cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Spinor-Vector Duality in fermionic Z2XZ2 heterotic orbifold models
Creators: name: Faraggi, Alon E.
name: Kounnas, Costas
name: Rizos, John
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We continue the classification of the fermionic Z2XZ2 heterotic string vacua with symmetric internal shifts. The space of models is spanned by working with a fixed set of boundary condition basis vectors and by varying the sets of independent Generalized GSO (GGSO) projection coefficients (discrete torsion). This includes the Calabi-Yau like compactifications with (2,2) world-sheet superconformal symmetry, as well as more general vacua with only (2,0) superconformal symmetry. In contrast to our earlier classification that utilized a montecarlo technique to generate random sets of GGSO phases, in this paper we present the results of a complete classification of the subclass of the models in which the four dimensional gauge group arises solely from the null sector. In line with the results of the statistical classification we find a bell shaped distribution that peaks at vanishing net number of generations and with ~15% of the models having three net chiral families. The complete classification reveals a novel spinor-vector duality symmetry over the entire space of vacua. The S V duality interchanges the spinor plus anti-spinor representations with vector representations. We present the data that demonstrates the spinor-vector duality. We illustrate the existence of a duality map in a concrete example. We provide a general algebraic proof for the existence of the S V duality map. We discuss the case of self-dual solutions with an equal number of vectors and spinors, in the presence and absence of E6 gauge symmetry, and present a couple of concrete examples of self-dual models without E6 symmetry.
description: standard LaTex; 29 pages; 6 figures
On the forbidden graphene's ZO (out-of-plane optic) phononic band-analog vibrational modes in fullerenes
Creators: name: Pedroza-Montero, Jesús N.
name: Garzón, Ignacio L.
name: Sauceda, Huziel E.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Other Condensed Matter (cond-mat.other)
subject: Atomic and Molecular Clusters (physics.atm-clus)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: The study of nanostructures' vibrational properties is at the core of nanoscience research, they are known to represent a fingerprint of the system as well as to hint the underlying nature of chemical bonds. In this work we focus on addressing how does the vibrational density of states (VDOS) of the carbon fullerene family ($C_n:~n=20\to720$ atoms) evolves from the molecular to the bulk material (graphene) behavior using density functional theory. We found that the fullerene's VDOS smoothly converges to the graphene characteristic shape-line with the only noticeable discrepancy in the frequency range of the out-of-plane optic (ZO) phonon band in graphene. From a comparison of both systems we obtain as main results that: 1)The pentagonal faces in the fullerenes impede the existence of the analog of the high frequency graphene's ZO phonons, 2)which in the context of phonons this could be interpreted as a compression (by 43\%) of the ZO phonon band by decreasing its maximum allowed radial-optic vibration frequency. 3)As a result, the deviation of fullerene's VDOS relative to graphene should result on important thermodynamical implications. The obtained insights can be extrapolated to other structures containing pentagonal rings such as nanostructure or as pentagonal defects in graphene.
description: 7 pages, 5 figures
title: Understanding the spatial dynamics of European sea bass: new insights on seasonal migration patterns from electronic tagging off the coast of west Brittany
Creators: name: de Pontual, Hélène
name: Ngo, Tran-Thanh
name: Lalire, Maxime
name: Lazure, Pascal
name: Garren, François
name: Drogou, Mickaël
name: Woillez, Mathieu
name: Fablet, Ronan
Publisher: name: ASC 2013 - Theme session O
Year: 2024
Subjects: Fisheries and aquaculture
Technologies and data

description: No abstracts are to be cited without prior reference to the author. European sea bass is a highly mobile species whose spatial dynamics remain poorly understood. In order to analyze adult migration patterns, we carried out tagging experiments (acoustic telemetry and data storage tags) off the coast of west Brittany. Acoustic tracking provided 3D behaviour used to parameterize a geolocation method from DST data (depth and temperature). To date, 21 DSTs out of 246 have been recovered. Our geolocation model (daily predicted probability maps issued from a HMM - hidden Markov model) combines both satellite SST data and the hydrodynamic model MARS3D. A sensitivity analysis demonstrates its robustness to recover consistent movement patterns. Fish with long times at liberty exhibited strong site fidelity to summer feeding ground. Reconstructed individual trajectories revealed different spawning migration patterns (mostly in the Bay of Biscay but also in the Celtic sea/English Channel). The joint analysis of horizontal and vertical movements showed seasonal behavioural shifts. Our results support the hypothesis of a fine scale spatial structuring at the population scale, a key issue poorly addressed by current management frameworks. It also provides key information for the understanding and the modelling of the spatial dynamics of the species under environmental forcing
Nanomechanical properties of few-layer graphene membranes
Creators: name: Poot, Menno
name: van der Zant, Herre S. J.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We have measured the mechanical properties of few-layer graphene and graphite flakes that are suspended over circular holes. The spatial profile of the flake's spring constant is measured with an atomic force microscope. The bending rigidity of and the tension in the membranes are extracted by fitting a continuum model to the data. For flakes down to eight graphene layers, both parameters show a strong thickness-dependence. We predict fundamental resonance frequencies of these nanodrums in the GHz range based on the measured bending rigidity and tension.
description: 9 pages, 3 figures, This article has been accepted by Appl. Phys. Lett. After it is published, it will be found at http://apl.aip.org/
Real Time Relativity: exploration learning of special relativity
Creators: name: Savage, C. M.
name: Searle, A.
name: McCalman, L.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Physics Education (physics.ed-ph)
subject: FOS: Physical sciences

