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Articles 1051 - 1080 of 2813

Full-Text Articles in Physical Sciences and Mathematics

Global Dimension Of Ci: Compete Or Collaborate, Arden L. Bement Jr. Dec 2010

Global Dimension Of Ci: Compete Or Collaborate, Arden L. Bement Jr.

PPRI Digital Library

No abstract provided.


Network Science: Using Information Technology To Enable Collaboration, Arden L. Bement Jr. Dec 2010

Network Science: Using Information Technology To Enable Collaboration, Arden L. Bement Jr.

PPRI Digital Library

No abstract provided.


Endogenous Sirnas And Noncoding Rna-Derived Small Rnas Are Expressed In Adult Mouse Hippocampus And Are Up-Regulated In Olfactory Discrimination Training., Neil Smalheiser, G Lugli, Jyothi Thimmapuram, E.H. Cook, J Larson Nov 2010

Endogenous Sirnas And Noncoding Rna-Derived Small Rnas Are Expressed In Adult Mouse Hippocampus And Are Up-Regulated In Olfactory Discrimination Training., Neil Smalheiser, G Lugli, Jyothi Thimmapuram, E.H. Cook, J Larson

Cyber Center Publications

We previously proposed that endogenous siRNAs may regulate synaptic plasticity and long-term gene expression in the mammalian brain. Here, a hippocampal-dependent task was employed in which adult mice were trained to execute a nose-poke in a port containing one of two simultaneously present odors in order to obtain a reward. Mice demonstrating olfactory discrimination training were compared to pseudo-training and nose-poke control groups; size-selected hippocampal RNA was subjected to Illumina deep sequencing. Sequences that aligned uniquely and exactly to the genome without uncertain nucleotide assignments, within exons or introns of MGI annotated genes, were examined further. The data confirm that …


Increasing Effectiveness Of The Zachman Framework Using The Balanced Scorecard, Anagha Gokhale Aug 2010

Increasing Effectiveness Of The Zachman Framework Using The Balanced Scorecard, Anagha Gokhale

Purdue Polytechnic Masters Theses

The purpose of this study is to explore the impact of integrating the use of Zachman Framework of Enterprise Architecture and the Balanced Scorecard (BSC) Framework for an effective business-IT alignment. The study tries to identify certain gaps in the Zachman Framework focusing on the motivational aspects of the framework, which have been discussed in the literature review. The aim is to achieve the integration by mitigating these motivational aspect’s weaknesses in the Zachman Framework using the deliverables obtained from the BSC. Thus the author proposes to achieve business-IT alignment through this integration. No research studies in the past have …


A Visual Analytics Approach To Understanding Spatiotemporal Hotspots, Ross Maciejewski, Stephen Rudolph, Ryan Hafen, Ahmad Abusalah, Mohamed Yakout, Mourad Ouzzani, William S. Cleveland, Shaun Grannis, David S. Ebert Jan 2010

A Visual Analytics Approach To Understanding Spatiotemporal Hotspots, Ross Maciejewski, Stephen Rudolph, Ryan Hafen, Ahmad Abusalah, Mohamed Yakout, Mourad Ouzzani, William S. Cleveland, Shaun Grannis, David S. Ebert

Cyber Center Publications

As data sources become larger and more complex, the ability to effectively explore and analyze patterns amongst varying sources becomes a critical bottleneck in analytic reasoning. Incoming data contains multiple variables, high signal to noise ratio, and a degree of uncertainty, all of which hinder exploration, hypothesis eneration/exploration, and decision making. To facilitate the exploration of such data, advanced tool sets are needed that allow the user to interact with their data in a visual environment that provides direct analytic capability for finding data aberrations or hotspots. In this paper, we present a suite of tools designed to facilitate the …


A Database Server For Next-Generation Scientific Data Management, Mohamed Eltabakh, Walid G. Aref, Ahmed Elmagarmid Jan 2010

A Database Server For Next-Generation Scientific Data Management, Mohamed Eltabakh, Walid G. Aref, Ahmed Elmagarmid

Cyber Center Publications

The growth of scientific information and the increasing automation of data collection have made databases integral to many scientific disciplines including life sciences, physics, meteorology, earth and atmospheric sciences, and chemistry. These sciences pose new data management challenges to current database system technologies. This dissertation addresses the following three challenges: (1) Annotation Management: Annotations and provenance information are important metadata that go hand-in-hand with scientific data. Annotating scientific data represents a vital mechanism for scientists to share knowledge and build an interactive and collaborative environment. A major challenge is: How to manage large volumes of annotations, especially at various granularities, …


