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2013

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Articles 181 - 210 of 11461

Full-Text Articles in Physical Sciences and Mathematics

Designing Optimal Innovation Portfolio, Arcot Desai Narasimhalu Dec 2013

Designing Optimal Innovation Portfolio, Arcot Desai Narasimhalu

Research Collection School Of Computing and Information Systems

There have been many approaches towards investing in innovation projects. There has been very little discussion about the need to align such investments with the mission, vision, goals, leadership style, value discipline and risk appetite of an organization. This paper reviews existing approaches to innovation related investments and suggests the setting up of a proper innovation portfolio management process along with three dashboards that will help make innovation related investment decisions in an informed manner. The resulting innovation portfolio will be optimal in its alignment with an organizations mission and vision. We expect this method to be used by all …


Causal Mediation In A Survival Setting With Time-Dependent Mediators, Wenjing Zheng, Mark J. Van Der Laan Dec 2013

Causal Mediation In A Survival Setting With Time-Dependent Mediators, Wenjing Zheng, Mark J. Van Der Laan

Wenjing Zheng

The effect of an expsore on an outcome of interest is often mediated by intermediate variables. The goal of causal mediation analysis is to evaluate the role of these intermediate variables (mediators) in the causal effect of the exposure on the outcome. In this paper, we consider causal mediation of a baseline exposure on a survival (or time-to-event) outcome, when the mediator is time-dependent. The challenge in this setting lies in that the event process takes places jointly with the mediator process; in particular, the length of the mediator history depends on the survival time. As a result, we argue …


Targeted Maximum Likelihood Estimation Of Natural Direct Effect, Wenjing Zheng, Mark Van Der Laan Dec 2013

Targeted Maximum Likelihood Estimation Of Natural Direct Effect, Wenjing Zheng, Mark Van Der Laan

Wenjing Zheng

In many causal inference problems, one is interested in the direct causal effect of an exposure on an outcome of interest that is not mediated by certain intermediate variables. Robins and Greenland (1992) and Pearl (2000) formalized the definition of two types of direct effects (natural and controlled) under the counterfactual framework. Since then, identifiability conditions for these effects have been studied extensively. By contrast, considerably fewer efforts have been invested in the estimation problem of the natural direct effect. In this article, we propose a semiparametric efficient, multiply robust estimator for the natural direct effect of a binary treatment …


Synthesizing Population, Health, And Place, Martin Raubal, Geoffrey Jacquez, John Wilson, Werner Kuhn Dec 2013

Synthesizing Population, Health, And Place, Martin Raubal, Geoffrey Jacquez, John Wilson, Werner Kuhn

Journal of Spatial Information Science

No abstract provided.


An Interactive Bibliography On Temporal Gis, Willington Siabato, Christophe Claramunt, Miguel Ángel Bernabé-Poveda Dec 2013

An Interactive Bibliography On Temporal Gis, Willington Siabato, Christophe Claramunt, Miguel Ángel Bernabé-Poveda

Journal of Spatial Information Science

No abstract provided.


Formalizing Spatiotemporal Knowledge In Remote Sensing Applications To Improve Image Interpretation, Christelle Pierkot, Samuel Andrés, Jean François Faure, Frédérique Seyler Dec 2013

Formalizing Spatiotemporal Knowledge In Remote Sensing Applications To Improve Image Interpretation, Christelle Pierkot, Samuel Andrés, Jean François Faure, Frédérique Seyler

Journal of Spatial Information Science

Technological tools allow the generation of large volumes of data. For example satellite images aid in the study of spatiotemporal phenomena in a range of disciplines such as urban planning environmental sciences and health care. Thus remote-sensing experts must handle various and complex image sets for their interpretations. The GIS community has undertaken significant work in describing spatiotemporal features and standard specifications nowadays provide design foundations for GIS software and spatial databases. We argue that this spatiotemporal knowledge and expertise would provide invaluable support for the field of image interpretation. As a result we propose a high level conceptual framework …


