cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Fuchs versus Painlevé
Creators: name: Boukraa, S.
name: Hassani, S.
name: Maillard, J. -M.
name: McCoy, B. M.
name: Weil, J. -A.
name: Zenine, N.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 33E17, 33E05, 33Cxx, 33Dxx, 14Exx, 14Hxx, 34M55, 47E05, 34Lxx, 34Mxx, 14Kxx

description: We briefly recall the Fuchs-Painlevé elliptic representation of Painlevé VI. We then show that the polynomiality of the expressions of the correlation functions (and form factors) in terms of the complete elliptic integral of the first and second kind, $ K$ and $ E$, is a straight consequence of the fact that the differential operators corresponding to the entries of Toeplitz-like determinants, are equivalent to the second order operator $ L_E$ which has $ E$ as solution (or, for off-diagonal correlations to the direct sum of $ L_E$ and $ d/dt$). We show that this can be generalized, mutatis mutandis, to the anisotropic Ising model. The singled-out second order linear differential operator $ L_E$ being replaced by an isomonodromic system of two third-order linear partial differential operators associated with $ Π_1$, the Jacobi's form of the complete elliptic integral of the third kind (or equivalently two second order linear partial differential operators associated with Appell functions, where one of these operators can be seen as a deformation of $ L_E$). We finally explore the generalizations, to the anisotropic Ising models, of the links we made, in two previous papers, between Painlevé non-linear ODE's, Fuchsian linear ODE's and elliptic curves. In particular the elliptic representation of Painlevé VI has to be generalized to an ``Appellian'' representation of Garnier systems.
description: Dedicated to the : Special issue on Symmetries and Integrability of Difference Equations, SIDE VII meeting held in Melbourne during July 2006
Eccentric kinetic chain exercise as a conservative means of functionally rehabilitating chronic isolated cruciate ligament insuffiency
Creators: name: MacLean, Christopher Lawrence
Publisher: name: University of British Columbia
Year: 2009

description: Chronic, isolated posterior cruciate ligament (PCL) insufficiency can present several complications including patellofemoral pain, difficulty with stair descent and sudden changes in direction. The purpose of the present study was to develop a home, eccentric kinetic chain exercise program that improves strength, function and symptomatology. Thirteen, isolated posterior cruciate ligament (PCL) injured subjects and thirteen, healthy sedentary individuals were included in the study. The PCL group underwent 12 weeks of prescribed eccentric squat exercise. The healthy, sedentary group did not undergo exercise intervention. Both groups executed: the Tegner Hop Test, Lysholm Knee Scale Score and Kinetic Communicator isokinetic testing. All tests were administered at 0, 6, and 12-weeks of the investigation. Four relationships were explored to analyze the effectiveness of the "eccentric rehabilitation program and to define significant differences (p<0.05) between healthy and PCL-injured subjects. Subject X Treatment data analysis clearly indicated that there were significant increases in eccentric quadricep and hamstring torque over the twelve week period. Tegner Hop Test and Lysholm Knee Scale scores also increased significantly following the eccentric squat program. Quadricep, eccentric/concentric ratios (@ 60 & 120 degrees per second) increased significantly after twelve weeks of rehabilitation. Significant strength differences did not exist between either extremity in the PCL group at any time throughout the course of this study. Prior to rehabilitation, there were no significant differences between eccentric and concentric torque values in the quadriceps, or hamstrings, of the PCL-injured group. Following the eccentric squat program, the injured extremity, quadriceps did exhibit a significantly greater eccentric torque than concentric torque. The PCL group was significantly weaker than the control group in quadriceps, eccentric torque (@60 & 120 degrees per second), at week 0. The 12-week program resulted in there being no significant differences between PCL and control groups in eccentric, quadriceps torque. The results of this investigation strongly support the eccentric squat program as a viable means of functionally rehabilitating chronic PCL-insufficiency with eccentric kinetic chain exercise.
Horizon-less Spherically Symmetric Vacuum-Solutions in a Higgs Scalar-Tensor Theory of Gravity
Creators: name: Bezares-Roder, Nils M.
name: Nandan, Hemwati
name: Dehnen, Heinz
Publisher: name: arXiv
Year: 2006
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The exact static and spherically symmetric solutions of the vacuum field equations for a Higgs Scalar-Tensor theory (HSTT) are derived in Schwarzschild coordinates. It is shown that in general there exists no Schwarzschild horizon and that the fields are only singular (as naked singularity) at the center (i.e. for the case of a pont-particle). However, the Schwarzschild solution as in usual general relativity (GR) is obtained for the vanishing limit of Higgs field excitations.
description: 5 pages, 0 figures. Changed to final version in journal The original publication is available at http://www.springer.com
Influence of lunisolar tides on plants. Parametric resonance induced by periodic variations of gravity
Creators: name: Gouin, Henri
Publisher: name: arXiv
Year: 2020
Subjects: subject: Classical Physics (physics.class-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Recent experiments conducted in the International Space Station highlight the apparent periodicity of leaf oscillations and other biological phenomena associated with rhythmic variations of lunisolar forces. These events are similar to those occurring on Earth, but with greater effects over a shorter period of time. Among the possible disturbances, other than forced or self-existing oscillations, parametric resonances appear caused by a small periodic term; such is the case of fluids subjected to small periodic variations in gravitational forces in microscopic or mesoscopic plant channels filled with sap and air-vapor. The interface instabilities verify a Mathieu's second order differential equation resulting from a Rayleigh-Taylor stability model. These instabilities appear during the Moon's rotation around the Earth and during the revolution of the International Space Station. They create impulses of pressure and sap movements in the network of roots, stems and leaves. The model can explain the effects of the lunar tide on plant growth. The eccentricity of the lunar orbit around the Earth creates an important difference between the apogee and perigee of the Moon's trajectory and therefore the tidal effects can depend on the distance between the Moon and the Earth.
