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2008

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Full-Text Articles in Physical Sciences and Mathematics

Ssrn As An Initial Revolution In Academic Knowledge Aggregation And Dissemination, David Bray, Sascha Vitzthum, Benn Konsynski Jan 2010

Ssrn As An Initial Revolution In Academic Knowledge Aggregation And Dissemination, David Bray, Sascha Vitzthum, Benn Konsynski

Sascha Vitzthum

Within this paper we consider our results of using the Social Science Research Network (SSRN) over a period of 18 months to distribute our working papers to the research community. Our experiences have been quite positive, with SSRN serving as a platform both to inform our colleagues about our research as well as inform us about related research (through email and telephoned conversations of colleagues who discovered our paper on SSRN). We then discuss potential future directions for SSRN to consider, and how SSRN might well represent an initial revolution in 21st century academic knowledge aggregation and dissemination. Our paper ...


The 4 X 4 Semantic Model: Exploiting Data, Functional, Non-Functional And Execution Semantics Across Business Process, Workflow, Partner Services And Middleware Services Tiers, Amit P. Sheth, Karthik Gomadam Dec 2008

The 4 X 4 Semantic Model: Exploiting Data, Functional, Non-Functional And Execution Semantics Across Business Process, Workflow, Partner Services And Middleware Services Tiers, Amit P. Sheth, Karthik Gomadam

Kno.e.sis Publications

Business processes in the global environment increasingly encompass multiple partners and complex, rapidly changing requirements. In this context it is critical that strategic business objectives align with and map accurately to systems that support flexible and dynamic business processes. To support the demanding requirements of global business processes, we propose a comprehensive, unifying 4 X 4 Semantic Model that uses Semantic Templates to link four tiers of implementation with four types of semantics. The four tiers are the Business Process Tier, the Workflow Enactment Tier, the Partner Services Tier, and the Middleware Services Tier. The four types of semantics are ...


Automatic Reaction To A Chemical Event Detected By A Low-Cost Wireless Chemical Sensing Network, Stephen Beirne, King Tong Lau, Brian Corcoran, Dermot Diamond Dec 2008

Automatic Reaction To A Chemical Event Detected By A Low-Cost Wireless Chemical Sensing Network, Stephen Beirne, King Tong Lau, Brian Corcoran, Dermot Diamond

Faculty of Science - Papers (Archive)

A test-scale wireless chemical sensor network (WCSN) has been deployed within a controlled Environmental Chamber (EC). The combined signals from the WCSN were used to initiate a controllable response to the detected chemical event. When a particular sensor response pattern was obtained, a purging cycle was initiated. Sensor data were continuously checked against user-defined action limits, to determine if a chemical event had occurred. An acidic contaminant was used to demonstrate the response of the sensor network. Once the acid plume was simultaneously detected by a number of wireless chemical sensor nodes, an automatic response action, which was the purging ...


Terahertz Response Of Microfluidic-Jetted Fabricated 3d Flexible Metamaterials, Yew Li Hor Dec 2008

Terahertz Response Of Microfluidic-Jetted Fabricated 3d Flexible Metamaterials, Yew Li Hor

Dissertations

Conventional materials exhibit some restrictions on their electromagnetic properties. Especially in terahertz region, for example, materials that exhibit magnetic response are far less common in nature than materials that exhibit electric response. However, materials can be designed, namely artificial man-made metamaterials that exhibit electromagnetic properties that are not found in natural materials by adjusting, for example, the dielectric, magnetic or structural parameters of the constituent elements.

This dissertation demonstrates the use of new fabrication techniques to construct metamaterials in THz range via a material deposition system. The metamaterials are fabricated by stacking alternative layers with conventional designs such as single ...


