Open Access. Powered by Scholars. Published by Universities.®

Databases and Information Systems Commons™

Open Access. Powered by Scholars. Published by Universities.®

7,602 Full-Text Articles 11,203 Authors 4,994,161 Downloads 215 Institutions

All Articles in Databases and Information Systems

Faceted Search

7,602 full-text articles. Page 259 of 283.

A Study Of Correlations Between The Definition And Application Of The Gene Ontology, Yuji Mo 2011 University of Nebraska-Lincoln

A Study Of Correlations Between The Definition And Application Of The Gene Ontology, Yuji Mo

Department of Computer Electronics and Engineering: Dissertations, Theses, and Student Research

When using the Gene Ontology (GO), nucleotide and amino acid sequences are annotated by terms in a structured and controlled vocabulary organized into relational graphs. The usage of the vocabulary (GO terms) in the annotation of these sequences may diverge from the relations defined in the ontology. We measure the consistency of the use of GO terms by comparing GO's defined structure to the terms' application. To do this, we first use synthetic data with different characteristics to understand how these characteristics influence the correlation values determined by various similarity measures. Using these results as a baseline, we found that …


Overview Of Contrast Data Mining As A Field And Preview Of An Upcoming Book, Guozhu Dong, James Bailey 2011 Wright State University - Main Campus

Overview Of Contrast Data Mining As A Field And Preview Of An Upcoming Book, Guozhu Dong, James Bailey

Kno.e.sis Publications

This report provides an overview of the field of contrast data mining and its applications, and offers a preview of an upcoming book on the topic. The importance of contrasting is discussed and a brief survey is given covering the following topics: general definitions and terminology for contrast patterns, representative contrast pattern mining algorithms, applications of contrast mining for fundamental data mining tasks such as classification and clustering, applications of contrast mining in bioinformatics, medicine, blog analysis, image analysis and subgroup mining, results on contrast based dataset similarity measure, and on analyzing item interaction in contrast patterns, and open research …


Computing Inconsistency Measure Based On Paraconsistent Semantics, Pascal Hitzler, Yue Ma, Guilin Qi 2011 Wright State University - Main Campus

Computing Inconsistency Measure Based On Paraconsistent Semantics, Pascal Hitzler, Yue Ma, Guilin Qi

Computer Science and Engineering Faculty Publications

Measuring inconsistency in knowledge bases has been recognized as an important problem in several research areas. Many methods have been proposed to solve this problem and a main class of them is based on some kind of paraconsistent semantics. However, existing methods suffer from two limitations: (i) they are mostly restricted to propositional knowledge bases; (ii) very few of them discuss computational aspects of computing inconsistency measures. In this article, we try to solve these two limitations by exploring algorithms for computing an inconsistency measure of first-order knowledge bases. After introducing a four-valued semantics for first-order logic, we define an …


Quantifying Computer Network Security, Ian Burchett 2011 Western Kentucky University

Quantifying Computer Network Security, Ian Burchett

Masters Theses & Specialist Projects

Simplifying network security data to the point that it is readily accessible and usable by a wider audience is increasingly becoming important, as networks become larger and security conditions and threats become more dynamic and complex, requiring a broader and more varied security staff makeup. With the need for a simple metric to quantify the security level on a network, this thesis proposes: simplify a network’s security risk level into a simple metric. Methods for this simplification of an entire network’s security level are conducted on several characteristic networks. Identification of computer network port vulnerabilities from NIST’s Network Vulnerability Database …


Four-Jet Final State Production In E+E- Collisions At Centre-Of-Mass Energies Of 130 And 136 Gev, D. BUSKULIC, M. THULASIDAS 2011 Singapore Management University

Four-Jet Final State Production In E+E- Collisions At Centre-Of-Mass Energies Of 130 And 136 Gev, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

The four-jet final state is analyzed to search for hadronic decays of pair-produced heavy particles. The analysis uses the ALEPH data collected at LEP in November 1995 at centre-of-mass energies of 130 and 136 GeV, corresponding to a total integrated luminosity of 5.7 pb1 . An excess of four-jet events is observed with respect to the standard model predictions. In addition, these events exhibit an enhancement in the sum of the two di-jet masses around 105 GeV/c 2 . The properties of these events are studied and compared to the expectations from standard processes and to pair production hypotheses


