cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
title: Cross Approximation Methods for Integral Equation Matrices with Complex Structure
Creators: name: Blackburn, Jordon
Publisher: name: University of Kentucky Libraries
Year: 2021
Subjects: subject: FOS: Electrical engineering, electronic engineering, information engineering
valueUri: http://www.oecd.org/science/inno/38235147.pdf

description: Electrical and computer engineers rely on electromagnetic field (EM) theory to formulate and design systems that utilize information or energy obtained from a signal. Over time these systems have been increased in scale and complexity and adapted to handle a wider array of problems. This has motivated substantial developments in computational sciences including the area of computational electromagnetics (CEM).The focus of CEM is the simulation of electromagnetic fields. At the University of Kentucky, the CEM group has developed several modeling tools that are based on the application of approximation theory to integral equations. This allows the physical problem to be represented as a linear system of equations. Often times, these simulations prove difficult to implement due to issues related to hardware limitations, problem scale, complicated geometries, etc. To deal with large problems that might otherwise exceed the capacity of a computing platform, several sparse sampling methods have been developed. These methods enable the construction of controllably accurate, data-sparse representations of large, dense matrices using only a sparse set of samples of the underlying matrix. One such method is the Adaptive Cross Approximation (ACA) - which is a type of Pseudoskeleton (PSK) method. However, recently it has been observed that the ACA fails to provide adequate error control for certain types of structured, low-rank matrices. In this presentation, we develop modified versions of the ACA and investigate their application to matrices for which the original ACA fails.
description: © 2021 Jordon N. Blackburn
Stress Distribution in Two Intersecting Cylinders Under Pressure
Creators: name: Teig, Vernon Ellwood
Publisher: name: California Institute of Technology
Year: 1949
Subjects: Aeronautical engineering
Aeronautics

description: The experimental studies presented here were undertaken in an effort to determine the stress distribution in two circular cylinders intersecting at right angles and under internal pressure. The investigation was limited to tests of two specimens in the thick-walled cylinder range.

The experimental analysis led to the following conclusions:

