cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Periodic and Chaotic Traveling Wave Patterns in Reaction-Diffusion/ Predator-Prey Models with General Nonlinearities
Creators: name: Mancas, Stefan C.
name: Choudhury, Roy S.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Dynamical Systems (math.DS)
subject: Chaotic Dynamics (nlin.CD)
subject: Populations and Evolution (q-bio.PE)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: Traveling wavetrains in generalized two-species predator-prey models and two-component reaction-diffusion equations are considered. The stability of the fixed points of the traveling wave ODEs (in the usual "spatial" variable) is considered. For general functional forms of the nonlinear prey birthrate/prey deathrate or reaction terms, a Hopf bifurcation is shown to occur at two different critical values of the traveling wave speed. The post-bifurcation dynamics is investigated for five different functional forms of the nonlinearities. In cases where the bifurcation is supercritical, the post-bifurcation behaviour yields stable periodic orbits of the traveling-wave ODEs in the spatial variable. These correspond to stable periodic wavetrains of the full PDEs. Subcritical Hopf bifurcations yield more complex post-bifurcation dynamics in the PDE wavetrains. In special cases where the subcritical bifurcation marks the end of the regime of stability, the post-bifurcation behavior in the spatial ODEs is chaotic, corresponding to wavetrains of the original PDEs which are spatially coherent, but have chaotic temporal dynamics. All the models are integrated numerically to investigate the post-bifurcation dynamics and chaotic regimes are characterized by computing power spectra, autocorrelation functions, and fractal dimensions.
description: 19 pages, 9 figures
Independent Component Analysis for Filtering Airwaves in Seabed Logging Application
Creators: name: Ansari, Adeel
name: Shafie, Afza Bt
name: Said, Abas B Md
name: Ansari, Seema
Publisher: name: arXiv
Year: 2013
Subjects: subject: Other Computer Science (cs.OH)
subject: Geophysics (physics.geo-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Marine controlled source electromagnetic (CSEM) sensing method used for the detection of hydrocarbons based reservoirs in seabed logging application does not perform well due to the presence of the airwaves (or sea-surface). These airwaves interfere with the signal that comes from the subsurface seafloor and also tend to dominate in the receiver response at larger offsets. The task is to identify these air waves and the way they interact, and to filter them out. In this paper, a popular method for counteracting with the above stated problem scenario is Independent Component Analysis (ICA). Independent component analysis (ICA) is a statistical method for transforming an observed multidimensional or multivariate dataset into its constituent components (sources) that are statistically as independent from each other as possible. ICA-type de-convolution algorithm that is FASTICA is considered for mixed signals de-convolution and considered convenient depending upon the nature of the source and noise model. The results from the FASTICA algorithm are shown and evaluated. In this paper, we present the FASTICA algorithm for the seabed logging application.
description: 7 pages, 13 figures
Essays on the development of a theory of strategy formation in hospitals
Creators: name: Schrader, Jan Simon
Publisher: name: Hannover : Institutionelles Repositorium der Leibniz Universität Hannover
Year: 2019
Subjects: subject: Strategy Formation
subject: Strategic Issues
subject: Strategic Agenda
subject: Case Study
subject: Qualitative Research
subject: Theory Development
subject: Strategiebildung
subject: Strategische Themen
subject: Strategische Agenda
subject: Fallstudie
subject: Qualitative Forschung
subject: Theorieentwicklung
subject: Dewey Decimal Classification::300 | Sozialwissenschaften, Soziologie, Anthropologie::330 | Wirtschaft

description: Hospitals experienced far-reaching changes over the past decades. A new market-driven economic environment leads to an intensified competition on the hospital market and challenges the traditional understanding of the strategy formation process. Given that strategic decisions must meet economic and medical demands, strategic issues cannot longer be solely developed and processed by management professionals. Instead, successful strategy formation also depends on the development and processing of unintended strategic issues generated through the expertise of medical professionals. Consequently, manager’s competence and medical expertise have to be connected to capitalize on their mutually exclusive knowledge. In sum, the literature is unambiguous in that hospitals represent complex organizations in which the simultaneous processing of intended strategic issues from the board of executives and unintended strategic issues from medical professionals is of utmost importance. However, empirical evidence on strategy formation as a collaboration between management and medical professionals is scarce and theory of strategy formation in hospitals is poor. The aim of this doctoral thesis is to address these research gaps by developing a theory of strategy formation in hospitals, thereby understanding how and why strategic issues are processed and integrated into the strategic agenda.
Statue of Mahatma Gandhi in courtyard, Kalimpong, India, with Herbert Fader
Creators: name: (:Unav)
Publisher: name: Columbia University
Year: 2020
Subjects: Statues
Abandoned buildings
Courtyards