Multi-Scale Window Specification Over Streaming Trajectories, Kostas Patroumpas Dec 2013

Multi-Scale Window Specification Over Streaming Trajectories, Kostas Patroumpas

Journal of Spatial Information Science

Enormous amounts of positional information are collected by monitoring applications in domains such as fleet management cargo transport wildlife protection etc. With the advent of modern location-based services processing such data mostly focuses on providing real-time response to a variety of user requests in continuous and scalable fashion. An important class of such queries concerns evolving trajectories that continuously trace the streaming locations of moving objects like GPS-equipped vehicles commodities with RFID's people with smartphones etc. In this work we propose an advanced windowing operator that enables online incremental examination of recent motion paths at multiple resolutions for numerous point …


The Semantic Similarity Ensemble, Andrea Ballatore, Michela Bertolotto, David C. Wilson Dec 2013

The Semantic Similarity Ensemble, Andrea Ballatore, Michela Bertolotto, David C. Wilson

Journal of Spatial Information Science

Computational measures of semantic similarity between geographic terms provide valuable support across geographic information retrieval data mining and information integration. To date a wide variety of approaches to geo-semantic similarity have been devised. A judgment of similarity is not intrinsically right or wrong but obtains a certain degree of cognitive plausibility depending on how closely it mimics human behavior. Thus selecting the most appropriate measure for a specific task is a significant challenge. To address this issue we make an analogy between computational similarity measures and soliciting domain expert opinions which incorporate a subjective set of beliefs perceptions hypotheses and …


Semantic And Conceptual Issues In Geographic Information Systems, Eliseo Clementini, Esteban Zimanyi Dec 2013

Semantic And Conceptual Issues In Geographic Information Systems, Eliseo Clementini, Esteban Zimanyi

Journal of Spatial Information Science

No abstract provided.


Testing Ogc Web Feature And Coverage Service Performance: Towards Efficient Delivery Of Geospatial Data, Gregory Giuliani, Alain Dubois, Pierre Lacroix Dec 2013

Testing Ogc Web Feature And Coverage Service Performance: Towards Efficient Delivery Of Geospatial Data, Gregory Giuliani, Alain Dubois, Pierre Lacroix

Journal of Spatial Information Science

OGC Web Feature Service (WFS) and Web Coverage Service (WCS) specifications allow interoperable access to distributed geospatial data made available through spatial data infrastructures (SDIs). To ensure that a service is sufficiently responsive to fulfill users’ expectations and requirements performance of services must be measured and monitored to track latencies bottlenecks and errors that may negatively influence its over- all quality. Despite the importance of data retrieval and access little research has been published on this topic and mostly concentrates on the usability of services when integrating distributed data sources. Considering these issues this paper extends and validates the FOSS4G …


The Probabilistic Characterization Of Severe Rainstorm Events: Applications Of Threshold Analysis To Climate Change Impacts, Barry A. Palynchuk Phd Dec 2013

The Probabilistic Characterization Of Severe Rainstorm Events: Applications Of Threshold Analysis To Climate Change Impacts, Barry A. Palynchuk Phd

Barry A. Palynchuk PhD

A summary of PhD thesis, with emphasis upon storm event definition, and climate change impacts upon rainfall depth, duration, and intensity.


Environmental Analysis Of Goes-R Proving Ground Convection Initiation Forecasting Algorithms, Jason M. Apke Dec 2013

Environmental Analysis Of Goes-R Proving Ground Convection Initiation Forecasting Algorithms, Jason M. Apke

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The enhanced temporal and spatial resolution of the GOES-R series will allow for the use of cloud top cooling based convection initiation (CI) forecasting algorithms. Two such algorithms have been created on the current generation of GOES satellites: theUniversityofWisconsincloud top cooling algorithm (UWCTC) and the University of Alabama-Huntsville’s satellite convection analysis and tracking algorithm (SATCAST). Preliminary analysis of algorithm products has led to speculation over pre-convective environmental effects on algorithm performance, which this study aims to examine. CI indications are used with objective segmentation tools to identify and cluster radar objects over theGreat Plainsbased on reflectivity quantitative and spatial thresholds. …


