Physical Sciences and Mathematics Commons^™

Concept Mapping As A Tool For Enhancing Self-Paced Learning In A Distance Scenario, John Allen Richbourg

Walden Dissertations and Doctoral Studies

Researchers have determined that concept maps serve as effective tools in the traditional science classroom. The purpose of this experimental study was to investigate concept mapping as a tool for student knowledge acquisition in 10th grade science for students in distance learning situations. Research questions were designed to investigate the influence of concept mapping on rate and quality of student knowledge acquisition and retention. This study was a pretest-posttest 2-group comparison study, constructivist in nature and based on the theory of cognitive learning. Participants included 36 students in the 10th grade at an inner-city school in the United States. Control …

The Relationship Between Information Technology And Organizational Effectiveness As Perceived By Health Care Providers, Christian Chikwem Ukaga

Walden Dissertations and Doctoral Studies

The U.S. Congress has made health information technology a central component of the national quest to improve health care delivery. The problem addressed in this study was the uncertainty among healthcare providers regarding the benefits of health care information technology adoption relative to healthcare delivery processes and outcomes. The purpose of the study was to understand the effectiveness of information technology as perceived by healthcare providers. The research questions were designed to investigate the relationship between health information technology and organizational effectiveness, exchange of information, organizational process, organizational productivity, and direct personal care. Sociotechnical systems theory and Donabedian's framework for …

Information Operations Under International Law: A Delphi Study Into The Legal Standing Of Cyber Warfare, Kenneth Gualtier

Walden Dissertations and Doctoral Studies

The ever-growing interconnectivity of industry and infrastructure through cyberspace has increased their vulnerability to cyber attack. The lack of any formal codification of cyber warfare has led to the development of contradictory state practices and disagreement as to the legal standing of cyber warfare, resulting in an increased risk of damage to property and loss of life. Using the just war theory as a foundation, the research questions asked at the point at which cyber attacks meet the definition of use of force or armed attack under international law and what impediments currently exist in the development of legal limitations …

The Value Of Diagnostic Software And Doctors' Decision Making, Babatunde Ayodele Alaofin

Walden Dissertations and Doctoral Studies

The prevalence of medical misdiagnosis has remained high despite the adoption of diagnostic software. This ongoing controversy about the role of technology in mitigating the problem of misdiagnosis centers on the question of whether diagnostic software does reduce the incidence of misdiagnosis if properly relied upon by physicians. The purpose of this quantitative, cross-sectional study based on planned behavior theory was to measure doctors' opinions of diagnostic technology's medical utility. Recruitment e-mails were sent to 3,100 AMA-accredited physicians through their database that yielded a sample of 99 physicians for the study. One-sample t tests and, where appropriate because of non-normal …

Impact Of Eu Medical Device Directive On Medical Device Software, Guy Foe Owono

Walden Dissertations and Doctoral Studies

Directive 2007/47/EC of the European Parliament amending Medical Device Directive (MDD) provides medical device manufacturers with a compliance framework. However, the effects of the amendments to the MDD on competition in the U.S. medical device software industry are unknown. This study examined the impact of this directive on the competitiveness of U.S. medical device software companies, the safety and efficacy of medical device software, employee training, and recruitment. The conceptual framework for this study included 3 dimensions of medical device regulations: safety, performance, and reliability. The overall research design was a concurrent mixed method study using both quantitative and qualitative …

Transformational Leadership And Safe Driving Performance In The U.S. Electric Utility Industry, Mackington Joseph

Walden Dissertations and Doctoral Studies

Transformational leadership (TL) has been found popular in many industries in the United States and abroad for the perceived transformational leaders' effectiveness in improving occupational safety. There is a lack of empirical evidence to confirm these claims for safe occupational driving. This phenomenological study attempted to fill this knowledge gap in the electric utility industry where employees must drive in all weather conditions to restore power to customers. The conceptual framework for the study was based on leadership and motivation theories of Burns and Maslow. The research questions explored the influence of (a) TL on safe driving performance improvement in …

Intra- And Inter-Seasonal Variability Of Supra-Glacial 1 Streams And Lakes Over The West Greenland Ice Sheet 2 From High-Resolution Satellite Optical Data, Michael Gregory Brown

Dissertations and Theses

The Greenland ice sheet (GrIS) is one of the largest glacial ice masses on Earth, second only to the Antarctic ice sheet. The surface hydrology of the GrIS plays a crucial role on the surface energy and mass balance budgets of the ice sheet as a whole. Surface water, known as supra-glacial water, is seasonally found in the ablation zone and feeds the en-glacial and sub-glacial hydrological environments of the ice sheet. The spatial distribution of surface streams is poorly understood and their temporal variability is (to our knowledge) unknown. One of the reasons for the lack of knowledge on …

Risk Management In Data Protection, Fred H. Cate, Christopher Kuner, Christopher Millard, Dan Jerker B. Svantesson, Orla Lynskey

Articles by Maurer Faculty

No abstract provided.

