Matching Items (50)
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- All Subjects: Mechanical Engineering
- Creators: Rykaczewski, Konrad
- Creators: Wang, Robert
Description
Additive manufacturing (AM) describes an array of methods used to create a 3D object layer by layer. The increasing popularity of AM in the past decade has been due to its demonstrated potential to increase design flexibility, produce rapid prototypes, and decrease material waste. Temporary supports are an inconvenient necessity in many metal AM parts. These sacrificial structures are used to fabricate large overhangs, anchor the part to the build substrate, and provide a heat pathway to avoid warping. Polymers AM has addressed this issue by using support material that is soluble in an electrolyte that the base material is not. In contrast, metals AM has traditionally approached support removal using time consuming, costly methods such as electrical discharge machining or a dremel.
This work introduces dissolvable supports to single- and multi-material metals AM. The multi-material approach uses material choice to design a functionally graded material where corrosion is the functionality being varied. The single-material approach is the primary focus of this thesis, leveraging already common post-print heat treatments to locally alter the microstructure near the surface. By including a sensitizing agent in the ageing heat treatment, carbon is diffused into the part decreasing the corrosion resistance to a depth equal to at least half the support thickness. In a properly chosen electrolyte, this layer is easily chemically, or electrochemically removed. Stainless steel 316 (SS316) and Inconel 718 are both investigated to study this process using two popular alloys. The microstructure evolution and corrosion properties are investigated for both. For SS316, the effect of applied electrochemical potential is investigated to describe the varying corrosion phenomena induced, and the effect of potential choice on resultant roughness. In summary, a new approach to remove supports from metal AM parts is introduced to decrease costs and further the field of metals AM by expanding the design space.
This work introduces dissolvable supports to single- and multi-material metals AM. The multi-material approach uses material choice to design a functionally graded material where corrosion is the functionality being varied. The single-material approach is the primary focus of this thesis, leveraging already common post-print heat treatments to locally alter the microstructure near the surface. By including a sensitizing agent in the ageing heat treatment, carbon is diffused into the part decreasing the corrosion resistance to a depth equal to at least half the support thickness. In a properly chosen electrolyte, this layer is easily chemically, or electrochemically removed. Stainless steel 316 (SS316) and Inconel 718 are both investigated to study this process using two popular alloys. The microstructure evolution and corrosion properties are investigated for both. For SS316, the effect of applied electrochemical potential is investigated to describe the varying corrosion phenomena induced, and the effect of potential choice on resultant roughness. In summary, a new approach to remove supports from metal AM parts is introduced to decrease costs and further the field of metals AM by expanding the design space.
ContributorsLefky, Christopher (Author) / Hildreth, Owen (Thesis advisor) / Chawla, Nikhilesh (Committee member) / Azeredo, Bruno (Committee member) / Rykaczewski, Konrad (Committee member) / Nian, Qiong (Committee member) / Arizona State University (Publisher)
Created2018
Description
The objective of this dissertation is to study the use of metamaterials as narrow-band and broadband selective absorbers for opto-thermal and solar thermal energy conversion. Narrow-band selective absorbers have applications such as plasmonic sensing and cancer treatment, while one of the main applications of selective metamaterials with broadband absorption is efficiently converting solar energy into heat as solar absorbers.
This dissertation first discusses the use of gold nanowires as narrow-band selective metamaterial absorbers. An investigation into plasmonic localized heating indicated that film-coupled gold nanoparticles exhibit tunable selective absorption based on the size of the nanoparticles. By using anodized aluminum oxide templates, aluminum nanodisc narrow-band absorbers were fabricated. A metrology instrument to measure the reflectance and transmittance of micro-scale samples was also developed and used to measure the reflectance of the aluminum nanodisc absorbers (220 µm diameter area). Tuning of the resonance wavelengths of these absorbers can be achieved through changing their geometry. Broadband absorption can be achieved by using a combination of geometries for these metamaterials which would facilitate their use as solar absorbers.