The Progenitors Of The Compact Early-Type Galaxies At High Redshift, Christina C. Williams, Mauro Giavalisco, Paolo Cassata, Elena Tundo, Tommy Wiklind, Yicheng Guo, Bomee Lee, Guillermo Barro, Stijn Wuyts, Eric F. Bell, Christopher J. Conselice, Avishai Dekel, Sandra M. Faber, Henry C. Ferguson, Norman A. Grogin, Nimish Hathi, Kuang-Han Huang, Dalibor D. Kocevski, Anton M. Koekemoer, David C. Koo, Swara Ravindranath, Sarah Salimbeni Dec 2013

The Progenitors Of The Compact Early-Type Galaxies At High Redshift, Christina C. Williams, Mauro Giavalisco, Paolo Cassata, Elena Tundo, Tommy Wiklind, Yicheng Guo, Bomee Lee, Guillermo Barro, Stijn Wuyts, Eric F. Bell, Christopher J. Conselice, Avishai Dekel, Sandra M. Faber, Henry C. Ferguson, Norman A. Grogin, Nimish Hathi, Kuang-Han Huang, Dalibor D. Kocevski, Anton M. Koekemoer, David C. Koo, Swara Ravindranath, Sarah Salimbeni

Physics and Astronomy Faculty Publications

We use GOODS and CANDELS images to identify progenitors of massive (M > 1010 M ) compact early-type galaxies (ETGs) at z ~ 1.6. Because merging and accretion increase the size of the stellar component of galaxies, if the progenitors are among known star-forming galaxies, these must be compact themselves. We select candidate progenitors among compact Lyman-break galaxies at z ~ 3 on the basis of their mass, star-formation rate (SFR), and central stellar density, and we find that these account for a large fraction of, and possibly all, compact ETGs at z ~ 1.6. We find that …


When All Seems Lost: A Discussion On The Implications Of Using Medicine For Scientific Advances, Rebecca Monterusso Dec 2013

When All Seems Lost: A Discussion On The Implications Of Using Medicine For Scientific Advances, Rebecca Monterusso

Honors Theses

When All is Lost is a creative non-fiction piece following the lives of two fictional characters living during World War" and the Holocaust. It is meant to discuss the moral quandary when human experimentation is used for the purpose of scientific advancement. The two main characters lives' are depicted in a series of modified scenes that describe what happens to them throughout the war. Leo Weinstock is a Jewish man who is chosen for the high-altitude experiments at Dachau after he is imprisoned during Kristallnacht. Erich, on the other hand, is a young, successful Luftwaffe pilot defending his country. Both …


Shifting Environmental Controls On Ch4 Fluxes In A Sub-Boreal Peatland, Thomas G. Pypker, P. A. Moore, John A. Hribljan, Rodney Chimner Dec 2013

Shifting Environmental Controls On Ch4 Fluxes In A Sub-Boreal Peatland, Thomas G. Pypker, P. A. Moore, John A. Hribljan, Rodney Chimner

Michigan Tech Publications

We monitored CO2 and CH4 fluxes using eddy covariance from 19 May to 27 September 2011 in a poor fen located in northern Michigan. The objectives of this paper are to: (1) quantify the flux of CH4 from a sub-boreal peatland, and (2) determine which abiotic and biotic factors were the most correlated to the flux of CH4 over the measurement period. Net daily CH4 fluxes increased from 70 mg CH4 m−2 d−1 to 220 mg CH4 m−2 d−1 from mid May to mid July. After July, CH4 …


The Unexpectedly Bright Comet C/2012 F6 (Lemmon) Unveiled At Near-Infrared Wavelengths, Lucas Paganini, Michael Disanti, Michael Mumma, Geronimo Villanueva, Boncho Bonev, Jacqueline Keane, Erika Gibb, Hermann Boehnhardt, Karen Meech Dec 2013