Cometary records revise Eastern Mediterranean chronology around 1240 CE
Creators: name: Murata, Koji
name: Ichikawa, Kohei
name: Fujii, Yuri I.
name: Hayakawa, Hisashi
name: Cheng, Yongchao
name: Kawamoto, Yukiko
name: Sano, Hidetoshi
Publisher: name: arXiv
Year: 2020
Subjects: subject: History and Philosophy of Physics (physics.hist-ph)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Popular Physics (physics.pop-ph)
subject: FOS: Physical sciences

description: Eirene Laskarina, empress of John III Batatzes of the exiled Byzantine Empire of Nicaea (1204--1261 CE), was an important Eastern Mediterranean figure in the first half of the thirteenth century. We reassess the date of Eirene's death, which has been variously dated between late 1239 and 1241, with the understanding that narrowing the range in which this event occurred contributes much to understanding the political situation in the area around 1240. George Akropolites, a famous official of the Empire, gives an account that connects Eirene's death to a comet that appeared "six months earlier", thus pointing to two comet candidates that were visible from the Eastern Mediterranean between 1239 and 1241, one recorded on "3 June 1239" and the other on "31 January 1240". Recent historians prefer the former, based on historical circumstances and without a critical assessment of the comet records. We revisit the historical records and reveal that the "3 June 1239" candidate was not a comet. On the other hand, the other candidate, sighted on "31 January 1240", was a comet, as supported by multiple historical records in multiple regions, and is also a good fit with Akropolites's narrative. Therefore, we conclude that Eirene died six months after the comet that was seen on 31 January 1240, which places her death in the summer of 1240. Given that the date of her death is crucial for determining some other contemporary events across the Eastern Mediterranean, our results offer a solid basis for further research on the thirteenth-century Eastern Mediterranean.
description: 14 pages, 3 figures, accepted for publication in PASJ
Welsh Wreck Web Research Project (North Cardigan Bay). On-line research into the Grounding of: Prosperity (Schooner)
Creators: name: Davies, Gareth J.S.
Publisher: name: Archaeology Data Service
Year: 2024

description: Welsh Wreck Web Research Project unpublished report series, 1
description: The Prosperity was a wooden cargo schooner which sailed predominately between U.K. ports on the Irish Sea, Ireland, Scotland, N.E. England, S.W England, E. England, N.W Europe and Iberian ports. Cargos carried included slates, coal, salt, pig iron, cement, grains and other general cargos. On Dec 14 th 1909, the Prosperity after dragging her anchor collided with the schooner Unity and was damaged. The crew of 7 was rescued by the Abersoch Lifeboat. Although reported as likely to be a wreck the Prosperity was salvaged.
Mutual Teaching for Graph Convolutional Networks
Creators: name: Zhan, Kun
name: Niu, Chaoxi
Publisher: name: arXiv
Year: 2020
Subjects: subject: Machine Learning (cs.LG)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Graph convolutional networks produce good predictions of unlabeled samples due to its transductive label propagation. Since samples have different predicted confidences, we take high-confidence predictions as pseudo labels to expand the label set so that more samples are selected for updating models. We propose a new training method named as mutual teaching, i.e., we train dual models and let them teach each other during each batch. First, each network feeds forward all samples and selects samples with high-confidence predictions. Second, each model is updated by samples selected by its peer network. We view the high-confidence predictions as useful knowledge, and the useful knowledge of one network teaches the peer network with model updating in each batch. In mutual teaching, the pseudo-label set of a network is from its peer network. Since we use the new strategy of network training, performance improves significantly. Extensive experimental results demonstrate that our method achieves superior performance over state-of-the-art methods under very low label rates.
description: GCN, 8 pages, 1 figures
Welsh Wreck Web Research Project (North Cardigan Bay). On-line research into the wreck of the: SS Pulteney
Creators: name: Davies, Gareth J.S.
Publisher: name: Archaeology Data Service
Year: 2024

description: Welsh Wreck Web Research Project unpublished report series, 1
description: The SS Pulteney was a small coastal cargo steamship built in Troon, Scotland as the SS Barrow Castle and commissioned in 1899. The SS Pulteney sailed largely in the Irish Sea carrying coal between NW England, Wales and SW England. In August 1934, in poor visibility the SS Pulteney collided with another coastal steamship the SS Thelma off Bardsey Island, Caernarfonshire and sank within 15 mins with no loss of life.