Recently, solar energy harvesting has become a topic of considerable research investigation due to it being an environmentally conscious alternative to fossil fuels. The next section discusses the steady-state temperature measurement of a lab-scale multilayer solar absorber, named metafilm. A lab-scale experimental setup is developed to characterize the solar thermal performance of selective solar absorbers. Under a concentration factor of 20.3 suns, a steady-state temperature of ~500 degrees Celsius was achieved for the metafilm compared to 375 degrees Celsius for a commercial black absorber under the same conditions. Thermal durability testing showed that the metafilm could withstand up to 700 degrees Celsius in vacuum conditions and up to 400 degrees Celsius in atmospheric conditions with little degradation of its optical and radiative properties. Moreover, cost analysis of the metafilm found it to cost significantly less ($2.22 per square meter) than commercial solar coatings ($5.41-100 per square meter).
Finally, this dissertation concludes with recommendations for further studies like using these selective metamaterials and metafilms as absorbers and emitters and using the aluminum nanodiscs on glass as selective filters for photovoltaic cells to enhance solar thermophotovoltaic energy conversion.
This dissertation first discusses the use of gold nanowires as narrow-band selective metamaterial absorbers. An investigation into plasmonic localized heating indicated that film-coupled gold nanoparticles exhibit tunable selective absorption based on the size of the nanoparticles. By using anodized aluminum oxide templates, aluminum nanodisc narrow-band absorbers were fabricated. A metrology instrument to measure the reflectance and transmittance of micro-scale samples was also developed and used to measure the reflectance of the aluminum nanodisc absorbers (220 µm diameter area). Tuning of the resonance wavelengths of these absorbers can be achieved through changing their geometry. Broadband absorption can be achieved by using a combination of geometries for these metamaterials which would facilitate their use as solar absorbers.
Recently, solar energy harvesting has become a topic of considerable research investigation due to it being an environmentally conscious alternative to fossil fuels. The next section discusses the steady-state temperature measurement of a lab-scale multilayer solar absorber, named metafilm. A lab-scale experimental setup is developed to characterize the solar thermal performance of selective solar absorbers. Under a concentration factor of 20.3 suns, a steady-state temperature of ~500 degrees Celsius was achieved for the metafilm compared to 375 degrees Celsius for a commercial black absorber under the same conditions. Thermal durability testing showed that the metafilm could withstand up to 700 degrees Celsius in vacuum conditions and up to 400 degrees Celsius in atmospheric conditions with little degradation of its optical and radiative properties. Moreover, cost analysis of the metafilm found it to cost significantly less ($2.22 per square meter) than commercial solar coatings ($5.41-100 per square meter).
Finally, this dissertation concludes with recommendations for further studies like using these selective metamaterials and metafilms as absorbers and emitters and using the aluminum nanodiscs on glass as selective filters for photovoltaic cells to enhance solar thermophotovoltaic energy conversion.
ContributorsAlshehri, Hassan (Author) / Wang, Liping (Thesis advisor) / Phelan, Patrick (Committee member) / Rykaczewski, Konrad (Committee member) / Wang, Robert (Committee member) / Yu, Hongbin (Committee member) / Arizona State University (Publisher)
Created2018
Description
When air is supplied to a conditioned space, the temperature and humidity of the air often contribute to the comfort and health of the occupants within the space. However, the vapor compression system, which is the standard air conditioning configuration, requires air to reach the dew point for dehumidification to occur, which can decrease system efficiency and longevity in low temperature applications.
To improve performance, some systems dehumidify the air before cooling. One common dehumidifier is the desiccant wheel, in which solid desiccant absorbs moisture out of the air while rotating through circular housing. This system improves performance, especially when the desiccant is regenerated with waste or solar heat; however, the heat of regeneration is very large, as the water absorbed during dehumidification must be evaporated. N-isopropylacrylamide (NIPAAm), a sorbent that oozes water when raised above a certain temperature, could potentially replace traditional desiccants in dehumidifiers. The heat of regeneration for NIPAAm consists of some sensible heat to bring the sorbent to the regeneration temperature, plus some latent heat to offset any liquid water that is evaporated as it is exuded from the NIPAAm. This means the NIPAAm regeneration heat has the potential to be much lower than that of a traditional desiccant.
Models were created for a standard vapor compression air conditioning system, two desiccant systems, and two theoretical NIPAAm systems. All components were modeled for simplified steady state operation. For a moderate percent of water evaporated during regeneration, it was found that the NIPAAm systems perform better than standard vapor compression. When compared to the desiccant systems, the NIPAAm systems performed better at almost all percent evaporation values. The regeneration heat was modeled as if supplied by an electric heater. If a cheaper heat source were utilized, the case for NIPAAm would be even stronger.
