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2019

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Full-Text Articles in Engineering

Estudio De Factibilidad Para La Creación De Una Planta Para El Aprovechamiento De Los Residuos De La Construcción Y Demolición (Rcd) En Bogotá, María Camila Guzmán Malagón, Andrés Felipe Soler Jiménez Jan 2019

Estudio De Factibilidad Para La Creación De Una Planta Para El Aprovechamiento De Los Residuos De La Construcción Y Demolición (Rcd) En Bogotá, María Camila Guzmán Malagón, Andrés Felipe Soler Jiménez

Ingeniería Industrial

El siguiente proyecto tiene como objetivo realizar un estudio de factibilidad, encaminado a la creación de una planta de aprovechamiento de residuos de la construcción y demolición generados en Bogotá, con el fin de suplir de materiales reutilizados y de alta calidad a las empresas constructoras de la ciudad. Para esto se llevó a cabo las fases de un estudio de factibilidad, en primera instancia se realizó un estudio de mercado donde se tuvieron en cuenta todos los actores que intervienen en el mercado, además se hizo una recolección de datos primarios que permitió obtener la demanda que se tendrá ...


An Integrated Framework For Solid Modeling And Structural Analysis Of Layered Composites With Defects, Onur Rauf Bingol, Bryan Schiefelbein, Robert J. Grandin, Stephen D. Holland, Adarsh Krishnamurthy Jan 2019

An Integrated Framework For Solid Modeling And Structural Analysis Of Layered Composites With Defects, Onur Rauf Bingol, Bryan Schiefelbein, Robert J. Grandin, Stephen D. Holland, Adarsh Krishnamurthy

Center for Nondestructive Evaluation Publications

Laminated fiber-reinforced polymer (FRP) composites are widely used in aerospace and automotive industries due to their combined properties of high strength and low weight. However, owing to their complex structure, it is difficult to assess the impact of manufacturing defects and service damage on their residual life. Non-destructive evaluation (NDE) of composites using ultrasonic testing (UT) can identify the presence of defects. However, manually incorporating the damage in a CAD model of a multi-layered composite structure and evaluating its structural integrity is a tedious process. We have developed an automated framework to create a layered 3D CAD model of a ...


Feasibility Investigation Of Upgrading Gravel Road To Otta Seal Surface: An Economic Analysis Approach, Ali Nahvi, Yang Zhang, Ali Arabzadeh, Halil Ceylan, Sunghwan Kim, Charles T. Jahren, Douglas D. Gransberg, Sharif Y. Gushgari Jan 2019

Feasibility Investigation Of Upgrading Gravel Road To Otta Seal Surface: An Economic Analysis Approach, Ali Nahvi, Yang Zhang, Ali Arabzadeh, Halil Ceylan, Sunghwan Kim, Charles T. Jahren, Douglas D. Gransberg, Sharif Y. Gushgari

Civil, Construction and Environmental Engineering Conference Presentations and Proceedings

The Norwegian Road Authorities desired that a surface treatment be cost-effective to provide a faster return on investment, perform (as perceived by the road user) in a manner similar to conventional bituminous surfacing, and comply with the following requirements: • Be cheap and easy to implement • Utilize locally-available aggregates • Be impervious to prevent water incursion into moisture-susceptible base material • Be very flexible, durable, and easy to maintain.

Such a bituminous surface treatment, referred to as in 1963, and initial field trials were carried out during 1963-1965 in the Otta Valley, Norway. Although Nordic countries, Asia, Africa, New Zealand, and South America ...


Mechanical And Aerospace Engineering, 2018-2019, College Of Engineering And Applied Sciences Jan 2019

Mechanical And Aerospace Engineering, 2018-2019, College Of Engineering And Applied Sciences

Mechanical and Aerospace Engineering News

  • Letter from the Chair
  • Introducing Dr. Zachary D. Asher
  • Department of Mechanical and Aerospace Engineering develops an engineering flight simulator
  • Gear Sliding Loss Prediction
  • Ph.D. student receives the prestigious NASA Earth and Space Science Fellowship
  • NSF grant allows important materials research
  • Student receives scholarship from gear industry
  • Development of low cost/high volume micro/nano sensors and actuators
  • Liou receives $204,000 NSF grant for neurological research
  • Alexander Porter inducted into the Alumni Excellence Academy