Synchrotron Radiation-Based Characterization Of Gan- Based Mqw Structures And Strongly Correlated Materials, Sean M. O'Malley Dec 2008

Synchrotron Radiation-Based Characterization Of Gan- Based Mqw Structures And Strongly Correlated Materials, Sean M. O'Malley

Dissertations

The following dissertation applies synchrotron radiation-based characterization techniques to the fields of gallium nitrides, multiferroic manganites, and self-assembled nano-domain oxide films. These material systems were chosen due to their unusual properties and potential device applications, which have made them very attractive to the scientific community.

Synchrotron-based High Resolution X-ray Diffraction (HRXRD) was used to characterize the structural properties of GaN-based multiple quantum well (MQW) structures grown on trapezoidal shaped GaN ridges. Results where interpreted within the framework of vapor-phase diffusion and surface-migration effects during the metalorganic vapor phase epitaxial growth. The relatively short diffusion length of group- III precursors and ...


Collaborative Learning Utilizing A Domain-Based Shared Data Repository To Enhance Learning Outcomes, David J. Lubliner Dec 2008

Collaborative Learning Utilizing A Domain-Based Shared Data Repository To Enhance Learning Outcomes, David J. Lubliner

Dissertations

A number of learning paradigms have postulated that knowledge formation is a dynamic process where learners actively construct a representation of concepts integrating information from multiple sources. Current teaching strategies utilize a compartmentalized approach where individual courses contain a small subset of the knowledge required for a discipline. The intent of this research is to provide a framework to integrate the components of a discipline into a cohesive whole and accelerate the integration of concepts enhancing the learning process. The components utilized to accomplish these goals include two new knowledge integration models; a Knowledge Weighting Model (KWM) and the Aggregate-Integrate-Master ...


Loss Of Synchrony In An Inhibitory Network Of Type-I Oscillators, Myongkeun Oh Dec 2008

Loss Of Synchrony In An Inhibitory Network Of Type-I Oscillators, Myongkeun Oh

Dissertations

Synchronization of excitable cells coupled by reciprocal inhibition is a topic of significant interest due to the important role that inhibitory synaptic interaction plays in the generation and regulation of coherent rhythmic activity in a variety of neural systems. While recent work revealed the synchronizing influence of inhibitory coupling on the dynamics of many networks, it is known that strong coupling can destabilize phase-locked firing. Here we examine the loss of synchrony caused by an increase in inhibitory coupling in networks of type-I Morris-Lecar model oscillators, which is characterized by a period-doubling cascade and leads to mode-locked states with alternation ...


Detecting Topological Features Of Chaotic Fluid Flow, Nicholas T. Ouellette, Jerry P. Gollub Dec 2008

Detecting Topological Features Of Chaotic Fluid Flow, Nicholas T. Ouellette, Jerry P. Gollub

Department of Physics Papers

No abstract provided.


Voting In Group Support Systems : Theory, Implementation, And Results From An Exploratory Study, Kung-E Cheng Dec 2008

Voting In Group Support Systems : Theory, Implementation, And Results From An Exploratory Study, Kung-E Cheng

Dissertations

Group decision making is essential in organizations. Group Support Systems (GSS) can aide groups in making decisions by providing tools and process support. GSS is especially useful for geographically or temporally distributed groups. Researchers of GSS have pointed out that convergence processes are hard to accomplish in GSS. Voting tools in GSS can be a valuable asset in alleviating the difficulty of convergence processes because voting is a concise communication of individual preferences with a well defined procedure that is accepted by group members. In addition, voting results can serve as a group memory of the convergence processes. Field observations ...


Nevada Interagency Volunteer Program: Helping Hands Across Public Lands – Phase Ii: Quarterly Progress Report, Period Covering October 1 – December 31, 2008, Margaret N. Rees Dec 2008

Nevada Interagency Volunteer Program: Helping Hands Across Public Lands – Phase Ii: Quarterly Progress Report, Period Covering October 1 – December 31, 2008, Margaret N. Rees

Get Outdoors Nevada

  • The number of records in the volunteer database increased 8% over last quarter. The database now contains 6,431 records.
  • Website activity increased, recording an average of 56,013 hits per month, an increase of 6% from last quarter, with an average of 5,211 pages viewed per month.
  • Volunteer fall training has been completed.
  • Three National Public Land Day and National Family Events have been completed.
  • Two hundred and five people attended the Volunteer Recognition Event.


