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

Databases and Information Systems Commons™

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

7,250 Full-Text Articles 10,408 Authors 4,901,411 Downloads 214 Institutions

All Articles in Databases and Information Systems

Faceted Search

7,250 full-text articles. Page 227 of 268.

An Analysis Of Generational Caching Implemented In A Production Website, Marc E. Zych 2013 California Polytechnic State University, San Luis Obispo

An Analysis Of Generational Caching Implemented In A Production Website, Marc E. Zych

Master's Theses

Website scaling has been an issue since the inception of the web. The demand for user generated content and personalized web pages requires the use of a database for a storage engine. Unfortunately, scaling the database to handle large amounts of traffic is still a problem many companies face. One such company is iFixit, a provider of free, publicly-editable, online repair manuals. Like many websites, iFixit uses Memcached to decrease database load and improve response time. However, the caching strategy used is a very ad hoc one and therefore can be greatly improved.

Most research regarding web application caching focuses …


Concept Graphs: Applications To Biomedical Text Categorization And Concept Extraction, Said Bleik 2013 New Jersey Institute of Technology

Concept Graphs: Applications To Biomedical Text Categorization And Concept Extraction, Said Bleik

Dissertations

As science advances, the underlying literature grows rapidly providing valuable knowledge mines for researchers and practitioners. The text content that makes up these knowledge collections is often unstructured and, thus, extracting relevant or novel information could be nontrivial and costly. In addition, human knowledge and expertise are being transformed into structured digital information in the form of vocabulary databases and ontologies. These knowledge bases hold substantial hierarchical and semantic relationships of common domain concepts. Consequently, automating learning tasks could be reinforced with those knowledge bases through constructing human-like representations of knowledge. This allows developing algorithms that simulate the human reasoning …


Main-Stream Media Behaviour Analysis On Twitter: A Case Study On Uk General Election, Zhongyu WEI, Yulan HE, Wei GAO, Binyang LI, Lanjun ZHOU, Kam-Fai WONG 2013 Singapore Management University

Main-Stream Media Behaviour Analysis On Twitter: A Case Study On Uk General Election, Zhongyu Wei, Yulan He, Wei Gao, Binyang Li, Lanjun Zhou, Kam-Fai Wong

Research Collection School Of Computing and Information Systems

With the development of social media tools such as Facebook and Twitter, mainstream media organizations including newspapers and TV media have played an active role in engaging with their audience and strengthening their influence on the recently emerged platforms. In this paper, we analyze the behavior of mainstream media on Twitter and study how they exert their influence to shape public opinion during the UK's 2010 General Election. We first propose an empirical measure to quantify mainstream media bias based on sentiment analysis and show that it correlates better with the actual political bias in the UK media than the …


Hybrid Methods For Feature Selection, Iunniang Cheng 2013 Western Kentucky University

Hybrid Methods For Feature Selection, Iunniang Cheng

Masters Theses & Specialist Projects

Feature selection is one of the important data preprocessing steps in data mining. The feature selection problem involves finding a feature subset such that a classification model built only with this subset would have better predictive accuracy than model built with a complete set of features. In this study, we propose two hybrid methods for feature selection. The best features are selected through either the hybrid methods or existing feature selection methods. Next, the reduced dataset is used to build classification models using five classifiers. The classification accuracy was evaluated in terms of the area under the Receiver Operating Characteristic …


Ikriya: Simulating Software Quality Enhancement With Selected Replacement Policies, Sindhu Dharani Murthy 2013 Western Kentucky University

Ikriya: Simulating Software Quality Enhancement With Selected Replacement Policies, Sindhu Dharani Murthy

Masters Theses & Specialist Projects

The quality of information systems in any organization helps to determine the
efficiency of the organization. Many organizations maintain a custom software portfolio, whose quality is important to the organization. Management would like to optimize the portfolio’s quality. Decisions about software replacement or enhancement are made based on organizational needs and priorities. The development resources allocated help in determining the quality of new software, and should be put to optimal use. Enhancing existing software might sound cheap and easy but it is not always efficient. This thesis proposes a simulation model - iKriya - for this problem. It explores the …


