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2020

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Articles 1171 - 1200 of 10640

Full-Text Articles in Engineering

Engineered Geopolymer Composites (Egcs) For Sustainable Transportation Infrastructure, Gabriel Arce, Marwa Hassan, Miladin Radovic, Svetlana Sukhishvili, Ruwa Abufarsakh, Oscar Huang, Sang Zhen, Mauricio Cornejo, Haci Baykara Nov 2020

Engineered Geopolymer Composites (Egcs) For Sustainable Transportation Infrastructure, Gabriel Arce, Marwa Hassan, Miladin Radovic, Svetlana Sukhishvili, Ruwa Abufarsakh, Oscar Huang, Sang Zhen, Mauricio Cornejo, Haci Baykara

Publications

The objective of this study was to develop novel Engineered Geopolymer Composite (EGC) materials implementing locally available ingredients to produce practical and cost-effective EGCs for repair and new construction of transportation infrastructure in the region. To this end, geopolymers (GPs) were synthesized by alkali activation of metakaolin (MK) or a combination of metakaolin and fly ash (MKFA) as GP precursors. MK-GPs were activated using sodium silicate and potassium silicate solutions prepared by dissolving silica fume (SiO2) and KOH or NaOH in deionized water. MKFA-GPs replaced silica fume using fly ash and were activated using only KOH solution. GP …


Engineered Geopolymer Composites (Egcs) For Sustainable Transportation Infrastructure, Gabriel Arce, Marwa Hassan, Svetlana Sukhishvili, Ruwa Abufarsakh, Oscar Huang, Sang Zhen, Mauricio Cornejo, Haci Baykara Nov 2020

Engineered Geopolymer Composites (Egcs) For Sustainable Transportation Infrastructure, Gabriel Arce, Marwa Hassan, Svetlana Sukhishvili, Ruwa Abufarsakh, Oscar Huang, Sang Zhen, Mauricio Cornejo, Haci Baykara

Data

The objective of this study was to develop novel Engineered Geopolymer Composite (EGC) materials implementing locally available ingredients to produce practical and cost-effective EGCs for repair and new construction of transportation infrastructure in the region. To this end, geopolymers (GPs) were synthesized by alkali activation of metakaolin (MK) or a combination of metakaolin and fly ash (MKFA) as GP precursors. MK-GPs were activated using sodium silicate and potassium silicate solutions prepared by dissolving silica fume (SiO2) and KOH or NaOH in deionized water. MKFA-GPs replaced silica fume using fly ash and were activated using only KOH solution. GP …


Evaluation Of Asphalt Mixtures’ Resistance To Cement-Treated Base (Ctb) Reflective Cracking In The Laboratory, Husam Sadek, Marwa Hassan, Charles Berryman, Mohammad Hossain, Ipshit Idris Nov 2020

Evaluation Of Asphalt Mixtures’ Resistance To Cement-Treated Base (Ctb) Reflective Cracking In The Laboratory, Husam Sadek, Marwa Hassan, Charles Berryman, Mohammad Hossain, Ipshit Idris

Publications

The primary objective of this project is to propose a laboratory setup to test and evaluate an asphalt mixture layer on top of a simulated Cement-Treated Base (CTB) layer against reflective cracking. An in-depth literature review on the experimental studies that were conducted throughout the world to investigate the resistance of asphalt mixtures to reflective cracking was conducted. Texas Transportation Institute (TTI) Overlay Tester (OT) was found to be the most appropriate equipment to study thermally-induced reflective cracking in the laboratory, and thereby was selected to be modified and used to assess the performance of asphalt mixtures on top of …


Corrosion Management System Of Regional Reinforced Concrete (Rc) Bridges, Homero Castaneda, Ayman Okeil Nov 2020

Corrosion Management System Of Regional Reinforced Concrete (Rc) Bridges, Homero Castaneda, Ayman Okeil

Data

Civil infrastructure assets, including buildings, transportation networks, energy grids and networks, and water-sewer systems, are critical functional components of day-to-day life activity in a modern society. The durability and reliability of these civil infrastructures are largely affected by corrosion-induced structural deterioration. In addition to continual use and increasing traffic demands, natural environmental conditions set degradation due to corrosion damage as a critical condition to durable and reliable infrastructures. Therefore, in order to improve the durability of the bridge infrastructures affected by corrosion in the most efficient manor, we propose a procedure/methodology to manage integrity of corroding RC bridges which is …