1. The highest stress concentrations are located at an angle of about 14.5 degrees from the crotch centerline measured in the plane of the intersection.
2. The critical stress causing rupture is the tangential stress in the plane of the ellipse.
3. For the R/t ratios tested, the strength reduction as compared with a straight closed cylinder is approximately 50%.
4. It appears probable that bending effects for these thick-walled cylinders are of relatively minor importance.
Generalized (2+1) dimensional black hole by Noether symmetry
Creators: name: Darabi, F.
name: Atazadeh, K.
name: Rezaei-Aghdam, A.
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We use the Noether symmetry approach to find $f(R)$ theory of $(2+1)$ dimensional gravity and $(2+1)$ dimensional black hole solution consistent with this $f(R)$ gravity and the associated symmetry. We obtain $f({R})=D_1 R({n}/{n+1})({R}/{K})^{1/n}+D_2 R+D_3$, where the constant term $D_3$ plays no dynamical role. Then, we find general spherically symmetric solution for this $f(R)$ gravity which is potentially capable of being as a black hole. Moreover, in the special case $D_1=0, D_2={1}$, namely $f(R)=R+D_3$, we obtain a generalized BTZ black hole which, other than common conserved charges $m$ and $J$, contains a new conserved charge Q. It is shown that this conserved charge corresponds to the freedom in the choice of the constant term $D_3$ and represents symmetry of the action under the transformation $R \rightarrow R'=R+D_3$ along the killing vector $\partial_{R}$. The ordinary BTZ black hole is obtained as the special case where $D_3$ is {\it fixed} to be proportional to the infinitesimal cosmological constant and consequently the symmetry is broken via Q=0. We study the thermodynamics of the generalized BTZ black hole and show that its entropy can be described by the Cardy-Verlinde formula.
description: 13 pages, major revision, title change
The effect of Hydrogen atom on the Screw Dislocation Mobility in BCC Iron: A First-Principles Study
Creators: name: Itakura, M.
name: Kaburaki, H.
name: Yamaguchi, M.
name: Okita, T.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We investigate the effect of hydrogen on the mobility of a screw dislocation in body-centered cubic (bcc) iron using first-principles calculations, and show that an increase of screw dislocation velocity is expected for a limited temperature range. The interaction energy between a screw dislocation and hydrogen atoms is calculated for various hydrogen positions and dislocation configurations with careful estimations of the finite size effects, and the strongest binding energy of a hydrogen atom to the stable screw dislocation configuration is estimated to be $256\pm32$ meV. These results are incorporated into a line tension model of a curved dislocation line to elucidate the effect of hydrogen on the dislocation migration process. Both the softening and hardening effect of hydrogen, caused by the reduction of kink nucleation enthalpy and kink trapping, respectively, are evaluated. A clear transition between softening and hardening behavior at the lower critical temperature is predicted, which is in qualitative agreement with the experimental observation.
description: v2: minor revision, 16 pages, 15 figures; v3: to appear in Acta Materialia
One-point functions in finite volume/temperature: a case study
Creators: name: Szécsényi, I. M.
name: Takács, G.
name: Watts, G. M. T.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We consider finite volume (or equivalently, finite temperature) expectation values of local operators in integrable quantum field theories using a combination of numerical and analytical approaches. It is shown that the truncated conformal space approach, when supplemented with a recently proposed renormalization group, can be sufficiently extended to the low-energy regime that it can be matched with high precision by the low-temperature expansion proposed by Leclair and Mussardo. Besides verifying the consistency of the two descriptions, their combination leads to an evaluation of expectation values which is valid to a very high precision for all volume/temperature scales. As a side result of the investigation, we also discuss some unexpected singularities in the framework recently proposed by Pozsgay and Takács for the description of matrix elements of local operators in finite volume, and show that while some of these singularities are resolved by the inclusion of the class of exponential finite size corrections known as μ-terms, these latter corrections themselves lead to the appearance of new singularities. We point out that a fully consistent description of finite volume matrix elements is expected to be free of singularities, and therefore a more complete and systematic understanding of exponential finite size corrections is necessary.
description: v1: 29 pages, 10 eps figures. v2: 34 pages. A detailed comparison of the theoretically predicted and numerically computed cutoff dependence is added; notations explained in more details and some explanatory remarks are added; typos corrected
Why Comparable? A Multiverse Explanation of the Dark Matter-Baryon Coincidence
Creators: name: Bousso, Raphael
name: Hall, Lawrence
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The densities of dark and baryonic matter are comparable: ζ= ρ_D / ρ_B ~ O(1). This is surprising because they are controlled by different combinations of low-energy physics parameters. Here we consider the probability distribution over ζin the landscape. We argue that the Why Comparable problem can be solved without detailed anthropic assumptions, and independently of the nature of dark matter. Overproduction of dark matter suppresses the probability like 1/(1+ζ), if the causal patch is used to regulate infinities. This suppression can counteract a prior distribution favoring large ζ, selecting ζ~ O(1). This effect not only explains the Why Comparable coincidence but also renders otherwise implausible models of dark matter viable. For the special case of axion dark matter, Wilczek and independently Freivogel have already noted that a 1/(1+ζ) suppression prevents overproduction of a GUT-scale QCD axion. If the dark matter is the LSP, the effect can explain the moderate fine-tuning of the weak scale in simple supersymmetric models.
description: 20 pages JHEP format, 2 figures; v2: added references and a comment on multi-component dark matter; v3: final version for PRD, minor clarifications
Nucleon Structure using lattice QCD
Creators: name: Alexandrou, C.
name: Constantinou, M.
name: Drach, V.
name: Hatziyiannakou, K.
name: Jansen, K.
name: Kallidonis, C.
name: Koutsou, G.
name: Leontiou, T.
name: Vaquero, A.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: A review of recent nucleon structure calculations within lattice QCD is presented. The nucleon excited states, the axial charge, the isovector momentum fraction and helicity distribution are discussed, assessing the methods applied for their study, including approaches to evaluate the disconnected contributions. Results on the spin carried by the quarks in the nucleon are also presented.
description: Additional references included. Invited talk at the 3rd Workshop on the QCD Structure of the Nucleon (QCD-N'12), 22-26 October 2012, Bilbao, Spain. 8 pages & 14 figures
An investigation of the effect of the muzzle on the motion of the projectile in a recoilless gun
Creators: name: Woodward, Frank Arthur
Publisher: name: California Institute of Technology
Year: 1952
Subjects: Aeronautics

description: Expressions for the position and velocity of a projectile at any time in a recoilless gun are derived. The one dimensional wave equation is assumed to be valid in describing the motion of the gas. The muzzle velocity of the projectile is calculated, and compared with that obtained for the case in which no waves are reflected back from the muzzle. It is shown that the effect of the reflected waves is to increase the muzzle velocity. In the limiting case, when the ratio of the mass of gas initially in the barrel to the mass of the projectile is infinite, the theoretical muzzle velocity of the projectile is increased to twice the value that would be obtained if the effect of the reflected waves was neglected.
Strangeness and charmness content of nucleon from overlap fermions on 2+1-flavor domain-wall fermion configurations
Creators: name: Gong, M.
name: Alexandru, A.
name: Chen, Y.
name: Doi, T.
name: Dong, S. J.
name: Draper, T.
name: Freeman, W.
name: Glatzmaier, M.
name: Li, A.
name: Liu, K. F.
name: Liu, Z.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Lattice (hep-lat)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present a calculation of the strangeness and charmness contents and of the nucleon from dynamical lattice QCD with 2+1 flavors. The calculation is performed with overlap valence quarks on 2+1-flavor domain-wall fermion gauge configurations. The configurations are generated by the RBC collaboration on a 24^3*64 lattice with sea quark mass am_l=0.005, am_s=0.04, and inverse lattice spacing a^{-1}=1.73GeV. Both actions have chiral symmetry which is essential in avoiding contamination due to the operator mixing with other flavors. Nucleon propagator and the quark loops are both computed with stochastic grid sources, while low-mode substitution and low-mode averaging methods are used respectively which substantially improve the signal to noise ratio. We obtain the strangeness matrix element f_{T_{s}} = m_s / M_N = 0.0334(62), and the charmness content f_{T_{c}} = m_c / M_N = 0.094(31) which is resolved from zero by 3σprecision for the first time.
description: 34 pages, 18 figures; correct typos and minor updates; Figures updated, final version published in Phys. Rev. D 88, 014503 (2013)
Some considerations in the application of a gas turbine cycle to the manufacture of nitric oxide
Creators: name: MacLeod, Gordon John
Publisher: name: California Institute of Technology
Year: 1953
Subjects: Engineering and Applied Science

