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Instabilities In Nematic Liquid Crystal Films And Droplets, Michael-Angelo Y.-H. Lam

Dissertations

The dynamics of thin films of nematic liquid crystal (NLC) are studied. Nematic liquid crystals are a type of non-Newtonian fluid with anisotropic viscous effects (due to the shape of the molecules) and elasticity effects (due to interacting electrical dipole moments). Exploiting the small aspect ratio in the geometry of interest, a fourth-order non-linear partial differential equation is used to model the free surface of the thin films. Particular attention is paid to the interplay between the bulk elasticity and the preferred orientation (boundary condition) of NLC molecules at the two interfaces: the substrate and the free surface. This work …

Virtual Smarts - Optimizing The Coalescing Of People For Collective Action Within Urban Communities, Stephen Thomas Ricken

Dissertations

Despite the importance of individuals coming together for social group-activities (e.g., pick-up volleyball), the process by which such groups coalesce is poorly understood, and as a consequence is poorly supported by technology. This is despite the emergence of Event-Based Social Network (EBSN) technologies that are specifically designed to assist group coalescing for social activities. Existing theories focus on group development in terms of norms and types, rather than the processes involved in initial group coalescence. This dissertation addresses this gap in the literature through four studies focusing on understanding the coalescing process for interest-based group activities within urban environments and …

Fluorescent Probes And Functionalized Nanoparticles For Bioimaging: Synthesis, Photophysical Properties And Applications, Xinglei Liu

Dissertations

The development of new organic molecular probes with excellent photophysical properties and high fluorescence quantum yields is of considerable interest to many research areas including one- and two-photon fluorescence microscopy, fluorescence-based sensing methodologies, and cancer therapy. Series of organic linear-/non-linear optical molecules including squaraine derivatives, and fluorene derivatives as well as other bioconjugates are designed and synthesized during the doctoral study for the aim of ion detection (Chapter 5), photo dynamic therapy, and deep-tissue imaging (Chapter 4). These optical probes are capable of absorbing light in the near infrared (NIR) window and thus have deeper penetration and cause less photodamage …

Direct And Indirect Controls On Bee Community Composition, Caroline Marie Devan

Dissertations

Bees are important pollinators, critical for the continued survival of plants in both natural and agricultural ecosystems. Diverse bee communities have been shown to increase richness in plant communities and plant reproduction depends upon bee community richness. Yet there is growing concern that pollinators, especially bees, are declining globally. This dissertation focuses on evaluating the mechanisms responsible for bee community composition in order to promote bee conservation in natural systems and their restoration in human-dominated urban and agricultural landscapes.

Bee populations are impacted directly by three things: floral resources, nesting resources and risk, primarily from natural enemies. Bees are indirectly …

Kinetic Study Of Free Radical-Radical Reactions Of Combustion Importance At Elevated Pressures, Chao Yan

Dissertations

Combustion mechanisms consist of hundreds elementary reactions of free radicals and stable molecules. Radical-radical elementary reactions play important roles due to the high concentration in which free radicals are accumulated in combustion systems. Radical-radical reactions are typically multi-channel. Some of the channels might be of chain propagation or even chain branching nature, while other channels might be of chain termination nature. The relative importance of different channels is pressure dependent. Compared to radical-molecule reactions, radical-radical reactions are much less studied. This is due to the difficulties of well characterized quantitative production of radical species as well as due to the …

Structural Studies To Determine The Mechanisms Supporting Multiferroic And Ferroelectric Properties Of Complex Oxides, Han Zhang

Dissertations

Multiferroics are a class of materials which possess both magnetic and electrical polarization with possible coupling between them. They show promise to enable new sensors and data storage devices with novel features, such as the possibility of writing polarization bits with magnetic fields at low power. The coexisting magnetic and ferroelectric order parameters are usually weakly coupled, preventing practical use. The development and study of new classes of materials with large magnetoelectric couplings is of high importance. Understanding the structure of these materials is key to this effort.