Processj: A Process-Oriented Programming Language, Matthew Sowders 2011 University of Nevada, Las Vegas

Processj: A Process-Oriented Programming Language, Matthew Sowders

UNLV Theses, Dissertations, Professional Papers, and Capstones

Java is a general purpose object-oriented programming language that has been widely adopted. Because of its high adoption rate and its lineage as a C-style language, its syntax is familiar to many programmers. The downside is that Java is not natively concurrent. Volumes have been written about concurrent programming in Java; however, concurrent programming is difficult to reason about within an object-oriented paradigm and so is difficult to get right.

occam -π is a general purpose process-oriented programming language. Concurrency is part of the theoretical underpinnings of the language. Concurrency is simple to reason about within an occam -π application …


Study Of Feature Selection Algorithms For Text-Categorization, Kandarp Dave 2011 University of Nevada, Las Vegas

Study Of Feature Selection Algorithms For Text-Categorization, Kandarp Dave

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis will discuss feature selection algorithms for text-categorization. Feature selection algorithms are very important, as they can make-or-break a categorization engine. The feature selection algorithms that will be discussed in this thesis are Document Frequency, Information Gain, Chi Squared, Mutual Information, NGL (Ng-Goh-Low) coefficient, and GSS (Galavotti-Sebastiani-Simi) coefficient . The general idea of any feature selection algorithm is to determine importance of words using some measure that can keep informative words, and remove non-informative words, which can then help the text-categorization engine categorize a document, D , into some category, C . These feature selection methods are explained, implemented, …


An Effective Approach For Topicspecific Opinion Summarization, Binyang LI, Lanjun ZHOU, Wei GAO, Kam-Fai WONG, Zhongyu WEI 2011 Singapore Management University

An Effective Approach For Topicspecific Opinion Summarization, Binyang Li, Lanjun Zhou, Wei Gao, Kam-Fai Wong, Zhongyu Wei

Research Collection School Of Computing and Information Systems

Topic-specific opinion summarization (TOS) plays an important role in helping users digest online opinions, which targets to extract a summary of opinion expressions specified by a query, i.e. topic-specific opinionated information (TOI). A fundamental problem in TOS is how to effectively represent the TOI of an opinion so that salient opinions can be summarized to meet user’s preference. Existing approaches for TOS are either limited by the mismatch between topic-specific information and its corresponding opinionated information or lack of ability to measure opinionated information associated with different topics, which in turn affect the performance seriously. In this paper, we represent …


Modeling Social Strength In Social Media Community Via Kernel-Based Learning, Jinfeng ZHUANG, Tao MEI, Steven C. H. HOI, Xian-Sheng HUA, Shipeng LI 2011 Nanyang Technological University

Modeling Social Strength In Social Media Community Via Kernel-Based Learning, Jinfeng Zhuang, Tao Mei, Steven C. H. Hoi, Xian-Sheng Hua, Shipeng Li

Research Collection School Of Computing and Information Systems

Modeling continuous social strength rather than conventional binary social ties in the social network can lead to a more precise and informative description of social relationship among people. In this paper, we study the problem of social strength modeling (SSM) for the users in a social media community, who are typically associated with diverse form of data. In particular, we take Flickr---the most popular online photo sharing community---as an example, in which users are sharing their experiences through substantial amounts of multimodal contents (e.g., photos, tags, geo-locations, friend lists) and social behaviors (e.g., commenting and joining interest groups). Such heterogeneous …


Validation Of A Model Of Information Systems User Competency, Brenda ESCHENBRENNER, Fiona Fui-hoon NAH 2011 Singapore Management University

Validation Of A Model Of Information Systems User Competency, Brenda Eschenbrenner, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

IS user competency, or the ability to realize the fullest potential and the greatest performance from IS use, is important for IS users. However, which factors contribute to IS user competency is unclear. Based on the findings of previous research, a model of IS user competency was developed that focuses on IS-specific characteristics: (i) domain knowledge of and skills in IS, (ii) willingness to try and to explore IS, and (iii) capability of perceiving IS value. The model was validated using the survey approach and the findings suggest that all three factors are pivotal to IS user competency, with willingness …


Contributions Of Financial Sector Reforms And Credit Supply To Nigerian Agricultural Sector (1978-2009), Anthony O. Onoja, M. E. Onu, S. Ajodo-Ohiemi 2011 Department of Agricultural Economics and Extension University of Port Harcourt, Nigeria

