Engineering Commons^™

Data Analysis Of Nebraska Pavements Containing Rap, Abdullah Azzam, Yong-Rak Kim, Mohammad Rahmani, Jiong Hu

Nebraska Department of Transportation: Research Reports

Nebraska has used reclaimed asphalt pavement (RAP) materials (in a range of 20-50%) over more than 10 years in pavement construction. Despite the immediate economic and environmental benefits it has been reported that incorporating RAP may reduce pavement durability and crack resistance. This study used NDOT’s database to investigate the effect of RAP amount on the overall behavior of pavement performance. Toward that end, we collected data of pavement performance, mixture design, traffic, and environment of a total 254 pavement projects constructed between 2009 and 2012. Using the data, several analyses (such as descriptive, inferential, and life cycle cost) were …

Condition Rating Prediction Using An Interactive Deterioration Model Development Package, Minwoo Chang, Mitchell S. Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper presents an advanced method to determine explanatory variables required for developing deterioration models without the interference of human bias. Although a stationary set of explanatory variables is ideal for long-term monitoring and asset management, the penalty regression results vary annually due to the innate bias in the inspection data. In this study, weighting factors were introduced to consider the inspection data collected for several years, and the most stationary set was identified. To manage the substantial amount of inspection data effectively, we proposed a software package referred to as the Deterioration Model Development Package (DMDP). The objective of …

Visualization Of Real-Time Displacement Time History Superimposed With Dynamic Experiments Using Wireless Smart Sensors And Augmented Reality, Marlon Frank Agüero Injante

Civil Engineering ETDs

Wireless Smart Sensor (WSS) process field data and inform structural field engineers and owners about the infrastructure health, condition, and safety. Engineers acquire the data and investigate changes on displacements under loads to make informed choices and prioritize decisions concerning maintenance, required repairs, and infrastructure replacements. However, reliable data collection and access to displacement information in the field in real-time under loads remains a challenge. The displacement data provided by the WSS in the field undergoes additional processing, and it is seen at a different location, at the decision-making headquarters. If inspectors were able to observe structural displacements in real-time …

Root Cause Analysis And Classification Of Single Point Failures In Designs Applying Triple Modular Redundancy In Sram Fpgas, James D. Swift

Theses and Dissertations

Radiation effects encountered in space or aviation environments can affect the configuration bits in Field Programmable Gate Arrays (FPGA) causing errors in FPGA output. One method of increasing FPGA reliability in radiation environments includes adding redundant logic to mask errors and allow time for repair. Despite the redundancy added with triple modular redundancy (TMR) and configuration scrubbing there exist some configuration bits that individually affect multiple TMR domains causing errors in FPGA output. A new tool called DeBit is introduced that identifies hardware resources associated with a single bit failure. This tool identifies a novel failure mode involving global routing …

Use Of Food Waste Activated Carbons For Wastewater Treatment, Abigale Monasterial

Honors Scholar Theses

Activated carbons are often used to remove phenol from wastewater. However, they are usually derived from expendable resources, such as coal and have high regeneration costs. In this work, the adsorption of phenol on activated carbon derived from food waste was studied to understand its kinetics, determine its maximum adsorption capacity, and compare it to commercial activated carbons. Adsorption experiments were performed at 298 K for 48 hours at various pHs and initial phenol concentrations. The adsorption data was then fit to the pseudo-first order, pseudo-second order, and intraparticle diffusion models to understand the kinetics and to the Langmuir and …

Optimal Order Assignment With Minimum Wage Consideration (Ooamwc), Hakem Alazmi

Master of Science in Computer Science Theses

While the application of crowdsourcing has increased over the years, the technology experiences various issues during implementation. Examples of some of the issues that affect crowdsourcing include task assignment, profit maximizations, as well as time window issues. In some instances addressing some of the issues results in the other issues being overlooked. An example is when assigning tasks to workers, the profits of the workers might not be considered and this ends up affecting the profit maximization aspect. Various algorithms have been proposed to address the task assignment, profit maximizations, and time window issues. However, these algorithms address the issues …