description: Certain problems associated with the application of a gas turbine cycle to the manufacture of nitric oxide are investigated. The feasibility of quenching the nitric oxide decomposition reaction with a De Laval nozzle is demonstrated. Thermochemical studies show that yields of nitric oxide approaching one percent are attainable in a gas turbine cycle. The severe turbine blade cooling problem can be surmounted with the use of either transpiration cooling or film cooling. Transpiration cooling with internal liquid vaporization is found to be the most promising method. The coolant requirements amount only to approximately one percent of the main stream mass flow per cooled-turbine-blade row. The effect of transpiration and film cooling upon cycle performance is negligible. Although all the problems associated with the application of a gas turbine cycle to the manufacture of nitric oxide appear to be surmountable, no attempt is, however, made in this study to ascertain the economical feasibility of the process. The answer to this question involves factors which are not purely technical and thus lies outside the scope of the thesis.
Granular Brownian motion with dry friction
Creators: name: Gnoli, A.
name: Puglisi, A.
name: Touchette, H.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The interplay between Coulomb friction and random excitations is studied experimentally by means of a rotating probe in contact with a stationary granular gas. The granular material is independently fluidized by a vertical shaker, acting as a 'heat bath' for the Brownian-like motion of the probe. Two ball bearings supporting the probe exert nonlinear Coulomb friction upon it. The experimental velocity distribution of the probe, autocorrelation function, and power spectra are compared with the predictions of a linear Boltzmann equation with friction, which is known to simplify in two opposite limits: at high collision frequency, it is mapped to a Fokker-Planck equation with nonlinear friction, whereas at low collision frequency, it is described by a sequence of independent random kicks followed by friction-induced relaxations. Comparison between theory and experiment in these two limits shows good agreement. Deviations are observed at very small velocities, where the real bearings are not well modeled by Coulomb friction.
description: 7 pages, 6 figures
Supersymmetric hybrid inflation with a light scalar
Creators: name: Orani, Stefano
name: Rajantie, Arttu
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Light scalar fields present during inflation can lead to interesting observable signatures, especially in models with non-equilibrium reheating dynamics. We study a supersymmetric hybrid inflation model with a third scalar whose lightness is protected by symmetry, using analytical and numerical techniques, and demonstrate that the amplitude, the spectral index and the non-Gaussianity parameter fNL of the primordial curvature perturbation are within the Planck observational bounds for suitable parameter values.
description: 8 pages, 7 figures, v2: updated to journal version
Half - Quantum Vortices
Creators: name: Mineev, V. P.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Unlike to superfluid $^4$He the superfluid $^3$He-A support the existence of vortices with half quantum of circulation as well as single quantum vortices. The singular single quanta vortices as well as nonsingular vortices with 2 quanta of circulation have been revealed in rotating $^3$He-A. However, the half quantum vortices in open geometry always possess an extra energy due to spin-orbit coupling leading to formation of domain wall at distances larger than dipole length $\sim 10^{-3}cm$ from the vortex axis. Fortunately the same magnetic dipole-dipole interaction does not prevent the existence of half-quantum vortices in the polar phase of superfluid $^3$He recently discovered in peculiar porous media "nematically ordered" aerogel. Here we discuss this exotic possibility. The discoveries of half-quantum vortices in triplet pairing superconductor Sr$_2$RuO$_4$ as well in the exciton-polariton condensates are the other parts of the story about half-quantum vortices also described in the paper.
description: 6 pages, no figures
title: УСТОЙЧИВОСТЬ ПОЧВ К РАЗРУШЕНИЮ ВЕТРОМ  В АГРОЛЕСОЛАНДШАФТАХ НА ФОНЕ  СИСТЕМЫ ЗЕМЛЕДЕЛИЯ NO-TILL
title: RESISTANCE OF SOILS TO DESTRUCTION BY WIND IN AGROFOREST  LANDSCAPES AGAINST THE BACKGROUND OF THE NO-TILL FARMING SYSTEM
Creators: name: Волошенкова, Т.В.
Publisher: name: ФГБНУ "Северо-Кавказский федеральный научный аграрный центр"
Year: 2019