Spatio-Temporal Access Methods: Part 2 (2003 - 2010), Long-Van Nguyen-Dinh, Walid G. Aref, Mohamed Mokbel Jan 2010

Spatio-Temporal Access Methods: Part 2 (2003 - 2010), Long-Van Nguyen-Dinh, Walid G. Aref, Mohamed Mokbel

Cyber Center Publications

In spatio-temporal applications, moving objects detect their locations via location-aware devices and update their locations continuously to the server. With the ubiquity and massive numbers of moving objects, many spatio-temporal access methods are developed to process user queries efficiently. Spatio- temporal access methods are classified into four categories: (1) Indexing the past data, (2) Indexing the current data, (3) Indexing the future data, and (4) Indexing data at all points of time. This short survey is Part 2 of our previous work [28]. In Part 2, we give an overview and classification of spatio-temporal access methods that are published between …


Privometer: Privacy Protection In Social Networks, Nilothpal Talukder, Mourad Ouzzani, Ahmed Elmagarmid, Hazem Elmeleegy Jan 2010

Privometer: Privacy Protection In Social Networks, Nilothpal Talukder, Mourad Ouzzani, Ahmed Elmagarmid, Hazem Elmeleegy

Cyber Center Publications

The increasing popularity of social networks, such as Facebook and Orkut, has raised several privacy concerns. Traditional ways of safeguarding privacy of personal information by hiding sensitive attributes are no longer adequate. Research shows that probabilistic classification techniques can effectively infer such private information. The disclosed sensitive information of friends, group affiliations and even participation in activities, such as tagging and commenting, are considered background knowledge in this process. In this paper, we present a privacy protection tool, called Privometer, that measures the amount of sensitive information leakage in a user profile and suggests selfsanitization actions to regulate the amount …


Identifying Interesting Instances For Probabilistic Skylines, Yinian Qi, Mikhail J. Atallah Dec 2009

Identifying Interesting Instances For Probabilistic Skylines, Yinian Qi, Mikhail J. Atallah

Department of Computer Science Technical Reports

No abstract provided.


Lower Tropospheric Temperature Variability Over The Usa: A Gis Approach, Souleymane Fall, Dev Niyogi, Gilbert L. Rochon Nov 2009

Lower Tropospheric Temperature Variability Over The Usa: A Gis Approach, Souleymane Fall, Dev Niyogi, Gilbert L. Rochon

GIS Day

We use the high resolution North American Regional Analysis (NARR) dataset to build for the United States a Temperature Change Index (TCI) based on four contributing variables derived from the layer-averaged temperature and lapse rate of the 1000mb - 700mb layer (near-surface to 3000 meters) for the 1979-2008 period. The analysis uses Geographic Information Systems (GIS) methods to identify distinct regional patterns based on aggregate temperature trends and variability scores. The resulting index allows us to identify and compare regions that experience high (low) temperature trends and variability that are referred to as hot spots (cold spots). The upper Midwest …


Mash-Ups In Abe Models, And The New Epa Waters Web Services, Larry Theller Nov 2009

Mash-Ups In Abe Models, And The New Epa Waters Web Services, Larry Theller

GIS Day

Documents recent efforts to integrate Purdue's Long-Term Hydrologic Impact Assessment (L-THIA) land use change model with data from Purdue, USEPA, and Michigan State’s Institute of Water Research within Google Maps


Ballistic-Ohmic Quantum Hall Plateau Transition In A Graphene P-N Junction, Tony Low Nov 2009

Ballistic-Ohmic Quantum Hall Plateau Transition In A Graphene P-N Junction, Tony Low

Birck and NCN Publications

Recent quantum Hall experiments conducted on disordered graphene p-n junction provide evidence that the junction resistance could be described by a simple Ohmic sum of the n and p mediums’ resistances. However in the ballistic limit, theory predicts the existence of chirality-dependent quantum Hall plateaus in a p-n junction. We show that two distinctively separate processes are required for this ballistic-Ohmic plateau transition, namely, (i) hole/electron Landau states mixing and (ii) valley isospin dilution of the incident Landau edge state. These conclusions are obtained by a simple scattering theory argument, and confirmed numerically by performing ensembles of quantum magnetotransport calculations …


Instability In Leapfrog And Forward–Backward Schemes, Wen-Yih Sun Nov 2009

Instability In Leapfrog And Forward–Backward Schemes, Wen-Yih Sun

Department of Earth, Atmospheric, and Planetary Sciences Faculty Publications

No abstract provided.


