Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 5 of 5

Full-Text Articles in Engineering

Multimodal Imaging Of Structural Concrete Using Image Fusion And Deep Learning, Sina Mehdinia Aug 2022

Multimodal Imaging Of Structural Concrete Using Image Fusion And Deep Learning, Sina Mehdinia

Dissertations and Theses

Concrete structures may be exposed to a variety of loads and environments during their service life. Non-destructive testing (NDT) techniques can be helpful in evaluating the condition of a structure. Imaging provides a visual representation of the interior of concrete and its condition non-destructively. Ground penetrating radar (GPR) and ultrasonic echo array (UEA) using electromagnetic and stress waves, respectively, provide the data that can be used to reconstruct an image. In this PhD dissertation, image reconstruction and fusion algorithms, simulation, and a deep learning model were investigated with the goal to lay the foundation for enhanced imaging applications for concrete. …


Learning From Machines: Insights In Forest Transpiration Using Machine Learning Methods, Morgan Tholl Jul 2022

Learning From Machines: Insights In Forest Transpiration Using Machine Learning Methods, Morgan Tholl

Dissertations and Theses

Machine learning has been used as a tool to model transpiration for individual sites, but few models are capable of generalizing to new locations without calibration to site data. Using the global SAPFLUXNET database, 95 tree sap flow data sites were grouped using three clustering strategies: by biome, by tree functional type, and through use of a k-means unsupervised clustering algorithm. Two supervised machine learning algorithms, a random forest algorithm and a neural network algorithm, were used to build machine learning models that predicted transpiration for each cluster. The performance and feature importance in each model were analyzed and compared …


Mass Capacity Analysis Of Stormwater Control Measures Using Synthetic Stormwater With Silica, Organic And Hydrocarbon Constituents, Craig Michael Fairbaugh Mar 2022

Mass Capacity Analysis Of Stormwater Control Measures Using Synthetic Stormwater With Silica, Organic And Hydrocarbon Constituents, Craig Michael Fairbaugh

Dissertations and Theses

Stormwater control measure (SCM) performance is well studied regarding solids removal; however, analysis of mass loading capacity, long-term performance, and maintenance demands are challenging due to the variability and multiple constituents inherent in urban stormwater. This research examines the long-term water quality performance and sediment mass capacity of two common SCMs: high rate biofiltration (HRBF) and conventional bioretention (BRT). Pollutant removal trials were conducted in a laboratory setting per the New Jersey Department of Environmental Protection (NJDEP) filtration protocol in two phases: the first using inorganic sediment per the NJDEP protocol, the second phase with the addition of organic sediment …


Seismic Performance Design Criteria Of Existing Bridge Bent Plastic Hinge Region And Rapid Repair Measures Of Earthquake Damaged Bridges Considering Future Resilience, A K M Golam Murtuz Mar 2022

Seismic Performance Design Criteria Of Existing Bridge Bent Plastic Hinge Region And Rapid Repair Measures Of Earthquake Damaged Bridges Considering Future Resilience, A K M Golam Murtuz

Dissertations and Theses

The main objective of this research was to evaluate the seismic performance of existing sub-standard reinforced concrete (RC) bridge column-spread footing subassemblies and to quantify the material strain limits through a full-scale experimental program. A total of six column-footing test specimens with pre-1990 construction details were subjected to reverse cyclic lateral loading, utilizing a conventional three-cycle symmetric loading protocol and a protocol representing the demands expected from a CSZ earthquake. Additionally, the tests were designed so that variable axial loading could be applied to simulate the secondary load effects experienced during an earthquake in a column that is part of …


The Impact Of New Light Rail Service On Employment Growth In Portland, Oregon, Lahar Santra Jan 2022

The Impact Of New Light Rail Service On Employment Growth In Portland, Oregon, Lahar Santra

Dissertations and Theses

This study quantitatively examines the impact of the new Light Rail Transit (LRT) service on employment growth in retail, knowledge, and service sectors before and after opening the LRT. At the corridor level, this study conducts a case study of Greenline in Southeast Portland, Oregon. The results of the corridor level study suggest that the new LRT service increased employment along the Greenline corridor among all the three sectors of interest- retail, knowledge, service in the long-term (ten years) while having slightly different results for the short-term (five years), likely due to the slow growth of LRT benefits. This study …