Digital Commons Network^™

Modeling And Analysis Of Grid-Connected Solar-Wind Hybrid Power System, Sultan Altamimi

Dissertations and Theses @ UNI

Renewable energies are considered to be a significant part of the energy mix to assist the existing electricity demand and the future of electrical generation. Electrical power simulation software is increasingly being used to answer and determine the source of potential problems in the actual power system. To have a better understanding of an electrical power system, it is essential to validate all the components through simulation within an environment that allows accurate modeling of all power system components. This research presents modeling and analysis of an actual grid-connected solar-wind hybrid system at University of Northern Iowa campus in Cedar …

Robotic Manufacturing Cell: An Analysis Of Variables Affecting Performance, Elvis Alicic

Dissertations and Theses @ UNI

Analyzing the performance of manufacturing cells is a well established concept. The justification for conducting thorough analyses of manufacturing cells comes from the known advantages it can provide, including performance improvement and production planning improvement, both current and future. This study focuses on assessing the variables affecting performance of a robotic manufacturing cell through the measure of throughput. Initially, simulation modeling is utilized to model an existing robotic cell and compare the output to actual production output from the same cell. Additionally, general regression modeling is employed to analyze the following variables and their effect on throughput: machine downtime, off-plan …

Analysis Of Covert Software Behavior, Zhen Huo

Dissertations and Theses @ UNI

In general, users are isolated from the inner-workings of software. The behavior of software is analogous to a "black box," performing user-directed tasks in a predictable way. But this isolation of the inner-workings can foster both curiosity and suspicion of the goings-on "under the hood," especially when the software is closed-source, as is the case with a majority of commercial software. When talking about behaviors of software from the outside perspective of the end user, concerns are raised about issues including memory leaks, data integrity, confidential, etc. This paper discusses several techniques for scrutinizing and eliciting covert behavior of applications …

Geostatistical Spatiotemporal Modelling With Application To The Western King Prawn Of The Shark Bay Managed Prawn Fishery, Ainslie M. Denham

Theses: Doctorates and Masters

Geostatistical methodology has been employed in the modelling of spatiotemporal data from various scientific fields by viewing the data as realisations of space-time random functions. Traditional geostatistics aims to model the spatial variability of a process so, in order to incorporate a time dimension into a geostatistical model, the fundamental differences between the space and time dimensions must be acknowledged and addressed. The main conceptual viewpoint of geostatistical spatiotemporal modelling identified within the literature views the process as a single random function model utilising a joint space-time covariance function to model the spatiotemporal continuity. Geostatistical space-time modelling has been primarily …

Measuring And Filtering Microwave Radiations Using Frequency Selective Surface Through Energy Saving Glass, Irfan Ullah

Theses: Doctorates and Masters

This thesis presents the results of our investigation into the measurement and filtering of microwave radiation, and the subsequent development of a microwave reduction solution for modern building architecture utilising Energy Saving Glass (ESG), in conjunction with Frequency Selective (FSS) surfaces through which useful signals can be filtered. In the investigation, radiation power density levels arising from the three common microwave sources (radio base stations, mobile phones, and microwave ovens) were measured, and the results were compared with the standards provided by the Australian Radiation Protection and Nuclear Safety Agency. For the radio base stations, the relationship between radiation intensity …

Alignment Of Intended Learning Outcomes, Curriculum And Assessment In A Middle School Science Program, Reid J. Smith

Theses: Doctorates and Masters

This study focused on the intended learning outcomes, curriculum and assessment in the science curriculum offered at a regional independent Middle School in the state of Victoria, Australia. In-school assessment has indicated that the current science curriculum of this Middle School may not develop students' skills in scientific literacy as effectively as intended. One hypothesis to explain this deficit is that there is a misalignment of intended outcomes, curriculum materials and assessment. This study aimed to determine the extent to which the intended curriculum and assessment in this Victorian middle years' science program is aligned to its stated goals and …

Microstructure And Mechanical Properties Of Cold Drawn Steel Wires, Ning Liu

Theses: Doctorates and Masters

Cold drawn eutectoid steel wires have been widely used for a variety of applications, such as suspension bridges, steel cords for automobile tires, and springs. Much research has been done to increase their mechanical strength. With advances in modern production technology, both the drawing speed and the quality of drawn steels have been enhanced. After a careful literature survey, it is obvious that some issues are still controversial. As Y.S. Yang, J.G. Bae and C.G. Park mentioned, the lamellar spacing, thickness and volume fraction of cementites have all reached the nanometer regime, and the conventional theory is not enough to …