description: Real Time Relativity is a computer program that lets students fly at relativistic speeds though a simulated world populated with planets, clocks, and buildings. The counterintuitive and spectacular optical effects of relativity are prominent, while systematic exploration of the simulation allows the user to discover relativistic effects such as length contraction and the relativity of simultaneity. We report on the physics and technology underpinning the simulation, and our experience using it for teaching special relativity to first year university students.
Quantization of the N=2 Supersymmetric KdV Hierarchy
Creators: name: Zeitlin, Anton M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: Quantum Algebra (math.QA)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We continue the study of the quantization of supersymmetric integrable KdV hierarchies. We consider the N=2 KdV model based on the $sl^{(1)}(2|1)$ affine algebra but with a new algebraic construction for the L-operator, different from the standard Drinfeld-Sokolov reduction. We construct the quantum monodromy matrix satisfying a special version of the reflection equation and show that in the classical limit, this object gives the monodromy matrix of N=2 supersymmetric KdV system. We also show that at both the classical and the quantum levels, the trace of the monodromy matrix (transfer matrix) is invariant under two supersymmetry transformations and the zero mode of the associated U(1) current.
description: LaTeX2e, 12 pages
Sparse optimal control of a phase field tumour model with mechanical effects
Creators: name: Garcke, Harald
name: Lam, Kei Fong
name: Signori, Andrea
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 49J20, 49K20, 35K57, 74B05, 35Q92

description: In this paper, we study an optimal control problem for a macroscopic mechanical tumour model based on the phase field approach. The model couples a Cahn--Hilliard type equation to a system of linear elasticity and a reaction-diffusion equation for a nutrient concentration. By taking advantage of previous analytical well-posedness results established by the authors, we seek optimal controls in the form of a boundary nutrient supply, as well as concentrations of cytotoxic and antiangiogenic drugs that minimise a cost functional involving mechanical stresses. Special attention is given to sparsity effects, where with the inclusion of convex non-differentiable regularisation terms to the cost functional, we can infer from the first-order optimality conditions that the optimal drug concentrations can vanish on certain time intervals.
description: 26 pages
Signatures of two-dimensionalisation of 3D turbulence in presence of rotation
Creators: name: Chakraborty, Sagar
Publisher: name: arXiv
Year: 2007
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: A reason has been given for the inverse energy cascade in the two-dimensionalised rapidly rotating 3D incompressible turbulence. For such system, literature shows a possibility of the exponent of wavenumber in the energy spectrum's relation to lie between -2 and -3. We argue the existence of a more strict range of -2 to -7/3 for the exponent in the case of rapidly rotating turbulence which is in accordance with the recent experiments. Also, a rigorous derivation for the two point third order structure function has been provided helping one to argue that even with slow rotation one gets, though dominated, a spectrum with the exponent -2.87, thereby hinting at the initiation of the two-dimensionalisation effect with rotation.
description: An extended and typos-corrected version of the earlier submission
title: Where do they come from? Spatial distributions and ontogenetic movements of goliath grouper (Epinephelus itajara) in the state of Florida
Creators: name: Tzadik, Orian E
name: Stallings, Christopher D
name: Jones, David L
name: Hollander, David J
Publisher: name: ASC 2013 - Theme session O
Year: 2024
Subjects: Fisheries and aquaculture
Technologies and data

description: No abstracts are to be cited without prior reference to the author. Goliath grouper (Family Epinephelidae) are considered to be critically endangered throughout their range, but, after a 22-year federal fishing moratorium, stocks have shown recent signs of recovery in Florida waters
title: Migratory and spawning behavior of lumpfish, Cyclopterus lumpus, as determined by temperature and depth recording data-storage tags
Creators: name: Kasper, Jacob M.
name: Jónsson, Sigurður Þór
name: Björnsson, Höskuldur
Publisher: name: ASC 2013 - Theme session O
Year: 2024
Subjects: Fisheries and aquaculture
Technologies and data