The Unexpectedly Bright Comet C/2012 F6 (Lemmon) Unveiled At Near-Infrared Wavelengths, Lucas Paganini, Michael Disanti, Michael Mumma, Geronimo Villanueva, Boncho Bonev, Jacqueline Keane, Erika Gibb, Hermann Boehnhardt, Karen Meech

Physics Faculty Works

We acquired near-infrared spectra of the Oort cloud comet C/2012 F6 (Lemmon) at three different heliocentric distances (R h) during the comet's 2013 perihelion passage, providing a comprehensive measure of the outgassing behavior of parent volatiles and cosmogonic indicators. Our observations were performed pre-perihelion at R h = 1.2 AU with CRIRES (on 2013 February 2 and 4), and post-perihelion at R h = 0.75 AU with CSHELL (on March 31 and April 1) and R h = 1.74 AU with NIRSPEC (on June 20). We detected 10 volatile species (H2O, OH* prompt emission, C2H6, CH3OH, H2CO, HCN, CO, CH4, …


Determination Of The Top-Quark Pole Mass And Strong Coupling Constant From The T T-Bar Production Cross Section In Pp Collisions At Sqrt(S) = 7 Tev, Cms Collaboration, Vanessa Gaultney, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez Dec 2013

Determination Of The Top-Quark Pole Mass And Strong Coupling Constant From The T T-Bar Production Cross Section In Pp Collisions At Sqrt(S) = 7 Tev, Cms Collaboration, Vanessa Gaultney, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

The inclusive cross section for top-quark pair production measured by the CMS experiment in proton–proton collisions at a center-of-mass energy of 7 TeV is compared to the QCD prediction at next-to-next-to-leading order with various parton distribution functions to determine the top-quark pole mass, m[pole over t], or the strong coupling constant, α[subscript S]. With the parton distribution function set NNPDF2.3, a pole mass of 176.7[+3.8 over −3.4] GeV is obtained when constraining α[subscript S] at the scale of the Z boson mass, m[subscript Z], to the current world average. Alternatively, by constraining m[pole over t] to the latest average from …


Optically-Pumped Spin-Exchange Polarized Electron Source, Munir Pirbhai Dec 2013

Optically-Pumped Spin-Exchange Polarized Electron Source, Munir Pirbhai

Department of Physics and Astronomy: Dissertations, Theses, and Student Research

Polarized electron beams are an indispensable probe of spin-dependent phenomena in fields of atomic and molecular physics, magnetism and biophysics. While their uses have become widespread, the standard source based on negative electron affinity gallium arsenide (GaAs) remains technically complicated. This has hindered progress on many experiments involving spin-polarized electrons, especially those using target gas loads, which tend to adversely affect the performance of GaAs sources. A robust system based on an alternative way to make polarized electron beams has been devised in this study, which builds on previous work done in our lab. It involves spin-exchange collisions between free, …


Using Intelligent Prefetching To Reduce The Energy Consumption Of A Large-Scale Storage System, Brian Romoser, Ziliang Zong, Ribel Fares, Joal Wood, Rong Ge Dec 2013

Using Intelligent Prefetching To Reduce The Energy Consumption Of A Large-Scale Storage System, Brian Romoser, Ziliang Zong, Ribel Fares, Joal Wood, Rong Ge

Mathematics, Statistics and Computer Science Faculty Research and Publications

Many high performance large-scale storage systems will experience significant workload increases as their user base and content availability grow over time. The U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) center hosts one such system that has recently undergone a period of rapid growth as its user population grew nearly 400% in just about three years. When administrators of these massive storage systems face the challenge of meeting the demands of an ever increasing number of requests, the easiest solution is to integrate more advanced hardware to existing systems. However, additional investment in hardware may significantly increase the …


Stability And Entanglement In An Optomechanical System, Matthew Schumacher Dec 2013