description: Statue of Mahatma Gandhi in courtyard of Gauripur House (a.k.a. Gouripur) of Rabindranath Tagore, Kalimpong, India, with Herbert Fader
GRB 090510: a disguised short GRB with the highest Lorentz factor and circumburst medium
Creators: name: Muccino, M.
name: Ruffini, R.
name: Bianco, C. L.
name: Izzo, L.
name: Penacchioni, A. V.
name: Pisani, G. B.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: GRB 090510, observed both by Fermi and AGILE satellites, is the first bright short-hard Gamma-Ray Burst (GRB) with an emission from the keV up to the GeV energy range. Within the Fireshell model, we interpret the faint precursor in the light curve as the emission at the transparency of the expanding e+e- plasma: the Proper-GRB (P-GRB). From the observed isotropic energy we assume a total energy Ee+e-=(1.10+-0.06)*10^53 erg and derive a Baryon load B=(1.45+-0.28)*10^(-3) and a Lorentz factor at transparency Gamma=(6.7+-1.6)*10^2. The main emission 0.4 s after the initial spike is interpreted as the extended afterglow, due to the interaction of the ultrarelativistic baryons with the CircumBurst Medium (CBM). Using the condition of fully radiative regime, we infer a CBM average spherically symmetric density of nCBM=(1.85+-0.14)10^3 cm^(-3), one of the highest found in the Fireshell model. The value of the filling factor, 1.5*10^(-10)
description: 5 pages, 3 figures, ApJ in press
Thematic tactile maps for accessible flood mitigation planning: design and evaluation
Creators: name: Cole, Harrison
name: Robinson, Anthony
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Medicine
subject: Genetics
subject: FOS: Biological sciences
subject: Neuroscience
subject: Ecology
subject: Biological Sciences not elsewhere classified
subject: Mental Health

description: Maps are frequently employed in the natural hazard mitigation planning (NHMP) process for analyze a community’s vulnerability to hazards and illustrating the character of potential hazards. But because the encoded information of these maps relies on visual access, blind or low-vision (B/LV) people who want to contribute to their community’s NHMP efforts are therefore effectively excluded from any stage of the process involving maps. In response, we investigate tactile flood maps as an accessible tool for NHMP. Our study proposes a workflow for creating thematic tactile flood maps using existing resources, methods, and design conventions, and then evaluates those thematic tactile maps to understand user confidence amongst B/LV users. This work contributes a proposed configuration of tactile mapping resources to be used for NHMP and evaluates user confidence while using those resources. Results suggest that B/LV users respond positively to using tactile maps in a high-stakes context such as NHMP, and that tactile maps can expand the number and diversity of people who are able to contribute to NHMP. To maximize contributions, we recommend that future tactile map research invest a greater amount of attention to developing resources for B/LV people to create, edit, and distribute maps themselves.
Development of a comprehensive database of scattering environment conditions and simulation constraints for offshore wind turbines
Creators: name: Huebler, Clemens
name: Gebhardt, Cristian Guillermo
name: Rolfes, Raimund
Publisher: name: Göttingen : Copernicus
Year: 2017
Subjects: subject: wind turbines
subject: real high-quality data
subject: offshore wind turbines
subject: probabilistic design approaches
subject: Dewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und Maschinenbau
subject: Dewey Decimal Classification::600 | Technik

description: For the design and optimisation of offshore wind turbines, the knowledge of realistic environmental conditions and utilisation of well-founded simulation constraints is very important, as both influence the structural behaviour and power output in numerical simulations. However, real high-quality data, especially for research purposes, are scarcely available. This is why, in this work, a comprehensive database of 13 environmental conditions at wind turbine locations in the North and Baltic Sea is derived using data of the FINO research platforms. For simulation constraints, like the simulation length and the time of initial simulation transients, well-founded recommendations in the literature are also rare. Nevertheless, it is known that the choice of simulation lengths and times of initial transients fundamentally affects the quality and computing time of simulations. For this reason, studies of convergence for both parameters are conducted to determine adequate values depending on the type of substructure, the wind speed, and the considered loading (fatigue or ultimate). As the main purpose of both the database and the simulation constraints is to compromise realistic data for probabilistic design approaches and to serve as a guidance for further studies in order to enable more realistic and accurate simulations, all results are freely available and easy to apply.
Marco Pallis with Richard Nicholson(?) at Tibet Mirror Press office (Mackenzie Cottage). Jigme Taring and W.D. (Wangchuk Deden) Shakabpa, finance minister of Tibet, at Tibet Mirror Press office.
Creators: name: (:Unav)
Publisher: name: Columbia University
Year: 2020
Subjects: Tibetologists

description: Adjacent photos from a contact sheet, featuring on the left: Marco Pallis with climbing partner, Richard Nicholson(?), at the Tibet Mirror Press office (Makcenzie Cottage)-- on the right: Jigme Taring and W.D. (Wangchuk Deden) Shakabpa, finance minister of Tibet.
Gangs can mgon po Bstan 'dzin ryga mtsho'I rje, Kun zigs pan chen chos kyi rgyal mtshan mchog = Yi dai zong shi
Creators: name: (:Unav)
Publisher: name: Columbia University
Year: 2020
Subjects: Dalai lamas
Panchen lamas

