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d-QPSO: A Quantum-Behaved Particle Swarm Technique for Finding D-Optimal Designs With Discrete and Continuous Factors and a Binary Response
Identifying optimal designs for generalized linear models with a binary response can be a challengingtask, especially when there are both discrete and continuous independent factors in the model. Theoreticalresults rarely exist for such models, and for the handful that do, they usually come with restrictive assumptions.In this article, we propose the d-QPSO algorithm, a modified version of quantum-behaved particleswarm optimization, to find a variety of D-optimal approximate and exact designs for experiments withdiscrete and continuous factors and a binary response. We show that the d-QPSO algorithm can efficientlyfind locally D-optimal designs even for experiments with a large number of factors and robust pseudo-Bayesian designs when nominal values for the model parameters are not available. Additionally, we investigaterobustness properties of the d-QPSO algorithm-generated designs to variousmodel assumptions andprovide real applications to design a bio-plastics odor removal experiment, an electronic static experiment,and a 10-factor car refueling experiment. Supplementary materials for the article are available online
The differing magnitude distributions of the two Jupiter Trojan color populations
The Jupiter Trojans are a significant population of minor bodies in the
middle Solar System that have garnered substantial interest in recent years.
Several spectroscopic studies of these objects have revealed notable
bimodalities with respect to near-infrared spectra, infrared albedo, and color,
which suggest the existence of two distinct groups among the Trojan population.
In this paper, we analyze the magnitude distributions of these two groups,
which we refer to as the red and less red color populations. By compiling
spectral and photometric data from several previous works, we show that the
observed bimodalities are self-consistent and categorize 221 of the 842 Trojans
with absolute magnitudes in the range H<12.3 into the two color populations. We
demonstrate that the magnitude distributions of the two color populations are
distinct to a high confidence level (>95%) and fit them individually to a
broken power law, with special attention given to evaluating and correcting for
incompleteness in the Trojan catalog as well as incompleteness in our
categorization of objects. A comparison of the best-fit curves shows that the
faint-end power-law slopes are markedly different for the two color
populations, which indicates that the red and less red Trojans likely formed in
different locations. We propose a few hypotheses for the origin and evolution
of the Trojan population based on the analyzed data.Comment: Published in AJ; 26 pages, 7 figure
Applications of Two Body Dirac Equations to Hadron and Positronium Spectroscopy
We review recent applications of the Two Body Dirac equations of constraint
dynamics to meson spectroscopy and describe new extensions to three-body
problems in their use in the study of baryon spectroscopy. We outline unique
aspects of these equations for QED bound states that distinguish them among the
various other approaches to the relativistic two body problem. Finally we
discuss recent theorectial solutions of new peculiar bound states for
positronium arising from the Two Body Dirac equations of constraint dynamics,
assuming point particles for the electron and the positron.Comment: Invited talk: CST-MISC joint international symposium on particle
physics - From spacetime dynamics to phenomenology - Tokyo, March 15-16, 201
Metabolite-mediated catalyst conversion of PFK and PFP
Metabolites known to occur in the cytosol of photosynthetic leaf cells were found to mediate the reversible conversion of pyrophosphate—D-fructose-6-phosphate 1-phosphotransferase (PFP) to phosphofructokinase (PFK) in partially purified preparations from spinach leaves. Preincubation of PFP with fructose 2,6-bisphosphate, ATP or fructose 6-phosphate converted PFP to PFK. The reverse reaction (PFK → PFP) was promoted by UDP-glucose plus pyrophosphate. These conversions in catalytic capability were accompanied by changes in molecular mass and charge. The results are in accord with the view that the alterations in PFP and PFK activity, provisionally called ‘metabolite-mediated catalyst conversion’, represent a regulatory mechanism to direct left cytosolic carbon flux in either the biosynthetic or degradatory direction
Alternative Epinephrine Auto-Injector
Project: Alternative Epinephrine Injector started as a solution for Bianca Aleman’s little brother however the scope has evolved to include the many millions of individuals across the world who struggle with a life-threatening allergen. The stakeholders of this project are Cal Poly and Dr. Michael D. Whitt. Our goals are the following:
● Develop a foolproof method of injection that consistently delivers a dosage of epinephrine
● Be equal or less than the current size of an EpiPen (6 in)
● Be easy to transport or store when not-in-use
● Create an isolated environment where the epinephrine will not be denatured due to environmental changes (e.g. temperature, light sensitivity, etc.)
● Class II FDA Medical Device ● Deliver a fully functioning prototype of an alternative epinephrine auto-injector
● Stay within a budget of 700
● Do not infringe on Mylan or Kaleo’s current paten
0.7–2.5μm Spectra of Hilda Asteroids
The Hilda asteroids are primitive bodies in resonance with Jupiter whose origin and physical properties are not well understood. Current models posit that these asteroids formed in the outer solar system and were scattered along with the Jupiter Trojans into their present-day positions during a chaotic episode of dynamical restructuring. In order to explore the surface composition of these enigmatic objects in comparison with an analogous study of Trojans, we present new near-infrared spectra (0.7–2.5 μm) of 25 Hilda asteroids. No discernible absorption features are apparent in the data. Synthesizing the bimodalities in optical color and infrared reflectivity reported in previous studies, we classify 26 of the 28 Hildas in our spectral sample into the so-called less-red and red sub-populations and find that the two sub-populations have distinct average spectral shapes. Combining our results with visible spectra, we find that Trojans and Hildas possess similar overall spectral shapes, suggesting that the two minor body populations share a common progenitor population. A more detailed examination reveals that while the red Trojans and Hildas have nearly identical spectra, less-red Hildas are systematically bluer in the visible and redder in the near-infrared than less-red Trojans, indicating a putative broad, shallow absorption feature between 0.5 and 1.0 μm. We argue that the less-red and red objects found in both Hildas and Trojans represent two distinct surface chemistries and attribute the small discrepancy between less-red Hildas and Trojans to the difference in surface temperatures between the two regions
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