Linear-Cavity Tunable Fibre Lasers Employing An Opto-Vlsi Processor And A Mems-Based Device, David Daniel Michel

Theses: Doctorates and Masters

This thesis proposes and demonstrates experimentally two novel linear-cavity tunable fibre lasers employing an erbium-doped fibre (EDF) in conjunction with an Opto- VLSI processor and a MEMS-based device for wavelength selection. The Opto-VLSI processor and the MEMS-based device along with an optical collimator, a Bragg grating plate and an optical lens, enable the realisation of an optical filter for continuous tuning of wavelengths over the amplified spontaneous emission (ASE) range of the EDF. We also propose the use of a section of un-pumped EDF as a saturable absorber (SA), which suppresses noise spikes caused by the high optical pumping power. …

Coevolutionary Algorithms For The Optimization Of Strategies For Red Teaming Applications, Tirtha Ranjeet

Theses: Doctorates and Masters

Red teaming (RT) is a process that assists an organization in finding vulnerabilities in a system whereby the organization itself takes on the role of an “attacker” to test the system. It is used in various domains including military operations. Traditionally, it is a manual process with some obvious weaknesses: it is expensive, time-consuming, and limited from the perspective of humans “thinking inside the box”. Automated RT is an approach that has the potential to overcome these weaknesses. In this approach both the red team (enemy forces) and blue team (friendly forces) are modelled as intelligent agents in a multi-agent …

The Weathering Of Oil After The Deepwater Horizon Oil Spill: Insights From The Chemical Composition Of The Oil From The Sea Surface, Salt Marshes And Sediments, Zhanfei Liu, Jiqing Liu, Qingzhi Zhu, Wei Wu

Faculty Publications

The oil released during the Deepwater Horizon (DWH) oil spill may have both short- and long-time impacts on the northern Gulf of Mexico ecosystems. An understanding of how the composition and concentration of the oil are altered by weathering, including chemical, physical and biological processes, is needed to evaluate the oil toxicity and impact on the ecosystem in the northern Gulf of Mexico. This study examined petroleum hydrocarbons in oil mousse collected from the sea surface and salt marshes, and in oil deposited in sediments adjacent to the wellhead after the DWH oil spill. Oil mousses were collected …

R&D Target-Setting Difficulties Addressed Through Emergent Method: Technology Forecasting Using Data Envelopment Analysis, Ann-Marie Lamb, Timothy R. Anderson, Tugrul Unsal Daim

Engineering and Technology Management Faculty Publications and Presentations

The aim of this study is to provide a foundation for researchers and managers to further discuss and resolve difficulties associated with R&D target-setting. While multiple studies mention the difficulty of R&D target-setting, few studies exist which compile reasons for these difficulties; nor do they address this issue in any detail. This paper provides what appears to be one of the first studies outlining reasons for R&D target-setting difficulties through a literature review; then also provides an initial set of analyses and results after applying an emerging quantitative method, Technology Forecasting Using Data Envelopment Analysis (TFDEA) addressing these difficulties, step-by-step …

An In Vitro Comparative Study Of Intracanal Fluid Motion And Wall Shear Stress Induced By Ultrasonic And Polymer Rotary Finishing Files In A Simulated Root Canal Model, Jon Koch, John Borg, Abby Mattson, Kris Olsen, James Bahcall

Mechanical Engineering Faculty Research and Publications

Objective. This in vitro study compared the flow pattern and shear stress of an irrigant induced by ultrasonic and polymer rotary finishing file activation in an acrylic root canal model. Flow visualization analysis was performed using an acrylic canal filled with a mixture of distilled water and rheoscopic fluid. The ultrasonic and polymer rotary finishing file were separately tested in the canal and activated in a static position and in a cyclical axial motion (up and down). Particle movement in the fluid was captured using a high-speed digital camera and DaVis 7.1 software. The fluid shear stress analysis was …

Northeast Ohio Storm Water Training Consortium Strategic Plan: 2012-2014, Claudette Robey

All Maxine Goodman Levin School of Urban Affairs Publications

No abstract provided.

Fiscal Review Of The Cleveland Public Library And Scan Of State And National Trends In Library Funding, Claudette Robey, Kevin O'Brien, Kyle Julien, Scott Winograd

All Maxine Goodman Levin School of Urban Affairs Publications

No abstract provided.