A Hybrid Recommendation System Based On Association Rules, Ahmed Alsalama 2013 Western Kentucky University

A Hybrid Recommendation System Based On Association Rules, Ahmed Alsalama

Masters Theses & Specialist Projects

Recommendation systems are widely used in e-commerce applications. The
engine of a current recommendation system recommends items to a particular user based on user preferences and previous high ratings. Various recommendation schemes such as collaborative filtering and content-based approaches are used to build a recommendation system. Most of current recommendation systems were developed to fit a certain domain such as books, articles, and movies. We propose a hybrid framework recommendation system to be applied on two dimensional spaces (User × Item) with a large number of users and a small number of items. Moreover, our proposed framework makes use of …


Data Near Here: Bringing Relevant Data Closer To Scientists, Veronika M. Megler, David Maier 2013 Portland State University

Data Near Here: Bringing Relevant Data Closer To Scientists, Veronika M. Megler, David Maier

Computer Science Faculty Publications and Presentations

Large scientific repositories run the risk of losing value as their holdings expand, if it means increased effort for a scientist to locate particular datasets of interest. We discuss the challenges that scientists face in locating relevant data, and present our work in applying Information Retrieval techniques to dataset search, as embodied in the Data Near Here application.


Developing A Mobile-Commerce Financial Transaction Processing Model, Edward Nathaniel Thomas Charles Williams Jr. 2013 Columbus State University

Developing A Mobile-Commerce Financial Transaction Processing Model, Edward Nathaniel Thomas Charles Williams Jr.

Theses and Dissertations

The topic for this Master’s Thesis is selected in compliance with the guidelines to complete a Master of Science in Applied Computer Science at Columbus State University. The problem to be addressed by this thesis is to produce an open standard for an m-commerce financial transaction processing system based on current e-commerce standards and mobile technology. This solution was to be specifically designed to build upon the strengths of a mobile platform using current smartphone and tablet technology.

An open source software stack in combination with a cloud computing solution was used to create a working example of the specification. …


A Comparison Of Leading Database Storage Engines In Support Of Online Analytical Processing In An Open Source Environment, Gabriel Tocci 2013 East Tennessee State University

A Comparison Of Leading Database Storage Engines In Support Of Online Analytical Processing In An Open Source Environment, Gabriel Tocci

Electronic Theses and Dissertations

Online Analytical Processing (OLAP) has become the de facto data analysis technology used in modern decision support systems. It has experienced tremendous growth, and is among the top priorities for enterprises. Open source systems have become an effective alternative to proprietary systems in terms of cost and function. The purpose of the study was to investigate the performance of two leading database storage engines in an open source OLAP environment. Despite recent upgrades in performance features for the InnoDB database engine, the MyISAM database engine is shown to outperform the InnoDB database engine under a standard benchmark. This result was …


Unified Entity Search In Social Media Community, Ting YAO, Yuan LIU, Chong-wah NGO, Tao MEI 2013 Singapore Management University

Unified Entity Search In Social Media Community, Ting Yao, Yuan Liu, Chong-Wah Ngo, Tao Mei

Research Collection School Of Computing and Information Systems

The search for entities is the most common search behavior on the Web, especially in social media communities where entities (such as images, videos, people, locations, and tags) are highly heterogeneous and correlated. While previous research usually deals with these social media entities separately, we are investigating in this paper a unified, multilevel, and correlative entity graph to represent the unstructured social media data, through which various applications (e.g., friend suggestion, personalized image search, image tagging, etc.) can be realized more effectively in one single framework. We regard the social media objects equally as “entities” and all of these applications …


Fragmented Social Media: A Look Into Selective Exposure To Political News, Jisun AN, Daniele QUERCIA, Jon CROWCROFT 2013 Singapore Management University

Fragmented Social Media: A Look Into Selective Exposure To Political News, Jisun An, Daniele Quercia, Jon Crowcroft