The $H_3^+$ molecular ion in a magnetic field in linear parallel configuration
Creators: name: Turbiner, A. V.
name: Guevara, N. L.
name: Vieyra, J. C. López
Publisher: name: arXiv
Year: 2006
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Astrophysics (astro-ph)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: A first detailed study of the ground state of the H$_3^+$ molecular ion in linear configuration, parallel to a magnetic field direction, and its low-lying $\Si,Π,\De$ states is carried out for magnetic fields $B=0-4.414 \times 10^{13} $G in the Born-Oppenheimer approximation. The variational method is employed with a single trial function which includes electronic correlation in the form $\exp{(\ga r_{12})}$, where $\ga$ is a variational parameter. It is shown that the quantum numbers of the state of the lowest total energy (ground state) depend on the magnetic field strength. The ground state evolves from the spin-singlet ${}^1\Si_g$ state for weak magnetic fields $B \lesssim 5 \times 10^{8} $G to a weakly-bound spin-triplet ${}^3\Si_u$ state for intermediate fields and, eventually, to a spin-triplet $^3Π_u$ state for $5 \times 10^{10} \lesssim B \lesssim 4.414 \times 10^{13} $G. Local stability of the linear parallel configuration with respect to possible small deviations is checked.
description: 27 pages, 6 figures, 12 tables (the text expanded, several new references added, typos corrected)
Molecular aggregation in liquid water: Laplace spectra and spectral clustering of H-bonded network
Creators: name: Bakó, Imre
name: Csókás, Dániel
name: Pothoczki, Szilvia
Publisher: name: arXiv
Year: 2020
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: Application of the spectral clustering method based on the analyses of the Laplace matrix is an acceptable indicator of the global properties of H-bonded network. The first peak of the Laplace spectra contains six eigenvalues. These results suggest that six communities are always formed in our simulated systems independently of the number of molecules in the cubic box. We showed that the H-bonded environment on the surface of the clusters is different from what can be found inside of the clusters. The fraction of four-coordinated molecules is significantly larger in the case of surface molecules. Our work emphasizes that the periodic boundary conditions always cause clustering in the system.
Quasar Detection using Linear Support Vector Machine with Learning From Mistakes Methodology
Creators: name: Herle, Aniruddh
name: Channegowda, Janamejaya
name: Prabhu, Dinakar
Publisher: name: arXiv
Year: 2020
Subjects: subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: The field of Astronomy requires the collection and assimilation of vast volumes of data. The data handling and processing problem has become severe as the sheer volume of data produced by scientific instruments each night grows exponentially. This problem becomes extensive for conventional methods of processing the data, which was mostly manual, but is the perfect setting for the use of Machine Learning approaches. While building classifiers for Astronomy, the cost of losing a rare object like supernovae or quasars to detection losses is far more severe than having many false positives, given the rarity and scientific value of these objects. In this paper, a Linear Support Vector Machine (LSVM) is explored to detect Quasars, which are extremely bright objects in which a supermassive black hole is surrounded by a luminous accretion disk. In Astronomy, it is vital to correctly identify quasars, as they are very rare in nature. Their rarity creates a class-imbalance problem that needs to be taken into consideration. The class-imbalance problem and high cost of misclassification are taken into account while designing the classifier. To achieve this detection, a novel classifier is explored, and its performance is evaluated. It was observed that LSVM along with Ensemble Bagged Trees (EBT) achieved a 10x reduction in the False Negative Rate, using the Learning from Mistakes methodology.
description: Published in 2020 IEEE International Conference on Electronics, Computing and Communication Technologies (CONECCT)
Nitrogen Atmospheres of the Icy Bodies in the Solar System
Creators: name: Scherf, M.
name: Lammer, H.
name: Erkaev, N. V.
name: Mandt, K. E.
name: Thaller, S. E.
name: Marty, B.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: This brief review will discuss the current knowledge on the origin and evolution of the nitrogen atmospheres of the icy bodies in the solar system, particularly of Titan, Triton and Pluto. An important tool to analyse and understand the origin and evolution of these atmospheres can be found in the different isotopic signatures of their atmospheric constituents. The $^{14}$N/$^{15}$N ratio of the N$_2$-dominated atmospheres of these bodies serve as a footprint of the building blocks from which Titan, Triton and Pluto originated and of the diverse fractionation processes that shaped these atmospheres over their entire evolution. Together with other measured isotopic and elemental ratios such as $^{12}$C/$^{13}$C or Ar/N these atmospheres can give important insights into the history of the icy bodies in the solar system, the diverse processes that affect their N$_2$-dominated atmospheres, and the therewith connected solar activity evolution. Titan's gaseous envelope most likely originated from ammonia ices with possible contributions from refractory organics. Its isotopic signatures can yet be seen in the - compared to Earth - comparatively heavy $^{14}$N/$^{15}$N ratio of 167.7, even though this value slightly evolved over its history due to atmospheric escape and photodissociation of N$_2$. The origin and evolution of Pluto's and Triton's tenuous nitrogen atmospheres remain unclear, even though it might be likely that their atmospheres originated from the protosolar nebula or from comets. An in-situ space mission to Triton such as the recently proposed Trident mission, and/or to the ice giants would be a crucial cornerstone for a better understanding of the origin and evolution of the icy bodies in the outer solar system and their atmospheres in general.
description: 60 pages, 6 figures. This is a preprint of an article published in Space Science Reviews. The final authenticated version can be found online at : https://doi.org/10.1007/s11214-020-00752-0
Canonical wave packets in quantum cosmology
Creators: name: Gousheh, S. S.
name: Sepangi, H. R.
name: Pedram, P.