Enhancing The Performance Of Asphalt Mixtures Containing High Rap Content With The Use Of Different Wma Technologies, Husam Sadek, Marwa Hassan, Charles Berryman, Mohammad Hossain, Farah Zaremotekhases Nov 2020

Enhancing The Performance Of Asphalt Mixtures Containing High Rap Content With The Use Of Different Wma Technologies, Husam Sadek, Marwa Hassan, Charles Berryman, Mohammad Hossain, Farah Zaremotekhases

Data

The production of Warm-mix asphalt mixtures in conjunction with reclaimed asphalt pavement (RAP) has received considerable interest in recent years for economic and environmental reasons. The primary objective of this project is to enhance the performance of asphalt mixtures containing RAP in Region 6 using different WMA technologies. In this project, the effect of utilizing 0%, 25%, and 35% RAP contents on the performance of different WMA mixtures against rutting, moisture damage, and fatigue cracking are evaluated. The effects of the WMA technologies on the rutting performance of the asphalt mixtures and recovered binders were investigated using loaded wheel tracker …


Bridge Deck Inspection Using Small Unmanned Aircraft Systems Based Airborne Imaging Techniques, Su Zhang, Shirley Baros, Susan Bogus Nov 2020

Bridge Deck Inspection Using Small Unmanned Aircraft Systems Based Airborne Imaging Techniques, Su Zhang, Shirley Baros, Susan Bogus

Data

As one of critical components of a transportation infrastructure system, bridges are very important to a country’s economy because they provide passage over physical obstacles to substantially reduce travel time and travel cost. Similar to other types of transportation infrastructure, bridges deteriorate over time. Therefore, bridges should be routinely inspected to ensure their serviceability, capacity, and safety under current traffic. Subsequently, transportation agencies at all levels (e.g., federal, state, local, and tribal) dedicate large amounts of time and money to routinely monitor and inspect bridge conditions as part of their infrastructure asset management programs. These transportation agencies use the collected …


Development Of A Low Power, Low Cost Rural Railway Intersection Smart Detection And Warning System, Sara Ahmed, Samer Dessouky, Raymond Downing Nov 2020

Development Of A Low Power, Low Cost Rural Railway Intersection Smart Detection And Warning System, Sara Ahmed, Samer Dessouky, Raymond Downing

Data

This project explores a different approach to provide preemptive warning for train detection at grade-crossings to increase safety and reduce motor vehicle congestion. The development of a novel, low cost, low power, and off rail right-of-way (ROW) detection and warning system will be presented. A background of track circuits, which is the rail industries standard for train detection, will also be provided to highlight the benefits and challenges of the rail industry installing a system at every grade-crossings that lack any type of active warning. The benefits of using thermal imaging instead of traditional video for computer vision will also …


Bridge Deck Inspection Using Small Unmanned Aircraft Systems Based Airborne Imaging Techniques, Su Zhang, Shirley Baros, Susan Bogus Nov 2020

Bridge Deck Inspection Using Small Unmanned Aircraft Systems Based Airborne Imaging Techniques, Su Zhang, Shirley Baros, Susan Bogus

Publications

As one of critical components of a transportation infrastructure system, bridges are very important to a country’s economy because they provide passage over physical obstacles to substantially reduce travel time and travel cost. Similar to other types of transportation infrastructure, bridges deteriorate over time. Therefore, bridges should be routinely inspected to ensure their serviceability, capacity, and safety under current traffic. Subsequently, transportation agencies at all levels (e.g., federal, state, local, and tribal) dedicate large amounts of time and money to routinely monitor and inspect bridge conditions as part of their infrastructure asset management programs. These transportation agencies use the collected …


Distributed Energy Resource Aggregation Using Customer-Owned Equipment: A Review Of Literature And Standards, Manasseh Obi, Tylor Slay, Robert B. Bass Nov 2020

Distributed Energy Resource Aggregation Using Customer-Owned Equipment: A Review Of Literature And Standards, Manasseh Obi, Tylor Slay, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

Large-scale deployment of renewable energy resources, both utility-scale and distributed, create reliability concerns for electrical power system operators. The weather-dependent, non-dispatchable nature of renewable resources decreases the ability of operators to match supply with demand. Concurrently, distributed energy resources, defined as small-scale loads, generation sources, and storage systems, are becoming ubiquitous within modern electrical systems. This literature review presents the grid services that utilities use to alleviate power systems reliability concerns, particularly those caused by renewable resources, and how aggregations of residential-scale distributed energy resources can be used to provide these services.