Charged Nanoparticles Quench The Propulsion Of Active Janus Colloids, Marola W. Issa, Nicky R. Baumgartner, Mohammed A. Kalil, Shawn D. Ryan, Christopher L. Wirth Jan 2019

Charged Nanoparticles Quench The Propulsion Of Active Janus Colloids, Marola W. Issa, Nicky R. Baumgartner, Mohammed A. Kalil, Shawn D. Ryan, Christopher L. Wirth

Mathematics Faculty Publications

Active colloidal particles regularly interact with surfaces in applications ranging from microfluidics to sensing. Recent work has revealed the complex nature of these surface interactions for active particles. Herein, we summarize experiments and simulations that show the impact of charged nanoparticles on the propulsion of an active colloid near a boundary. Adding charged nanoparticles not only decreased the average separation distance of a passive colloid because of depletion attraction as expected but also decreased the apparent propulsion of a Janus colloid to near zero. Complementary agentbased simulations considering the impact of hydrodynamics for active Janus colloids were conducted in the ...


Trapping Aco Applied To Mri Of The Heart, Shannon Lloyd Birchell Jan 2019

Trapping Aco Applied To Mri Of The Heart, Shannon Lloyd Birchell

UNF Graduate Theses and Dissertations

The research presented here supports the ongoing need for automatic heart volume calculation through the identification of the left and right ventricles in MRI images. The need for automated heart volume calculation stems from the amount of time it takes to manually processes MRI images and required esoteric skill set. There are several methods for region detection such as Deep Neural Networks, Support Vector Machines and Ant Colony Optimization. In this research Ant Colony Optimization (ACO) will be the method of choice due to its efficiency and flexibility. There are many types of ACO algorithms using a variety of heuristics ...


Self-Leadership To Servant Leadership: A Metatheoretical Antecedent To Positive Social, Allen Lloyd Carn Jan 2019

Self-Leadership To Servant Leadership: A Metatheoretical Antecedent To Positive Social, Allen Lloyd Carn

Walden Dissertations and Doctoral Studies

A majority of current leadership programs are failing to deliver a comprehensive approach to leadership development by not providing middle and frontline managers the skills to enhance their potential to develop others. In failing to generate a comprehensive system, animosity towards all types of leadership has been festering for over 40 years as first identified by Greenleaf in 1977. The purpose of the study was to establish a link between the theoretical paradigms of servant leadership and self-leadership using the lens of emotional intelligence to generate an integral leadership development framework. The conceptual framework used Goleman et al.'s version ...


Efecto De La Inclusión De Residuo De Tóner En Las Propiedades Mecánicas, Físicas Y Químicas De La Pasta De Cemento, Jorge Andrés Iriarte Chacón, Johan Steve Montenegro Guevara Jan 2019

Efecto De La Inclusión De Residuo De Tóner En Las Propiedades Mecánicas, Físicas Y Químicas De La Pasta De Cemento, Jorge Andrés Iriarte Chacón, Johan Steve Montenegro Guevara

Ingeniería Civil

La investigación e implementación de residuos industriales o de uso general en el sector de la construcción, es un tema de estudio que se ha abordado por más de 40 años, tiempo en el cual se han investigado diversos materiales o residuos de los mismos, buscando darles un uso óptimo, para que de esta forma disminuyan su huella ambiental y contribuyan de alguna forma en la construcción de obras civiles, siendo esta una de las mejores alternativas ya que el cemento es uno de los materiales con más usos en campo, además que aportaría a la reducción de costos del ...


The Incorruptible Integrator: A Streamlined Approach To Imc-Pid Controller Tuning, Sam Wisotzki Jan 2019

The Incorruptible Integrator: A Streamlined Approach To Imc-Pid Controller Tuning, Sam Wisotzki

Graduate College Dissertations and Theses

In automakers' never-ending quest to reduce emissions and improve performance, the turbocharger represents a major step in advancing these goals. By repurposing waste exhaust and compressing the air intake, they are able to increase overall power. One critical control loop in the turbocharger is control of boost pressure via the wastegate. This is a highly nonlinear process and experimental data has shown that a gain-scheduled PID (proportional integral derivative) controller developed with IMC (internal model control) tuning methodology is an effective means to control boost pressure. Motivated by this successful implementation of IMC-PID tuning in the automotive world, this work ...