As one class of these systems, the RX3(BO₃)₄ has …

High Performance Cloud Computing On Multicore Computers, Jianchen Shan

Dissertations

The cloud has become a major computing platform, with virtualization being a key to allow applications to run and share the resources in the cloud. A wide spectrum of applications need to process large amounts of data at high speeds in the cloud, e.g., analyzing customer data to find out purchase behavior, processing location data to determine geographical trends, or mining social media data to assess brand sentiment. To achieve high performance, these applications create and use multiple threads running on multicore processors. However, existing virtualization technology cannot support the efficient execution of such applications on virtual machines, making them …

Experiments And Multi-Field Modeling Of Inelastic Soft Materials, Shuolun Wang

Dissertations

Soft dielectrics are electrically-insulating elastomeric materials, which are capable of large deformation and electrical polarization, and are used as smart transducers for converting between mechanical and electrical energy. While much theoretical and computational modeling effort has gone into describing the ideal, time-independent behavior of these materials, viscoelasticity is a crucial component of the observed mechanical response and hence has a significant effect on electromechanical actuation. This thesis reports on a constitutive theory and numerical modeling capability for dielectric viscoelastomers, able to describe electromechanical coupling, large- deformations, large-stretch chain-locking, and a time-dependent mechanical response. This approach is calibrated to the widely-used …

Hypoxic And Viral Contributions To The Etiopathogenesis Of Schizophrenia: A Whole Transcriptome Analysis, Kathryn A. Gorski

Theses

Schizophrenia is a mental illness with a complex and as of yet unclear etiology. It is highly heritable and has a strong polygenic character, however, studies examining the genetics of schizophrenia have not sufficiently explained all variability in its prevalence. Environmental causes are theorized to have a non trivial contribution to the pathoetiology of schizophrenia, including interactions with genetic components, but these mechanisms remain unclear. Analyzing schizophrenia dysfunction using transcriptomic approaches is a paradigm still in its infancy, and fewer studies still have examined non neurological contributions to schizophrenia pathology with next generation sequencing technologies. This pilot study uses several …

Intense Ultrasonic Waves In Fluids: Nonlinear Behaviour, Jitendra Kewalramani

Theses

High-intensity ultrasonic wave has several engineering, biological, medical and chemical applications. High intensity acoustic waves can lead to a desired change in a medium by initiating one or more diverse mechanisms such as acoustic cavitation, heating, radiation pressure, or chemical reactions. Nonlinear nature of intense acoustic waves opens an entire new spectrum of applications. Hence there is need to understand and model the mechanism of nonlinear wave motion for practical applications of intense acoustic waves.

In this research, one-dimensional motion of shock waves in an ideal fluid is studied to include nonlinearity. In nonlinear acoustics, the propagation velocity of different …

Modelling Of Oxygen Diffusion In Cork, Swapnil Shivputra Rane

Theses

The primary objective of this project is to better understand gas diffusion through natural cork structures by comparing simulations of gas diffusion through natural cork to experimental measurements of oxygen gas diffusion through the same structure. The cork's internal structure is measured using x-ray computed tomography (CT). From the measured internal structure, a simple mapping is assumed converting the measured x-ray computed tomography images into a 3D map of local diffusion coefficient. Specifically, it is assured that the x-ray CT pixel value is inversely proportional to the diffusion coefficient of oxygen through the cork. A diffusion model for the cork …

Detecting And Characterizing Self Hiding Behavior In Android Applications, Raina Samuel

Theses

Applications (apps) that conceal their activities are fundamentally deceptive; app marketplaces and end-users should treat such apps as suspicious. However, due to its nature and intent, activity concealing is not disclosed up-front, which puts users at risk. This study focuses on characterization and detection of such techniques, e.g., hiding the app or removing traces, known as 'self hiding' (SH) behavior. SH behavior has not been studied per se - rather it has been reported on only as a byproduct of malware investigations. This gap is addressed via a study and suite of static analyses targeted at SH in Android apps. …

Head Impacts In The A7fl, Stephen Mcgeever

Theses

The American 7s Football League (A7FL) is a semi professional football league that does not use helmets or pads. The theory is that the game is safer without helmets and pads because players feel more vulnerable and use a different tackling technique to protect themselves. Rather than lowering and leading with their head when the players tackle, as many helmeted football players do, A7FL players primarily use their arms to wrap the opponent up. A7FL players were given Vector mouth guards designed by Athlete Intelligence to wear. These mouth guards have built in tri-axial accelerometers to record impact data, which …

Knowledge Management In New Product Development (Npd), Luca Maria Mancinelli

Theses

This thesis analyses features that, in New Product Development process (NPD), foster knowledge, and their contribution to the creation and application of knowledge with the aim of increasing both global performance and organizational effectiveness. Since knowledge is becoming more important to achieve competitive advantage, companies have already started to focus on their ability to generate new competencies and create new opportunities for producing new knowledge.

