Engineering Commons^™

Developing Open Source Software Using Version Control Systems: An Introduction To The Git Language For Documenting Your Computational Research, Jared D. Smith, Jonathan D. Herman

All ECSTATIC Materials

Version control systems track the history of code as it is committed (saved) by any number of developers. Have you made a coding error and cannot debug it? Version control systems allow for resetting code back to when it worked, and show what code has changed since previous commits.

The contents of this lecture provide an introduction to the git version control language, GitHub for cloud hosting open source code repositories, and tutorials that demonstrate common and useful git and GitHub practices. This lecture is intended to be coupled with a discussion on creating reproducible computational research.

The zipped folder …

Fast Summarizing Algorithm For Polygonal Statistics Over A Regular Grid, Scott Haag, David G. Tarboton, Martyn Smith, Ali Shokoufandeh

Publications

We describe a data structure and associated algorithm called Fast Zonal Statistics (FZS) for the retrieval of the summary characteristics of an arbitrary polygon derived from a regular grid. The FZS algorithm can return numerical (e.g., mean, sum, and count) attributes for a polygonal object over a regular grid (e.g., raster data model). The computational complexity of the FZS algorithm is constant in relation to the length of the polygon perimeter. This contrasts with existing approaches which scale in relation to the polygon area, therefore we expect and measure geometric decreases in execution time using the proposed approach for simple …

3-D Printed Hybrid Propulsion Solutions For Smallsat Lunar Landing And Sample Return, Stephen A. Whitmore

Funded Research Records

No abstract provided.

Implications Of Soil And Canopy Temperature Uncertainty In The Estimation Of Surface Energy Fluxes Using Tseb2t And High-Resolution Imagery In Commercial Vineyards, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Héctor Nieto, Mac Mckee, Lawrence Hipps, Joseph Alfieri, John H. Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Luis Sanchez, Nick Dokoozlian

Civil and Environmental Engineering Faculty Publications

Estimation of surface energy fluxes using thermal remote sensing–based energy balance models (e.g., TSEB2T) involves the use of local micrometeorological input data of air temperature, wind speed, and incoming solar radiation, as well as vegetation cover and accurate land surface temperature (LST). The physically based Two-source Energy Balance with a Dual Temperature (TSEB2T) model separates soil and canopy temperature (Ts and Tc) to estimate surface energy fluxes including Rn, H, LE, and G. The estimation of Ts and Tc components for the TSEB2T model relies on the linear relationship between the composite land surface temperature and a vegetation index, namely …

To What Extent Does The Eddy Covariance Footprint Cutoff Influence The Estimation Of Surface Energy Fluxes Using Two Source Energy Balance Model And High-Resolution Imagery In Commercial Vineyards?, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Héctor Nieto, Mac Mckee, Lawrence Hipps, Joseph Alfieri, John H. Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Louis Sanchez, Nick Dokoozlian

Civil and Environmental Engineering Faculty Publications

Validation of surface energy fluxes from remote sensing sources is performed using instantaneous field measurements obtained from eddy covariance (EC) instrumentation. An eddy covariance measurement is characterized by a footprint function / weighted area function that describes the mathematical relationship between the spatial distribution of surface flux sources and their corresponding magnitude. The orientation and size of each flux footprint / source area depends on the micro-meteorological conditions at the site as measured by the EC towers, including turbulence fluxes, friction velocity (u_star), and wind speed, all of which influence the dimensions and orientation of the footprint. The …

Estimation Of Autoregressive Parameters From Noisy Observations Using Iterated Covariance Updates, Todd K. Moon, Jacob H. Gunther

Electrical and Computer Engineering Faculty Publications

Estimating the parameters of the autoregressive (AR) random process is a problem that has been well-studied. In many applications, only noisy measurements of AR process are available. The effect of the additive noise is that the system can be modeled as an AR model with colored noise, even when the measurement noise is white, where the correlation matrix depends on the AR parameters. Because of the correlation, it is expedient to compute using multiple stacked observations. Performing a weighted least-squares estimation of the AR parameters using an inverse covariance weighting can provide significantly better parameter estimates, with improvement increasing with …

Empirical Models For Predicting Water And Heat Flow Properties Of Permafrost Soils, Michael T. O'Connor, M. Bayani Cardenas, Stephen B. Ferencz, Yue Wu, Bethany T. Neilson, Jingyi Chen, George W. Kling