Experimental And Modeling Of Biomass Char Gasification, Ruochen Wu

Theses and Dissertations

This investigation provides a comprehensive experimental dataset and kinetic model for biomass gasification, over a wide temperature range (1150-1350 °Ï¹) in CO2, H2O and the combination of these two reactant gases over the mole fraction ranges of 0 to 0.5 for H2O and 0 to 0.9 for CO2. The data come from a unique experimental facility that tracks continuous mass loss rates for poplar wood, corn stover and switchgrass over the size range of 6-12.5 mm. In addition, the data include char size, shape, surface and internal temperature and discrete measurements of porosity, total surface area, pore size distribution and …

Flow Patterns, Velocity Distributions And Mixing Time In Stirred Tank Reactor Under A Range Of Operating Conditions, Nor Haslina Abdullah

Student Works (2020-2029)

The present work employed a two-dimensional Particle Imaging Velocimetry (PIV) technique to determine the flow patterns and velocity distributions of a down-pumping pitched-blade turbine (4PB) and a Rushton turbine (RT) in a flat-bottom fully baffled stirred vessel (T=0.155m) using distilled water and glycerin as liquids. Fluid velocities increased as the impeller speed increased from 50rpm to 300rpm for both fluids and the RT impeller reached a maximum value of velocity of 1.42m/s at the blade tip. The 4PB had higher velocity compared to RT in glycerin, but RT had higher velocity than 4PB in distilled water. In water, radial flow …

The Impact Of Grinding Time On Properties Of Cement Mortar Incorporated High Volume Waste Paper Sludge Ash, Ali A. Shubbar, Monower Sadique, Mohammed S. Nasr, Zainab S. Al-Khafaji, Khalid S. Hashim

Karbala International Journal of Modern Science

Cement is considered a base material in preparing blending mixtures that applying in various projects in the civil engineering field. Nevertheless, the cement production process cause indubitable negative environmental influences such as emitting CO₂. The production of cement produces around 7% of the global CO₂ emissions. Thus, searching for alternate binders in building processes to minimise or substitute cement has been one of the social problems. A by-product or waste products are among the potential alternatives to the mentioned problem. The present investigation involves the consumption of paper sludge ash (PSA) waste as cement replacement to produce …

Feasibility Of Continuous Fever Monitoring Using Wearable Devices, Benjamin L. Smarr, Kirstin Aschbacher, Sarah M. Fisher, Anoushka Chowdhary, Stephan Dilchert, Karena Puldon, Adam Rao, Frederick M. Hecht, Ashley E. Mason

Publications and Research

Elevated core temperature constitutes an important biomarker for COVID-19 infection; however, no standards currently exist to monitor fever using wearable peripheral temperature sensors. Evidence that sensors could be used to develop fever monitoring capabilities would enable large-scale health-monitoring research and provide high-temporal resolution data on fever responses across heterogeneous populations. We launched the TemPredict study in March of 2020 to capture continuous physiological data, including peripheral temperature, from a commercially available wearable device during the novel coronavirus pandemic. We coupled these data with symptom reports and COVID-19 diagnosis data. Here we report findings from the first 50 subjects who reported …

Probing The Impacts Of Ultra-Low Platinum Loadings On Membrane Degradation Mechanisms, Andre J. Spears

Nanoscience and Microsystems ETDs

Membrane chemical degradation is one of many factors that can impact fuel cell durability. The fuel cell’s performance and lifetime heavily depends on the membrane and its ability to maintain chemical and mechanical integrity. In Nafion^® membranes, hydroxyl radicals are the primary cause of chemical membrane degradation as they attack the membrane’s polymer structure. Radical formation can ensue via peroxide decomposition at the cathode or gases reacting on Pt particles or contaminants like Fe (a fenton's reagent) within the membrane. As radicals attack the membrane’s polymer structure the membrane thins, and fluoride and sulfate ions are released. This consequently …

Instructional Case Studies In The Field Of Windfarm Optimization, N. Francesco Baker