Optical And Electrical Analysis Of Zno/Znte Micropillar Solar Cells, Sadia Binte Sohid Jan 2019

Optical And Electrical Analysis Of Zno/Znte Micropillar Solar Cells, Sadia Binte Sohid

Master’s Theses

The prime focus of the energy-research community in recent times has been replacing fossil fuels with renewable energy. Therefore, photovoltaic research areas are rapidly expanding in this era. The purpose of this work is to compare three different structural ZnO/ZnTe solar cell types (planar, axial micropillar and radial micropillar). The best optical and electrical performance has been obtained by the radial junction (core-shell) ZnO/ZnTe micropillar solar cell due to its pillar structure and radial junction. The unique advantage of the radial junction micropillar is that the angle of the incident light and the carrier collection is orthogonal. Therefore ...


Testing And Validation Framework For Closed-Loop Physiology Management Systems For Critical And Perioperative Care, Farooq M. Gessa Jan 2019

Testing And Validation Framework For Closed-Loop Physiology Management Systems For Critical And Perioperative Care, Farooq M. Gessa

Master’s Theses

The research aims at developing a framework for testing systems such as closed-loop physiology management systems to ensure that they are safe and effective for use with patients. Building medical devices that are both robust and safe is a challenge. There has been a tremendous increase in modernization and innovation of various medical systems but many of these systems either fail trials or are recalled due to safety issues.

Medical operation rooms require care teams responsible for monitoring the patients and other technical surgical devices. The care process requires a balancing administration that takes care of the drugs and fluids ...


Development Of Physics Based Machine Learning Algorithms, Rob Jennings Jan 2019

Development Of Physics Based Machine Learning Algorithms, Rob Jennings

Master’s Theses

In this study, a baseball pitch was examined to try to understand its behavior, and make a predictive model of it. A baseball pitch was tested experimentally with a wind tunnel and modeled computationally with COMSOL CFD software. Five input variables (spin rate, sting angle, seam orientation: Y axis, seam orientation: Z axis, and air velocity) were controlled, with force in three axes recorded as outputs. The experimental and computational results were examined and seen to be interdependent for all input variables. Experimental and computational data were both insufficient for predicting system behavior. Experimental data collection would have required an ...


Modeling Minority Carrier Transport And Μτ Determination In Cadmium Selenide Thin Film Solar Cells, Benjamin Reichert Jan 2019

Modeling Minority Carrier Transport And Μτ Determination In Cadmium Selenide Thin Film Solar Cells, Benjamin Reichert

Graduate Theses and Dissertations

A simple model for the transport of minority holes in Cadmium Selenide (CdSe) solar cells is presented. Further, via a fitting scheme, the model is shown to permit the subsequent determination of the minority carrier mobility-lifetime (μτ) product in CdSe solar cells.

The mobility-lifetime (μτ) product is an essential characterization parameter in solar cells, and semiconductors in general. For materials such as CdSe, whose diffusion lengths are insufficient to efficiently collect photogenerated carriers, devices must rely on the presence of an internal electric field to aid in collection – in these devices, transport is noted to be “range dominated”.

As the ...


Simulación De Un Controlador Para Un Cuadricóptero Y Sintonización Por Algoritmos Genéticos, Diego Alejandro Perez Acosta Jan 2019

Simulación De Un Controlador Para Un Cuadricóptero Y Sintonización Por Algoritmos Genéticos, Diego Alejandro Perez Acosta

Ingeniería Eléctrica

No abstract provided.


Desarrollo De Un Sistema Para La Generación De Campos Magnéticos Estacionarios Y Homogéneos Con Aplicación En La Estimulación Magnética De Semillas, Jhon Jairo Murcia Zamudio Jan 2019

Desarrollo De Un Sistema Para La Generación De Campos Magnéticos Estacionarios Y Homogéneos Con Aplicación En La Estimulación Magnética De Semillas, Jhon Jairo Murcia Zamudio

Ingeniería Eléctrica

En el desarrollo de este trabajo se presenta un sistema para la generación de campo magnético tipo estacionario espacialmente homogéneo, el cual va dirigido para la aplicación en la estimulación magnéticos de semillas. El sistema que se utiliza como base para la generación del campo magnético, es un arreglo tipo Helmholtz, el cual es un arreglo de 2 bobinas, las cuales han sido dimensionadas y localizadas en el espacio con la finalidad de poder mejorar la homogeneidad en una región determinada del flujo magnético como la magnitud promedio del mismo dentro del volumen de interés. El proceso metodológico que se ...