description: Poster featuring thangka-style painting of the Dalai Lama and the Panchen Lama (possibly painted by Amdo Jampa?)
An identification procedure of multi-input Wiener models for the distortion analysis of nonlinear circuits
Creators: name: Weng, T.
name: Stegemann, S.
name: John, Werner
name: Mathis, Wolfgang
Publisher: name: Göttingen : Copernicus GmbH
Year: 2013
Subjects: subject: Black box approach
subject: Correlation analysis
subject: Distortion analysis
subject: Distortion behaviors
subject: Identification procedure
subject: Interfering signals
subject: Nonlinear circuit
subject: System identification procedure
subject: Electromagnetic pulse
subject: White noise
subject: Nonlinear equations
subject: Dewey Decimal Classification::600 | Technik

description: In this contribution, a system identification procedure of a two-input Wiener model suitable for the analysis of the disturbance behavior of integrated nonlinear circuits is presented. The identified block model is comprised of two linear dynamic and one static nonlinear block, which are determined using an parameterized approach. In order to characterize the linear blocks, an correlation analysis using a white noise input in combination with a model reduction scheme is adopted. After having characterized the linear blocks, from the output spectrum under single tone excitation at each input a linear set of equations will be set up, whose solution gives the coefficients of the nonlinear block. By this data based black box approach, the distortion behavior of a nonlinear circuit under the influence of an interfering signal at an arbitrary input port can be determined. Such an interfering signal can be, for example, an electromagnetic interference signal which conductively couples into the port of consideration.
Natural language processing meets spatial time series analysis and geovisualization: identifying and visualizing spatio-topical sentiment trends on Twitter
Creators: name: Kwon, Hoeyun
name: Koylu, Caglar
name: Dietrich, Bryce J.
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Medicine
subject: Evolutionary Biology
subject: FOS: Biological sciences
subject: Environmental Sciences not elsewhere classified
subject: Ecology
subject: Sociology
subject: FOS: Sociology

description: Previous studies have introduced various approaches for visualizing the spatial and temporal distributions of sentiments expressed on social media. However, many existing methods either overlook the evolving nature of sentiments or fail to account for the spatial distribution of sentiment trends related to specific topics. To gain a comprehensive understanding of how sentiments evolve in relation to topics and geographies, it is essential to capture the dynamic nature of sentiment through time series analysis and geovisualization. This article introduces a workflow that combines natural language processing, spatial time series analysis, and geovisualization techniques to identify and visualize the variations in sentiment trends on Twitter across different geographic regions and topics. By examining the 2016 presidential debates as a case study, we uncover distinct temporal patterns in sentiment distributions across various topics and states. Our findings also show that adjacent states do not always share similar sentiment trends, and that geographic clusters with similar sentiment trends also vary across topics. Failing to consider these variations may result in misunderstanding public discourse and sentiments since they are diverse and dynamic in nature.
Heated gripper concept to optimize heat transfer of fiber-reinforced-thermoplastics in automated thermoforming processes
Creators: name: Bruns, Christopher
name: Bohne, Florian
name: Micke-Camuz, Moritz
name: Behrens, Bernd-Arno
name: Raatz, Annika
Publisher: name: Amsterdam : Elsevier B.V.
Year: 2019
Subjects: subject: finte-element-analysis
subject: forming
subject: heat transfer
subject: organo-sheet
subject: robot gripper
subject: Fiber reinforced plastics
subject: Forming
subject: Grippers
subject: Heat transfer
subject: Reinforcement
subject: Thermoforming
subject: Thermoplastics
subject: Element analysis
subject: Fabric deformations
subject: Fiber reinforced thermoplastics
subject: Lightweight application
subject: Robot gripper
subject: Simulation approach
subject: Temperature changes
subject: Reinforced plastics
subject: Konferenzschrift
subject: Dewey Decimal Classification::600 | Technik
subject: Dewey Decimal Classification::600 | Technik::670 | Industrielle und handwerkliche Fertigung

description: Today composite materials become increasingly more common to use for lightweight applications. This paper introduces a simulation approach for a handling and forming process. This process focusses on the robot based gripping, handling and forming of continuous-fiber-reinforced-thermoplastics, such as organo-sheet. The results of this paper show a manufacturing study of the heat transfer of a temperature-elevated organo-sheet during handling using heated needlegripper. Beside the fabric deformation, this research focuses on the temperature distribution during forming. Fast temperature drops lead to an increasing stiffness of the thermoplastic. Therefore, it is necessary to consider changing material parameters due to the temperature change. © 2019 The Author(s).
THE ISSUES OF TEACHING UZBEK STUDENTS ENGLISH
Creators: name: Yuldasheva, Dilnoza
Publisher: name: Zenodo
Year: 2024