Review Of The Operations Of Bay Village, Ohio, Daila Shimek, Kyle Julien, Scott Winograd, Claudette Robey, James Wyles, Kevin E. O'Brien

All Maxine Goodman Levin School of Urban Affairs Publications

No abstract provided.

Racial And Ethnic Proportions Of Early In-Person Voters In Cuyahoga County, General Election 2008, And Implications For 2012, Norman Robbins, Mark Salling

All Maxine Goodman Levin School of Urban Affairs Publications

No abstract provided.

Who Is Afraid Of Perpetual Trusts?, Bridget J. Crawford

Elisabeth Haub School of Law Faculty Publications

Professor Lawrence Waggoner nominally aims his critique at wealthy individuals who desire perpetual trusts and the lawmakers who enable them by passing favorable legislation. He lodges five specific objections: (1) after a certain period of time, the beneficiaries of perpetual trusts will be insufficiently related to the trust creator; (2) after a certain period of time, there will be too many beneficiaries of a perpetual trust; (3) perpetual trusts will be expensive to manage; (4) outdated trust instruments will hamper management of perpetual trusts; and (5) trustee turnover will negatively impact perpetual trusts. This Essay considers each of his objections …

Critical Bifocality And Circuits Of Privilege: Expanding Critical Ethnographic Theory And Design, Lois Weis, Michelle Fine

Publications and Research

Almost 10 years ago, in Working Method (2004), we argued for a critical theory of method for educational studies, which would analyze lives in the context of history, structure, and institutions, across the power lines of privilege and marginalization.

History, Interactive Technology And Pedagogy: Past Successes And Future Directions, Stephen Brier

Publications and Research

Based on a keynote presentation at the 2012 Canadian Historical Association conference, this paper surveys the state of digital technology and its impact on academic publication and teaching in the contemporary university. Focusing on the dramatic rise of the Digital Humanities in the last few years, the paper examines alternative forms of peer review, academic scholarship and publication, and classroom teaching as they have been reshaped by the adoption of a variety of digital technologies and formats, including open-access, online peer reviewing, use of data- bases and visualization techniques in humanities work, online journal publication, and the use of blogs …

Where’S The Pedagogy? The Role Of Teaching And Learning In The Digital Humanities, Stephen Brier

Publications and Research

The Digital Humanities (DH) has focused narrowly on digital research methods and projects and digital publication efforts. Yet DH has also had a significant, if under recognized, impact on classroom pedagogy. This chapter evaluates the ways DH practices, embodied in a series of pedagogy projects at the City University of York (CUNY), have been used to reshape teaching and learning in college classrooms.

Parallel Sorting On A Spatial Computer, Max Orhai, Andrew P. Black

Computer Science Faculty Publications and Presentations

We describe a parallel sort for a spatial computer that requires minimal communication. We show simulations of the sort in 1 and 2 dimensions.

Presentation slides are located below in the Additional Files

Patterns As Objects In Grace, Andrew P. Black, Michael Homer, James Noble, David J. Pearce, Kim B. Bruce

Computer Science Faculty Publications and Presentations

Object orientation and pattern matching are often seen as conflicting approaches to program design. Object oriented programs place type-dependent behaviour inside objects and invoke it via dynamic dispatch, while pattern matching programs place type-dependent behaviour outside data structures and invoke it via multiway conditionals (case statements). Grace is a new, dynamic, object-oriented language designed to support teaching: to this end, Grace needs to support both styles. In this paper we explain how this conflict can be resolved gracefully: by modelling patterns and cases as partial functions, reifying those functions as first-class objects, and then building up complex patterns from simpler …

Instability In A Generalized Keller–Segel Model, Patrick De Leenheer, Jay Gopalakrishnan, Erica Zuhr

Mathematics and Statistics Faculty Publications and Presentations

We present a generalized Keller–Segel model where an arbitrary number of chemical compounds react, some of which are produced by a species, and one of which is a chemoattractant for the species. To investigate the stability of homogeneous stationary states of this generalized model, we consider the eigenvalues of a linearized system. We are able to reduce this infinite dimensional eigenproblem to a parametrized finite dimensional eigenproblem. By matrix theoretic tools, we then provide easily verifiable sufficient conditions for destabilizing the homogeneous stationary states. In particular, one of the sufficient conditions is that the chemotactic feedback is sufficiently strong. Although …

Mixed Finite Element Approximation Of The Vector Laplacian With Dirichlet Boundary Conditions, Douglas N. Arnold, Richard S. Falk, Jay Gopalakrishnan