description: No abstracts are to be cited without prior reference to the author. In early 2013 the first data storage tagging program was conducted in the lumpfish, Cyclopterus lumpus, in Iceland. 85 female and seven male lumpfish, Cyclopterus lumpus, were tagged with datastorage tags recording pressure and temperature
Bifunctional Luneburg-fisheye Lens Based on the Manipulation of Spoof Surface Plasmons
Creators: name: Zhao, Jin
name: Wang, Yi-Dong
name: Yin, Li-Zheng
name: Han, Feng-Yuan
name: Huang, Tie-Jun
name: Liu, Pu-Kun
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Manipulation of spoof surface plasmons (SSPs) has recently intrigued enormous interest due to the capability of guiding waves with subwavelength footsteps. However, most of the previous studies, manifested for a single functionality, are not suitable for multifunctional integrated devices. Herein, a bifunctional Luneburg-fisheye lens is proposed based on a two-dimension metal pillar array. Firstly, by tuning the geometric dimension of the metal pillars in the array, its ability to precisely manipulate the excited SSPs along one direction is confirmed, achieving subwavelength focusing and imaging with the resolution up to 0.14 times the wavelength. Then, separately controlling the propagation of the SSPs along the orthotropic directions is further implemented, and the bifunctional Luneburg-fisheye lens is realized. The bifunctional lens is characterized as a Luneburg one along the x-axis, whereas in the y-axis, it presents the properties of a Maxwell fisheye lens. The experimental results almost immaculately match with the simulation ones. This bifunctional lens can validly reduce the system complexity and exert flexibility in multifunctional applications, while the proposed metal pillar-based design method broadens the application range of gradient refractive-index lens in the microwaves, terahertz, and even optical ranges.
description: 9 pages, 5 figures,
Raman scattering study of the a-GeTe structure and possible mechanism for the amorphous-to-crystal transition
Creators: name: Andrikopoulos, K. S.
name: Yannopoulos, S. N.
name: Voyiatzis, G. A.
name: Kolobov, A. V.
name: Ribes, M.
name: Tominaga, J.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We report on an inelastic (Raman) light scattering study of the local structure of amorphous GeTe films. A detailed analysis of the temperature-reduced Raman spectra has shown that appreciable structural changes occur as a function of temperature. These changes involve modifications of atomic arrangements such as to facilitate the rapid amorphous-to-crystal transformation, which is the major advantage of phase-change materials used in optical data storage media. A particular structural model, supported by polarization analysis, is proposed being compatible with the experimental data as regards both the structure of a-GeTe and the crystallization transition. The remarkable difference between the Raman spectrum of the crystal and the glass can thus naturally be accounted for.
description: Published in: J. Phys. Condens. Matter. 18, 965-979 (2006)
Maximum entropy principle and texture formation
Creators: name: Arminjon, Mayeul
name: Imbault, Didier
Publisher: name: arXiv
Year: 2006
Subjects: subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: The macro-to-micro transition in a heterogeneous material is envisaged as the selection of a probability distribution by the Principle of Maximum Entropy (MAXENT). The material is made of constituents, e.g. given crystal orientations. Each constituent is itself made of a large number of elementary constituents. The relevant probability is the volume fraction of the elementary constituents that belong to a given constituent and undergo a given stimulus. Assuming only obvious constraints in MAXENT means describing a maximally disordered material. This is proved to have the same average stimulus in each constituent. By adding a constraint in MAXENT, a new model, potentially interesting e.g. for texture prediction, is obtained.
Gate controlled unitary operation on flying spin qubits in quantum Hall edge states
Creators: name: Shimizu, Takase
name: Nakamura, Taketomo
name: Hashimoto, Yoshiaki
name: Endo, Akira
name: Katsumoto, Shingo
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Spin and orbital freedoms of electrons traveling on spin-resolved quantum Hall edge states (quantum Hall ferromagnets) are maximally entangled. The unitary operations on these two freedoms are hence equivalent, which means one can manipulate the spins with non-magnetic methods through the orbitals. If one takes the quantization axis of spins along the magnetization axis, the zenith angle is determined by the partition rate of spin-separated edges while the azimuth angle is defined as the phase difference between the edges. Utilizing these properties, we have realized electrically controlled unitary operation on the electron spins on the quantum Hall ferromagnets. The zenith angle of the spin was controlled through the radius of gyration at a corner by means of applying voltage to a thin gate placed at one edge. The subsequent rotation in the azimuth angle was controlled via the distance between the edge channels also by a gate voltage. The combination of the two operations constitutes the first systematic electric operation on spins in the quantum Hall edge channels.
Transfer Learning and Augmentation for Word Sense Disambiguation
Creators: name: Kohli, Harsh
Publisher: name: arXiv
Year: 2021
Subjects: subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences

description: Many downstream NLP tasks have shown significant improvement through continual pre-training, transfer learning and multi-task learning. State-of-the-art approaches in Word Sense Disambiguation today benefit from some of these approaches in conjunction with information sources such as semantic relationships and gloss definitions contained within WordNet. Our work builds upon these systems and uses data augmentation along with extensive pre-training on various different NLP tasks and datasets. Our transfer learning and augmentation pipeline achieves state-of-the-art single model performance in WSD and is at par with the best ensemble results.
description: 10 pages, 3 figures. Accepted at the 43rd European Conference on Information Retrieval (ECIR) 2021
Electric Control of Spin Helicity in a Magnetic Ferroelectric
Creators: name: Yamasaki, Y.
name: Sagayama, H.
name: Goto, T.
name: Matsuura, M.
name: Hirota, K.
name: Arima, T.
name: Tokura, Y.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Magnetic ferroelectrics or multiferroics, which are currently extensively explored, may provide a good arena to realize a novel magnetoelectric function. Here we demonstrate the genuine electric control of the spiral magnetic structure in one of such magnetic ferroelectrics, TbMnO3. A spin-polarized neutron scattering experiment clearly shows that the spin helicity, clockwise or counter-clockwise, is controlled by the direction of spontaneous polarization and hence by the polarity of the small cooling electric field.
description: 4 pages, 3 figures
(2+1) Lorentzian quantum cosmology from spin-foams: opportunities and obstacles for semi-classicality
Creators: name: Jercher, Alexander F.
name: Simão, José Diogo
name: Steinhaus, Sebastian
Publisher: name: arXiv
Year: 2024
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We construct an effective cosmological spin-foam model for a (2+1) dimensional spatially flat universe, discretized on a hypercubical lattice, containing both space- and time-like regions. Our starting point is the recently proposed coherent state spin-foam model for (2+1) Lorentzian quantum gravity. The full amplitude is assumed to factorize into single vertex amplitudes with boundary data corresponding to Lorentzian 3-frusta. A stationary phase approximation is performed at each vertex individually, where the inverse square root of the Hessian determinant serves as a measure for the effective path integral. Additionally, a massive scalar field is coupled to the geometry, and we show that its mass renders the partition function convergent. For a single 3-frustum with time-like struts, we compute the expectation value of the bulk strut length and show that it generically agrees with the classical solutions and that it is a discontinuous function of the scalar field mass. Allowing the struts to be space-like introduces causality violations, which drive the expectation values away from the classical solutions due to the lack of an exponential suppression of these configurations. This is a direct consequence of the semi-classical amplitude only containing the real part of deficit angles, in contrast with the Lorentzian Regge action used in effective spin-foams. We give an outlook on how to evaluate the partition function on an extended discretization including a bulk spatial slice. This serves as a foundation for future investigations of physically interesting scenarios such as a quantum bounce or the viability of massive scalar field clocks. Our results demonstrate that the effective path integral in the causally regular sector serves as a viable quantum cosmology model, but that the agreement of expectation values with classical solutions is tightly bound to the path integral measure.
description: 51 + 11 pages, 17 figures
title: Insights into mixing and movement of albacore Thunnus alalunga derived from trace elements in otoliths
Creators: name: Macdonald, Jed I.
name: Farley, Jessica H.
name: Clear, Naomi P.
name: Williams, Ashley J.
name: Carter, Thor I.
name: Davies, Campbell R.
name: Nicol, Simon J.
Publisher: name: ASC 2013 - Theme session O
Year: 2024
Subjects: Fisheries and aquaculture
Technologies and data

description: No abstracts are to be cited without prior reference to the author. Information on the movements and stock structure of commercially important tunas underpins the effective management of exploited populations. For South Pacific albacore (Thunnus alalunga), longstanding questions remain regarding the degree of connectivity among larval pools, the migration routes of juveniles and adults and the biophysical factors influencing these processes. Using laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS), we measured trace elements (Li, Mg, Mn, Cu, Sr, Ba, Pb, Ca) in albacore otoliths collected across a broad geographical range to address these knowledge gaps. Capture locations in French Polynesia, New Caledonia and New Zealand were discriminated with high accuracy (overall 85% of individuals correctly classified), with some evidence of larval mixing for fish sampled from New Caledonia and New Zealand, but not French Polynesia. Seasonal cycles in Sr:Ca and Ba:Ca were observed along transects encompassing the full life history of individuals. These patterns may reflect migrations across ocean fronts; however, the vertical behaviours of albacore and the lack of opportunities for controlled experiments on elemental uptake complicate environmental reconstructions. Expanding the present analysis and integrating multiple data sources (e.g. commercial catches, tag returns, otolith δ13C and δ18O, ocean circulation models) could help clarify how environmental forces shape albacore behaviour and distribution
title: Seasonal offshore‐onshore migration of anglerfish Lophius piscatorius in Faroese waters
Creators: name: Ofstad, Lise H.
name: Steingrund, Petur
name: Pedersen, Torstein
Publisher: name: ASC 2013 - Theme session O
Year: 2024
Subjects: Fisheries and aquaculture
Technologies and data

