Seven CU Engineering graduate students, plus an eighth CU Boulder student studying physics, have earned prestigious National Defense Science and Engineering Graduate Fellowships in fall 2020.
The fellowship program, established by Congress in 1989 and sponsored by the U.S. Army, U.S. Navy and U.S. Air Force, promotes education in science and engineering disciplines relevant to national defense. The highly competitive program supports promising U.S. scientists to pursue doctoral degrees. The three-year fellowships cover recipients' full tuition and fees and provide a $38,400 annual stipend, a $5,000 travel budget for professional development, and up to $1,200 a year in health insurance.
This year's recipients are studying in the Departments of Chemical and Biological Engineering, Electrical, Computer & Energy Engineering, and Smead Aerospace Engineering Sciences.
— Compiled by Emily Adams, Jonathan Raab and Jeff Zehnder.
Adam Christopherson
Department: Smead Aerospace Engineering Sciences
Advisor: Kurt Maute
Lab: Topology Optimization Laboratory
My research focuses on developing strategies for level set XFEM topology optimization based on a relatively new finite element analysis method called finite element exterior calculus (FEEC). While a large number of topology optimization tools rely on the finite element method, FEEC is a different framework in the sense that it bases the finite element method on the calculus of differential forms. FEEC was developed as a powerful structure-preserving analysis method, and has since been studied in the mathematics community and for applications such as computational electromagnetism. However, we have predicted several advantages when applying this method to topology optimization as well given the structure-preserving nature of these finite element discretizations.
I am excited to work on this research because it will allow for more robust design optimization when complex physics and design domains are involved. This research is primarily aimed at aerospace applications, but other fields can likely benefit from the framework as well.
Paige Danielson
Department: Electrical, Computer & Energy Engineering
Advisor: Zoya Popovic
Lab: Microwave & RF Research Group
My research addresses new types of radio-frequency circuits and antennas for communications and sensing at frequencies in the 6-30GHz range. Specifically, I am interested in improving the power efficiency of active transmit antenna arrays, since they are thermally-limited as frequency increases. In addition, I will focus on designing beam-forming networks with the goal of transmitting multiple signals in multiple directions simultaneously. This will require design of broadband antenna elements and arrays, power amplifiers, phase shifters and low-loss interconnects. Initially, I will focus on a frequency range commonly utilized for military applications, and later scale up to 5G and satellite bands.
Kathryn Mains
Department: Chemical & Biological Engineering
Advisor: Jerome Fox
Lab: Fox Research Group
I am working to eliminate our nation’s dependence on fossil fuels—a technological achievement that could slow climate change, stabilize energy markets and enhance energy security—by developing biological systems that build oleochemicals from renewable resources.
As a graduate student, I will dissect the biochemical controls that allow sophisticated multi-enzyme systems to build well defined sets of fatty acids, and I will use the principles, thus, resolved, to engineer microbes that produce oleochemical precursors of surfactants, fuels and fabrics.
After graduation, I hope to join a national or academic lab that uses microbes to build fuels, degrade chemicals (e.g., plastics), or assemble complex materials (e.g., circuits) with applications in defense. Ultimately, I hope to lead a team of researchers on the development of new approaches to the microbial synthesis of complex chemical systems—from a bioscavenger or drop-in fuel to a device—from renewable starting materials or waste products.
Luke Peterson
Department: Smead Aerospace Engineering Sciences
Advisor: Dan Scheeres
Lab: Celestial and Spaceflight Mechanics Laboratory
I work on a class of higher-dimensional orbits called quasi-periodic orbits or quasi-periodic tori. If we consider the gravitational attraction of the planets as a dynamical system, i.e. a system that evolves over time, then there are special solutions to the system. The 0-dimensional solution is called an equilibrium point: if you start there, you stay put. The 1-dimensional solution is called a periodic orbit: similar to a circle or a loop, if you're on a periodic orbit you can move forward, and you eventually repeat yourself. The 2- and higher-dimensional solutions are called quasi-periodic orbits, and it is these solutions that I study. Quasi-periodic orbits are trajectories that never repeat and, crucially, lie on the surface of a torus. An example of a torus in 2-dimensions is a donut. If these trajectories repeated themselves, they would be periodic, not quasi-periodic. The data that describes quasi-periodic tori is non-unique, in other words, two different sets of data can describe the same quasi-periodic torus.
In my time at CU Boulder thus far, I have developed a fundamental representation of quasi-periodic tori. In the remainder of my time at CU, I hope to investigate connections between quasi-periodic orbits for efficient mission design throughout the solar system.
Eric Rappeport
Department: Electrical, Computer & Energy Engineering
Advisor: Won Park
Lab: Nanophotonics Lab
My research focuses on utilizing upconverting nanoparticles for biomedical imaging applications. Current technology uses fluorescent dyes, which require ultra-violet light excitation. However, this excitation creates high background noise, due to cellular auto-fluorescence, and damages the cells. Upconverting nanoparticles (UCNPs) are novel imaging agents that convert near-infrared (980 nm) into visible light. Due to this infrared excitation, these particles yield significantly higher signal-to-noise ratios (SNR) with little to no cellular damage. In addition, these nanoparticles can be functionalized to become sensitive to physiochemical effects such as pH or temperature. This functionalization is the current focus of my research, where I am hoping to use them to detect small pH changes at the cellular level. Such a sensor could greatly improve our ability to distinguish tumor cells from their healthy alternatives.
Kyle Schlafmann
Department: Chemical & Biological Engineering
Advisor: Timothy White
Lab: Responsive and Programmable Materials Group
My interest in developing, advancing and implementing novel optical responses in polymeric materials broadly serves the needs of the Department of Defense and specifically the Air Force. This connection to a mission-oriented research agency also goes a long way toward enabling my career goal of becoming a technical leader working at the interface of fundamental research and applied directives benefiting our society. I intend to take full advantage of the opportunities available to me through the NDSEG fellowship program.
To me, the most important aspects of this award are the personal connections to be made with STEM leaders, both within the DOD and abroad. Through summer research exchanges, potential collaborations with DOD researchers, and travel allocations for national conferences, I hope to add a unique and enlightening context to my education here at the University of Colorado Boulder, while also preparing myself professionally for the road ahead.
Samantha Sheppard
Department: Smead Aerospace Engineering Sciences
Advisor: John Farnsworth
Lab: Experimental Aerodynamics Laboratory
In my first year at the University of Colorado Boulder my research focused on the preliminary development of a turbulent synthetic surface layer in a low speed wind tunnel. The continuation of this work will support the development of improved boundary conditions for Large Eddy Simulations (LES). The primary motivation for this work is to improve LES modeling of the Atmospheric Boundary Layer. Moving forward, I will be contributing to a collaborative Strategic Environment Research and Development Program project by conducting flow measurements of flames in a novel sloping wind tunnel to validate and inform computational wildfire models. The aim of this project is to develop improved computational capability to reliably predict wildfire behavior. My work within this project will contribute to the validation of these models as well as extending the current understanding of the development of 3D structures in a finite span flame front and the effect of these structures on the flame propagation.