Future work on NIPAAm dehumidification should focus on lowering the percent evaporation from the 67% value found in literature. Additionally, the NIPAAm cannot exceed the lower critical solution temperature during dehumidification, indicating that a NIPAAm dehumidification system should be carefully designed such that the sorbent temperature is kept sufficiently low during dehumidification.
To improve performance, some systems dehumidify the air before cooling. One common dehumidifier is the desiccant wheel, in which solid desiccant absorbs moisture out of the air while rotating through circular housing. This system improves performance, especially when the desiccant is regenerated with waste or solar heat; however, the heat of regeneration is very large, as the water absorbed during dehumidification must be evaporated. N-isopropylacrylamide (NIPAAm), a sorbent that oozes water when raised above a certain temperature, could potentially replace traditional desiccants in dehumidifiers. The heat of regeneration for NIPAAm consists of some sensible heat to bring the sorbent to the regeneration temperature, plus some latent heat to offset any liquid water that is evaporated as it is exuded from the NIPAAm. This means the NIPAAm regeneration heat has the potential to be much lower than that of a traditional desiccant.
Models were created for a standard vapor compression air conditioning system, two desiccant systems, and two theoretical NIPAAm systems. All components were modeled for simplified steady state operation. For a moderate percent of water evaporated during regeneration, it was found that the NIPAAm systems perform better than standard vapor compression. When compared to the desiccant systems, the NIPAAm systems performed better at almost all percent evaporation values. The regeneration heat was modeled as if supplied by an electric heater. If a cheaper heat source were utilized, the case for NIPAAm would be even stronger.
Future work on NIPAAm dehumidification should focus on lowering the percent evaporation from the 67% value found in literature. Additionally, the NIPAAm cannot exceed the lower critical solution temperature during dehumidification, indicating that a NIPAAm dehumidification system should be carefully designed such that the sorbent temperature is kept sufficiently low during dehumidification.
ContributorsKocher, Jordan Daniel (Author) / Wang, Robert (Thesis advisor) / Phelan, Patrick (Committee member) / Parrish, Kristen (Committee member) / Arizona State University (Publisher)
Created2019
Description
Soft polymer composites with improved thermal conductivity are needed for the thermal management of electronics. Interfacial thermal boundary resistance, however, prevents the efficient use of many high thermal conductivity fill materials. Magnetic alignment of ferrous fill material enforces percolation of the high thermal conductivity fill, thereby shifting the governing boundary resistance to the particle- particle interfaces and increasing the directional thermal conductivity of the polymer composite. Magnetic alignment maximizes the thermal conductivity while minimizing composite stiffening at a fill fraction of half the maximum packing factor. The directional thermal conductivity of the composite is improved by more than 2-fold. Particle-particle contact engineering is then introduced to decrease the particle- particle boundary resistance and further improve the thermal conductivity of the composite.
The interface between rigid fill particles is a point contact with very little interfacial area connecting them. Silver and gallium-based liquid metal (LM) coatings provide soft interfaces that, under pressure, increase the interfacial area between particles and decrease the particle-particle boundary resistance. These engineered contacts are investigated both in and out of the polymer matrix and with and without magnetic alignment of the fill. Magnetically aligned in the polymer matrix, 350nm- thick silver coatings on nickel particles produce a 1.8-fold increase in composite thermal conductivity over the aligned bare-nickel composites. The LM coatings provide similar enhancements, but require higher volumes of LM to do so. This is due to the rapid formation of gallium oxide, which introduces additional thermal boundaries and decreases the benefit of the LM coatings.
The oxide shell of LM droplets (LMDs) can be ruptured using pressure. The pressure needed to rupture LMDs matches closely to thin-walled pressure vessel theory. Furthermore, the addition of tungsten particles stabilizes the mixture for use at higher pressures. Finally, thiols and hydrochloric acid weaken the oxide shell and boost the thermal performance of the beds of LMDs by 50% at pressures much lower than 1 megapascal (MPa) to make them more suitable for use in TIMs.