description: No abstracts are to be cited without prior reference to the author. Migration pattern of anglerfish in Faroese waters is poorly known. Seasonal migration and vertical movement of anglerfish was investigated by mark‐recapture methods, including data storage tags, and compared to information from traditional tags, scientific trawl surveys and the commercial fishery. A distinctive seasonal offshore‐onshore migration pattern was observed as anglerfish occupied shallow waters (300 m) in winter. This seasonal movement was most pronounced for large (>70 cm) sexually mature fish, hence, indicating that spawning occurs in deep waters during winter and feeding in shallow waters during summer. Approximately 5% of the total data storage tag recordings showed more than 5 m vertical movement between two following hourly recordings. There was a seasonal and diurnal difference in vertical migration activity as anglerfish was more vertically active in winter than summer and during night time than day time. This indicates light intensity and day length influence vertical migration of anglerfish. Anglerfish was mostly located in relatively warm waters (6.5–11ºC) and seldom located in temperatures colder than 4ºC.
Optimal and Efficient Decoding of Concatenated Quantum Block Codes
Creators: name: Poulin, David
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We consider the problem of optimally decoding a quantum error correction code -- that is to find the optimal recovery procedure given the outcomes of partial "check" measurements on the system. In general, this problem is NP-hard. However, we demonstrate that for concatenated block codes, the optimal decoding can be efficiently computed using a message passing algorithm. We compare the performance of the message passing algorithm to that of the widespread blockwise hard decoding technique. Our Monte Carlo results using the 5 qubit and Steane's code on a depolarizing channel demonstrate significant advantages of the message passing algorithms in two respects. 1) Optimal decoding increases by as much as 94% the error threshold below which the error correction procedure can be used to reliably send information over a noisy channel. 2) For noise levels below these thresholds, the probability of error after optimal decoding is suppressed at a significantly higher rate, leading to a substantial reduction of the error correction overhead.
description: Published version
Current Exchanges and Unconstrained Higher Spins
Creators: name: Francia, D.
name: Mourad, J.
name: Sagnotti, A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The (Fang-)Fronsdal formulation for free fully symmetric (spinor-) tensors rests on (gamma-)trace constraints on gauge fields and parameters. When these are relaxed, glimpses of the underlying geometry emerge: the field equations extend to non-local expressions involving the higher-spin curvatures, and with only a pair of additional fields an equivalent ``minimal'' local formulation is also possible. In this paper we complete the discussion of the ``minimal'' formulation for fully symmetric (spinor-) tensors, constructing one-parameter families of Lagrangians and extending them to (A)dS backgrounds. We then turn on external currents, that in this setting are subject to conventional conservation laws and, by a close scrutiny of current exchanges in the various formulations, we clarify the precise link between the local and non-local versions of the theory. To this end, we first show the equivalence of the constrained and unconstrained local formulations, and then identify a unique set of non-local Lagrangian equations which behave in exactly the same fashion in current exchanges.
description: 37 pages, Latex. Typos corrected, note and references added. Final version to appear in Nucl. Phys. B
Shock width measured under liquid and solid conditions in a 2D dusty plasma
Creators: name: Kananovich, Anton
name: Goree, J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Widths of shocks are compared, under liquid and solid conditions, for a two-dimensional layer of charged microspheres levitated in a plasma. In this strongly coupled dusty plasma, a shock was launched as a blast wave by moving an exciter wire at a supersonic speed and then bringing it to a halt. Runs were repeated with the layer of microspheres prepared two ways: a crystalline-like solid, and a liquid. The liquid was sustained using laser heating, with conditions that were otherwise the same as in the solid. The shock width was found to be less in a liquid than in a solid, where it was 4 to 6 lattice constants. These measurements were based on the high-gradient region of density profiles. The profiles were obtained from particle coordinates, measured by high-speed video imaging. The spatial resolution was improved by combining particle coordinates, in the shock's frame of reference, from a sequence of images.
Comparison of fragment partitions production in peripheral and central collisions
Creators: name: Bonnet, E.
name: Borderie, B.
name: Neindre, N. Le
name: Rivet, M. F.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: Ensembles of single-source events, produced in peripheral and central collisions and correponding respectively to quasi-projectile and quasi-fusion sources, are analyzed. After selections on fragment kinematic properties, excitation energies of the sources are derived using the calorimetric method and the mean behaviour of fragments of the two ensembles are compared. Differences observed in their partitions, especially the charge asymmetry, can be related to collective energy deposited in the systems during the collisions.
description: 7 pages, 2 figures, presented at the International Workshop on Multifragmentation and Related Topics, Caen France, 4-7th november 2007 (IWM2007)
Accurate phonon blockade detector composed of a quadratically coupled optomechanical system
Creators: name: Zeng, Ye-Xiong
name: Gebremariam, Tesfay
name: Shen, Jian
name: Xiong, Biao
name: Li, Chong
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The observation of phonon blockade in a nanomechanical oscillator is clear evidence of its quantum nature. However, it is still a severe challenge to measure the strong phonon blockade in an optomechanical system with effective nonlinear coupling. In this paper, we propose a theoretical proposal for detecting the phonon blockade effect in a quadratically coupled optomechanical system by exploiting supervised machine learning. The detected optical signals are injected into the neural network as the input, while the output is the mechanical equal-time second-order correlation. Our results show our scheme performs superior performance on detecting phonon blockade. Specifically, it is efficient for nonlinear coupling systems; it performs a high precision for strong photon blockade; it is robust against the small disturbance of system parameters. Our work opens a promising way to build a phonon blockade detector.
description: 7 figures
Concurrent CPU-GPU Task Programming using Modern C++
Creators: name: Huang, Tsung-Wei
name: Lin, Yibo
Publisher: name: arXiv
Year: 2022
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: In this paper, we introduce Heteroflow, a new C++ library to help developers quickly write parallel CPU-GPU programs using task dependency graphs. Heteroflow leverages the power of modern C++ and task-based approaches to enable efficient implementations of heterogeneous decomposition strategies. Our new CPU-GPU programming model allows users to express a problem in a way that adapts to effective separation of concerns and expertise encapsulation. Compared with existing libraries, Heteroflow is more cost-efficient in performance scaling, programming productivity, and solution generality. We have evaluated Heteroflow on two real applications in VLSI design automation and demonstrated the performance scalability across different CPU-GPU numbers and problem sizes. At a particular example of VLSI timing analysis with million-scale tasking, Heteroflow achieved 7.7x runtime speed-up (99 vs 13 minutes) over a baseline on a machine of 40 CPU cores and 4 GPUs.
Nonnegative Matrix Factorization with Toeplitz Penalty
Creators: name: Corsetti, Matthew
name: Fokoué, Ernest
Publisher: name: arXiv
Year: 2020
Subjects: subject: Machine Learning (stat.ML)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences
subject: 62H35