Stability And Entanglement In An Optomechanical System, Matthew Schumacher

Theses

Optomechanical systems are currently of great interest as they lie at the boundary between quantum and classical mechanics, promising fundamental insights as well as new technologies. The practical operation of an optomechanical system requires that it satisfy the criteria of mechanical stability. Further, for quantum applications, it is important to characterize the degree of nonclassical correlation present between the mechanical and optical subsystems. In this study, we analyze the stability and entanglement in an optomechanical system where couplings linear as well as quadratic in the mechanical displacement are present simultaneously. Such systems can be realized experimentally. Our analysis of the …


Application Of Receiver Operating Characteristic (Roc) Curves For Explosives Detection Using Different Sampling And Detection Techniques, Mimy Young, Wen Fan, Anna Raeva, Jose Almirall Dec 2013

Application Of Receiver Operating Characteristic (Roc) Curves For Explosives Detection Using Different Sampling And Detection Techniques, Mimy Young, Wen Fan, Anna Raeva, Jose Almirall

Department of Chemistry and Biochemistry

Reported for the first time are receiver operating characteristic (ROC) curves constructed to describe the performance of a sorbent-coated disk, planar solid phase microextraction (PSPME) unit for non-contact sampling of a variety of volatiles. The PSPME is coupled to ion mobility spectrometers (IMSs) for the detection of volatile chemical markers associated with the presence of smokeless powders, model systems of explosives containing diphenylamine (DPA), 2,4-dinitrotoluene (2,4-DNT) and nitroglycerin (NG) as the target analytes. The performance of the PSPME-IMS was compared with the widely accepted solid-phase microextraction (SPME), coupled to a GC-MS. A set of optimized sampling conditions for different volume …


Redesign Of Johar: A Framework For Developing Accessible Applications, Oladapo Oyebode Dec 2013

Redesign Of Johar: A Framework For Developing Accessible Applications, Oladapo Oyebode

Electronic Thesis and Dissertation Repository

As the population of disabled people continues to grow, designing accessible applications is still a challenge, since most applications are incompatible with assistive technologies used by disabled people to interact with the computer. This accessibility issue is usually caused by the reluctance of software engineers or developers to include complete accessibility features in their applications, which in turn is often due to the extra cost and development effort required to dynamically adapt applications to a wide range of disabilities. Our aim to resolve accessibility issues led to the design and implementation of the "Johar" framework, which facilitates the development of …


The Unexpectedly Bright Comet C/2012 F6 (Lemmon) Unveiled At Near-Infrared Wavelengths, Lucas Paganini, Michael A. Disanti, Michael J. Mumma, Geronimo L. Villanueva, Boncho P. Bonev, Jacqueline V. Keane, Erika L. Gibb, Hermann Boehnhardt, Karen J. Meech Dec 2013

The Unexpectedly Bright Comet C/2012 F6 (Lemmon) Unveiled At Near-Infrared Wavelengths, Lucas Paganini, Michael A. Disanti, Michael J. Mumma, Geronimo L. Villanueva, Boncho P. Bonev, Jacqueline V. Keane, Erika L. Gibb, Hermann Boehnhardt, Karen J. Meech

Erika Gibb

We acquired near-infrared spectra of the Oort cloud comet C/2012 F6 (Lemmon) at three different heliocentric distances (R h) during the comet's 2013 perihelion passage, providing a comprehensive measure of the outgassing behavior of parent volatiles and cosmogonic indicators. Our observations were performed pre-perihelion at R h = 1.2 AU with CRIRES (on 2013 February 2 and 4), and post-perihelion at R h = 0.75 AU with CSHELL (on March 31 and April 1) and R h = 1.74 AU with NIRSPEC (on June 20). We detected 10 volatile species (H2O, OH* prompt emission, C2H6, CH3OH, H2CO, HCN, CO, CH4, …