The interface between rigid fill particles is a point contact with very little interfacial area connecting them. Silver and gallium-based liquid metal (LM) coatings provide soft interfaces that, under pressure, increase the interfacial area between particles and decrease the particle-particle boundary resistance. These engineered contacts are investigated both in and out of the polymer matrix and with and without magnetic alignment of the fill. Magnetically aligned in the polymer matrix, 350nm- thick silver coatings on nickel particles produce a 1.8-fold increase in composite thermal conductivity over the aligned bare-nickel composites. The LM coatings provide similar enhancements, but require higher volumes of LM to do so. This is due to the rapid formation of gallium oxide, which introduces additional thermal boundaries and decreases the benefit of the LM coatings.
The oxide shell of LM droplets (LMDs) can be ruptured using pressure. The pressure needed to rupture LMDs matches closely to thin-walled pressure vessel theory. Furthermore, the addition of tungsten particles stabilizes the mixture for use at higher pressures. Finally, thiols and hydrochloric acid weaken the oxide shell and boost the thermal performance of the beds of LMDs by 50% at pressures much lower than 1 megapascal (MPa) to make them more suitable for use in TIMs.
ContributorsRalphs, Matthew (Author) / Rykaczewski, Konrad (Thesis advisor) / Wang, Robert Y (Thesis advisor) / Phelan, Patrick (Committee member) / Wang, Liping (Committee member) / Devasenathipathy, Shankar (Committee member) / Arizona State University (Publisher)
Created2019
Description
The traditional understanding of robotics includes mechanisms of rigid structures, which can manipulate surrounding objects, taking advantage of mechanical actuators such as motors and servomechanisms. Although these methods provide the underlying fundamental concepts behind much of modern technological infrastructure, in fields such as manufacturing, automation, and biomedical application, the robotic structures formed by rigid axels on mechanical actuators lack the delicate differential sensors and actuators associated with known biological systems. The rigid structures of traditional robotics also inhibit the use of simple mechanisms in congested and/or fragile environments. By observing a variety of biological systems, it is shown that nature models its structures over millions of years of evolution into a combination of soft structures and rigid skeletal interior supports. Through technological bio-inspired designs, researchers hope to mimic some of the complex behaviors of biological mechanisms using pneumatic actuators coupled with highly compliant materials that exhibit relatively large reversible elastic strain. This paper begins the brief history of soft robotics, the various classifications of pneumatic fluid systems, the associated difficulties that arise with the unpredictable nature of fluid reactions, the methods of pneumatic actuators in use today, the current industrial applications of soft robotics, and focuses in large on the construction of a universally adaptable soft robotic gripper and material application tool. The central objective of this experiment is to compatibly pair traditional rigid robotics with the emerging technologies of sort robotic actuators. This will be done by combining a traditional rigid robotic arm with a soft robotic manipulator bladder for the purposes of object manipulation and excavation of extreme environments.
ContributorsShuster, Eden S. (Author) / Thanga, Jekan (Thesis director) / Asphaug, Erik (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
The energy crisis in the past decades has greatly boosted the search for alternatives to traditional fossil foils, and solar energy stands out as an important candidate due to its cleanness and abundance. However, the relatively low conversion efficiency and energy density strongly hinder the utilization of solar energy in wider applications. This thesis focuses on employing metamaterials and metafilms to enhance the conversion efficiency of solar thermal, solar thermophotovoltaic (STPV) and photovoltaic systems.
A selective metamaterial solar absorber is designed in this thesis to maximize the absorbed solar energy and minimize heat dissipation through thermal radiation. The theoretically designed metamaterial solar absorber exhibits absorptance higher than 95% in the solar spectrum but shows emittance less than 4% in the IR regime. This metamaterial solar absorber is further experimentally fabricated and optically characterized. Moreover, a metafilm selective absorber with stability up to 600oC is introduced, which exhibits solar absorptance higher than 90% and IR emittance less than 10%.
Solar thermophotovoltaic energy conversion enhanced by metamaterial absorbers and emitters is theoretically investigated in this thesis. The STPV system employing selective metamaterial absorber and emitter is investigated in this work, showing its conversion efficiency between 8% and 10% with concentration factor varying between 20 and 200. This conversion efficiency is remarkably enhanced compared with the conversion efficiency for STPV system employing black surfaces (<2.5%).