description: Nonnegative Matrix Factorization (NMF) is an unsupervised learning algorithm that produces a linear, parts-based approximation of a data matrix. NMF constructs a nonnegative low rank basis matrix and a nonnegative low rank matrix of weights which, when multiplied together, approximate the data matrix of interest using some cost function. The NMF algorithm can be modified to include auxiliary constraints which impose task-specific penalties or restrictions on the cost function of the matrix factorization. In this paper we propose a new NMF algorithm that makes use of non-data dependent auxiliary constraints which incorporate a Toeplitz matrix into the multiplicative updating of the basis and weight matrices. We compare the facial recognition performance of our new Toeplitz Nonnegative Matrix Factorization (TNMF) algorithm to the performance of the Zellner Nonnegative Matrix Factorization (ZNMF) algorithm which makes use of data-dependent auxiliary constraints. We also compare the facial recognition performance of the two aforementioned algorithms with the performance of several preexisting constrained NMF algorithms that have non-data-dependent penalties. The facial recognition performances are evaluated using the Cambridge ORL Database of Faces and the Yale Database of Faces.
description: 15 pages, 6 figures, 3 tables
title: Piscivore meets pisces: interactions between grey seals and fish on the Eastern Scotian Shelf and southern Gulf of St. Lawrence
Creators: name: Lidgard, Damian C.
name: Bowen, W. Don
name: Jonsen, Ian D.
name: Iverson, Sara J.
Publisher: name: ASC 2013 - Theme session O
Year: 2024
Subjects: Fisheries and aquaculture
Technologies and data

description: No abstracts are to be cited without prior reference to the author. Top-down effects of upper-trophic level predators play important roles in ecosystem structure and functioning. Nevertheless, interactions between pinnipeds and their prey remain poorly understood. This uncertainty has fueled debate on the impact of seal predation on fish stocks. We show that novel combination of acoustic (Vemco Mobile Transceiver, VMT) and GPS technology can be used to determine the spatio-temporal pattern of interactions between grey seals (Halichoerus grypus) and fish species in two marine ecosystems, the Eastern Scotian Shelf and southern Gulf of St. Lawrence, Canada. During four years of study, 16 of 64 adult grey seals recorded 1,117 detections from various fish species including 17 adult Atlantic cod (Gadus morhua), 7 Atlantic salmon (Salmo salar) and one American eel (Anguilla rostrata) implanted with coded acoustics tags. An examination of the spatiotemporal pattern of these interactions suggested that none involved predation. These preliminary results provide proof-of-concept that predators fitted with VMT and GPS tags can provide information on species locations in areas where fixed receiver arrays are not present and allow new insights into the nature of predator-prey interactions in otherwise inaccessible environments.
Proposal Writing GEOGLAM Webinar
Creators: name: GEOGLAM
Publisher: name: GEO Knowledge Hub
Year: 2024