Lake Mead National Recreation Area Sensitive Wildlife Species Monitoring And Analysis: Quarterly Progress Report, Period Ending December 31, 2008, Margaret N. Rees Dec 2008

Lake Mead National Recreation Area Sensitive Wildlife Species Monitoring And Analysis: Quarterly Progress Report, Period Ending December 31, 2008, Margaret N. Rees

Wildlife Monitoring

Project 1. Relict Leopard Frog Monitoring, Management, and Research

  • All milestones and deliverables associated with the MSHCP project are on schedule
  • Completion of 2008 monitoring survey efforts
  • Coordination is ongoing to identify potential translocation sites, including assisting efforts to identify a potential site in the western Grand Canyon
  • RLFCT meeting hosted and minutes of meeting drafted
  • Annual report provided to RLFCT, final draft in review
  • Sampling for the amphibian chytrid fungus conducted at many sites

Project 2. Bald Eagle Winter Monitoring and Evaluation

  • All MSHCP milestones and deliverables are on schedule
  • Planning and coordination of the 2009 Eagle Count conducted ...


Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Report, Period Ending December 31, 2008, Margaret N. Rees Dec 2008

Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Report, Period Ending December 31, 2008, Margaret N. Rees

Limnological Studies

Project 1: Technical input has been provided at four advisory team meetings attended this quarter.

Project 2: A formal report titled, Surface Water Monitoring for Indicator Bacteria in High-use Sites of the Lake Mead National Recreation Area, has been prepared; an accompanying poster presentation for the Lake Mead Science Symposium is in preparation.

Project 3: A draft document titled, “Interagency Monitoring Action Plan (I-MAP): Quagga Mussels in Lakes Mead and Mohave” has been presented to an interagency core group to review and input. Six oral presentations related to quagga mussels are in preparation by this group for the Lake Mead ...


Masthead Dec 2008

Masthead

Journal of Digital Forensics, Security and Law

No abstract provided.


Thermochemistry And Bond Energies Of Nitro -Alkanes, -Alkenes, -Carbonyls And Corresponding Nitrites, Surawee Snitsiriwat Dec 2008

Thermochemistry And Bond Energies Of Nitro -Alkanes, -Alkenes, -Carbonyls And Corresponding Nitrites, Surawee Snitsiriwat

Theses

Density functional and ab initio theory based calculations were performed on a series of nitro -alkanes, -alkenes, carbonyl and corresponding nitrites representing large-scale primary, secondary and tertiary nitro compounds and their radicals resulting from the loss of skeletal hydrogen atoms. Geometries, vibration frequencies and thermochemical properties, ΔfH°298, S °(T) and C°p(T) (10K T 5 5000K) are calculated at the individual B3LYP/6-31G(d,p), B3LYP /6-31+G(2d,2p) and composite CBS-QB3 levels. Potential energy barriers for the internal rotations have been computed at the B3LYP/6-31G(d, p) level of theory and the lower barrier contributions ...


Back Matter Dec 2008

Back Matter

Journal of Digital Forensics, Security and Law

No abstract provided.


Road-Based Proactive Routing Protocols For Vehicular Networks, Neeraj Mahadevrao Rajgure Dec 2008

Road-Based Proactive Routing Protocols For Vehicular Networks, Neeraj Mahadevrao Rajgure

Theses

Vehicular networks are formed by vehicles communicating in an ad hoc manner or through cellular and IEEE 802.11 base stations. Routing in vehicular networks is challenging due to highly dynamic network topologies. Previous research done at the UbiNetS lab at NJIT has proposed the idea of Road-Based using Vehicular Traffic information (RBVT) routing. In RBVT, routes are sequences of road intersections, and geographical forwarding is used for sending packets between the intersections.