Electronic Transport Properties Of A Tilted Graphene P-N Junction, Tony Low, Joerg Appenzeller Oct 2009

Electronic Transport Properties Of A Tilted Graphene P-N Junction, Tony Low, Joerg Appenzeller

Birck and NCN Publications

Spatial manipulation of current flow in graphene could be achieved through the use of a tilted p-n junction. We show through numerical simulation that a pseudo-Hall effect (i.e., nonequilibrium charge and current density accumulating along one of the sides of a graphene ribbon) can be observed under these conditions. The tilt angle and the p-n transition length are two key parameters in tuning the strength of this effect. This phenomenon can be explained using classical trajectory via ray analysis, and is therefore relatively robust against disorder. Lastly, we propose and simulate a three terminal device that allows direct experimental access …


A Statistical Method For Integrated Data Cleaning And Imputation, Chris Mayfield, Jennifer Neville, Sunil Prabhakar Sep 2009

A Statistical Method For Integrated Data Cleaning And Imputation, Chris Mayfield, Jennifer Neville, Sunil Prabhakar

Department of Computer Science Technical Reports

No abstract provided.


Homomorphic Encryption Based K-Out-Of-N Oblivious Transfer Protocols, Mummoorthy Murugesan, Wei Jiang, Erhan Nergiz, Serkan Uzunbaz Sep 2009

Homomorphic Encryption Based K-Out-Of-N Oblivious Transfer Protocols, Mummoorthy Murugesan, Wei Jiang, Erhan Nergiz, Serkan Uzunbaz

Department of Computer Science Technical Reports

No abstract provided.


Strain Energy And Lateral Friction Force Distributions Of Carbon Nanotubes Manipulated Into Shapes By Atomic Force Microscopy, Mark C. Strus, Roya R. Lahiji, Pablo Ares, Vincente Lopez, Arvind Raman, Ron R. Reifenberger Aug 2009

Strain Energy And Lateral Friction Force Distributions Of Carbon Nanotubes Manipulated Into Shapes By Atomic Force Microscopy, Mark C. Strus, Roya R. Lahiji, Pablo Ares, Vincente Lopez, Arvind Raman, Ron R. Reifenberger

Other Nanotechnology Publications

The interplay between local mechanical strain energy and lateral frictional forces determines the shape of carbon nanotubes on substrates. In turn, because of its nanometer-size diameter, the shape of a carbon nanotube strongly influences its local electronic, chemical, and mechanical properties. Few, if any, methods exist for resolving the strain energy and static frictional forces along the length of a deformed nanotube supported on a substrate. We present a method using nonlinear elastic rod theory in which we compute the flexural strain energy and static frictional forces along the length of single walled carbon nanotubes (SWCNTs) manipulated into various shapes …


Online Piece-Wise Linear Approximation Of Numerical Streams With Precision Guarantees, Hazem Elmeleegy, Ahmed Elmagarmid, Emmanuel Cecchet, Walid G. Aref, Willy Zwaenepoel Aug 2009

Online Piece-Wise Linear Approximation Of Numerical Streams With Precision Guarantees, Hazem Elmeleegy, Ahmed Elmagarmid, Emmanuel Cecchet, Walid G. Aref, Willy Zwaenepoel

Cyber Center Publications

Continuous “always-on” monitoring is beneficial for a number of applications, but potentially imposes a high load in terms of communication, storage and power consumption when a large number of variables need to be monitored. We introduce two new filtering techniques, swing filters and slide filters, that represent within a prescribed precision a time-varying numerical signal by a piecewise linear function, consisting of connected line segments for swing filters and (mostly) disconnected line segments for slide filters. We demonstrate the effectiveness of swing and slide filters in terms of their compression power by applying them to a reallife data set plus …


Diversity And Strain Specificity Of Plant Cell Wall Degrading Enzymes Revealed By The Draft Genome Of Ruminococcus Flavefaciens Fd-1, Margret E. Berg Miller, Dionysios A. Antonopoulos, Mark Brand, Albert Bari, Alvaro Hernandez, Jyothi Thimmapuram, Bryan A. White, Marco Rincon, Harry J. Flint, Bernard Henrissat, Pedro M. Coutinho Aug 2009

