Engineering Commons^™

Performance Evaluation Of Mission Critical Communications Services Over Lte Networks, Kehinde Olumide Olasupo

Theses and Dissertations

he existing Private/Professional Mobile Radio (PMR) technologies designed specifically for Mission Critical Communication (MCC) systems are narrowband and wideband devices, with limited network data capacity in emergency scenarios. They are majorly used to support MCC voice communications and low data rate applications during mission critical operations. However, the need for broadband systems that would support high radio data capacity keep increasing during major incidents and accident scenarios. Because of this, the MCC agencies were attracted by the broadband capabilities of Long Term Evolution (LTE) technology. But, the uplink capacity of LTE- based MCC systems is still a concern. In planning …

Airport Security Investment Model, Joshua Daniel Bolton

Graduate Theses and Dissertations

In an increasingly mobile and diverse world, it is difficult to quantify the risk, or danger, associated with traveling. Airports have suffered greatly for being unable to define potential risks and protect against them. Intelligent adversary risk is a complicated high-level issue for many airports. Airports are targeted because of the large amount of people in a confined space and the social, economic, and psychological impact of terrorist attacks on the American people. In the months following September 11th, 2001, the airline industry in the United States lost $1.1 billion in revenue. The American people stayed grounded, for fear of …

Antibacterial Activity Of Zno Nanoparticles On Silica Thin Film For Wastewater Treatment, S Chanrawangyot, S Rattanachan, A Watcharenwong, T Fangsuwannarak

Journal of Metals, Materials and Minerals

Zinc Oxide nanoparticles on silica matrix thin films were prepared by the Sol-gel method and dip coating on ceramic tiles. In this study, EC (Ethyl cellulose) and TP (alpha-terpineol) used as a binder and a solvent in Sol-gel method, respectively, were studied on the characteristics of thin films. The thin films were dried and calcined at the temperature of 500, 600˚C soaking 30 minutes with the heating rate of 1˚C/minutes. The result of Glancing X-Ray Diffraction showed that thin films were ZnO phase on the amorphous phase of silica matrix. Scanning electron microscope showed the ZnO nanoparticles dispersed on thin …

Properties Of Natural Rubber Latex Filled With Bacterial Cellulose Produced From Pineapple Peels, T Saowapark, E Chaichana, A Jaturapiree

Journal of Metals, Materials and Minerals

Bacterial cellulose (BC) is natural biopolymers with unique properties such as high purity and high tensile strength. These properties considerably support for use as filler in rubber applications. In this research, BC was produced from fermentation by Acetobacter xylinum. Additionally, pineapple peels (agricultural waste) were evaluated for carbon sources in BC's production process. Natural rubber latex (NRL) compound was then incorporated BC with various loadings of 0, 5, 10 and 15 phr (parts per hundred of rubber) for enhancement properties of NRL. Furthermore, NRL filled with BC (NRL-BC) compounds were prevulcanized at 70°C for 2 hours and then NRL-BC sheets …

Physical And Optical Properties Of 20cao-(80-X)B2o3-Xzno Glass System, N Jearnkulprasert, O Chaemlek, N Wantana, J Kaewkhao

Journal of Metals, Materials and Minerals

The 20CaO-(80-x)B2O3-xZnO glasses were prepared by melt quenching technique (where x=0, 5, 15 and 20 mol%) in order to study in the physical and optical properties. These glass compositions were heated to 1200 ºC for 3 hours and annealed at 500ºC for 3 hours. Clear glass samples were obtained from these compositions. The density, molar volume, refractive index, optical spectra (in the wavelength of 190-1100 nm), optical band gap, optical basicity and polarizability of glass samples have been investigated in this work.