description: This  thesis discusses the issues of teaching English in Uzbekistan and its methods, as well as tips for teaching effectiveness. It also highlights the importance of moving from a teacher-centered approach to teaching and learning English, and presents the results of an educational test aimed at creating a student-centered environment in the dialect classroom.
Constructing a Stochastic Model of Bumblebee Flights from Experimental Data
Creators: name: Lenz, Friedrich
name: Chechkin, Aleksei V.
name: Klages, Rainer
Publisher: name: arXiv
Year: 2013
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The movement of organisms is subject to a multitude of influences of widely varying character: from the bio-mechanics of the individual, over the interaction with the complex environment many animals live in, to evolutionary pressure and energy constraints. As the number of factors is large, it is very hard to build comprehensive movement models. Even when movement patterns in simple environments are analysed, the organisms can display very complex behaviours. While for largely undirected motion or long observation times the dynamics can sometimes be described by isotropic random walks, usually the directional persistence due to a preference to move forward has to be accounted for, e.g., by a correlated random walk. In this paper we generalise these descriptions to a model in terms of stochastic differential equations of Langevin type, which we use to analyse experimental search flight data of foraging bumblebees. Using parameter estimates we discuss the differences and similarities to correlated random walks. From simulations we generate artificial bumblebee trajectories which we use as a validation by comparing the generated ones to the experimental data.
description: Accepted for publication in PLoS ONE
Cosmic Background Bose Condensation (CBBC)
Creators: name: Alfonso-Faus, Antonio
name: Alfonso, Màrius Josep Fullana i
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: Degeneracy effects for bosons are more important for smaller particle mass, smaller temperature and higher number density. Bose condensation requires that particles be in the same lowest energy quantum state. We propose a cosmic background Bose condensation, present everywhere, whith its particles having the lowest quantum energy state, $\hbar c / λ$, with $λ$ about the size of the visible universe, and therefore unlocalized. This we identify with the quantum of the self gravitational potential energy of any particle, and with the bit of information of minimum energy. The entropy of the universe ($\sim 10^{122} \ bits$) has the highest number density ($ \sim 10^{36} \ bits / cm^3$) of particles inside the visible universe, the smallest mass, $\sim 10^{-66} g$, and the smallest temperature, $\sim 10^{-29} K$. Therefore it is the best candidate for a Cosmic Background Bose Condensation (CBBC), a completely calmed fluid, with no viscosity, in a superfluidity state, and possibly responsible for the expansion of the universe.
description: 14 pages. Accepted for publication in Astrophysics and Space Science. arXiv admin note: substantial text overlap with arXiv:1212.1711
Motional Fock states for quantum-enhanced amplitude and phase measurements with trapped ions
Creators: name: Wolf, Fabian
name: Shi, Chunyan
name: Heip, Jan C.
name: Gessner, Manuel
name: Pezzè, Luca
name: Smerzi, Augusto
name: Schulte, Marius
name: Hammerer, Klemens
name: Schmidt, Piet O.
Publisher: name: London : Nature Publishing Group
Year: 2019
Subjects: subject: quantum noise
subject: vacuum
subject: Motional Fock states
subject: Dewey Decimal Classification::500 | Naturwissenschaften

description: The quantum noise of the vacuum limits the achievable sensitivity of quantum sensors. In non-classical measurement schemes the noise can be reduced to overcome this limitation. However, schemes based on squeezed or Schrödinger cat states require alignment of the relative phase between the measured interaction and the non-classical quantum state. Here we present two measurement schemes on a trapped ion prepared in a motional Fock state for displacement and frequency metrology that are insensitive to this phase. The achieved statistical uncertainty is below the standard quantum limit set by quantum vacuum fluctuations, enabling applications in spectroscopy and mass measurements.
A large-scale study of the World Wide Web: network correlation functions with scale-invariant boundaries
Creators: name: Luduena, G. A.
name: Meixner, H.
name: Kaczor, Gregor
name: Gros, Claudius
Publisher: name: arXiv
Year: 2012
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Social and Information Networks (cs.SI)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: We performed a large-scale crawl of the World Wide Web, covering 6.9 Million domains and 57 Million subdomains, including all high-traffic sites of the Internet. We present a study of the correlations found between quantities measuring the structural relevance of each node in the network (the in- and out-degree, the local clustering coefficient, the first-neighbor in-degree and the Alexa rank). We find that some of these properties show strong correlation effects and that the dependencies occurring out of these correlations follow power laws not only for the averages, but also for the boundaries of the respective density distributions. In addition, these scale-free limits do not follow the same exponents as the corresponding averages. In our study we retain the directionality of the hyperlinks and develop a statistical estimate for the clustering coefficient of directed graphs. We include in our study the correlations between the in-degree and the Alexa traffic rank, a popular index for the traffic volume, finding non-trivial power-law correlations. We find that sites with more/less than about one Thousand links from different domains have remarkably different statistical properties, for all correlation functions studied, indicating towards an underlying hierarchical structure of the World Wide Web.
description: Includes degree and Alexa rank correlations
title: Köpfe und was dahinter steckt. Die Sonderausstellung »Horst Janssen. Das Portrait« im Germanischen Nationalmuseum Nürnberg vom 26. November 1998 bis zum 28. Februar 1999
Creators: name: Scherer, Annette
Publisher: name: University Library Heidelberg
Year: 2016