Phosphorus Retention In A Lowland Neotropical Stream Following An Eight-Year Enrichment Experiment, Gaston E. Small, Marcelo Ardón, John H. Duff, Alan P. Jackman, Alonso Ramírez, Frank J. Triska, Catherine M. Pringle

United States Geological Survey: Staff Publications

Human alteration of the global P cycle has led to widespread P loading in freshwater ecosystems. Much research has been devoted to the capacity of wetlands and lakes to serve as long-term sinks for P inputs from the watershed, but we know much less about the potential of headwater streams to serve in this role. We assessed storage and retention of P in biotic and abiotic compartments after an 8-y experimental P addition to a 1st-order stream in a Neotropical wet forest. Sediment P extractions indicated that nearly all P storage was in the form of Fe- and Al-bound P …

Decadal Re-Evaluation Of Contaminant Exposure And Productivity Of Ospreys (Pandion Haliaetus) Nesting In Chesapeake Bay Regions Of Concern, Rebecca S. Lazarus, Barnett A. Rattner, Peter C. Mcgowan, Robert C. Hale, Sandra L. Schultz, Natalie K. Karouna-Renier, Mary Ann Ottinger

United States Geological Survey: Staff Publications

The last large-scale ecotoxicological study of ospreys (Pandion haliaetus) in Chesapeake Bay was conducted in 2000-2001 and focused on U.S. EPA-designated Regions of Concern (ROCs; Baltimore Harbor/ Patapsco, Anacostia/middle Potomac, and Elizabeth Rivers). In 2011-2012, ROCs were re-evaluated to determine spatial and temporal trends in productivity and contaminants. Concentrations of p,p'-DDE were low in eggs and below the threshold associated with eggshell thinning. Eggs from the Anacostia/ middle Potomac Rivers had lower total PCB concentrations in 2011 than in 2000; however, concentrations remained unchanged in Baltimore Harbor. Polybrominated diphenyl ether flame retardants declined by 40%, and five alternative …

Sophie Germain Primes And Involutions Of Znx, Karenna Genzlinger, Keir H. Lockridge

Math Faculty Publications

In the paper “What is special about the divisors of 24?”, Sunil Chebolu proved an interesting result about the multiplication tables of Zn from several different number theoretic points of view: all of the 1s in the multiplication table for Zn are located on the main diagonal if and only if n is a divisor of 24. Put another way, this theorem characterizes the positive integers n with the property that the proportion of 1s on the diagonal is precisely 1. The present work is concerned with finding the positive integers n for which there is a given fixed proportion …

2015 Academic Program Review School Of Natural Resources University Of Nebraska–Lincoln

School of Natural Resources: Documents and Reviews

No abstract provided.

Improvements On Instrumentation To Explore The Multidimensionality Of Luminescence Spectroscopy, Anthony Moore

Electronic Theses and Dissertations

This dissertation presents experimental and instrumentation developments that take full advantage of the multidimensional nature of line narrowing spectroscopy at liquid nitrogen (77 K) and liquid helium (4.2 K) temperatures. The inconvenience of sample freezing procedures is eliminated with the aid of cryogenic fiber optic probes. Rapid collection of multidimensional data formats such as wavelength time matrices, excitation emission matrices, time-resolved excitation emission matrices and time resolved excitation emission cubes is made possible with the combination of a pulsed tunable dye laser, a spectrograph and an intensifier-charged coupled device. These data formats provide unique opportunities for processing vibrational luminescence data …

Optical Fibers For Space-Division Multiplexed Transmission And Networking, Cen Xia

Electronic Theses and Dissertations

Single-mode fiber transmission can no longer satisfy exponentially growing capacity demand. Space-division multiplexing (SDM) appears to be the only way able to dramatically improve the transmission capacity, for which, novel optical fiber is one of the key technologies. Such fibers must possess the following characteristics: 1) high mode density per cross-sectional area and 2) low crosstalk or low modal differential group delay (DMGD) to reduce complexity of digital signal processing. In this dissertation, we explore the design and characterization of three kinds of fibers for SDM: few-mode fiber (FMF), few-mode multi-core fiber (FM-MCF) and coupled multi-core fiber (CMCF) as well …

Aggregation Of Squaraine Dye Derivatives In Solid State Spin-Coated Thin Films, Mohammed Daoudi