Theses and Dissertations

Wind farm layout optimization is a multidisciplinary undertaking, requiring students and researchers to integrate many skillsets in order to optimize turbine placement. There is currently a lack of useful benchmarking exercises for participants in the field to compare the efficacy of their methods. This work details the construction and completion of a set of four case studies meant to satisfy this need, with the hope of providing some insight into useful layout optimization approaches. These case studies are intended to also serve as instructive introductory exercises with which newcomers researching wind energy may incrementally practice and increase their abilities.The first …

Two New Finite Element Schemes And Their Analysis For Modeling Of Wave Propagation In Graphene, Jichun Li

Mathematical Sciences Faculty Research

© 2020 The Author(s) In this paper, we investigate a system of governing equations for modeling wave propagation in graphene. Compared to our previous work (Yang et al., 2020), here we re-investigate the governing equations by eliminating two auxiliary unknowns from the original model. A totally new stability for the model is established for the first time. Since the finite element scheme proposed in Yang et al. (2020) is only first order in time, here we propose two new schemes with second order convergence in time for the simplified modeling equations. Discrete stabilities inheriting exactly the same form as the …

Blast-Induced Liquefaction And Downdrag Development On A Micropile Foundation, Cameron Mark Lusvardi

Theses and Dissertations

Frequently, deep foundations extend through potentially liquefiable soils. When liquefaction occurs in cohesionless soils surrounding a deep foundation, the skin-friction in the liquefied layer is compromised. After cyclical forces suspend and pore pressures dissipate, effective stress rebuilds and the liquefied soil consolidates. When the settlement of the soil exceeds the downward movement of the foundation, downdrag develops. To investigate the loss and redevelopment of skin-friction, strain was measured on an instrumented micropile during a blast-induced liquefaction test in Mirabello, Italy. The soil profile where the micropile was installed consisted of clay to a depth of 6m underlain by a medium …

Intelligent Networks For High Performance Computing, William Whitney Schonbein

Computer Science ETDs

There exists a resurgence of interest in `smart' network interfaces that can operate on data as it flows through a network. However, while smart capabilities have been expanding, what they can do for high-performance computing (HPC) is not well-understood. In this work, we advance our understanding of the capabilities and contributions of smart network interfaces to HPC. First, we show current offloaded message demultiplexing can mitigate (but not eliminate) overheads incurred by multithreaded communication. Second, we demonstrate current offloaded capabilities can be leveraged to provide Turing complete program execution on the interface. We elaborate with a framework for offloading arbitrary …

Bibliometric Survey On Effect Of Climate Factors On Spread Of Coronavirus (Covid-19), Seema Patil, Jay Makwana, Manish Attri

Library Philosophy and Practice (e-journal)

The new SARS-CoV-2 COVID-19 has spread quickly around the globe since it was first reported in Wuhan city of China, in December 2019 subsequent to being contracted from a zoonotic source. The main focus of this bibliometric survey is to recognize the few studies which have upheld the epidemiological hypothesis that the effect of climatic factors is playing a crucial role in the spreading of COVID-19. The analysis is done on the basis of 412 documents such as journals, articles, editorials, short surveys and some review papers. The United States contributes to the maximum number of publications followed by the …

A Logical Method For Finding Maximum Compatible Subsystems Of Systems Of Boolean Equations, Anvar Kabulov, Erkin Urunbaev, Mansur Berdimurodov

Scientific Journal of Samarkand University

The problem of finding the maximum joint subsystem of Boolean equation systems is solved. An algorithm for finding the maximum upper zero of a monotone Boolean function is proposed. An efficient procedure for calculating the values of monotone functions on sets of a - dimensional cube is investigated and developed. An algorithm for solving systems of Boolean equations based on the search for the maximum upper zero of monotone functions of the logic algebra is developed.