Research Collection School Of Computing and Information Systems

The hypothesis of selective exposure assumes that people crave like-minded information and eschew information that conflicts with their beliefs, and that has negative consequences on political life. Yet, despite decades of research, this hypothesis remains theoretically promising but empirically difficult to test. We look into news articles shared on Facebook and examine whether selective exposure exists or not in social media. We find a concrete evidence for a tendency that users predominantly share like-minded news articles and avoid conflicting ones, and partisans are more likely to do that. Building tools to counter partisanship on social media would require the ability …


Why Individuals Seek Diverse Opinions (Or Why They Don't), Jisun AN, Daniele QUERCIA, Jon CROWCROFT 2013 Singapore Management University

Why Individuals Seek Diverse Opinions (Or Why They Don't), Jisun An, Daniele Quercia, Jon Crowcroft

Research Collection School Of Computing and Information Systems

Fact checking has been hard enough to do in traditional settings, but, as news consumption is moving on the Internet and sources multiply, it is almost unmanageable. To solve this problem, researchers have created applications that expose people to diverse opinions and, as a result, expose them to balanced information. The wisdom of this solution is, however, placed in doubt by this paper. Survey responses of 60 individuals in the UK and South Korea and in-depth structured interviews of 10 respondents suggest that exposure to diverse opinions would not always work. That is partly because not all individuals equally value …


R-Energy For Evaluating Robustness Of Dynamic Networks, Ming GAO, Ee Peng LIM, David LO 2013 Singapore Management University

R-Energy For Evaluating Robustness Of Dynamic Networks, Ming Gao, Ee Peng Lim, David Lo

Research Collection School Of Computing and Information Systems

The robustness of a network is determined by how well its vertices are connected to one another so as to keep the network strong and sustainable. As the network evolves its robustness changes and may reveal events as well as periodic trend patterns that affect the interactions among users in the network. In this paper, we develop R-energy as a new measure of network robustness based on the spectral analysis of normalized Laplacian matrix. R-energy can cope with disconnected networks, and is efficient to compute with a time complexity of O (jV j + jEj) where V and E are …


Vehicle Localization Along A Previously Driven Route Using An Image Database, Hideyuki KUME, Arne SUPPE, Arne SUPPE 2013 Singapore Management University

Vehicle Localization Along A Previously Driven Route Using An Image Database, Hideyuki Kume, Arne Suppe, Arne Suppe

Research Collection School Of Computing and Information Systems

In most autonomous driving applications, such as parking and commuting, a vehicle follows a previously taken route, or almost the same route. In this paper, we propose a method to localize a vehicle along a previously driven route using images. The proposed method consists of two stages: offline creation of a database, and online localization. In the offline stage, a database is created from images that are captured when the vehicle drives a route for the first time. The database consists of images, 3D positions of feature points estimated by structure-from-motion, and a topological graph. In the online stage, the …


Cost-Sensitive Double Updating Online Learning And Its Application To Online Anomaly Detection, Peilin ZHAO, Steven C. H. HOI 2013 Nanyang Technological University

Cost-Sensitive Double Updating Online Learning And Its Application To Online Anomaly Detection, Peilin Zhao, Steven C. H. Hoi

Research Collection School Of Computing and Information Systems

Although both cost-sensitive classification and online learning have been well studied separately in data mining and machine learning, there was very few comprehensive study of cost-sensitive online classification in literature. In this paper, we formally investigate this problem by directly optimizing cost-sensitive measures for an online classification task. As the first comprehensive study, we propose the Cost-Sensitive Double Updating Online Learning (CSDUOL) algorithms, which explores a recent double updating technique to tackle the online optimization task of cost-sensitive classification by maximizing the weighted sum or minimizing the weighted misclassification cost. We theoretically analyze the cost-sensitive measure bounds of the proposed …


Impact Of Multimedia In Sina Weibo: Popularity And Life Span, Xun ZHAO, Feida ZHU, Weining QIAN, Aoying ZHOU 2013 Singapore Management University

Impact Of Multimedia In Sina Weibo: Popularity And Life Span, Xun Zhao, Feida Zhu, Weining Qian, Aoying Zhou