Electronic Theses and Dissertations

Squaraine dyes have been the subject of intensive studies due their unusual electronic properties that make them good candidates for a wide range of applications in various technological fields. They are particularly promising in nonlinear optics, bioimaging for labeling and sensing of biomolecules, as sensitizers for solar energy harvesting in solar cells and organic photovoltaics, two-photon absorbing materials, near-infrared (NIR) emitting fluorescent probes, second harmonic generation organic dyes, and sensitizers for photodynamic therapy among others. In this dissertation, the aggregation behaviors and features of several squaraine dye derivatives in solid state thin films were studied and reported. In the first …

Modeling Crowd Mobility And Communication In Wireless Networks, Gurkan Solmaz

Electronic Theses and Dissertations

This dissertation presents contributions to the fields of mobility modeling, wireless sensor networks (WSNs) with mobile sinks, and opportunistic communication in theme parks. The two main directions of our contributions are human mobility models and strategies for the mobile sink positioning and communication in wireless networks. The first direction of the dissertation is related to human mobility modeling. Modeling the movement of human subjects is important to improve the performance of wireless networks with human participants and the validation of such networks through simulations. The movements in areas such as theme parks follow specific patterns that are not taken into …

Development Of An Automated Method For Identification Of Wet And Dry Channel Segments Using Lidar Data And Fuzzy Logic Cluster Analysis, Chris Rowney

Electronic Theses and Dissertations

Research into the use of LiDAR data for purposes other than simple topographic elevation determination, such as urban land cover classification and the identification of forest biomass, has become prominent in recent years. In many cases, alternative analysis methodologies conducted using airborne LiDAR data are possible because the raw data collected during a survey can include information other than the classically used elevation and coordinate points, the X, Y, and Z of the plane. In particular, intensity return values for each point in a LiDAR grid have been found to provide a useful data set for wet and dry channel …

Broadband Coherent Perfect Absorption In One-Dimensional Optical Systems, Massimo Maximilian Villinger

Electronic Theses and Dissertations

Absorption plays a critical role in a variety of optical applications – sometimes it is desirable to minimize it as in optical fibers and waveguides, or to enhance it as in solar cells and photodetectors. We describe here a new optical scheme that controllably produces high optical absorption over a broad wavelength range (hundreds of nm) in systems that have low intrinsic absorption over the same range. This effect, 'coherent perfect absorption' or CPA, arises from a subtle interplay between interference and absorption of two beams incident on a weakly absorbing medium. In the first part of this study, we …

Virtual Polytopes, G. Yu Panina, I. Streinu

Computer Science: Faculty Publications

Originating in diverse branches of mathematics, from polytope algebra and toric varieties to the theory of stressed graphs, virtual polytopes represent a natural algebraic generalization of convex polytopes. Introduced as elements of the Grothendieck group associated to the semigroup of convex polytopes, they admit a variety of geometrizations. The present survey connects the theory of virtual polytopes with other geometrical subjects, describes a series of geometrizations together with relations between them, and gives a selection of applications.

Resistive Pulse Study Of Vesicles And Liposomes, Yuqing Lin

Electronic Theses and Dissertations

In this work, the properties of the liposomes, the artificially created vesicles by various methods, are explored by a resistive pulse method using micropipettes. The fact that vesicles are fundamental in the wide range of functionalities they fulfill as organelles strengthen the desire of understanding the properties of them. The motivation of this work comes from the significant roles that liposomes play in the development of targeted drug delivery systems. Among other significant variables, the size of liposomes is found to be one of the dominating parameters in liposome based drug delivery, and the correlation between liposome size and delivery …

Synchrotron Based Infrared Microspectroscopy Of Carbonaceous Chondrites., Mehmet Yesiltas

Electronic Theses and Dissertations

Relationships between organic molecules and inorganic minerals are investigated in five carbonaceous chondrites, Northwest Africa 852 (CR2), Tagish Lake (C2-ungroupped), Orgueil (CI1), Sutter's Mill (CM), and Murchison (CM2), with micron spatial resolution using synchrotron-based imaging micro-FTIR spectroscopy. Correlations based on absorption strength for various constituents are determined using statistical correlation analysis. Silicate band is found to be positively correlated with stretching modes of aliphatic hydrocarbons in NWA 852 and Tagish Lake. The former is highly correlated with the hydration band in all meteorites. Negative correlation is observed between water+organics and carbonate bands in all meteorites. Two dimensional infrared maps for …

The Numerical Solution Of The Exterior Impedance (Robin) Problem For The Helmholtz’S Equation Via Modified Galerkin Method: Superllipsoid, Hy Dinh