Publications

Warming and thawing in the Arctic are promoting biogeochemical processing and hydrologic transport in carbon‐rich permafrost and soils that transfer carbon to surface waters or the atmosphere. Hydrologic and biogeochemical impacts of thawing are challenging to predict with sparse information on arctic soil hydraulic and thermal properties. We developed empirical and statistical models of soil properties for three main strata in the shallow, seasonally thawed soils above permafrost in a study area of ~7,500 km² in Alaska. The models show that soil vertical stratification and hydraulic properties are predictable based on vegetation cover and slope. We also show that …

Estimation Of Evapotranspiration And Energy Fluxes Using A Deep-Learning-Based High-Resolution Emissivity Model And The Two-Source Energy Balance Model With Suas Information, Alfonso F. Torres-Rua, Andres Ticlavilca, Mahyar Aboutalebi, Héctor Nieto, Maria Mar Alsina, Alex White, John H. Prueger, Joseph Alfieri, Lawrence Hipps, Lynn Mckee, William Kustas, Calvin Coopmans, Nick Dokoozlian

Civil and Environmental Engineering Faculty Publications

Surface temperature is necessary for the estimation of energy fluxes and evapotranspiration from satellites and airborne data sources. For example, the Two-Source Energy Balance (TSEB) model uses thermal information to quantify canopy and soil temperatures as well as their respective energy balance components. While surface (also called kinematic) temperature is desirable for energy balance analysis, obtaining this temperature is not straightforward due to a lack of spatially estimated narrowband (sensor-specific) and broadband emissivities of vegetation and soil, further complicated by spectral characteristics of the UAV thermal camera. This study presents an effort to spatially model narrowband and broadband emissivities for …

Isolation And Selective Glycosylation Of Antisalmonellal Anthraquinones From The Stem Bark Of Morinda Lucida Benth. (Rubiaceae), Napoleon A. Mfonku, James A. Mbah, Norbert Kodjio, Donatien Gatsing, Jixun Zhan

Biological Engineering Faculty Publications

In this work we report the isolation, identification and antibacterial activity of two anthraquinones, 2-hydroxy-1-methoxyanthraquinone (1) and 2,5-dihydroxy-1-methoxy-6-methoxymethylanthraquinone (2), from the stem bark of Morinda lucida. These two natural products were selectively converted into two new glycosylated derivatives, 2-hydroxy-1-methoxyanthraquinone-4′-O-methyl-2-O-β-d-glucopyranoside (3) and 2,5-dihydroxy-1-methoxy-6-methoxymethylanthraquinone-4′-O-methyl-2-O-β-d-glucopyranoside (4) by the filamentous fungus Beauveria bassiana ATCC 7159. Structure elucidation was accomplished based on the 1D and 2D NMR, IR and mass spectra. The glycosylated compounds 3 and 4 showed higher in vitro antibacterial activity against Salmonella enterica subsp. enterica sérovars Typhimurim (MIC of 8 μg/mL each) than the corresponding aglycons 1 and 2 (MIC of …

Quantitative Assessment Of Contested Water Uses And Management In The Conflict-Torn Yarmouk River Basin, Nicolas Avisse, Amaury Tilmant, David E. Rosenberg, Samer Talozi

Civil and Environmental Engineering Faculty Publications

The Yarmouk River basin is shared between Syria, Jordan, and Israel. Since the 1960s, Yarmouk River flows have declined more than 85% despite the signature of bilateral agreements. Syria and Jordan blame each other for the decline and have both developed their own explanatory narratives: Jordan considers that Syria violated their 1987 agreement by building more dams than what was agreed on, while Syria blames climate change. In fact, because the two countries do not share information, neither on hydrological flows nor on water management, it is increasingly difficult to distinguish between natural and anthropogenic factors affecting the flow regime. …

Integrating Hydrologic Modeling Web Services With Online Data Sharing To Prepare, Store, And Execute Hydrologic Models, Tian Gan, David G. Tarboton, Pabitra Dash, Tseganeh Z. Gichamo, Jeffery S. Horsburgh

