Physical Sciences and Mathematics Commons^™

Morphology And Conformation Of Polythiophene Derivatives In Anisotropic Core-Shell Nanocomposites And Solution, Neil Redeker

Master's Theses

Conjugated semiconducting polymers have garnered substantial interest in recent years due to the potential for use in various applications, particularly in the field of electronic devices such as photovoltaic cells and light emitting diodes. Conjugated polymers offer numerous advantages in these applications, including low cost and high flexibility, but electronic devices based on these materials are currently limited by poor performance. Because of these limitations, increased focus has been placed on improving conjugated polymers for use in commercially viable products. Here, a novel core shell hybrid nanocomposite based on anisotropic zinc oxide nanowires and a side-chain functionalized polythiophene is reported. …

Computing Curvature And Curvature Normals On Smooth Logically Cartesian Surface Meshes, John Thomas Hutchins

Boise State University Theses and Dissertations

This thesis describes a new approach to computing mean curvature and mean curvature normals on smooth logically Cartesian surface meshes. We begin by deriving a finite-volume formula for one-dimensional curves embedded in two- or three- dimensional space. We show the exact results on curves for specific cases as well as second-order convergence in numerical experiments. We extend this finite-volume formula to surfaces embedded in three-dimensional space. Exact results are again derived for special cases and second-order convergence is shown numerically for more general cases. We show that our formula for computing curvature is an improvement over using the “cotan” formula …

Estimation And Inference For Spatial And Spatio-Temporal Mixed Effects Models, Casey M. Jelsema

Dissertations

One of the most common goals of geostatistical analysis is that of spatial prediction, in other words: filling in the blank areas of the map. There are two popular methods for accomplishing spatial prediction. Either kriging, or Bayesian hierarchical models. Both methods require the inverse of the spatial covariance matrix of the data. As the sample size, n, becomes large, both of these methods become impractical. Reduced rank spatial models (RRSM) allow prediction on massive datasets without compromising the complexity of the spatial process. This dissertation focuses on RRSMs, particularly situations where the data follow non-Gaussian distributions.

The manner in …

Assessing Different Zeolitic Adsorbents For Their Potential Use In Kr And Xe Separation, Breetha Alagappan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Separation of Kr from Xe is an important problem in spent nuclear fuel fission gas management. The energy intensive and expensive cryogenic distillation method is currently used to separate these gases. In this thesis, we have carried out the research into appropriate sorbents for the separation of Kr and Xe using pressure swing adsorption. We have examined zeolites using gas adsorption studies as they have the potential to be more cost effective than other sorbents. Zeolites are microporous aluminosilicates and have ordered pore structures. The pores in zeolites have extra-framework cations are substantially free to move. The mobility of cations …

Local Influence In Bayesian Elliptically Contoured-Ordinal Model For Mixed Data, Ehsan B. Samani

Applications and Applied Mathematics: An International Journal (AAM)

This paper develops a new class of joint modeling of mixed correlated ordinal and continuous responses with elliptically contoured errors. This joint model includes the latent variable approach of using an elliptically contoured distribution for mixed ordinal and continuous responses. A Markov Chain Monte Carlo sampling algorithm is described for estimating the posterior distribution of the parameters. For sensitivity analysis to investigate the perturbation from associate responses, it is demonstrated how one can use some elements of covariance structure. Influence of small perturbation of these elements on the posterior normal curvature is also studied. To illustrate the application of such …

The Underlying Physiology Of Arterial Pulse Wave Morphology In Spatial Domain, Nzerem F. Egenti, Alozie H. Nkechi

Applications and Applied Mathematics: An International Journal (AAM)

Cardio-vascular events are among the world’s leading causes of morbidity and mortality. Most postulates suppose that culinary delights can be implicated in incidences of cardio-vascular diseases. This school of thought holds well in many respects. Much as the truistic value of the said school is acknowledged, we conceived of physiological disposition as an endogenous dominant factor in the events being considered, whereas culinary measures constitute an exogenous contributory factor. In this work we aimed at studying the effects of distance (stature) on pulse waveforms. Certain elements of our study showed that pulse wavelength was dominant in prescribing cardio-vascular physiology.