Contributions Of Financial Sector Reforms And Credit Supply To Nigerian Agricultural Sector (1978-2009), Anthony O. Onoja, M. E. Onu, S. Ajodo-Ohiemi

CBN Journal of Applied Statistics (JAS)

This study analyzed the trends and pattern of institutional credit supply to agriculture during pre- and post-financial reforms along with their determinants. It then compared the effects of reform policies on access to institutional credits in Nigerian agricultural sector before and after the reforms (1978 - 1985; and 1986 -2009). Relying mainly on time series data from CBN and NBS, it used ordinary least squares method (linear, semi-log and double log) to model the determinants of banking sector lending to the agricultural sector during the review period. The models were subjected to several econometric tests before accepting one. Chow test …


Determinants Of Foreign Reserves In Nigeria: An Autoregressive Distributed Lag Approach, David Irefin, Baba N. Yaaba 2011 Department of Economics, University of Maiduguri

Determinants Of Foreign Reserves In Nigeria: An Autoregressive Distributed Lag Approach, David Irefin, Baba N. Yaaba

CBN Journal of Applied Statistics (JAS)

On global scale, central banks’ holdings of foreign reserves have escalated sharply in recent years. World international reserves holdings have risen significantly from US$1.2 trillion in 1995 to nearly US$10.0 trillion in June 2011. Dominant among these reserves are concentrated in the hands of few countries. Ten major holders of foreign reserves are mostly from Asia. Oil exporting countries in Africa and the Middle East are not left out in this trend. Nigeria’s foreign reserves rose from US$5.5 billion in 1999 to US$62.40 billion in July 2008, making Nigeria the twenty-fourth largest reserves holder in the world. This pace of …


Effects Of Exchange Rate Movements On Economic Growth In Nigeria, Eme O. Akpan, Johnson A. Atan 2011 Department of Economics, University of Ibadan

Effects Of Exchange Rate Movements On Economic Growth In Nigeria, Eme O. Akpan, Johnson A. Atan

CBN Journal of Applied Statistics (JAS)

This study investigates the effect of exchange rate movements on real output growth in Nigeria. Based on quarterly series for the period 1986 to 2010, the paper examines the possible direct and indirect relationship between exchange rates and GDP growth. The relationship is derived in two ways using a simultaneous equations model within a fully specified (but small) macroeconomic model. A Generalised Method of Moments (GMM) technique was explored. The estimation results suggest that there is no evidence of a strong direct relationship between changes in exchange rate and output growth. Rather, Nigeria’s economic growth has been directly affected by …


Exchange Rate Volatility In Nigeria: Consistency, Persistency & Severity Analyses, Babatunde Adeoye, Akinwande A. Atanda 2011 Datatric Research Consulting, Nigeria

Exchange Rate Volatility In Nigeria: Consistency, Persistency & Severity Analyses, Babatunde Adeoye, Akinwande A. Atanda

CBN Journal of Applied Statistics (JAS)

The adoption of the International Monetary Fund (IMF) Structural Adjustment Programme (SAP) in 1986 resulted in the transition from fixed exchange rate regime to floating exchange rate regime in Nigeria. Ever since, the exchange rate of naira vis-à-vis the U.S dollar has attained varying rates all through different time horizons. On this basis, this study examines the consistency, persistency, and severity (degree) of volatility in exchange rate of Nigerian currency (naira) vis-a-vis the United State dollar using monthly time series data from 1986 to 2008. The standard Purchasing Power Parity (PPP) model was used to analyze the long-run consistency of …


Foreign Private Investment And Economic Growth In Nigeria: A Cointegrated Var And Granger Causality Analysis, F. Z. Abdullahi, S. Ladan, Haruna R. Bakari 2011 1Department of Statistics Collage of Science and Technology. Waziri Umaru Federal Polytechnic Birnin Kebbi, Nigeria

Foreign Private Investment And Economic Growth In Nigeria: A Cointegrated Var And Granger Causality Analysis, F. Z. Abdullahi, S. Ladan, Haruna R. Bakari

CBN Journal of Applied Statistics (JAS)