This thesis proposes two proactive RBVT protocols (RBVT-P and RBVT-PS) for city-based Vehicular Ad hoc NETworks (VANETs). RBVT-P is a completely distributed protocol that unicasts connectivity packets ...


Rna Secondary Structure Detection Programs With An Emphasis On Covariance Models, Justin Slotman Dec 2008

Rna Secondary Structure Detection Programs With An Emphasis On Covariance Models, Justin Slotman

Theses

RNA secondary structure prediction requires a different approach from traditional alignment methods. Functional RNAs often have their secondary structure better conserved than their primary structure. Covariance models, probabilistic models that utilize stochastic-context-free grammars, are one approach. CMs allow for homology to be detected where purely sequence-based methods would fail. A background on CMs is given, as well as a background of the major classes of non-coding RNAs (ncRNAs). Comparisons are made between some CM-using tools (the Infernal suite and CMfinder) and some other RNA secondary structure tools (CARNAC, miRNAminer, Pfold, Mfold) as well as between Infernal and the primary alignment ...


A Martingale Test For Alpha, Dean P. Foster, Robert A. Stine, H. Peyton Young Dec 2008

A Martingale Test For Alpha, Dean P. Foster, Robert A. Stine, H. Peyton Young

Statistics Papers

We present a new method for testing whether a fund manager’s track record allows us to infer that he is able to beat the market with high probability or is just plain lucky. The test is based on the martingale maximal inequality. Unlike other standard approaches the test is robust to the assumed distribution of returns while retaining substantial statistical power. The method is illustrated using stock market data from 1926‐2007.


Front Matter Dec 2008

Front Matter

Journal of Digital Forensics, Security and Law

No abstract provided.


Sustainable Site Remediation : A Life Cycle Assessment Approach, Harnoor Dhaliwal Dec 2008

Sustainable Site Remediation : A Life Cycle Assessment Approach, Harnoor Dhaliwal

Theses

Remediation of contaminated areas is often a resource-intensive activity that itself can create environmental burdens. Life cycle assessment (LCA) was used as a tool to examine the environmental impacts associated with remediation activities. A hypothetical contaminated site with five remediation alternatives was developed for this analysis. The results of Life cycle Impact Assessment (LCIA) indicated that greater site activity in terms of transportation, material and equipment use translated into higher environmental impacts.

A sensitivity analysis was performed to evaluate the environmental impacts further in different time horizons. The results showed that choice of time horizon can have a significant effect ...


Quad General Tree Drawing Algorithm And General Trees Characterization: Towards An Environment For The Experimental Study On General Tree Drawing Algorithms, Chu Yao Dec 2008

Quad General Tree Drawing Algorithm And General Trees Characterization: Towards An Environment For The Experimental Study On General Tree Drawing Algorithms, Chu Yao

Theses and Dissertations

Information visualization produces (interactive) visual representations of abstract data to reinforce human cognition and perception; thus enabling the viewer to gain knowledge about the internal structure of the data and causal relationships in it. The visualization of information hierarchies is concerned with the presentation of abstract hierarchical information about relationships between various entities. It has many applications in diverse domains such as software engineering, information systems, biology, and chemistry. Information hierarchies are typically modeled by an abstract tree, where vertices are entities and edges represent relationships between entities. The aim of visualizing tree drawings is to automatically produce drawings of ...


A Note On The Sub-Optimality Of Rank Ordering Of Objects On The Basis Of The Leading Principal Component Factor Scores, Sudhanshu K. Mishra Dec 2008

A Note On The Sub-Optimality Of Rank Ordering Of Objects On The Basis Of The Leading Principal Component Factor Scores, Sudhanshu K. Mishra

Sudhanshu K Mishra

This paper demonstrates that if we intend to optimally rank order n objects (candidates) each of which has m rank-ordered attributes or rank scores have been awarded by m evaluators, then the overall ordinal ranking of objects by the conventional principal component based factor scores turns out to be suboptimal. Three numerical examples have been provided to show that principal component based rankings do not necessarily maximize the sum of squared correlation coefficients between the individual m rank scores arrays, X(n,m), and overall rank scores array, Z(n).