Moreover, plasmonic light trapping in ultra-thin solar cells employing concave grating nanostructures is discussed in this thesis. The plasmonic light trapping inside an ultrathin GaAs layer in the film-coupled metamaterial structure is numerically demonstrated. By exciting plasmonic resonances inside this structure, the short-circuit current density for the film-coupled metamaterial solar cell is three times the short-circuit current for a free-standing GaAs layer.
The dissertation is concluded by discussing about the future work on selective solar thermal absorbers, STPV/TPV systems and light trapping structures. Possibilities to design and fabricate solar thermal absorber with better thermal stability will be discussed, the experimental work of TPV system will be conducted, and the light trapping in organic and perovskite solar cells will be looked into.
A selective metamaterial solar absorber is designed in this thesis to maximize the absorbed solar energy and minimize heat dissipation through thermal radiation. The theoretically designed metamaterial solar absorber exhibits absorptance higher than 95% in the solar spectrum but shows emittance less than 4% in the IR regime. This metamaterial solar absorber is further experimentally fabricated and optically characterized. Moreover, a metafilm selective absorber with stability up to 600oC is introduced, which exhibits solar absorptance higher than 90% and IR emittance less than 10%.
Solar thermophotovoltaic energy conversion enhanced by metamaterial absorbers and emitters is theoretically investigated in this thesis. The STPV system employing selective metamaterial absorber and emitter is investigated in this work, showing its conversion efficiency between 8% and 10% with concentration factor varying between 20 and 200. This conversion efficiency is remarkably enhanced compared with the conversion efficiency for STPV system employing black surfaces (<2.5%).
Moreover, plasmonic light trapping in ultra-thin solar cells employing concave grating nanostructures is discussed in this thesis. The plasmonic light trapping inside an ultrathin GaAs layer in the film-coupled metamaterial structure is numerically demonstrated. By exciting plasmonic resonances inside this structure, the short-circuit current density for the film-coupled metamaterial solar cell is three times the short-circuit current for a free-standing GaAs layer.
The dissertation is concluded by discussing about the future work on selective solar thermal absorbers, STPV/TPV systems and light trapping structures. Possibilities to design and fabricate solar thermal absorber with better thermal stability will be discussed, the experimental work of TPV system will be conducted, and the light trapping in organic and perovskite solar cells will be looked into.
ContributorsWang, Hao (Author) / Wang, Liping (Thesis advisor) / Phelan, Patrick (Committee member) / Wang, Robert (Committee member) / Dai, Lenore (Committee member) / Rykaczewski, Konrad (Committee member) / Arizona State University (Publisher)
Created2016
Description
“Smart” materials are used for a broad range of application including electronics, bio-medical devices, and smart clothing. This work focuses on development of smart self-sealing and breathable protective gear for soldiers against Chemical Weapon Agents (CWA). Specifically, the response of chemo-mechanical swelling polymer modified meshes to contact with stimuli droplets was studied. Theoretical discussion of the mechanism of smart materials is followed by development and experimental analysis of different modified mesh designs. A multi-physics model is proposed based on experimental data and the prototype of the fabric is tested in aerosol impingement conditions to confirm the barrier formed by rapid-self-sealing feature of the design.
ContributorsUppal, Aastha (Author) / Rykaczewski, Konrad (Thesis advisor) / Hildreth, Owen (Committee member) / Marvi, Hamidreza (Committee member) / Arizona State University (Publisher)
Created2016
Description
It is well known that the geckos can cling to almost any surface using highly dense micro
ano fibrils found on the feet that rely on Van Der Waals forces to adhere. A few experimental and theoretical approaches have been taken to understand the adhesion mechanism of gecko feet. This work explains the building procedure of custom experimental setup to test the adhesion force over a temperature range and extends its application in space environment, potentially unsafe working condition.
This study demonstrates that these adhesive capable of switching adhesive properties not only at room environment but also over a temperature range of -160 degC to 120 degC in vacuum conditions. These conditions are similar to the condition experienced by a satellite in a space orbiting around the earth. Also, this study demonstrated various detachment and specimen patch preparation methods. The custom-made experimental setup for adhesion test can measure adhesion force in temperature and pressure controlled environment over specimen size of 1 sq. inch. A cryogenic cooling system with liquid nitrogen is used to achieve -160 degC and an electric resistive heating system are used to achieve 120 degC in controlled volume. Thermal electrodes, infrared thermopile detectors are used to record temperature at sample and pressure indicator to record vacuum condition in controlled volume. Reversibility of the switching behaviour of the specimen in controlled environment confirms its application in space and very high or very low-temperature conditions.