name: Mirzaei, M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We discuss the construction of wave packets resulting from the solutions of a class of Wheeler-DeWitt equations in Robertson-Walker type cosmologies, for arbitrary curvature. We show that there always exists a ``canonical initial slope" for a given initial wave function, which optimizes some desirable properties of the resulting wave packet, most importantly good classical-quantum correspondence. This can be properly denoted as a canonical wave packet. We introduce a general method for finding these canonical initial slopes which is generalization of our earlier work.
description: 19 pages, 8 figures
The Rise and Emergence of Untwisted Toroidal Flux Ropes on the Sun
Creators: name: Knizhnik, Kalman J.
name: Leake, James E.
name: Linton, Mark G.
name: Dacie, Sally
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Magnetic flux ropes (MFRs) rising buoyantly through the Sun's convection zone are thought to be subject to viscous forces preventing them from rising coherently. Numerous studies have suggested that MFRs require a minimum twist in order to remain coherent during their rise. Furthermore, even MFRs that get to the photosphere may be unable to successfully emerge into the corona unless they are at least moderately twisted, since the magnetic pressure gradient needs to overcome the weight of the photospheric plasma. To date, however, no lower limit has been placed on the critical minimum twist required for an MFR to rise coherently through the convection zone or emerge through the photosphere. In this paper, we simulate an untwisted toroidal MFR which is able to rise from the convection zone and emerge through the photosphere as an active region that resembles those observed on the Sun. We show that untwisted MFRs can remain coherent during their rise and then pile-up near the photosphere, triggering the undular instability, allowing the MFR to emerge through the photosphere. We propose that the toroidal geometry of our MFR is critical for its coherent rise. Upon emerging, a pair of lobes rises into the corona which interact and reconnect, resulting in a localized high speed jet. The resulting photospheric magnetogram displays the characteristic salt-and-pepper structure often seen in observations. Our major result is that MFRs need not be twisted to rise coherently through the convection zone and emerge through the photosphere.
description: Accepted to ApJ
Η διαχείριση της ετερότητας στο Σχολικό συγκρότημα Επισκοπής Σαντορίνης Μελέτη Περίπτωσης
Creators: name: Παπαδοπούλου, Ιωάννα Σοφοκλή
Publisher: name: Aristotle University of Thessaloniki
Year: 2013
Subjects: Διαχείριση
Ετερότητα
Μελέτη Περίπτωσης
Management
Diversity
Case study

description: Σκοπός της παρούσας εργασίας ήταν η μελέτη περίπτωσης του σχολικού συγκροτήματος Επισκοπής Σαντορίνης. Αυτό που επιδιώχθηκε ήταν να ερευνηθεί η διαχείριση της ετερότητας στη τάξη στο νηπιαγωγείο και στο δημοτικό και ο τρόπος που οι εκπαιδευτικοί λειτουργούν όταν βρίσκονται σε ένα πολυπολιτισμικό περιβάλλον. Αρχικά στο πρώτο μέρος της εργασίας ερευνήθηκαν θεωρητικά οι παράγοντες που επηρεάζουν τον τρόπο που οι εκπαιδευτικοί λειτουργούν σε συνθήκες πολυπολιτισμικότητας στη τάξη και αυτοί σχετίζονται με το αναλυτικό πρόγραμμα και τις διδακτικές μεθόδους, τις στερεοτυπικές αντιλήψεις των εκπαιδευτικών, την επιμόρφωση των εκπαιδευτικών, την συνεργασία σχολείου οικογένειας καθώς και την αναγνώριση του μορφωτικού κεφαλαίου των αλλόφωνων μαθητών. Στη συνέχεια παρουσιάστηκαν τα ερευνητικά αποτελέσματα που προέκυψαν με βάση τις συνεντεύξεις που δόθηκαν από τους εκπαιδευτικούς του δείγματος και στηρίχθηκαν σε συγκεκριμένους άξονες που αφορούσαν το αναλυτικό πρόγραμμα και τις διδακτικές μεθόδους, τις στερεοτυπικές αντιλήψεις των εκπαιδευτικών, την επιμόρφωση των εκπαιδευτικών, την συνεργασία σχολείου οικογένειας καθώς και την αναγνώριση του μορφωτικού κεφαλαίου των αλλόφωνων μαθητών.
description: The purpose of this research was the case study in the school of Episkopi Santorini. What was sought was to be investigated the management of diversity in the classroom in kindergarten and primary school and the way that teachers operate when they are in a multicultural environment. Initially in the first part of the research was investigated theoretically the factors that influence the way that teachers work in multi-cultural conditions and they relate to the curriculum and teaching methods, stereotypical perceptions of teachers, training of teachers, school family cooperation and the recognition of the educational capital of allophone students. Then presented the research results which was based on the interviews the teachers gave and relied on specific thematics concerning the curriculum and teaching methods, stereotypical perceptions of teachers, training of teachers, family and school collaboration and recognition of the educational capital of allophone students
The boulder population of asteroid 4 Vesta: Size-frequency distribution and survival time
Creators: name: Schröder, Stefan E.
name: Carsenty, Uri
name: Hauber, Ernst
name: Schulzeck, Franziska
name: Raymond, Carol A.