The Upscattering Of Ultracold Neutrons From The Polymer (C6h12)N, Eduard I. Sharapov, Christopher L. Morris, Mark Makela, Andy Saunders, Evan R. Adamek, Leah J. Broussard, Chris B. Cude-Woods, Deion E. Fellers, Peter Geltenbort, Monika Hartl, Siraj I. Hasan, Kevin P. Hickerson, Gary E. Hogan, Anthony T. Holley, C. M. Lavelle, Chen-Yu Liu, Michael P. Mendenhall, Jose Ortiz, Robert W. Pattie, David G. Phillips, John Ramsey, Daniel J. Salvat, Susan J. Seestrom, Erik Shaw, Sky Sjue, Walter E. Sondheim, Brittany Vorndick, Zhehui Wang, Tanner L. Womack, Andrew R. Young, B. A. Zeck Dec 2013

The Upscattering Of Ultracold Neutrons From The Polymer (C6h12)N, Eduard I. Sharapov, Christopher L. Morris, Mark Makela, Andy Saunders, Evan R. Adamek, Leah J. Broussard, Chris B. Cude-Woods, Deion E. Fellers, Peter Geltenbort, Monika Hartl, Siraj I. Hasan, Kevin P. Hickerson, Gary E. Hogan, Anthony T. Holley, C. M. Lavelle, Chen-Yu Liu, Michael P. Mendenhall, Jose Ortiz, Robert W. Pattie, David G. Phillips, John Ramsey, Daniel J. Salvat, Susan J. Seestrom, Erik Shaw, Sky Sjue, Walter E. Sondheim, Brittany Vorndick, Zhehui Wang, Tanner L. Womack, Andrew R. Young, B. A. Zeck

Robert W. Pattie Jr.

It is generally accepted that the main cause of ultracold neutron (UCN) losses in storage traps is upscattering to the thermal energy range by hydrogen adsorbed on the surface of the trap walls. However, the data on which this conclusion is based are poor and contradictory. Here we report a measurement, performed at the Los Alamos National Laboratory UCN source, of the average energy of the flux of upscattered neutrons after the interaction of UCN with hydrogen bound in the semicrystalline polymer PMP (trade name TPX), [C6H12]n. Our analysis, performed with the mcnp code which applies …


Waste Management And Water Quality Issues In Coastal States Of Nigeria: The Ogun State Experience, Solomon Isiorho Dec 2013

Waste Management And Water Quality Issues In Coastal States Of Nigeria: The Ogun State Experience, Solomon Isiorho

S Isiorho

Waste dumping and inadequate waste management efforts are having adverse impact on the environment and humans in Nigerian coastal cities. Nine of the 36 states in Nigeria border the Atlantic Ocean. Twenty-five percent of the Nigerian population is found in the coastal states. These states, with the exception of Lagos, Ogun and Ondo, are more prone to petrochemical waste arising from petroleum exploration. Filed investigations, surveys and literature searches were conducted in order to accomplish the task of this research. Field studies included testing for dissolved oxygen, biological oxygen demand, nitrates, phosphates, total solids and pH.


Undergrduates Conference Attendance, A Win-Win Situation For Students And Their Home Institution, Solomon Isiorho Dec 2013

Undergrduates Conference Attendance, A Win-Win Situation For Students And Their Home Institution, Solomon Isiorho

S Isiorho

No abstract provided.


Upward Bound Program And Inquiry-Based Activities In Wetland Settings., Solomon Isiorho Dec 2013

Upward Bound Program And Inquiry-Based Activities In Wetland Settings., Solomon Isiorho

S Isiorho

No abstract provided.


Wetlands, Solomon Isiorho Dec 2013

Wetlands, Solomon Isiorho

S Isiorho

No abstract provided.


Water Quality Assessment Of A Mid-West City Water Distribution System, Solomon Isiorho, A Morse, N Flores Dec 2013

Water Quality Assessment Of A Mid-West City Water Distribution System, Solomon Isiorho, A Morse, N Flores

S Isiorho

No abstract provided.


When A Professor Becomes A Student Again!", Solomon Isiorho Dec 2013

When A Professor Becomes A Student Again!", Solomon Isiorho

S Isiorho

No abstract provided.