description: [nicht vorhanden / not available]
Influence of nitrogen in brazing atmospheres on the hardness of the microstructural constituents of brazed stainless steel joints
Creators: name: Fedorov, V.
name: Uhlig, T.
name: Wagner, G.
name: Langohr, A.
name: Holländer, U.
Publisher: name: Bristol : Institute of Physics Publishing
Year: 2019
Subjects: subject: Air conditioning
subject: Extraction
subject: Furnaces
subject: Hardness
subject: Heat treating furnaces
subject: Joints (structural components)
subject: Mechanical properties
subject: Metallurgical furnaces
subject: Microalloyed steel
subject: Nitrogen
subject: Oil field equipment
subject: Stainless steel
subject: Vacuum brazing
subject: Vacuum furnaces
subject: Air conditioning technologies
subject: Carrier gas hot extractions
subject: Continuous furnaces
subject: Micro-structural
subject: Nitrogen enrichment
subject: Process condition
subject: Stainless steel joints
subject: Steel components
subject: Brazing
subject: Konferenzschrift
subject: Dewey Decimal Classification::500 | Naturwissenschaften::530 | Physik

description: Stainless steel components, such as heat exchangers for energy and air-conditioning technologies are commonly manufactured using nickel-based brazing fillers in continuous furnaces or vacuum furnaces. In the continuous furnace, the brazing process is often supported by a protective gas. As protective gas is commonly used nitrogen or mixtures of nitrogen and hydrogen. In the vacuum furnace, nitrogen is often used as cooling gas. The arising nitrogen enrichment of the braze metal and the base material influences the mechanical properties of the microstructural constituents of the brazed joints, especially the hardness. In this work, the influence of the nitrogen enrichment on the hardness of the microstructural constituents of the joints was investigated with regard to the process conditions. The amount of nitrogen in the braze metal as well as in the base material was determined using a carrier gas hot extraction technique. The hardness of the microstructural constituents of the brazed joints was determined using nanoindentation due to their small size (few microns). The results of samples, brazed with and without the influence of nitrogen, were compared.
Coherent Storage of Temporally Multimode Light Using a Spin-Wave Atomic Frequency Comb Memory
Creators: name: Gündoğan, Mustafa
name: Mazzera, Margherita
name: Ledingham, Patrick M.
name: Cristiani, Matteo
name: de Riedmatten, Hugues
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We report on coherent and multi-temporal mode storage of light using the full atomic frequency comb memory scheme. The scheme involves the transfer of optical atomic excitations in Pr3+:Y2SiO5 to spin-waves in the hyperfine levels using strong single-frequency transfer pulses. Using this scheme, a total of 5 temporal modes are stored and recalled on-demand from the memory. The coherence of the storage and retrieval is characterized using a time-bin interference measurement resulting in visibilities higher than 80%, independent of the storage time. This coherent and multimode spin-wave memory is promising as a quantum memory for light.
description: 17 pages, 5 figures
The evolution of the global stellar mass function of star clusters: an analytic description
Creators: name: Lamers, Henny J. G. L. M.
name: Baumgardt, Holger
name: Gieles, Mark
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The evolution of the global stellar mass function (MF) of star clusters is studied based on a large set of N-body simulations of clusters with a range of initial masses, initial concentrations, in circular or elliptical orbits in different tidal environments. Models with and without initial mass segregation are included. The depletion of low mass stars in initially Roche-volume (tidal) filling clusters starts typically on a time scale of the order of the core collapse time. In clusters that are initially underfilling their Roche-volume it takes longer because the clusters have to expand to their tidal radii before dynamical mass loss becomes important. We introduce the concept of the differential mass function (DMF), which describes the changes with respect to the initial mass function (IMF). We show that the evolution of the DMF can be described by a set of very simple analytic expressions that are valid for a wide range of initial cluster parameters and for different IMFs. The agreement between this description and the models is very good, except for initially Roche-volume underfilling clusters that are severely mass segregated.
description: 12 pages, 8 figures, MNRAS in press
Extragalactic millimeter-wave point source catalog, number counts and statistics from 771 square degrees of the SPT-SZ Survey
Creators: name: Mocanu, L. M.
name: Crawford, T. M.
name: Vieira, J. D.
name: Aird, K. A.
name: Aravena, M.
name: Austermann, J. E.
name: Benson, B. A.
name: Béthermin, M.
name: Bleem, L. E.
name: Bothwell, M.
name: Carlstrom, J. E.
name: Chang, C. L.
name: Chapman, S.
name: Cho, H-M.
name: Crites, A. T.
name: de Haan, T.
name: Dobbs, M. A.
name: Everett, W. B.
name: George, E. M.
name: Halverson, N. W.
name: Harrington, N.
name: Hezaveh, Y.
name: Holder, G. P.
name: Holzapfel, W. L.
name: Hoover, S.
name: Hrubes, J. D.
name: Keisler, R.
name: Knox, L.
name: Lee, A. T.
name: Leitch, E. M.
name: Lueker, M.
name: Luong-Van, D.
name: Marrone, D. P.
name: McMahon, J. J.
name: Mehl, J.
name: Meyer, S. S.
name: Mohr, J. J.
name: Montroy, T. E.
name: Natoli, T.
name: Padin, S.
name: Plagge, T.
name: Pryke, C.
name: Rest, A.
name: Reichardt, C. L.
name: Ruhl, J. E.
name: Sayre, J. T.
name: Schaffer, K. K.
name: Shirokoff, E.
name: Spieler, H. G.
name: Spilker, J. S.
name: Stalder, B.
name: Staniszewski, Z.
name: Stark, A. A.
name: Story, K. T.
name: Switzer, E. R.
name: Vanderlinde, K.
name: Williamson, R.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present a point source catalog from 771 square degrees of the South Pole Telescope Sunyaev Zel'dovich (SPT-SZ) survey at 95, 150, and 220 GHz. We detect 1545 sources above 4.5 sigma significance in at least one band. Based on their relative brightness between survey bands, we classify the sources into two populations, one dominated by synchrotron emission from active galactic nuclei, and one dominated by thermal emission from dust-enshrouded star-forming galaxies. We find 1238 synchrotron and 307 dusty sources. We cross-match all sources against external catalogs and find 189 unidentified synchrotron sources and 189 unidentified dusty sources. The dusty sources without counterparts are good candidates for high-redshift, strongly lensed submillimeter galaxies. We derive number counts for each population from 1 Jy down to roughly 9, 5, and 11 mJy at 95, 150, and 220 GHz. We compare these counts with galaxy population models and find that none of the models we consider for either population provide a good fit to the measured counts in all three bands. The disparities imply that these measurements will be an important input to the next generation of millimeter-wave extragalactic source population models.
description: 23 pages, 8 figures, submitted to ApJ
Dynamic response of a single-electron transistor in the ac Kondo regime
Creators: name: Nguyen, Thanh Thi Kim
Publisher: name: arXiv
Year: 2012
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: A single-electron transistor (SET) in a magnetic field irradiated with microwaves is studied theoretically in non-equilibrium Kondo regime. The two fold effect of frequency--Ω--microwaves is considered as follows: the oscillations in the voltage with frequency Ωand in the coupling parameters with frequency Ω/p (p\in\mathbb{N}). We describe the system by the Kondo model at a specific point in the Toulouse limit. A non-perturbative technique is proposed, namely, the non-equilibrium Green's functions and physical observables are averaged over a period of 2πp/Ω. When the microwave irradiation is considered affecting only the voltage, one sees the Kondo satellites as stated in the previous studies. Moreover, the features of the differential conductance and magnetic susceptibility of a SET become richer when the Kondo couplings are considered oscillating on time. We obtain the satellite peak splitting. It explains the possibilities one can find in experimental results that the distance between peaks, which appear in the differential conductance -- magnetic amplitude characteristics G(H) or in the differential conductance -- dc voltage characteristics G(V_{dc}), can be smaller than \hbarΩ.
description: 12 pages, 5 figures
The universe evolution in exponential $F(R)$-gravity
Creators: name: Bamba, K.
name: Lopez-Revelles, A.
name: Myrzakulov, R.
name: Odintsov, S. D.
name: Sebastiani, L.
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: A generic feature of viable exponential $F(R)$-gravity is investigated. An additional modification to stabilize the effective dark energy oscillations during matter era is proposed and applied to two viable models. An analysis on the future evolution of the universe is performed. Furthermore, a unified model for early and late-time acceleration is proposed and studied.
description: Proceedings of QFTG2013, published in TSPU Bulletin 3 (128), 2012, n 13 p.19-24
Eigenvalue measurement of topologically protected edge states in split-step quantum walks
Creators: name: Nitsche, Thomas
name: Geib, Tobias
name: Stahl, Christoph
name: Lorz, Lennart
name: Cedzich, Christopher
name: Barkhofen, Sonja
name: Werner, Reinhard F
name: Silberhorn, Christine
Publisher: name: Bristol : Institute of Physics Publishing
Year: 2019
Subjects: subject: bulk-boundary correspondence
subject: decoupling
subject: quantum walks
subject: split-step
subject: symmetry protected edge states
subject: topological phenomena
subject: Eigenvalues and eigenfunctions
subject: Topology
subject: Edge state
subject: Quantum walk
subject: Split step
subject: Quantum theory
subject: Dewey Decimal Classification::500 | Naturwissenschaften::530 | Physik