name: Russell, Christopher T.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Dawn's framing camera observed boulders on the surface of Vesta when the spacecraft was in its lowest orbit (LAMO). We identified, measured, and mapped boulders in LAMO images, which have a scale of 20 m per pixel. We estimate that our sample is virtually complete down to a boulder size of 4 pixels (80 m). The largest boulder is a 400 m-sized block on the Marcia crater floor. Relatively few boulders reside in a large area of relatively low albedo, surmised to be the carbon-rich ejecta of the Veneneia basin, either because boulders form less easily here or live shorter. By comparing the density of boulders around craters with a known age, we find that the maximum boulder lifetime is about 300 Ma. The boulder size-frequency distribution (SFD) is generally assumed to follow a power law. We fit power laws to the Vesta SFD by means of the maximum likelihood method, but they do not fit well. Our analysis of power law exponents for boulders on other small Solar System bodies suggests that the derived exponent is primarily a function of boulder size range. The Weibull distribution mimics this behavior and fits the Vesta boulder SFD well. The Weibull distribution is often encountered in rock grinding experiments, and may result from the fractal nature of cracks propagating in the rock interior. We propose that, in general, the SFD of particles (including boulders) on the surface of small bodies follows a Weibull distribution rather than a power law.
Spiral wave chimeras in reaction-diffusion systems: phenomenon, mechanism and transitions
Creators: name: Li, Bing-Wei
name: He, Yuan
name: Li, Ling-Dong
name: Yang, Lei
name: Wang, Xingang
Publisher: name: arXiv
Year: 2020
Subjects: subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: Spiral wave chimeras (SWCs), which combine the features of spiral waves and chimera states, are a new type of dynamical patterns emerged in spatiotemporal systems due to the spontaneous symmetry breaking of the system dynamics. In generating SWC, the conventional wisdom is that the dynamical elements should be coupled in a nonlocal fashion. For this reason, it is commonly believed that SWC is excluded from the general reaction-diffusion (RD) systems possessing only local couplings. Here, by an experimentally feasible model of three-component FitzHugh-Nagumo-type RD system, we demonstrate that, even though the system elements are locally coupled, stable SWCs can still be observed in a wide region in the parameter space. The properties of SWCs are explored, and the underlying mechanisms are analyzed from the point view of coupled oscillators. Transitions from SWC to incoherent states are also investigated, and it is found that SWCs are typically destabilized in two scenarios, namely core breakup and core expansion. The former is characterized by a continuous breakup of the single asynchronous core into a number of small asynchronous cores, whereas the latter is featured by the continuous expansion of the single asynchronous core to the whole space. Remarkably, in the scenario of core expansion, the system may develop into an intriguing state in which regular spiral waves are embedded in a completely disordered background. This state, which is named shadowed spirals, manifests from a new perspective the coexistence of incoherent and coherent states in spatiotemporal systems, generalizing therefore the traditional concept of chimera states. Our studies provide an affirmative answer to the observation of SWCs in RD systems, and pave a way to the realization of SWCs in experiments.
description: 16 pages, 11 figures
Hudson's Theorem for finite-dimensional quantum systems
Creators: name: Gross, D.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We show that, on a Hilbert space of odd dimension, the only pure states to possess a non-negative Wigner function are stabilizer states. The Clifford group is identified as the set of unitary operations which preserve positivity. The result can be seen as a discrete version of Hudson's Theorem. Hudson established that for continuous variable systems, the Wigner function of a pure state has no negative values if and only if the state is Gaussian. Turning to mixed states, it might be surmised that only convex combinations of stabilizer states give rise to non-negative Wigner distributions. We refute this conjecture by means of a counter-example. Further, we give an axiomatic characterization which completely fixes the definition of the Wigner function and compare two approaches to stabilizer states for Hilbert spaces of prime-power dimensions. In the course of the discussion, we derive explicit formulas for the number of stabilizer codes defined on such systems.
description: 17 pages, 3 figures; References updated. Title changed to match published version. See also quant-ph/0702004
Film coating by directional droplet spreading on fibers
Creators: name: Chan, Tak Shing
name: Lee, Carmen L.
name: Pedersen, Christian
name: Dalnoki-Veress, Kari
name: Carlson, Andreas
Publisher: name: arXiv
Year: 2020
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Plants and insects use slender conical structures to transport and collect small droplets, which are propelled along the conical structures due to capillary action. These droplets can deposit a fluid film during their motion, but despite its importance to many biological systems and industrial applications the properties of the deposited film are unknown. We characterise the film deposition by developing an asymptotic analysis together with experimental measurements and numerical simulations based on the lubrication equation. We show that the deposited film thickness depends significantly on both the fiber radius and the droplet size, highlighting that the coating is affected by finite size effects relevant to film deposition on fibres of any slender geometry. We demonstrate that by changing the droplet size, while the mean fiber radius and the Capillary number are fixed, the thickness of the deposited film can change by an order of magnitude or more. We show that self-propelled droplets have significant potential to create passively coated structures.