Development Of Pre-Stressed Retrofit Strategies For Mitigating Fatigue Cracking In Steel Waterway Lock Gate Components, Christine Michelle Lozano

Graduate Theses and Dissertations

Lock gates are an important part of the transportation infrastructure within the United States (US), having many economic, safety, and environmental benefits over rail and highway transportation systems. Unfortunately, many existing lock gates throughout the US have reached or exceeded their initial design life and require frequent repairs to remain in service. Unscheduled repairs often increase as gates age, having a local economic impact on freight transport which can create economic ripples throughout the nation. Fatigue and corrosion are key causes of unscheduled service interruptions, degrading lock gate components over time. Additionally, because lock gates are submerged during operation, crack …

Demand Side Management In Smart Grid Using Big Data Analytics, Sidhant Chatterjee

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Smart Grids are the next generation electrical grid system that utilizes smart meter-ing devices and sensors to manage the grid operations. Grid management includes the prediction of load and and classification of the load patterns and consumer usage behav-iors. These predictions can be performed using machine learning methods which are often supervised. Supervised machine learning signifies that the algorithm trains the model to efficiently predict decisions based on the previously available data.

Smart grids are employed with numerous smart meters that send user statistics to a central server. The data can be accumulated and processed using data mining and machine …

A Design Methodology For Continuous Fiber Additive Manufacturing Using Advanced Computer Aided Engineering Techniques, Nicholas Venter

Mechanical and Aerospace Engineering Theses - Archive

A design methodology for Continuous Carbon Fiber Additive Manufacturing (CCFAM) developed using Computer Aided Engineering (CAE) techniques takes advantage of both the mechanical strength of composite materials and the Fused Filament Fabrication (FFF) method. By performing topology optimization and Finite Element Analysis (FEA) on a load-bearing part, engineers can design much lighter optimized parts that are just as strong as those produced using FFF. This weight reduction is achieved by relying on the mechanical strength of continuous carbon fibers printed alongside a traditional thermoplastic matrix. The FFF additive manufacturing method enables the production of complex shapes, which can match the …

Effect Of Underfill Material & Gap Height On Reliability Of Low-K Large-Die Flip Chip Package Under Thermal Loading, Paul Crisanth

Mechanical and Aerospace Engineering Theses - Archive

The reliability assessment of package assembly is important to predict the performance of any microelectronic devices. Formation of fatigue cracks at the interface between the solder joint and component is the common failure occurring in widely used microelectronic devices. Lead-free solders and advanced silicon process nodes with the low-k dielectrics flip chip package are used and are facing significant reliability challenges. The mismatch of coefficient of thermal expansion (CTE) between the chip and substrate affect solder joint reliability. The underfill encapsulant packaging is widely used to improve chip device reliability. In this paper, we are studying the effect of different …

Performance Metrics For Frequency Selective Surface-Based Sensors, Mahboobeh Mahmoodi, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

A frequency selective surface (FSS) is a periodic array of conductive elements (located on a dielectric substrate) that has a specific transmission or reflection response when illuminated with electromagnetic energy. Since the FSS response is sensitive to changes in substrate properties (permittivity, loss tangent, and thickness) as well as element geometry, FSS-based sensors have strong potential as a wireless sensing solution. To this end, this paper proposes three performance metrics (resonant frequency, resonant depth, and quality factor) to quantify the effect of substrate properties on sensor performance. These metrics are applied to a patch- A nd loop-based FSS sensor. The …

Finite Element Analysis Of Tibiofemoral Contact Mechanics, Erika Fojtik

Masters Theses

The effects of lateral meniscus posterior root avulsions (LMPRA) have been studied in combination with meniscofemoral ligament (MFL) deficiencies. The purpose of this study is to validate a set of biomechanical finite element analyses against previously reported experimental results to predict the contact area and peak contact pressure in the lateral tibiofemoral compartment of the knee during lateral meniscal root avulsions in combination with MFL deficiencies. Patient specific MRI data was used to develop finite element models for three distinct testing conditions: 1) intact, 2) lateral meniscus posterior root avulsion, and 3) lateral meniscus posterior root avulsion with deficient meniscofemoral …

Enhancing Intersection Safety For The Blind And Visually Impaired (Bvi) Pedestrian Using Device-To-Infrastructure Communication, Mohammad Sayyah Al-Akash

Masters Theses

Visually impaired pedestrians have limited mobility options, where they rely heavily on walking and transit for their transportation needs. One of the major issues facing these pedestrians is intersection crossing. Accessible Pedestrian Signals (APS), as a means of helping their intersection crossings, were introduced in the United States as early as 1920 but were not included in the Manual on Uniform Traffic Control Device (MUTCD) until 2000. The most recent type of APS is the beaconing APS which has shown improvements in road crossing abilities of blind pedestrians though it has many downsides to it. This study developed a cane …

The Temporal Expression Of Adipokines During Spinal Fusion, Sohrab Virk, Alicia L. Bertone, Hayam Hamaz Hussein, Jeffrey M. Toth, Mari Kaido, Safdar Khan

Biomedical Engineering Faculty Research and Publications

Background Context

Adipokines are secreted by white adipose tissue and have been associated with fracture healing. Our goal was to report the temporal expression of adipokines during spinal fusion in an established rabbit model.