description: В сети лесных полос степной зоны Нижнего Поволжья изучена сезонная дина-мика структуры верхнего (0-5 см) слоя почвы на фоне системы земледелия No-till. Установлено, что открытая поверхность южных карбонатных черноземов дефляционно опасна в любое время года. Выявлены два пика распыления – ранней весной и перед уборкой зерновых культур. В первый период содержание частиц диаметром менее 1 мм составило 33-47%, во второй – 60-61%. Полезащитные лесные полосы снижали распыление почвы в зоне до 10-15 высот насаждений (Н) почти в 2 раза. Южные кар-бонатные черноземы генетически предрасположены к выдуванию, поэтому их необхо-димо защитить экраном из растительных остатков. Система земледелия No-till имеет преимущество, так как позволяет всю стерню оставить на поверхности поля, особенно при уборке методом очеса растений. При этом остается около 4 т/га растительных остатков озимой пшеницы. К весне ее количество сокращается в 2 раза, а после посева яровых культур остается всего около 25% от первоначального количества. Поэтому си-стема No-till будет наиболее эффективна в комплексе с полезащитными лесными поло-сами.
description: In the network of the forest shelterbelts in the steppe zone of the Lower Volga region, the seasonal dynamics of the structure in the upper (0-5 cm) soil layer was studied against the background of the No-till farming system. It has been established that the open surface of the southern carbonate chernozems is deflationary threat at any time of the year. Two peaks of dispersion were revealed: in the early spring and before harvesting of grain crops. In the first period, the content of particles with a diameter of less than 1 mm was 33-47%, in the second it was 60-61%. The field-protecting forest belts reduced the soil dispersion in the zone to 10-15 plantation heights (H)  almost 2 times. Southern carbonate chernozems are genetically pre-disposed to blowing, so they need to be protected by a screen from plant debris.  The No-till farming system has the advantage of allowing the entire stubble to be left on the surface of the field, especially when harvesting by plant combing. At the same time, about 4 tons/hectare of winter wheat stubble remains. By spring, its number is reduced by 2 times, and after the sowing spring crops only about 25% of the initial amount remains. Therefore, the No-till sys-tem will be most effective in combination with field-protecting forest shelterbelts.
Effective Corporate Governance Practices and Sustainable Performance in the Nigerian Banking Industry
Creators: name: Nagbiku, Moses
Publisher: name: Leeds Beckett University
Year: 2022
Subjects: Uncategorized

description: This study investigates the relationship between effective corporate governance practices and sustainable performance in the Nigerian banking industry. This investigation covers a period of five years, from 2008 to 2012. The strategic question that this research sets out to investigate is: “how do effective corporate governance practices impact on sustainable performance in the Nigerian banking industry?” This research is motivated by the desire to better understand the operationalisation of corporate governance principles/policies and the triple-bottom-line concept of sustainable performance in the Nigerian banking industry. The research philosophy is subjectivism with regard to ontology and the epistemology is interpretivism. Coming from the perspective of social constructionism, due consideration is given to social actors that are involved to establish reality. The research methodology is qualitative, the research design is comparative - studying six Nigerian banks, data sampling technique is purposive, and the data analysis is thematic. The research findings reveal that effective corporate governance practices will invariably impact on sustainable performance in the Nigerian banking industry, if the banks are committed to sustainable banking practices. This investigation will be of benefit to operators and practitioners who will better appreciate the importance of the operationalisation of corporate governance principles/polices and its integration with sustainability. The result of such integration is the triple-bottom-line effects of sustainable performance namely, economic, environmental and social. In conclusion, this study will encourage the banking industry to embrace sustainable banking practices with the aforementioned and attendant benefits of sustainable performance, for the Nigerian economy. Key words: effective corporate governance practices, corporate performance, banking industry, sustainability/sustainable performance, effectiveness, efficiency and efficacy.
Taking the Bull by the Horns: Representing Gender through Animals in Franco's Spain
Creators: name: Lopez-Rodriguez, Irene
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2021
Subjects: Gender
Animals
Symbols
Franco
Dictatorship
Discourse
Counter-discourse
VOX
Politics
Culture