Parametrización De Un Modelo De Carga Para La Representación De Una Red Con Alta Incidencia De Variadores De Velocidad Tipo Ac4 En Entorno De Simulación, Maria Paula Peña Osuna Jan 2019

Parametrización De Un Modelo De Carga Para La Representación De Una Red Con Alta Incidencia De Variadores De Velocidad Tipo Ac4 En Entorno De Simulación, Maria Paula Peña Osuna

Ingeniería Eléctrica

Este proyecto presenta una estrategia para determinar los parámetros que debe tener un modelo para una carga que cuente con variadores de velocidad tipo AC4, empleando un modelo de recuperación exponencial y que se pueda aplicar en estudios de estabilidad de la tensión de una red de distribución, en un entorno de simulación. Para esto, se implementa un modelo de red eléctrica en Simulink-Matlab que cuenta con la conexión de diversas cargas, entre las cuales esta el variador de velocidad tipo AC4; esta red se somete a fallas trifásicas y se determinan los valores de tensión, potencia activa y reactiva ...


Application Of Droop Control And Synchronization For Single-Phase Inverters In Ac Microgrid Integration, Shuai Yang Jan 2019

Application Of Droop Control And Synchronization For Single-Phase Inverters In Ac Microgrid Integration, Shuai Yang

All Theses, Dissertations, and Other Capstone Projects

With the increasing requirements on environment-friendly and sustainable clean energy [1], people have paid more attention to renewable energy around the world in the past few decades. As a result, power systems have undergone a paradigm shift from centralized generation to distributed generation. Smart grids, which are a combination of power systems and communication networks, were proposed to allow power systems to meet future challenges. In smart grids, especially in AC microgrids, converters play an important role in many areas including microgrid integration, uninterrupted power supply, and flexible alternating current transmission systems. The inverter is a power conversion device [2 ...


Sequence Design Via Semidefinite Programming Relaxation And Randomized Projection, Dian Mo Jan 2019

Sequence Design Via Semidefinite Programming Relaxation And Randomized Projection, Dian Mo

Doctoral Dissertations

Wideband is a booming technology in the field of wireless communications. The receivers in wideband communication systems are expected to cover a very wide spectrum and adaptively extract the parts of interest. The literature has focused on mixing the input spectrum to baseband using a pseudorandom sequence modulation and recovering the received signals from linearly independent measurements by parallel branches to mitigate the pressures from required extreme high sampling frequency. However, a pseudorandom sequence provides no rejection for the strong interferers received together with weak signals from distant sources. The interferers cause significant distortion due to the nonlinearity of the ...


Employing 2-D Cfd & Lrb Model Around Trees To Improve Vawt Placement, David Chukwuebuka Bassey Jan 2019

Employing 2-D Cfd & Lrb Model Around Trees To Improve Vawt Placement, David Chukwuebuka Bassey

All Theses, Dissertations, and Other Capstone Projects

In the placement of vertical axis wind turbines, trees are a constant presence in the vicinity. They are found to grow at different height and shape configurations. And in areas such as the Minnesota State University, Mankato (MNSU) campus, they serve as blockage to airflow; limiting the efficiency of installed turbines. This work sets the precedent for the validation of vegetative numerical models created for the Xcel Energy Research Development Fund (RDF) project.

Using two-dimensional (2-D) numerical simulations of porous cylinders placed in a rectangular medium of air, insight into the flow profile and distribution in the leeward side of ...


A Discrete-Time Technique For Linearity Enhancement Of Wideband Receivers, Mohammad Ghadiri Sadrabadi Jan 2019

A Discrete-Time Technique For Linearity Enhancement Of Wideband Receivers, Mohammad Ghadiri Sadrabadi

Doctoral Dissertations

A new signal processing technique is introduced to enhance the linearity performance of wideband radio frequency (RF) receivers. The proposed technique combines the advancements in mixer first architectures with a library of binary sequences as local oscillator signals to enable wide instantaneous bandwidth and high linearity for the RF receiver. To do so, N-bit pseudo-random-binary-sequences (PRBS) are used as local oscillator signals. The RF input signal is multiplied with the PRBS at the mixer and then averaged over the full sequence. This in effect reduces the amplitude of the signal and improves the overall linearity of the system. In order ...