Two-mode excited entangled coherent states and their entanglement properties
Creators: name: Zhou, Dong-Lin
name: Kuang, Le-Man
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We introduce two types of two-mode excited entangled coherent states (TMEECSs) $|Ψ_{\pm}(α,m,n)>$, study their entanglement characteristics, and investigate the influence of photon excitations on quantum entanglement. It is shown that for the state $|Ψ_{+}(α,m,n)>$ the two-mode photon excitations affect seriously entanglement character while the the state $|Ψ_{-}(α,m,n)>$ is always a maximally entangled state. We show how such states can be produced by using cavity QED and quantum measurements. It is found that the entanglement amount of the TMEECSs is larger than that of the single-mode excited entangled coherent states with the same photon excitation number.
description: 5 pages, no figure. v2: Revised version with corrections in equations and discussions
Απόψεις σχολικών συμβούλων προσχολικής εκπαίδευσης για το επιμορφωτικό τους έργο
Creators: name: Μπακαλοπούλου, Φωτεινή Σωτηρίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Σχολικοί σύμβουλοι
Επιμόρφωση
Προσχολική εκπαίδευση
Εκπαιδευτική πολιτική
School advisors
In service training
Preschool education
Educational policy

description: Σκοπός της ερευνητικής εργασίας ήταν να διερευνηθεί η προσωπική, κοινωνική και επαγγελματική διάσταση των απόψεων των σχολικών συμβούλων προσχολικής εκπαίδευσης για το επιμορφωτικό τους έργο. Αποσαφηνίστηκε και παρουσιάστηκε η ποικιλία των κατευθύνσεων του όρου ‘‘επιμόρφωση’’, η επιμόρφωση ως σύγχρονη ανάγκη της συνεχιζόμενης επαγγελματικής εκπαίδευσης και ανάπτυξης των εκπαιδευτικών καθώς και το επιμορφωτικό έργο των σχολικών συμβούλων σε σχέση με το θεσμικό πλαίσιο που το καθορίζει, αλλά και σε σχέση με τους προβληματισμούς που έχουν αναπτυχθεί για αυτό. Η ανάλυση του υλικού της έρευνας και η συζήτηση των διαπιστώσεων στηρίχτηκε στην ποιοτική ανάλυση περιεχομένου των απόψεων σχολικών συμβούλων προσχολικής εκπαίδευσης κυρίως από την Περιφέρεια της Κεντρικής Μακεδονίας, αλλά και της Θεσσαλίας.
description: The purpose of the research study was to investigate the personal, social and professional dimension of views of school pre-school advisers for their educational work. Clarified and presented the variety of the directions of the term ''in service training'', in service training as a modern necessity of continuing professional education and development of teachers and the educational work of the school advisors in connection with the institutional framework that defines it, but also in relation with the concerns that have been developed for it. The analysis of the material research and discussion of the findings relied on qualitative content analysis of the views of school preschool education consultants mainly from the Region of Central Macedonia and Thessaly.
Έρευνα δηλωμένων προτιμήσεων για τη λειτουργία συστήματος αστικής συγκοινωνίας με μικρά λεωφορεία στο Δήμο Καλαμαριάς.
Creators: name: Ακριώτη, Μαρία Ανέστη
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Έρευνα Δηλωμένων προτιμήσεων
Δημοτική αστική συγκοινωνία
Μικρά λεωφορεία
Stated Preference survey
public transport
mini bus

description: Η παρούσα Μεταπτυχιακή Διπλωματική Εργασία με τίτλο «Έρευνα δηλωμένων προτιμήσεων για την λειτουργία συστήματος αστικής συγκοινωνίας με μικρά λεωφορεία στο Δήμο Καλαμαριάς» εκπονήθηκε στα πλαίσια του μεταπτυχιακού προγράμματος σπουδών με τίτλο: "Τεχνικές μέθοδοι στην ανάλυση, σχεδίασμό και διαχείριση του χώρου" της κατεύθυνσης "Οργάνωση και διαχείριση πόρων και έργων ανάπτυξης". Το περιεχόμενο της Μεταπτυχιακής Διπλωματικής Εργασίας αφορά στη διερεύνηση του βαθμού αποδοχής ενός συστήματος με μικρά λεωφορεία στο Δήμο Καλαμαριάς, σε περίπτωση επαναλειτουργίας της δημοτικής συγκοινωνίας του Δήμου Καλαμαριάς. Με απώτερο στόχο τη διερεύνηση- αξιολόγηση του καταργηθέντος συστήματος και τη διατύπωση τεκμηριωμένης πρότασης επαναλειτουργίας της Δημοτικής Συγκοινωνίας του Δήμου Καλαμαριάς, κρίθηκε απαραίτητη σε πρώτο στάδιο, η καταγραφή των προθέσεων, των προτιμήσεων και των απόψεων των μετακινούμενων. Για τον λόγο αυτό, εκπονήθηκε Έρευνα Δηλωμένων Προτιμήσεων με τη χρήση κατάλληλα διαμορφωμένου ερωτηματολογίου. Συνολικά συλλέχθηκαν 140 έγκυρα ερωτηματολόγια. Η ανάλυση πραγματοποιήθηκε με τη βοήθεια περιγραφικής και επαγωγικής στατιστικής.
description: The present Postgraduate Diploma Thesis with the title: «Stated preference survey for the operation of an urban public transport system in the Municipality of Kalamaria» was carried out in the framework of the Postgraduate Programme Study: «Techniques and Methods for Spatial Analysis, Planning and Management, specialitation: organization and Management of Resources and Development Projects.» The content of the Postgraduate Diploma Thesis has to do with the investigation of the degree of acceptance for a mini- bus system in the Municipality of Kalamaria in case that the municipal urban trasport will be operational again. It was conidered necessary, at a first stage, to record the intentions, preferences and views at the trip makers in order to investigate and evaluate the former mini-bus system and also to formulate a proposal for a new operation of the municipal urban public transport system in the municipality of Kalamaria. For this purpose, a stated preference survey using a special questionnaire was carried out. A total number of 140 questionnaires was finally collected. The analysis was made using descriptive and inferential statistics.