Civil and Environmental Engineering Faculty Publications

Web based applications, web services, and online data and model sharing technology are becoming increasingly available to support hydrologic research. This promises benefits in terms of collaboration, computer platform independence, and reproducibility of modeling workflows and results. In this research, we designed an approach that integrates hydrologic modeling web services with an online data sharing system to support web-based simulation for hydrologic models. We used this approach to integrate example systems as a case study to support reproducible snowmelt modeling for a test watershed in the Colorado River Basin, USA. We demonstrated that this approach enabled users to work within …

Energy Dissipation Of Type A Piano Key Weirs, Kam R. Eslinger, Brian M. Crookston

Publications

A Piano Key weir (PK weir) is a nonlinear, labyrinth-type weir well suited for rehabilitation projects due to a relatively small footprint and the ability to pass large discharges for lesser upstream-head values when compared with other weir types. A critical component of a hydraulic structure is the energy-dissipative properties. Currently, information and guidance is limited, with previous energy dissipation studies of PK weirs primarily of specific projects. Therefore, to document and quantify energy dissipation, four laboratory-scale Type A PK weir models with different width ratios (W_i/W_o) were studied, with 255 tests comprising this new …

Change Of Exposure Time Mid-Test In High Temperature Dic Measurement, Thinh Quang Thai, Adam J. Smith, Robert J. Rowley, Paul R. Gradl, Ryan B. Berke

Mechanical and Aerospace Engineering Faculty Publications

Performing digital image correlation (DIC) at extreme temperatures has been greatly challenging due to the radiation which saturates the camera sensor. At such high temperatures, the light intensity emitted from an object is occasionally so powerful that the acquired images are overwhelmingly saturated. This induces data loss, potentially ruining the test, thus requiring the user to restart the test. For this reason, selection of an appropriate camera sensitivity plays a crucial role prior to beginning the test. Exposure time is a factor contributing to camera sensitivity and it is the easiest setting to manipulate during the test since it introduces …

Acute Mechanical Stress In Primary Porcine Rpe Cells Induces Angiogenic Factor Expression And In Vitro Angiogenesis, Farhad Farjood, Amir Ahmadpour, Sassan Ostvar, Elizabeth Vargis

Biological Engineering Faculty Publications

Background

Choroidal neovascularization (CNV) is a major cause of blindness in patients with age-related macular degeneration. CNV is characterized by new blood vessel growth and subretinal fluid accumulation, which results in mechanical pressure on retinal pigment epithelial (RPE) cells. The overexpression of RPE-derived angiogenic factors plays an important role in inducing CNV. In this work, we investigated the effect of mechanical stress on the expression of angiogenic factors in porcine RPE cells and determined the impact of conditioned medium on in-vitro angiogenesis.

Results

The goal of this study was to determine whether low levels of acute mechanical stress during early …

Nytrox As “Drop-In” Replacement For Gaseous Oxygen In Smallsat Hybrid Propulsion Systems, Stephen A. Whitmore

Mechanical and Aerospace Engineering Faculty Publications

A medical grade nitrous oxide (N₂O) and gaseous oxygen (GOX) “Nytrox” blend is investigated as a volumetrically-efficient replacement for GOX in SmallSat-scale hybrid propulsion systems. Combined with 3-D printed acrylonitrile butadiene styrene (ABS), the propellants represent a significantly safer, but superior performing, alternative to environmentally-unsustainable spacecraft propellants like hydrazine. In a manner analogous to the creation of soda-water using dissolved carbon dioxide, Nytrox is created by bubbling GOX under pressure into N₂O until the solution reaches saturation. Oxygen in the ullage dilutes N₂O vapor and increases the required decomposition energy barrier by several orders …

Reu Site: Engineering Education Research On Undergraduate Engineering Students' Problem Solving Capacity, Oenardi Lawanto

Funded Research Records

No abstract provided.

Dynamics Of The Ionospheric Energetics (Dione) 2018, Ryan Davidson, Charles Swenson

Funded Research Records

No abstract provided.

