Papers by Michael Holloway
Cornell University - arXiv, Feb 23, 2016
The purpose of this paper is to investigate the duality between large scale and small scale. It i... more The purpose of this paper is to investigate the duality between large scale and small scale. It is done by creating a connection between C*-algebras and scale structures. In the commutative case we consider C*-subalgebras of C b (X), the C*-algebra of bounded complexvalued functions on X. Namely, each C*-subalgebra C of C b (X) induces both a small scale structure on X and a large scale structure on X. The small scale structure induced on X corresponds (or is analogous) to the restriction of C b (h(X)) to X, where h(X) is the Higson compactification. The large scale structure induced on X is a generalization of the C 0-coarse structure of N.Wright. Conversely, each small scale structure on X induces a C*-subalgebra of C b (X) and each large scale structure on X induces a C*-subalgebra of C b (X). To accomplish the full correspondence between scale structures on X and C*-subalgebras of C b (X) we need to enhance the scale structures to what we call hybrid structures. In the noncommutative case we consider C*-subalgebras of bounded operators B(l 2 (X)).
2022 IEEE Aerospace Conference (AERO)
Journal of System Safety
While software in industries such as aviation has a good safety record, little is known about whe... more While software in industries such as aviation has a good safety record, little is known about whether standards for software in other safety-critical applications “work” — or even what that means. Safe use of software in safety-critical applications requires well-founded means of determining whether the software is fit for such use. It is often implicitly argued that software is fit for safety-critical use because it conforms to an appropriate standard. Without knowing whether a standard “works,” such reliance is an experiment and without carefully collecting assessment data, that experiment is unplanned. To help “plan” the experiment, we organized a workshop to develop practical ideas for assessing software safety standards. In this paper, we relate and elaborate on our workshop discussion, which revealed subtle, but important, study design considerations and practical barriers to collecting appropriate historical data and recruiting appropriate experimental subjects. We discuss as...
We present a concept for using RF-based acceleration of nanoparticles (NPs) as a means of generat... more We present a concept for using RF-based acceleration of nanoparticles (NPs) as a means of generating thrust for future space missions: the Kinetic Acceleration Resource Vector Engine (KARVE) thruster. Acceleration of nanoparticles (NPs) via DC accelerators has been shown to be feasible in dust accelerator labs such as the Heidelberg dust accelerator and the 3 MV hypervelocity dust accelerator at the Colorado Center for Lunar Dust and Atmospheric Studies. In contrast, KARVE uses RF-driven acceleration of nanoparticles as the basis of a thruster design lying between chemical and ion engines in performance: more efficient than chemical engines in terms of specific impulse; and higher thrust than ion engines. The properties of multi-gap RF accelerators also allow an on-the-fly tradeoff between specific impulse and thrust.
Hypersonic vehicles operate at speeds in excess of Mach 5, producing extreme temperatures and non... more Hypersonic vehicles operate at speeds in excess of Mach 5, producing extreme temperatures and nonequilibrium flow phenomena. A principle challenge associated with designing hypersonic platforms lies in the modeling of the nonequilibrium environment in which they will operate. The overall goal of this thesis is to perform a detailed investigation into the thermochemistry modeling of hypersonic air flows and is broken into two main sections. The first section provides an assessment of different assumptions for thermochemistry modeling on hypersonic air flows. A computational analysis is used to study flows over a double-cone using three different thermochemical approaches: nonequilibrium flow, equilibrium flow, and frozen flow for air at several different freestream conditions. The thermochemical model effects on the flow field and surface properties are specific areas of interest. The resulting aerothermodynamic loads are compared to experiments performed in the CUBRC LENS-I and LENS...
Hydraulic Fracturing and Well Stimulation, 2019
DRIVEN ACCELERATORS D.C. Nguyen , C.E. Buechler, G.E. Dale, R.L. Fleming, M.A. Holloway, J.W. Lew... more DRIVEN ACCELERATORS D.C. Nguyen , C.E. Buechler, G.E. Dale, R.L. Fleming, M.A. Holloway, J.W. Lewellen, D. Patrick Los Alamos National Laboratory J. Neilson, V. Dolgashev, E.N. Jongewaard, E.A. Nanni, A. Sy and S. Tantawi SLAC National Accelerator Laboratory Abstract Small, lightweight, few-MeV electron accelerators that can operate with low-voltage power sources, e.g., solidstate transistors running on 50 VDC, instead of highvoltage klystrons, will provide a new tool to enhance existing applications of accelerators as well as to initiate new ones. Recent advances in gallium nitride (GaN) semiconductor technologies [1] have resulted in a new class of high-power RF solid-state devices called highelectron mobility transistors (HEMTs). These HEMTs are capable of generating a few hundred watts at S-, Cand X-bands at 10% duty factor. We have characterized a number of GaN HEMTs and verified they have suitable RF characteristics to power accelerator cavities. We have measured energy gain a...