Η Δημόσια Ιστορία ως συγκρουσιακό θέμα: Το Ολοκαύτωμα των Ελλήνων Εβραίων στο Διαδίκτυο
Creators: name: Ελευθερίου, Πολυξένη Κωνσταντίνου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Δημόσια Ιστορία
Συγκρουσιακά θέματα
Ολοκαύτωμα Ελλήνων Εβραίων
Public History
Controversial issues
Holocaust of the Greek Jews

description: Στην παρούσα μεταπτυχιακή εργασία θα παρουσιαστεί η αναπαράσταση του κατεξοχήν τραυματικού γεγονότος του Ολοκαυτώματος των Ελλήνων Εβραίων σε μία από τις ποικίλες εκδοχές της λεγόμενης «δημόσιας ιστορίας», το διαδίκτυο. Tα ευρήματα της έρευνας χωρίζονται στους εξής πέντε κύριους άξονες: ιστορική μνήμη και Ολοκαύτωμα των Ελλήνων Εβραίων (προσεγγίσεις, απώθηση τραυματικού παρελθόντος, εκδηλώσεις μνήμης, μνημεία και ιστορικοί τόποι για το Ολοκαύτωμα, λόγος των Ελλήνων Εβραίων επιζώντων), ιστορική συνείδηση και αναγνώριση ευθυνών για την εξόντωση των Ελλήνων Εβραίων (ανοχή, συνέργεια και δωσιλογισμός από τη μία μεριά, χριστιανική αλληλεγγύη και αντιφασιστική Αντίσταση από την άλλη μεριά), ποινικοποίηση της ιστορικής μνήμης (ευρωπαϊκοί νόμοι για την άρνηση του Ολοκαυτώματος, ελληνική νομοθεσία), ιστορικός αναθεωρητισμός και αρνητισμός του Ολοκαυτώματος (προοπτική του ιστορικού ρεβιζιονισμού, εκδοχές του νεοκομμουνισμού και του νεοαριστερού λόγου), αντισημιτισμός και αντισιωνισμός (επιβιώσεις και αναβιώσεις του αντισημιτισμού, προπαγανδιστικός αντισιωνιστικός λόγος, βανδαλισμοί και αντιεβραϊκά επεισόδια).
description: The present thesis is an effort to re-enact the traumatic event of the Greek Jews Holocaust in one of the various version of the so-called “public history”, namely the Internet (World Wide Web). The findings of this research can be categorized in the following five main themes: Historical memory and Holocaust of the Greek Jews (points of view, rejection of the traumatic past, memory events, monuments and historic places concerning the Holocaust, testimonies of Greek Jews survivors), Historical consciousness and recognition of responsibilities concerning the annihilation of the Greek Jews (tolerance, complicity and treason on the one hand, Christian solidarity and anti-fascist Resistance on the other), Penalization of the historical memory (European laws about the denial of the Holocaust, Greek legislation), Historical reconsideration and negativism toward the Holocaust (prospect of historical revisionism, version of neo-communism and neo-leftist argumentation), Anti-Semitism and anti-Zionism (survival and revival of anti-Semitism, anti-Zionist propaganda, vandalisms and anti-Jewish rioting).
Ultra-short pulse generation from mid-IR to THz range using plasma wakes and relativistic ionization fronts
Creators: name: Nie, Zan
name: Wu, Yipeng
name: Zhang, Chaojie
name: Mori, Warren B.
name: Joshi, Chan
name: Lu, Wei
name: Pai, Chih-Hao
name: Hua, Jianfei
name: Wang, Jyhpyng
Publisher: name: arXiv
Year: 2020
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: This paper discusses numerical and experimental results on frequency downshifting and upshifting of a 10 $μ$m infrared laser to cover the entire wavelength (frequency) range from $λ$=1-150 $μ$m ($ν$=300-2 THz) using two different plasma techniques. The first plasma technique utilizes frequency downshifting of the drive laser pulse in a nonlinear plasma wake. Based on this technique, we have proposed and demonstrated that in a tailored plasma structure multi-millijoule energy, single-cycle, long-wavelength IR (3-20 $μ$m) pulses can be generated by using an 810 nm Ti:sapphire drive laser. Here we extend this idea to the THz frequency regime. We show that sub-joule, terawatts, single-cycle terahertz (2-12 THz, or 150-25 $μ$m) pulses can be generated by replacing the drive laser with a picosecond 10 $μ$m CO$_2$ laser and a different shaped plasma structure. The second plasma technique employs frequency upshifting by colliding a CO$_2$ laser with a rather sharp relativistic ionization front created by ionization of a gas in less than half cycle (17 fs) of the CO$_2$ laser. Even though the electrons in the ionization front carry no energy, the frequency of the CO$_2$ laser can be upshifted due to the relativistic Doppler effect as the CO$_2$ laser pulse enters the front. The wavelength can be tuned from 1-10 $μ$m by simply changing the electron density of the front. While the upshifted light with $5
description: 7 figures
The Long Bar in the Milky Way. Corroboration of an old hypothesis
Creators: name: Lopez-Corredoira, M.
name: Cabrera-Lavers, A.