By aggregating distributed energy resources en masse to …


The Effect Of Carbonate Rock Wettability On The Performance Of Low Salinity Water Flooding: An Experimental Approach, Hildah Nantongo Nov 2020

The Effect Of Carbonate Rock Wettability On The Performance Of Low Salinity Water Flooding: An Experimental Approach, Hildah Nantongo

Chemical and Petroleum Engineering Theses

The performance of low salinity waterflooding (LSWF) in different wettability environment is still unclear for the oil industry. The concessions among researchers are that low salinity does not work in water-wet carbonate oil reservoirs. In this project carbonate core flooding experiments on cores with different wettability’s conditions, including water-wet, oil-wet, and intermediate wettability were performed at reservoir conditions of pressure and temperature. Seawater was selected as a base water and its concentration & composition were modified through dilution and/or spiking with sulfate. The base water was diluted with water 10 and 50 times and spiked with sulfate to 2 and …


Detection Of Corrosion-Indicating Oxidation Product Colors In Steel Bridges Under Varying Illuminations, Shadows, And Wetting Conditions, Dayakar L. Naik, Hizb Ullah Sajid, Ravi Kiran, Genda Chen Nov 2020

Detection Of Corrosion-Indicating Oxidation Product Colors In Steel Bridges Under Varying Illuminations, Shadows, And Wetting Conditions, Dayakar L. Naik, Hizb Ullah Sajid, Ravi Kiran, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Early detection of corrosion in steel bridges is essential for strategizing the mitigation of further corrosion damage. Although various image-based approaches are available in the literature for corrosion detection, most of these approaches are tested on images acquired under uniform natural daylight illuminations i.e., inherent variations in the ambient lighting conditions are ignored. Owing to the fact that varying natural daylight illuminations, shadows, water wetting, and oil wetting are unavoidable in real-world scenarios, it is important to devise a robust technique for corrosion identification. In the current study, four different color spaces namely ‘RGB’, ‘rgb’, ‘HSV’ and ‘CIE La*b*’ along …


Standards For Technological And Engineering Literacy: Addressing Trends And Issues Facing Technology And Engineering Education, Johnny J. Moye, Philip A. Reed Nov 2020

Standards For Technological And Engineering Literacy: Addressing Trends And Issues Facing Technology And Engineering Education, Johnny J. Moye, Philip A. Reed

STEMPS Faculty Publications

The article offers information on addressing trends and issues facing technology and engineering education. It mentions future challenges, students need to "have a broad conceptual understanding of technology and its place in society, enabling them to be active participants in the technological world and careful creators and users of technology.


Comparative Transport Of Legionella And E. Coli Through Saturated Porous Media In A Two-Dimensional Tank, Indrayudh Mondal, Jazlyn Acosta, Absar Alum, Brooke K. Mayer, Paul Dahlen, Morteza Abbaszadegan Nov 2020

Comparative Transport Of Legionella And E. Coli Through Saturated Porous Media In A Two-Dimensional Tank, Indrayudh Mondal, Jazlyn Acosta, Absar Alum, Brooke K. Mayer, Paul Dahlen, Morteza Abbaszadegan

Civil and Environmental Engineering Faculty Research and Publications

This study investigated bacterial transport in a two-dimensional (2-D) tank to evaluate the bacterial behavior of Legionella pneumophila as compared to Escherichia coli under saturated flow to simulate aquifer conditions. The experiments were performed in a 2-D tank packed with 3700 in3 (60,632 cm3) of commercially available bagged play sand under saturated conditions. The tank was disinfected by backwashing with 10% chlorine solution and subsequently neutralized by backwashing with tap water containing sodium thiosulphate (Na2S2O3) to ensure no chlorine residual. Bacterial transport was measured using samples collected from ports located at …


Ofdm Simulation, Joseph W. Bednar Nov 2020

Ofdm Simulation, Joseph W. Bednar

Electrical Engineering

The project objective is to provide a tool that will allow the user to simulate an adaptive OFDM (Orthogonal Frequency-Division Multiplexing) communication system in the presence of various types of interference and noise. The open-source code allows students and engineers to adjust the modulation, threshold settings, and distortion effects in the channel while observing the output bit error rate. The results the simulation provides will aid researchers in attempting to characterize the interference of OFDM based systems and their effectiveness in the presence of noise.