description: This knowledge package is dedicated to the Proposal Writing Webinar organized by GEOGLAM. 
It offers a comprehensive collection of resources from the webinar, including presentation materials and video recording. You can find the resources under the "Other" category.
These resources provide valuable guidance to enhance your proposal writing skills and apply best practices in project development.
title: The Ocean Tracking Network (OTN) Canada: a template for developing other integrated research networks within the global OTN
Creators: name: Iverson, Sara J.
Publisher: name: ASC 2013 - Theme session O
Year: 2024
Subjects: Fisheries and aquaculture
Technologies and data

description: No abstracts are to be cited without prior reference to the author. The Ocean Tracking Network (OTN) is the world’s aquatic animal tracking network: a global research and technology development platform and partnership that aims to revolutionize the ways that oceans and freshwater ecosystems are monitored and understood. Headquartered at Dalhousie University, Halifax, NS, OTN uses sonic and other telemetry technologies (satellite tags, archival data-storage tags) to document movements and survival of marine animals. OTN is creating a global network of acoustic receivers and oceanographic sensors (deployed in all the world’s oceans and connecting waters, spanning seven continents), which record animal detections, movements, and interactions, in addition to oceanographic observations; is establishing a global network of users with a common database; and is demonstrating technologies that link animal locations and movements to oceanographic/environmental conditions. OTN Canada is the 7-year Canada-wide integrative research network program designed to use and develop OTN technologies and infrastructure to better understand changing marine ecosystems across Canada, to demonstrate how we can learn about these ecosystems through cutting-edge collaborative research, and to contribute to global observation of coastal and offshore ecosystems. Through this integrative approach of a national network of researchers, with international links and outreach, OTN Canada serves as a prototype research hub for other regions worldwide
title: Let’s do it again: Closing the book on a pilot in situ redfish tagging experiment with Underwater Tagging Equipment
Creators: name: Kristinsson, Kristján
name: Jónsson, Sigurður Þór
name: Björnsson, Höskuldur
name: Guðbjörnsson, Sigmar
name: Sigurðsson, Þorsteinn
Publisher: name: ASC 2013 - Theme session O
Year: 2024
Subjects: Fisheries and aquaculture
Technologies and data

description: No abstracts are to be cited without prior reference to the author. In 2003-2008 2,777 beaked redfish (Sebastes mentella) were tagged in situ with remotely operated Underwater Tagging Equipment (UTE) developed in collaboration between Marine Research Institute in Iceland and marine-device manufacturer Star-Oddi. Tagging redfish in their own environment avoiding the hazardous trip to the surface is made possible by attaching the UTE in front of the codend of a pelagic or demersal trawl and tagging with a remotely operated robot. The main objective of the research has been studying both vertical and horizontal migration patterns of beaked redfish stocks in the Irminger Sea and adjacent waters. Of the tagged fish, 62 (2.3%) have been recaptured. The experiment included tagging 105 redfish with electronic data-storage tags (DST) of type 'micro', recording pressure and temperature but, none have been recaptured to date. The distribution of days at liberty is wide with the longest time at liberty almost 7 years and the longest distance travelled over 300 nautical miles, with few individuals migrating between defined stock units. Despite the UTE being the only known successful tool for tagging redfish at great depths only Iceland has used it. We, therefore, believe the experiment ‘deserves to be repeated’ with further development of UTE.
On optimization of the metal ion production by Electron Cyclotron Resonance Ion Sources
Creators: name: Mironov, V.
name: Bogomolov, S.
name: Bondarchenko, A.
name: Efremov, A.
name: Kuzmenkov, K.
name: Loginov, V.
name: Pugachev, D.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Accelerator Physics (physics.acc-ph)
subject: FOS: Physical sciences

description: The three-dimensional NAM-ECRIS model is applied for studying the metal ion production in the DECRIS-PM Electron Cyclotron Resonance Ion Source. Experimentally measured extracted ion currents are accurately reproduced with the model. Parameters of the injection of metal vapors into the source are optimized. It is found that the axial injection of the highly directional fluxes allows increasing the extracted ion currents of the highly charged calcium ions by factor of 1.5. The reason for the gain in the currents is formation of internal barrier for the ions inside the plasma, which increase the ion extraction and production efficiency. Benefits of injecting the singly-charged calcium ions instead of atoms are discussed.
Can we trust the standardized mortality ratio? A formal analysis and evaluation based on axiomatic requirements
Creators: name: Roessler, Martin
name: Schmitt, Jochen
name: Schoffer, Olaf
Publisher: name: arXiv
Year: 2020
Subjects: subject: Applications (stat.AP)
subject: Other Statistics (stat.OT)
subject: FOS: Computer and information sciences