Reducibility Of Eulerian Graphs And Digraphs, Akram B. Attar

Applications and Applied Mathematics: An International Journal (AAM)

In this paper the concept of reducibility in graph theory is discussed, and the deletable vertex (edge) in graph (digraph) is defined. The class of graphs (digraphs) ℛ is called vertex (edge) reducible if for any G∈ ℛ either ℛ is the trivial graph (null graph) or it contains a vertex (edge) v such that G-v∈ ℛ. We introduce some classes of graphs (digraphs) which are reducible and others which are not. The vertex reducibility and edge reducibility of Eulerian graphs and Eulerian digraphs have also been studied.

Some Geometric Properties Of A New Type Metric Space, Muhammed Çınar, Murat Karakaş, Mikail Et

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we define a metric on our new space and then show that this linear metric space is k-nearly uniform convex and has property beta where p = p_k is a bounded sequence of positive real numbers. Finally, we give a result about property (H) by using k-nearly uniform convexity.

Graphic Illustration Of The Transmission Resonances For The Dkp Particles, B. Boutabia-Chéraitia, Abdenacer Makhlouf

Applications and Applied Mathematics: An International Journal (AAM)

We consider the Duffin-Kemmer-Petiau (DKP) equation in the presence of a spatially one-dimensional Woods-Saxon (WS) potential and we show by graphics how the zero-reflection condition on the Klein interval depends on the shape of the potential.

Obstacles And Solutions To Studying Functional Adhesives Using Vibrational Sum-Frequency Generation Spectroscopy, Angela Renee Andersen

Theses and Dissertations

Important aspects of adhesion occur at interfaces, including structures that may be different from those in the bulk materials. However, probing the orientation of molecules in functional adhesives poses a significant challenge because adhesive molecules are always located at a buried interface. The limited penetration depth of surface-specific analysis prohibits the study of buried interfaces using those techniques. The large quantity of bulk molecules relative to the adhesive molecules interacting at the interface results in the bulk signal swamping out adhesive signal in bulk analysis techniques. An interface-specific technique is required to study functional adhesives. One such technique that has …

Surface Shape Perception In Volumetric Stereo Displays, Meng Zhu

All Dissertations

In complex volume visualization applications, understanding the displayed objects and their spatial relationships is challenging for several reasons. One of the most important obstacles is that these objects can be translucent and can overlap spatially, making it difficult to understand their spatial structures. However, in many applications, for example medical visualization, it is crucial to have an accurate understanding of the spatial relationships among objects. The addition of visual cues has the potential to help human perception in these visualization tasks. Descriptive line elements, in particular, have been found to be effective in conveying shape information in surface-based graphics as …

Exploratory Synthesis Of New Iron(Ii,Iii)-Containing Polyanion Framework Solids Of Electrochemical And Magnetic Interest, Liurukara Sanjeewa

All Dissertations

The studies demonstrated in this dissertation were primarily focused on the synthesis, structure and property characterizations of iron(II,III) containing framework solids. The scope of this research is threefold: 1) explore new iron(II, III)-containing open framework structures in hopes of creating new materials, useful in the areas of both Li- and Na-ion battery applications; 2) synthesis and characterization of low-dimensional magnetic nanostructures exhibiting novel magnetic properties due to confined magnetic lattices; and 3) conduct structure/property correlation studies to identify the origins of any unusual physical phenomena associated with these new compounds.

In the syntheses of new compounds, molten salt fluxes were …

The Update, December 2013, University Of Northern Iowa. College Of Humanities, Arts And Sciences.

Update

Inside this issue...