Evaluation Of The Effect Of Bottom Bar Splice Location On Performance Of Beams In Reinforced Concrete Perimeter Frames, Jorge Rivera Cruz Jan 2019

Evaluation Of The Effect Of Bottom Bar Splice Location On Performance Of Beams In Reinforced Concrete Perimeter Frames, Jorge Rivera Cruz

Doctoral Dissertations

The American Concrete Institute (ACI) Building Code Requirements for Structural Concrete and Commentary (ACI 318-14) indirectly accounts for resistance to progressive collapse by providing requirements for structural integrity in concrete structures. ACI 318-14 structural integrity requirements are intended to provide alternate load paths so that progressive collapse is avoided in the event of the unintended loss of an interior support.

ACI 318-14 §9.7.7.5 requires that splices of structural integrity reinforcement be designed as Class B splices near mid-span for top reinforcement and near the support for bottom reinforcement. However, ACI 318-14 does not provide a clear definition ...


Power System Planning In Disparate Systems: Modeling Sustainability And Electricity Access, Destenie Nock Jan 2019

Power System Planning In Disparate Systems: Modeling Sustainability And Electricity Access, Destenie Nock

Doctoral Dissertations

Electricity goals around the world tend to focus on increasing social benefit through one of two avenues: (1) increasing overall system sustainability or (2) increasing access to electricity. These goals guide the transition of the power system. In pursuit of these goals decision makers will need modeling tools that can inform decisions, in a way that is flexible enough to include a wide range of preferences and goals. It is clear that the future generation mix of the power system will change, but the most sustainable solution, will change based on a country's goals. This dissertation will explore the ...


Mechanical Performance Of Structural Systems With Missing Members: From Buildings To Architected Materials, Panos Pantidis Jan 2019

Mechanical Performance Of Structural Systems With Missing Members: From Buildings To Architected Materials, Panos Pantidis

Doctoral Dissertations

Structural systems are potentially subjected to damage initiating scenarios throughout the course of their service time. Depending on the nature and extent of the damaging event, they may experience significant reduction or even complete loss of their mechanical performance. This dissertation delves into the mechanics of structural systems under the notion of missing members from their domain, investigating types of structural systems: a) multi-story steel framed buildings, and b) materials with a truss-lattice microstructure.

Part I of the dissertation investigates the performance of multi-story steel framed buildings under a column removal scenario, developing an analytical framework for their quasi-static robustness ...


Walking For Object Transport: An Examination Of The Coordinative Adaptations To Locomotor, Perceptual, And Manual Task Constraints, Avelino Amado Jan 2019

Walking For Object Transport: An Examination Of The Coordinative Adaptations To Locomotor, Perceptual, And Manual Task Constraints, Avelino Amado

Doctoral Dissertations

The goal of this dissertation was to understand how the intrinsic dynamics of gait adapt to support the performance of an ecologically relevant object transport task. A common object transport task is walking with a cup of water. Because the water can move relatively independent of the cup, the cup and water system is classified as a complex object. To model this task participants carried a cup with a wooden lid placed on top. On the lid there was a circular region with the same circumference as the cup and a ball. The object of the task was to keep ...


A Topic Modeling Approach For Code Clone Detection, Mohammed Salman Khan Jan 2019

A Topic Modeling Approach For Code Clone Detection, Mohammed Salman Khan

UNF Graduate Theses and Dissertations

In this thesis work, the potential benefits of Latent Dirichlet Allocation (LDA) as a technique for code clone detection has been described. The objective is to propose a language-independent, effective, and scalable approach for identifying similar code fragments in relatively large software systems. The main assumption is that the latent topic structure of software artifacts gives an indication of the presence of code clones. It can be hypothesized that artifacts with similar topic distributions contain duplicated code fragments and to prove this hypothesis, an experimental investigation using multiple datasets from various application domains were conducted. In addition, CloneTM, an LDA-based ...