description: We study topological phenomena of quantum walks by implementing a novel protocol that extends the range of accessible properties to the eigenvalues of the walk operator. To this end, we experimentally realise for the first time a split-step quantum walk with decoupling, which allows for investigating the effect of a bulk-boundary while realising only a single bulk configuration. The experimental platform is implemented with the well-established time-multiplexing architecture based on fibre-loops and coherent input states. The symmetry protected edge states are approximated with high similarities and we read-out the phase relative to a reference for all modes. In this way we observe eigenvalues which are distinguished by the presence or absence of sign flips between steps. Furthermore, the results show that investigating a bulk-boundary with a single bulk is experimentally feasible when decoupling the walk beforehand.
Hybrid cooling of the Cassiopeia A neutron star
Creators: name: Leinson, Lev B.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The observed rapid cooling of the neutron star Cassiopeia A is usually interpreted as being caused by transitions of neutrons and protons in the star's core from the normal state to the superfluid and superconducting state. However, this so-called "minimal" cooling paradigm faces the problem of numerically simulating the observed anomalously fast drop in the neutron star surface temperature using theoretical neutrino energy losses from superfluid neutrons. As a solution to this problem, I propose a somewhat more complex cooling model, in which, in addition to superfluid neutrons, direct Urca processes from a very small central part of the neutron star core are also involved. Numerical simulations of the cooling trajectory in this scenario show excellent agreement with observations of the Cassiopeia A neutron star. The proposed cooling scenario unambiguously relates the used equation of state and the mass of the neutron star. For a neutron star constructed according to BSk25 equation of state, the most appropriate are the mass $M=1.62M_{\sun}$ and the radius $R=12.36$ km. If BSk24 equation of state is used, then the most suitable solution is $M=1.60M_{\sun}$ and $R=12.55$ km.
description: 7 pages, 8 figures
Abundances determined using Si II and Si III in B-type stars: evidence for stratification
Creators: name: Bailey, Jeffrey D.
name: Landstreet, John D.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: It is becoming clear that determination of the abundance of Si using lines of Si II and Si III can lead to quite discordant results in mid to late B-type stars. The difference between the Si abundances derived from the two ion states can exceed one dex in some cases. We have carried out a study intended to clarify which kinds of B stars exhibit this discrepancy, to try to identify regularities in the phenomenon, and to explore possible explanations such as abundance stratification by comparing models to observed spectra. We used spectra from the ESPaDOnS spectropolarimeter and FEROS spectrograph, supplemented with spectra from the ESO and ELODIE archives, of magnetic Bp, HgMn, and normal B-type stars ranging in effective temperature from about 10500 to 15000 K. Using these spectra, we derived abundances using the spectrum synthesis program ZEEMAN which can take into account the influence of magnetic fields. For each star, accurate abundances of Si II, Si III, Ti, Cr, and Fe were derived. All magnetic Bp stars in our sample show a discordance between the derived abundances of the first and second ions of silicon, with the latter being between 0.6 - 1.7 dex higher. The same behaviour is observed in the non-magnetic stars but to a much smaller extent: Si III is enhanced by between 0.3 - 0.8 dex compared to Si II.We do not detect the discrepancy in three stars, HD 22136 (normal), HD 57608 (HgMn) and HD 27295 (HgMn); these are the only stars in our sample for which the microturbulence parameter is significantly different from zero, and which therefore probably have convection occurring in their atmospheres. We find that vertical stratification of silicon in the atmospheres of B-type stars may provide an explanation of this phenomenon, but our detailed stratification models do not completely explain the discrepancies, which may, in part, be due to non-LTE effects.
description: 9 pages, 2 figures, accepted for publication in A&A
Essays on the integration and implementation of a demographically oriented human resource management
Creators: name: Röhl, Maximilian Tim
Publisher: name: Hannover : Institutionelles Repositorium der Leibniz Universität Hannover
Year: 2019
Subjects: subject: strategic human resource management
subject: implementation
subject: typology
subject: demographic change
subject: strategisches Human Resource Management
subject: Integration
subject: Implementierung
subject: Typologie
subject: demografischer Wandel
subject: Dewey Decimal Classification::300 | Sozialwissenschaften, Soziologie, Anthropologie::330 | Wirtschaft