Collaborative Sharing Of Multidimensional Space-Time Date In A Next Generation Hydrologic Information System, Tian Gan, David G. Tarboton, Jeffery S. Horsburgh, Pabitra Dash, Ray Idaszak, Hong Yi

Civil and Environmental Engineering Faculty Publications

In hydrologic research, there is a need to manage, archive, and publish data in a discoverable way to increase data reuse, transparency, and reproducibility. Multidimensional space-time data are commonly used in hydrologic research, and systems are needed for sharing and exchanging such data. Simply exchanging files may result in loss of metadata information and can be challenging when files are large. We developed an approach to manage, share, and publish multidimensional space-time data in HydroShare, a next generation hydrologic information system and domain specific repository. This paper presents the design, development, and testing of this approach. We selected the Network …

Lecture Notes: Multi-Objective Optimization, Lina Sela

All ECSTATIC Materials

No abstract provided.

Robust Secure Wireless Powered Miso Cognitive Mobile Edge Computing, Boyang Liu, Jiajia Song, Jin Wang, Haijan Sun, Qun Wang

Electrical and Computer Engineering Student Research

Wireless power transfer (WPT) and cognitive radio (CR) are two promising techniques in designing mobile-edge computing (MEC) systems. In this paper, we study a robust secure wireless powered multiple-input single-output (MISO) cognitive MEC system, which integrates several techniques: physical-layer security, WPT, CR, underlay spectrum sharing and MEC. Three optimization problems are formulated to minimize the total transmission power (TTP) of the primary transmitter (PT) and the secondary base station (SBS) under perfect channel state information (CSI) model, bounded CSI error model and the probabilistic CSI error model, respectively. The formulated problems are nonconvex and hard to solve. Three two-phase iterative …

Lecture Notes: Nonlinear Optimization And Matlab Optimization Toolbox Example, Lina Sela

All ECSTATIC Materials

No abstract provided.

Video Conversations - The Future Of The Colorado River, John C. Schmidt, David E. Rosenberg

All ECSTATIC Materials

This video series explores key Colorado River management issues with key managers across the basin. Video discussions in the table on the next page are presented in the order they were recorded. Topics include river ecosystems, California, Upper Basin, Tribal, and Federal perspectives, as well as future hydrology and climate. Each video runs for 60 to 90 minutes. Speakers start by describing how they got to the place they are professionally. There are prepared remarks and questions and answers from participants who attended at the time the video was recorded. Links to suggested readings are provided. Click the VIDEO url …

Extending Water Resources Performance Metrics To River Ecosystems, Belize A. Lane, J. Pablo Ortiz-Partida, Samuel Sandoval-Solis

Civil and Environmental Engineering Faculty Publications

A persistent challenge in integrated water management is the ability to accurately evaluate human and ecological tradeoffs. Two-dimensional (2D) hydraulic models are frequently used to evaluate water management alternatives concerning aquatic species physical habitat needs or preferences. Recent studies have assessed the timing or duration of suitable habitat conditions, but no standardized approach exists to integrate and interpret ecohydraulic model outputs within a water management framework. Such an approach is needed to maximize the information obtained from model outputs and to facilitate communication between river scientists and water managers. This study presents a general framework to aggregate and summarize 2D …

Proper Orthogonal Decomposition And Recurrence Map For The Identification Of Spatial–Temporal Patterns In A Low-Re Wake Downstream Of Two Cylinders, Meihua Zhang, Zhongquan Charlie Zheng, Huixuan Wu

Mechanical and Aerospace Engineering Faculty Publications

Flow decomposition methods provide systematic ways to extract the flow modes, which can be regarded as the spatial distribution of a coherent structure. They have been successfully used in the study of wake, boundary layer, and mixing. However, real flow structures also possess complex temporal patterns that can hardly be captured using the spatial modes obtained in the decomposition. In order to analyze the temporal variation of coherent structures in a complex flow field, this paper studies the recurrence in phase space to identify the pattern and classify the evolution of the flow modes. The recurrence pattern depends on the …

Reducing Road Wear While Ensuring Comfort And Charging Constraints For Dynamically Charged Passenger Vehicles Through Noise-Shaped Path Variations, Clint Jay Ferrin, Randall Christensen

Electrical and Computer Engineering Faculty Publications

Dynamically charged vehicles suffer from power loss during wireless power transfer due to receiver and transmitter coil misalignment while driving. Autonomous, dynamically charged vehicles can maximize wireless power transfer by minimizing the misalignment, but the repeated high-precision driving increases road wear. To avoid unnecessary road wear and rutting, a noise shaping filter is proposed that adds variability to a vehicle's trajectory that complies with passenger acceleration and position constraints. However, introducing variability into an optimal charging path also risks depleting battery life prior to destination arrival. Therefore, a path planner is proposed that guarantees average charge within a specified probability …

Reu Site: Tomorrow's Nanomanufacturing: Engineering With Science (Tnews), Keith Roper

Funded Research Records

No abstract provided.