description: This dissertation analyzes the (de)construction of gender and nation through animal symbols in Franco’s Spain. The project explores, first, a web of miscellaneous discourses articulated around the official bestiary rhetoric that serve in the composition of uniform gender models tailor-made for the virile totalitarian state. The selection of texts presented is eclectic, both in its nature and form. It encompasses a wide repertoire of multi-media discourses (i.e., scientific, religious, legal, educational, political, commercial, humorous and popular) presented visually (movies, posters, comics, cartoons, flags, advertisements, logotypes), aurally (songs, harangues, sermons, speeches, radio programs) and in the written form (literary excerpts, newspapers, magazines, medical and religious treatises, conduct manuals, epistles), and whose aim is, ultimately, to illustrate the dissemination and scope of zoomorphic images in the representation of nation and gender during the Francoist dictatorship. Apart from providing a panoramic view of the gendered fauna, these historical documents will also serve as the unifying thread to unravel the complexities of several censored artistic productions that cunningly resort to the prevailing bestial iconography to attack the androcentric state. By focusing on the animalized portrayals of the female characters of la Gata [the She-Cat] in Margarita Alexandre and Rafael María Torrecilla’s movie La gata (1956), la Loba [the She-wolf] in Rafael de León, Andrés Moles and Manuel López Quiroga’s copla “La Loba” (1960), and the surrealistic centaur woman Albina in Ana María Moix’s novel Walter, ¿por qué te fuiste? (1973), this work attempts to illustrate the co-existence of a counter discourse able to re-define the monolithic pillars of gender and nation upon which the Francoist regime was constructed. Finally, to highlight the relevance of animal symbolism in the formation of concepts of gender and nation, this dissertation notes a similar deployment of the Francoist bestiary rhetoric in the nationalist discourse of the far-right Spanish political party VOX (2013-present).
title: SOUTHERN PINE BEETLE-SPECIFIC RNA INTERFERENCE DEMONSTRATES NO EFFECTS ON NONTARGET INSECTS
Creators: name: Hollowell, Hannah Marie
Publisher: name: University of Kentucky Libraries
Year: 2021
Subjects: subject: FOS: Other agricultural sciences
valueUri: http://www.oecd.org/science/inno/38235147.pdf

description: The endemic southern pine beetle (SPB), Dendroctonus frontalis Zimmermann, is a highly destructive bark beetle that has devastated coniferous forests of the southern United States for decades. Traditional management strategies have been unable to respond effectively to largescale SPB outbreaks, prompting exploration of novel techniques including RNA interference (RNAi). Double-stranded RNAs (dsRNAs) are effective at triggering gene silencing and inducing mortality in SPB, but determining delivery methods and demonstrating specificity of the treatments is necessary before this technology may progress to deployment.

I evaluated three SPB-specific dsRNAs on model nontarget insects to assess potential lethal effects, sublethal effects such as larval weight gain, adult emergence or fecundity, and gene silencing. The model insects, a predator, herbivore, and pollinator, were evaluated in laboratory bioassays following dsRNA exposure and results from these studies demonstrate no nontarget effects on representative model insects.

Additionally, I evaluated these three SPB-specific dsRNAs on pine-associated insects that co-occur with SPB, including a pine engraver, pine defoliator, and decomposer. Lethal effects, sublethal effects such as larval weight gain or food consumption, and relative gene expression were analyzed for these insects, and results show no nontarget effects on these insects that could encounter the treatments were they to be deployed in a pine ecosystem.
description: © 2021 Hannah Marie Hollowell
Cooperative Synchronization in Wireless Networks
Creators: name: Etzlinger, Bernhard
name: Wymeersch, Henk
name: Springer, Andreas
Publisher: name: arXiv
Year: 2013
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences
subject: C.2.1
subject: 68W15

