the Kwak-Moon group signcryption scheme. Our results show that both schemes are insecure. Specifically, the Huang-Chang scheme fails to provide confidentiality, while the Kwak-Moon scheme does not satisfy the properties of unforgeability, coalition-resistance, and traceability.


Comments On "A Practical (T, N) Threshold Proxy Signature Scheme Based On The Rsa Cryptosystem", Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng Dec 2012

Comments On "A Practical (T, N) Threshold Proxy Signature Scheme Based On The Rsa Cryptosystem", Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng

Dr Guilin Wang

In a (t, n) threshold proxy signature scheme based on RSA, any t or more proxy signers can cooperatively generate a proxy signature while t-1 or fewer of them can't do it. The threshold proxy signature scheme uses the RSA cryptosystem to generate the private and the public key of the signers. In this article, we discuss the implementation and comparison of some threshold proxy signature schemes that are based on the RSA cryptosystem. Comparison is done on the basis of time complexity, space complexity and communication overhead. We compare the performance of four schemes: Hwang et al., Wen et …


Proxy Signature Scheme With Multiple Original Signers For Wireless E-Commerce Applications, Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng Dec 2012

Proxy Signature Scheme With Multiple Original Signers For Wireless E-Commerce Applications, Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng

Dr Guilin Wang

In a proxy signature scheme, a user delegates his/her signing capability to another user in such a way that the latter can sign messages on behalf of the former. We propose an efficient and secure proxy signature scheme with multiple original signers. Our scheme is suitable for wireless electronic commerce applications, since the overheads of computation and communication are low. As an example, we present an electronic air ticket booking scheme for wireless customers.


Diseñando Colisiones De Satélites En La Guerra Cibernética Encubierta, Jan Kallberg Dec 2012

Diseñando Colisiones De Satélites En La Guerra Cibernética Encubierta, Jan Kallberg

Jan Kallberg

La guerra concentrada en la red depende de la red de información global para capacidades de combate conjuntas.3 La capa fundamental crea la capacidad de combate global como la columna vertebral espacial de la red de información donde los haberes espaciales son el elemento decisivo. EE.UU. depende de las capacidades espaciales para su éxito y la seguridad nacional de EE.UU. se basa hoy en día en un número limitado de satélites muy utilizados. Estos satélites son cruciales para la disuasión estratégica, la vigilancia, la recopilación de inteligencia y las comunicaciones militares. Si la disuasión estratégica falla, los satélites forman parte …


P2cp: A New Cloud Storage Model To Enhance Performance Of Cloud Services, Zhe Sun, Jun Shen, Ghassan Beydoun Dec 2012

P2cp: A New Cloud Storage Model To Enhance Performance Of Cloud Services, Zhe Sun, Jun Shen, Ghassan Beydoun

Dr Jun Shen

This paper presents a storage model named Peer to Cloud and Peer (P2CP). Assuming that the P2CP model follows the Poisson process or Little’s law, we prove that the speed and availability of P2CP is generally better than that of the pure Peer to Peer (P2P) model, the Peer to Server, Peer (P2SP) model or the cloud model. A key feature of our P2CP is that it has three data transmission tunnels: the cloud-user data transmission tunnel, the clients’ data transmission tunnel, and the common data transmission tunnel. P2CP uses the cloud storage system as a common storage system. When …


The Return Of Dr. Strangelove: How Austerity Makes Us Stop Worrying And Love The Bomb…And Cyber War, Jan Kallberg, Adam Lowther Nov 2012

The Return Of Dr. Strangelove: How Austerity Makes Us Stop Worrying And Love The Bomb…And Cyber War, Jan Kallberg, Adam Lowther

Jan Kallberg

With sequestration looming—generating significant cuts to defense spending—the United States may find itself increasingly relying on nuclear and cyber deterrence as an affordable way to guarantee national sovereignty and prevent major conflict. While earlier defense planning and acquisitions were based on economic conditions that no longer exist, Congress’ options to balance the budget by cutting defense spending are politically palatable because far fewer American are “defense voters” than “social welfare voters,” according to a number of recent public opinion surveys.