Research Collection School Of Computing and Information Systems

Multimedia contents such as images and videos are widely used in social network sites nowadays. Sina Weibo, a Chinese microblogging service, is one of the first microblog platforms to incorporate multimedia content sharing features. This work provides statistical analysis on how multimedia contents are produced, consumed, and propagated in Sina Weibo. Based on 230 million tweets and 1.8 million user profiles in Sina Weibo, we study the impact of multimedia contents on the popularity of both users and tweets as well as tweet life span. Our preliminary study shows that multimedia tweets dominant pure text ones in Sina Weibo. Multimedia …


A Secure And Fair Resource Sharing Model For Community Clouds, Santhosh S. Anand 2013 University of Arkansas, Fayetteville

A Secure And Fair Resource Sharing Model For Community Clouds, Santhosh S. Anand

Graduate Theses and Dissertations

Cloud computing has gained a lot of importance and has been one of the most discussed segment of today's IT industry. As enterprises explore the idea of using clouds, concerns have emerged related to cloud security and standardization. This thesis explores whether the Community Cloud Deployment Model can provide solutions to some of the concerns associated with cloud computing. A secure framework based on trust negotiations for resource sharing within the community is developed as a means to provide standardization and security while building trust during resource sharing within the community. Additionally, a model for fair sharing of resources is …


Fans: Face Annotation By Searching Large-Scale Web Facial Images, Steven HOI, Dayong WANG, I Yeu CHENG, Elmer LIN, Jianke ZHU, Ying HE, Chunyan MIAO 2013 Singapore Management University

Fans: Face Annotation By Searching Large-Scale Web Facial Images, Steven Hoi, Dayong Wang, I Yeu Cheng, Elmer Lin, Jianke Zhu, Ying He, Chunyan Miao

Research Collection School Of Computing and Information Systems

Auto face annotation is an important technique for many real-world applications, such as online photo album management, new video summarization, and so on. It aims to automatically detect human faces from a photo image and further name the faces with the corresponding human names. Recently, mining web facial images on the internet has emerged as a promising paradigm towards auto face annotation. In this paper, we present a demonstration system of search-based face annotation: FANS - Face ANnotation by Searching large-scale web facial images. Given a query facial image for annotation, we first retrieve a short list of the most …


Your Love Is Public Now: Questioning The Use Of Personal Information In Authentication, Payas GUPTA, Swapna GOTTIPATI, Jing JIANG, Debin GAO 2013 Singapore Management University

Your Love Is Public Now: Questioning The Use Of Personal Information In Authentication, Payas Gupta, Swapna Gottipati, Jing Jiang, Debin Gao

Research Collection School Of Computing and Information Systems

Most social networking platforms protect user's private information by limiting access to it to a small group of members, typically friends of the user, while allowing (virtually) everyone's access to the user's public data. In this paper, we exploit public data available on Facebook to infer users' undisclosed interests on their profile pages. In particular, we infer their undisclosed interests from the public data fetched using Graph APIs provided by Facebook. We demonstrate that simply liking a Facebook page does not corroborate that the user is interested in the page. Instead, we perform sentiment-oriented mining on various attributes of a …


It Is Not Just What We Say, But How We Say Them: Lda-Based Behavior-Topic Model, Minghui QIU, Feida ZHU, Jing JIANG 2013 Singapore Management University

It Is Not Just What We Say, But How We Say Them: Lda-Based Behavior-Topic Model, Minghui Qiu, Feida Zhu, Jing Jiang

Research Collection School Of Computing and Information Systems

Textual information exchanged among users on online social network platforms provides deep understanding into users' interest and behavioral patterns. However, unlike traditional text-dominant settings such as o ine publishing, one distinct feature for online social network is users' rich interactions with the textual content, which, unfortunately, has not yet been well incorporated in the existing topic modeling frameworks. In this paper, we propose an LDA-based behavior-topic model (B-LDA) which jointly models user topic interests and behavioral patterns. We focus the study of the model on online social network settings such as microblogs like Twitter where the textual content is relatively …


Digital Commons powered by bepress