description: Synchronization is a key functionality in wireless network, enabling a wide variety of services. We consider a Bayesian inference framework whereby network nodes can achieve phase and skew synchronization in a fully distributed way. In particular, under the assumption of Gaussian measurement noise, we derive two message passing methods (belief propagation and mean field), analyze their convergence behavior, and perform a qualitative and quantitative comparison with a number of competing algorithms. We also show that both methods can be applied in networks with and without master nodes. Our performance results are complemented by, and compared with, the relevant Bayesian Cramér-Rao bounds.
Electron tunneling through graphene-based double barriers driven by a periodic potential
Creators: name: Ojeda-Collado, H. P.
name: Rodríguez-Castellanos, C.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Photon-assisted charge transport through a double barrier structure under a time periodic field in graphene is studied. Within the framework of the Floquet formalism and using the transfer matrix method, the transmission probabilities for the central band and sidebands are calculated. A critical phase difference between the harmonic potentials at the barriers, which cancels transmission through the inelastic sidebands due to quantum interference is found. This phenomenon could be of help to design graphene based filters and high-frequency radiation detectors. Quenching of resonant tunneling by the harmonic field applied to the barriers or the well is also discussed.
description: 5 pages, 8 figures
A single-spin precessing gravitational wave in closed form
Creators: name: Lundgren, A.
name: O'Shaughnessy, R.
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: In coming years, gravitational wave detectors should find black hole-neutron star binaries, potentially coincident with astronomical phenomena like short GRBs. These binaries are expected to precess. Gravitational wave science requires a tractable model for precessing binaries, to disentangle precession physics from other phenomena like modified strong field gravity, tidal deformability, or Hubble flow; and to measure compact object masses, spins, and alignments. Moreover, current searches for gravitational waves from compact binaries use templates where the binary does not precess and are ill-suited for detection of generic precessing sources. In this paper we provide a closed-form representation of the single-spin precessing waveform in the frequency domain by reorganizing the signal as a sum over harmonics, each of which resembles a nonprecessing waveform. This form enables simple analytic calculations (e.g., a Fisher matrix) with easily-interpreted results. We have verified that for generic BH-NS binaries, our model agress with the time-domain waveform to 2\%. Straightforward extensions of the derivations outlined here [and provided in full online] allow higher accuracy and error estimates.
description: v2: test script and supplementary derivation details provided
Decoy-state quantum key distribution with biased basis choice
Creators: name: Wei, Zhengchao
name: Wang, Weilong
name: Zhang, Zhen
name: Gao, Ming
name: Ma, Zhi
name: Ma, Xiongfeng
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We propose a quantum key distribution scheme that combines a biased basis choice with the decoy-state method. In this scheme, Alice sends all signal states in the $Z$ basis and decoy states in the $X$ and $Z$ basis with certain probabilities, and Bob measures received pulses with optimal basis choice. This scheme simplifies the system and reduces the random number consumption. From the simulation result taking into account of statistical fluctuations, we find that in a typical experimental setup, the proposed scheme can increase the key rate by at least 45% comparing to the standard decoy-state scheme. In the postprocessing, we also apply a rigorous method to upper bound the phase error rate of the single-photon components of signal states.
description: 17 pages, 2 figures
An investigation of flow separation in an overexpanded supersonic nozzle
Creators: name: McKenney, John Dill
Publisher: name: California Institute of Technology
Year: 1949
Subjects: propeller
tip vortices
Aeronautics
cavitation

description: An apparatus for the investigation of flow separation in a supersonic nozzle has been designed and constructed. Nozzle wall pressure distributions and shadowgraphs showing the associated shock wave configuration have been obtained for a range of different stagnation pressures and constant exit pressure.

The pressure ratios were such that the theoretical nozzle exit pressure, without separation, was always less than atmospheric pressure. With the nozzle contour and pressure ratios investigated it is found that separation of flow from the nozzle walls always occurs. The separation is accompanied by a weak oblique shock wave of such strength that the flow deflection through it is approximately constant, independent of the location of the point of separation within the nozzle. The pressure adjustment from nozzle to exit does not occur through a normal shock wave.

At pressure ratios below a certain value a definite asymmetry of flow appears in which the detached jet deflects away from the nozzle symmetry axis. At higher pressure ratios, the flow becomes stable with separation occurring at the same distance from the nozzle throat on both upper and lower walls.
Photometric Redshifts and Systematic Variations in the SEDs of Luminous Red Galaxies from the SDSS DR7
Creators: name: Greisel, Natascha
name: Seitz, Stella
name: Drory, Niv
name: Bender, Ralf
name: Saglia, Roberto
name: Snigula, Jan
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We describe the construction of a template set of spectral energy distributions (SEDs) for the estimation of photometric redshifts of luminous red galaxies (LRGs) with a Bayesian template fitting method. By examining the color properties of several publicly available SED sets within a redshift range of 00.15) of 0.12%. We show that templates that optimally describe the brightest galaxies (-24.5
description: 21 pages, 25 figures, accepted for publication in the Astrophysical Journal (ApJ)
Shape and symmetry of a fluid-supported elastic sheet
Creators: name: Diamant, Haim
name: Witten, Thomas A.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Pattern Formation and Solitons (nlin.PS)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences

description: A connection between the dynamics of a sine-Gordon chain and a certain static membrane folding problem was recently found. The one-dimensional membrane profile is a cross-section of the position-time sine-Gordon amplitude profile. Here we show that when one system is embedded in a higher-dimensional system in this way, obvious symmetries in the larger system can lead to nontrivial symmetries in the embedded system. In particular, a thin buckled membrane on a fluid substrate has a continuous degeneracy that interpolates between a symmetric and an antisymmetric fold. We find the Hamiltonian generator of this symmetry and the corresponding conserved momentum by interpreting the simple translational symmetries of the sine-Gordon chain in terms of the embedded coordinates. We discuss possible extensions to other embedded dynamical systems.
description: 8 pages
Initial motion of a rocket moving on a stretched cable
Creators: name: Weinberg, Warren E.
Publisher: name: California Institute of Technology
Year: 1952
Subjects: Aeronautics

description: The practicability of using a stretched cable for a rocket launching device is dependent primarily upon the transverse movement of the rocket and the stresses involved in the system. This requires analysis of the effects of the moving rocket mass on the cable from the instant of contact, and the problem reduces to one of wave propagation.