Reduction Of Nox Emissions In A Single Cylinder Diesel Engine Using Sncr With In-Cylinder Injection Of Aqueous Urea, Anthony Timpanaro Jan 2019

Reduction Of Nox Emissions In A Single Cylinder Diesel Engine Using Sncr With In-Cylinder Injection Of Aqueous Urea, Anthony Timpanaro

UNF Graduate Theses and Dissertations

The subject of this study is the effect of in-cylinder selective non-catalytic reduction (SNCR) of NOx emissions in diesel exhaust gas by means of direct injection of aqueous urea ((NH2)2CO) into the combustion chamber. A single cylinder diesel test engine was modified to accept an electronically controlled secondary common rail injection system to deliver the aqueous urea directly into the cylinder during engine operation.

Direct in-cylinder injection was chosen in order to ensure precise delivery of the reducing agent without the risk of any premature reactions taking place. Unlike direct in-cylinder injection of neat water, aqueous ...


Operational Effectiveness Of Connected Vehicle Smartphone Technology On A Signalized Corridor, Festo Mjogolo Jan 2019

Operational Effectiveness Of Connected Vehicle Smartphone Technology On A Signalized Corridor, Festo Mjogolo

UNF Graduate Theses and Dissertations

Over the last decade, extensive research efforts have been placed on performance evaluation and the benefits of innovative CV applications. Findings indicate that CV technology can effectively mitigate the safety, mobility, and environmental challenges experienced on transportation networks. Most of research evaluated CV technology through simulation studies. However, a field study provides a more ideal method of assessing CV technology effectiveness. Therefore, a field study to obtain the actual effectiveness of CV technology was warranted, to validate previous findings, and to add to the body of knowledge surrounding this topic. This thesis presents both a field study and simulation evaluation ...


The Operational And Safety Effects Of Heavy Duty Vehicles Platooning, Ahmed Alzahrani Jan 2019

The Operational And Safety Effects Of Heavy Duty Vehicles Platooning, Ahmed Alzahrani

UNF Graduate Theses and Dissertations

Abstract

Although researchers have studied the effects of platooning, most of the work done so far has focused on fuel consumption. There are a few studies that have targeted the impact of platooning on the highway operations and safety. This thesis focuses on the impact of heavy-duty vehicles (HDVs) platooning on highway characteristics. Specifically, this study aims at evaluating the effects of platooning of HDVs on capacity, safety, and CO2 emissions.

This study is based on a hypothetical model that was created using the VISSIM software. VISSIM is a powerful simulation software designed to mimic the field traffic flow ...


On Learning And Visualizing Lexicographic Preference Trees, Ahmed S. Moussa Jan 2019

On Learning And Visualizing Lexicographic Preference Trees, Ahmed S. Moussa

UNF Graduate Theses and Dissertations

Preferences are very important in research fields such as decision making, recommendersystemsandmarketing. The focus of this thesis is on preferences over combinatorial domains, which are domains of objects configured with categorical attributes. For example, the domain of cars includes car objects that are constructed withvaluesforattributes, such as ‘make’, ‘year’, ‘model’, ‘color’, ‘body type’ and ‘transmission’.Different values can instantiate an attribute. For instance, values for attribute ‘make’canbeHonda, Toyota, Tesla or BMW, and attribute ‘transmission’ can haveautomaticormanual. To this end,thisthesis studiesproblemsonpreference visualization and learning for lexicographic preference trees, graphical preference models that often are compact over complex domains of ...


Modeling Context-Adaptive Energy-Aware Security In Mobile Devices, Preeti Singh Jan 2019

Modeling Context-Adaptive Energy-Aware Security In Mobile Devices, Preeti Singh

UNF Graduate Theses and Dissertations

As increasing functionality in mobile devices leads to rapid battery drain, energy management has gained increasing importance. However, differences in user’s usage contexts and patterns can be leveraged for saving energy. On the other hand, the increasing sensitivity of users’ data, coupled with the need to ensure security in an energy-aware manner, demands careful analyses of trade-offs between energy and security. The research described in this thesis addresses this challenge by 1)modeling the problem of context-adaptive energy-aware security as a combinatorial optimization problem (Context-Sec); 2) proving that the decision version of this problem is NP-Complete, via a reduction ...