Diversity And Strain Specificity Of Plant Cell Wall Degrading Enzymes Revealed By The Draft Genome Of Ruminococcus Flavefaciens Fd-1, Margret E. Berg Miller, Dionysios A. Antonopoulos, Mark Brand, Albert Bari, Alvaro Hernandez, Jyothi Thimmapuram, Bryan A. White, Marco Rincon, Harry J. Flint, Bernard Henrissat, Pedro M. Coutinho

Cyber Center Publications

Ruminococcus flavefaciens is a predominant cellulolytic rumen bacterium, which forms a multi-enzyme cellulosome complex that could play an integral role in the ability of this bacterium to degrade plant cell wall polysaccharides. Identifying the major enzyme types involved in plant cell wall degradation is essential for gaining a better understanding of the cellulolytic capabilities of this organism as well as highlighting potential enzymes for application in improvement of livestock nutrition and for conversion of cellulosic biomass to liquid fuels.


Non-Pinhole Imposters, Voicu Popescu, Kyle Hayward, Paul Rosen, Chris Wyman Aug 2009

Non-Pinhole Imposters, Voicu Popescu, Kyle Hayward, Paul Rosen, Chris Wyman

Department of Computer Science Technical Reports

No abstract provided.


A Network-Aware Distributed Membership Protocol For Collaborative Defense, David Zage, Carl Livadas, Eve M. Schooler May 2009

A Network-Aware Distributed Membership Protocol For Collaborative Defense, David Zage, Carl Livadas, Eve M. Schooler

Department of Computer Science Technical Reports

No abstract provided.


On The Modification Of An Eigenvalue Problem That Preserves An Eigenspace, Maxim Maumov Apr 2009

On The Modification Of An Eigenvalue Problem That Preserves An Eigenspace, Maxim Maumov

Department of Computer Science Technical Reports

No abstract provided.


Supporting Real-World Activities In Database Management Systems, Mohamed Eltabakh, Walid G. Aref, Ahmed K. Elmagarmid, Yasin Laura-Silva, Mourad Ouzzani Mar 2009

Supporting Real-World Activities In Database Management Systems, Mohamed Eltabakh, Walid G. Aref, Ahmed K. Elmagarmid, Yasin Laura-Silva, Mourad Ouzzani

Department of Computer Science Technical Reports

No abstract provided.


Generalization Of Acid Properties, Brahim Medjahed, Mourad Ouzzani, Ahmed Elmagarmid Jan 2009

Generalization Of Acid Properties, Brahim Medjahed, Mourad Ouzzani, Ahmed Elmagarmid

Cyber Center Publications

ACID (Atomicity, Consistency, Isolation, and Durability) is a set of properties that guarantee the reliability of database transactions [2]. ACID properties were initially developed with traditional, business-oriented applications (e.g., banking) in mind. Hence, they do not fully support the functional and performance requirements of advanced database applications such as computer-aided design, computer-aided manufacturing, office automation, network management, multidatabases, and mobile databases. For instance, transactions in computer-aided design applications are generally of long duration and preserving the traditional ACID properties in such transactions would require locking resources for long periods of time. This has lead to the generalization of ACID properties …


Beyond K-Anonymity: A Decision Theoretic Framework For Assessing Privacy Risk, Guy Lebanon, Monica Scannapieco, Mohamed Fouad, Elisa Bertino Jan 2009

Beyond K-Anonymity: A Decision Theoretic Framework For Assessing Privacy Risk, Guy Lebanon, Monica Scannapieco, Mohamed Fouad, Elisa Bertino

Cyber Center Publications

An important issue any organization or individual has to face when managing data containing sensitive information, is the risk that can be incurred when releasing such data. Even though data may be sanitized before being released, it is still possible for an adversary to reconstruct the original data using additional information thus resulting in privacy violations. To date, however, a systematic approach to quantify such risks is not available. In this paper we develop a framework, based on statistical decision theory, that assesses the relationship between the disclosed data and the resulting privacy risk. We model the problem of deciding …


Query Mesh: Multiroute, Rimma Nehme, Karen Works, Elke Rundensteiner, Elisa Bertino Jan 2009