The Digital Peepholes project is part of the Chicago-Kent Privacy program at IIT Chicago-Kent Col... more The Digital Peepholes project is part of the Chicago-Kent Privacy program at IIT Chicago-Kent College of Law. CK Privacy provides an opportunity for students, faculty members, policymakers and the public to assess the ways in which technologies present new challenges to privacy and data protection, as well as to develop technical and legal ways to better ensure privacy and improve data protection.
Los Alamos National Laboratory, in collaboration with SLAC and Goddard Space Flight Center, have ... more Los Alamos National Laboratory, in collaboration with SLAC and Goddard Space Flight Center, have begun developing a high-duty-factor, MeV-range linear accelerator intended for use on satellites, specifically to probe the magnetosphere-ionosphere linkage. The design makes use of C-band cavities operating at moderate gradients, individually powered by 500 W RF amplifier chips. We present the results of technology maturation efforts including RF amplifier performance studies, cavity tuner design and an initial acceleration test using a DC beam source and single RF cavity.
2021 IEEE/AIAA 40th Digital Avionics Systems Conference (DASC), 2021
The Overarching Properties (OPs) have been created by an international working group and are bein... more The Overarching Properties (OPs) have been created by an international working group and are being evaluated by the National Aeronautics and Space Administration (NASA), the Federal Aviation Administration (FAA), industry, and other certifying agencies in an effort to streamline certification processes. Their intent is to facilitate the use of alternative approaches and to allow flexibility to combine the system, software, and complex hardware certification. The hope is that the FAA may eventually establish an Advisory Circular that offers the OPs as a Means of Compliance (MoC) for software approval (and eventually systems and hardware) by showing the product possesses the three OPs: Intent (specification of the intended behavior), Correctness (implementation of the intended behavior) and Innocuity (safety of unintended behavior). In the certification community, there is still a concern about the practicability of using such high level properties in certification. This paper aims to address that concern by showing possession of the OPs in an industrial case study using assurance arguments. The two main contributions of this paper are: a certification process based on OPs as Means of Compliance, and a certification argument for an on-board physical model of an UAV (Unmanned Aerial Vehicle), as industrial example. We propose a hybrid approach for the certification process that combines OPs with existing certification standards. Thus, OPs can be used for parts of a system that uses technologies that are not supported by current standards or for which existing standards require additional effort without commensurate additional safety assurance.
M/C Journal, 2006
The Internet has connected people and cultures in a way that, just ten years ago, was unimaginabl... more The Internet has connected people and cultures in a way that, just ten years ago, was unimaginable. Because of the net, materials once scarce are now ubiquitous. Indeed, never before in human history have so many people had so much access to such a wide variety of cultural material, yet far from heralding a new cultural nirvana, we are facing a creative lock-down. Over the last hundred years, copyright term has been extended time and again by a creative industry eager to hold on to the exclusive rights to its most lucrative materials. Previously, these rights guaranteed a steady income because the industry controlled supply and, in many cases, manufactured demand. But now culture has moved from being physical artefacts that can be sold or performances that can be experienced to being collections of 1s and 0s that can be easily copied and exchanged. People are revelling in the opportunity to acquire and experience music, movies, TV, books, photos, essays and other materials that they...
Mutation Research/Genetic Toxicology, 1987
The environmental contaminants pyrene, 1-nitropyrene, 1,8-dinitropyrene, fluoranthene, and 3-nitr... more The environmental contaminants pyrene, 1-nitropyrene, 1,8-dinitropyrene, fluoranthene, and 3-nitrofluoranthene were exposed to light (greater than or equal to 310 nm) either in DMSO, or following coating onto silica. Under all conditions tested the pyrenyl were less stable than the fluoranthenyl compounds. During irradiation in DMSO or on silica, 1-nitropyrene had half-lives of 1.2 and 6 days, while those of 3-nitrofluoranthene were 12.5 and greater than 20 days, respectively. The photodecomposition of 1,8-dinitropyrene resembled that of 1-nitropyrene with half-lives of 0.7 and 5.7 days. A principle photodecomposition product of 1,8-dinitropyrene was identified as 1-nitropyren-8-ol. It was also found that when the nitroarenes were exposed to light, the loss of compound was associated with a concomitant loss of mutagenicity in Salmonella typhimurium strain TA98. The mechanism of nitrated polycyclic aromatic hydrocarbon decomposition and 1-nitropyren-8-ol formation, and the relevance to the atmospheric disposition of these compounds are discussed.
