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Thinking intuitively: the rich (and at times illogical) world of concepts
Intuitive knowledge of the world involves knowing what kinds of things have which properties. We express it in generalities such as “ducks lay eggs”. It contrasts with extensional knowledge about actual individuals in the world, which we express in quantified statements such as “All US Presidents are male”. Reasoning based on this intuitive knowledge, while highly fluent and plausible may in fact lead us into logical fallacy. Several lines of research point to our conceptual memory as the source of this logical failure. We represent concepts with prototypical properties, judging likelihood and argument strength on the basis of similarity between ideas. Evidence that our minds represent the world in this intuitive way can be seen in a range of phenomena, including how people interpret logical connectives applied to everyday concepts, studies of creativity and emergence in conceptual combination, and demonstrations of the logically inconsistent beliefs that people express in their everyday language
Space shuttle main engine hardware simulation
The Huntsville Simulation Laboratory (HSL) provides a simulation facility to test and verify the space shuttle main engine (SSME) avionics and software system using a maximum complement of flight type hardware. The HSL permits evaluations and analyses of the SSME avionics hardware, software, control system, and mathematical models. The laboratory has performed a wide spectrum of tests and verified operational procedures to ensure system component compatibility under all operating conditions. It is a test bed for integration of hardware/software/hydraulics. The HSL is and has been an invaluable tool in the design and development of the SSME
Lifting of D1-D5-P states
We consider states of the D1-D5 CFT where only the left-moving sector is
excited. As we deform away from the orbifold point, some of these states will
remain BPS while others can `lift'. We compute this lifting for a particular
family of D1-D5-P states, at second order in the deformation off the orbifold
point. We note that the maximally twisted sector of the CFT is special: the
covering surface appearing in the correlator can only be genus one while for
other sectors there is always a genus zero contribution. We use the results to
argue that fuzzball configurations should be studied for the full class
including both extremal and near-extremal states; many extremal configurations
may be best seen as special limits of near extremal configurations.Comment: 51 pages, 6 figure
Impregnation and Adsorption of Rare Earth Elements on Amberlite XAD-7
Beads were washed then impregnated with an organophosphorous extractant D2EHPA. The washing process, as well as factors in the impregnation process were studied. Water was deemed sufficient to prewash the beads before use over small and large amounts of acid with acetone. The impregnation of beads at an Amberlite D2EHPA ratio of 1:1 was determined to be best. Absorption isotherms of Neodymium were the first to be studied. By testing different concentrations, Amberlite was determined to absorb the max amount at 4000 ppm. The pH values from 2-7 were determined to have no effect on the amount of Neodymium absorbed by Amberlite. The pH values 0 and 1 were not able to be measured by the ICP; possibly due to the large number of ions in the solution. The shaking time of Amberlite to adsorb Neodymium was determined to be over 15 hours. It is recommended to shake Amberlite with the Rare Earth solution overnight. The adsorption isotherm of Lanthanum was also tested and determined to be similar to Neodymium. When a Lanthanum and Neodymium solution was created, the isotherm showed that Neodymium adsorbed much better than Lanthanum. The elution of Neodymium from Amberlite was also achieved and the Amberlite was reloaded successfully with Neodymium
Lateral-Torsional Instability and Biaxial Flexure of Continuous GFRP Beams Including Warping and Shear Deformations
This dissertation presents an experimental and theoretical study of the lateral-torsional instability and biaxial flexure of Glass Fiber Reinforced Polymer (GFRP) beams including warping and shear deformation effects. The theoretical analysis is based on three simultaneous differential equations of equilibrium with new terms added to account for shear deformation effects. To solve these equations, algorithms based upon a central finite-difference approach are then developed. The experimental study is conducted on a series of single- and multi-span beams subjected to concentrated loads. The predicted beam behavior agreed well with that observed experimentally. The investigation revealed that the ASCE-LRFD Prestandard for pultruded GFRP beams can result in seriously unconservative buckling load predictions. The same is found for biaxially loaded beams which can develop very large induced warping normal stresses currently unaccounted for by the ACSE-LRFD Prestandard. A new lateral-torsional buckling load equation is presented which accounts for shear deformation effects
Forage Seed Quality: Dormancy, Standards and Quarantine
There are many dimensions to the concept of seed quality. Viable seed which will not germinate when provided with all the requirements for germination is dormant. Forage grasses mostly exhibit non-deep physiological dormancy (PD), while physical dormancy (PY) is common in forage legumes where imbibition is prevented by the seed coat’s impermeability to water (hard seed). Methods for breaking PD and PY to allow germination testing and/or crop establishment are discussed.