description: The current demographic developments in the Western world lead to a shrinking labor supply and an aging workforce. In order to cope with these changes, organizations need to find ways to maintain the motivation, commitment and productivity of older workers. Accordingly, there is an increasing body of literature that shows that organizations can address the challenges associated with demographic change through the use of age-appropriate human resource (HR) practices. However, even though research in the realm of strategic human resource management (SHRM) suggests that the effectiveness of these practices is significantly influenced by their integration into wider HR systems and implementation on the operational level, few studies have explored drivers of and barriers to a demographically oriented HRM. The aim of this dissertation is to address this gap and explore if and how HR-practices associated with demographic change are integrated and implemented. It consists of three individual research articles. The first article, a conceptual paper, builds on the concept of the psychological contract to develop a typology regarding the influence of SHRM on employees’ perceptions and reactions. It thereby contributes to a more holistic understanding of the way the integration, implementation and communication of HR-practices influence their effectiveness. The remaining two papers draw on a multiple case study conducted in four German organizations to provide deeper insights into the implementation and integration of demographically orientated HR-practices. Specifically, the second paper explores how the physical, social and task contexts influence the implementation effectiveness of these practices. Finally, the third paper explores how internal dynamics influence the fit and adaption of HR systems to demographic change. Together, these findings contribute to a more holistic and nuanced understanding of the way in which practices relating to demographic change are implemented and integrated. In addition, this dissertation helps to connect findings regarding demographically oriented HRM to the SHRM literature.
Teachers- Attitude to work on learners- study readiness in primary schools in Odukpani LGA of Cross River State, Nigeria.pdf
Creators: name: Edeh, Stephen  Olenye
Publisher: name: figshare
Year: 2023
Subjects: Professional education and training
Teacher education and professional development of educators