The experimental setup was developed using SolidWorks as a design tool, Ansys as simulation tool and the data acquisition utilizes LabVIEW available in the market today.
ano fibrils found on the feet that rely on Van Der Waals forces to adhere. A few experimental and theoretical approaches have been taken to understand the adhesion mechanism of gecko feet. This work explains the building procedure of custom experimental setup to test the adhesion force over a temperature range and extends its application in space environment, potentially unsafe working condition.
This study demonstrates that these adhesive capable of switching adhesive properties not only at room environment but also over a temperature range of -160 degC to 120 degC in vacuum conditions. These conditions are similar to the condition experienced by a satellite in a space orbiting around the earth. Also, this study demonstrated various detachment and specimen patch preparation methods. The custom-made experimental setup for adhesion test can measure adhesion force in temperature and pressure controlled environment over specimen size of 1 sq. inch. A cryogenic cooling system with liquid nitrogen is used to achieve -160 degC and an electric resistive heating system are used to achieve 120 degC in controlled volume. Thermal electrodes, infrared thermopile detectors are used to record temperature at sample and pressure indicator to record vacuum condition in controlled volume. Reversibility of the switching behaviour of the specimen in controlled environment confirms its application in space and very high or very low-temperature conditions.
The experimental setup was developed using SolidWorks as a design tool, Ansys as simulation tool and the data acquisition utilizes LabVIEW available in the market today.
ContributorsMate, Sunil (Author) / Marvi, Hamidreza (Thesis advisor) / Rykaczewski, Konrad (Committee member) / Lee, Hyunglae (Committee member) / Arizona State University (Publisher)
Created2016
Description
This paper details ink chemistries and processes to fabricate passive microfluidic devices using drop-on-demand printing of tetraethyl-orthosilicate (TEOS) inks. Parameters space investigation of the relationship between printed morphology and ink chemistries and printing parameters was conducted to demonstrate that morphology can be controlled by adjusting solvents selection, TEOS concentration, substrate temperature, and hydrolysis time. Optical microscope and scanning electron microscope images were gathered to observe printed morphology and optical videos were taken to quantify the impact of morphology on fluid flow rates. The microscopy images show that by controlling the hydrolysis time of TEOS, dilution solvents and the printing temperature, dense or fracture structure can be obtained. Fracture structures are used as passive fluidic device due to strong capillary action in cracks. At last, flow rate of passive fluidic devices with different thickness printed at different temperatures are measured and compared. The result shows the flow rate increases with the increase of device width and thickness. By controlling the morphology and dimensions of printed structure, passive microfluidic devices with designed flow rate and low fluorescence background are able to be printed.
ContributorsHuang, Yiwen (Author) / Hildreth, Owen (Thesis advisor) / Wang, Robert (Committee member) / Rykaczewski, Konrad (Committee member) / Arizona State University (Publisher)
Created2016
Description
Analytical solution of the pressure field for water uptake through a composite root, coupled with fully saturated soil is derived by using the slender body approximation. It is shown that in general, the resistance of the root and soil are not additive. This result can play a very important role in modelling water uptake through plant roots and determination of hydraulic resistances of plant roots. Optimum plant root structure that minimizes a single root’s hydraulic resistance is also studied in this work with the constraint of prescribed root volume. Hydraulic resistances under the slender body approximation and without such a limitation are considered. It is found that for large stele-to-cortex permeability ratio, there exists an optimum root length-to-base-radius ratio that minimizes the hydraulic resistance. A remarkable feature of the optimum root structure is that the optimum dimensionless stele conductivity depends only on a single geometrical parameter, the stele-to-root base-radius ratio. Once the stele-to-root base-radius ratio and the stele-to-cortex permeability ratio are given, the optimum root length-to-radius ratio can be found. While these findings remain to be verified by experiments for real plant roots, they offer theoretical guidance for the design of bio-inspired structures that minimizes hydraulic resistance for fluid production from porous media.
ContributorsChandrashekar, Sriram (Author) / Chen, Kang-Ping (Thesis advisor) / Huang, Huei-Ping (Committee member) / Rykaczewski, Konrad (Committee member) / Arizona State University (Publisher)
Created2016