Engine Light Repair Shop Evaluation For A Brazilian Airline, Gustavo Henrique Melhado Trevilatto, Marcelo Miranda, Leila Halawi Nov 2020

Engine Light Repair Shop Evaluation For A Brazilian Airline, Gustavo Henrique Melhado Trevilatto, Marcelo Miranda, Leila Halawi

Publications

The maintenance cost of a commercial aircraft comprises airframe, components, and engines. The most expensive of them are engines, which may represent up to 60% of an aircraft cost, and therefore will have a significant impact on any airline finance. As a result, engine fleet maintenance management is crucial for any airline sustainability. Apart from heavy maintenance where life-limited parts are replaced and its performance restored, aircraft engines are often required to come off wing for light repair due to operational issues like foreign object damage, high oil consumption, and vibration issues. In other cases, even though being operational, engines …


Effect Of Cold Work Expansion On The Fatigue Life Of Pre-Cracked Al 2024-T3, Christopher Leirer Nov 2020

Effect Of Cold Work Expansion On The Fatigue Life Of Pre-Cracked Al 2024-T3, Christopher Leirer

Doctoral Dissertations and Master's Theses

No abstract provided.


Geomagnetic Aided Dead-Reckoning Navigation, Andrei Cuenca Nov 2020

Geomagnetic Aided Dead-Reckoning Navigation, Andrei Cuenca

Doctoral Dissertations and Master's Theses

The dependence of modern navigation methods on global positioning systems has led to developing alternative algorithms for localization, capable of providing reliable and robust estimations. Global position system is commonly used in a vast majority of the world’s devices, and it can supply real time position and velocity information. However, its accuracy can be compromised by external operational effects such as signal availability, cyber-attacks or weather conditions. This thesis investigates an alternative approach to enhance navigation in GPS-denied environments. Particularly, it develops an integrated navigation architecture based on geomagnetic referencing models capable of dead reckoning at GPS denied intervals. A …


An Exploratory Study Of General Aviation Visual To Instrument Meteorological Condition Contextual Factors, James Harry Hartman Iii Nov 2020

An Exploratory Study Of General Aviation Visual To Instrument Meteorological Condition Contextual Factors, James Harry Hartman Iii

Doctoral Dissertations and Master's Theses

The purpose of this dissertation was to bridge the existing literature gap of outdated contextual factor (CF) research through examination and determination of current General Aviation (GA) Title 14 Code of Federal Regulations (CFR) Part 91 visual flight rules (VFR)-into-instrument meteorological condition (IMC) contextual factors. Contextual factors are a multifaceted arrangement of pertinent events or occurrences contributing to pilot accidents in weather-related decision-making errors. A total of 46 contextual factors were identified and examined from the reviewed research literature. The study examined and determined the presence of the 46 contextual factors, frequencies, and manifestations in the GA VFR-into-IMC Aviation Accident …


Final Design Review Report: The Underdogs, Parker Johnson, Jack Montgomery, Katherine Thomas Nov 2020

Final Design Review Report: The Underdogs, Parker Johnson, Jack Montgomery, Katherine Thomas

Mechanical Engineering

Aspen is a three-legged dog with mobility issues from Berkeley, California. She was hit by a car and her rear left leg was amputated at the hip. Robin Swanson, Aspen's owner, and her friend, Audrey Beil, are the sponsors for this project. Jack Montgomery, Katherine Thomas, and Parker Johnson, “The Underdogs”, are tasked with helping Aspen regain some of her mobility and the ability to go on walks. Research was done into the problem by talking with the sponsors and looking into existing products, designs, and patents. This document, the Final Design Review Report, outlines the background information, problem specification, …


Portable Wind Turbine Blade Leading Edge Erosion Test, Joe Blakewell, Tim Holt, Kevin Vartan Nov 2020

Portable Wind Turbine Blade Leading Edge Erosion Test, Joe Blakewell, Tim Holt, Kevin Vartan

Mechanical Engineering

Turbine Technology Partners, LLC (TTP) is a company located in Santa Barbara, California that provides expert independent engineering (IE) consulting services to the wind energy industry - supporting its goal of generating cost effective and reliable carbon-free renewal energy for the world. TTP customers include some of the largest wind turbine original equipment manufacturers (OEMs), wind turbine power plant developers, and wind turbine owner/operators. One of the biggest problems challenging the wind energy industry currently is the power loss that results from the leading edge (LE) erosion of wind turbine blades. The purpose of our senior design project is to …