Mathematics Theses

This thesis focuses on finding the solution for the exterior Robin Problem for the Helmholtz Equation and therefore, determines how a convergent smooth surface depending on its outer shape, in this case the superellipsoid, responds to different outer waves. The primary purpose is to calculate the possibility of a certain object, acquiring sufficient conditions, to either submerge under respectively high water pressure or maintain in outer space; if applicable, this approach can be used for a new efficient design of a portion of a submarine or part of a space craft, the second of more interest to NASA, one of …

Designing Core/Alloy Nanoparticles By Manipulation Of Interfacial Oxidation And Atomic Diffusion, Rahiem Davon Slaton

Dissertations - ALL

Alloying presents a unique opportunity to combine the chemical and physical properties of two or more metals into one material. This phenomenon can also be used for multi-metallic nanoparticles (NPs), where in conjunction with the size effects induced by quantum confinement, new properties or phase behavior can emerge. The properties of nanoalloys are highly dependent on their composition and morphology, which are contingent upon the method in which they are synthesized. Finding ways to control, or even design, the composition and morphology of nanoalloys could potentially open the door for a standardized approach for creating nanomaterials with unique and desirable …

Bringing The Passion Back: Using Your Expertise To Gain Experience, Improve Motivation, And Create Real Change In Global Agriculture, J.M.D. Motschenbacher

School of Natural Resources: Faculty Publications

No abstract provided.

Preface To "Intertwingled: The Work And Influence Of Ted Nelson", Douglas R. Dechow, Daniele C. Struppa

Mathematics, Physics, and Computer Science Faculty Books and Book Chapters

This is the preface to "Intertwingled: The Work and Influence of Ted Nelson", which examines and honors the work and influence of the computer visionary and re-imagines its meaning for the future. Emerging from a conference held in 2014 at Chapman University, it includes contributions from world-renowned computer scientists and media figures.

The full text of this book is available on an open access basis at Springer.

The blog for the Intertwingled Conference can be read here.

The Logical System Of Frege’S Grundgesetze : A Rational Reconstruction, Méven Cadet, Marco Panza

MPP Published Research

This paper aims at clarifying the nature of Frege's system of logic, as presented in the first volume of the Grundgesetze . We undertake a rational reconstruction of this system, by distinguishing its propositional and predicate fragments. This allows us to emphasise the differences and similarities between this system and a modern system of classical second-order logic.

Pruebas Entimemáticas Y Pruebas Canónicas En La Geometría Plana De Euclides, Marco Panza, Abel Lassalle Casanave

MPP Published Research

Dado que la aplicación del Postulado I.2 no es uniforme en Elementos, ¿de qué manera debería ser aplicado en la geometría plana de Euclides? Además de legitimar la pregunta misma desde la perspectiva de una filosofía de la práctica matemática, nos proponemos esbozar una perspectiva general de análisis conceptual de textos matemáticos que involucra una noción ampliada de la teoría matemática como sistema de autorizaciones o potestades y una noción de prueba que depende del auditorio.

Since the application of Postulate I.2 in the Elements is not uniform, one could wonder in what way should it be applied in Euclid’s …

Infrared Radiography: Modeling X-Ray Imaging Without Harmful Radiation, Otto Zietz, Elliot E. Mylott, Ralf Widenhorn

Physics Faculty Publications and Presentations

Planar x-ray imaging is a ubiquitous diagnostic tool and is routinely performed to diagnose conditions as varied as bone fractures and pneumonia. The underlying principle is that the varying attenuation coefficients of air, water, tissue, bone, or metal implants within the body result in non-uniform transmission of x-ray radiation. Through the detection of transmitted radiation, the spatial organization and composition of materials in the body can be ascertained. In this paper, we describe an original apparatus that teaches these concepts by utilizing near infrared radiation and an up-converting phosphorescent screen to safely probe the contents of an opaque enclosure.

Quantitative Modeling Of The Equilibration Of Two-Phase Solid-Liquid Fe By Atomistic Simulations On Diffusive Time Scales, Ebrahim Asadi, Mohsen Asle Zaeem, Sasan Nouranian, Michael I. Baskes

Materials Science and Engineering Faculty Research & Creative Works

In this paper, molecular dynamics (MD) simulations based on the modified-embedded atom method (MEAM) and a phase-field crystal (PFC) model are utilized to quantitatively investigate the solid-liquid properties of Fe. A set of second nearest-neighbor MEAM parameters for higherature applications are developed for Fe, and the solid-liquid coexisting approach is utilized in MD simulations to accurately calculate the melting point, expansion in melting, latent heat, and solid-liquid interface free energy, and surface anisotropy. The required input properties to determine the PFC model parameters, such as liquid structure factor and fluctuations of atoms in the solid, are also calculated from MD …

Weakness In Numbers: A Brief Introduction, Ryan G. Ganzenmuller, Matthew A. Eldred

Buffalo Law Review

No abstract provided.