-- Milkweed Seed Harvesting and Prairie Restoration
-- Department News
-- Environmental Science B.A. Degree
-- James Davis Presentation at National Convention
-- School of Music Events
-- UNI Women's & Gender Studies Presents CROW Forum
-- Alumni Spotlight: Physics: Cary Pint
-- Student Spotlight: Philosophy & World Religions: Corey Cooling
-- Featured Organization: UNI Interpreters Theatre
-- Interpreters Theatre Productions Schedule
-- Iowa Teachers Named Finalists for Math, Science
-- UNI Marching Band

Can Clustering Improve Requirements Traceability? A Tracelab-Enabled Study, Brett Taylor Armstrong

Master's Theses

Software permeates every aspect of our modern lives. In many applications, such in the software for airplane flight controls, or nuclear power control systems software failures can have catastrophic consequences. As we place so much trust in software, how can we know if it is trustworthy? Through software assurance, we can attempt to quantify just that.

Building complex, high assurance software is no simple task. The difficult information landscape of a software engineering project can make verification and validation, the process by which the assurance of a software is assessed, very difficult. In order to manage the inevitable information overload …

Fuzzy Search Strategy Generation For Adversarial Systems Using Fuzzy Process Particle Swarm Optimization, Fuzzy Patterns, And A Hunch Factor, Stephany Coffman-Wolph

Dissertations

Adversarial game-playing situations have been studied in both game theory and artificial intelligence since the 1950s. However, developing strategies for game playing is challenging due to the large search tree size as the environment size increases. The research presented develops a centralized fuzzy search strategy to find winning strategies for adversarial situations using fuzzy logic. The aforementioned fuzzy algorithm, Fuzzy Strategy Finder (FSF), can be used to find valid strategies for any problem that can be written as a Reti-like or zero-sum game. Using several chess endgames, the FSF will be shown to have a faster runtime without a significant …

Development Of Polarization Analysis Of Resonant Inelastic X-Ray Scattering, Xuan Gao

Dissertations

Resonant inelastic x-ray scattering (RIXS) is a powerful technique in condensed matter physics for studying the electronic excitations in novel materials of interest. In currently operating hard x-ray RIXS instruments the energy and momentum transfers are measured while the outgoing polarization is not measured due to significant technical challenges. But the outgoing polarization of the scattered photons provides valuable information (excitation symmetry) about the states involved in the scattering which is difficult to determine without polarization analysis. Polarization analysis has proved extremely valuable in soft x-ray RIXS, and so a polarization analysis system is being developed to fill the technical …

Client-Based Qos Monitoring And Evaluation Architecture For Network Infrastructure And Services, Ammar Mohammed Kamel

Dissertations

Providing an efficient Quality-of-Service (QoS) measurement model is a challenging problem in today’s mobile computing and telecommunications networks. Currently, most of QoS techniques utilize service measurements that are collected by the network elements (i.e., network-side monitoring) to evaluate the network performance. However, this process does not take into account the service performance from the clients' perspective and might contradict with the Service Level Agreement (SLA). In order to overcome the limitations of service-side QoS monitoring, a number of research studies have been conducted to present alternative architectures and algorithms for client-side QoS service assessment in computer networks. The client-side QoS …

Tomato Worker Ergonomics: Reba Panel Evaluation Of Job Tasks Using Video., Leaann Nichole Manz

Undergraduate Honors Theses

This project tested the hypothesis that non-experts' rankings of ergonomic stressors differ from those of health professionals. Tennessee ranks fifth in the production of tomatoes, an industry in which stoop labor, hand harvesting, and packing predominate. Specific parts of tomato workers' bodies are at risk of ergonomic injury such as, shoulders (loads), backs (stoop labor), lower extremities (posture), and upper extremities (repetitive motion). Of equal importance is our expectation that the scores assigned by non-experts will correlate with those of experts, leading to a community consensus for action and practical intervention research. Video footage of harvesting and sorting was analyzed …

Application Of Fractional Moments For Comparing Random Variables With Varying Probability Distributions, Munther R. Al Shami, A. R. Mugdadi, R. R. Nigmatullin, S. I. Osokin

Applications and Applied Mathematics: An International Journal (AAM)