The analysis here is restricted essentially to developing a procedure by which the initial motion of the mass can be calculated, and an expression is obtained which permits determination of the deflections. The problem is approached by first assuming that the mass exerts a constant transverse force on the cable. Admittedly, this is a simplifying assumption, and the result is not valid for the instant the mass hits the cable or for a short time thereafter because the inertia of the mass is not considered.

Next, the problem is solved by taking into account the dynamics of the mass, and the solution reveals that the path of the actual mass deviates from the force path by as much as twenty percent during the initial motion but soon returns to the force path. The mass does not exert its full force on the cable at the instant of contact, but comes down on the cable with full force a short time later. Since maximum stresses on the system occur at this time, this factor is an important result of the analysis. Further, it is shown that increased velocity of the mass increases the deviation from the force path, and increased mass lengthens the time of return to the force path.
Density of range capturing hypergraphs
Creators: name: Axenovich, Maria
name: Ueckerdt, Torsten
Publisher: name: Journal of Computational Geometry
Year: 2016

description: $\newcommand{\cH}{\mathcal{H}}$For a finite set $X$ of points in the plane, a set $S$ in the plane, and a positive integer $k$, we say that a $k$-element subset $Y$ of $X$ is captured by $S$ if there is a homothetic copy $S'$ of $S$ such that $X\cap S' = Y$, i.e., $S'$ contains exactly $k$ elements from $X$. A $k$-uniform $S$-capturing hypergraph $\cH = \cH(X,S,k)$ has a vertex set $X$ and a hyperedge set consisting of all $k$-element subsets of $X$ captured by $S$. In case when $k=2$ and $S$ is convex these graphs are planar graphs, known as \emph{convex distance function Delaunay graphs}. In this paper we prove that for any $k\geq 2$, any $X$, and any convex compact set $S$, the number of hyperedges in $\cH(X,S,k)$ is at most $(2k-1)|X| - k^2 + 1 - \sum_{i=1}^{k-1}a_i$, where $a_i$ is the number of $i$-element subsets of $X$ that can be separated from the rest of $X$ with a straight line. In particular, this bound is independent of $S$ and indeed the bound is tight for all ``round'' sets $S$ and point sets $X$ in general position with respect to $S$. This refines a general result of Buzaglo, Pinchasi and Rote (2013) stating that every pseudodisc topological hypergraph with vertex set $X$ has $O(k^2|X|)$ hyperedges of size $k$ or less.
description: Journal of Computational Geometry, Vol. 7 No. 1 (2016)
Incidences with $k$-non-degenerate sets and their applications
Creators: name: Basit, Abdul
name: Sheffer, Adam
Publisher: name: Journal of Computational Geometry
Year: 2014

description: We study point-sphere and point-plane incidences in the three-dimensional space. In particular, for $1 < k < n$, we say that a set of spheres (resp., of planes) is $k$-non-degenerate if no circle is contained in $k$ spheres of the set (resp., if no line is contained in $k$ planes of the set). We prove that, for every $\varepsilon>0$, the number of incidences between a set of $m$ points and a $k$-non-degenerate set of $n$ spheres is \[ O(m^{3/4+\varepsilon}n^{3/4}k^{1/4}+n+mk).\] Similarly, we prove that, for every $\varepsilon>0$, the number of incidences between a set of $m$ points and a $k$-non-degenerate set of $n$ planes is \[ O(m^{4/5+\varepsilon}n^{3/5}k^{2/5} + n + mk). \] These bounds are obtained by using the polynomial partitioning technique, recently introduced by Guth and Katz. More specifically, in our proofs we use a pair of constant-degree partitioning polynomials. We also present a couple of applications of $k$-non-degenerate sets: (i) We consider an extension of the three-dimensional unit distances problem, in which we are given a set $D$ of $k$ distinct distances and ask for a three-dimensional set of $m$ points that maximizes the number of pairs of points that span a distance from $D$. By relying on $k$-non-degenerate sets of spheres, we prove an upper bound of $O(m^{236/149+\varepsilon}k^{125/149})$ for the problem (which improves the trivial bound for large values of $k$). Â Â Â (ii) We consider the maximum number of incidences between a three-dimensional set of $n$ planes (without any restrictions) and a set of $m$ points, such that no $k$ points are collinear. Our bound for $k$-non-degenerate planes immediately implies a bound of $O(n^{4/5+\varepsilon}m^{3/5}k^{2/5} + m + nk)$ for this problem, generalizing the previous bound $O(n^{4/5}m^{3/5} + n\log m)$ for the specific case where no three points are collinear (up to the $\varepsilon$ in the exponent).
description: Journal of Computational Geometry, Vol. 5 No. 1 (2014)
Kinetic and spectral resolution of two components of delayed emission from Chlorella pyrenoidosa
Creators: name: Kindergan, Michael
Publisher: name: California Institute of Technology
Year: 1972
Subjects: Chemistry

description: 1. Decay kinetics of delayed emission from Chlorella pyrenoidosa have been determined with a higher degree of precision than has previously been possible. The decay in the msec-to-sec interval after excitation can be represented accurately by the sum of two exponential decays--a "fast component" whose intensity- dependent lifetime ranges between 3 msec and 10 msec and a "slow component" whose lifetime ranges between 170 msec and 215 msec.