Mathematics and Statistics Faculty Publications and Presentations

We consider the finite element solution of the vector Laplace equation on a domain in two dimensions. For various choices of boundary conditions, it is known that a mixed finite element method, in which the rotation of the solution is introduced as a second unknown, is advantageous, and appropriate choices of mixed finite element spaces lead to a stable, optimally convergent discretization. However, the theory that leads to these conclusions does not apply to the case of Dirichlet boundary conditions, in which both components of the solution vanish on the boundary. We show, by computational example, that indeed such mixed …

Wavenumber Explicit Analysis Of A Dpg Method For The Multidimensional Helmholtz Equation, Leszek Demkowicz, Jay Gopalakrishnan, Ignacio Muga, Jeffrey Zitelli

Mathematics and Statistics Faculty Publications and Presentations

We study the properties of a novel discontinuous Petrov Galerkin (DPG) method for acoustic wave propagation. The method yields Hermitian positive definite matrices and has good pre-asymptotic stability properties. Numerically, we find that the method exhibits negligible phase errors (otherwise known as pollution errors) even in the lowest order case. Theoretically, we are able to prove error estimates that explicitly show the dependencies with respect to the wavenumber ω, the mesh size h, and the polynomial degree p. But the current state of the theory does not fully explain the remarkably good numerical phase errors. Theoretically, comparisons are made with …

The Evil Technology Hypothesis: A Deep Ecological Reading Of International Law, Ugo Mattei, Luigi Russi

Faculty Scholarship

No abstract provided.

A Class Of Discontinuous Petrov–Galerkin Methods. Part Iii: Adaptivity, Leszek Demkowicz, Jay Gopalakrishnan, Antti H. Niemi

Mathematics and Statistics Faculty Publications and Presentations

We continue our theoretical and numerical study on the Discontinuous Petrov–Galerkin method with optimal test functions in context of 1D and 2D convection-dominated diffusion problems and hp-adaptivity. With a proper choice of the norm for the test space, we prove robustness (uniform stability with respect to the diffusion parameter) and mesh-independence of the energy norm of the FE error for the 1D problem. With hp-adaptivity and a proper scaling of the norms for the test functions, we establish new limits for solving convection-dominated diffusion problems numerically: for 1D and for 2D problems. The adaptive process is fully automatic and starts …

Comparing Middle School Students' Learning And Attitudes In Face-To-Face And Online Mathematics Lessons, Clayton M. Edwards

Dissertations and Theses @ UNI

Online learning has become a staple within education for college students, and has started to enter high schools. While this instructional delivery system has been shown to work for older students, few studies have involved middle school students. If this trend toward online teaching of younger students continues, online learning could become a large part of education for middle school students, making research in this area important.

Multiple positive and negative aspects have been identified for online learning. Positive characteristics include individualized pacing; electronic resources, and the opportunity for rapid or personalized feedback, while negative aspects address increased student responsibility …

The Differences In Reading Readiness Among Kindergartners Who Attended State And Federally Funded Pre-K In Alabama, Kelli Tucker

Doctoral Dissertations and Projects

This causal comparative study sought to examine differences in reading readiness of kindergarteners who attended public school pre-k, both state and federally funded. Scores were examined for a convenience sample of 131 students who attended pre-k in the 2007-08 and 2008-09 school years in a school system in east central Alabama. The DIBELS were used to gather kindergarten data in order to examine significant differences in reading readiness. MANCOVA was used to analyze the data for significant differences. The results indicated there were no significant differences, after a full year in kindergarten, in reading readiness of children who attended state …

Top-Down Estimate Of Dust Emissions Through Integration Of Modis And Misr Aerosol Retrievals With The Geos-Chem Adjoint Model, Jun Wang, Xiaoguang Xu, Daven K. Henze, Jing Zeng, Qiang Ji, Si-Chee Tsay, Jianping Huang

Department of Earth and Atmospheric Sciences: Faculty Publications

Predicting the influences of dust on atmospheric composition, climate, and human health requires accurate knowledge of dust emissions, but large uncertainties persist in quantifying mineral sources. This study presents a new method for combined use of satellite-measured radiances and inverse modeling to spatially constrain the amount and location of dust emissions. The technique is illustrated with a case study in May 2008; the dust emissions in Taklimakan and Gobi deserts are spatially optimized using the GEOSChem chemical transport model and its adjoint constrained by aerosol optical depth (AOD) that are derived over the downwind dark-surface region in China from MODIS …