2 Degree Of Freedom Robotic Leg, Oded Tzori, Henry Terrell, Adan Martinez Nov 2020

2 Degree Of Freedom Robotic Leg, Oded Tzori, Henry Terrell, Adan Martinez

Mechanical Engineering

Professor Xing, an assistant professor at Cal Poly, proposed the 2 DOF Robotic Leg project for this quarter’s senior project class. The project is to build a robotic leg attached at the hip to a stand, which will be used as a teaching tool and eventually help develop Cal Poly’s very own robotic quadruped. Since this project has multiple uses after its completion, there are multiple customers that it must perform well for: the Cal Poly Mechanical Engineering (ME) Department, the ME Lab instructors, and the students. The Scope of Work (Sections 2 & 3) is composed of 2 main …


Bolted Flanged Assembly Test Stand, Mark Christian Damasco Sunga, Paulina Mercedez Delgado, Philip John Coleman Nov 2020

Bolted Flanged Assembly Test Stand, Mark Christian Damasco Sunga, Paulina Mercedez Delgado, Philip John Coleman

Mechanical Engineering

The following Final Design Report (FDR) is the last formal documentation for the senior design project. The project was carried out by three senior mechanical engineering students at California Polytechnic State University, San Luis Obispo for Phillips 66. The project proposed was to design a test stand and implement a procedure which will evaluate craftsmen’s abilities to assemble a bolted flanged joint assembly. The goal was to create a fully functional test setup that can be duplicated and utilized throughout Phillips 66’s refineries. This document details the design process that was completed over the course of three quarters, including concept …


Adaptable Classroom And Workspace Table, Emily Richter, Aaron Mccallister, Jett Bolusan Nov 2020

Adaptable Classroom And Workspace Table, Emily Richter, Aaron Mccallister, Jett Bolusan

Mechanical Engineering

Mr. Michael Brennan, entrepreneur and founder of Co-Act Furniture, presented the problem of a classroom and workspace table that can be quickly, easily, and safely reconfigured to accommodate different types of collaboration and learning within a limited space. Current classroom and workspace furniture lacks modularity, which limits the usability of the space. Different groups use the same room to learn in different ways; adjustable furniture would benefit their learning and productivity. Mr. Brennan has developed several prototype tables with varying features, including adjustable angle, height, and tabletop surface area. Our team, composed of three mechanical engineering students, has a project …


Deep-Sea Water Collector, Chandler Jones, Jenny Verheul, Michael Di Giorgio Nov 2020

Deep-Sea Water Collector, Chandler Jones, Jenny Verheul, Michael Di Giorgio

Mechanical Engineering

Properties such as nutrients, DNA, pH levels, and primary productivity are difficult to measure onboard an Underwater Remotely Operated Vehicle (UROV) as mobile submarine sensors are highly expensive and conventional water capture devices are too large to be equipped. However, these properties provide an integral view into our oceans, the species that inhabit them, and our influence on the environment. Collected samples of seawater taken back to labs allow researchers to see a clearer picture of ecosystems’ inhabitants and lifecycle with the analysis of Environmental DNA (eDNA) among many other properties. The scope of this project is to design a …


Modular Attachment System For Tactical Robot, Michelle K. Chandler, Jacob A. Nelson, Adam V. Ivelia, Quang Truong Nov 2020

Modular Attachment System For Tactical Robot, Michelle K. Chandler, Jacob A. Nelson, Adam V. Ivelia, Quang Truong

Mechanical Engineering

The goals of this report are to clearly define the problem and the scope of this project, present information regarding background design research, explain the process taken to reach the final design, go over the part procurement and manufacturing process, outline the assembly steps, and verify the design against the criteria through testing. The problem and scope of the project were defined using the constraints provided by the project sponsor, Blueline robotics. Blueline needs a modular attachment system for their tactical robot. The completed background research contains existing robot solutions that deal with similar tasks. Many of these existing robots …


Extending The Functional Subnetwork Approach To A Generalized Linear Integrate-And-Fire Neuron Model, Nicholas Szczecinski, Roger Quinn, Alexander J. Hunt Nov 2020

Extending The Functional Subnetwork Approach To A Generalized Linear Integrate-And-Fire Neuron Model, Nicholas Szczecinski, Roger Quinn, Alexander J. Hunt