Сharacteristics Mineral Resource Base Of Madagascar, A. E. Vorobyev, K. A. Vorobyov, S.A. Ndriambanuna, L.E. Schesnyak

Gorniy vestnik Uzbekistana

The main characteristics of the mineral resource base of Madagascar with details of coal, iron ore, non-ferrous metals, uranium, rare metals and gold are considered. In the gold-ore mineral base of Madagascar, coastal placers are of particular potential interest. Foreign mining companies and local crafts are described. The transition to the development of coastal gold placers is proposed

Study Of The Change In The Concentration Of Metal Ions In Bacterial Oxidation Of Floto Concentrate In The Liquid Phase, K. Sanakulov, B.F. Muhiddinov, S.Sh. Sharipov, A.T. Umrzakov

Gorniy vestnik Uzbekistana

The article presents the results of a study of the qualitative and quantitative analysis of metal ions in the bacterial oxidation of flotation concentrate in the liquid phase by mass spectroscopy. Changes in the concentration of metal ions (Na, Si, K, Ca, Fe, etc.) and ions of noble metals (gold, silver) in the process of bacterial oxidation of flotation concentrate were determined and changes in their concentration in the process were substantiated

Improving The Quality Of Cathodic Precipitation Coming To The Gmz-2 Of The State Enterprise "Navoi Mmc", Adizov L.A., Sh.R. Kodirov, Tazhibaev D.Yu., Ergashev N.U.

Gorniy vestnik Uzbekistana

In this article, the object of research was the cathode precipitation of GMZ-4, obtained by electrolytic precipitation of rich gold-containing solutions after intensive leaching of gravioconcentrates. As a result of the conducted research, to improve the quality of cathode precipitation in the conditions of GMZ-2, the optimal method of nitric acid treatment was chosen. This method is implemented on an industrial scale in the shop of finished products and is used when cathode precipitation is below the required quality

Innovative Centrifugal Concentrator Bowl From Sepro Mineral Systems, Van Kleek Mark, A. Pariy, M. Grodowski

Gorniy vestnik Uzbekistana

Modern centrifugal concentrators have become standard equipment for most precious metal extraction technologies due to their simplicity, cost-effectiveness and efficiency. However, as with any other technology, there is always room for improvement. Sepro Mineral Systems, Canada's largest supplier of mineral processing equipment, has developed a new Frontier centrifugal concentrator bowl (patent pending), which will soon be installed on all Falcon gravity concentrators, and will also be able to serve as a replacement part for most Knelson concentrator models.

Schemes Of Fast Automatic Input Of The Reserve For Electricity Systems With High-Voltagemi Asynchronny Electric Motors, Kholboev G.O., Aliyor Hamidov, Ataullaev A.O., Rasulova B.I.

Gorniy vestnik Uzbekistana

The main purpose of developing a fast-acting automatic reserve inclusion system is to reduce the impact of transition processes, mechanical impacts on engines and current throws while maintaining uninterrupted power supply to the engines at a time when power is disrupted from one of the power sources and the load is switched to the second source.

Using Eye-Gaze To Evaluate Neural Attention, Shahansha Salim

Master’s Dissertations

The ability to selectively concentrate on areas of interest while ignoring the rest is termed as attention in human beings. This ability has played a key role in survival as well as information processing. Neural Attention is said to be an effort to bring similar action of selectively concentrating areas of relevance in deep neural networks. This simple yet powerful concept has attracted a lot of research in recent years, yielding breakthrough results in Natural Language Processing (NLP) problems and main stream Computer Vision problems such as Image Caption Generation, Neural Machine Translation (NMT), Visual Question Answering (VQA), Action Recognition, …

Stirling Cycle Machine Analysis, Israel Urieli

OHIO Open Faculty Textbooks

Dedicated to William T. Beale (1928 - 2016), inventor of the Free Piston Stirling Engine, Mentor and Frien.

This web resource is intended to be totally self contained learning resource for the analysis and development of computer simulation of single phase, piston/cylinder Stirling cycle machines. It includes thermodynamic, heat transfer and fluid flow friction analysis, and until 2012 it was used as resource material for an advanced course for Mechanical Engineering majors. The course structure was based on the book by I.Urieli & D.M.Berchowitz 'Stirling Cycle Engine Analysis' (Adam Hilger, 1984). The computer simulation program modules (originally written in FORTRAN) …

Towards Understanding Power Grid Resilience To Early-Time (E1) High-Altitude Electromagnetic Pulses, Rodrigo Elias Llanes