Purpose

Our goal was to report the temporal expression of adipokines during spinal fusion in an established rabbit model.

Study Design

The study design included a laboratory animal model.

Methods

New Zealand white rabbits were assigned to either sham surgery (n=2), unilateral posterior spinal fusion (n=14), or bilateral posterior spinal fusion (n=14). Rabbits were euthanized 1–6 and 10 weeks out from surgery. Fusion was evaluated by …

An Innovative Fuzzy Backstepping Sliding Mode Controller For A Tri-Rotor Unmanned Aerial Vehicle, Shiqian Wang, Jingjuan Zhang, Qian Zhang, Chaoying Pei

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The dynamical model of a Tri-Rotor Unmanned Aerial Vehicle (UAV) is presented in this paper. The Tri-Rotor has three rotors with two fixed-pitch propellers and a tiltable propeller to control the yaw displacement. The model is obtained via the Newton–Euler approach and a nonlinear control strategy called fuzzy backstepping sliding mode control is proposed for the attitude stabilization and altitude tracking of the vehicle. The designed controller consists of a backstepping sliding mode controller and a fuzzy logic controller. For the problem of determining the backstepping sliding mode control coefficients, an optimization method of gradient descent algorithm has been used. …

Optical Flow Method For Blood Flow Velocimetry Based On Digital X-Ray Subtraction Angiography: A Brief Review, Zifeng Yang

Mechanical and Materials Engineering Faculty Publications

Detailed blood flow information has been recognized as the key information for diagnosis of vascular diseases, such as vascular stenosis and aneurysms. Optical flow method (OFM) is an emergent technique as a tool to analyze the digital x-ray subtraction angiographic images of blood vessels to obtain the detailed blood flow distribution in vascular systems. A brief review isconstructed to discuss the status, applicability, accuracy and future direction of the optical flow technique in the physical study of vascular flow.

Flexible Custom Electric Skateboard, Caleb Adam Kelsay

Electrical Engineering

At Cal Poly traveling long distances only accessible by foot such as across campus or from the car park to class can be tiring and time-consuming. While not physically demanding, the trek consumes time in our tight college life schedule. To improve our time efficiency this project provides a relatively lightweight, powered solution to quickly and effectively travel long distances while maintaining full control and safety even on hills, a current limitation of traditional skateboards.

This electric skateboard includes the battery capacity to travel all around campus on a single charge with a compact and flexible skateboard design that provides …

Analyzing The Fundamental Aspects And Developing A Forecasting Model To Enhance The Student Admission And Enrollment System Of Msom Program, Sultanul Nahian Hasnat

Graduate Theses and Dissertations

A forecasting model, associated with predictive analysis, is an elementary requirement for academic leaders to plan course requirements. The M.S. in Operations Management (MSOM) program at the University of Arkansas desires to understand future student enrollment more accurately. The available literature shows that there is an absence of forecasting models based on quantitative, qualitative and predictive analysis. This study develops a combined forecasting model focusing on three admission stages. The research uses simple regression, Delphi analysis, Analysis of Variance (ANOVA), and classification tree system to develop the models. It predicts that 272, 173, and 136 new students will apply, matriculate …

Heterogenization Of Complexes With Redox Active Ligands For Hydrogen Evolution Reaction., Wuyu Zhang

Electronic Theses and Dissertations

Hydrogen fuel is a promising future energy carrier with many applications. Thermodynamically, 1.23 V is needed for the water electrolysis, which is a clean method to generate hydrogen gas. In practice excess potential is required, which is called overpotential, due to kinetic barriers. Catalysts to reduce the overpotential for the hydrogen evolution reaction (HER) include many homogeneous catalysts and heterogeneous catalysts. Heterogenization of homogeneous catalysts on electrode surfaces is an ideal way to study a catalyst by combining homogeneous and heterogeneous study together. In this dissertation, several characterization techniques have been employed, include cyclic voltammetry, linear sweep voltammetry, electrochemical impedance …