One of the issues compelling knowledge management understands what aspects of the organization's work system and organizational design affect its ability to acquire, create and apply knowledge. In fact, the way that workers are organized …

Electric-Field Assisted Manipulation And Self-Assembly Of Particle Suspensions, Edison Chijioke Amah

Dissertations

The aim of this dissertation is to model the processes by which particles suspended in liquids and at liquid surfaces self-assemble when they are subjected to uniform and non-uniform electric fields. To understand the role of electric forces, three related problems were studied numerically and experimentally.

In the first problem, particles are assumed to be suspended inside a liquid and a nonuniform electric field is applied using electrodes mounted in the domain walls which causes positively polarized particles to collect in the regions where the electric field intensity is locally maximal and the negatively polarized particles collect in the regions …

Supporting User Evaluation Of Messaging Interactions With Potential Romantic Partners Discovered Online, Douglas Zytko

Dissertations

Online dating systems have transformed the way people pursue romance. To arrive at a decision to meet for a face-to-face date, users gather information about each other online pertinent to romantic attraction. Yet sometimes they discover on the date that they made the wrong choice. One aspect of online dating system-use that may be a contributing factor, but is largely overlooked in the literature, is interaction through text-based messaging interfaces. This dissertation explores how messaging interactions inform face-to-face meeting decisions through two qualitative studies, and explores through a mixed methods field study how innovative messaging interfaces that embody theory from …

Mech 237-101-103: Strength Of Materials, Elizabeth Castro

Civil and Environmental Engineering Syllabi

No abstract provided.

Evsc 381-001: Geomorphology, Nancy Jackson

Chemistry, Environmental and Forensic Science Syllabi

No abstract provided.

Chem 236-001: Physical Chemistry For Chemical Engineers, Alisa Krishtal

Chemistry, Environmental and Forensic Science Syllabi

No abstract provided.

Passive Planar Terahertz Retroreflectors, Dhruvkumar Desai

Theses

As the application of the Terahertz (THz) band (0.1 - 10 THz) is investigated in various settings, wireless communication stands out as an important frontier to explore. The benefits of increased bandwidth and data rates it promises will only be realized if new technology is developed to support it. Specifically, since THz wireless communication links are typically line-of-sight (LoS), the LoS can be blocked by moving obstacles, thereby requiring alternative link paths. One proposed solution for indoor wireless communications involves systems of steerable antennas, reflective "wallpaper", and steerable mirrors which would redirect THz beams around a blocking obstacle.

As an …

Leadership And Isteam For Females In Elementary Schools (Life): An Integrated Approach To Increase The Number Of Women Pursuing Careers In Stem, Bruce G. Bukiet, James Lipuma, Nancy Steffen-Fluhr

STEM for Success Resources

2018 Poster presentation for the Leadership and iSTEAM for Females in Elementary Schools (LiFE), project, NJIT

Numerical Methods And Simulation For Time Dependent Electrokinetic Flow, Rui Cao

Dissertations

Electrokinetic flow typically occurs when an electric field is applied to a fluid electrolyte in the presence of a boundary or interface. The electric field induces a force that causes oppositely charged ions to migrate in opposite directions while simultaneously diffusing due to Brownian motion. In an unbounded medium this process, which is called electrodiffusion, does not separate bulk electric charge into separate regions and causes no bulk motion of the host fluid solvent. However, in the presence of a boundary or interface that either impedes or is impervious to the movement of ions in the normal direction, the normal …

Characteristics Of Different Deep Neural Networks And Application Of Pre-Trained Model Without Transfer Learning, Zhiqi Peng

Theses

Deep neural networks have been successful in many areas, some of them even surpass human performances. The goal of this thesis is using data simulations to present different characteristics of three deep neural networks: fully connected deep neural network, convolutional neural network, recurrent neural network, which will perform best when dealing with different feature patterns. By using these characteristics to design a deep neural network on top of an adopted pre-trained model with untrainable layers, achieved an averagely 11.1% improvement than a model with transfer learning method.