Electrical and Computer Engineering ETDs

Fast transient electromagnetic disturbances can occur in the atmosphere from natural occurrences such as lightning and solar flares as well as those from manmade events such as that associated with a nuclear bomb detonation. These radiated signals couple into the transmission lines and components within the electric power grid. This has prompted an increased interest in grid resilience to the Early-Time (E1) High-Altitude Electromagnetic Pulse (HEMP). Three activities were conducted which further grid resilience research. First, power substations in the United States were assessed to develop accurate layouts to be used in radiated transmission line coupling studies. Second, three pre-existing …

Circuit Topology Estimation In An Adaptive Protection Platform, Daniel Ruiz

Electrical and Computer Engineering ETDs

Modern electric power systems, power system protections and controls have experienced a significant change, thanks to the introduction of new technologies, such as microprocessors, GPS, communication, etc. These technologies brought an increased amount of measured-data and information flow on power grids. Adaptive protection systems have been introduced to increase the reliability, selectivity, and sensitivity of the traditional protection systems. An adaptive protection system highly relies on the communication system infrastructure to identify the latest status of power grid (e.g., circuit topology or generation level of distributed energy resources). However, when the communication links to some of the equipment are outaged …

Mesh Networking And Security Applications In Lora Ad-Hoc Networks, Derek Heeger

Electrical and Computer Engineering ETDs

The Internet of Things (IoT) has rapidly expanded into consumer and industrial applications driving the need for secure and energy efficient communications suitable for battery powered devices. Common IoT protocols developed for these applications include SigFox, Narrow-Band IoT, and Long Range (LoRa). LoRa is an energy efficient long-range communication method enabled by advanced modulation schemes. This research enables new capabilities in LoRa ad-hoc networks allowing for innovative IoT sensors that were previously infeasible due to energy constraints. This is achieved by investigating adaptive data rate (ADR) techniques, enabling reliable and secure remote firmware updates, improving LoRa authentication, and implementing a …

Cognitive Radios For Self-Aware And Spectrum-Agile Communications Over Wideband Spectrum, Mohamed A. Aref

Electrical and Computer Engineering ETDs

In this dissertation, we introduce a novel cognitive engine design for intelligent, self-aware and spectrum-agile communications. The targeted cognitive radio (CR) has sensing and learning abilities that incorporate advanced signal processing and machine/deep learning (ML/DL) techniques. It can operate over a heterogeneous wideband spectrum that is much wider than the ones proposed in the literature, most likely covering several hundreds of MHz. It has the ability to detect existing signals in the surrounding RF environment and identify their origins. Furthermore, it cognitively uses channel selection, transmit power control and interference cancellation to adapt its communications mode in response to observed …

Numerical Evaluation Of Effective Thermal Response Of Heterogeneous Materials, Kevin W. Irick

Mechanical Engineering ETDs

Heterogeneity in materials leads to increased complication of physics, at the level or scale where heterogeneity exists, making analysis and material behavior predictions more difficult. As a result of the intricate descriptions or understanding of the physics required to determine the behavior of a heterogenous material or system, practitioners frequently prefer the use of effective properties or responses. This body of work is dedicated to performing computational analyses on the thermal behavior of heterogeneous materials and evaluating the corresponding analyses using formal verification approaches. Custom finite element method code was used for solving the heat equation in a variety of …

Solar Insolation Micro-Forecasts Using Longwave Infrared Sensors And Artificial Intelligence, Anthony R. Menicucci

Mechanical Engineering ETDs

Solar Insolation Micro-Forecasts (SIMF) are used by Independent Service Operators (ISOs) and other grid operators to maintain constant and stable electrical grid frequency, voltage, power factor and waveform across their transmission infrastructure. Intermittent, thick, dense and typically cumulus clouds negatively impact the electrical grid by quickly turning on and off power production from large solar photovoltaic (PV) fields, causing grid stability problems between generation and load. Forecasting insolation values over large PV fields allows operators the chance to anticipate and proactively implement mitigation strategies like engaging spinning reserve from gas turbines, deploying generators, buying power in the spot market, and …