This research uses a cointegration VAR model to study the contemporaneous long-run dynamics of the impact of Foreign Private Investment (FPI), Interest Rate (INR) and Inflation rate (IFR) on Growth Domestic Products (GDP) in Nigeria for the period January 1970 to December 2009. The Unit Root Test suggests that all the variables are integrated of order 1. The VAR model was appropriately identified using AIC information criteria and the VECM model has exactly one cointegration relation. The study further investigates the causal relationship using the Granger causality analysis of VECM which indicates a uni-directional causality relationship between GDP and FDI …


Banking Sector Credit And Economic Growth In Nigeria: An Empirical Investigation, Aniekan O. Akpansung, Sikiru J. Babalola 2011 Department of Economics, Modibbo Adama University of Technology, Yola, Nigeria

Banking Sector Credit And Economic Growth In Nigeria: An Empirical Investigation, Aniekan O. Akpansung, Sikiru J. Babalola

CBN Journal of Applied Statistics (JAS)

The paper examines the relationship between banking sector credit and economic growth in Nigeria over the period 1970-2008. The causal links between the pairs of variables of interest were established using Granger causality test while a Two-Stage Least Squares (TSLS) estimation technique was used for the regression models. The results of Granger causality test show evidence of unidirectional causal relationship from GDP to private sector credit (PSC) and from industrial production index (IND) to GDP. Estimated regression models indicate that private sector credit impacts positively on economic growth over the period of coverage in this study. However, lending (interest) rate …


Consolidated Study On Query Expansion, Abhishek Biruduraju 2011 University of Nevada, Las Vegas

Consolidated Study On Query Expansion, Abhishek Biruduraju

UNLV Theses, Dissertations, Professional Papers, and Capstones

A typical day of million web users all over the world starts with a simple query. The quest for information on a particular topic drives them to search for it, and in the pursuit of their info the terms they supply for queries varies from person to person depending on the knowledge they have. With a vast collection of documents available on the web universe it is the onus of the retrieval system to return only those documents that are relevant and satisfy the user’s search requirements. The document mismatch problem is resolved by appending extra query terms to the …


Parallel Machines Scheduling With Applications To Internet Ad-Slot Placement, Shaista Lubna 2011 University of Nevada, Las Vegas

Parallel Machines Scheduling With Applications To Internet Ad-Slot Placement, Shaista Lubna

UNLV Theses, Dissertations, Professional Papers, and Capstones

We consider a class of problems of scheduling independent jobs on identical, uniform and unrelated parallel machines with an objective of achieving an optimal schedule. The primary focus is on the minimization of the maximum completion time of the jobs, commonly referred to as Makespan (C max ). We survey and present examples of uniform machines and its applications to the single slot and multiple slots based on bids and budgets.

The Internet is an important advertising medium attracting large number of advertisers and users. When a user searches for a query, a search engine returns a set of results …


The Valuation Of User-Generated Content: A Structural, Stylistic And Semantic Analysis Of Online Reviews, Noi Sian KOH 2011 Singapore Management University

The Valuation Of User-Generated Content: A Structural, Stylistic And Semantic Analysis Of Online Reviews, Noi Sian Koh

Dissertations and Theses Collection (Open Access)

The ability and ease for users to create and publish content has provided vast amount of online product reviews. However, the amount of data is overwhelmingly large and unstructured, making information difficult to quantify. This creates challenge in understanding how online reviews affect consumers’ purchase decisions. In my dissertation, I explore the structural, stylistic and semantic content of online reviews. Firstly, I present a measurement that quantifies sentiments with respect to a multi-point scale and conduct a systematic study on the impact of online reviews on product sales. Using the sentiment metrics generated, I estimate the weight that customers place …


Vireo@Trecvid 2011: Instance Search, Semantic Indexing, Multimedia Event Detection And Known-Item Search, Chong-wah NGO, Shi-Ai ZHU, Wei ZHANG, Chun-Chet TAN, Ting YAO, Lei PANG, Hung-Khoon TAN 2011 Singapore Management University

Vireo@Trecvid 2011: Instance Search, Semantic Indexing, Multimedia Event Detection And Known-Item Search, Chong-Wah Ngo, Shi-Ai Zhu, Wei Zhang, Chun-Chet Tan, Ting Yao, Lei Pang, Hung-Khoon Tan

Research Collection School Of Computing and Information Systems

The vireo group participated in four tasks: instance search, semantic indexing, multimedia event detection and known-item search. In this paper,we will present our approaches and discuss the evaluation results.


Digital Commons powered by bepress