Scaling Bayesian Network Parameter Learning With Expectation Maximization Using Mapreduce, Erik B. Reed, Ole J. Mengshoel Nov 2012

Scaling Bayesian Network Parameter Learning With Expectation Maximization Using Mapreduce, Erik B. Reed, Ole J. Mengshoel

Ole J Mengshoel

Bayesian network (BN) parameter learning from incomplete data can be a computationally expensive task for incomplete data. Applying the EM algorithm to learn BN parameters is unfortunately susceptible to local optima and prone to premature convergence. We develop and experiment with two methods for improving EM parameter learning by using MapReduce: Age-Layered Expectation Maximization (ALEM) and Multiple Expectation Maximization (MEM). Leveraging MapReduce for distributed machine learning, these algorithms (i) operate on a (potentially large) population of BNs and (ii) partition the data set as is traditionally done with MapReduce machine learning. For example, we achieved gains using the Hadoop implementation …


Mapreduce For Bayesian Network Parameter Learning Using The Em Algorithm, Aniruddha Basak, Irina Brinster, Ole J. Mengshoel Nov 2012

Mapreduce For Bayesian Network Parameter Learning Using The Em Algorithm, Aniruddha Basak, Irina Brinster, Ole J. Mengshoel

Ole J Mengshoel

This work applies the distributed computing framework MapReduce to Bayesian network parameter learning from incomplete data. We formulate the classical Expectation Maximization (EM) algorithm within the MapReduce framework. Analytically and experimentally we analyze the speed-up that can be obtained by means of MapReduce. We present details of the MapReduce formulation of EM, report speed-ups versus the sequential case, and carefully compare various Hadoop cluster configurations in experiments with Bayesian networks of different sizes and structures.


On The Interaction Of Data Representation And Routing In Sensor Networks, Deepak Ganesan Nov 2012

On The Interaction Of Data Representation And Routing In Sensor Networks, Deepak Ganesan

Deepak Ganesan

We consider data gathering by a network with a sink node and a tree communication structure, where the goal is to minimize the total transmission cost of transporting the information collected by the nodes, to the sink node. This problem requires a joint optimization of the data representation at the nodes and of the transmission structure. First, we study the case when the measured data are correlated random variables, both in the lossless scenario with Slepian-Wolf coding, and in the high-resolution lossy scenario with optimal rate-distortion allocation. We show that the optimal transmission structure is the shortest path tree, and …


The Economics Of Open Source, Christopher H. Hoebeke Nov 2012

The Economics Of Open Source, Christopher H. Hoebeke

Christopher H Hoebeke

No abstract provided.


Developing High Frequency Foreign Exchange Trading Systems, Bruce Vanstone, Tobias Hahn, Gavin Finnie Nov 2012

Developing High Frequency Foreign Exchange Trading Systems, Bruce Vanstone, Tobias Hahn, Gavin Finnie

Bruce Vanstone

The foreign exchange (FX) spot markets are well suited to high frequency trading. They are highly liquid, allow leverage, and trade 24 hours a day, 5 days a week. This paper documents and tests the stylized facts known about high-frequency FX markets. It then postulates a high frequency trading system on the basis of these stylized facts. Benchmarking confirms the robustness of the approach, demonstrating the role algorithmic trading has to play in higher frequency trading environments.


Developing High Frequency Foreign Exchange Trading Systems, Bruce Vanstone, Tobias Hahn, Gavin Finnie Nov 2012

Developing High Frequency Foreign Exchange Trading Systems, Bruce Vanstone, Tobias Hahn, Gavin Finnie

Tobias Hahn

The foreign exchange (FX) spot markets are well suited to high frequency trading. They are highly liquid, allow leverage, and trade 24 hours a day, 5 days a week. This paper documents and tests the stylized facts known about high-frequency FX markets. It then postulates a high frequency trading system on the basis of these stylized facts. Benchmarking confirms the robustness of the approach, demonstrating the role algorithmic trading has to play in higher frequency trading environments.


Library Impact Statement For Csc 423 Network Intrusion Detection And Defense, Amanda Izenstark Nov 2012

Library Impact Statement For Csc 423 Network Intrusion Detection And Defense, Amanda Izenstark

Amanda Izenstark

Library Impact Statement in response to new course proposal for CSC 423 Network Intrusion Detection and Defense. New course was supported with no need for additional resources.


Library Impact Statement For Csc 523 Advanced Intrusion Detection And Defense, Amanda Izenstark Nov 2012

Library Impact Statement For Csc 523 Advanced Intrusion Detection And Defense, Amanda Izenstark

Amanda Izenstark

Library Impact Statement for CSC 523 Advanced Intrusion Detection and Defense. No new library resources are required to support this course.