Design, Analysis, And Application Of A Cellular Material/Structure Model For Metal Based Additive Manufacturing Process., Shanshan Zhang

Electronic Theses and Dissertations

Powder bed fusion additive manufacturing (PBF-AM) has been broadly utilized to fabricate lightweight cellular structures, which have promising potentials in many engineering applications such as biomedical prosthesis, aerospace, and architectural structures due to their high performance-to-weight ratios and unique property tailorabilities. To date, there is still a lack of adequate understanding of how the cellular materials are influenced by both the geometry designs and process parameters, which significantly hinders the effective design of cellular structures fabricated by PBF-AM for critical applications. This study aims to demonstrate a cellular structure design methodology that integrates geometrical design and process-material property designs. Utilizing …

Fused Filament Fabrication 3d Printing Using Low-Melting Alloys., Nirupama Warrier

Electronic Theses and Dissertations

Fused Filament Fabrication (FFF) 3D printing technology has been a popular method of creating prototypes using plastics in the timeliest and most affordable manner for electronic, automotive, and biomedical applications. 3D printing of metals and alloys using FFF technology could provide low-cost alternatives and solutions to the Laser-Powder Bed Fusion Process (L-PBF) and Binder Jetting processes (BJ). In current work, low melting alloys have been used as a starting material and evaluated for FFF 3D printing using two methodologies. In the first methodology, Sn60Bi40 alloy in the form of wire was used as the feedstock for FFF extrusion and process …

A Framework For Clustering And Adaptive Topic Tracking On Evolving Text And Social Media Data Streams., Gopi Chand Nutakki

Electronic Theses and Dissertations

Recent advances and widespread usage of online web services and social media platforms, coupled with ubiquitous low cost devices, mobile technologies, and increasing capacity of lower cost storage, has led to a proliferation of Big data, ranging from, news, e-commerce clickstreams, and online business transactions to continuous event logs and social media expressions. These large amounts of online data, often referred to as data streams, because they get generated at extremely high throughputs or velocity, can make conventional and classical data analytics methodologies obsolete. For these reasons, the issues of management and analysis of data streams have been researched extensively …

Material Properties Design Using Simulations And Experiments For Powder Injection Molding Of Lead Zirconate Titanate (Pzt)., Bhushan Pramod Bandiwadekar

Electronic Theses and Dissertations

Powder injection molding (PIM) process simulations can be performed to minimize the number of injection molding experiments by estimating material properties necessary for PIM simulations. In current work, lead zirconate titanate (PZT) powder-polymer binder feedstock was compounded for 45 vol. % and 52 vol. % solids loading. PIM experiments on designed micro-pillar array geometry were performed using 52 vol. % PZT. Using PIM experiments results as basis, PIM simulations were performed on designed micro-pillar array geometries to understand the effectiveness of PIM simulations with the use of estimated feedstock properties in predicting molding behavior that have micro-features. Additionally, PIM simulations …

Queue Stability Analysis In Network Coded Wireless Multicast., Nadieh Mohamadi-Moghadam

Electronic Theses and Dissertations

In this dissertation queue stability in wireless multicast networks with packet erasure channels is studied. Our focus is on optimizing packet scheduling so as to maximize throughput. Specifically, new queuing strategies consisting of several sub-queues are introduced, where all newly arrived packets are first stored in the main sub-queue on a first-come-first-served basis. Using the receiver feedback, the transmitter combines packets from different sub-queues for transmission. Our objective is to maximize the input rate under the queue stability constraints. Two packet scheduling and encoding algorithms have been developed. First, the optimization problem is formulated as a linear programming (LP) problem, …

Control Of Power Electronic Interfaces In Distributed Generation., Mohammad Mohebbi