Casimir Effect For Massless Fermions In One Dimension: A Force-Operator Approach, Dina Zhabinskaya, Jesse M. Kinder, Eugene J. Mele Dec 2008

Casimir Effect For Massless Fermions In One Dimension: A Force-Operator Approach, Dina Zhabinskaya, Jesse M. Kinder, Eugene J. Mele

Department of Physics Papers

We calculate the Casimir interaction between two short-range scatterers embedded in a background of one-dimensional massless Dirac fermions using a force-operator approach. We obtain the force between two finite-width square barriers and take the limit of zero width and infinite potential strength to study the Casimir force mediated by the fermions. For the case of identical scatterers, we recover the conventional attractive one-dimensional Casimir force. For the general problem with inequivalent scatterers, we find that the magnitude and sign of this force depend on the relative spinor polarizations of the two scattering potentials, which can be tuned to give an ...


Step-Wise Changes In Glacier Flow Speed Coincide With Calving And Glacial Earthquakes At Helheim Glacier, Greenland, M. Nettles, T. B. Larsen, P. Elósegui, Gordon S. Hamilton, Leigh A. Stearns, A. P. Ahlstrom, J. L. Davis, M. L. Andersen, J. De Juan, S. A. Khan, L. Stensing, G. Ekstrom, R. Forsberg Dec 2008

Step-Wise Changes In Glacier Flow Speed Coincide With Calving And Glacial Earthquakes At Helheim Glacier, Greenland, M. Nettles, T. B. Larsen, P. Elósegui, Gordon S. Hamilton, Leigh A. Stearns, A. P. Ahlstrom, J. L. Davis, M. L. Andersen, J. De Juan, S. A. Khan, L. Stensing, G. Ekstrom, R. Forsberg

Earth Science Faculty Scholarship

Geodetic observations show several large, sudden increases in flow speed at Helheim Glacier, one of Greenland's largest outlet glaciers, during summer, 2007. These step-like accelerations, detected along the length of the glacier, coincide with teleseismically detected glacial earthquakes and major iceberg calving events. No coseismic offset in the position of the glacier surface is observed; instead, modest tsunamis associated with the glacial earthquakes implicate glacier calving in the seismogenic process. Our results link changes in glacier velocity directly to calving-front behavior at Greenland's largest outlet glaciers, on timescales as short as minutes to hours, and clarify the mechanism ...


Topological Structures In The Equities Market Network, Gregory Leibon, Scott Pauls, Daniel Rockmore, Robert Savell Dec 2008

Topological Structures In The Equities Market Network, Gregory Leibon, Scott Pauls, Daniel Rockmore, Robert Savell

Open Dartmouth: Faculty Open Access Articles

We present a new method for articulating scale-dependent topological descriptions of the network structure inherent in many complex systems. The technique is based on “partition decoupled null models,” a new class of null models that incorporate the interaction of clustered partitions into a random model and generalize the Gaussian ensemble. As an application, we analyze a correlation matrix derived from 4 years of close prices of equities in the New York Stock Exchange (NYSE) and National Association of Securities Dealers Automated Quotation (NASDAQ). In this example, we expose (i) a natural structure composed of 2 interacting partitions of the market ...


Sub-Micron Parallel Laser Direct-Write, Christina Othon, Arnoldo Laracuente, H Ladoucuer, Bradley Ringeisen Dec 2008

Sub-Micron Parallel Laser Direct-Write, Christina Othon, Arnoldo Laracuente, H Ladoucuer, Bradley Ringeisen

Christina M Othon

We have developed a modified laser induced forward transfer (LIFT) technique which allows for the parallel deposition of hundreds of sub-micron features. The approach utilizes a self-assembled monolayer of monodisperse polystyrene microspheres as the focusing element. A monolayer of close-packed microspheres is formed on top of an ultra-thin quartz support (25 m thick), and a metallic thin film is then deposited on the underside of the quartz. This approach is different from previous parallel microsphere-assisted LIFT experiments that required the deposition of metal directly onto the surface of the periodic microsphere structure. For this study, an 800 nm, 130 fs ...