New methods are being presented for statistical treatment of different random variables with unknown probability distributions. These include analysis based on the probability circles, probability ellipses, generalized mean values, generalized Pearson correlation coefficient and the beta-function analysis. Unlike other conventional statistical procedures, the main distinctive feature of these new methods is that no assumptions are made about the nature of the probability distribution of the random series being evaluated. Furthermore, the suggested procedures do not introduce uncontrollable errors during their application. The effectiveness of these methods is demonstrated on simulated data with extended and reduced sample sizes having different probability …

The Importance Of Mapping To The Next Generation Retinal Prosthesis, Jonathan Gesell

Student Work

Evolutionarily, human beings have come to rely on vision more than any other sense, and with the prevalence of visual-oriented stimuli and the necessity of computers and visual media in everyday activities, this can be problematic. Therefore, the development of an accurate and fast retinal prosthesis to restore the lost portions of the visual field for those with specific types of vision loss is vital, but current methodologies are extremely limited in scope. All current models use a spatio-temporal filter (ST), which uses a difference of Gaussian (DOG) to mimic the inner layers of the retina and a noisy leak …

An Mpi-Enabled Mapreduce Framework For Molecular Dynamics Simulation Applications, Shuju Bai, Ebrahim Khosravi, Seung Jong Park

Computer Science Faculty Research & Creative Works

Computational technologies have been extensively investigated to be applied into many application domains. Since the presence of Hadoop, an implementation of MapReduce framework, scientists have applied it to biological sciences, chemistry, medical sciences, and other areas to efficiently process huge data sets. Although Hadoop is fault-tolerant and processes data in parallel, it does not support MPI in computing. The Map/Reduce tasks in Hadoop have to be serial, which results in inefficient scientific computations wrapped in Map/Reduce tasks. In the real world, many applications require MPI techniques due to their nature. Molecular dynamics simulation is one of them. In our research, …

Afcd: An Approximated-Fair And Controlled-Delay Queuing For High Speed Networks, Lin Xue, Suman Kumar, Cheng Cui, Praveenkumar Kondikoppa, Chui Hui Chiu, Seung Jong Park

Computer Science Faculty Research & Creative Works

High speed networks have characteristics of high bandwidth, long queuing delay, and high burstiness which make it difficult to address issues such as fairness, low queuing delay and high link utilization. Current high-speed networks carry heterogeneous TCP flows which makes it even more challenging to address these issues. Since sender centric approaches do not meet these challenges, there have been several proposals to address them at router level via queue management (QM) schemes. These QM schemes have been fairly successful in addressing either fairness issues or large queuing delay but not both at the same time. We propose a new …

Context Aware Identity Management Using Smart Phones, Vamsi Paruchuri, Sriram Chellappan

Computer Science Faculty Research & Creative Works

Cell phones are personal devices that are seldom used by more than one individual. Today's smartphone not only serves as the key computing and communication mobile device of choice, but it also comes with a rich set of embedded sensors. In other words, smartphones can be considered less of a "phone" in the traditional sense and more of an identity management device. Furthermore, the unique array of sensors on a smartphone can communicate its owner's identity to the world. Smartphones are pervasive computing devices that ubiquitously accompany humans and must adapt accordingly. In this paper, we propose architecture to fully …

Query-Document-Dependent Fusion: A Case Study Of Multimodal Music Retrieval, Zhonghua Li, Bingjun Zhang, Yi Yu, Jialie Shen, Ye Wang

Research Collection School Of Computing and Information Systems

In recent years, multimodal fusion has emerged as a promising technology for effective multimedia retrieval. Developing the optimal fusion strategy for different modality (e.g. content, metadata) has been the subject of intensive research. Given a query, existing methods derive a unified fusion strategy for all documents with the underlying assumption that the relative significance of a modality remains the same across all documents. However, this assumption is often invalid. We thus propose a general multimodal fusion framework, query-document-dependent fusion (QDDF), which derives the optimal fusion strategy for each query-document pair via intelligent content analysis of both queries and documents. By …

A Local Social Network Approach For Research Management, Xiaoyan Liu, Zhiling Guo, Zhenjiang Lin, Jian Ma