Query Mesh: Multiroute, Rimma Nehme, Karen Works, Elke Rundensteiner, Elisa Bertino

Cyber Center Publications

We propose to demonstrate a practical alternative approach to the current state-of-the-art query processing techniques, called the “Query Mesh” (or QM, for short). The main idea of QM is to compute multiple routes (i.e., query plans)1, each designed for a particular subset of data with distinct statistical properties. Based on the execution routes and the data characteristics, a classifier model is induced and is used to partition new data tuples to assign the best routes for their processing. We propose to demonstrate the QM framework in the streaming context using our demo application, called the “Ubi-City”. We will illustrate the …


Protein-Protein Docking Using Region-Based 3d Zernike Descriptors., Vishwesh Venkatraman, Yifeng D. Yang, Lee Sael, Daisuke Kihara Jan 2009

Protein-Protein Docking Using Region-Based 3d Zernike Descriptors., Vishwesh Venkatraman, Yifeng D. Yang, Lee Sael, Daisuke Kihara

Department of Biological Sciences Faculty Publications

Background

Protein-protein interactions are a pivotal component of many biological processes and mediate a variety of functions. Knowing the tertiary structure of a protein complex is therefore essential for understanding the interaction mechanism. However, experimental techniques to solve the structure of the complex are often found to be difficult. To this end, computational protein-protein docking approaches can provide a useful alternative to address this issue. Prediction of docking conformations relies on methods that effectively capture shape features of the participating proteins while giving due consideration to conformational changes that may occur.

Results

We present a novel protein docking algorithm based …


A Hierarchical Approach To Model Web Query Interfaces For Web Source Integration, Thomas Kabisch, Eduard Dragut, Clement Yu, Ulf Leser Jan 2009

A Hierarchical Approach To Model Web Query Interfaces For Web Source Integration, Thomas Kabisch, Eduard Dragut, Clement Yu, Ulf Leser

Cyber Center Publications

Much data in the Web is hidden behind Web query interfaces. In most cases the only means to "surface" the content of a Web database is by formulating complex queries on such interfaces. Applications such as Deep Web crawling and Web database integration require an automatic usage of these interfaces. Therefore, an important problem to be addressed is the automatic extraction of query interfaces into an appropriate model. We hypothesize the existence of a set of domain-independent "commonsense design rules" that guides the creation of Web query interfaces. These rules transform query interfaces into schema trees. In this paper we …


Private Queries And Trajectory Anonymization: A Dual Perspective On Location Privacy, Gabriel Ghinita Jan 2009

Private Queries And Trajectory Anonymization: A Dual Perspective On Location Privacy, Gabriel Ghinita

Cyber Center Publications

The emergence of mobile devices with Internet connectivity (e.g., Wi-Fi) and global positioning capabilities (e.g., GPS) have triggered the widespread development of location-based applications. For instance, users are able to ask queries about points of interest in their proximity. Furthermore, users can act as mobile sensors to monitor traffic flow, or levels of air pollution. However, such applications require users to disclose their locations, which raises serious privacy concerns. With knowledge of user locations, a malicious attacker can infer sensitive information, such as alternative lifestyles or political affiliations. Preserving location privacy is an essential requirement towards the successful deployment of …


The Plant Ionome Coming Into Focus, Lorraine Williams, David Salt Jan 2009

The Plant Ionome Coming Into Focus, Lorraine Williams, David Salt

Cyber Center Publications

92 elements have been identified on earth and 17 of these are known to be essential to all plants. The essential elements required in relatively large amounts (>0.1% of dry mass) are called macronutrients and include C, H, O, N, S, P, Ca, K, Mg. Those required in much smaller amounts (<0.01% of dry mass) are referred to as micronutrients or trace elements and include Ni, Mo, Cu, Zn, Mn, B, Fe, and Cl. Plant growth and development depends on a balanced supply of these essential elements and thus the plant has a range of homeostatic mechanisms operating to ensure that this is maintained. Beneficial elements which promote growth and may be essential to some taxa, include Na, Co, Al, Se and Si. Elements such as the heavy metal Cd and the metalloid As have no demonstrated biological function in plants, but are nevertheless taken up and cause severe toxicity in most plant species. The concept for this special issue is the plant ionome, a word coined to encompass all these elements and allow focussed discussion and investigations on the mechanisms that co-ordinately regulate these elements in response to genetic and environmental factors reviewed in Salt et al., 2008).