Initial Development Of Corn Seedlings After Seed Priming With Nanoscale Synthetic Zinc Oxide, Michel Esper Neto, David W. Britt, Lorena Moreira Lara, Anthony Cartwright, Rayssa Fernanda De Santos, Tadeu Takeyoshi Inoue, Marcelo Augusto Batista

Biological Engineering Faculty Publications

Nanofertilizers are increasingly explored for sustainable micronutrient delivery in agriculture. Pre-treating seeds with nanofertilizers prior to planting (i.e., seed priming) reduces concerns about nanoparticle (NP) fertilizer non-target dispersion; however, priming formulations and concentrations must be carefully selected to avoid germination inhibition and toxicity. Here we investigate changes in corn seed germination and seedling development after seed priming with ZnO NPs, ZnO bulk and ZnCl₂. To evaluate the effects sterile seeds were immersed in priming solutions of 0, 20, 40, 80, 160 mg L⁻¹ Zn for the three Zn sources. Following an 8 h priming the seeds were …

Reformulated Red Mud: A Robust Catalyst For In Situ Catalytic Pyrolysis Of Biomass, Foster Agblevor, Huamin Wang, S. Beis, K. Christian, A. Slade, O. Hietsoi, D. M. Santosa

Biological Engineering Faculty Publications

Biomass feedstocks contain inorganic compounds generally classified as ash. The ash consists of compounds of potassium, calcium, magnesium, silicon, phosphorus. and other elements. These elements have been reported to influence both the pyrolysis reactions as well as the destabilization of the pyrolysis oils during storage. The inorganic elements have also been reported to deposit on catalyst surfaces during in situ catalytic pyrolysis leading to the eventual deactivation of acidic catalysts such as zeolites. The deposition of inorganic elements and their effects on formulated red mud (FRM) catalyst during in situ catalytic pyrolysis of pinyon juniper wood was investigated. The inorganic …

Ground And In-Flight Calibration Of The Osiris-Rex Camera Suite, D. R. Golish, C. Drouet D'Aubigny, B. Rizk, D. N. Dellagiustina, P. H. Smith, K. Becker, N. Shultz, T. Stone, M. K. Barker, E. Mazarico, E. Tatsumi, R. W. Gaskell, L. Harrison, C. Merrill, C. Fellows, B. Williams, S. O'Dougherty, Michael Whitely, Jed Hancock, B. E. Clark, C. W. Hergenrother, D. S. Lauretta

Space Dynamics Laboratory Publications

The OSIRIS-REx Camera Suite (OCAMS) onboard the OSIRIS-REx spacecraft is used to study the shape and surface of the mission’s target, asteroid (101955) Bennu, in support of the selection of a sampling site. We present calibration methods and results for the three OCAMS cameras—MapCam, PolyCam, and SamCam—using data from pre-flight and in-flight calibration campaigns. Pre-flight calibrations established a baseline for a variety of camera properties, including bias and dark behavior, flat fields, stray light, and radiometric calibration. In-flight activities updated these calibrations where possible, allowing us to confidently measure Bennu’s surface. Accurate calibration is critical not only for establishing a …

Influence Of Model Grid Size On The Estimation Of Surface Fluxes Using The Two Source Energy Balance Model And Suas Imagery In Vineyards, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Hector Nieto, Mac Mckee, Lawrence E. Hipps, David King Stevens, Joseph Alfieri, John Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Luis Sanchez, Nick Dokoozlian

Civil and Environmental Engineering Faculty Publications

Evapotranspiration (ET) is a key variable for hydrology and irrigation water management,with significant importance in drought-stricken regions of the western US. This is particularly true for California, which grows much of the high-value perennial crops in the US. The advent of small Unmanned Aerial System (sUAS) with sensor technology similar to satellite platforms allows for the estimation of high-resolution ET at plant spacing scale for individual fields. However, while multiple efforts have been made to estimate ET from sUAS products, the sensitivity of ET models to different model grid size/resolution in complex canopies, such as vineyards, is still unknown.The variability …