description: Background: The standardized mortality ratio (SMR) is often used to assess and compare hospital performance. While it has been recognized that hospitals may differ in their SMRs due to differences in patient composition, there is a lack of rigorous analysis of this and other - largely unrecognized - properties of the SMR. Methods: This paper proposes five axiomatic requirements for adequate standardized mortality measures: strict monotonicity, case-mix insensitivity, scale insensitivity, equivalence principle, and dominance principle. Given these axiomatic requirements, effects of variations in patient composition, hospital size, and actual and expected mortality rates on the SMR were examined using basic algebra and calculus. In this regard, we distinguished between standardization using expected mortality rates derived from a different dataset (external standardization) and standardization based on a dataset including the considered hospitals (internal standardization). Results: Under external standardization, the SMR fulfills the axiomatic requirements of strict monotonicity and scale insensitivity but violates the requirement of case-mix insensitivity, the equivalence principle, and the dominance principle. All axiomatic requirements not fulfilled under external standardization are also not fulfilled under internal standardization. In addition, the SMR under internal standardization is scale sensitive and violates the axiomatic requirement of strict monotonicity. Conclusions: The SMR fulfills only two (none) out of the five proposed axiomatic requirements under external (internal) standardization. Generally, the SMRs of hospitals are differently affected by variations in case mix and actual and expected mortality rates unless the hospitals are identical in these characteristics. These properties hamper valid assessment and comparison of hospital performance based on the SMR.
Be It Unresolved: Measuring Time Delays from Lensed Supernovae
Creators: name: Bag, Satadru
name: Kim, Alex G.
name: Linder, Eric V.
name: Shafieloo, Arman
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Gravitationally lensed Type Ia supernovae may be the next frontier in cosmic probes, able to deliver independent constraints on dark energy, spatial curvature, and the Hubble constant. Measurements of time delays between the multiple images become more incisive due to the standardized candle nature of the source, monitoring for months rather than years, and partial immunity to microlensing. While currently extremely rare, hundreds of such systems should be detected by upcoming time domain surveys. Even more will have the images spatially unresolved, with the observed lightcurve a superposition of time delayed image fluxes. We investigate whether unresolved images can be recognized as lensed sources given only lightcurve information, and whether time delays can be extracted robustly. We develop a method that successfully identifies such systems, with a false positive rate of $\lesssim 5\%$, and measures the time delays with a completeness of $\gtrsim 93\%$ and with a bias of $\lesssim 0.5\%$ for $Δt_{\rm fit} \gtrsim 10$ days.
description: 18 pages, 15 figures
Boosting small-scale structure via primordial black holes and implications for sub-GeV dark matter annihilation
Creators: name: Kadota, Kenji
name: Silk, Joseph
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We explore the possibility that the annihilation of dark matter (DM) is boosted due to enhanced substructure in the presence of primordial black holes (PBHs) which constitute a sub-component of DM. The PBHs can generate entropy fluctuations at the small scales which trigger early structure formation, and a large fraction of the whole DM can reside in these collapsed objects that formed at high redshift ($z\gtrsim 100$). Such early forming minihalos consequently possess higher densities than those in the conventional scenarios (without PBHs) and would be more resilient to tidal disruptions. Our scenarios of the annihilation boost due to DM substructures are of particular interest for light ($< 1$ GeV) DM which has been less explored compared to heavier DM in the presence of the PBHs.
description: 11 pages, 6 figures
title: Detection Efficiency of Vemco Mobile Transceivers Deployed on Grey Seals (Halichoerus grypus) on the Scotian Shelf
Creators: name: Baker, Laurie L.
name: Jonsen, Ian D.
name: Lidgard, Damian C.
name: Flemming, Joanna Mills
name: Bowen, Don
name: Iverson, Sara J.
Publisher: name: ASC 2013 - Theme session O
Year: 2024
Subjects: Fisheries and aquaculture
Technologies and data

description: No abstracts are to be cited without prior reference to the author. Understanding the nature of inter-specific and conspecific interactions in the ocean is challenging because direct observation is usually impossible. The development of two-way coded Vemco Mobile Transceivers (VMT) and satellite-linked GPS tags provides a unique opportunity to elucidate between and within species interactions in space and time. In order to interpret interactions we must accurately define their locations, duration, and frequency, which requires accurate knowledge of tag performance. We evaluated VMT detection efficiency deployed on grey seals (Sable Island, NS, Canada) in response to environmental characteristics and seal behaviour. We used generalized additive modelling techniques (GAM) to compare expected detections calculated from the GPS data to those observed, and corroborated these findings using the raw ping data. Distance between seals, wind stress, and minimum depth were the most important predictors of detection success. However, other environmental characteristics postulated to affect sound propagation, including temperature and depth properties, were not important in the model.
Analytical solutions for two-level systems with damping
Creators: name: Brouder, Christian
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A method is proposed to transform any analytic solution of the Bloch equation into an analytic solution of the Landau-Lifshitz-Gilbert equation. This allows for the analytical description of the dynamics of a two level system with damping. This method shows that damping turns the linear Schrödinger equation of a two-level system into a nonlinear Schrödinger equation. As applications, it is shown that damping has a relatively mild influence on self-induced transparency but destroys dynamical localization.
description: 4 pages