description: The purpose of this study was to find out influence of teachers’ attitudes to work on learners’ study readiness in primary schools in Odukpani local government area of cross river state, Nigeria. Two research questions and two null hypotheses were posed and formulated respectively to guide the study. Ex-post facto design was adopted for the study, purposive sampling technique was used to select 60 respondents (40 class teachers, 10 deputy head teachers and 10 head teachers) for the study...
Incidence of low-density meteoroids of the Polonnaruwa type
Creators: name: Wickramasinghe, N. C.
name: Wallis, J.
name: Wallis, D. H.
name: Wallis, M. K.
name: Miyake, N.
name: Coulson, S. G.
name: Gibson, Carl H.
name: Wickramasinghe, J. T.
name: Samaranayake, A.
name: Wickramarathne, K.
name: Hoover, Richard B.
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Physics (physics.gen-ph)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The ingress of micrometeorites of cometary origin with densities below ~ 1 g cm-3 into the Earth could average at least 5 tonne per day. Although much of this is burnt upon entry through the atmosphere as meteors, a non-trivial fraction (~10%) which have sizes of ~ 1 m could end up in the form of Polonnaruwa-type meteorites that have mostly gone unnoticed.
description: 8 pages, 5 figures
Ferromagnetism and Fermi-surface transition in the periodic Anderson model: Second-order phase transition without symmetry breaking
Creators: name: Kubo, Katsunori
Publisher: name: arXiv
Year: 2013
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study ferromagnetism in the periodic Anderson model with and without a magnetic field by the Gutzwiller theory. We find three ferromagnetic phases: a weak ferromagnetic phase (FM0), a half-metallic phase without Fermi surface for the majority spin (FM1), and a ferromagnetic phase with almost completely polarized f-electrons (FM2). The Fermi surface changes from the large Fermi-surface in the paramagnetic state to the small Fermi-surface in FM2. We also find that the transitions between the ferromagnetic phases can be second-order phase transitions in spite of the absence of symmetry breaking. While we cannot define an order parameter for such transitions in an ordinary way, the topology of the Fermi surface characterizes the transitions, i.e., they are Lifshitz transitions.
description: 10 pages, 8 figures
Coherent phonon manipulation in coupled mechanical resonators
Creators: name: Okamoto, Hajime
name: Gourgout, Adrien
name: Chang, Chia-Yuan
name: Onomitsu, Koji
name: Mahboob, Imran
name: Chang, Edward Yi
name: Yamaguchi, Hiroshi
Publisher: name: arXiv
Year: 2012
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Coupled mechanical oscillations were first observed in paired pendulum clocks in the mid-seventeenth century and were extensively studied for their novel sympathetic oscillation dynamics. In this era of nanotechnologies, coupled oscillations have again emerged as subjects of interest when realized in nanomechanical resonators for both practical applications and fundamental studies. However, a key obstacle to the further development of this architecture is the ability to coherently manipulate the coupled oscillations. This limitation arises as a consequence of the usually weak coupling between the constituent nanomechanical elements. Here, we report parametrically coupled mechanical resonators in which the coupling strength can be dynamically adjusted by modulating (pumping) the stress in the mechanical elements via a piezoelectric transducer. The parametric control enables the coupling rate between the two resonators to be made so strong that it exceeds their intrinsic energy dissipation rate by more than a factor of four. This ultra-strong coupling can be exploited to coherently transfer phonon populations, namely phonon Rabi oscillations, between the resonators via two coupled vibration modes, realizing superposition states of the two modes and their time-domain control. More unexpectedly, the nature of the parametric coupling can also be tuned from a linear first-order interaction to a non-linear higher-order process in which more than one pump phonon mediates the coherent oscillations. This demonstration of multi-pump phonon mixing echoes multi-wave photon mixing and suggests that concepts from non-linear optics can also be applied to mechanical systems. Ultimately, the parametric pumping is not only useful for controlling classical oscillations but can also be extended to the quantum regime, opening up the prospect of entangling two distinct macroscopic mechanical objects.
description: 16 pages, 11 figures
Explanation for the smoothness of the phase in molecular high-order harmonic generation
Creators: name: Chirilä, C.C.
name: Lein, Manfred
Publisher: name: College Park, MD : American Physical Society
Year: 2009
Subjects: subject: Coulomb effects
subject: Electron motion
subject: Harmonic amplitude
subject: High order harmonic generation
subject: Laser polarization
subject: Lewenstein model
subject: Orientation dependence
subject: Phase jumps
subject: Saddle-point approximation
subject: Dewey Decimal Classification::500 | Naturwissenschaften::530 | Physik

description: We analyze the orientation dependence of harmonic amplitudes and phases from laser driven H2+. We use the Lewenstein model, with and without employing the saddle-point approximation for the summation over electron momenta. This means that the direction of the electron motion is not necessarily restricted to the laser polarization axis in contrast to previous implementations. The model predicts smooth phase jumps by almost π in the orientation dependence. This demonstrates that the smoothness can be explained without Coulomb effects, but these may be relevant for the size of the phase jumps observed in recent experiments. © 2009 The American Physical Society