Analysis Of Adverse Events In Drug Safety: A Multivariate Approach Using Stratified Quasi-Least Squares, Hanjoo Kim, Justine Shults, Scott Patterson, Robert Goldberg-Alberts Dec 2008

Analysis Of Adverse Events In Drug Safety: A Multivariate Approach Using Stratified Quasi-Least Squares, Hanjoo Kim, Justine Shults, Scott Patterson, Robert Goldberg-Alberts

UPenn Biostatistics Working Papers

Safety assessment in drug development involves numerous statistical challenges, and yet statistical methodologies and their applications to safety data have not been fully developed, despite a recent increase of interest in this area. In practice, a conventional univariate approach for analysis of safety data involves application of the Fisher's exact test to compare the proportion of subjects who experience adverse events (AEs) between treatment groups; This approach ignores several common features of safety data, including the presence of multiple endpoints, longitudinal follow-up, and a possible relationship between the AEs within body systems. In this article, we propose various regression ...


Synthesis Analysis Of Regression Models With A Continuous Outcome, Andrew Zhou, Nan Hu, Guizhou Hu, Martin Root Dec 2008

Synthesis Analysis Of Regression Models With A Continuous Outcome, Andrew Zhou, Nan Hu, Guizhou Hu, Martin Root

UW Biostatistics Working Paper Series

Synthesis Analysis of Regression Models with a Continuous Outcome Xiao-Hua Zhou 1,2, Nan Hu 2, Guizhou Hu3, and Martin Root3 1 HSR&D Center of Excellence, VA Puget Sound Health Care System, Seattle, WA 98101. 2 Department of Biostatistics, University of Washington, Seattle, WA 98195. 3 BioSignia, Inc., 1822 East NC Highway 54, Suite 350, Durham, NC 27713 To estimate the multivariate regression model from multiple individual studies, it would be challenging to obtain results if the input from individual studies only provide univariate or incomplete multivariate regression information. Samsa et al [1] proposed a simple method to combine ...


Final Report: Task 22 — Extreme Ground Motion Studies, John G. Anderson, James N. Brune, Jaak J.K. Daemen, Matthew Purvance Dec 2008

Final Report: Task 22 — Extreme Ground Motion Studies, John G. Anderson, James N. Brune, Jaak J.K. Daemen, Matthew Purvance

Publications (YM)

TASK 22 consisted of two separate investigations into extreme ground motions due to seismic events, Subtask 1 and Subtask 2. Subtask 1 included field studies of geological formations that should put an upper bound on extreme ground motions that have happened at the site of the formations. The locations are critically selected to provide the most effective constraints possible on the validity of the probabilistic seismic hazard analysis for Yucca Mountain. Subtask 2 surveyed recorded ground motions from around the world, with the aim to draw general conclusions from these as to the conditions where extreme ground motions are observed ...


Structure And Dynamics Of Metalloproteins In Live Cells, Jeremy D. Cook, James E. Penner-Hahn, Timothy L. Stemmler Dec 2008

Structure And Dynamics Of Metalloproteins In Live Cells, Jeremy D. Cook, James E. Penner-Hahn, Timothy L. Stemmler

Biochemistry and Molecular Biology Faculty Publications

X-ray absorption spectroscopy (XAS) has emerged as one of the premier tools for investigating the structure and dynamic properties of metals in cells and in metal containing biomolecules. Utilizing the high flux and broad energy range of X-rays supplied by synchrotron light sources, one can selectively excite core electronic transitions in each metal. Spectroscopic signals from these electronic transitions can be used to dissect the chemical architecture of metals in cells, in cellular components and in biomolecules at varying degrees of structural resolution. With the development of ever-brighter X-ray sources, X-ray methods have grown into applications that can be utilized ...