Research Collection School Of Computing and Information Systems

Traditional methods to evaluate research performance focus on citation count, quality and quantity of research output by individual researchers. These measures overlook the roles an individual plays in research collaboration, which is critical in an institutional research management environment due to the inherent interdependency among research entities. In order to address the organizational research management needs, we propose a research social network approach to better analyze local collaboration networks. For this purpose, we develop a new “collaboration supportiveness” measure to quantify an individual researcher's collaboration ability. Insights derived from this research are very helpful for managers to effectively allocate resources, …

Fundamental Limits On End-To-End Throughput Of Network Coding In Multi-Rate And Multicast Wireless Networks, Luiz Felipe Viera, Mario Gerla, Archan Misra

Research Collection School Of Computing and Information Systems

This paper investigates the interaction between network coding and link-layer transmission rate diversity in multi-hop wireless networks. By appropriately mixing data packets at intermediate nodes, network coding allows a single multicast flow to achieve higher throughput to a set of receivers. Broadcast applications can also exploit link-layer rate diversity, whereby individual nodes can transmit at faster rates at the expense of corresponding smaller coverage area. We first demonstrate how combining rate-diversity with network coding can provide a larger capacity for data dissemination of a single multicast flow, and how consideration of rate diversity is critical for maximizing system throughput. Next …

Modeling Temporal Adoptions Using Dynamic Matrix Factorization, Freddy Chong-Tat Chua, Richard Jayadi Oentaryo, Ee Peng Lim

Research Collection School Of Computing and Information Systems

The problem of recommending items to users is relevant to many applications and the problem has often been solved using methods developed from Collaborative Filtering (CF). Collaborative Filtering model-based methods such as Matrix Factorization have been shown to produce good results for static rating-type data, but have not been applied to time-stamped item adoption data. In this paper, we adopted a Dynamic Matrix Factorization (DMF) technique to derive different temporal factorization models that can predict missing adoptions at different time steps in the users' adoption history. This DMF technique is an extension of the Non-negative Matrix Factorization (NMF) based on …

Hibernating Process: Modeling Mobile Calls At Multiple Scales, Siyuan Liu, Lei Li, Ramayya Krishnan

Research Collection School Of Computing and Information Systems

Do mobile phone calls at larger granularities behave in the same pattern as in smaller ones? How can we forecast the distribution of a whole month's phone calls with only one day's observation? There are many models developed to interpret large scale social graphs. However, all of the existing models focus on graph at one time scale. Many dynamical behaviors were either ignored, or handled at one scale. In particular new users might join or current users quit social networks at any time. In this paper, we propose HiP, a novel model to capture longitudinal behaviors in modeling degree distribution …

Pip: Privacy And Integrity Preserving Data Aggregation In Wireless Sensor Networks, Vimal Kumar, Sanjay Kumar Madria

Computer Science Faculty Research & Creative Works

With the exponential rise of pervasive computing applications, data privacy has become much more of an important issue than before. When data is aggregated at each hop in a sensor network, it becomes harder to protect its privacy. A number of privacies preserving data aggregation algorithms have recently appeared for wireless sensor networks (WSNs), very few of them however also address the issue of data integrity along with privacy. Data privacy and integrity are two contrasting objectives to achieve in general. In a privacy preserved data aggregation, it becomes easier for an attacker to inject false data hence, we suggest …

Dynamic Joint Sentiment-Topic Mode, Yulan He, Chenghua Lin, Wei Gao, Kam-Fai Wong

Research Collection School Of Computing and Information Systems

Social media data are produced continuously by a large and uncontrolled number of users. The dynamic nature of such data requires the sentiment and topic analysis model to be also dynamically updated, capturing the most recent language use of sentiments and topics in text. We propose a dynamic Joint Sentiment-Topic model (dJST) which allows the detection and tracking of views of current and recurrent interests and shifts in topic and sentiment. Both topic and sentiment dynamics are captured by assuming that the current sentiment-topic-specific word distributions are generated according to the word distributions at previous epochs. We study three different …