In the seed industry seed quality standards are an important feature of quality assurance and may apply for seed production contracts, seed certification, seed sale and seed importing. Standards for these uses are discussed, with a comment on legislated minimum germination standards which may do little to offer protection to the buyer. Exported seed lots must meet the seed quality standards and phytosanitory/biosecurity requirements of the importing country, but while there is an obvious need to protect against the spread of economically important pests, they should not be used as unnecessary barriers to the seed trade
The Guppy Effect as Interference
People use conjunctions and disjunctions of concepts in ways that violate the
rules of classical logic, such as the law of compositionality. Specifically,
they overextend conjunctions of concepts, a phenomenon referred to as the Guppy
Effect. We build on previous efforts to develop a quantum model that explains
the Guppy Effect in terms of interference. Using a well-studied data set with
16 exemplars that exhibit the Guppy Effect, we developed a 17-dimensional
complex Hilbert space H that models the data and demonstrates the relationship
between overextension and interference. We view the interference effect as, not
a logical fallacy on the conjunction, but a signal that out of the two
constituent concepts, a new concept has emerged.Comment: 10 page
Chandra observations of the HII complex G5.89-0.39 and TeV gamma-ray source HESSJ1800-240B
We present the results of our investigation, using a Chandra X-ray
observation, into the stellar population of the massive star formation region
G5.89-0.39, and its potential connection to the coincident TeV gamma-ray source
HESSJ1800-240B. G5.89-0.39 comprises two separate HII regions G5.89-0.39A and
G5.89-0.39B (an ultra-compact HII region). We identified 159 individual X-ray
point sources in our observation using the source detection algorithm
\texttt{wavdetect}. 35 X-ray sources are associated with the HII complex
G5.89-0.39. The 35 X-ray sources represent an average unabsorbed luminosity
(0.3-10\,keV) of \,erg/s, typical of B7-B5 type stars. The
potential ionising source of G5.89-0.39B known as Feldt's star is possibly
identified in our observation with an unabsorbed X-ray luminosity suggestive of
a B7-B5 star. The stacked energy spectra of these sources is well-fitted with a
single thermal plasma APEC model with kT5\,keV, and column density
N\,cm (A). The residual
(source-subtracted) X-ray emission towards G5.89-0.39A and B is about 30\% and
25\% larger than their respective stacked source luminosities. Assuming this
residual emission is from unresolved stellar sources, the total
B-type-equivalent stellar content in G5.89-0.39A and B would be 75 stars,
consistent with an earlier estimate of the total stellar mass of hot stars in
G5.89-0.39. We have also looked at the variability of the 35 X-ray sources in
G5.89-0.39. Ten of these sources are flagged as being variable. Further studies
are needed to determine the exact causes of the variability, however the
variability could point towards pre-main sequence stars. Such a stellar
population could provide sufficient kinetic energy to account for a part of the
GeV to TeV gamma-ray emission in the source HESSJ1800-240B.Comment: 34 pages, 9 figure
Experimental Evidence for Quantum Structure in Cognition
We proof a theorem that shows that a collection of experimental data of
membership weights of items with respect to a pair of concepts and its
conjunction cannot be modeled within a classical measure theoretic weight
structure in case the experimental data contain the effect called
overextension. Since the effect of overextension, analogue to the well-known
guppy effect for concept combinations, is abundant in all experiments testing
weights of items with respect to pairs of concepts and their conjunctions, our
theorem constitutes a no-go theorem for classical measure structure for common
data of membership weights of items with respect to concepts and their
combinations. We put forward a simple geometric criterion that reveals the non
classicality of the membership weight structure and use experimentally measured
membership weights estimated by subjects in experiments to illustrate our
geometrical criterion. The violation of the classical weight structure is
similar to the violation of the well-known Bell inequalities studied in quantum
mechanics, and hence suggests that the quantum formalism and hence the modeling
by quantum membership weights can accomplish what classical membership weights
cannot do.Comment: 12 pages, 3 figure
Developing a Challenging Online Doctoral Course Using Backward and Three-Phase Design Models
Current Practices and Future Trends in Aviation (DAV 735)—one of 19 online courses in the Ph.D. in Aviation program at Embry-Riddle Aeronautical University—has run five times since 2011. A team of one instructional designer and one professor were responsible for its initial design, development, and ongoing improvement. This continuity provided the opportunity for a longitudinal, descriptive case study reporting on three wicked instructional design challenges: (a) doctoral student body comprised largely of multidisciplinary aviation professionals, (b) no seminal textbook on the course topics, and (c) unforeseen usability problems with Internet technologies. This case analysis has significance because of the lack of literature reporting on the practices of instructional design teams in terms of how theories are applied. An adapted three-phase design model and the backward design model informed the initial design and ongoing improvement of the course. This approach was successful in addressing needs of the users and was instrumental in the course receiving a Blackboard® Catalyst Exemplary Course award in 2014. Recommendations include: (a) adopting an iterative and collaborative course development and improvement process, (b) using problem-based learning, and (c) empowering students to both define and enhance their learning. Use of a template-based production process, reliance on post-course perceptions to inform major improvements, and lack of generalizability when student enrollments or feedback are limited led to questions as to whether the models need to be extended or elaborated
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