name: Mahoney, T. J.
name: Hammersley, P. L.
name: Garzon, F.
name: Gonzalez-Fernandez, C.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Recent GLIMPSE data have further confirmed the hypothesis of the existence of an in-plane long bar different from the bulge of the Milky Way with the same characteristics as emphasized some years ago by our team. In this paper, we present two new analyses that corroborate recent and earlier claims concerning the existence in our Galaxy of a long flat bar with approximate dimensions 7.8 kpc x 1.2 kpc x 0.2 kpc and a position angle of approximately 43 deg.: 1) star counts with 2MASS All-Sky Release and MSX data, which give an excess in the plane region along 0
description: 22 pages, 7 figures, accepted in AJ. We thank the GLIMPSE team for the re-discovery of the long bar we had found some years ago, although we would be more satisfied if they cited our papers too. V3: two new (not very important) sections added about the other parameters of the bar and the low contamination of the bulge; conclusions unchanged
The numerical renormalization group method for quantum impurity systems
Creators: name: Bulla, Ralf
name: Costi, Theo
name: Pruschke, Thomas
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: In the beginning of the 1970's, Wilson developed the concept of a fully non-perturbative renormalization group transformation. Applied to the Kondo problem, this numerical renormalization group method (NRG) gave for the first time the full crossover from the high-temperature phase of a free spin to the low-temperature phase of a completely screened spin. The NRG has been later generalized to a variety of quantum impurity problems. The purpose of this review is to give a brief introduction to the NRG method including some guidelines of how to calculate physical quantities, and to survey the development of the NRG method and its various applications over the last 30 years. These applications include variants of the original Kondo problem such as the non-Fermi liquid behavior in the two-channel Kondo model, dissipative quantum systems such as the spin-boson model, and lattice systems in the framework of the dynamical mean field theory.
description: 55 pages, 27 figures, submitted to Rev. Mod. Phys
Normal forms for hypersurfaces of finite type in $\mathbb C^2$
Creators: name: Kolar, Martin
Publisher: name: arXiv
Year: 2006
Subjects: subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 32V35; 32V40; 32T25

description: We construct normal forms for Levi degenerate hypersurfaces of finite type in $\mathbb C^2$. As one consequence, an explicit solution to the problem of local biholomorphic equivalence is obtained. Another consequence determines the dimension of the stability group of the hypersurface.
Dynamical Diffraction Theory for Wave Packet Propagation in Deformed Crystals
Creators: name: Sawada, Kei
name: Murakami, Shuichi
name: Nagaosa, Naoto
Publisher: name: arXiv
Year: 2006
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We develop a theory for the trajectory of an x ray in the presence of a crystal deformation. A set of equations of motion for an x-ray wave packet including the dynamical diffraction is derived, taking into account the Berry phase as a correction to geometrical optics. The trajectory of the wave packet has a shift of the center position due to a crystal deformation. Remarkably, in the vicinity of the Bragg condition, the shift is enhanced by a factor $ω/Δω$ ($ω$: frequency of an x ray, $Δω$: gap frequency induced by the Bragg reflection). Comparison with the conventional dynamical diffraction theory is also made.
description: 4 pages, 2 figures. Title changed
Black diring and infinite nonuniqueness
Creators: name: Iguchi, Hideo
name: Mishima, Takashi
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We show that the $S^1$-rotating black rings can be superposed by the solution generating technique. We analyze the black diring solution for the simplest case of multiple rings. There exists an equilibrium black diring where the conical singularities are cured by the suitable choice of physical parameters. Also there are infinite numbers of black dirings with the same mass and angular momentum. These dirings can have two different continuous limits of single black rings. Therefore we can transform the fat black ring to the thin ring with the same mass and angular momentum by way of the diring solutions.
description: 15 pages, 4 figures; Corrected the mass parameter and fig 4
Singular magnetic anisotropy in the nematic phase of FeSe
Creators: name: Zhou, R.
name: Scherer, D. D.
name: Mayaffre, H.
name: Toulemonde, P.
name: Ma, M.
name: Li, Y.
name: Andersen, B. M.
name: Julien, M. -H.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: FeSe is arguably the simplest, yet the most enigmatic, iron-based superconductor. Its nematic but non-magnetic ground state is unprecedented in this class of materials and stands out as a current puzzle. Here, our NMR measurements in the nematic state of mechanically detwinned FeSe reveal that both the Knight shift and the spin-lattice relaxation rate 1/T_1 possess an in-plane anisotropy opposite to that of the iron pnictides LaFeAsO and BaFe2As2. Using a microscopic electron model that includes spin-orbit coupling, our calculations show that an opposite quasiparticle weight ratio between the d_xz and d_yz orbitals leads to an opposite anisotropy of the orbital magnetic susceptibility, which explains our Knight shift results. We attribute this property to a different nature of nematic order in the two compounds, predominantly bond-type in FeSe and onsite ferro-orbital in pnictides. The T_1 anisotropy is found to be inconsistent with existing neutron scattering data in FeSe, showing that the spin fluctuation spectrum reveals surprises at low energy, possibly from fluctuations that do not break C_4 symmetry. Therefore, our results reveal that important information is hidden in these anisotropies and they place stringent constraints on the low-energy spin correlations as well as on the nature of nematicity in FeSe.
description: Submitted version. More recent version and Supplementary Information (24 pages) available upon request