2. The slow component can be isolated by monitoring the emission at 685 nm for long times (> 30 msec) after high or low intensity excitation, or at any time in the msec to sec interval following low intensity (< 0.9 mW/cm^2) excitation. Saturation of the slow component occurs in the low intensity region where oxygen evolution is linear with light intensity. The temperature sensitivity of the slow component indicates involvement of an enzymatic and/or diffusion-limited process.

3. The emission spectrum of the fast component is identical to the fluorescence emission spectrum of the cells, with a peak at 685 nm and a shoulder between 710 and 730 nm. The intensity of the fast component parallels the reduction of System 2 electron acceptors and reaches a maximum level when photochemistry is light saturated. This fact was established by simultaneous measurements of oxygen evolution and delayed emission.

4. The fast component can be selectively inhibited by 3(3, 4-dichlorophenyl)-1, 1-dimethylurea, heat or ultraviolet irradiation. The slow component can be selectively inhibited by hydroxylamine or low temperatures.

5. Possible mechanisms resulting in fast and slow component delayed emission are discussed in view of the experimental results.
On projections of metric spaces
Creators: name: Kozdoba, Mark
Publisher: name: Journal of Computational Geometry
Year: 2014

description: Let $X$ be a metric space and let $\mu$ be a probability measure on it. Consider a Lipschitz map $T: X \rightarrow \mathbb{R}^n$, with Lipschitz constant $\leq 1$. Then one can ask whether the image $TX$ can have large projections on many directions. For a large class of spaces $X$, we show that there are directions $\phi \in \mathbb S^{n-1}$ on which the projection of the image $TX$ is small on the average, with bounds depending on the dimension $n$ and the eigenvalues of the Laplacian on $X$.
description: Journal of Computational Geometry, Vol. 5 No. 1 (2014)
Computational aspects of the Hausdorff distance in unbounded dimension
Creators: name: König, Stefan
Publisher: name: Journal of Computational Geometry
Year: 2014

description: We study the computational complexity of determining the Hausdorff distance oftwo polytopes given in halfspace- or vertex-presentation in arbitrary dimension. Sub-sequently, a matching problem is investigated where a convex body is allowed to behomothetically transformed in order to minimize its Hausdorff distance to another one. For this problem, we characterize optimal solutions, deduce a Helly-type theorem and give polynomial time (approximation) algorithms for polytopes.
description: Journal of Computational Geometry, Vol. 5 No. 1 (2014)
Adiabatic and Isocurvature Perturbation Projections in Multi-Field Inflation
Creators: name: Gordon, Chris
name: Saffin, Paul M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Current data are in good agreement with the predictions of single field inflation. However, the hemispherical asymmetry seen in the cosmic microwave background data, may hint at a potential problem. Generalizing to multi-field models may provide one possible explanation. A useful way of modeling perturbations in multi-field inflation is to investigate the projection of the perturbation along and perpendicular to the background fields' trajectory. These correspond to the adiabatic and isocurvature perturbations. However, it is important to note that in general there are no corresponding adiabatic and isocurvature fields. The purpose of this article is to highlight the distinction between a field redefinition and a perturbation projection. We provide a detailed derivation of the evolution of the isocurvature perturbation to show that no assumption of an adiabatic or isocurvature field is needed. We also show how this evolution equation is consistent with the field covariant evolution equations for the isocurvature perturbation in the flat field space limit.
description: 11 pages, 1 figure; v2: Minor typos corrected, reflects published version
Unidentified
Creators: name: (:Unav)
Publisher: name: Columbia University
Year: 2019
Subjects: Magnetic recorders and recording

description: "I'm Shy, Mary Ellen, I'm Shy" by Stanley Holloway plays. Kenneth Miller goes to an antique show and listens to music boxes. Unknown live performers sing Sammy Davis Jr.'s "Please Don't Talk About Me When I'm Gone," Al Jolson's "You Made Me Love You," and another unknown song.
Die Autor*innen dieses Bandes
Creators: name: Heimbach-Steins, Marianne
Publisher: name: Jahrbuch für Christliche Sozialwissenschaften
Year: 2022

description: Jahrbuch für Christliche Sozialwissenschaften, Bd. 63 (2022): Christliche Sozialethik – eine sozialwissenschaftliche und theologische Disziplin