Electrical Properties Of Metal Semiconductor Contacts - Metals On Mos2: A Case Study, Xiao Chang

Theses

Properties of monolayer semiconductor, MoS2, are presented in the research. Schottky barrier height and Schottky-Mott rules are discussed. The current-voltage measurement and capacitance-voltage measurement are analyzed considering the role of the work function. We mainly focus on metal semiconductor contacts on molybdenum disulfide (MoS2). The properties of bulk and monolayer molybdenum disulfide are discussed. The differences between the bulk and monolayer, based on band gap structure theory, are presented. Utilizing the data obtained in the literature, the influence of temperature on the electrical properties of monolayer molybdenum disulfide are analyzed. In particular, the electrical properties of metals on MoS2 such …

Looping Predictive Method To Improve Accuracy Of A Machine Learning Model, Subramanyam Reddy Pogili

Theses

The topic of this project is an analysis of drug-related tweets. The goal is to build a Machine Learning Model that can distinguish between tweets that indicate drug abuse and other tweets that also contain the name of a drug but do not describe abuse. Drugs can be illegal, such as heroin, or legal drugs with a potential of abuse, such as painkillers. However, building a good Machine Learning Model requires a large amount of training data. For each training tweet, a human expert has determined whether it indicates drug abuse or not. This is difficult work for humans. …

Evaluating The Impact Of Adopting 3d Printing Services On The Retailers, Sharareh Rajaei Dehkordi

Dissertations

As additive manufacturing technology becomes more responsive to consumers’ demand, one important question for the retailers is whether they should provide 3D printing services in their brick-and-mortar store in addition to the traditional off-the-shelf product? If so, what should be the retailers pricing scheme to achieve a higher profit? What should be the optimal inventory level of off-the-shelf products? What is the optimal capacity of 3D printers? In this study, stochastic models are examined to capture the joint optimal 3D product price and capacity of 3D printers to maximize retailer’s expected profit while considering consumer product choices. Moreover, a stochastic …

Mathematical Models For Polymer-Nematic Interactions, Ensela Mema

Dissertations

This dissertation considers a mathematical model that consists of a nematic liquid crystal layer sandwiched between two parallel bounding plates, across which an external field may be applied. Particular attention is paid to the effect of an applied field on the layer as well as the interaction between the liquid crystal molecules and the molecules of the substrate. The system studied may be considered as a simple model of a Liquid Crystal Display (LCD) device, and the results obtained are discussed and interpreted within this context.

The first part of this dissertation considers a study that investigates how the number …

Appointment Planning And Scheduling In Primary Care, Babak Hoseini

Dissertations

The Affordable Care Act (ACA) puts greater emphasis on disease prevention and better quality of care; as a result, primary care is becoming a vital component in the health care system. However, long waits for the next available appointments and delays in doctors offices combined with no-shows and late cancellations have resulted in low efficiency and high costs.

This dissertation develops an innovative stochastic model for patient planning and scheduling in order to reduce patients’ waiting time and optimize primary care providers’ utility. In order to facilitate access to patients who request a same-day appointment, a new appointment system is …

A Conversation Centric Approach To Understanding And Supporting The Coordination Of Social Group-Activities, Richard P. Schuler

Dissertations

Despite the widespread and large variety of communication tools available to us such as, text messaging, Skype, email, twitter, Facebook, instant messaging, GroupMe, WhatsApp, Snapchat, etc., many people still routinely find coordinating activities with our friends to be a very frustrating experience. Everyone, has at least once, encountered the difficulties involved with deciding what to do as a group. Some friends may be busy, others may have already seen the movie that the others want to see, and some do not like Mexican food. It is a challenge everyone has faced and continue to face. This is a result of …

Biophysical Mechanisms Of Frequency-Dependence And Its Neuromodulation In Neurons In Oscillatory Networks, David Michael Fox

Dissertations

In response to oscillatory input, many isolated neurons exhibit a preferred frequency response in their voltage amplitude and phase shift. Membrane potential resonance (MPR), a maximum amplitude in a neuron’s input impedance at a non-zero frequency, captures the essential subthreshold properties of a neuron, which may provide a coordinating mechanism for organizing the activity of oscillatory neuronal networks around a given frequency. In the pyloric central pattern generator network of the crab Cancer borealis, for example, the pacemaker group pyloric dilator neurons show MPR at a frequency that is correlated with the network frequency. This dissertation uses the crab …