Mechanical and Materials Engineering Faculty Publications and Presentations

Engineering neural networks to perform specific tasks often represents a monumental challenge in determining network architecture and parameter values. In this work, we extend our previously-developed method for tuning networks of non-spiking neurons, the “Functional subnetwork approach” (FSA), to the tuning of networks composed of spiking neurons. This extension enables the direct assembly and tuning of networks of spiking neurons and synapses based on the network’s intended function, without the use of global optimization ormachine learning. To extend the FSA, we show that the dynamics of a generalized linear integrate and fire (GLIF) neuronmodel have fundamental similarities to those of …


Characterization And Manipulation Of Carbon Precursor Species During Plasma Enhanced Chemical Vapor Deposition Of Graphene, Otto Zietz, Samuel Olson, Brendan Coyne, Yilian Liu, Jun Jiao Nov 2020

Characterization And Manipulation Of Carbon Precursor Species During Plasma Enhanced Chemical Vapor Deposition Of Graphene, Otto Zietz, Samuel Olson, Brendan Coyne, Yilian Liu, Jun Jiao

Mechanical and Materials Engineering Faculty Publications and Presentations

To develop a synthesis technique providing enhanced control of graphene film quality and uniformity, a systematic characterization and manipulation of hydrocarbon precursors generated during plasma enhanced chemical vapor deposition of graphene is presented. Remote ionization of acetylene is observed to generate a variety of neutral and ionized hydrocarbon precursors, while in situ manipulation of the size and reactivity of carbon species permitted to interact with the growth catalyst enables control of the resultant graphene morphology. Selective screening of high energy hydrocarbon ions coupled with a multistage bias growth regime results in the production of 90% few-to-monolayer graphene on 50 nm …


Assessing The Relationship Between Organizational Management Factors And A Resilient Safety Culture In A Collegiate Aviation Program With Safety Management Systems (Sms), Daniel Kwasi Adjekum, Marcos Fernandez Tous Nov 2020

Assessing The Relationship Between Organizational Management Factors And A Resilient Safety Culture In A Collegiate Aviation Program With Safety Management Systems (Sms), Daniel Kwasi Adjekum, Marcos Fernandez Tous

Aviation Faculty Publications

Extant research advocates for assessing and continuously improving resilient safety culture in high-reliability organizations (HROs) such as aviation that has a fully functional Safety Management Systems (SMS). Perceptions on the relationship between four (4) organizational management factors (Principles, Policy, Procedures, Practices) and resilient safety culture in a collegiate aviation program was assessed using an online survey instrument drafted using Reason (2011) concept on safety resilience. Sample was drawn from aviation students, flight instructors, faculty and administrators. Structural Equation Model (SEM) and Causal Path Analysis (CPA) techniques were used to assess conceptual models. Results suggest good …


Determining Ground Elevations Covered By Vegetation On Construction Sites Using Drone-Based Orthoimage And Convolutional Neural Network, Yuhan Jiang, Yong Bai, Sisi Han Nov 2020

Determining Ground Elevations Covered By Vegetation On Construction Sites Using Drone-Based Orthoimage And Convolutional Neural Network, Yuhan Jiang, Yong Bai, Sisi Han

Civil and Environmental Engineering Faculty Research and Publications

Three-dimensional (3D) surveying of a construction site using an image-based method may produce incorrect ground elevation results at vegetation-covered regions, because the light rays are reflected on the surface of vegetation in front of the “truth” ground. This paper presents a convolutional neural network (CNN) method to identify and locate static vegetation using drone-based high-resolution orthoimages. The developed CNN-based image classification models are supplemented with an overlapping disassembling algorithm to generate , , , or small-patches as model inputs. The training datasets are 10 pairs of orthoimage and label-image dataset. Experimental results show that cropping a high-resolution image into 9,025 …


Wetting-Driven Formation Of Present-Day Loess Structure, Yanrong Li, Weiwei Zhang, Shengdi He, Adnan Aydin Nov 2020

Wetting-Driven Formation Of Present-Day Loess Structure, Yanrong Li, Weiwei Zhang, Shengdi He, Adnan Aydin

Faculty and Student Publications

© 2020 The Authors Present-day loess, especially Malan loess formed in Later Quaternary, has a characteristic structure composed of vertically aligned strong units and weak segments. Hypotheses describing how this structure forms inside original loess deposits commonly relate it to wetting-drying process. We tested this causal relationship by conducting unique experiments on synthetic samples of initial loess deposits fabricated by free-fall of loess particles. These samples were subjected to a wetting-drying cycle, and their structural evolutions were documented by close-up photography and CT scanning. Analysis of these records revealed three key stages of structural evolution: initiation (evenly distributed cracks appear …