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Full-Text Articles in Physical Sciences and Mathematics

Querie: Collaborative Database Exploration, Magdalini Eirinaki, Suju Abraham, Neoklis Polyzotis, Naushin Shaikh Jul 2014

Querie: Collaborative Database Exploration, Magdalini Eirinaki, Suju Abraham, Neoklis Polyzotis, Naushin Shaikh

Magdalini Eirinaki

Interactive database exploration is a key task in information mining. However, users who lack SQL expertise or familiarity with the database schema face great difficulties in performing this task. To aid these users, we developed the QueRIE system for personalized query recommendations. QueRIE continuously monitors the user’s querying behavior and finds matching patterns in the system’s query log, in an attempt to identify previous users with similar information needs. Subsequently, QueRIE uses these “similar” users and their queries to recommend queries that the current user may find interesting. In this work we describe an instantiation of the QueRIE framework, where …


Robust Course-Boundary Extraction Algorithms For Autonomous Vehicles, Chris Roman, Charles Reinholtz Jan 2013

Robust Course-Boundary Extraction Algorithms For Autonomous Vehicles, Chris Roman, Charles Reinholtz

Christopher N. Roman

Practical autonomous robotic vehicles require dependable methods for accurately identifying course or roadway boundaries. The authors have developed a method to reliably extract the boundary line using simple dynamic thresholding, noise filtering, and blob removal. This article describes their efforts to apply this procedure in developing an autonomous vehicle.


Autonomous Underwater Vehicles As Tools For Deep-Submergence Archaeology, Christopher N. Roman, Ian Roderick Mather Jan 2013

Autonomous Underwater Vehicles As Tools For Deep-Submergence Archaeology, Christopher N. Roman, Ian Roderick Mather

Christopher N. Roman

Marine archaeology beyond the capabilities of scuba divers is a technologically enabled field. The tool suite includes ship-based systems such as towed side-scan sonars and remotely operated vehicles, and more recently free-swimming autonomous underwater vehicles (AUVs). Each of these platforms has various imaging and mapping capabilities appropriate for specific scales and tasks. Broadly speaking, AUVs are becoming effective tools for locating, identifying, and surveying archaeological sites. This paper discusses the role of AUVs in this suite of tools, outlines some specific design criteria necessary to maximize their utility in the field, and presents directions for future developments. Results are presented …


Variable Morphologic Expression Of Volcanic, Tectonic, And Hydrothermal Processes At Six Hydrothermal Vent Fields In The Lau Back-Arc Basin, Vicki Lynn Ferrini, Margaret K. Tivey, Suzanne M. Carbotte, Fernando Martinez, Chris Roman Dec 2012

Variable Morphologic Expression Of Volcanic, Tectonic, And Hydrothermal Processes At Six Hydrothermal Vent Fields In The Lau Back-Arc Basin, Vicki Lynn Ferrini, Margaret K. Tivey, Suzanne M. Carbotte, Fernando Martinez, Chris Roman

Christopher N. Roman

Ultrahigh-resolution bathymetric maps (25 cm grid) are used to quantify the physical dimensions of and spatial relationships between tectonic, volcanic, and hydrothermal features at six hydrothermal vent fields in the Lau back-arc basin. Supplemented with near-bottom photos, and nested within regional DSL-120A side-scan sonar data, these maps provide insight into the nature of hydrothermal systems along the Eastern Lau Spreading Center (ELSC) and Valu Fa Ridge (VFR). Along-axis transitions evident in localized volcanic morphology and tectonic characteristics include a change from broad low-relief volcanic domes (hundreds of meters wide,tall) that are dominated by pillow and lobate lava morphologies and are …


Concept Tests For A New Wire Flying Vehicle Designed To Achieve High Horizontal Resolution Profiling In Deep Water, Chris Roman, Dave Hebert Dec 2012

Concept Tests For A New Wire Flying Vehicle Designed To Achieve High Horizontal Resolution Profiling In Deep Water, Chris Roman, Dave Hebert

Christopher N. Roman

Efficiently profiling the water column to achieve both high vertical and horizontal resolution from a moving vessel in deep water is difficult. Current solutions, such as CTD tow-yos, moving vessel profilers, and undulating tow bodies, are limited by ship speed or water depth. As a consequence, it is difficult to obtain oceanographic sections with sufficient resolution to identify many relevant scales over the deeper sections of the water column. This paper presents a new concept for a profiling vehicle that slides up and down a towed wire in a controlled manner using the lift created by wing foils. The wings …


Feature-Based Opinion Mining And Ranking, Magdalini Eirinaki, S. Pisal, J. Singh Jul 2012

Feature-Based Opinion Mining And Ranking, Magdalini Eirinaki, S. Pisal, J. Singh

Magdalini Eirinaki

The proliferation of blogs and social networks presents a new set of challenges and opportunities in the way information is searched and retrieved. Even though facts still play a very important role when information is sought on a topic, opinions have become increasingly important as well. Opinions expressed in blogs and social networks are playing an important role influencing everything from the products people buy to the presidential candidate they support. Thus, there is a need for a new type of search engine which will not only retrieve facts, but will also enable the retrieval of opinions. Such a search …