Neuropsychologia, 2017
There has been great interest in characterizing the response of the amygdala to emotional faces, ... more There has been great interest in characterizing the response of the amygdala to emotional faces, especially in the context of social cognition. Although amygdala activation is most often associated with fearful or angry stimuli, there is considerable evidence that the response of the amygdala to neutral faces is both robust and reliable. This characteristic of amygdala function is of particular interest in the context of assessing populations with executive function deficits, such as traumatic brain injuries, which can be evaluated using fMRI attention modulation tasks that evaluate prefrontal control over representations, notably faces. The current study tested the hypothesis that the amygdala may serve as a marker of selective attention to neutral faces. Using fMRI, we gathered data within a chronic traumatic brain injury population. Blood Oxygenation Level Dependent (BOLD) signal change within the left and right amygdalae and fusiform face areas was measured while participants viewed neutral faces and scenes, under conditions requiring participants to (1) categorize pictures of faces and scenes, (2) selectively attend to either faces or scenes, or (3) attend to both faces and scenes. Findings revealed that the amygdala is an effective marker for selective attention to neutral faces and, furthermore, it was more face-specific than the fusiform face area.
Journal of Sustainable Energy Engineering, 2013
Abstract Hydraulic fracturing (also known as fracking, fracing, and other variations) of rock dee... more Abstract Hydraulic fracturing (also known as fracking, fracing, and other variations) of rock deep beneath the Earth’s surface to release petroleum product has become a contentious subject across the globe. This practice is not to be confused with drilling or extraction. Fracing is the process of using fluid power to fracture rock to release gas and sometimes crude oil. It is not drilling, although drilling must be done to establish a well in order to pump fluid thus fracturing rock to release product. Certain countries have actually outlawed the practice of hydraulic fracturing claiming that ground water and air pollution increase due to the practice. There is also the claim that the comfort of life is adversely affected. Legitimate concerns are always available and examples to purport a concerned view are magnified, in the authors’ opinion. The intent of this paper is to provide a correct and balanced view of fracturing underground rock with fluids in order to release a product to produce energy. The concept of using water to do work is nothing new. Pumping fluid below ground in order to fracture rock to release gaseous petroleum is, however, a relatively new practice. It is done with surprising precision as well as environmental concern yet it is interesting how the public reacts to the practice in relation to other techniques used throughout the world. This paper will explore the materials used as well as the concerns most common to the practice.
Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, 1984
A series of nitropyrenes and other nitroarenes were reduced electrochemically with a dropping mer... more A series of nitropyrenes and other nitroarenes were reduced electrochemically with a dropping mercury electrode. The half-wave potentials (E~/2) corresponding to the reduction of the various nitro functions was determined. A linear relationship between Ell 2 and the logarithm of the mutagenicities exhibited by these chemicals in Salmonella typhimurium strains TA98 and TA1538 was demonstrated. A linear relationship between Ell 2 and the calculated energies of the Lowest Unoccupied Molecular Orbital (LUMO) was also established. This indicates that the mutagenicities of nitroarenes can be predicted from calculated LUMO energies.
Cancer Research, 2013
Survivin is a member of the inhibitor of apoptosis protein (IAP) family based on its N-terminal b... more Survivin is a member of the inhibitor of apoptosis protein (IAP) family based on its N-terminal baculovirus IAP repeat (BIR) domain. The protein is largely undetectable in differentiated tissues, but is highly expressed in most human tumors. Its cytoplasmic expression in these tumors correlates with reduced tumor cell death, increased resistance to cancer therapy, and decreased patient survival. Survivin is actively exported into the cytoplasm exclusively by the chromosomal region maintenance 1 (CRM1/Exportin1) protein, one of seven known nuclear export proteins. CRM1 binds to the canonical nuclear export signal (NES) domain within the survivin protein. Inhibition of CRM1-mediated nuclear export has been suggested as a novel cancer therapeutic strategy that restores the tumor suppressor function of multiple nuclear proteins. Here, we investigated the anti-tumor mechanisms of two novel, drug-like CRM1 inhibitors, KPT-185 and KPT-276, in estrogen-receptor positive and triple negative ...
International Oil Spill Conference Proceedings, 2005
This paper describes afield handbook jointly prepared for the New Zealand (NZ) Maritime Safety Au... more This paper describes afield handbook jointly prepared for the New Zealand (NZ) Maritime Safety Authority (MSA) and Australian MSA (AMSA) to help plan the scope, scale, and design of oil spill monitoring programs. A two-class monitoring nomenclature is used to classify monitoring according to its underlying purpose. Type I (Operational) Monitoring: provides information of direct relevance to spill response operations, i.e. information needed to plan or execute response or cleanup strategies. Type II (Scientific) Monitoring: relates to non-response objectives, i.e. short and long term environmental damage assessments (including recovery), purely scientific studies, and all post spill monitoring activities. The two-class monitoring nomenclature recognizes the very different objectives of Type I and Type II monitoring, and the methods, scope, and degree of scientific rigour required for each. These in turn, have a significant bearing on the cost of the monitoring, and who will pay for i...
Uploads
Papers by Michael Holloway