Electronic Theses and Dissertations

Renewable energy has gained popularity as an alternative resource for electric power generation. As such, Distributed Generation (DG) is expected to open new horizons to electric power generation. Most renewable energy sources cannot be connected to the load directly. Integration of the renewable energy sources with the load has brought new challenges in terms of the system’s stability, voltage regulation and power quality issues. For example, the output power, voltage and frequency of an example wind turbine depend on the wind speed, which fluctuate over time and cannot be forecasted accurately. At the same time, the nonlinearity of residential electrical …

Artificial Olfactory System For Multi-Component Analysis Of Gas Mixtures., Alexander Aleksandrovich Larin

Electronic Theses and Dissertations

Gas analysis is an important part of our world and gas sensing technology is becoming more essential for various aspects of our life. A novel approach for gas mixture analysis by using portable gas chromatography in combination with an array of highly integrated and selective metal oxide (MOX) sensors has been studied. We developed a system with small size (7 x 13 x 16 inches), low power consumption (~10 W) and absence of special carrier gases designed for portable field analysis (assuming apriori calibration). Low ppb and even sub-ppb level of detection for some VOCs was achieved during the analysis …

Testing And Modeling Of The Thixotropic Behavior Of Cementitious Materials., Bashir Hasanzadeh

Electronic Theses and Dissertations

During construction, concrete goes under various operations. It is normally transported to the job site, be placed and consolidated in the formwork, etc. The easiness and quality of these operations are very much related to the intrinsic rheological properties of concrete. Therefore, a good understanding of rheological behavior of concrete under various conditions are needed. Thixotropy is an important part of rheology. The thixotropic behaviors of concrete can be good representatives of its flow behaviors on the job site. For example, the breakdown aspect of thixotropy can help to explain how its flow behavior can impact concrete pumping and its …

High Throughput Phenotyping Of Sorghum For The Study Of Growth Rate, Water Use Efficiency, And Chemical Composition, Piyush Pandey

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Plant phenotyping using digital images has increased the throughput of the trait measurement process, and it is considered to be a potential solution to the problem of the phenotyping bottleneck. In this study, RGB images were used to study relative growth rate (RGR) and water use efficiency (WUE) of a diverse panel of 300 sorghum plants of 30 genotypes, and hyperspectral images were used for chemical analysis of macronutrients and cell wall composition. Half of the plants from each genotype were subjected to drought stress, while the other half were left unstressed. Quadratic models were used to estimate the shoot …

Thermodynamic Limitations To Agricultural Productivity And Food Security: Livestock In Sub-Saharan Africa, Calvin Harman

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

By 2050, to feed a nearly tripling and more urbanized population in sub-Saharan Africa (SSA) will require significant increases in crop productivity throughout the region’s agricultural systems, if a greater reliance on imports is to be avoided. Increases in crop yields to maximum potential productivity (closure of crop yield gaps) can produce more calories and protein, but may be insufficient to sustain the burgeoning human population according to recent analysis (van Ittersum et al., 2016). In this thesis, alternative management options (i.e. crop allocation and crop substitutions) are found to increase total energy productivity and the thermodynamic efficiency of food …

Cultivation Of Chlorella Sorokiniana Using Beef Feedlot Runoff Holding Pond Effluent, Mitchell Klaus Goedeken

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

A study was conducted to test the suitability of utilizing beef feedlot runoff holding pond effluent for cultivating algae. The algae strain used, Chlorella sorokiniana, was previously identified as a potential energy feedstock for cattle. The previous research was initiated in pursuit of a goal to develop a cycle of utilizing nutrients from beef manure to cultivate algae and then utilizing dewatered algae as a feed supplement for beef cattle.

Runoff holding pond effluent samples were collected from commercial beef production operations in Nebraska during spring 2016. Equal portions of samples from each cooperating farm were composited and then aliquoted …

Use Of Long Term Weather Data And Spatially Delineated Field Attributes To Predict Water And Energy Conservation From Variable Rate Irrigation, Sahil Sharma

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The declining levels of the Ogallala aquifer calls for more judicious use of water. Studies have shown that VRI has the potential for water savings. But adoption of VRI is still very low. The major reason is lack of information on the returns from the VRI systems and its feasibility in different fields. Also, a quantification of the required reduction in prices of VRI is necessary. So, an economic return analysis of VRI strategies was done to compare it to uniform irrigation management (UIM) using a water balance model based on long term weather data and field properties for a …