Identification Of Influential Social Networkers, Magdalini Eirinaki, S. P. Singh Monga, S. Sundaram Jan 2012

Identification Of Influential Social Networkers, Magdalini Eirinaki, S. P. Singh Monga, S. Sundaram

Magdalini Eirinaki

Online social networking is deeply interleaved in today's lifestyle. People come together and build communities to share thoughts, offer suggestions, exchange information, ideas, and opinions. Moreover, social networks often serve as platforms for information dissemination and product placement or promotion through viral marketing. The success rate in this type of marketing could be increased by targeting specific individuals, called 'influential users', having the largest possible reach within an online community. In this paper, we present a method aiming at identifying the influential users within an online social networking application. We introduce ProfileRank, a metric that uses popularity and activity characteristics …


Generation Of Isolated Attosecond Extreme Ultraviolet Pulses: Optimization Of Coupled Ellipsoids, Sarah L. Stebbings, F. Süßmann, Y-Y Yang, A. Scrinzi, Maxim Durach, Anastasia Rusina, Mark I. Stockman, Matthias F. Kling Jan 2011

Generation Of Isolated Attosecond Extreme Ultraviolet Pulses: Optimization Of Coupled Ellipsoids, Sarah L. Stebbings, F. Süßmann, Y-Y Yang, A. Scrinzi, Maxim Durach, Anastasia Rusina, Mark I. Stockman, Matthias F. Kling

Maxim Durach

The production of extreme ultraviolet (XUV) radiation via nanoplasmonic field-enhanced high-harmonic generation (HHG) in gold nanostructures at MHz repetition rates is investigated theoretically in this paper. Analytical and numerical calculations are employed and compared in order to determine the plasmonic fields in gold ellipsoidal nanoparticles. The comparison indicates that numerical calculations can accurately predict the field enhancement and plasmonic decay, but may encounter difficulties when attempting to predict the oscillatory behavior of the plasmonic field. Numerical calculations for coupled symmetric and asymmetric ellipsoids for different carrier-envelope phases (CEPs) of the driving laser field are combined with time-dependent Schrödinger equation simulations …


Metallization Of Nanofilms In Strong Adiabatic Electric Fields, Maxim Durach, Anastasia Rusina, Matthias F. Kling, Mark I. Stockman Jan 2010

Metallization Of Nanofilms In Strong Adiabatic Electric Fields, Maxim Durach, Anastasia Rusina, Matthias F. Kling, Mark I. Stockman

Maxim Durach

We introduce an effect of metallization of dielectric nanofilms by strong, adiabatically varying electric fields. The metallization causes optical properties of a dielectric film to become similar to those of a plasmonic metal (strong absorption and negative permittivity at low optical frequencies). This is a quantum effect, which is exponentially size-dependent, occurring at fields on the order of 0.1  V/Å and pulse durations ranging from ∼1  fs to ∼10  ns for a film thickness of 3–10 nm.


Mining Frequent Generalized Patterns For Web Personalization In The Presence Of Taxonomies, Panagiotis Giannikopoulos, Iraklis Varlamis, Magdalini Eirinaki Jan 2010

Mining Frequent Generalized Patterns For Web Personalization In The Presence Of Taxonomies, Panagiotis Giannikopoulos, Iraklis Varlamis, Magdalini Eirinaki

Magdalini Eirinaki

The Web is a continuously evolving environment, since its content is updated on a regular basis. As a result, the traditional usage-based approach to generate recommendations that takes as input the navigation paths recorded on the Web page level, is not as effective. Moreover, most of the content available online is either explicitly or implicitly characterized by a set of categories organized in a taxonomy, allowing the page-level navigation patterns to be generalized to a higher, aggregate level. In this direction, the authors present the Frequent Generalized Pattern (FGP) algorithm. FGP takes as input the transaction data and a hierarchy …


Web Site Personalization Based On Link Analysis And Navigational Patterns, Magdalini Eirinaki, Michalis Vazirgiannis Oct 2007

Web Site Personalization Based On Link Analysis And Navigational Patterns, Magdalini Eirinaki, Michalis Vazirgiannis

Magdalini Eirinaki

The continuous growth in the size and use of the World Wide Web imposes new methods of design and development of online information services. The need for predicting the users' needs in order to improve the usability and user retention of a Web site is more than evident and can be addressed by personalizing it. Recommendation algorithms aim at proposing “next” pages to users based on their current visit and past users' navigational patterns. In the vast majority of related algorithms, however, only the usage data is used to produce recommendations, disregarding the structural properties of the Web graph. Thus …


Web Mining For Web Personalization, Magdalini Eirinaki, Michalis Vazirgiannis Feb 2003

Web Mining For Web Personalization, Magdalini Eirinaki, Michalis Vazirgiannis

Magdalini Eirinaki

Web personalization is the process of customizing a Web site to the needs of specific users, taking advantage of the knowledge acquired from the analysis of the user's navigational behavior (usage data) in correlation with other information collected in the Web context, namely, structure, content, and user profile data. Due to the explosive growth of the Web, the domain of Web personalization has gained great momentum both in the research and commercial areas. In this article we present a survey of the use of Web mining for Web personalization. More specifically, we introduce the modules that comprise a Web personalization …